Adding upstream version 1.20.14.upstream/1.20.14upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

25 files changed, 15570 insertions, 0 deletions

diff --git a/src/cmd/compile/internal/noder/codes.go b/src/cmd/compile/internal/noder/codes.go
new file mode 100644
index 0000000..c1ee8d1
--- /dev/null
+++ b/src/cmd/compile/internal/noder/codes.go
@@ -0,0 +1,87 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import "internal/pkgbits"
+
+// A codeStmt distinguishes among statement encodings.
+type codeStmt int
+
+func (c codeStmt) Marker() pkgbits.SyncMarker { return pkgbits.SyncStmt1 }
+func (c codeStmt) Value() int                 { return int(c) }
+
+const (
+	stmtEnd codeStmt = iota
+	stmtLabel
+	stmtBlock
+	stmtExpr
+	stmtSend
+	stmtAssign
+	stmtAssignOp
+	stmtIncDec
+	stmtBranch
+	stmtCall
+	stmtReturn
+	stmtIf
+	stmtFor
+	stmtSwitch
+	stmtSelect
+)
+
+// A codeExpr distinguishes among expression encodings.
+type codeExpr int
+
+func (c codeExpr) Marker() pkgbits.SyncMarker { return pkgbits.SyncExpr }
+func (c codeExpr) Value() int                 { return int(c) }
+
+// TODO(mdempsky): Split expr into addr, for lvalues.
+const (
+	exprConst  codeExpr = iota
+	exprLocal           // local variable
+	exprGlobal          // global variable or function
+	exprCompLit
+	exprFuncLit
+	exprFieldVal
+	exprMethodVal
+	exprMethodExpr
+	exprIndex
+	exprSlice
+	exprAssert
+	exprUnaryOp
+	exprBinaryOp
+	exprCall
+	exprConvert
+	exprNew
+	exprMake
+	exprNil
+	exprFuncInst
+	exprRecv
+	exprReshape
+)
+
+type codeAssign int
+
+func (c codeAssign) Marker() pkgbits.SyncMarker { return pkgbits.SyncAssign }
+func (c codeAssign) Value() int                 { return int(c) }
+
+const (
+	assignBlank codeAssign = iota
+	assignDef
+	assignExpr
+)
+
+// A codeDecl distinguishes among declaration encodings.
+type codeDecl int
+
+func (c codeDecl) Marker() pkgbits.SyncMarker { return pkgbits.SyncDecl }
+func (c codeDecl) Value() int                 { return int(c) }
+
+const (
+	declEnd codeDecl = iota
+	declFunc
+	declMethod
+	declVar
+	declOther
+)
diff --git a/src/cmd/compile/internal/noder/decl.go b/src/cmd/compile/internal/noder/decl.go
new file mode 100644
index 0000000..07353cc
--- /dev/null
+++ b/src/cmd/compile/internal/noder/decl.go
@@ -0,0 +1,352 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"go/constant"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+)
+
+// TODO(mdempsky): Skip blank declarations? Probably only safe
+// for declarations without pragmas.
+
+func (g *irgen) decls(res *ir.Nodes, decls []syntax.Decl) {
+	for _, decl := range decls {
+		switch decl := decl.(type) {
+		case *syntax.ConstDecl:
+			g.constDecl(res, decl)
+		case *syntax.FuncDecl:
+			g.funcDecl(res, decl)
+		case *syntax.TypeDecl:
+			if ir.CurFunc == nil {
+				continue // already handled in irgen.generate
+			}
+			g.typeDecl(res, decl)
+		case *syntax.VarDecl:
+			g.varDecl(res, decl)
+		default:
+			g.unhandled("declaration", decl)
+		}
+	}
+}
+
+func (g *irgen) importDecl(p *noder, decl *syntax.ImportDecl) {
+	g.pragmaFlags(decl.Pragma, 0)
+
+	// Get the imported package's path, as resolved already by types2
+	// and gcimporter. This is the same path as would be computed by
+	// parseImportPath.
+	switch pkgNameOf(g.info, decl).Imported().Path() {
+	case "unsafe":
+		p.importedUnsafe = true
+	case "embed":
+		p.importedEmbed = true
+	}
+}
+
+// pkgNameOf returns the PkgName associated with the given ImportDecl.
+func pkgNameOf(info *types2.Info, decl *syntax.ImportDecl) *types2.PkgName {
+	if name := decl.LocalPkgName; name != nil {
+		return info.Defs[name].(*types2.PkgName)
+	}
+	return info.Implicits[decl].(*types2.PkgName)
+}
+
+func (g *irgen) constDecl(out *ir.Nodes, decl *syntax.ConstDecl) {
+	g.pragmaFlags(decl.Pragma, 0)
+
+	for _, name := range decl.NameList {
+		name, obj := g.def(name)
+
+		// For untyped numeric constants, make sure the value
+		// representation matches what the rest of the
+		// compiler (really just iexport) expects.
+		// TODO(mdempsky): Revisit after #43891 is resolved.
+		val := obj.(*types2.Const).Val()
+		switch name.Type() {
+		case types.UntypedInt, types.UntypedRune:
+			val = constant.ToInt(val)
+		case types.UntypedFloat:
+			val = constant.ToFloat(val)
+		case types.UntypedComplex:
+			val = constant.ToComplex(val)
+		}
+		name.SetVal(val)
+
+		out.Append(ir.NewDecl(g.pos(decl), ir.ODCLCONST, name))
+	}
+}
+
+func (g *irgen) funcDecl(out *ir.Nodes, decl *syntax.FuncDecl) {
+	assert(g.curDecl == "")
+	// Set g.curDecl to the function name, as context for the type params declared
+	// during types2-to-types1 translation if this is a generic function.
+	g.curDecl = decl.Name.Value
+	obj2 := g.info.Defs[decl.Name]
+	recv := types2.AsSignature(obj2.Type()).Recv()
+	if recv != nil {
+		t2 := deref2(recv.Type())
+		// This is a method, so set g.curDecl to recvTypeName.methName instead.
+		g.curDecl = t2.(*types2.Named).Obj().Name() + "." + g.curDecl
+	}
+
+	fn := ir.NewFunc(g.pos(decl))
+	fn.Nname, _ = g.def(decl.Name)
+	fn.Nname.Func = fn
+	fn.Nname.Defn = fn
+
+	fn.Pragma = g.pragmaFlags(decl.Pragma, funcPragmas)
+	if fn.Pragma&ir.Systemstack != 0 && fn.Pragma&ir.Nosplit != 0 {
+		base.ErrorfAt(fn.Pos(), "go:nosplit and go:systemstack cannot be combined")
+	}
+	if fn.Pragma&ir.Nointerface != 0 {
+		// Propagate //go:nointerface from Func.Pragma to Field.Nointerface.
+		// This is a bit roundabout, but this is the earliest point where we've
+		// processed the function's pragma flags, and we've also already created
+		// the Fields to represent the receiver's method set.
+		if recv := fn.Type().Recv(); recv != nil {
+			typ := types.ReceiverBaseType(recv.Type)
+			if orig := typ.OrigType(); orig != nil {
+				// For a generic method, we mark the methods on the
+				// base generic type, since those are the methods
+				// that will be stenciled.
+				typ = orig
+			}
+			meth := typecheck.Lookdot1(fn, typecheck.Lookup(decl.Name.Value), typ, typ.Methods(), 0)
+			meth.SetNointerface(true)
+		}
+	}
+
+	if decl.Body != nil {
+		if fn.Pragma&ir.Noescape != 0 {
+			base.ErrorfAt(fn.Pos(), "can only use //go:noescape with external func implementations")
+		}
+		if (fn.Pragma&ir.UintptrKeepAlive != 0 && fn.Pragma&ir.UintptrEscapes == 0) && fn.Pragma&ir.Nosplit == 0 {
+			// Stack growth can't handle uintptr arguments that may
+			// be pointers (as we don't know which are pointers
+			// when creating the stack map). Thus uintptrkeepalive
+			// functions (and all transitive callees) must be
+			// nosplit.
+			//
+			// N.B. uintptrescapes implies uintptrkeepalive but it
+			// is OK since the arguments must escape to the heap.
+			//
+			// TODO(prattmic): Add recursive nosplit check of callees.
+			// TODO(prattmic): Functions with no body (i.e.,
+			// assembly) must also be nosplit, but we can't check
+			// that here.
+			base.ErrorfAt(fn.Pos(), "go:uintptrkeepalive requires go:nosplit")
+		}
+	}
+
+	if decl.Name.Value == "init" && decl.Recv == nil {
+		g.target.Inits = append(g.target.Inits, fn)
+	}
+
+	saveHaveEmbed := g.haveEmbed
+	saveCurDecl := g.curDecl
+	g.curDecl = ""
+	g.later(func() {
+		defer func(b bool, s string) {
+			// Revert haveEmbed and curDecl back to what they were before
+			// the "later" function.
+			g.haveEmbed = b
+			g.curDecl = s
+		}(g.haveEmbed, g.curDecl)
+
+		// Set haveEmbed and curDecl to what they were for this funcDecl.
+		g.haveEmbed = saveHaveEmbed
+		g.curDecl = saveCurDecl
+		if fn.Type().HasTParam() {
+			g.topFuncIsGeneric = true
+		}
+		g.funcBody(fn, decl.Recv, decl.Type, decl.Body)
+		g.topFuncIsGeneric = false
+		if fn.Type().HasTParam() && fn.Body != nil {
+			// Set pointers to the dcls/body of a generic function/method in
+			// the Inl struct, so it is marked for export, is available for
+			// stenciling, and works with Inline_Flood().
+			fn.Inl = &ir.Inline{
+				Cost: 1,
+				Dcl:  fn.Dcl,
+				Body: fn.Body,
+			}
+		}
+
+		out.Append(fn)
+	})
+}
+
+func (g *irgen) typeDecl(out *ir.Nodes, decl *syntax.TypeDecl) {
+	// Set the position for any error messages we might print (e.g. too large types).
+	base.Pos = g.pos(decl)
+	assert(ir.CurFunc != nil || g.curDecl == "")
+	// Set g.curDecl to the type name, as context for the type params declared
+	// during types2-to-types1 translation if this is a generic type.
+	saveCurDecl := g.curDecl
+	g.curDecl = decl.Name.Value
+	if decl.Alias {
+		name, _ := g.def(decl.Name)
+		g.pragmaFlags(decl.Pragma, 0)
+		assert(name.Alias()) // should be set by irgen.obj
+
+		out.Append(ir.NewDecl(g.pos(decl), ir.ODCLTYPE, name))
+		g.curDecl = ""
+		return
+	}
+
+	// Prevent size calculations until we set the underlying type.
+	types.DeferCheckSize()
+
+	name, obj := g.def(decl.Name)
+	ntyp, otyp := name.Type(), obj.Type()
+	if ir.CurFunc != nil {
+		ntyp.SetVargen()
+	}
+
+	pragmas := g.pragmaFlags(decl.Pragma, 0)
+	name.SetPragma(pragmas) // TODO(mdempsky): Is this still needed?
+
+	ntyp.SetUnderlying(g.typeExpr(decl.Type))
+
+	tparams := otyp.(*types2.Named).TypeParams()
+	if n := tparams.Len(); n > 0 {
+		rparams := make([]*types.Type, n)
+		for i := range rparams {
+			rparams[i] = g.typ(tparams.At(i))
+		}
+		// This will set hasTParam flag if any rparams are not concrete types.
+		ntyp.SetRParams(rparams)
+	}
+	types.ResumeCheckSize()
+
+	g.curDecl = saveCurDecl
+	if otyp, ok := otyp.(*types2.Named); ok && otyp.NumMethods() != 0 {
+		methods := make([]*types.Field, otyp.NumMethods())
+		for i := range methods {
+			m := otyp.Method(i)
+			// Set g.curDecl to recvTypeName.methName, as context for the
+			// method-specific type params in the receiver.
+			g.curDecl = decl.Name.Value + "." + m.Name()
+			meth := g.obj(m)
+			methods[i] = types.NewField(meth.Pos(), g.selector(m), meth.Type())
+			methods[i].Nname = meth
+			g.curDecl = ""
+		}
+		ntyp.Methods().Set(methods)
+	}
+
+	out.Append(ir.NewDecl(g.pos(decl), ir.ODCLTYPE, name))
+}
+
+func (g *irgen) varDecl(out *ir.Nodes, decl *syntax.VarDecl) {
+	pos := g.pos(decl)
+	// Set the position for any error messages we might print (e.g. too large types).
+	base.Pos = pos
+	names := make([]*ir.Name, len(decl.NameList))
+	for i, name := range decl.NameList {
+		names[i], _ = g.def(name)
+	}
+
+	if decl.Pragma != nil {
+		pragma := decl.Pragma.(*pragmas)
+		varEmbed(g.makeXPos, names[0], decl, pragma, g.haveEmbed)
+		g.reportUnused(pragma)
+	}
+
+	haveEmbed := g.haveEmbed
+	do := func() {
+		defer func(b bool) { g.haveEmbed = b }(g.haveEmbed)
+
+		g.haveEmbed = haveEmbed
+		values := g.exprList(decl.Values)
+
+		var as2 *ir.AssignListStmt
+		if len(values) != 0 && len(names) != len(values) {
+			as2 = ir.NewAssignListStmt(pos, ir.OAS2, make([]ir.Node, len(names)), values)
+		}
+
+		for i, name := range names {
+			if ir.CurFunc != nil {
+				out.Append(ir.NewDecl(pos, ir.ODCL, name))
+			}
+			if as2 != nil {
+				as2.Lhs[i] = name
+				name.Defn = as2
+			} else {
+				as := ir.NewAssignStmt(pos, name, nil)
+				if len(values) != 0 {
+					as.Y = values[i]
+					name.Defn = as
+				} else if ir.CurFunc == nil {
+					name.Defn = as
+				}
+				if !g.delayTransform() {
+					lhs := []ir.Node{as.X}
+					rhs := []ir.Node{}
+					if as.Y != nil {
+						rhs = []ir.Node{as.Y}
+					}
+					transformAssign(as, lhs, rhs)
+					as.X = lhs[0]
+					if as.Y != nil {
+						as.Y = rhs[0]
+					}
+				}
+				as.SetTypecheck(1)
+				out.Append(as)
+			}
+		}
+		if as2 != nil {
+			if !g.delayTransform() {
+				transformAssign(as2, as2.Lhs, as2.Rhs)
+			}
+			as2.SetTypecheck(1)
+			out.Append(as2)
+		}
+	}
+
+	// If we're within a function, we need to process the assignment
+	// part of the variable declaration right away. Otherwise, we leave
+	// it to be handled after all top-level declarations are processed.
+	if ir.CurFunc != nil {
+		do()
+	} else {
+		g.later(do)
+	}
+}
+
+// pragmaFlags returns any specified pragma flags included in allowed,
+// and reports errors about any other, unexpected pragmas.
+func (g *irgen) pragmaFlags(pragma syntax.Pragma, allowed ir.PragmaFlag) ir.PragmaFlag {
+	if pragma == nil {
+		return 0
+	}
+	p := pragma.(*pragmas)
+	present := p.Flag & allowed
+	p.Flag &^= allowed
+	g.reportUnused(p)
+	return present
+}
+
+// reportUnused reports errors about any unused pragmas.
+func (g *irgen) reportUnused(pragma *pragmas) {
+	for _, pos := range pragma.Pos {
+		if pos.Flag&pragma.Flag != 0 {
+			base.ErrorfAt(g.makeXPos(pos.Pos), "misplaced compiler directive")
+		}
+	}
+	if len(pragma.Embeds) > 0 {
+		for _, e := range pragma.Embeds {
+			base.ErrorfAt(g.makeXPos(e.Pos), "misplaced go:embed directive")
+		}
+	}
+}
diff --git a/src/cmd/compile/internal/noder/export.go b/src/cmd/compile/internal/noder/export.go
new file mode 100644
index 0000000..263cdc2
--- /dev/null
+++ b/src/cmd/compile/internal/noder/export.go
@@ -0,0 +1,35 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/typecheck"
+	"cmd/internal/bio"
+)
+
+func WriteExports(out *bio.Writer) {
+	var data bytes.Buffer
+
+	if base.Debug.Unified != 0 {
+		data.WriteByte('u')
+		writeUnifiedExport(&data)
+	} else {
+		typecheck.WriteExports(&data, true)
+	}
+
+	// The linker also looks for the $$ marker - use char after $$ to distinguish format.
+	out.WriteString("\n$$B\n") // indicate binary export format
+	io.Copy(out, &data)
+	out.WriteString("\n$$\n")
+
+	if base.Debug.Export != 0 {
+		fmt.Printf("BenchmarkExportSize:%s 1 %d bytes\n", base.Ctxt.Pkgpath, data.Len())
+	}
+}
diff --git a/src/cmd/compile/internal/noder/expr.go b/src/cmd/compile/internal/noder/expr.go
new file mode 100644
index 0000000..f391339
--- /dev/null
+++ b/src/cmd/compile/internal/noder/expr.go
@@ -0,0 +1,474 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+	"cmd/internal/src"
+)
+
+func (g *irgen) expr(expr syntax.Expr) ir.Node {
+	expr = unparen(expr) // skip parens; unneeded after parse+typecheck
+
+	if expr == nil {
+		return nil
+	}
+
+	if expr, ok := expr.(*syntax.Name); ok && expr.Value == "_" {
+		return ir.BlankNode
+	}
+
+	tv := g.typeAndValue(expr)
+	switch {
+	case tv.IsBuiltin():
+		// Qualified builtins, such as unsafe.Add and unsafe.Slice.
+		if expr, ok := expr.(*syntax.SelectorExpr); ok {
+			if name, ok := expr.X.(*syntax.Name); ok {
+				if _, ok := g.info.Uses[name].(*types2.PkgName); ok {
+					return g.use(expr.Sel)
+				}
+			}
+		}
+		return g.use(expr.(*syntax.Name))
+	case tv.IsType():
+		return ir.TypeNode(g.typ(tv.Type))
+	case tv.IsValue(), tv.IsVoid():
+		// ok
+	default:
+		base.FatalfAt(g.pos(expr), "unrecognized type-checker result")
+	}
+
+	base.Assert(g.exprStmtOK)
+
+	typ := idealType(tv)
+	if typ == nil {
+		base.FatalfAt(g.pos(expr), "unexpected untyped type: %v", tv.Type)
+	}
+
+	// Constant expression.
+	if tv.Value != nil {
+		typ := g.typ(typ)
+		value := FixValue(typ, tv.Value)
+		return OrigConst(g.pos(expr), typ, value, constExprOp(expr), syntax.String(expr))
+	}
+
+	n := g.expr0(typ, expr)
+	if n.Typecheck() != 1 && n.Typecheck() != 3 {
+		base.FatalfAt(g.pos(expr), "missed typecheck: %+v", n)
+	}
+	if n.Op() != ir.OFUNCINST && !g.match(n.Type(), typ, tv.HasOk()) {
+		base.FatalfAt(g.pos(expr), "expected %L to have type %v", n, typ)
+	}
+	return n
+}
+
+func (g *irgen) expr0(typ types2.Type, expr syntax.Expr) ir.Node {
+	pos := g.pos(expr)
+	assert(pos.IsKnown())
+
+	// Set base.Pos for transformation code that still uses base.Pos, rather than
+	// the pos of the node being converted.
+	base.Pos = pos
+
+	switch expr := expr.(type) {
+	case *syntax.Name:
+		if _, isNil := g.info.Uses[expr].(*types2.Nil); isNil {
+			return Nil(pos, g.typ(typ))
+		}
+		return g.use(expr)
+
+	case *syntax.CompositeLit:
+		return g.compLit(typ, expr)
+
+	case *syntax.FuncLit:
+		return g.funcLit(typ, expr)
+
+	case *syntax.AssertExpr:
+		return Assert(pos, g.expr(expr.X), g.typeExpr(expr.Type))
+
+	case *syntax.CallExpr:
+		fun := g.expr(expr.Fun)
+		return g.callExpr(pos, g.typ(typ), fun, g.exprs(expr.ArgList), expr.HasDots)
+
+	case *syntax.IndexExpr:
+		args := unpackListExpr(expr.Index)
+		if len(args) == 1 {
+			tv := g.typeAndValue(args[0])
+			if tv.IsValue() {
+				// This is just a normal index expression
+				n := Index(pos, g.typ(typ), g.expr(expr.X), g.expr(args[0]))
+				if !g.delayTransform() {
+					// transformIndex will modify n.Type() for OINDEXMAP.
+					transformIndex(n)
+				}
+				return n
+			}
+		}
+
+		// expr.Index is a list of type args, so we ignore it, since types2 has
+		// already provided this info with the Info.Instances map.
+		return g.expr(expr.X)
+
+	case *syntax.SelectorExpr:
+		// Qualified identifier.
+		if name, ok := expr.X.(*syntax.Name); ok {
+			if _, ok := g.info.Uses[name].(*types2.PkgName); ok {
+				return g.use(expr.Sel)
+			}
+		}
+		return g.selectorExpr(pos, typ, expr)
+
+	case *syntax.SliceExpr:
+		n := Slice(pos, g.typ(typ), g.expr(expr.X), g.expr(expr.Index[0]), g.expr(expr.Index[1]), g.expr(expr.Index[2]))
+		if !g.delayTransform() {
+			transformSlice(n)
+		}
+		return n
+
+	case *syntax.Operation:
+		if expr.Y == nil {
+			n := Unary(pos, g.typ(typ), g.op(expr.Op, unOps[:]), g.expr(expr.X))
+			if n.Op() == ir.OADDR && !g.delayTransform() {
+				transformAddr(n.(*ir.AddrExpr))
+			}
+			return n
+		}
+		switch op := g.op(expr.Op, binOps[:]); op {
+		case ir.OEQ, ir.ONE, ir.OLT, ir.OLE, ir.OGT, ir.OGE:
+			n := Compare(pos, g.typ(typ), op, g.expr(expr.X), g.expr(expr.Y))
+			if !g.delayTransform() {
+				transformCompare(n)
+			}
+			return n
+		case ir.OANDAND, ir.OOROR:
+			x := g.expr(expr.X)
+			y := g.expr(expr.Y)
+			return typed(x.Type(), ir.NewLogicalExpr(pos, op, x, y))
+		default:
+			n := Binary(pos, op, g.typ(typ), g.expr(expr.X), g.expr(expr.Y))
+			if op == ir.OADD && !g.delayTransform() {
+				return transformAdd(n)
+			}
+			return n
+		}
+
+	default:
+		g.unhandled("expression", expr)
+		panic("unreachable")
+	}
+}
+
+// substType does a normal type substition, but tparams is in the form of a field
+// list, and targs is in terms of a slice of type nodes. substType records any newly
+// instantiated types into g.instTypeList.
+func (g *irgen) substType(typ *types.Type, tparams *types.Type, targs []ir.Ntype) *types.Type {
+	fields := tparams.FieldSlice()
+	tparams1 := make([]*types.Type, len(fields))
+	for i, f := range fields {
+		tparams1[i] = f.Type
+	}
+	targs1 := make([]*types.Type, len(targs))
+	for i, n := range targs {
+		targs1[i] = n.Type()
+	}
+	ts := typecheck.Tsubster{
+		Tparams: tparams1,
+		Targs:   targs1,
+	}
+	newt := ts.Typ(typ)
+	return newt
+}
+
+// callExpr creates a call expression (which might be a type conversion, built-in
+// call, or a regular call) and does standard transforms, unless we are in a generic
+// function.
+func (g *irgen) callExpr(pos src.XPos, typ *types.Type, fun ir.Node, args []ir.Node, dots bool) ir.Node {
+	n := ir.NewCallExpr(pos, ir.OCALL, fun, args)
+	n.IsDDD = dots
+	typed(typ, n)
+
+	if fun.Op() == ir.OTYPE {
+		// Actually a type conversion, not a function call.
+		if !g.delayTransform() {
+			return transformConvCall(n)
+		}
+		return n
+	}
+
+	if fun, ok := fun.(*ir.Name); ok && fun.BuiltinOp != 0 {
+		if !g.delayTransform() {
+			return transformBuiltin(n)
+		}
+		return n
+	}
+
+	// Add information, now that we know that fun is actually being called.
+	switch fun := fun.(type) {
+	case *ir.SelectorExpr:
+		if fun.Op() == ir.OMETHVALUE {
+			op := ir.ODOTMETH
+			if fun.X.Type().IsInterface() {
+				op = ir.ODOTINTER
+			}
+			fun.SetOp(op)
+			// Set the type to include the receiver, since that's what
+			// later parts of the compiler expect
+			fun.SetType(fun.Selection.Type)
+		}
+	}
+
+	// A function instantiation (even if fully concrete) shouldn't be
+	// transformed yet, because we need to add the dictionary during the
+	// transformation.
+	if fun.Op() != ir.OFUNCINST && !g.delayTransform() {
+		transformCall(n)
+	}
+	return n
+}
+
+// selectorExpr resolves the choice of ODOT, ODOTPTR, OMETHVALUE (eventually
+// ODOTMETH & ODOTINTER), and OMETHEXPR and deals with embedded fields here rather
+// than in typecheck.go.
+func (g *irgen) selectorExpr(pos src.XPos, typ types2.Type, expr *syntax.SelectorExpr) ir.Node {
+	x := g.expr(expr.X)
+	if x.Type().HasTParam() {
+		// Leave a method call on a type param as an OXDOT, since it can
+		// only be fully transformed once it has an instantiated type.
+		n := ir.NewSelectorExpr(pos, ir.OXDOT, x, typecheck.Lookup(expr.Sel.Value))
+		typed(g.typ(typ), n)
+		return n
+	}
+
+	selinfo := g.info.Selections[expr]
+	// Everything up to the last selection is an implicit embedded field access,
+	// and the last selection is determined by selinfo.Kind().
+	index := selinfo.Index()
+	embeds, last := index[:len(index)-1], index[len(index)-1]
+
+	origx := x
+	for _, ix := range embeds {
+		x = Implicit(DotField(pos, x, ix))
+	}
+
+	kind := selinfo.Kind()
+	if kind == types2.FieldVal {
+		return DotField(pos, x, last)
+	}
+
+	var n ir.Node
+	method2 := selinfo.Obj().(*types2.Func)
+
+	if kind == types2.MethodExpr {
+		// OMETHEXPR is unusual in using directly the node and type of the
+		// original OTYPE node (origx) before passing through embedded
+		// fields, even though the method is selected from the type
+		// (x.Type()) reached after following the embedded fields. We will
+		// actually drop any ODOT nodes we created due to the embedded
+		// fields.
+		n = MethodExpr(pos, origx, x.Type(), last)
+	} else {
+		// Add implicit addr/deref for method values, if needed.
+		if x.Type().IsInterface() {
+			n = DotMethod(pos, x, last)
+		} else {
+			recvType2 := method2.Type().(*types2.Signature).Recv().Type()
+			_, wantPtr := recvType2.(*types2.Pointer)
+			havePtr := x.Type().IsPtr()
+
+			if havePtr != wantPtr {
+				if havePtr {
+					x = Implicit(Deref(pos, x.Type().Elem(), x))
+				} else {
+					x = Implicit(Addr(pos, x))
+				}
+			}
+			recvType2Base := recvType2
+			if wantPtr {
+				recvType2Base = types2.AsPointer(recvType2).Elem()
+			}
+			if recvType2Base.(*types2.Named).TypeParams().Len() > 0 {
+				// recvType2 is the original generic type that is
+				// instantiated for this method call.
+				// selinfo.Recv() is the instantiated type
+				recvType2 = recvType2Base
+				recvTypeSym := g.pkg(method2.Pkg()).Lookup(recvType2.(*types2.Named).Obj().Name())
+				recvType := recvTypeSym.Def.(*ir.Name).Type()
+				// method is the generic method associated with
+				// the base generic type. The instantiated type may not
+				// have method bodies filled in, if it was imported.
+				method := recvType.Methods().Index(last).Nname.(*ir.Name)
+				n = ir.NewSelectorExpr(pos, ir.OMETHVALUE, x, typecheck.Lookup(expr.Sel.Value))
+				n.(*ir.SelectorExpr).Selection = types.NewField(pos, method.Sym(), method.Type())
+				n.(*ir.SelectorExpr).Selection.Nname = method
+				typed(method.Type(), n)
+
+				xt := deref(x.Type())
+				targs := make([]ir.Ntype, len(xt.RParams()))
+				for i := range targs {
+					targs[i] = ir.TypeNode(xt.RParams()[i])
+				}
+
+				// Create function instantiation with the type
+				// args for the receiver type for the method call.
+				n = ir.NewInstExpr(pos, ir.OFUNCINST, n, targs)
+				typed(g.typ(typ), n)
+				return n
+			}
+
+			if !g.match(x.Type(), recvType2, false) {
+				base.FatalfAt(pos, "expected %L to have type %v", x, recvType2)
+			} else {
+				n = DotMethod(pos, x, last)
+			}
+		}
+	}
+	if have, want := n.Sym(), g.selector(method2); have != want {
+		base.FatalfAt(pos, "bad Sym: have %v, want %v", have, want)
+	}
+	return n
+}
+
+func (g *irgen) exprList(expr syntax.Expr) []ir.Node {
+	return g.exprs(unpackListExpr(expr))
+}
+
+func unpackListExpr(expr syntax.Expr) []syntax.Expr {
+	switch expr := expr.(type) {
+	case nil:
+		return nil
+	case *syntax.ListExpr:
+		return expr.ElemList
+	default:
+		return []syntax.Expr{expr}
+	}
+}
+
+func (g *irgen) exprs(exprs []syntax.Expr) []ir.Node {
+	nodes := make([]ir.Node, len(exprs))
+	for i, expr := range exprs {
+		nodes[i] = g.expr(expr)
+	}
+	return nodes
+}
+
+func (g *irgen) compLit(typ types2.Type, lit *syntax.CompositeLit) ir.Node {
+	if ptr, ok := types2.CoreType(typ).(*types2.Pointer); ok {
+		n := ir.NewAddrExpr(g.pos(lit), g.compLit(ptr.Elem(), lit))
+		n.SetOp(ir.OPTRLIT)
+		return typed(g.typ(typ), n)
+	}
+
+	_, isStruct := types2.CoreType(typ).(*types2.Struct)
+
+	exprs := make([]ir.Node, len(lit.ElemList))
+	for i, elem := range lit.ElemList {
+		switch elem := elem.(type) {
+		case *syntax.KeyValueExpr:
+			var key ir.Node
+			if isStruct {
+				key = ir.NewIdent(g.pos(elem.Key), g.name(elem.Key.(*syntax.Name)))
+			} else {
+				key = g.expr(elem.Key)
+			}
+			value := wrapname(g.pos(elem.Value), g.expr(elem.Value))
+			if value.Op() == ir.OPAREN {
+				// Make sure any PAREN node added by wrapper has a type
+				typed(value.(*ir.ParenExpr).X.Type(), value)
+			}
+			exprs[i] = ir.NewKeyExpr(g.pos(elem), key, value)
+		default:
+			exprs[i] = wrapname(g.pos(elem), g.expr(elem))
+			if exprs[i].Op() == ir.OPAREN {
+				// Make sure any PAREN node added by wrapper has a type
+				typed(exprs[i].(*ir.ParenExpr).X.Type(), exprs[i])
+			}
+		}
+	}
+
+	n := ir.NewCompLitExpr(g.pos(lit), ir.OCOMPLIT, nil, exprs)
+	typed(g.typ(typ), n)
+	var r ir.Node = n
+	if !g.delayTransform() {
+		r = transformCompLit(n)
+	}
+	return r
+}
+
+func (g *irgen) funcLit(typ2 types2.Type, expr *syntax.FuncLit) ir.Node {
+	fn := ir.NewClosureFunc(g.pos(expr), ir.CurFunc != nil)
+	ir.NameClosure(fn.OClosure, ir.CurFunc)
+
+	typ := g.typ(typ2)
+	typed(typ, fn.Nname)
+	typed(typ, fn.OClosure)
+	fn.SetTypecheck(1)
+
+	g.funcBody(fn, nil, expr.Type, expr.Body)
+
+	ir.FinishCaptureNames(fn.Pos(), ir.CurFunc, fn)
+
+	// TODO(mdempsky): ir.CaptureName should probably handle
+	// copying these fields from the canonical variable.
+	for _, cv := range fn.ClosureVars {
+		cv.SetType(cv.Canonical().Type())
+		cv.SetTypecheck(1)
+	}
+
+	if g.topFuncIsGeneric {
+		// Don't add any closure inside a generic function/method to the
+		// g.target.Decls list, even though it may not be generic itself.
+		// See issue #47514.
+		return ir.UseClosure(fn.OClosure, nil)
+	} else {
+		return ir.UseClosure(fn.OClosure, g.target)
+	}
+}
+
+func (g *irgen) typeExpr(typ syntax.Expr) *types.Type {
+	n := g.expr(typ)
+	if n.Op() != ir.OTYPE {
+		base.FatalfAt(g.pos(typ), "expected type: %L", n)
+	}
+	return n.Type()
+}
+
+// constExprOp returns an ir.Op that represents the outermost
+// operation of the given constant expression. It's intended for use
+// with ir.RawOrigExpr.
+func constExprOp(expr syntax.Expr) ir.Op {
+	switch expr := expr.(type) {
+	default:
+		panic(fmt.Sprintf("%s: unexpected expression: %T", expr.Pos(), expr))
+
+	case *syntax.BasicLit:
+		return ir.OLITERAL
+	case *syntax.Name, *syntax.SelectorExpr:
+		return ir.ONAME
+	case *syntax.CallExpr:
+		return ir.OCALL
+	case *syntax.Operation:
+		if expr.Y == nil {
+			return unOps[expr.Op]
+		}
+		return binOps[expr.Op]
+	}
+}
+
+func unparen(expr syntax.Expr) syntax.Expr {
+	for {
+		paren, ok := expr.(*syntax.ParenExpr)
+		if !ok {
+			return expr
+		}
+		expr = paren.X
+	}
+}
diff --git a/src/cmd/compile/internal/noder/func.go b/src/cmd/compile/internal/noder/func.go
new file mode 100644
index 0000000..6077b34
--- /dev/null
+++ b/src/cmd/compile/internal/noder/func.go
@@ -0,0 +1,73 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/internal/src"
+)
+
+func (g *irgen) funcBody(fn *ir.Func, recv *syntax.Field, sig *syntax.FuncType, block *syntax.BlockStmt) {
+	typecheck.Func(fn)
+
+	// TODO(mdempsky): Remove uses of ir.CurFunc and
+	// typecheck.DeclContext after we stop relying on typecheck
+	// for desugaring.
+	outerfn, outerctxt := ir.CurFunc, typecheck.DeclContext
+	ir.CurFunc = fn
+
+	typ := fn.Type()
+	if param := typ.Recv(); param != nil {
+		g.defParam(param, recv, ir.PPARAM)
+	}
+	for i, param := range typ.Params().FieldSlice() {
+		g.defParam(param, sig.ParamList[i], ir.PPARAM)
+	}
+	for i, result := range typ.Results().FieldSlice() {
+		g.defParam(result, sig.ResultList[i], ir.PPARAMOUT)
+	}
+
+	// We may have type-checked a call to this function already and
+	// calculated its size, including parameter offsets. Now that we've
+	// created the parameter Names, force a recalculation to ensure
+	// their offsets are correct.
+	types.RecalcSize(typ)
+
+	if block != nil {
+		typecheck.DeclContext = ir.PAUTO
+
+		fn.Body = g.stmts(block.List)
+		if fn.Body == nil {
+			fn.Body = []ir.Node{ir.NewBlockStmt(src.NoXPos, nil)}
+		}
+		fn.Endlineno = g.makeXPos(block.Rbrace)
+
+		if base.Flag.Dwarf {
+			g.recordScopes(fn, sig)
+		}
+	}
+
+	ir.CurFunc, typecheck.DeclContext = outerfn, outerctxt
+}
+
+func (g *irgen) defParam(param *types.Field, decl *syntax.Field, class ir.Class) {
+	typecheck.DeclContext = class
+
+	var name *ir.Name
+	if decl.Name != nil {
+		name, _ = g.def(decl.Name)
+	} else if class == ir.PPARAMOUT {
+		name = g.obj(g.info.Implicits[decl])
+	}
+
+	if name != nil {
+		param.Nname = name
+		param.Sym = name.Sym() // in case it was renamed
+	}
+}
diff --git a/src/cmd/compile/internal/noder/helpers.go b/src/cmd/compile/internal/noder/helpers.go
new file mode 100644
index 0000000..4ef46a4
--- /dev/null
+++ b/src/cmd/compile/internal/noder/helpers.go
@@ -0,0 +1,284 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"go/constant"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+	"cmd/internal/src"
+)
+
+// Helpers for constructing typed IR nodes.
+//
+// TODO(mdempsky): Move into their own package so they can be easily
+// reused by iimport and frontend optimizations.
+
+type ImplicitNode interface {
+	ir.Node
+	SetImplicit(x bool)
+}
+
+// Implicit returns n after marking it as Implicit.
+func Implicit(n ImplicitNode) ImplicitNode {
+	n.SetImplicit(true)
+	return n
+}
+
+// typed returns n after setting its type to typ.
+func typed(typ *types.Type, n ir.Node) ir.Node {
+	n.SetType(typ)
+	n.SetTypecheck(1)
+	return n
+}
+
+// Values
+
+func OrigConst(pos src.XPos, typ *types.Type, val constant.Value, op ir.Op, raw string) ir.Node {
+	orig := ir.NewRawOrigExpr(pos, op, raw)
+	return ir.NewConstExpr(val, typed(typ, orig))
+}
+
+// FixValue returns val after converting and truncating it as
+// appropriate for typ.
+func FixValue(typ *types.Type, val constant.Value) constant.Value {
+	assert(typ.Kind() != types.TFORW)
+	switch {
+	case typ.IsInteger():
+		val = constant.ToInt(val)
+	case typ.IsFloat():
+		val = constant.ToFloat(val)
+	case typ.IsComplex():
+		val = constant.ToComplex(val)
+	}
+	if !typ.IsUntyped() {
+		val = typecheck.DefaultLit(ir.NewBasicLit(src.NoXPos, val), typ).Val()
+	}
+	if !typ.IsTypeParam() {
+		ir.AssertValidTypeForConst(typ, val)
+	}
+	return val
+}
+
+func Nil(pos src.XPos, typ *types.Type) ir.Node {
+	return typed(typ, ir.NewNilExpr(pos))
+}
+
+// Expressions
+
+func Addr(pos src.XPos, x ir.Node) *ir.AddrExpr {
+	n := typecheck.NodAddrAt(pos, x)
+	typed(types.NewPtr(x.Type()), n)
+	return n
+}
+
+func Assert(pos src.XPos, x ir.Node, typ *types.Type) ir.Node {
+	return typed(typ, ir.NewTypeAssertExpr(pos, x, nil))
+}
+
+func Binary(pos src.XPos, op ir.Op, typ *types.Type, x, y ir.Node) *ir.BinaryExpr {
+	switch op {
+	case ir.OADD:
+		n := ir.NewBinaryExpr(pos, op, x, y)
+		typed(typ, n)
+		return n
+	default:
+		n := ir.NewBinaryExpr(pos, op, x, y)
+		typed(x.Type(), n)
+		return n
+	}
+}
+
+func Compare(pos src.XPos, typ *types.Type, op ir.Op, x, y ir.Node) *ir.BinaryExpr {
+	n := ir.NewBinaryExpr(pos, op, x, y)
+	typed(typ, n)
+	return n
+}
+
+func Deref(pos src.XPos, typ *types.Type, x ir.Node) *ir.StarExpr {
+	n := ir.NewStarExpr(pos, x)
+	typed(typ, n)
+	return n
+}
+
+func DotField(pos src.XPos, x ir.Node, index int) *ir.SelectorExpr {
+	op, typ := ir.ODOT, x.Type()
+	if typ.IsPtr() {
+		op, typ = ir.ODOTPTR, typ.Elem()
+	}
+	if !typ.IsStruct() {
+		base.FatalfAt(pos, "DotField of non-struct: %L", x)
+	}
+
+	// TODO(mdempsky): This is the backend's responsibility.
+	types.CalcSize(typ)
+
+	field := typ.Field(index)
+	return dot(pos, field.Type, op, x, field)
+}
+
+func DotMethod(pos src.XPos, x ir.Node, index int) *ir.SelectorExpr {
+	method := method(x.Type(), index)
+
+	// Method value.
+	typ := typecheck.NewMethodType(method.Type, nil)
+	return dot(pos, typ, ir.OMETHVALUE, x, method)
+}
+
+// MethodExpr returns a OMETHEXPR node with the indicated index into the methods
+// of typ. The receiver type is set from recv, which is different from typ if the
+// method was accessed via embedded fields. Similarly, the X value of the
+// ir.SelectorExpr is recv, the original OTYPE node before passing through the
+// embedded fields.
+func MethodExpr(pos src.XPos, recv ir.Node, embed *types.Type, index int) *ir.SelectorExpr {
+	method := method(embed, index)
+	typ := typecheck.NewMethodType(method.Type, recv.Type())
+	// The method expression T.m requires a wrapper when T
+	// is different from m's declared receiver type. We
+	// normally generate these wrappers while writing out
+	// runtime type descriptors, which is always done for
+	// types declared at package scope. However, we need
+	// to make sure to generate wrappers for anonymous
+	// receiver types too.
+	if recv.Sym() == nil {
+		typecheck.NeedRuntimeType(recv.Type())
+	}
+	return dot(pos, typ, ir.OMETHEXPR, recv, method)
+}
+
+func dot(pos src.XPos, typ *types.Type, op ir.Op, x ir.Node, selection *types.Field) *ir.SelectorExpr {
+	n := ir.NewSelectorExpr(pos, op, x, selection.Sym)
+	n.Selection = selection
+	typed(typ, n)
+	return n
+}
+
+// TODO(mdempsky): Move to package types.
+func method(typ *types.Type, index int) *types.Field {
+	if typ.IsInterface() {
+		return typ.AllMethods().Index(index)
+	}
+	return types.ReceiverBaseType(typ).Methods().Index(index)
+}
+
+func Index(pos src.XPos, typ *types.Type, x, index ir.Node) *ir.IndexExpr {
+	n := ir.NewIndexExpr(pos, x, index)
+	typed(typ, n)
+	return n
+}
+
+func Slice(pos src.XPos, typ *types.Type, x, low, high, max ir.Node) *ir.SliceExpr {
+	op := ir.OSLICE
+	if max != nil {
+		op = ir.OSLICE3
+	}
+	n := ir.NewSliceExpr(pos, op, x, low, high, max)
+	typed(typ, n)
+	return n
+}
+
+func Unary(pos src.XPos, typ *types.Type, op ir.Op, x ir.Node) ir.Node {
+	switch op {
+	case ir.OADDR:
+		return Addr(pos, x)
+	case ir.ODEREF:
+		return Deref(pos, typ, x)
+	}
+
+	if op == ir.ORECV {
+		if typ.IsFuncArgStruct() && typ.NumFields() == 2 {
+			// Remove the second boolean type (if provided by type2),
+			// since that works better with the rest of the compiler
+			// (which will add it back in later).
+			assert(typ.Field(1).Type.Kind() == types.TBOOL)
+			typ = typ.Field(0).Type
+		}
+	}
+	return typed(typ, ir.NewUnaryExpr(pos, op, x))
+}
+
+// Statements
+
+var one = constant.MakeInt64(1)
+
+func IncDec(pos src.XPos, op ir.Op, x ir.Node) *ir.AssignOpStmt {
+	assert(x.Type() != nil)
+	bl := ir.NewBasicLit(pos, one)
+	if x.Type().HasTParam() {
+		// If the operand is generic, then types2 will have proved it must be
+		// a type that fits with increment/decrement, so just set the type of
+		// "one" to n.Type(). This works even for types that are eventually
+		// float or complex.
+		typed(x.Type(), bl)
+	} else {
+		bl = typecheck.DefaultLit(bl, x.Type())
+	}
+	return ir.NewAssignOpStmt(pos, op, x, bl)
+}
+
+func idealType(tv syntax.TypeAndValue) types2.Type {
+	// The gc backend expects all expressions to have a concrete type, and
+	// types2 mostly satisfies this expectation already. But there are a few
+	// cases where the Go spec doesn't require converting to concrete type,
+	// and so types2 leaves them untyped. So we need to fix those up here.
+	typ := tv.Type
+	if basic, ok := typ.(*types2.Basic); ok && basic.Info()&types2.IsUntyped != 0 {
+		switch basic.Kind() {
+		case types2.UntypedNil:
+			// ok; can appear in type switch case clauses
+			// TODO(mdempsky): Handle as part of type switches instead?
+		case types2.UntypedInt, types2.UntypedFloat, types2.UntypedComplex:
+			// Untyped rhs of non-constant shift, e.g. x << 1.0.
+			// If we have a constant value, it must be an int >= 0.
+			if tv.Value != nil {
+				s := constant.ToInt(tv.Value)
+				assert(s.Kind() == constant.Int && constant.Sign(s) >= 0)
+			}
+			typ = types2.Typ[types2.Uint]
+		case types2.UntypedBool:
+			typ = types2.Typ[types2.Bool] // expression in "if" or "for" condition
+		case types2.UntypedString:
+			typ = types2.Typ[types2.String] // argument to "append" or "copy" calls
+		default:
+			return nil
+		}
+	}
+	return typ
+}
+
+func isTypeParam(t types2.Type) bool {
+	_, ok := t.(*types2.TypeParam)
+	return ok
+}
+
+// isNotInHeap reports whether typ is or contains an element of type
+// runtime/internal/sys.NotInHeap.
+func isNotInHeap(typ types2.Type) bool {
+	if named, ok := typ.(*types2.Named); ok {
+		if obj := named.Obj(); obj.Name() == "nih" && obj.Pkg().Path() == "runtime/internal/sys" {
+			return true
+		}
+		typ = named.Underlying()
+	}
+
+	switch typ := typ.(type) {
+	case *types2.Array:
+		return isNotInHeap(typ.Elem())
+	case *types2.Struct:
+		for i := 0; i < typ.NumFields(); i++ {
+			if isNotInHeap(typ.Field(i).Type()) {
+				return true
+			}
+		}
+		return false
+	default:
+		return false
+	}
+}
diff --git a/src/cmd/compile/internal/noder/import.go b/src/cmd/compile/internal/noder/import.go
new file mode 100644
index 0000000..8b017ec
--- /dev/null
+++ b/src/cmd/compile/internal/noder/import.go
@@ -0,0 +1,389 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"errors"
+	"fmt"
+	"internal/buildcfg"
+	"internal/pkgbits"
+	"os"
+	pathpkg "path"
+	"runtime"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/importer"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+	"cmd/internal/archive"
+	"cmd/internal/bio"
+	"cmd/internal/goobj"
+	"cmd/internal/objabi"
+)
+
+type gcimports struct {
+	ctxt     *types2.Context
+	packages map[string]*types2.Package
+}
+
+func (m *gcimports) Import(path string) (*types2.Package, error) {
+	return m.ImportFrom(path, "" /* no vendoring */, 0)
+}
+
+func (m *gcimports) ImportFrom(path, srcDir string, mode types2.ImportMode) (*types2.Package, error) {
+	if mode != 0 {
+		panic("mode must be 0")
+	}
+
+	_, pkg, err := readImportFile(path, typecheck.Target, m.ctxt, m.packages)
+	return pkg, err
+}
+
+func isDriveLetter(b byte) bool {
+	return 'a' <= b && b <= 'z' || 'A' <= b && b <= 'Z'
+}
+
+// is this path a local name? begins with ./ or ../ or /
+func islocalname(name string) bool {
+	return strings.HasPrefix(name, "/") ||
+		runtime.GOOS == "windows" && len(name) >= 3 && isDriveLetter(name[0]) && name[1] == ':' && name[2] == '/' ||
+		strings.HasPrefix(name, "./") || name == "." ||
+		strings.HasPrefix(name, "../") || name == ".."
+}
+
+func openPackage(path string) (*os.File, error) {
+	if islocalname(path) {
+		if base.Flag.NoLocalImports {
+			return nil, errors.New("local imports disallowed")
+		}
+
+		if base.Flag.Cfg.PackageFile != nil {
+			return os.Open(base.Flag.Cfg.PackageFile[path])
+		}
+
+		// try .a before .o.  important for building libraries:
+		// if there is an array.o in the array.a library,
+		// want to find all of array.a, not just array.o.
+		if file, err := os.Open(fmt.Sprintf("%s.a", path)); err == nil {
+			return file, nil
+		}
+		if file, err := os.Open(fmt.Sprintf("%s.o", path)); err == nil {
+			return file, nil
+		}
+		return nil, errors.New("file not found")
+	}
+
+	// local imports should be canonicalized already.
+	// don't want to see "encoding/../encoding/base64"
+	// as different from "encoding/base64".
+	if q := pathpkg.Clean(path); q != path {
+		return nil, fmt.Errorf("non-canonical import path %q (should be %q)", path, q)
+	}
+
+	if base.Flag.Cfg.PackageFile != nil {
+		return os.Open(base.Flag.Cfg.PackageFile[path])
+	}
+
+	for _, dir := range base.Flag.Cfg.ImportDirs {
+		if file, err := os.Open(fmt.Sprintf("%s/%s.a", dir, path)); err == nil {
+			return file, nil
+		}
+		if file, err := os.Open(fmt.Sprintf("%s/%s.o", dir, path)); err == nil {
+			return file, nil
+		}
+	}
+
+	if buildcfg.GOROOT != "" {
+		suffix := ""
+		if base.Flag.InstallSuffix != "" {
+			suffix = "_" + base.Flag.InstallSuffix
+		} else if base.Flag.Race {
+			suffix = "_race"
+		} else if base.Flag.MSan {
+			suffix = "_msan"
+		} else if base.Flag.ASan {
+			suffix = "_asan"
+		}
+
+		if file, err := os.Open(fmt.Sprintf("%s/pkg/%s_%s%s/%s.a", buildcfg.GOROOT, buildcfg.GOOS, buildcfg.GOARCH, suffix, path)); err == nil {
+			return file, nil
+		}
+		if file, err := os.Open(fmt.Sprintf("%s/pkg/%s_%s%s/%s.o", buildcfg.GOROOT, buildcfg.GOOS, buildcfg.GOARCH, suffix, path)); err == nil {
+			return file, nil
+		}
+	}
+	return nil, errors.New("file not found")
+}
+
+// resolveImportPath resolves an import path as it appears in a Go
+// source file to the package's full path.
+func resolveImportPath(path string) (string, error) {
+	// The package name main is no longer reserved,
+	// but we reserve the import path "main" to identify
+	// the main package, just as we reserve the import
+	// path "math" to identify the standard math package.
+	if path == "main" {
+		return "", errors.New("cannot import \"main\"")
+	}
+
+	if base.Ctxt.Pkgpath != "" && path == base.Ctxt.Pkgpath {
+		return "", fmt.Errorf("import %q while compiling that package (import cycle)", path)
+	}
+
+	if mapped, ok := base.Flag.Cfg.ImportMap[path]; ok {
+		path = mapped
+	}
+
+	if islocalname(path) {
+		if path[0] == '/' {
+			return "", errors.New("import path cannot be absolute path")
+		}
+
+		prefix := base.Flag.D
+		if prefix == "" {
+			// Questionable, but when -D isn't specified, historically we
+			// resolve local import paths relative to the directory the
+			// compiler's current directory, not the respective source
+			// file's directory.
+			prefix = base.Ctxt.Pathname
+		}
+		path = pathpkg.Join(prefix, path)
+
+		if err := checkImportPath(path, true); err != nil {
+			return "", err
+		}
+	}
+
+	return path, nil
+}
+
+// readImportFile reads the import file for the given package path and
+// returns its types.Pkg representation. If packages is non-nil, the
+// types2.Package representation is also returned.
+func readImportFile(path string, target *ir.Package, env *types2.Context, packages map[string]*types2.Package) (pkg1 *types.Pkg, pkg2 *types2.Package, err error) {
+	path, err = resolveImportPath(path)
+	if err != nil {
+		return
+	}
+
+	if path == "unsafe" {
+		pkg1, pkg2 = types.UnsafePkg, types2.Unsafe
+
+		// TODO(mdempsky): Investigate if this actually matters. Why would
+		// the linker or runtime care whether a package imported unsafe?
+		if !pkg1.Direct {
+			pkg1.Direct = true
+			target.Imports = append(target.Imports, pkg1)
+		}
+
+		return
+	}
+
+	pkg1 = types.NewPkg(path, "")
+	if packages != nil {
+		pkg2 = packages[path]
+		assert(pkg1.Direct == (pkg2 != nil && pkg2.Complete()))
+	}
+
+	if pkg1.Direct {
+		return
+	}
+	pkg1.Direct = true
+	target.Imports = append(target.Imports, pkg1)
+
+	f, err := openPackage(path)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+
+	r, end, err := findExportData(f)
+	if err != nil {
+		return
+	}
+
+	if base.Debug.Export != 0 {
+		fmt.Printf("importing %s (%s)\n", path, f.Name())
+	}
+
+	c, err := r.ReadByte()
+	if err != nil {
+		return
+	}
+
+	pos := r.Offset()
+
+	// Map export data section into memory as a single large
+	// string. This reduces heap fragmentation and allows returning
+	// individual substrings very efficiently.
+	var data string
+	data, err = base.MapFile(r.File(), pos, end-pos)
+	if err != nil {
+		return
+	}
+
+	switch c {
+	case 'u':
+		if !buildcfg.Experiment.Unified {
+			base.Fatalf("unexpected export data format")
+		}
+
+		// TODO(mdempsky): This seems a bit clunky.
+		data = strings.TrimSuffix(data, "\n$$\n")
+
+		pr := pkgbits.NewPkgDecoder(pkg1.Path, data)
+
+		// Read package descriptors for both types2 and compiler backend.
+		readPackage(newPkgReader(pr), pkg1, false)
+		pkg2 = importer.ReadPackage(env, packages, pr)
+
+	case 'i':
+		if buildcfg.Experiment.Unified {
+			base.Fatalf("unexpected export data format")
+		}
+
+		typecheck.ReadImports(pkg1, data)
+
+		if packages != nil {
+			pkg2, err = importer.ImportData(packages, data, path)
+			if err != nil {
+				return
+			}
+		}
+
+	default:
+		// Indexed format is distinguished by an 'i' byte,
+		// whereas previous export formats started with 'c', 'd', or 'v'.
+		err = fmt.Errorf("unexpected package format byte: %v", c)
+		return
+	}
+
+	err = addFingerprint(path, f, end)
+	return
+}
+
+// findExportData returns a *bio.Reader positioned at the start of the
+// binary export data section, and a file offset for where to stop
+// reading.
+func findExportData(f *os.File) (r *bio.Reader, end int64, err error) {
+	r = bio.NewReader(f)
+
+	// check object header
+	line, err := r.ReadString('\n')
+	if err != nil {
+		return
+	}
+
+	if line == "!<arch>\n" { // package archive
+		// package export block should be first
+		sz := int64(archive.ReadHeader(r.Reader, "__.PKGDEF"))
+		if sz <= 0 {
+			err = errors.New("not a package file")
+			return
+		}
+		end = r.Offset() + sz
+		line, err = r.ReadString('\n')
+		if err != nil {
+			return
+		}
+	} else {
+		// Not an archive; provide end of file instead.
+		// TODO(mdempsky): I don't think this happens anymore.
+		var fi os.FileInfo
+		fi, err = f.Stat()
+		if err != nil {
+			return
+		}
+		end = fi.Size()
+	}
+
+	if !strings.HasPrefix(line, "go object ") {
+		err = fmt.Errorf("not a go object file: %s", line)
+		return
+	}
+	if expect := objabi.HeaderString(); line != expect {
+		err = fmt.Errorf("object is [%s] expected [%s]", line, expect)
+		return
+	}
+
+	// process header lines
+	for !strings.HasPrefix(line, "$$") {
+		line, err = r.ReadString('\n')
+		if err != nil {
+			return
+		}
+	}
+
+	// Expect $$B\n to signal binary import format.
+	if line != "$$B\n" {
+		err = errors.New("old export format no longer supported (recompile library)")
+		return
+	}
+
+	return
+}
+
+// addFingerprint reads the linker fingerprint included at the end of
+// the exportdata.
+func addFingerprint(path string, f *os.File, end int64) error {
+	const eom = "\n$$\n"
+	var fingerprint goobj.FingerprintType
+
+	var buf [len(fingerprint) + len(eom)]byte
+	if _, err := f.ReadAt(buf[:], end-int64(len(buf))); err != nil {
+		return err
+	}
+
+	// Caller should have given us the end position of the export data,
+	// which should end with the "\n$$\n" marker. As a consistency check
+	// to make sure we're reading at the right offset, make sure we
+	// found the marker.
+	if s := string(buf[len(fingerprint):]); s != eom {
+		return fmt.Errorf("expected $$ marker, but found %q", s)
+	}
+
+	copy(fingerprint[:], buf[:])
+	base.Ctxt.AddImport(path, fingerprint)
+
+	return nil
+}
+
+func checkImportPath(path string, allowSpace bool) error {
+	if path == "" {
+		return errors.New("import path is empty")
+	}
+
+	if strings.Contains(path, "\x00") {
+		return errors.New("import path contains NUL")
+	}
+
+	for ri := range base.ReservedImports {
+		if path == ri {
+			return fmt.Errorf("import path %q is reserved and cannot be used", path)
+		}
+	}
+
+	for _, r := range path {
+		switch {
+		case r == utf8.RuneError:
+			return fmt.Errorf("import path contains invalid UTF-8 sequence: %q", path)
+		case r < 0x20 || r == 0x7f:
+			return fmt.Errorf("import path contains control character: %q", path)
+		case r == '\\':
+			return fmt.Errorf("import path contains backslash; use slash: %q", path)
+		case !allowSpace && unicode.IsSpace(r):
+			return fmt.Errorf("import path contains space character: %q", path)
+		case strings.ContainsRune("!\"#$%&'()*,:;<=>?[]^`{|}", r):
+			return fmt.Errorf("import path contains invalid character '%c': %q", r, path)
+		}
+	}
+
+	return nil
+}
diff --git a/src/cmd/compile/internal/noder/irgen.go b/src/cmd/compile/internal/noder/irgen.go
new file mode 100644
index 0000000..d034926
--- /dev/null
+++ b/src/cmd/compile/internal/noder/irgen.go
@@ -0,0 +1,516 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+	"regexp"
+	"sort"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/dwarfgen"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+	"cmd/internal/src"
+)
+
+var versionErrorRx = regexp.MustCompile(`requires go[0-9]+\.[0-9]+ or later`)
+
+// checkFiles configures and runs the types2 checker on the given
+// parsed source files and then returns the result.
+func checkFiles(noders []*noder) (posMap, *types2.Package, *types2.Info) {
+	if base.SyntaxErrors() != 0 {
+		base.ErrorExit()
+	}
+
+	// setup and syntax error reporting
+	var m posMap
+	files := make([]*syntax.File, len(noders))
+	for i, p := range noders {
+		m.join(&p.posMap)
+		files[i] = p.file
+	}
+
+	// typechecking
+	ctxt := types2.NewContext()
+	importer := gcimports{
+		ctxt:     ctxt,
+		packages: make(map[string]*types2.Package),
+	}
+	conf := types2.Config{
+		Context:            ctxt,
+		GoVersion:          base.Flag.Lang,
+		IgnoreBranchErrors: true, // parser already checked via syntax.CheckBranches mode
+		Error: func(err error) {
+			terr := err.(types2.Error)
+			msg := terr.Msg
+			// if we have a version error, hint at the -lang setting
+			if versionErrorRx.MatchString(msg) {
+				msg = fmt.Sprintf("%s (-lang was set to %s; check go.mod)", msg, base.Flag.Lang)
+			}
+			base.ErrorfAt(m.makeXPos(terr.Pos), "%s", msg)
+		},
+		Importer:               &importer,
+		Sizes:                  &gcSizes{},
+		OldComparableSemantics: base.Flag.OldComparable, // default is new comparable semantics
+	}
+	info := &types2.Info{
+		StoreTypesInSyntax: true,
+		Defs:               make(map[*syntax.Name]types2.Object),
+		Uses:               make(map[*syntax.Name]types2.Object),
+		Selections:         make(map[*syntax.SelectorExpr]*types2.Selection),
+		Implicits:          make(map[syntax.Node]types2.Object),
+		Scopes:             make(map[syntax.Node]*types2.Scope),
+		Instances:          make(map[*syntax.Name]types2.Instance),
+		// expand as needed
+	}
+
+	pkg, err := conf.Check(base.Ctxt.Pkgpath, files, info)
+
+	// Check for anonymous interface cycles (#56103).
+	if base.Debug.InterfaceCycles == 0 {
+		var f cycleFinder
+		for _, file := range files {
+			syntax.Inspect(file, func(n syntax.Node) bool {
+				if n, ok := n.(*syntax.InterfaceType); ok {
+					if f.hasCycle(n.GetTypeInfo().Type.(*types2.Interface)) {
+						base.ErrorfAt(m.makeXPos(n.Pos()), "invalid recursive type: anonymous interface refers to itself (see https://go.dev/issue/56103)")
+
+						for typ := range f.cyclic {
+							f.cyclic[typ] = false // suppress duplicate errors
+						}
+					}
+					return false
+				}
+				return true
+			})
+		}
+	}
+
+	// Implementation restriction: we don't allow not-in-heap types to
+	// be used as type arguments (#54765).
+	{
+		type nihTarg struct {
+			pos src.XPos
+			typ types2.Type
+		}
+		var nihTargs []nihTarg
+
+		for name, inst := range info.Instances {
+			for i := 0; i < inst.TypeArgs.Len(); i++ {
+				if targ := inst.TypeArgs.At(i); isNotInHeap(targ) {
+					nihTargs = append(nihTargs, nihTarg{m.makeXPos(name.Pos()), targ})
+				}
+			}
+		}
+		sort.Slice(nihTargs, func(i, j int) bool {
+			ti, tj := nihTargs[i], nihTargs[j]
+			return ti.pos.Before(tj.pos)
+		})
+		for _, targ := range nihTargs {
+			base.ErrorfAt(targ.pos, "cannot use incomplete (or unallocatable) type as a type argument: %v", targ.typ)
+		}
+	}
+
+	base.ExitIfErrors()
+	if err != nil {
+		base.FatalfAt(src.NoXPos, "conf.Check error: %v", err)
+	}
+
+	return m, pkg, info
+}
+
+// check2 type checks a Go package using types2, and then generates IR
+// using the results.
+func check2(noders []*noder) {
+	m, pkg, info := checkFiles(noders)
+
+	g := irgen{
+		target: typecheck.Target,
+		self:   pkg,
+		info:   info,
+		posMap: m,
+		objs:   make(map[types2.Object]*ir.Name),
+		typs:   make(map[types2.Type]*types.Type),
+	}
+	g.generate(noders)
+}
+
+// Information about sub-dictionary entries in a dictionary
+type subDictInfo struct {
+	// Call or XDOT node that requires a dictionary.
+	callNode ir.Node
+	// Saved CallExpr.X node (*ir.SelectorExpr or *InstExpr node) for a generic
+	// method or function call, since this node will get dropped when the generic
+	// method/function call is transformed to a call on the instantiated shape
+	// function. Nil for other kinds of calls or XDOTs.
+	savedXNode ir.Node
+}
+
+// dictInfo is the dictionary format for an instantiation of a generic function with
+// particular shapes. shapeParams, derivedTypes, subDictCalls, itabConvs, and methodExprClosures
+// describe the actual dictionary entries in order, and the remaining fields are other info
+// needed in doing dictionary processing during compilation.
+type dictInfo struct {
+	// Types substituted for the type parameters, which are shape types.
+	shapeParams []*types.Type
+	// All types derived from those typeparams used in the instantiation.
+	derivedTypes []*types.Type
+	// Nodes in the instantiation that requires a subdictionary. Includes
+	// method and function calls (OCALL), function values (OFUNCINST), method
+	// values/expressions (OXDOT).
+	subDictCalls []subDictInfo
+	// Nodes in the instantiation that are a conversion from a typeparam/derived
+	// type to a specific interface.
+	itabConvs []ir.Node
+	// Method expression closures. For a generic type T with method M(arg1, arg2) res,
+	// these closures are func(rcvr T, arg1, arg2) res.
+	// These closures capture no variables, they are just the generic version of ·f symbols
+	// that live in the dictionary instead of in the readonly globals section.
+	methodExprClosures []methodExprClosure
+
+	// Mapping from each shape type that substitutes a type param, to its
+	// type bound (which is also substituted with shapes if it is parameterized)
+	shapeToBound map[*types.Type]*types.Type
+
+	// For type switches on nonempty interfaces, a map from OTYPE entries of
+	// HasShape type, to the interface type we're switching from.
+	type2switchType map[ir.Node]*types.Type
+
+	startSubDict            int // Start of dict entries for subdictionaries
+	startItabConv           int // Start of dict entries for itab conversions
+	startMethodExprClosures int // Start of dict entries for closures for method expressions
+	dictLen                 int // Total number of entries in dictionary
+}
+
+type methodExprClosure struct {
+	idx  int    // index in list of shape parameters
+	name string // method name
+}
+
+// instInfo is information gathered on an shape instantiation of a function.
+type instInfo struct {
+	fun       *ir.Func // The instantiated function (with body)
+	dictParam *ir.Name // The node inside fun that refers to the dictionary param
+
+	dictInfo *dictInfo
+}
+
+type irgen struct {
+	target *ir.Package
+	self   *types2.Package
+	info   *types2.Info
+
+	posMap
+	objs   map[types2.Object]*ir.Name
+	typs   map[types2.Type]*types.Type
+	marker dwarfgen.ScopeMarker
+
+	// laterFuncs records tasks that need to run after all declarations
+	// are processed.
+	laterFuncs []func()
+	// haveEmbed indicates whether the current node belongs to file that
+	// imports "embed" package.
+	haveEmbed bool
+
+	// exprStmtOK indicates whether it's safe to generate expressions or
+	// statements yet.
+	exprStmtOK bool
+
+	// types which we need to finish, by doing g.fillinMethods.
+	typesToFinalize []*typeDelayInfo
+
+	// True when we are compiling a top-level generic function or method. Use to
+	// avoid adding closures of generic functions/methods to the target.Decls
+	// list.
+	topFuncIsGeneric bool
+
+	// The context during type/function/method declarations that is used to
+	// uniquely name type parameters. We need unique names for type params so we
+	// can be sure they match up correctly between types2-to-types1 translation
+	// and types1 importing.
+	curDecl string
+}
+
+// genInst has the information for creating needed instantiations and modifying
+// functions to use instantiations.
+type genInst struct {
+	dnum int // for generating unique dictionary variables
+
+	// Map from the names of all instantiations to information about the
+	// instantiations.
+	instInfoMap map[*types.Sym]*instInfo
+
+	// Dictionary syms which we need to finish, by writing out any itabconv
+	// or method expression closure entries.
+	dictSymsToFinalize []*delayInfo
+
+	// New instantiations created during this round of buildInstantiations().
+	newInsts []ir.Node
+}
+
+func (g *irgen) later(fn func()) {
+	g.laterFuncs = append(g.laterFuncs, fn)
+}
+
+type delayInfo struct {
+	gf     *ir.Name
+	targs  []*types.Type
+	sym    *types.Sym
+	off    int
+	isMeth bool
+}
+
+type typeDelayInfo struct {
+	typ  *types2.Named
+	ntyp *types.Type
+}
+
+func (g *irgen) generate(noders []*noder) {
+	types.LocalPkg.Name = g.self.Name()
+	typecheck.TypecheckAllowed = true
+
+	// Prevent size calculations until we set the underlying type
+	// for all package-block defined types.
+	types.DeferCheckSize()
+
+	// At this point, types2 has already handled name resolution and
+	// type checking. We just need to map from its object and type
+	// representations to those currently used by the rest of the
+	// compiler. This happens in a few passes.
+
+	// 1. Process all import declarations. We use the compiler's own
+	// importer for this, rather than types2's gcimporter-derived one,
+	// to handle extensions and inline function bodies correctly.
+	//
+	// Also, we need to do this in a separate pass, because mappings are
+	// instantiated on demand. If we interleaved processing import
+	// declarations with other declarations, it's likely we'd end up
+	// wanting to map an object/type from another source file, but not
+	// yet have the import data it relies on.
+	declLists := make([][]syntax.Decl, len(noders))
+Outer:
+	for i, p := range noders {
+		g.pragmaFlags(p.file.Pragma, ir.GoBuildPragma)
+		for j, decl := range p.file.DeclList {
+			switch decl := decl.(type) {
+			case *syntax.ImportDecl:
+				g.importDecl(p, decl)
+			default:
+				declLists[i] = p.file.DeclList[j:]
+				continue Outer // no more ImportDecls
+			}
+		}
+	}
+
+	// 2. Process all package-block type declarations. As with imports,
+	// we need to make sure all types are properly instantiated before
+	// trying to map any expressions that utilize them. In particular,
+	// we need to make sure type pragmas are already known (see comment
+	// in irgen.typeDecl).
+	//
+	// We could perhaps instead defer processing of package-block
+	// variable initializers and function bodies, like noder does, but
+	// special-casing just package-block type declarations minimizes the
+	// differences between processing package-block and function-scoped
+	// declarations.
+	for _, declList := range declLists {
+		for _, decl := range declList {
+			switch decl := decl.(type) {
+			case *syntax.TypeDecl:
+				g.typeDecl((*ir.Nodes)(&g.target.Decls), decl)
+			}
+		}
+	}
+	types.ResumeCheckSize()
+
+	// 3. Process all remaining declarations.
+	for i, declList := range declLists {
+		old := g.haveEmbed
+		g.haveEmbed = noders[i].importedEmbed
+		g.decls((*ir.Nodes)(&g.target.Decls), declList)
+		g.haveEmbed = old
+	}
+	g.exprStmtOK = true
+
+	// 4. Run any "later" tasks. Avoid using 'range' so that tasks can
+	// recursively queue further tasks. (Not currently utilized though.)
+	for len(g.laterFuncs) > 0 {
+		fn := g.laterFuncs[0]
+		g.laterFuncs = g.laterFuncs[1:]
+		fn()
+	}
+
+	if base.Flag.W > 1 {
+		for _, n := range g.target.Decls {
+			s := fmt.Sprintf("\nafter noder2 %v", n)
+			ir.Dump(s, n)
+		}
+	}
+
+	for _, p := range noders {
+		// Process linkname and cgo pragmas.
+		p.processPragmas()
+
+		// Double check for any type-checking inconsistencies. This can be
+		// removed once we're confident in IR generation results.
+		syntax.Crawl(p.file, func(n syntax.Node) bool {
+			g.validate(n)
+			return false
+		})
+	}
+
+	if base.Flag.Complete {
+		for _, n := range g.target.Decls {
+			if fn, ok := n.(*ir.Func); ok {
+				if fn.Body == nil && fn.Nname.Sym().Linkname == "" {
+					base.ErrorfAt(fn.Pos(), "missing function body")
+				}
+			}
+		}
+	}
+
+	// Check for unusual case where noder2 encounters a type error that types2
+	// doesn't check for (e.g. notinheap incompatibility).
+	base.ExitIfErrors()
+
+	typecheck.DeclareUniverse()
+
+	// Create any needed instantiations of generic functions and transform
+	// existing and new functions to use those instantiations.
+	BuildInstantiations()
+
+	// Remove all generic functions from g.target.Decl, since they have been
+	// used for stenciling, but don't compile. Generic functions will already
+	// have been marked for export as appropriate.
+	j := 0
+	for i, decl := range g.target.Decls {
+		if decl.Op() != ir.ODCLFUNC || !decl.Type().HasTParam() {
+			g.target.Decls[j] = g.target.Decls[i]
+			j++
+		}
+	}
+	g.target.Decls = g.target.Decls[:j]
+
+	base.Assertf(len(g.laterFuncs) == 0, "still have %d later funcs", len(g.laterFuncs))
+}
+
+func (g *irgen) unhandled(what string, p poser) {
+	base.FatalfAt(g.pos(p), "unhandled %s: %T", what, p)
+	panic("unreachable")
+}
+
+// delayTransform returns true if we should delay all transforms, because we are
+// creating the nodes for a generic function/method.
+func (g *irgen) delayTransform() bool {
+	return g.topFuncIsGeneric
+}
+
+func (g *irgen) typeAndValue(x syntax.Expr) syntax.TypeAndValue {
+	tv := x.GetTypeInfo()
+	if tv.Type == nil {
+		base.FatalfAt(g.pos(x), "missing type for %v (%T)", x, x)
+	}
+	return tv
+}
+
+func (g *irgen) type2(x syntax.Expr) syntax.Type {
+	tv := x.GetTypeInfo()
+	if tv.Type == nil {
+		base.FatalfAt(g.pos(x), "missing type for %v (%T)", x, x)
+	}
+	return tv.Type
+}
+
+// A cycleFinder detects anonymous interface cycles (go.dev/issue/56103).
+type cycleFinder struct {
+	cyclic map[*types2.Interface]bool
+}
+
+// hasCycle reports whether typ is part of an anonymous interface cycle.
+func (f *cycleFinder) hasCycle(typ *types2.Interface) bool {
+	// We use Method instead of ExplicitMethod to implicitly expand any
+	// embedded interfaces. Then we just need to walk any anonymous
+	// types, keeping track of *types2.Interface types we visit along
+	// the way.
+	for i := 0; i < typ.NumMethods(); i++ {
+		if f.visit(typ.Method(i).Type()) {
+			return true
+		}
+	}
+	return false
+}
+
+// visit recursively walks typ0 to check any referenced interface types.
+func (f *cycleFinder) visit(typ0 types2.Type) bool {
+	for { // loop for tail recursion
+		switch typ := typ0.(type) {
+		default:
+			base.Fatalf("unexpected type: %T", typ)
+
+		case *types2.Basic, *types2.Named, *types2.TypeParam:
+			return false // named types cannot be part of an anonymous cycle
+		case *types2.Pointer:
+			typ0 = typ.Elem()
+		case *types2.Array:
+			typ0 = typ.Elem()
+		case *types2.Chan:
+			typ0 = typ.Elem()
+		case *types2.Map:
+			if f.visit(typ.Key()) {
+				return true
+			}
+			typ0 = typ.Elem()
+		case *types2.Slice:
+			typ0 = typ.Elem()
+
+		case *types2.Struct:
+			for i := 0; i < typ.NumFields(); i++ {
+				if f.visit(typ.Field(i).Type()) {
+					return true
+				}
+			}
+			return false
+
+		case *types2.Interface:
+			// The empty interface (e.g., "any") cannot be part of a cycle.
+			if typ.NumExplicitMethods() == 0 && typ.NumEmbeddeds() == 0 {
+				return false
+			}
+
+			// As an optimization, we wait to allocate cyclic here, after
+			// we've found at least one other (non-empty) anonymous
+			// interface. This means when a cycle is present, we need to
+			// make an extra recursive call to actually detect it. But for
+			// most packages, it allows skipping the map allocation
+			// entirely.
+			if x, ok := f.cyclic[typ]; ok {
+				return x
+			}
+			if f.cyclic == nil {
+				f.cyclic = make(map[*types2.Interface]bool)
+			}
+			f.cyclic[typ] = true
+			if f.hasCycle(typ) {
+				return true
+			}
+			f.cyclic[typ] = false
+			return false
+
+		case *types2.Signature:
+			return f.visit(typ.Params()) || f.visit(typ.Results())
+		case *types2.Tuple:
+			for i := 0; i < typ.Len(); i++ {
+				if f.visit(typ.At(i).Type()) {
+					return true
+				}
+			}
+			return false
+		}
+	}
+}
diff --git a/src/cmd/compile/internal/noder/lex.go b/src/cmd/compile/internal/noder/lex.go
new file mode 100644
index 0000000..c964eca
--- /dev/null
+++ b/src/cmd/compile/internal/noder/lex.go
@@ -0,0 +1,184 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+	"internal/buildcfg"
+	"strings"
+
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+)
+
+func isSpace(c rune) bool {
+	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
+}
+
+func isQuoted(s string) bool {
+	return len(s) >= 2 && s[0] == '"' && s[len(s)-1] == '"'
+}
+
+const (
+	funcPragmas = ir.Nointerface |
+		ir.Noescape |
+		ir.Norace |
+		ir.Nosplit |
+		ir.Noinline |
+		ir.NoCheckPtr |
+		ir.RegisterParams | // TODO(register args) remove after register abi is working
+		ir.CgoUnsafeArgs |
+		ir.UintptrKeepAlive |
+		ir.UintptrEscapes |
+		ir.Systemstack |
+		ir.Nowritebarrier |
+		ir.Nowritebarrierrec |
+		ir.Yeswritebarrierrec
+)
+
+func pragmaFlag(verb string) ir.PragmaFlag {
+	switch verb {
+	case "go:build":
+		return ir.GoBuildPragma
+	case "go:nointerface":
+		if buildcfg.Experiment.FieldTrack {
+			return ir.Nointerface
+		}
+	case "go:noescape":
+		return ir.Noescape
+	case "go:norace":
+		return ir.Norace
+	case "go:nosplit":
+		return ir.Nosplit | ir.NoCheckPtr // implies NoCheckPtr (see #34972)
+	case "go:noinline":
+		return ir.Noinline
+	case "go:nocheckptr":
+		return ir.NoCheckPtr
+	case "go:systemstack":
+		return ir.Systemstack
+	case "go:nowritebarrier":
+		return ir.Nowritebarrier
+	case "go:nowritebarrierrec":
+		return ir.Nowritebarrierrec | ir.Nowritebarrier // implies Nowritebarrier
+	case "go:yeswritebarrierrec":
+		return ir.Yeswritebarrierrec
+	case "go:cgo_unsafe_args":
+		return ir.CgoUnsafeArgs | ir.NoCheckPtr // implies NoCheckPtr (see #34968)
+	case "go:uintptrkeepalive":
+		return ir.UintptrKeepAlive
+	case "go:uintptrescapes":
+		// This directive extends //go:uintptrkeepalive by forcing
+		// uintptr arguments to escape to the heap, which makes stack
+		// growth safe.
+		return ir.UintptrEscapes | ir.UintptrKeepAlive // implies UintptrKeepAlive
+	case "go:registerparams": // TODO(register args) remove after register abi is working
+		return ir.RegisterParams
+	}
+	return 0
+}
+
+// pragcgo is called concurrently if files are parsed concurrently.
+func (p *noder) pragcgo(pos syntax.Pos, text string) {
+	f := pragmaFields(text)
+
+	verb := strings.TrimPrefix(f[0], "go:")
+	f[0] = verb
+
+	switch verb {
+	case "cgo_export_static", "cgo_export_dynamic":
+		switch {
+		case len(f) == 2 && !isQuoted(f[1]):
+		case len(f) == 3 && !isQuoted(f[1]) && !isQuoted(f[2]):
+		default:
+			p.error(syntax.Error{Pos: pos, Msg: fmt.Sprintf(`usage: //go:%s local [remote]`, verb)})
+			return
+		}
+	case "cgo_import_dynamic":
+		switch {
+		case len(f) == 2 && !isQuoted(f[1]):
+		case len(f) == 3 && !isQuoted(f[1]) && !isQuoted(f[2]):
+		case len(f) == 4 && !isQuoted(f[1]) && !isQuoted(f[2]) && isQuoted(f[3]):
+			f[3] = strings.Trim(f[3], `"`)
+			if buildcfg.GOOS == "aix" && f[3] != "" {
+				// On Aix, library pattern must be "lib.a/object.o"
+				// or "lib.a/libname.so.X"
+				n := strings.Split(f[3], "/")
+				if len(n) != 2 || !strings.HasSuffix(n[0], ".a") || (!strings.HasSuffix(n[1], ".o") && !strings.Contains(n[1], ".so.")) {
+					p.error(syntax.Error{Pos: pos, Msg: `usage: //go:cgo_import_dynamic local [remote ["lib.a/object.o"]]`})
+					return
+				}
+			}
+		default:
+			p.error(syntax.Error{Pos: pos, Msg: `usage: //go:cgo_import_dynamic local [remote ["library"]]`})
+			return
+		}
+	case "cgo_import_static":
+		switch {
+		case len(f) == 2 && !isQuoted(f[1]):
+		default:
+			p.error(syntax.Error{Pos: pos, Msg: `usage: //go:cgo_import_static local`})
+			return
+		}
+	case "cgo_dynamic_linker":
+		switch {
+		case len(f) == 2 && isQuoted(f[1]):
+			f[1] = strings.Trim(f[1], `"`)
+		default:
+			p.error(syntax.Error{Pos: pos, Msg: `usage: //go:cgo_dynamic_linker "path"`})
+			return
+		}
+	case "cgo_ldflag":
+		switch {
+		case len(f) == 2 && isQuoted(f[1]):
+			f[1] = strings.Trim(f[1], `"`)
+		default:
+			p.error(syntax.Error{Pos: pos, Msg: `usage: //go:cgo_ldflag "arg"`})
+			return
+		}
+	default:
+		return
+	}
+	p.pragcgobuf = append(p.pragcgobuf, f)
+}
+
+// pragmaFields is similar to strings.FieldsFunc(s, isSpace)
+// but does not split when inside double quoted regions and always
+// splits before the start and after the end of a double quoted region.
+// pragmaFields does not recognize escaped quotes. If a quote in s is not
+// closed the part after the opening quote will not be returned as a field.
+func pragmaFields(s string) []string {
+	var a []string
+	inQuote := false
+	fieldStart := -1 // Set to -1 when looking for start of field.
+	for i, c := range s {
+		switch {
+		case c == '"':
+			if inQuote {
+				inQuote = false
+				a = append(a, s[fieldStart:i+1])
+				fieldStart = -1
+			} else {
+				inQuote = true
+				if fieldStart >= 0 {
+					a = append(a, s[fieldStart:i])
+				}
+				fieldStart = i
+			}
+		case !inQuote && isSpace(c):
+			if fieldStart >= 0 {
+				a = append(a, s[fieldStart:i])
+				fieldStart = -1
+			}
+		default:
+			if fieldStart == -1 {
+				fieldStart = i
+			}
+		}
+	}
+	if !inQuote && fieldStart >= 0 { // Last field might end at the end of the string.
+		a = append(a, s[fieldStart:])
+	}
+	return a
+}
diff --git a/src/cmd/compile/internal/noder/lex_test.go b/src/cmd/compile/internal/noder/lex_test.go
new file mode 100644
index 0000000..85a3f06
--- /dev/null
+++ b/src/cmd/compile/internal/noder/lex_test.go
@@ -0,0 +1,122 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"reflect"
+	"runtime"
+	"testing"
+
+	"cmd/compile/internal/syntax"
+)
+
+func eq(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := 0; i < len(a); i++ {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func TestPragmaFields(t *testing.T) {
+	var tests = []struct {
+		in   string
+		want []string
+	}{
+		{"", []string{}},
+		{" \t ", []string{}},
+		{`""""`, []string{`""`, `""`}},
+		{"  a'b'c  ", []string{"a'b'c"}},
+		{"1 2 3 4", []string{"1", "2", "3", "4"}},
+		{"\n☺\t☹\n", []string{"☺", "☹"}},
+		{`"1 2 "  3  " 4 5"`, []string{`"1 2 "`, `3`, `" 4 5"`}},
+		{`"1""2 3""4"`, []string{`"1"`, `"2 3"`, `"4"`}},
+		{`12"34"`, []string{`12`, `"34"`}},
+		{`12"34 `, []string{`12`}},
+	}
+
+	for _, tt := range tests {
+		got := pragmaFields(tt.in)
+		if !eq(got, tt.want) {
+			t.Errorf("pragmaFields(%q) = %v; want %v", tt.in, got, tt.want)
+			continue
+		}
+	}
+}
+
+func TestPragcgo(t *testing.T) {
+	type testStruct struct {
+		in   string
+		want []string
+	}
+
+	var tests = []testStruct{
+		{`go:cgo_export_dynamic local`, []string{`cgo_export_dynamic`, `local`}},
+		{`go:cgo_export_dynamic local remote`, []string{`cgo_export_dynamic`, `local`, `remote`}},
+		{`go:cgo_export_dynamic local' remote'`, []string{`cgo_export_dynamic`, `local'`, `remote'`}},
+		{`go:cgo_export_static local`, []string{`cgo_export_static`, `local`}},
+		{`go:cgo_export_static local remote`, []string{`cgo_export_static`, `local`, `remote`}},
+		{`go:cgo_export_static local' remote'`, []string{`cgo_export_static`, `local'`, `remote'`}},
+		{`go:cgo_import_dynamic local`, []string{`cgo_import_dynamic`, `local`}},
+		{`go:cgo_import_dynamic local remote`, []string{`cgo_import_dynamic`, `local`, `remote`}},
+		{`go:cgo_import_static local`, []string{`cgo_import_static`, `local`}},
+		{`go:cgo_import_static local'`, []string{`cgo_import_static`, `local'`}},
+		{`go:cgo_dynamic_linker "/path/"`, []string{`cgo_dynamic_linker`, `/path/`}},
+		{`go:cgo_dynamic_linker "/p ath/"`, []string{`cgo_dynamic_linker`, `/p ath/`}},
+		{`go:cgo_ldflag "arg"`, []string{`cgo_ldflag`, `arg`}},
+		{`go:cgo_ldflag "a rg"`, []string{`cgo_ldflag`, `a rg`}},
+	}
+
+	if runtime.GOOS != "aix" {
+		tests = append(tests, []testStruct{
+			{`go:cgo_import_dynamic local remote "library"`, []string{`cgo_import_dynamic`, `local`, `remote`, `library`}},
+			{`go:cgo_import_dynamic local' remote' "lib rary"`, []string{`cgo_import_dynamic`, `local'`, `remote'`, `lib rary`}},
+		}...)
+	} else {
+		// cgo_import_dynamic with a library is slightly different on AIX
+		// as the library field must follow the pattern [libc.a/object.o].
+		tests = append(tests, []testStruct{
+			{`go:cgo_import_dynamic local remote "lib.a/obj.o"`, []string{`cgo_import_dynamic`, `local`, `remote`, `lib.a/obj.o`}},
+			// This test must fail.
+			{`go:cgo_import_dynamic local' remote' "library"`, []string{`<unknown position>: usage: //go:cgo_import_dynamic local [remote ["lib.a/object.o"]]`}},
+		}...)
+
+	}
+
+	var p noder
+	var nopos syntax.Pos
+	for _, tt := range tests {
+
+		p.err = make(chan syntax.Error)
+		gotch := make(chan [][]string, 1)
+		go func() {
+			p.pragcgobuf = nil
+			p.pragcgo(nopos, tt.in)
+			if p.pragcgobuf != nil {
+				gotch <- p.pragcgobuf
+			}
+		}()
+
+		select {
+		case e := <-p.err:
+			want := tt.want[0]
+			if e.Error() != want {
+				t.Errorf("pragcgo(%q) = %q; want %q", tt.in, e, want)
+				continue
+			}
+		case got := <-gotch:
+			want := [][]string{tt.want}
+			if !reflect.DeepEqual(got, want) {
+				t.Errorf("pragcgo(%q) = %q; want %q", tt.in, got, want)
+				continue
+			}
+		}
+
+	}
+}
diff --git a/src/cmd/compile/internal/noder/linker.go b/src/cmd/compile/internal/noder/linker.go
new file mode 100644
index 0000000..5d0459d
--- /dev/null
+++ b/src/cmd/compile/internal/noder/linker.go
@@ -0,0 +1,337 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"internal/pkgbits"
+	"io"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/reflectdata"
+	"cmd/compile/internal/types"
+	"cmd/internal/goobj"
+	"cmd/internal/obj"
+)
+
+// This file implements the unified IR linker, which combines the
+// local package's stub data with imported package data to produce a
+// complete export data file. It also rewrites the compiler's
+// extension data sections based on the results of compilation (e.g.,
+// the function inlining cost and linker symbol index assignments).
+//
+// TODO(mdempsky): Using the name "linker" here is confusing, because
+// readers are likely to mistake references to it for cmd/link. But
+// there's a shortage of good names for "something that combines
+// multiple parts into a cohesive whole"... e.g., "assembler" and
+// "compiler" are also already taken.
+
+// TODO(mdempsky): Should linker go into pkgbits? Probably the
+// low-level linking details can be moved there, but the logic for
+// handling extension data needs to stay in the compiler.
+
+// A linker combines a package's stub export data with any referenced
+// elements from imported packages into a single, self-contained
+// export data file.
+type linker struct {
+	pw pkgbits.PkgEncoder
+
+	pkgs   map[string]pkgbits.Index
+	decls  map[*types.Sym]pkgbits.Index
+	bodies map[*types.Sym]pkgbits.Index
+}
+
+// relocAll ensures that all elements specified by pr and relocs are
+// copied into the output export data file, and returns the
+// corresponding indices in the output.
+func (l *linker) relocAll(pr *pkgReader, relocs []pkgbits.RelocEnt) []pkgbits.RelocEnt {
+	res := make([]pkgbits.RelocEnt, len(relocs))
+	for i, rent := range relocs {
+		rent.Idx = l.relocIdx(pr, rent.Kind, rent.Idx)
+		res[i] = rent
+	}
+	return res
+}
+
+// relocIdx ensures a single element is copied into the output export
+// data file, and returns the corresponding index in the output.
+func (l *linker) relocIdx(pr *pkgReader, k pkgbits.RelocKind, idx pkgbits.Index) pkgbits.Index {
+	assert(pr != nil)
+
+	absIdx := pr.AbsIdx(k, idx)
+
+	if newidx := pr.newindex[absIdx]; newidx != 0 {
+		return ^newidx
+	}
+
+	var newidx pkgbits.Index
+	switch k {
+	case pkgbits.RelocString:
+		newidx = l.relocString(pr, idx)
+	case pkgbits.RelocPkg:
+		newidx = l.relocPkg(pr, idx)
+	case pkgbits.RelocObj:
+		newidx = l.relocObj(pr, idx)
+
+	default:
+		// Generic relocations.
+		//
+		// TODO(mdempsky): Deduplicate more sections? In fact, I think
+		// every section could be deduplicated. This would also be easier
+		// if we do external relocations.
+
+		w := l.pw.NewEncoderRaw(k)
+		l.relocCommon(pr, &w, k, idx)
+		newidx = w.Idx
+	}
+
+	pr.newindex[absIdx] = ^newidx
+
+	return newidx
+}
+
+// relocString copies the specified string from pr into the output
+// export data file, deduplicating it against other strings.
+func (l *linker) relocString(pr *pkgReader, idx pkgbits.Index) pkgbits.Index {
+	return l.pw.StringIdx(pr.StringIdx(idx))
+}
+
+// relocPkg copies the specified package from pr into the output
+// export data file, rewriting its import path to match how it was
+// imported.
+//
+// TODO(mdempsky): Since CL 391014, we already have the compilation
+// unit's import path, so there should be no need to rewrite packages
+// anymore.
+func (l *linker) relocPkg(pr *pkgReader, idx pkgbits.Index) pkgbits.Index {
+	path := pr.PeekPkgPath(idx)
+
+	if newidx, ok := l.pkgs[path]; ok {
+		return newidx
+	}
+
+	r := pr.NewDecoder(pkgbits.RelocPkg, idx, pkgbits.SyncPkgDef)
+	w := l.pw.NewEncoder(pkgbits.RelocPkg, pkgbits.SyncPkgDef)
+	l.pkgs[path] = w.Idx
+
+	// TODO(mdempsky): We end up leaving an empty string reference here
+	// from when the package was originally written as "". Probably not
+	// a big deal, but a little annoying. Maybe relocating
+	// cross-references in place is the way to go after all.
+	w.Relocs = l.relocAll(pr, r.Relocs)
+
+	_ = r.String() // original path
+	w.String(path)
+
+	io.Copy(&w.Data, &r.Data)
+
+	return w.Flush()
+}
+
+// relocObj copies the specified object from pr into the output export
+// data file, rewriting its compiler-private extension data (e.g.,
+// adding inlining cost and escape analysis results for functions).
+func (l *linker) relocObj(pr *pkgReader, idx pkgbits.Index) pkgbits.Index {
+	path, name, tag := pr.PeekObj(idx)
+	sym := types.NewPkg(path, "").Lookup(name)
+
+	if newidx, ok := l.decls[sym]; ok {
+		return newidx
+	}
+
+	if tag == pkgbits.ObjStub && path != "builtin" && path != "unsafe" {
+		pri, ok := objReader[sym]
+		if !ok {
+			base.Fatalf("missing reader for %q.%v", path, name)
+		}
+		assert(ok)
+
+		pr = pri.pr
+		idx = pri.idx
+
+		path2, name2, tag2 := pr.PeekObj(idx)
+		sym2 := types.NewPkg(path2, "").Lookup(name2)
+		assert(sym == sym2)
+		assert(tag2 != pkgbits.ObjStub)
+	}
+
+	w := l.pw.NewEncoderRaw(pkgbits.RelocObj)
+	wext := l.pw.NewEncoderRaw(pkgbits.RelocObjExt)
+	wname := l.pw.NewEncoderRaw(pkgbits.RelocName)
+	wdict := l.pw.NewEncoderRaw(pkgbits.RelocObjDict)
+
+	l.decls[sym] = w.Idx
+	assert(wext.Idx == w.Idx)
+	assert(wname.Idx == w.Idx)
+	assert(wdict.Idx == w.Idx)
+
+	l.relocCommon(pr, &w, pkgbits.RelocObj, idx)
+	l.relocCommon(pr, &wname, pkgbits.RelocName, idx)
+	l.relocCommon(pr, &wdict, pkgbits.RelocObjDict, idx)
+
+	// Generic types and functions won't have definitions, and imported
+	// objects may not either.
+	obj, _ := sym.Def.(*ir.Name)
+	local := sym.Pkg == types.LocalPkg
+
+	if local && obj != nil {
+		wext.Sync(pkgbits.SyncObject1)
+		switch tag {
+		case pkgbits.ObjFunc:
+			l.relocFuncExt(&wext, obj)
+		case pkgbits.ObjType:
+			l.relocTypeExt(&wext, obj)
+		case pkgbits.ObjVar:
+			l.relocVarExt(&wext, obj)
+		}
+		wext.Flush()
+	} else {
+		l.relocCommon(pr, &wext, pkgbits.RelocObjExt, idx)
+	}
+
+	// Check if we need to export the inline bodies for functions and
+	// methods.
+	if obj != nil {
+		if obj.Op() == ir.ONAME && obj.Class == ir.PFUNC {
+			l.exportBody(obj, local)
+		}
+
+		if obj.Op() == ir.OTYPE && !obj.Alias() {
+			if typ := obj.Type(); !typ.IsInterface() {
+				for _, method := range typ.Methods().Slice() {
+					l.exportBody(method.Nname.(*ir.Name), local)
+				}
+			}
+		}
+	}
+
+	return w.Idx
+}
+
+// exportBody exports the given function or method's body, if
+// appropriate. local indicates whether it's a local function or
+// method available on a locally declared type. (Due to cross-package
+// type aliases, a method may be imported, but still available on a
+// locally declared type.)
+func (l *linker) exportBody(obj *ir.Name, local bool) {
+	assert(obj.Op() == ir.ONAME && obj.Class == ir.PFUNC)
+
+	fn := obj.Func
+	if fn.Inl == nil {
+		return // not inlinable anyway
+	}
+
+	// As a simple heuristic, if the function was declared in this
+	// package or we inlined it somewhere in this package, then we'll
+	// (re)export the function body. This isn't perfect, but seems
+	// reasonable in practice. In particular, it has the nice property
+	// that in the worst case, adding a blank import ensures the
+	// function body is available for inlining.
+	//
+	// TODO(mdempsky): Reimplement the reachable method crawling logic
+	// from typecheck/crawler.go.
+	exportBody := local || fn.Inl.Body != nil
+	if !exportBody {
+		return
+	}
+
+	sym := obj.Sym()
+	if _, ok := l.bodies[sym]; ok {
+		// Due to type aliases, we might visit methods multiple times.
+		base.AssertfAt(obj.Type().Recv() != nil, obj.Pos(), "expected method: %v", obj)
+		return
+	}
+
+	pri, ok := bodyReaderFor(fn)
+	assert(ok)
+	l.bodies[sym] = l.relocIdx(pri.pr, pkgbits.RelocBody, pri.idx)
+}
+
+// relocCommon copies the specified element from pr into w,
+// recursively relocating any referenced elements as well.
+func (l *linker) relocCommon(pr *pkgReader, w *pkgbits.Encoder, k pkgbits.RelocKind, idx pkgbits.Index) {
+	r := pr.NewDecoderRaw(k, idx)
+	w.Relocs = l.relocAll(pr, r.Relocs)
+	io.Copy(&w.Data, &r.Data)
+	w.Flush()
+}
+
+func (l *linker) pragmaFlag(w *pkgbits.Encoder, pragma ir.PragmaFlag) {
+	w.Sync(pkgbits.SyncPragma)
+	w.Int(int(pragma))
+}
+
+func (l *linker) relocFuncExt(w *pkgbits.Encoder, name *ir.Name) {
+	w.Sync(pkgbits.SyncFuncExt)
+
+	l.pragmaFlag(w, name.Func.Pragma)
+	l.linkname(w, name)
+
+	// Relocated extension data.
+	w.Bool(true)
+
+	// Record definition ABI so cross-ABI calls can be direct.
+	// This is important for the performance of calling some
+	// common functions implemented in assembly (e.g., bytealg).
+	w.Uint64(uint64(name.Func.ABI))
+
+	// Escape analysis.
+	for _, fs := range &types.RecvsParams {
+		for _, f := range fs(name.Type()).FieldSlice() {
+			w.String(f.Note)
+		}
+	}
+
+	if inl := name.Func.Inl; w.Bool(inl != nil) {
+		w.Len(int(inl.Cost))
+		w.Bool(inl.CanDelayResults)
+	}
+
+	w.Sync(pkgbits.SyncEOF)
+}
+
+func (l *linker) relocTypeExt(w *pkgbits.Encoder, name *ir.Name) {
+	w.Sync(pkgbits.SyncTypeExt)
+
+	typ := name.Type()
+
+	l.pragmaFlag(w, name.Pragma())
+
+	// For type T, export the index of type descriptor symbols of T and *T.
+	l.lsymIdx(w, "", reflectdata.TypeLinksym(typ))
+	l.lsymIdx(w, "", reflectdata.TypeLinksym(typ.PtrTo()))
+
+	if typ.Kind() != types.TINTER {
+		for _, method := range typ.Methods().Slice() {
+			l.relocFuncExt(w, method.Nname.(*ir.Name))
+		}
+	}
+}
+
+func (l *linker) relocVarExt(w *pkgbits.Encoder, name *ir.Name) {
+	w.Sync(pkgbits.SyncVarExt)
+	l.linkname(w, name)
+}
+
+func (l *linker) linkname(w *pkgbits.Encoder, name *ir.Name) {
+	w.Sync(pkgbits.SyncLinkname)
+
+	linkname := name.Sym().Linkname
+	if !l.lsymIdx(w, linkname, name.Linksym()) {
+		w.String(linkname)
+	}
+}
+
+func (l *linker) lsymIdx(w *pkgbits.Encoder, linkname string, lsym *obj.LSym) bool {
+	if lsym.PkgIdx > goobj.PkgIdxSelf || (lsym.PkgIdx == goobj.PkgIdxInvalid && !lsym.Indexed()) || linkname != "" {
+		w.Int64(-1)
+		return false
+	}
+
+	// For a defined symbol, export its index.
+	// For re-exporting an imported symbol, pass its index through.
+	w.Int64(int64(lsym.SymIdx))
+	return true
+}
diff --git a/src/cmd/compile/internal/noder/noder.go b/src/cmd/compile/internal/noder/noder.go
new file mode 100644
index 0000000..c99c085
--- /dev/null
+++ b/src/cmd/compile/internal/noder/noder.go
@@ -0,0 +1,496 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/internal/objabi"
+	"cmd/internal/src"
+)
+
+func LoadPackage(filenames []string) {
+	base.Timer.Start("fe", "parse")
+
+	// Limit the number of simultaneously open files.
+	sem := make(chan struct{}, runtime.GOMAXPROCS(0)+10)
+
+	noders := make([]*noder, len(filenames))
+	for i := range noders {
+		p := noder{
+			err: make(chan syntax.Error),
+		}
+		noders[i] = &p
+	}
+
+	// Move the entire syntax processing logic into a separate goroutine to avoid blocking on the "sem".
+	go func() {
+		for i, filename := range filenames {
+			filename := filename
+			p := noders[i]
+			sem <- struct{}{}
+			go func() {
+				defer func() { <-sem }()
+				defer close(p.err)
+				fbase := syntax.NewFileBase(filename)
+
+				f, err := os.Open(filename)
+				if err != nil {
+					p.error(syntax.Error{Msg: err.Error()})
+					return
+				}
+				defer f.Close()
+
+				p.file, _ = syntax.Parse(fbase, f, p.error, p.pragma, syntax.CheckBranches) // errors are tracked via p.error
+			}()
+		}
+	}()
+
+	var lines uint
+	for _, p := range noders {
+		for e := range p.err {
+			p.errorAt(e.Pos, "%s", e.Msg)
+		}
+		if p.file == nil {
+			base.ErrorExit()
+		}
+		lines += p.file.EOF.Line()
+	}
+	base.Timer.AddEvent(int64(lines), "lines")
+
+	if base.Debug.Unified != 0 {
+		unified(noders)
+		return
+	}
+
+	// Use types2 to type-check and generate IR.
+	check2(noders)
+}
+
+func (p *noder) errorAt(pos syntax.Pos, format string, args ...interface{}) {
+	base.ErrorfAt(p.makeXPos(pos), format, args...)
+}
+
+// trimFilename returns the "trimmed" filename of b, which is the
+// absolute filename after applying -trimpath processing. This
+// filename form is suitable for use in object files and export data.
+//
+// If b's filename has already been trimmed (i.e., because it was read
+// in from an imported package's export data), then the filename is
+// returned unchanged.
+func trimFilename(b *syntax.PosBase) string {
+	filename := b.Filename()
+	if !b.Trimmed() {
+		dir := ""
+		if b.IsFileBase() {
+			dir = base.Ctxt.Pathname
+		}
+		filename = objabi.AbsFile(dir, filename, base.Flag.TrimPath)
+	}
+	return filename
+}
+
+// noder transforms package syntax's AST into a Node tree.
+type noder struct {
+	posMap
+
+	file           *syntax.File
+	linknames      []linkname
+	pragcgobuf     [][]string
+	err            chan syntax.Error
+	importedUnsafe bool
+	importedEmbed  bool
+}
+
+// linkname records a //go:linkname directive.
+type linkname struct {
+	pos    syntax.Pos
+	local  string
+	remote string
+}
+
+func (p *noder) processPragmas() {
+	for _, l := range p.linknames {
+		if !p.importedUnsafe {
+			p.errorAt(l.pos, "//go:linkname only allowed in Go files that import \"unsafe\"")
+			continue
+		}
+		n := ir.AsNode(typecheck.Lookup(l.local).Def)
+		if n == nil || n.Op() != ir.ONAME {
+			if types.AllowsGoVersion(1, 18) {
+				p.errorAt(l.pos, "//go:linkname must refer to declared function or variable")
+			}
+			continue
+		}
+		if n.Sym().Linkname != "" {
+			p.errorAt(l.pos, "duplicate //go:linkname for %s", l.local)
+			continue
+		}
+		n.Sym().Linkname = l.remote
+	}
+	typecheck.Target.CgoPragmas = append(typecheck.Target.CgoPragmas, p.pragcgobuf...)
+}
+
+var unOps = [...]ir.Op{
+	syntax.Recv: ir.ORECV,
+	syntax.Mul:  ir.ODEREF,
+	syntax.And:  ir.OADDR,
+
+	syntax.Not: ir.ONOT,
+	syntax.Xor: ir.OBITNOT,
+	syntax.Add: ir.OPLUS,
+	syntax.Sub: ir.ONEG,
+}
+
+var binOps = [...]ir.Op{
+	syntax.OrOr:   ir.OOROR,
+	syntax.AndAnd: ir.OANDAND,
+
+	syntax.Eql: ir.OEQ,
+	syntax.Neq: ir.ONE,
+	syntax.Lss: ir.OLT,
+	syntax.Leq: ir.OLE,
+	syntax.Gtr: ir.OGT,
+	syntax.Geq: ir.OGE,
+
+	syntax.Add: ir.OADD,
+	syntax.Sub: ir.OSUB,
+	syntax.Or:  ir.OOR,
+	syntax.Xor: ir.OXOR,
+
+	syntax.Mul:    ir.OMUL,
+	syntax.Div:    ir.ODIV,
+	syntax.Rem:    ir.OMOD,
+	syntax.And:    ir.OAND,
+	syntax.AndNot: ir.OANDNOT,
+	syntax.Shl:    ir.OLSH,
+	syntax.Shr:    ir.ORSH,
+}
+
+func wrapname(pos src.XPos, x ir.Node) ir.Node {
+	// These nodes do not carry line numbers.
+	// Introduce a wrapper node to give them the correct line.
+	switch x.Op() {
+	case ir.OTYPE, ir.OLITERAL:
+		if x.Sym() == nil {
+			break
+		}
+		fallthrough
+	case ir.ONAME, ir.ONONAME:
+		p := ir.NewParenExpr(pos, x)
+		p.SetImplicit(true)
+		return p
+	}
+	return x
+}
+
+// error is called concurrently if files are parsed concurrently.
+func (p *noder) error(err error) {
+	p.err <- err.(syntax.Error)
+}
+
+// pragmas that are allowed in the std lib, but don't have
+// a syntax.Pragma value (see lex.go) associated with them.
+var allowedStdPragmas = map[string]bool{
+	"go:cgo_export_static":  true,
+	"go:cgo_export_dynamic": true,
+	"go:cgo_import_static":  true,
+	"go:cgo_import_dynamic": true,
+	"go:cgo_ldflag":         true,
+	"go:cgo_dynamic_linker": true,
+	"go:embed":              true,
+	"go:generate":           true,
+}
+
+// *pragmas is the value stored in a syntax.pragmas during parsing.
+type pragmas struct {
+	Flag   ir.PragmaFlag // collected bits
+	Pos    []pragmaPos   // position of each individual flag
+	Embeds []pragmaEmbed
+}
+
+type pragmaPos struct {
+	Flag ir.PragmaFlag
+	Pos  syntax.Pos
+}
+
+type pragmaEmbed struct {
+	Pos      syntax.Pos
+	Patterns []string
+}
+
+func (p *noder) checkUnusedDuringParse(pragma *pragmas) {
+	for _, pos := range pragma.Pos {
+		if pos.Flag&pragma.Flag != 0 {
+			p.error(syntax.Error{Pos: pos.Pos, Msg: "misplaced compiler directive"})
+		}
+	}
+	if len(pragma.Embeds) > 0 {
+		for _, e := range pragma.Embeds {
+			p.error(syntax.Error{Pos: e.Pos, Msg: "misplaced go:embed directive"})
+		}
+	}
+}
+
+// pragma is called concurrently if files are parsed concurrently.
+func (p *noder) pragma(pos syntax.Pos, blankLine bool, text string, old syntax.Pragma) syntax.Pragma {
+	pragma, _ := old.(*pragmas)
+	if pragma == nil {
+		pragma = new(pragmas)
+	}
+
+	if text == "" {
+		// unused pragma; only called with old != nil.
+		p.checkUnusedDuringParse(pragma)
+		return nil
+	}
+
+	if strings.HasPrefix(text, "line ") {
+		// line directives are handled by syntax package
+		panic("unreachable")
+	}
+
+	if !blankLine {
+		// directive must be on line by itself
+		p.error(syntax.Error{Pos: pos, Msg: "misplaced compiler directive"})
+		return pragma
+	}
+
+	switch {
+	case strings.HasPrefix(text, "go:linkname "):
+		f := strings.Fields(text)
+		if !(2 <= len(f) && len(f) <= 3) {
+			p.error(syntax.Error{Pos: pos, Msg: "usage: //go:linkname localname [linkname]"})
+			break
+		}
+		// The second argument is optional. If omitted, we use
+		// the default object symbol name for this and
+		// linkname only serves to mark this symbol as
+		// something that may be referenced via the object
+		// symbol name from another package.
+		var target string
+		if len(f) == 3 {
+			target = f[2]
+		} else if base.Ctxt.Pkgpath != "" {
+			// Use the default object symbol name if the
+			// user didn't provide one.
+			target = objabi.PathToPrefix(base.Ctxt.Pkgpath) + "." + f[1]
+		} else {
+			p.error(syntax.Error{Pos: pos, Msg: "//go:linkname requires linkname argument or -p compiler flag"})
+			break
+		}
+		p.linknames = append(p.linknames, linkname{pos, f[1], target})
+
+	case text == "go:embed", strings.HasPrefix(text, "go:embed "):
+		args, err := parseGoEmbed(text[len("go:embed"):])
+		if err != nil {
+			p.error(syntax.Error{Pos: pos, Msg: err.Error()})
+		}
+		if len(args) == 0 {
+			p.error(syntax.Error{Pos: pos, Msg: "usage: //go:embed pattern..."})
+			break
+		}
+		pragma.Embeds = append(pragma.Embeds, pragmaEmbed{pos, args})
+
+	case strings.HasPrefix(text, "go:cgo_import_dynamic "):
+		// This is permitted for general use because Solaris
+		// code relies on it in golang.org/x/sys/unix and others.
+		fields := pragmaFields(text)
+		if len(fields) >= 4 {
+			lib := strings.Trim(fields[3], `"`)
+			if lib != "" && !safeArg(lib) && !isCgoGeneratedFile(pos) {
+				p.error(syntax.Error{Pos: pos, Msg: fmt.Sprintf("invalid library name %q in cgo_import_dynamic directive", lib)})
+			}
+			p.pragcgo(pos, text)
+			pragma.Flag |= pragmaFlag("go:cgo_import_dynamic")
+			break
+		}
+		fallthrough
+	case strings.HasPrefix(text, "go:cgo_"):
+		// For security, we disallow //go:cgo_* directives other
+		// than cgo_import_dynamic outside cgo-generated files.
+		// Exception: they are allowed in the standard library, for runtime and syscall.
+		if !isCgoGeneratedFile(pos) && !base.Flag.Std {
+			p.error(syntax.Error{Pos: pos, Msg: fmt.Sprintf("//%s only allowed in cgo-generated code", text)})
+		}
+		p.pragcgo(pos, text)
+		fallthrough // because of //go:cgo_unsafe_args
+	default:
+		verb := text
+		if i := strings.Index(text, " "); i >= 0 {
+			verb = verb[:i]
+		}
+		flag := pragmaFlag(verb)
+		const runtimePragmas = ir.Systemstack | ir.Nowritebarrier | ir.Nowritebarrierrec | ir.Yeswritebarrierrec
+		if !base.Flag.CompilingRuntime && flag&runtimePragmas != 0 {
+			p.error(syntax.Error{Pos: pos, Msg: fmt.Sprintf("//%s only allowed in runtime", verb)})
+		}
+		if flag == ir.UintptrKeepAlive && !base.Flag.Std {
+			p.error(syntax.Error{Pos: pos, Msg: fmt.Sprintf("//%s is only allowed in the standard library", verb)})
+		}
+		if flag == 0 && !allowedStdPragmas[verb] && base.Flag.Std {
+			p.error(syntax.Error{Pos: pos, Msg: fmt.Sprintf("//%s is not allowed in the standard library", verb)})
+		}
+		pragma.Flag |= flag
+		pragma.Pos = append(pragma.Pos, pragmaPos{flag, pos})
+	}
+
+	return pragma
+}
+
+// isCgoGeneratedFile reports whether pos is in a file
+// generated by cgo, which is to say a file with name
+// beginning with "_cgo_". Such files are allowed to
+// contain cgo directives, and for security reasons
+// (primarily misuse of linker flags), other files are not.
+// See golang.org/issue/23672.
+// Note that cmd/go ignores files whose names start with underscore,
+// so the only _cgo_ files we will see from cmd/go are generated by cgo.
+// It's easy to bypass this check by calling the compiler directly;
+// we only protect against uses by cmd/go.
+func isCgoGeneratedFile(pos syntax.Pos) bool {
+	// We need the absolute file, independent of //line directives,
+	// so we call pos.Base().Pos().
+	return strings.HasPrefix(filepath.Base(trimFilename(pos.Base().Pos().Base())), "_cgo_")
+}
+
+// safeArg reports whether arg is a "safe" command-line argument,
+// meaning that when it appears in a command-line, it probably
+// doesn't have some special meaning other than its own name.
+// This is copied from SafeArg in cmd/go/internal/load/pkg.go.
+func safeArg(name string) bool {
+	if name == "" {
+		return false
+	}
+	c := name[0]
+	return '0' <= c && c <= '9' || 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z' || c == '.' || c == '_' || c == '/' || c >= utf8.RuneSelf
+}
+
+// parseGoEmbed parses the text following "//go:embed" to extract the glob patterns.
+// It accepts unquoted space-separated patterns as well as double-quoted and back-quoted Go strings.
+// go/build/read.go also processes these strings and contains similar logic.
+func parseGoEmbed(args string) ([]string, error) {
+	var list []string
+	for args = strings.TrimSpace(args); args != ""; args = strings.TrimSpace(args) {
+		var path string
+	Switch:
+		switch args[0] {
+		default:
+			i := len(args)
+			for j, c := range args {
+				if unicode.IsSpace(c) {
+					i = j
+					break
+				}
+			}
+			path = args[:i]
+			args = args[i:]
+
+		case '`':
+			i := strings.Index(args[1:], "`")
+			if i < 0 {
+				return nil, fmt.Errorf("invalid quoted string in //go:embed: %s", args)
+			}
+			path = args[1 : 1+i]
+			args = args[1+i+1:]
+
+		case '"':
+			i := 1
+			for ; i < len(args); i++ {
+				if args[i] == '\\' {
+					i++
+					continue
+				}
+				if args[i] == '"' {
+					q, err := strconv.Unquote(args[:i+1])
+					if err != nil {
+						return nil, fmt.Errorf("invalid quoted string in //go:embed: %s", args[:i+1])
+					}
+					path = q
+					args = args[i+1:]
+					break Switch
+				}
+			}
+			if i >= len(args) {
+				return nil, fmt.Errorf("invalid quoted string in //go:embed: %s", args)
+			}
+		}
+
+		if args != "" {
+			r, _ := utf8.DecodeRuneInString(args)
+			if !unicode.IsSpace(r) {
+				return nil, fmt.Errorf("invalid quoted string in //go:embed: %s", args)
+			}
+		}
+		list = append(list, path)
+	}
+	return list, nil
+}
+
+// A function named init is a special case.
+// It is called by the initialization before main is run.
+// To make it unique within a package and also uncallable,
+// the name, normally "pkg.init", is altered to "pkg.init.0".
+var renameinitgen int
+
+func Renameinit() *types.Sym {
+	s := typecheck.LookupNum("init.", renameinitgen)
+	renameinitgen++
+	return s
+}
+
+func varEmbed(makeXPos func(syntax.Pos) src.XPos, name *ir.Name, decl *syntax.VarDecl, pragma *pragmas, haveEmbed bool) {
+	pragmaEmbeds := pragma.Embeds
+	pragma.Embeds = nil
+	if len(pragmaEmbeds) == 0 {
+		return
+	}
+
+	if err := checkEmbed(decl, haveEmbed, typecheck.DeclContext != ir.PEXTERN); err != nil {
+		base.ErrorfAt(makeXPos(pragmaEmbeds[0].Pos), "%s", err)
+		return
+	}
+
+	var embeds []ir.Embed
+	for _, e := range pragmaEmbeds {
+		embeds = append(embeds, ir.Embed{Pos: makeXPos(e.Pos), Patterns: e.Patterns})
+	}
+	typecheck.Target.Embeds = append(typecheck.Target.Embeds, name)
+	name.Embed = &embeds
+}
+
+func checkEmbed(decl *syntax.VarDecl, haveEmbed, withinFunc bool) error {
+	switch {
+	case !haveEmbed:
+		return errors.New("go:embed only allowed in Go files that import \"embed\"")
+	case len(decl.NameList) > 1:
+		return errors.New("go:embed cannot apply to multiple vars")
+	case decl.Values != nil:
+		return errors.New("go:embed cannot apply to var with initializer")
+	case decl.Type == nil:
+		// Should not happen, since Values == nil now.
+		return errors.New("go:embed cannot apply to var without type")
+	case withinFunc:
+		return errors.New("go:embed cannot apply to var inside func")
+	case !types.AllowsGoVersion(1, 16):
+		return fmt.Errorf("go:embed requires go1.16 or later (-lang was set to %s; check go.mod)", base.Flag.Lang)
+
+	default:
+		return nil
+	}
+}
diff --git a/src/cmd/compile/internal/noder/object.go b/src/cmd/compile/internal/noder/object.go
new file mode 100644
index 0000000..3b60760
--- /dev/null
+++ b/src/cmd/compile/internal/noder/object.go
@@ -0,0 +1,205 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+	"cmd/internal/src"
+)
+
+func (g *irgen) def(name *syntax.Name) (*ir.Name, types2.Object) {
+	obj, ok := g.info.Defs[name]
+	if !ok {
+		base.FatalfAt(g.pos(name), "unknown name %v", name)
+	}
+	return g.obj(obj), obj
+}
+
+// use returns the Name or InstExpr node associated with the use of name,
+// possibly instantiated by type arguments. The returned node will have
+// the correct type and be marked as typechecked.
+func (g *irgen) use(name *syntax.Name) ir.Node {
+	obj2, ok := g.info.Uses[name]
+	if !ok {
+		base.FatalfAt(g.pos(name), "unknown name %v", name)
+	}
+	obj := ir.CaptureName(g.pos(name), ir.CurFunc, g.obj(obj2))
+	if obj.Defn != nil && obj.Defn.Op() == ir.ONAME {
+		// If CaptureName created a closure variable, then transfer the
+		// type of the captured name to the new closure variable.
+		obj.SetTypecheck(1)
+		obj.SetType(obj.Defn.Type())
+	}
+
+	if obj.Class == ir.PFUNC {
+		if inst, ok := g.info.Instances[name]; ok {
+			// This is the case where inferring types required the
+			// types of the function arguments.
+			targs := make([]ir.Ntype, inst.TypeArgs.Len())
+			for i := range targs {
+				targs[i] = ir.TypeNode(g.typ(inst.TypeArgs.At(i)))
+			}
+			typ := g.substType(obj.Type(), obj.Type().TParams(), targs)
+			return typed(typ, ir.NewInstExpr(g.pos(name), ir.OFUNCINST, obj, targs))
+		}
+	}
+
+	return obj
+}
+
+// obj returns the Name that represents the given object. If no such Name exists
+// yet, it will be implicitly created. The returned node will have the correct
+// type and be marked as typechecked.
+//
+// For objects declared at function scope, ir.CurFunc must already be
+// set to the respective function when the Name is created.
+func (g *irgen) obj(obj types2.Object) *ir.Name {
+	// For imported objects, we use iimport directly instead of mapping
+	// the types2 representation.
+	if obj.Pkg() != g.self {
+		if sig, ok := obj.Type().(*types2.Signature); ok && sig.Recv() != nil {
+			// We can't import a method by name - must import the type
+			// and access the method from it.
+			base.FatalfAt(g.pos(obj), "tried to import a method directly")
+		}
+		sym := g.sym(obj)
+		if sym.Def != nil {
+			return sym.Def.(*ir.Name)
+		}
+		n := typecheck.Resolve(ir.NewIdent(src.NoXPos, sym))
+		if n, ok := n.(*ir.Name); ok {
+			n.SetTypecheck(1)
+			return n
+		}
+		base.FatalfAt(g.pos(obj), "failed to resolve %v", obj)
+	}
+
+	if name, ok := g.objs[obj]; ok {
+		return name // previously mapped
+	}
+
+	var name *ir.Name
+	pos := g.pos(obj)
+
+	class := typecheck.DeclContext
+	if obj.Parent() == g.self.Scope() {
+		class = ir.PEXTERN // forward reference to package-block declaration
+	}
+
+	// "You are in a maze of twisting little passages, all different."
+	switch obj := obj.(type) {
+	case *types2.Const:
+		name = g.objCommon(pos, ir.OLITERAL, g.sym(obj), class, g.typ(obj.Type()))
+
+	case *types2.Func:
+		sig := obj.Type().(*types2.Signature)
+		var sym *types.Sym
+		var typ *types.Type
+		if recv := sig.Recv(); recv == nil {
+			if obj.Name() == "init" {
+				sym = Renameinit()
+			} else {
+				sym = g.sym(obj)
+			}
+			typ = g.typ(sig)
+		} else {
+			sym = g.selector(obj)
+			if !sym.IsBlank() {
+				sym = ir.MethodSym(g.typ(recv.Type()), sym)
+			}
+			typ = g.signature(g.param(recv), sig)
+		}
+		name = g.objCommon(pos, ir.ONAME, sym, ir.PFUNC, typ)
+
+	case *types2.TypeName:
+		if obj.IsAlias() {
+			name = g.objCommon(pos, ir.OTYPE, g.sym(obj), class, g.typ(obj.Type()))
+			name.SetAlias(true)
+		} else {
+			name = ir.NewDeclNameAt(pos, ir.OTYPE, g.sym(obj))
+			g.objFinish(name, class, types.NewNamed(name))
+		}
+
+	case *types2.Var:
+		sym := g.sym(obj)
+		if class == ir.PPARAMOUT && (sym == nil || sym.IsBlank()) {
+			// Backend needs names for result parameters,
+			// even if they're anonymous or blank.
+			nresults := 0
+			for _, n := range ir.CurFunc.Dcl {
+				if n.Class == ir.PPARAMOUT {
+					nresults++
+				}
+			}
+			if sym == nil {
+				sym = typecheck.LookupNum("~r", nresults) // 'r' for "result"
+			} else {
+				sym = typecheck.LookupNum("~b", nresults) // 'b' for "blank"
+			}
+		}
+		name = g.objCommon(pos, ir.ONAME, sym, class, g.typ(obj.Type()))
+
+	default:
+		g.unhandled("object", obj)
+	}
+
+	g.objs[obj] = name
+	name.SetTypecheck(1)
+	return name
+}
+
+func (g *irgen) objCommon(pos src.XPos, op ir.Op, sym *types.Sym, class ir.Class, typ *types.Type) *ir.Name {
+	name := ir.NewDeclNameAt(pos, op, sym)
+	g.objFinish(name, class, typ)
+	return name
+}
+
+func (g *irgen) objFinish(name *ir.Name, class ir.Class, typ *types.Type) {
+	sym := name.Sym()
+
+	name.SetType(typ)
+	name.Class = class
+	if name.Class == ir.PFUNC {
+		sym.SetFunc(true)
+	}
+
+	name.SetTypecheck(1)
+
+	if ir.IsBlank(name) {
+		return
+	}
+
+	switch class {
+	case ir.PEXTERN:
+		g.target.Externs = append(g.target.Externs, name)
+		fallthrough
+	case ir.PFUNC:
+		sym.Def = name
+		if name.Class == ir.PFUNC && name.Type().Recv() != nil {
+			break // methods are exported with their receiver type
+		}
+		if types.IsExported(sym.Name) {
+			// Generic functions can be marked for export here, even
+			// though they will not be compiled until instantiated.
+			typecheck.Export(name)
+		}
+		if base.Flag.AsmHdr != "" && !name.Sym().Asm() {
+			name.Sym().SetAsm(true)
+			g.target.Asms = append(g.target.Asms, name)
+		}
+
+	default:
+		// Function-scoped declaration.
+		name.Curfn = ir.CurFunc
+		if name.Op() == ir.ONAME {
+			ir.CurFunc.Dcl = append(ir.CurFunc.Dcl, name)
+		}
+	}
+}
diff --git a/src/cmd/compile/internal/noder/posmap.go b/src/cmd/compile/internal/noder/posmap.go
new file mode 100644
index 0000000..6c7e57c
--- /dev/null
+++ b/src/cmd/compile/internal/noder/posmap.go
@@ -0,0 +1,86 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/syntax"
+	"cmd/internal/src"
+)
+
+// A posMap handles mapping from syntax.Pos to src.XPos.
+type posMap struct {
+	bases map[*syntax.PosBase]*src.PosBase
+	cache struct {
+		last *syntax.PosBase
+		base *src.PosBase
+	}
+}
+
+type poser interface{ Pos() syntax.Pos }
+type ender interface{ End() syntax.Pos }
+
+func (m *posMap) pos(p poser) src.XPos { return m.makeXPos(p.Pos()) }
+func (m *posMap) end(p ender) src.XPos { return m.makeXPos(p.End()) }
+
+func (m *posMap) makeXPos(pos syntax.Pos) src.XPos {
+	// Predeclared objects (e.g., the result parameter for error.Error)
+	// do not have a position.
+	if !pos.IsKnown() {
+		return src.NoXPos
+	}
+
+	posBase := m.makeSrcPosBase(pos.Base())
+	return base.Ctxt.PosTable.XPos(src.MakePos(posBase, pos.Line(), pos.Col()))
+}
+
+// makeSrcPosBase translates from a *syntax.PosBase to a *src.PosBase.
+func (m *posMap) makeSrcPosBase(b0 *syntax.PosBase) *src.PosBase {
+	// fast path: most likely PosBase hasn't changed
+	if m.cache.last == b0 {
+		return m.cache.base
+	}
+
+	b1, ok := m.bases[b0]
+	if !ok {
+		fn := b0.Filename()
+		absfn := trimFilename(b0)
+
+		if b0.IsFileBase() {
+			b1 = src.NewFileBase(fn, absfn)
+		} else {
+			// line directive base
+			p0 := b0.Pos()
+			p0b := p0.Base()
+			if p0b == b0 {
+				panic("infinite recursion in makeSrcPosBase")
+			}
+			p1 := src.MakePos(m.makeSrcPosBase(p0b), p0.Line(), p0.Col())
+			b1 = src.NewLinePragmaBase(p1, fn, absfn, b0.Line(), b0.Col())
+		}
+		if m.bases == nil {
+			m.bases = make(map[*syntax.PosBase]*src.PosBase)
+		}
+		m.bases[b0] = b1
+	}
+
+	// update cache
+	m.cache.last = b0
+	m.cache.base = b1
+
+	return b1
+}
+
+func (m *posMap) join(other *posMap) {
+	if m.bases == nil {
+		m.bases = make(map[*syntax.PosBase]*src.PosBase)
+	}
+	for k, v := range other.bases {
+		if m.bases[k] != nil {
+			base.Fatalf("duplicate posmap bases")
+		}
+		m.bases[k] = v
+	}
+}
diff --git a/src/cmd/compile/internal/noder/quirks.go b/src/cmd/compile/internal/noder/quirks.go
new file mode 100644
index 0000000..a22577f
--- /dev/null
+++ b/src/cmd/compile/internal/noder/quirks.go
@@ -0,0 +1,79 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+
+	"cmd/compile/internal/syntax"
+)
+
+// typeExprEndPos returns the position that noder would leave base.Pos
+// after parsing the given type expression.
+//
+// Deprecated: This function exists to emulate position semantics from
+// Go 1.17, necessary for compatibility with the backend DWARF
+// generation logic that assigns variables to their appropriate scope.
+func typeExprEndPos(expr0 syntax.Expr) syntax.Pos {
+	for {
+		switch expr := expr0.(type) {
+		case *syntax.Name:
+			return expr.Pos()
+		case *syntax.SelectorExpr:
+			return expr.X.Pos()
+
+		case *syntax.ParenExpr:
+			expr0 = expr.X
+
+		case *syntax.Operation:
+			assert(expr.Op == syntax.Mul)
+			assert(expr.Y == nil)
+			expr0 = expr.X
+
+		case *syntax.ArrayType:
+			expr0 = expr.Elem
+		case *syntax.ChanType:
+			expr0 = expr.Elem
+		case *syntax.DotsType:
+			expr0 = expr.Elem
+		case *syntax.MapType:
+			expr0 = expr.Value
+		case *syntax.SliceType:
+			expr0 = expr.Elem
+
+		case *syntax.StructType:
+			return expr.Pos()
+
+		case *syntax.InterfaceType:
+			expr0 = lastFieldType(expr.MethodList)
+			if expr0 == nil {
+				return expr.Pos()
+			}
+
+		case *syntax.FuncType:
+			expr0 = lastFieldType(expr.ResultList)
+			if expr0 == nil {
+				expr0 = lastFieldType(expr.ParamList)
+				if expr0 == nil {
+					return expr.Pos()
+				}
+			}
+
+		case *syntax.IndexExpr: // explicit type instantiation
+			targs := unpackListExpr(expr.Index)
+			expr0 = targs[len(targs)-1]
+
+		default:
+			panic(fmt.Sprintf("%s: unexpected type expression %v", expr.Pos(), syntax.String(expr)))
+		}
+	}
+}
+
+func lastFieldType(fields []*syntax.Field) syntax.Expr {
+	if len(fields) == 0 {
+		return nil
+	}
+	return fields[len(fields)-1].Type
+}
diff --git a/src/cmd/compile/internal/noder/reader.go b/src/cmd/compile/internal/noder/reader.go
new file mode 100644
index 0000000..bc2151e
--- /dev/null
+++ b/src/cmd/compile/internal/noder/reader.go
@@ -0,0 +1,4029 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+	"go/constant"
+	"internal/buildcfg"
+	"internal/pkgbits"
+	"strings"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/deadcode"
+	"cmd/compile/internal/dwarfgen"
+	"cmd/compile/internal/inline"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/objw"
+	"cmd/compile/internal/reflectdata"
+	"cmd/compile/internal/staticinit"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/internal/obj"
+	"cmd/internal/objabi"
+	"cmd/internal/src"
+)
+
+// This file implements cmd/compile backend's reader for the Unified
+// IR export data.
+
+// A pkgReader reads Unified IR export data.
+type pkgReader struct {
+	pkgbits.PkgDecoder
+
+	// Indices for encoded things; lazily populated as needed.
+	//
+	// Note: Objects (i.e., ir.Names) are lazily instantiated by
+	// populating their types.Sym.Def; see objReader below.
+
+	posBases []*src.PosBase
+	pkgs     []*types.Pkg
+	typs     []*types.Type
+
+	// offset for rewriting the given (absolute!) index into the output,
+	// but bitwise inverted so we can detect if we're missing the entry
+	// or not.
+	newindex []pkgbits.Index
+}
+
+func newPkgReader(pr pkgbits.PkgDecoder) *pkgReader {
+	return &pkgReader{
+		PkgDecoder: pr,
+
+		posBases: make([]*src.PosBase, pr.NumElems(pkgbits.RelocPosBase)),
+		pkgs:     make([]*types.Pkg, pr.NumElems(pkgbits.RelocPkg)),
+		typs:     make([]*types.Type, pr.NumElems(pkgbits.RelocType)),
+
+		newindex: make([]pkgbits.Index, pr.TotalElems()),
+	}
+}
+
+// A pkgReaderIndex compactly identifies an index (and its
+// corresponding dictionary) within a package's export data.
+type pkgReaderIndex struct {
+	pr        *pkgReader
+	idx       pkgbits.Index
+	dict      *readerDict
+	methodSym *types.Sym
+
+	synthetic func(pos src.XPos, r *reader)
+}
+
+func (pri pkgReaderIndex) asReader(k pkgbits.RelocKind, marker pkgbits.SyncMarker) *reader {
+	if pri.synthetic != nil {
+		return &reader{synthetic: pri.synthetic}
+	}
+
+	r := pri.pr.newReader(k, pri.idx, marker)
+	r.dict = pri.dict
+	r.methodSym = pri.methodSym
+	return r
+}
+
+func (pr *pkgReader) newReader(k pkgbits.RelocKind, idx pkgbits.Index, marker pkgbits.SyncMarker) *reader {
+	return &reader{
+		Decoder: pr.NewDecoder(k, idx, marker),
+		p:       pr,
+	}
+}
+
+// A reader provides APIs for reading an individual element.
+type reader struct {
+	pkgbits.Decoder
+
+	p *pkgReader
+
+	dict *readerDict
+
+	// TODO(mdempsky): The state below is all specific to reading
+	// function bodies. It probably makes sense to split it out
+	// separately so that it doesn't take up space in every reader
+	// instance.
+
+	curfn       *ir.Func
+	locals      []*ir.Name
+	closureVars []*ir.Name
+
+	funarghack bool
+
+	// methodSym is the name of method's name, if reading a method.
+	// It's nil if reading a normal function or closure body.
+	methodSym *types.Sym
+
+	// dictParam is the .dict param, if any.
+	dictParam *ir.Name
+
+	// synthetic is a callback function to construct a synthetic
+	// function body. It's used for creating the bodies of function
+	// literals used to curry arguments to shaped functions.
+	synthetic func(pos src.XPos, r *reader)
+
+	// scopeVars is a stack tracking the number of variables declared in
+	// the current function at the moment each open scope was opened.
+	scopeVars         []int
+	marker            dwarfgen.ScopeMarker
+	lastCloseScopePos src.XPos
+
+	// === details for handling inline body expansion ===
+
+	// If we're reading in a function body because of inlining, this is
+	// the call that we're inlining for.
+	inlCaller    *ir.Func
+	inlCall      *ir.CallExpr
+	inlFunc      *ir.Func
+	inlTreeIndex int
+	inlPosBases  map[*src.PosBase]*src.PosBase
+
+	// suppressInlPos tracks whether position base rewriting for
+	// inlining should be suppressed. See funcLit.
+	suppressInlPos int
+
+	delayResults bool
+
+	// Label to return to.
+	retlabel *types.Sym
+
+	// inlvars is the list of variables that the inlinee's arguments are
+	// assigned to, one for each receiver and normal parameter, in order.
+	inlvars ir.Nodes
+
+	// retvars is the list of variables that the inlinee's results are
+	// assigned to, one for each result parameter, in order.
+	retvars ir.Nodes
+}
+
+// A readerDict represents an instantiated "compile-time dictionary,"
+// used for resolving any derived types needed for instantiating a
+// generic object.
+//
+// A compile-time dictionary can either be "shaped" or "non-shaped."
+// Shaped compile-time dictionaries are only used for instantiating
+// shaped type definitions and function bodies, while non-shaped
+// compile-time dictionaries are used for instantiating runtime
+// dictionaries.
+type readerDict struct {
+	shaped bool // whether this is a shaped dictionary
+
+	// baseSym is the symbol for the object this dictionary belongs to.
+	// If the object is an instantiated function or defined type, then
+	// baseSym is the mangled symbol, including any type arguments.
+	baseSym *types.Sym
+
+	// For non-shaped dictionaries, shapedObj is a reference to the
+	// corresponding shaped object (always a function or defined type).
+	shapedObj *ir.Name
+
+	// targs holds the implicit and explicit type arguments in use for
+	// reading the current object. For example:
+	//
+	//	func F[T any]() {
+	//		type X[U any] struct { t T; u U }
+	//		var _ X[string]
+	//	}
+	//
+	//	var _ = F[int]
+	//
+	// While instantiating F[int], we need to in turn instantiate
+	// X[string]. [int] and [string] are explicit type arguments for F
+	// and X, respectively; but [int] is also the implicit type
+	// arguments for X.
+	//
+	// (As an analogy to function literals, explicits are the function
+	// literal's formal parameters, while implicits are variables
+	// captured by the function literal.)
+	targs []*types.Type
+
+	// implicits counts how many of types within targs are implicit type
+	// arguments; the rest are explicit.
+	implicits int
+
+	derived      []derivedInfo // reloc index of the derived type's descriptor
+	derivedTypes []*types.Type // slice of previously computed derived types
+
+	// These slices correspond to entries in the runtime dictionary.
+	typeParamMethodExprs []readerMethodExprInfo
+	subdicts             []objInfo
+	rtypes               []typeInfo
+	itabs                []itabInfo
+}
+
+type readerMethodExprInfo struct {
+	typeParamIdx int
+	method       *types.Sym
+}
+
+func setType(n ir.Node, typ *types.Type) {
+	n.SetType(typ)
+	n.SetTypecheck(1)
+}
+
+func setValue(name *ir.Name, val constant.Value) {
+	name.SetVal(val)
+	name.Defn = nil
+}
+
+// @@@ Positions
+
+// pos reads a position from the bitstream.
+func (r *reader) pos() src.XPos {
+	return base.Ctxt.PosTable.XPos(r.pos0())
+}
+
+// origPos reads a position from the bitstream, and returns both the
+// original raw position and an inlining-adjusted position.
+func (r *reader) origPos() (origPos, inlPos src.XPos) {
+	r.suppressInlPos++
+	origPos = r.pos()
+	r.suppressInlPos--
+	inlPos = r.inlPos(origPos)
+	return
+}
+
+func (r *reader) pos0() src.Pos {
+	r.Sync(pkgbits.SyncPos)
+	if !r.Bool() {
+		return src.NoPos
+	}
+
+	posBase := r.posBase()
+	line := r.Uint()
+	col := r.Uint()
+	return src.MakePos(posBase, line, col)
+}
+
+// posBase reads a position base from the bitstream.
+func (r *reader) posBase() *src.PosBase {
+	return r.inlPosBase(r.p.posBaseIdx(r.Reloc(pkgbits.RelocPosBase)))
+}
+
+// posBaseIdx returns the specified position base, reading it first if
+// needed.
+func (pr *pkgReader) posBaseIdx(idx pkgbits.Index) *src.PosBase {
+	if b := pr.posBases[idx]; b != nil {
+		return b
+	}
+
+	r := pr.newReader(pkgbits.RelocPosBase, idx, pkgbits.SyncPosBase)
+	var b *src.PosBase
+
+	absFilename := r.String()
+	filename := absFilename
+
+	// For build artifact stability, the export data format only
+	// contains the "absolute" filename as returned by objabi.AbsFile.
+	// However, some tests (e.g., test/run.go's asmcheck tests) expect
+	// to see the full, original filename printed out. Re-expanding
+	// "$GOROOT" to buildcfg.GOROOT is a close-enough approximation to
+	// satisfy this.
+	//
+	// TODO(mdempsky): De-duplicate this logic with similar logic in
+	// cmd/link/internal/ld's expandGoroot. However, this will probably
+	// require being more consistent about when we use native vs UNIX
+	// file paths.
+	const dollarGOROOT = "$GOROOT"
+	if buildcfg.GOROOT != "" && strings.HasPrefix(filename, dollarGOROOT) {
+		filename = buildcfg.GOROOT + filename[len(dollarGOROOT):]
+	}
+
+	if r.Bool() {
+		b = src.NewFileBase(filename, absFilename)
+	} else {
+		pos := r.pos0()
+		line := r.Uint()
+		col := r.Uint()
+		b = src.NewLinePragmaBase(pos, filename, absFilename, line, col)
+	}
+
+	pr.posBases[idx] = b
+	return b
+}
+
+// inlPosBase returns the inlining-adjusted src.PosBase corresponding
+// to oldBase, which must be a non-inlined position. When not
+// inlining, this is just oldBase.
+func (r *reader) inlPosBase(oldBase *src.PosBase) *src.PosBase {
+	if index := oldBase.InliningIndex(); index >= 0 {
+		base.Fatalf("oldBase %v already has inlining index %v", oldBase, index)
+	}
+
+	if r.inlCall == nil || r.suppressInlPos != 0 {
+		return oldBase
+	}
+
+	if newBase, ok := r.inlPosBases[oldBase]; ok {
+		return newBase
+	}
+
+	newBase := src.NewInliningBase(oldBase, r.inlTreeIndex)
+	r.inlPosBases[oldBase] = newBase
+	return newBase
+}
+
+// inlPos returns the inlining-adjusted src.XPos corresponding to
+// xpos, which must be a non-inlined position. When not inlining, this
+// is just xpos.
+func (r *reader) inlPos(xpos src.XPos) src.XPos {
+	pos := base.Ctxt.PosTable.Pos(xpos)
+	pos.SetBase(r.inlPosBase(pos.Base()))
+	return base.Ctxt.PosTable.XPos(pos)
+}
+
+// @@@ Packages
+
+// pkg reads a package reference from the bitstream.
+func (r *reader) pkg() *types.Pkg {
+	r.Sync(pkgbits.SyncPkg)
+	return r.p.pkgIdx(r.Reloc(pkgbits.RelocPkg))
+}
+
+// pkgIdx returns the specified package from the export data, reading
+// it first if needed.
+func (pr *pkgReader) pkgIdx(idx pkgbits.Index) *types.Pkg {
+	if pkg := pr.pkgs[idx]; pkg != nil {
+		return pkg
+	}
+
+	pkg := pr.newReader(pkgbits.RelocPkg, idx, pkgbits.SyncPkgDef).doPkg()
+	pr.pkgs[idx] = pkg
+	return pkg
+}
+
+// doPkg reads a package definition from the bitstream.
+func (r *reader) doPkg() *types.Pkg {
+	path := r.String()
+	switch path {
+	case "":
+		path = r.p.PkgPath()
+	case "builtin":
+		return types.BuiltinPkg
+	case "unsafe":
+		return types.UnsafePkg
+	}
+
+	name := r.String()
+
+	pkg := types.NewPkg(path, "")
+
+	if pkg.Name == "" {
+		pkg.Name = name
+	} else {
+		base.Assertf(pkg.Name == name, "package %q has name %q, but want %q", pkg.Path, pkg.Name, name)
+	}
+
+	return pkg
+}
+
+// @@@ Types
+
+func (r *reader) typ() *types.Type {
+	return r.typWrapped(true)
+}
+
+// typWrapped is like typ, but allows suppressing generation of
+// unnecessary wrappers as a compile-time optimization.
+func (r *reader) typWrapped(wrapped bool) *types.Type {
+	return r.p.typIdx(r.typInfo(), r.dict, wrapped)
+}
+
+func (r *reader) typInfo() typeInfo {
+	r.Sync(pkgbits.SyncType)
+	if r.Bool() {
+		return typeInfo{idx: pkgbits.Index(r.Len()), derived: true}
+	}
+	return typeInfo{idx: r.Reloc(pkgbits.RelocType), derived: false}
+}
+
+// typListIdx returns a list of the specified types, resolving derived
+// types within the given dictionary.
+func (pr *pkgReader) typListIdx(infos []typeInfo, dict *readerDict) []*types.Type {
+	typs := make([]*types.Type, len(infos))
+	for i, info := range infos {
+		typs[i] = pr.typIdx(info, dict, true)
+	}
+	return typs
+}
+
+// typIdx returns the specified type. If info specifies a derived
+// type, it's resolved within the given dictionary. If wrapped is
+// true, then method wrappers will be generated, if appropriate.
+func (pr *pkgReader) typIdx(info typeInfo, dict *readerDict, wrapped bool) *types.Type {
+	idx := info.idx
+	var where **types.Type
+	if info.derived {
+		where = &dict.derivedTypes[idx]
+		idx = dict.derived[idx].idx
+	} else {
+		where = &pr.typs[idx]
+	}
+
+	if typ := *where; typ != nil {
+		return typ
+	}
+
+	r := pr.newReader(pkgbits.RelocType, idx, pkgbits.SyncTypeIdx)
+	r.dict = dict
+
+	typ := r.doTyp()
+	assert(typ != nil)
+
+	// For recursive type declarations involving interfaces and aliases,
+	// above r.doTyp() call may have already set pr.typs[idx], so just
+	// double check and return the type.
+	//
+	// Example:
+	//
+	//     type F = func(I)
+	//
+	//     type I interface {
+	//         m(F)
+	//     }
+	//
+	// The writer writes data types in following index order:
+	//
+	//     0: func(I)
+	//     1: I
+	//     2: interface{m(func(I))}
+	//
+	// The reader resolves it in following index order:
+	//
+	//     0 -> 1 -> 2 -> 0 -> 1
+	//
+	// and can divide in logically 2 steps:
+	//
+	//  - 0 -> 1     : first time the reader reach type I,
+	//                 it creates new named type with symbol I.
+	//
+	//  - 2 -> 0 -> 1: the reader ends up reaching symbol I again,
+	//                 now the symbol I was setup in above step, so
+	//                 the reader just return the named type.
+	//
+	// Now, the functions called return, the pr.typs looks like below:
+	//
+	//  - 0 -> 1 -> 2 -> 0 : [<T> I <T>]
+	//  - 0 -> 1 -> 2      : [func(I) I <T>]
+	//  - 0 -> 1           : [func(I) I interface { "".m(func("".I)) }]
+	//
+	// The idx 1, corresponding with type I was resolved successfully
+	// after r.doTyp() call.
+
+	if prev := *where; prev != nil {
+		return prev
+	}
+
+	if wrapped {
+		// Only cache if we're adding wrappers, so that other callers that
+		// find a cached type know it was wrapped.
+		*where = typ
+
+		r.needWrapper(typ)
+	}
+
+	if !typ.IsUntyped() {
+		types.CheckSize(typ)
+	}
+
+	return typ
+}
+
+func (r *reader) doTyp() *types.Type {
+	switch tag := pkgbits.CodeType(r.Code(pkgbits.SyncType)); tag {
+	default:
+		panic(fmt.Sprintf("unexpected type: %v", tag))
+
+	case pkgbits.TypeBasic:
+		return *basics[r.Len()]
+
+	case pkgbits.TypeNamed:
+		obj := r.obj()
+		assert(obj.Op() == ir.OTYPE)
+		return obj.Type()
+
+	case pkgbits.TypeTypeParam:
+		return r.dict.targs[r.Len()]
+
+	case pkgbits.TypeArray:
+		len := int64(r.Uint64())
+		return types.NewArray(r.typ(), len)
+	case pkgbits.TypeChan:
+		dir := dirs[r.Len()]
+		return types.NewChan(r.typ(), dir)
+	case pkgbits.TypeMap:
+		return types.NewMap(r.typ(), r.typ())
+	case pkgbits.TypePointer:
+		return types.NewPtr(r.typ())
+	case pkgbits.TypeSignature:
+		return r.signature(types.LocalPkg, nil)
+	case pkgbits.TypeSlice:
+		return types.NewSlice(r.typ())
+	case pkgbits.TypeStruct:
+		return r.structType()
+	case pkgbits.TypeInterface:
+		return r.interfaceType()
+	case pkgbits.TypeUnion:
+		return r.unionType()
+	}
+}
+
+func (r *reader) unionType() *types.Type {
+	// In the types1 universe, we only need to handle value types.
+	// Impure interfaces (i.e., interfaces with non-trivial type sets
+	// like "int | string") can only appear as type parameter bounds,
+	// and this is enforced by the types2 type checker.
+	//
+	// However, type unions can still appear in pure interfaces if the
+	// type union is equivalent to "any". E.g., typeparam/issue52124.go
+	// declares variables with the type "interface { any | int }".
+	//
+	// To avoid needing to represent type unions in types1 (since we
+	// don't have any uses for that today anyway), we simply fold them
+	// to "any". As a consistency check, we still read the union terms
+	// to make sure this substitution is safe.
+
+	pure := false
+	for i, n := 0, r.Len(); i < n; i++ {
+		_ = r.Bool() // tilde
+		term := r.typ()
+		if term.IsEmptyInterface() {
+			pure = true
+		}
+	}
+	if !pure {
+		base.Fatalf("impure type set used in value type")
+	}
+
+	return types.Types[types.TINTER]
+}
+
+func (r *reader) interfaceType() *types.Type {
+	tpkg := types.LocalPkg // TODO(mdempsky): Remove after iexport is gone.
+
+	nmethods, nembeddeds := r.Len(), r.Len()
+	implicit := nmethods == 0 && nembeddeds == 1 && r.Bool()
+	assert(!implicit) // implicit interfaces only appear in constraints
+
+	fields := make([]*types.Field, nmethods+nembeddeds)
+	methods, embeddeds := fields[:nmethods], fields[nmethods:]
+
+	for i := range methods {
+		pos := r.pos()
+		pkg, sym := r.selector()
+		tpkg = pkg
+		mtyp := r.signature(pkg, types.FakeRecv())
+		methods[i] = types.NewField(pos, sym, mtyp)
+	}
+	for i := range embeddeds {
+		embeddeds[i] = types.NewField(src.NoXPos, nil, r.typ())
+	}
+
+	if len(fields) == 0 {
+		return types.Types[types.TINTER] // empty interface
+	}
+	return types.NewInterface(tpkg, fields, false)
+}
+
+func (r *reader) structType() *types.Type {
+	tpkg := types.LocalPkg // TODO(mdempsky): Remove after iexport is gone.
+	fields := make([]*types.Field, r.Len())
+	for i := range fields {
+		pos := r.pos()
+		pkg, sym := r.selector()
+		tpkg = pkg
+		ftyp := r.typ()
+		tag := r.String()
+		embedded := r.Bool()
+
+		f := types.NewField(pos, sym, ftyp)
+		f.Note = tag
+		if embedded {
+			f.Embedded = 1
+		}
+		fields[i] = f
+	}
+	return types.NewStruct(tpkg, fields)
+}
+
+func (r *reader) signature(tpkg *types.Pkg, recv *types.Field) *types.Type {
+	r.Sync(pkgbits.SyncSignature)
+
+	params := r.params(&tpkg)
+	results := r.params(&tpkg)
+	if r.Bool() { // variadic
+		params[len(params)-1].SetIsDDD(true)
+	}
+
+	return types.NewSignature(tpkg, recv, nil, params, results)
+}
+
+func (r *reader) params(tpkg **types.Pkg) []*types.Field {
+	r.Sync(pkgbits.SyncParams)
+	fields := make([]*types.Field, r.Len())
+	for i := range fields {
+		*tpkg, fields[i] = r.param()
+	}
+	return fields
+}
+
+func (r *reader) param() (*types.Pkg, *types.Field) {
+	r.Sync(pkgbits.SyncParam)
+
+	pos := r.pos()
+	pkg, sym := r.localIdent()
+	typ := r.typ()
+
+	return pkg, types.NewField(pos, sym, typ)
+}
+
+// @@@ Objects
+
+// objReader maps qualified identifiers (represented as *types.Sym) to
+// a pkgReader and corresponding index that can be used for reading
+// that object's definition.
+var objReader = map[*types.Sym]pkgReaderIndex{}
+
+// obj reads an instantiated object reference from the bitstream.
+func (r *reader) obj() ir.Node {
+	return r.p.objInstIdx(r.objInfo(), r.dict, false)
+}
+
+// objInfo reads an instantiated object reference from the bitstream
+// and returns the encoded reference to it, without instantiating it.
+func (r *reader) objInfo() objInfo {
+	r.Sync(pkgbits.SyncObject)
+	assert(!r.Bool()) // TODO(mdempsky): Remove; was derived func inst.
+	idx := r.Reloc(pkgbits.RelocObj)
+
+	explicits := make([]typeInfo, r.Len())
+	for i := range explicits {
+		explicits[i] = r.typInfo()
+	}
+
+	return objInfo{idx, explicits}
+}
+
+// objInstIdx returns the encoded, instantiated object. If shaped is
+// true, then the shaped variant of the object is returned instead.
+func (pr *pkgReader) objInstIdx(info objInfo, dict *readerDict, shaped bool) ir.Node {
+	explicits := pr.typListIdx(info.explicits, dict)
+
+	var implicits []*types.Type
+	if dict != nil {
+		implicits = dict.targs
+	}
+
+	return pr.objIdx(info.idx, implicits, explicits, shaped)
+}
+
+// objIdx returns the specified object, instantiated with the given
+// type arguments, if any. If shaped is true, then the shaped variant
+// of the object is returned instead.
+func (pr *pkgReader) objIdx(idx pkgbits.Index, implicits, explicits []*types.Type, shaped bool) ir.Node {
+	rname := pr.newReader(pkgbits.RelocName, idx, pkgbits.SyncObject1)
+	_, sym := rname.qualifiedIdent()
+	tag := pkgbits.CodeObj(rname.Code(pkgbits.SyncCodeObj))
+
+	if tag == pkgbits.ObjStub {
+		assert(!sym.IsBlank())
+		switch sym.Pkg {
+		case types.BuiltinPkg, types.UnsafePkg:
+			return sym.Def.(ir.Node)
+		}
+		if pri, ok := objReader[sym]; ok {
+			return pri.pr.objIdx(pri.idx, nil, explicits, shaped)
+		}
+		base.Fatalf("unresolved stub: %v", sym)
+	}
+
+	dict := pr.objDictIdx(sym, idx, implicits, explicits, shaped)
+
+	sym = dict.baseSym
+	if !sym.IsBlank() && sym.Def != nil {
+		return sym.Def.(*ir.Name)
+	}
+
+	r := pr.newReader(pkgbits.RelocObj, idx, pkgbits.SyncObject1)
+	rext := pr.newReader(pkgbits.RelocObjExt, idx, pkgbits.SyncObject1)
+
+	r.dict = dict
+	rext.dict = dict
+
+	do := func(op ir.Op, hasTParams bool) *ir.Name {
+		pos := r.pos()
+		setBasePos(pos)
+		if hasTParams {
+			r.typeParamNames()
+		}
+
+		name := ir.NewDeclNameAt(pos, op, sym)
+		name.Class = ir.PEXTERN // may be overridden later
+		if !sym.IsBlank() {
+			if sym.Def != nil {
+				base.FatalfAt(name.Pos(), "already have a definition for %v", name)
+			}
+			assert(sym.Def == nil)
+			sym.Def = name
+		}
+		return name
+	}
+
+	switch tag {
+	default:
+		panic("unexpected object")
+
+	case pkgbits.ObjAlias:
+		name := do(ir.OTYPE, false)
+		setType(name, r.typ())
+		name.SetAlias(true)
+		return name
+
+	case pkgbits.ObjConst:
+		name := do(ir.OLITERAL, false)
+		typ := r.typ()
+		val := FixValue(typ, r.Value())
+		setType(name, typ)
+		setValue(name, val)
+		return name
+
+	case pkgbits.ObjFunc:
+		if sym.Name == "init" {
+			sym = Renameinit()
+		}
+		name := do(ir.ONAME, true)
+		setType(name, r.signature(sym.Pkg, nil))
+
+		name.Func = ir.NewFunc(r.pos())
+		name.Func.Nname = name
+
+		if r.hasTypeParams() {
+			name.Func.SetDupok(true)
+			if r.dict.shaped {
+				setType(name, shapeSig(name.Func, r.dict))
+			} else {
+				todoDicts = append(todoDicts, func() {
+					r.dict.shapedObj = pr.objIdx(idx, implicits, explicits, true).(*ir.Name)
+				})
+			}
+		}
+
+		rext.funcExt(name, nil)
+		return name
+
+	case pkgbits.ObjType:
+		name := do(ir.OTYPE, true)
+		typ := types.NewNamed(name)
+		setType(name, typ)
+		if r.hasTypeParams() && r.dict.shaped {
+			typ.SetHasShape(true)
+		}
+
+		// Important: We need to do this before SetUnderlying.
+		rext.typeExt(name)
+
+		// We need to defer CheckSize until we've called SetUnderlying to
+		// handle recursive types.
+		types.DeferCheckSize()
+		typ.SetUnderlying(r.typWrapped(false))
+		types.ResumeCheckSize()
+
+		if r.hasTypeParams() && !r.dict.shaped {
+			todoDicts = append(todoDicts, func() {
+				r.dict.shapedObj = pr.objIdx(idx, implicits, explicits, true).(*ir.Name)
+			})
+		}
+
+		methods := make([]*types.Field, r.Len())
+		for i := range methods {
+			methods[i] = r.method(rext)
+		}
+		if len(methods) != 0 {
+			typ.Methods().Set(methods)
+		}
+
+		if !r.dict.shaped {
+			r.needWrapper(typ)
+		}
+
+		return name
+
+	case pkgbits.ObjVar:
+		name := do(ir.ONAME, false)
+		setType(name, r.typ())
+		rext.varExt(name)
+		return name
+	}
+}
+
+func (dict *readerDict) mangle(sym *types.Sym) *types.Sym {
+	if !dict.hasTypeParams() {
+		return sym
+	}
+
+	// If sym is a locally defined generic type, we need the suffix to
+	// stay at the end after mangling so that types/fmt.go can strip it
+	// out again when writing the type's runtime descriptor (#54456).
+	base, suffix := types.SplitVargenSuffix(sym.Name)
+
+	var buf strings.Builder
+	buf.WriteString(base)
+	buf.WriteByte('[')
+	for i, targ := range dict.targs {
+		if i > 0 {
+			if i == dict.implicits {
+				buf.WriteByte(';')
+			} else {
+				buf.WriteByte(',')
+			}
+		}
+		buf.WriteString(targ.LinkString())
+	}
+	buf.WriteByte(']')
+	buf.WriteString(suffix)
+	return sym.Pkg.Lookup(buf.String())
+}
+
+// shapify returns the shape type for targ.
+//
+// If basic is true, then the type argument is used to instantiate a
+// type parameter whose constraint is a basic interface.
+func shapify(targ *types.Type, basic bool) *types.Type {
+	if targ.Kind() == types.TFORW {
+		if targ.IsFullyInstantiated() {
+			// For recursive instantiated type argument, it may  still be a TFORW
+			// when shapifying happens. If we don't have targ's underlying type,
+			// shapify won't work. The worst case is we end up not reusing code
+			// optimally in some tricky cases.
+			if base.Debug.Shapify != 0 {
+				base.Warn("skipping shaping of recursive type %v", targ)
+			}
+			if targ.HasShape() {
+				return targ
+			}
+		} else {
+			base.Fatalf("%v is missing its underlying type", targ)
+		}
+	}
+
+	// When a pointer type is used to instantiate a type parameter
+	// constrained by a basic interface, we know the pointer's element
+	// type can't matter to the generated code. In this case, we can use
+	// an arbitrary pointer type as the shape type. (To match the
+	// non-unified frontend, we use `*byte`.)
+	//
+	// Otherwise, we simply use the type's underlying type as its shape.
+	//
+	// TODO(mdempsky): It should be possible to do much more aggressive
+	// shaping still; e.g., collapsing all pointer-shaped types into a
+	// common type, collapsing scalars of the same size/alignment into a
+	// common type, recursively shaping the element types of composite
+	// types, and discarding struct field names and tags. However, we'll
+	// need to start tracking how type parameters are actually used to
+	// implement some of these optimizations.
+	under := targ.Underlying()
+	if basic && targ.IsPtr() && !targ.Elem().NotInHeap() {
+		under = types.NewPtr(types.Types[types.TUINT8])
+	}
+
+	sym := types.ShapePkg.Lookup(under.LinkString())
+	if sym.Def == nil {
+		name := ir.NewDeclNameAt(under.Pos(), ir.OTYPE, sym)
+		typ := types.NewNamed(name)
+		typ.SetUnderlying(under)
+		sym.Def = typed(typ, name)
+	}
+	res := sym.Def.Type()
+	assert(res.IsShape())
+	assert(res.HasShape())
+	return res
+}
+
+// objDictIdx reads and returns the specified object dictionary.
+func (pr *pkgReader) objDictIdx(sym *types.Sym, idx pkgbits.Index, implicits, explicits []*types.Type, shaped bool) *readerDict {
+	r := pr.newReader(pkgbits.RelocObjDict, idx, pkgbits.SyncObject1)
+
+	dict := readerDict{
+		shaped: shaped,
+	}
+
+	nimplicits := r.Len()
+	nexplicits := r.Len()
+
+	if nimplicits > len(implicits) || nexplicits != len(explicits) {
+		base.Fatalf("%v has %v+%v params, but instantiated with %v+%v args", sym, nimplicits, nexplicits, len(implicits), len(explicits))
+	}
+
+	dict.targs = append(implicits[:nimplicits:nimplicits], explicits...)
+	dict.implicits = nimplicits
+
+	// Within the compiler, we can just skip over the type parameters.
+	for range dict.targs[dict.implicits:] {
+		// Skip past bounds without actually evaluating them.
+		r.typInfo()
+	}
+
+	dict.derived = make([]derivedInfo, r.Len())
+	dict.derivedTypes = make([]*types.Type, len(dict.derived))
+	for i := range dict.derived {
+		dict.derived[i] = derivedInfo{r.Reloc(pkgbits.RelocType), r.Bool()}
+	}
+
+	// Runtime dictionary information; private to the compiler.
+
+	// If any type argument is already shaped, then we're constructing a
+	// shaped object, even if not explicitly requested (i.e., calling
+	// objIdx with shaped==true). This can happen with instantiating
+	// types that are referenced within a function body.
+	for _, targ := range dict.targs {
+		if targ.HasShape() {
+			dict.shaped = true
+			break
+		}
+	}
+
+	// And if we're constructing a shaped object, then shapify all type
+	// arguments.
+	for i, targ := range dict.targs {
+		basic := r.Bool()
+		if dict.shaped {
+			dict.targs[i] = shapify(targ, basic)
+		}
+	}
+
+	dict.baseSym = dict.mangle(sym)
+
+	dict.typeParamMethodExprs = make([]readerMethodExprInfo, r.Len())
+	for i := range dict.typeParamMethodExprs {
+		typeParamIdx := r.Len()
+		_, method := r.selector()
+
+		dict.typeParamMethodExprs[i] = readerMethodExprInfo{typeParamIdx, method}
+	}
+
+	dict.subdicts = make([]objInfo, r.Len())
+	for i := range dict.subdicts {
+		dict.subdicts[i] = r.objInfo()
+	}
+
+	dict.rtypes = make([]typeInfo, r.Len())
+	for i := range dict.rtypes {
+		dict.rtypes[i] = r.typInfo()
+	}
+
+	dict.itabs = make([]itabInfo, r.Len())
+	for i := range dict.itabs {
+		dict.itabs[i] = itabInfo{typ: r.typInfo(), iface: r.typInfo()}
+	}
+
+	return &dict
+}
+
+func (r *reader) typeParamNames() {
+	r.Sync(pkgbits.SyncTypeParamNames)
+
+	for range r.dict.targs[r.dict.implicits:] {
+		r.pos()
+		r.localIdent()
+	}
+}
+
+func (r *reader) method(rext *reader) *types.Field {
+	r.Sync(pkgbits.SyncMethod)
+	pos := r.pos()
+	pkg, sym := r.selector()
+	r.typeParamNames()
+	_, recv := r.param()
+	typ := r.signature(pkg, recv)
+
+	name := ir.NewNameAt(pos, ir.MethodSym(recv.Type, sym))
+	setType(name, typ)
+
+	name.Func = ir.NewFunc(r.pos())
+	name.Func.Nname = name
+
+	if r.hasTypeParams() {
+		name.Func.SetDupok(true)
+		if r.dict.shaped {
+			typ = shapeSig(name.Func, r.dict)
+			setType(name, typ)
+		}
+	}
+
+	rext.funcExt(name, sym)
+
+	meth := types.NewField(name.Func.Pos(), sym, typ)
+	meth.Nname = name
+	meth.SetNointerface(name.Func.Pragma&ir.Nointerface != 0)
+
+	return meth
+}
+
+func (r *reader) qualifiedIdent() (pkg *types.Pkg, sym *types.Sym) {
+	r.Sync(pkgbits.SyncSym)
+	pkg = r.pkg()
+	if name := r.String(); name != "" {
+		sym = pkg.Lookup(name)
+	}
+	return
+}
+
+func (r *reader) localIdent() (pkg *types.Pkg, sym *types.Sym) {
+	r.Sync(pkgbits.SyncLocalIdent)
+	pkg = r.pkg()
+	if name := r.String(); name != "" {
+		sym = pkg.Lookup(name)
+	}
+	return
+}
+
+func (r *reader) selector() (origPkg *types.Pkg, sym *types.Sym) {
+	r.Sync(pkgbits.SyncSelector)
+	origPkg = r.pkg()
+	name := r.String()
+	pkg := origPkg
+	if types.IsExported(name) {
+		pkg = types.LocalPkg
+	}
+	sym = pkg.Lookup(name)
+	return
+}
+
+func (r *reader) hasTypeParams() bool {
+	return r.dict.hasTypeParams()
+}
+
+func (dict *readerDict) hasTypeParams() bool {
+	return dict != nil && len(dict.targs) != 0
+}
+
+// @@@ Compiler extensions
+
+func (r *reader) funcExt(name *ir.Name, method *types.Sym) {
+	r.Sync(pkgbits.SyncFuncExt)
+
+	name.Class = 0 // so MarkFunc doesn't complain
+	ir.MarkFunc(name)
+
+	fn := name.Func
+
+	// XXX: Workaround because linker doesn't know how to copy Pos.
+	if !fn.Pos().IsKnown() {
+		fn.SetPos(name.Pos())
+	}
+
+	// Normally, we only compile local functions, which saves redundant compilation work.
+	// n.Defn is not nil for local functions, and is nil for imported function. But for
+	// generic functions, we might have an instantiation that no other package has seen before.
+	// So we need to be conservative and compile it again.
+	//
+	// That's why name.Defn is set here, so ir.VisitFuncsBottomUp can analyze function.
+	// TODO(mdempsky,cuonglm): find a cleaner way to handle this.
+	if name.Sym().Pkg == types.LocalPkg || r.hasTypeParams() {
+		name.Defn = fn
+	}
+
+	fn.Pragma = r.pragmaFlag()
+	r.linkname(name)
+
+	typecheck.Func(fn)
+
+	if r.Bool() {
+		assert(name.Defn == nil)
+
+		fn.ABI = obj.ABI(r.Uint64())
+
+		// Escape analysis.
+		for _, fs := range &types.RecvsParams {
+			for _, f := range fs(name.Type()).FieldSlice() {
+				f.Note = r.String()
+			}
+		}
+
+		if r.Bool() {
+			fn.Inl = &ir.Inline{
+				Cost:            int32(r.Len()),
+				CanDelayResults: r.Bool(),
+			}
+		}
+	} else {
+		r.addBody(name.Func, method)
+	}
+	r.Sync(pkgbits.SyncEOF)
+}
+
+func (r *reader) typeExt(name *ir.Name) {
+	r.Sync(pkgbits.SyncTypeExt)
+
+	typ := name.Type()
+
+	if r.hasTypeParams() {
+		// Set "RParams" (really type arguments here, not parameters) so
+		// this type is treated as "fully instantiated". This ensures the
+		// type descriptor is written out as DUPOK and method wrappers are
+		// generated even for imported types.
+		var targs []*types.Type
+		targs = append(targs, r.dict.targs...)
+		typ.SetRParams(targs)
+	}
+
+	name.SetPragma(r.pragmaFlag())
+
+	typecheck.SetBaseTypeIndex(typ, r.Int64(), r.Int64())
+}
+
+func (r *reader) varExt(name *ir.Name) {
+	r.Sync(pkgbits.SyncVarExt)
+	r.linkname(name)
+}
+
+func (r *reader) linkname(name *ir.Name) {
+	assert(name.Op() == ir.ONAME)
+	r.Sync(pkgbits.SyncLinkname)
+
+	if idx := r.Int64(); idx >= 0 {
+		lsym := name.Linksym()
+		lsym.SymIdx = int32(idx)
+		lsym.Set(obj.AttrIndexed, true)
+	} else {
+		name.Sym().Linkname = r.String()
+	}
+}
+
+func (r *reader) pragmaFlag() ir.PragmaFlag {
+	r.Sync(pkgbits.SyncPragma)
+	return ir.PragmaFlag(r.Int())
+}
+
+// @@@ Function bodies
+
+// bodyReader tracks where the serialized IR for a local or imported,
+// generic function's body can be found.
+var bodyReader = map[*ir.Func]pkgReaderIndex{}
+
+// importBodyReader tracks where the serialized IR for an imported,
+// static (i.e., non-generic) function body can be read.
+var importBodyReader = map[*types.Sym]pkgReaderIndex{}
+
+// bodyReaderFor returns the pkgReaderIndex for reading fn's
+// serialized IR, and whether one was found.
+func bodyReaderFor(fn *ir.Func) (pri pkgReaderIndex, ok bool) {
+	if fn.Nname.Defn != nil {
+		pri, ok = bodyReader[fn]
+		base.AssertfAt(ok, base.Pos, "must have bodyReader for %v", fn) // must always be available
+	} else {
+		pri, ok = importBodyReader[fn.Sym()]
+	}
+	return
+}
+
+// todoDicts holds the list of dictionaries that still need their
+// runtime dictionary objects constructed.
+var todoDicts []func()
+
+// todoBodies holds the list of function bodies that still need to be
+// constructed.
+var todoBodies []*ir.Func
+
+// addBody reads a function body reference from the element bitstream,
+// and associates it with fn.
+func (r *reader) addBody(fn *ir.Func, method *types.Sym) {
+	// addBody should only be called for local functions or imported
+	// generic functions; see comment in funcExt.
+	assert(fn.Nname.Defn != nil)
+
+	idx := r.Reloc(pkgbits.RelocBody)
+
+	pri := pkgReaderIndex{r.p, idx, r.dict, method, nil}
+	bodyReader[fn] = pri
+
+	if r.curfn == nil {
+		todoBodies = append(todoBodies, fn)
+		return
+	}
+
+	pri.funcBody(fn)
+}
+
+func (pri pkgReaderIndex) funcBody(fn *ir.Func) {
+	r := pri.asReader(pkgbits.RelocBody, pkgbits.SyncFuncBody)
+	r.funcBody(fn)
+}
+
+// funcBody reads a function body definition from the element
+// bitstream, and populates fn with it.
+func (r *reader) funcBody(fn *ir.Func) {
+	r.curfn = fn
+	r.closureVars = fn.ClosureVars
+	if len(r.closureVars) != 0 && r.hasTypeParams() {
+		r.dictParam = r.closureVars[len(r.closureVars)-1] // dictParam is last; see reader.funcLit
+	}
+
+	ir.WithFunc(fn, func() {
+		r.funcargs(fn)
+
+		if r.syntheticBody(fn.Pos()) {
+			return
+		}
+
+		if !r.Bool() {
+			return
+		}
+
+		body := r.stmts()
+		if body == nil {
+			body = []ir.Node{typecheck.Stmt(ir.NewBlockStmt(src.NoXPos, nil))}
+		}
+		fn.Body = body
+		fn.Endlineno = r.pos()
+	})
+
+	r.marker.WriteTo(fn)
+}
+
+// syntheticBody adds a synthetic body to r.curfn if appropriate, and
+// reports whether it did.
+func (r *reader) syntheticBody(pos src.XPos) bool {
+	if r.synthetic != nil {
+		r.synthetic(pos, r)
+		return true
+	}
+
+	// If this function has type parameters and isn't shaped, then we
+	// just tail call its corresponding shaped variant.
+	if r.hasTypeParams() && !r.dict.shaped {
+		r.callShaped(pos)
+		return true
+	}
+
+	return false
+}
+
+// callShaped emits a tail call to r.shapedFn, passing along the
+// arguments to the current function.
+func (r *reader) callShaped(pos src.XPos) {
+	shapedObj := r.dict.shapedObj
+	assert(shapedObj != nil)
+
+	var shapedFn ir.Node
+	if r.methodSym == nil {
+		// Instantiating a generic function; shapedObj is the shaped
+		// function itself.
+		assert(shapedObj.Op() == ir.ONAME && shapedObj.Class == ir.PFUNC)
+		shapedFn = shapedObj
+	} else {
+		// Instantiating a generic type's method; shapedObj is the shaped
+		// type, so we need to select it's corresponding method.
+		shapedFn = shapedMethodExpr(pos, shapedObj, r.methodSym)
+	}
+
+	recvs, params := r.syntheticArgs(pos)
+
+	// Construct the arguments list: receiver (if any), then runtime
+	// dictionary, and finally normal parameters.
+	//
+	// Note: For simplicity, shaped methods are added as normal methods
+	// on their shaped types. So existing code (e.g., packages ir and
+	// typecheck) expects the shaped type to appear as the receiver
+	// parameter (or first parameter, as a method expression). Hence
+	// putting the dictionary parameter after that is the least invasive
+	// solution at the moment.
+	var args ir.Nodes
+	args.Append(recvs...)
+	args.Append(typecheck.Expr(ir.NewAddrExpr(pos, r.p.dictNameOf(r.dict))))
+	args.Append(params...)
+
+	r.syntheticTailCall(pos, shapedFn, args)
+}
+
+// syntheticArgs returns the recvs and params arguments passed to the
+// current function.
+func (r *reader) syntheticArgs(pos src.XPos) (recvs, params ir.Nodes) {
+	sig := r.curfn.Nname.Type()
+
+	inlVarIdx := 0
+	addParams := func(out *ir.Nodes, params []*types.Field) {
+		for _, param := range params {
+			var arg ir.Node
+			if param.Nname != nil {
+				name := param.Nname.(*ir.Name)
+				if !ir.IsBlank(name) {
+					if r.inlCall != nil {
+						// During inlining, we want the respective inlvar where we
+						// assigned the callee's arguments.
+						arg = r.inlvars[inlVarIdx]
+					} else {
+						// Otherwise, we can use the parameter itself directly.
+						base.AssertfAt(name.Curfn == r.curfn, name.Pos(), "%v has curfn %v, but want %v", name, name.Curfn, r.curfn)
+						arg = name
+					}
+				}
+			}
+
+			// For anonymous and blank parameters, we don't have an *ir.Name
+			// to use as the argument. However, since we know the shaped
+			// function won't use the value either, we can just pass the
+			// zero value. (Also unfortunately, we don't have an easy
+			// zero-value IR node; so we use a default-initialized temporary
+			// variable.)
+			if arg == nil {
+				tmp := typecheck.TempAt(pos, r.curfn, param.Type)
+				r.curfn.Body.Append(
+					typecheck.Stmt(ir.NewDecl(pos, ir.ODCL, tmp)),
+					typecheck.Stmt(ir.NewAssignStmt(pos, tmp, nil)),
+				)
+				arg = tmp
+			}
+
+			out.Append(arg)
+			inlVarIdx++
+		}
+	}
+
+	addParams(&recvs, sig.Recvs().FieldSlice())
+	addParams(&params, sig.Params().FieldSlice())
+	return
+}
+
+// syntheticTailCall emits a tail call to fn, passing the given
+// arguments list.
+func (r *reader) syntheticTailCall(pos src.XPos, fn ir.Node, args ir.Nodes) {
+	// Mark the function as a wrapper so it doesn't show up in stack
+	// traces.
+	r.curfn.SetWrapper(true)
+
+	call := typecheck.Call(pos, fn, args, fn.Type().IsVariadic()).(*ir.CallExpr)
+
+	var stmt ir.Node
+	if fn.Type().NumResults() != 0 {
+		stmt = typecheck.Stmt(ir.NewReturnStmt(pos, []ir.Node{call}))
+	} else {
+		stmt = call
+	}
+	r.curfn.Body.Append(stmt)
+}
+
+// dictNameOf returns the runtime dictionary corresponding to dict.
+func (pr *pkgReader) dictNameOf(dict *readerDict) *ir.Name {
+	pos := base.AutogeneratedPos
+
+	// Check that we only instantiate runtime dictionaries with real types.
+	base.AssertfAt(!dict.shaped, pos, "runtime dictionary of shaped object %v", dict.baseSym)
+
+	sym := dict.baseSym.Pkg.Lookup(objabi.GlobalDictPrefix + "." + dict.baseSym.Name)
+	if sym.Def != nil {
+		return sym.Def.(*ir.Name)
+	}
+
+	name := ir.NewNameAt(pos, sym)
+	name.Class = ir.PEXTERN
+	sym.Def = name // break cycles with mutual subdictionaries
+
+	lsym := name.Linksym()
+	ot := 0
+
+	assertOffset := func(section string, offset int) {
+		base.AssertfAt(ot == offset*types.PtrSize, pos, "writing section %v at offset %v, but it should be at %v*%v", section, ot, offset, types.PtrSize)
+	}
+
+	assertOffset("type param method exprs", dict.typeParamMethodExprsOffset())
+	for _, info := range dict.typeParamMethodExprs {
+		typeParam := dict.targs[info.typeParamIdx]
+		method := typecheck.Expr(ir.NewSelectorExpr(pos, ir.OXDOT, ir.TypeNode(typeParam), info.method)).(*ir.SelectorExpr)
+		assert(method.Op() == ir.OMETHEXPR)
+
+		rsym := method.FuncName().Linksym()
+		assert(rsym.ABI() == obj.ABIInternal) // must be ABIInternal; see ir.OCFUNC in ssagen/ssa.go
+
+		ot = objw.SymPtr(lsym, ot, rsym, 0)
+	}
+
+	assertOffset("subdictionaries", dict.subdictsOffset())
+	for _, info := range dict.subdicts {
+		explicits := pr.typListIdx(info.explicits, dict)
+
+		// Careful: Due to subdictionary cycles, name may not be fully
+		// initialized yet.
+		name := pr.objDictName(info.idx, dict.targs, explicits)
+
+		ot = objw.SymPtr(lsym, ot, name.Linksym(), 0)
+	}
+
+	assertOffset("rtypes", dict.rtypesOffset())
+	for _, info := range dict.rtypes {
+		typ := pr.typIdx(info, dict, true)
+		ot = objw.SymPtr(lsym, ot, reflectdata.TypeLinksym(typ), 0)
+
+		// TODO(mdempsky): Double check this.
+		reflectdata.MarkTypeUsedInInterface(typ, lsym)
+	}
+
+	// For each (typ, iface) pair, we write the *runtime.itab pointer
+	// for the pair. For pairs that don't actually require an itab
+	// (i.e., typ is an interface, or iface is an empty interface), we
+	// write a nil pointer instead. This is wasteful, but rare in
+	// practice (e.g., instantiating a type parameter with an interface
+	// type).
+	assertOffset("itabs", dict.itabsOffset())
+	for _, info := range dict.itabs {
+		typ := pr.typIdx(info.typ, dict, true)
+		iface := pr.typIdx(info.iface, dict, true)
+
+		if !typ.IsInterface() && iface.IsInterface() && !iface.IsEmptyInterface() {
+			ot = objw.SymPtr(lsym, ot, reflectdata.ITabLsym(typ, iface), 0)
+		} else {
+			ot += types.PtrSize
+		}
+
+		// TODO(mdempsky): Double check this.
+		reflectdata.MarkTypeUsedInInterface(typ, lsym)
+		reflectdata.MarkTypeUsedInInterface(iface, lsym)
+	}
+
+	objw.Global(lsym, int32(ot), obj.DUPOK|obj.RODATA)
+
+	name.SetType(dict.varType())
+	name.SetTypecheck(1)
+
+	return name
+}
+
+// typeParamMethodExprsOffset returns the offset of the runtime
+// dictionary's type parameter method expressions section, in words.
+func (dict *readerDict) typeParamMethodExprsOffset() int {
+	return 0
+}
+
+// subdictsOffset returns the offset of the runtime dictionary's
+// subdictionary section, in words.
+func (dict *readerDict) subdictsOffset() int {
+	return dict.typeParamMethodExprsOffset() + len(dict.typeParamMethodExprs)
+}
+
+// rtypesOffset returns the offset of the runtime dictionary's rtypes
+// section, in words.
+func (dict *readerDict) rtypesOffset() int {
+	return dict.subdictsOffset() + len(dict.subdicts)
+}
+
+// itabsOffset returns the offset of the runtime dictionary's itabs
+// section, in words.
+func (dict *readerDict) itabsOffset() int {
+	return dict.rtypesOffset() + len(dict.rtypes)
+}
+
+// numWords returns the total number of words that comprise dict's
+// runtime dictionary variable.
+func (dict *readerDict) numWords() int64 {
+	return int64(dict.itabsOffset() + len(dict.itabs))
+}
+
+// varType returns the type of dict's runtime dictionary variable.
+func (dict *readerDict) varType() *types.Type {
+	return types.NewArray(types.Types[types.TUINTPTR], dict.numWords())
+}
+
+func (r *reader) funcargs(fn *ir.Func) {
+	sig := fn.Nname.Type()
+
+	if recv := sig.Recv(); recv != nil {
+		r.funcarg(recv, recv.Sym, ir.PPARAM)
+	}
+	for _, param := range sig.Params().FieldSlice() {
+		r.funcarg(param, param.Sym, ir.PPARAM)
+	}
+
+	for i, param := range sig.Results().FieldSlice() {
+		sym := types.OrigSym(param.Sym)
+
+		if sym == nil || sym.IsBlank() {
+			prefix := "~r"
+			if r.inlCall != nil {
+				prefix = "~R"
+			} else if sym != nil {
+				prefix = "~b"
+			}
+			sym = typecheck.LookupNum(prefix, i)
+		}
+
+		r.funcarg(param, sym, ir.PPARAMOUT)
+	}
+}
+
+func (r *reader) funcarg(param *types.Field, sym *types.Sym, ctxt ir.Class) {
+	if sym == nil {
+		assert(ctxt == ir.PPARAM)
+		if r.inlCall != nil {
+			r.inlvars.Append(ir.BlankNode)
+		}
+		return
+	}
+
+	name := ir.NewNameAt(r.inlPos(param.Pos), sym)
+	setType(name, param.Type)
+	r.addLocal(name, ctxt)
+
+	if r.inlCall == nil {
+		if !r.funarghack {
+			param.Sym = sym
+			param.Nname = name
+		}
+	} else {
+		if ctxt == ir.PPARAMOUT {
+			r.retvars.Append(name)
+		} else {
+			r.inlvars.Append(name)
+		}
+	}
+}
+
+func (r *reader) addLocal(name *ir.Name, ctxt ir.Class) {
+	assert(ctxt == ir.PAUTO || ctxt == ir.PPARAM || ctxt == ir.PPARAMOUT)
+
+	if name.Sym().Name == dictParamName {
+		r.dictParam = name
+	} else {
+		if r.synthetic == nil {
+			r.Sync(pkgbits.SyncAddLocal)
+			if r.p.SyncMarkers() {
+				want := r.Int()
+				if have := len(r.locals); have != want {
+					base.FatalfAt(name.Pos(), "locals table has desynced")
+				}
+			}
+			r.varDictIndex(name)
+		}
+
+		r.locals = append(r.locals, name)
+	}
+
+	name.SetUsed(true)
+
+	// TODO(mdempsky): Move earlier.
+	if ir.IsBlank(name) {
+		return
+	}
+
+	if r.inlCall != nil {
+		if ctxt == ir.PAUTO {
+			name.SetInlLocal(true)
+		} else {
+			name.SetInlFormal(true)
+			ctxt = ir.PAUTO
+		}
+
+		// TODO(mdempsky): Rethink this hack.
+		if strings.HasPrefix(name.Sym().Name, "~") || base.Flag.GenDwarfInl == 0 {
+			name.SetPos(r.inlCall.Pos())
+			name.SetInlFormal(false)
+			name.SetInlLocal(false)
+		}
+	}
+
+	name.Class = ctxt
+	name.Curfn = r.curfn
+
+	r.curfn.Dcl = append(r.curfn.Dcl, name)
+
+	if ctxt == ir.PAUTO {
+		name.SetFrameOffset(0)
+	}
+}
+
+func (r *reader) useLocal() *ir.Name {
+	r.Sync(pkgbits.SyncUseObjLocal)
+	if r.Bool() {
+		return r.locals[r.Len()]
+	}
+	return r.closureVars[r.Len()]
+}
+
+func (r *reader) openScope() {
+	r.Sync(pkgbits.SyncOpenScope)
+	pos := r.pos()
+
+	if base.Flag.Dwarf {
+		r.scopeVars = append(r.scopeVars, len(r.curfn.Dcl))
+		r.marker.Push(pos)
+	}
+}
+
+func (r *reader) closeScope() {
+	r.Sync(pkgbits.SyncCloseScope)
+	r.lastCloseScopePos = r.pos()
+
+	r.closeAnotherScope()
+}
+
+// closeAnotherScope is like closeScope, but it reuses the same mark
+// position as the last closeScope call. This is useful for "for" and
+// "if" statements, as their implicit blocks always end at the same
+// position as an explicit block.
+func (r *reader) closeAnotherScope() {
+	r.Sync(pkgbits.SyncCloseAnotherScope)
+
+	if base.Flag.Dwarf {
+		scopeVars := r.scopeVars[len(r.scopeVars)-1]
+		r.scopeVars = r.scopeVars[:len(r.scopeVars)-1]
+
+		// Quirkish: noder decides which scopes to keep before
+		// typechecking, whereas incremental typechecking during IR
+		// construction can result in new autotemps being allocated. To
+		// produce identical output, we ignore autotemps here for the
+		// purpose of deciding whether to retract the scope.
+		//
+		// This is important for net/http/fcgi, because it contains:
+		//
+		//	var body io.ReadCloser
+		//	if len(content) > 0 {
+		//		body, req.pw = io.Pipe()
+		//	} else { … }
+		//
+		// Notably, io.Pipe is inlinable, and inlining it introduces a ~R0
+		// variable at the call site.
+		//
+		// Noder does not preserve the scope where the io.Pipe() call
+		// resides, because it doesn't contain any declared variables in
+		// source. So the ~R0 variable ends up being assigned to the
+		// enclosing scope instead.
+		//
+		// However, typechecking this assignment also introduces
+		// autotemps, because io.Pipe's results need conversion before
+		// they can be assigned to their respective destination variables.
+		//
+		// TODO(mdempsky): We should probably just keep all scopes, and
+		// let dwarfgen take care of pruning them instead.
+		retract := true
+		for _, n := range r.curfn.Dcl[scopeVars:] {
+			if !n.AutoTemp() {
+				retract = false
+				break
+			}
+		}
+
+		if retract {
+			// no variables were declared in this scope, so we can retract it.
+			r.marker.Unpush()
+		} else {
+			r.marker.Pop(r.lastCloseScopePos)
+		}
+	}
+}
+
+// @@@ Statements
+
+func (r *reader) stmt() ir.Node {
+	switch stmts := r.stmts(); len(stmts) {
+	case 0:
+		return nil
+	case 1:
+		return stmts[0]
+	default:
+		return ir.NewBlockStmt(stmts[0].Pos(), stmts)
+	}
+}
+
+func (r *reader) stmts() []ir.Node {
+	assert(ir.CurFunc == r.curfn)
+	var res ir.Nodes
+
+	r.Sync(pkgbits.SyncStmts)
+	for {
+		tag := codeStmt(r.Code(pkgbits.SyncStmt1))
+		if tag == stmtEnd {
+			r.Sync(pkgbits.SyncStmtsEnd)
+			return res
+		}
+
+		if n := r.stmt1(tag, &res); n != nil {
+			res.Append(typecheck.Stmt(n))
+		}
+	}
+}
+
+func (r *reader) stmt1(tag codeStmt, out *ir.Nodes) ir.Node {
+	var label *types.Sym
+	if n := len(*out); n > 0 {
+		if ls, ok := (*out)[n-1].(*ir.LabelStmt); ok {
+			label = ls.Label
+		}
+	}
+
+	switch tag {
+	default:
+		panic("unexpected statement")
+
+	case stmtAssign:
+		pos := r.pos()
+		names, lhs := r.assignList()
+		rhs := r.multiExpr()
+
+		if len(rhs) == 0 {
+			for _, name := range names {
+				as := ir.NewAssignStmt(pos, name, nil)
+				as.PtrInit().Append(ir.NewDecl(pos, ir.ODCL, name))
+				out.Append(typecheck.Stmt(as))
+			}
+			return nil
+		}
+
+		if len(lhs) == 1 && len(rhs) == 1 {
+			n := ir.NewAssignStmt(pos, lhs[0], rhs[0])
+			n.Def = r.initDefn(n, names)
+			return n
+		}
+
+		n := ir.NewAssignListStmt(pos, ir.OAS2, lhs, rhs)
+		n.Def = r.initDefn(n, names)
+		return n
+
+	case stmtAssignOp:
+		op := r.op()
+		lhs := r.expr()
+		pos := r.pos()
+		rhs := r.expr()
+		return ir.NewAssignOpStmt(pos, op, lhs, rhs)
+
+	case stmtIncDec:
+		op := r.op()
+		lhs := r.expr()
+		pos := r.pos()
+		n := ir.NewAssignOpStmt(pos, op, lhs, ir.NewBasicLit(pos, one))
+		n.IncDec = true
+		return n
+
+	case stmtBlock:
+		out.Append(r.blockStmt()...)
+		return nil
+
+	case stmtBranch:
+		pos := r.pos()
+		op := r.op()
+		sym := r.optLabel()
+		return ir.NewBranchStmt(pos, op, sym)
+
+	case stmtCall:
+		pos := r.pos()
+		op := r.op()
+		call := r.expr()
+		return ir.NewGoDeferStmt(pos, op, call)
+
+	case stmtExpr:
+		return r.expr()
+
+	case stmtFor:
+		return r.forStmt(label)
+
+	case stmtIf:
+		return r.ifStmt()
+
+	case stmtLabel:
+		pos := r.pos()
+		sym := r.label()
+		return ir.NewLabelStmt(pos, sym)
+
+	case stmtReturn:
+		pos := r.pos()
+		results := r.multiExpr()
+		return ir.NewReturnStmt(pos, results)
+
+	case stmtSelect:
+		return r.selectStmt(label)
+
+	case stmtSend:
+		pos := r.pos()
+		ch := r.expr()
+		value := r.expr()
+		return ir.NewSendStmt(pos, ch, value)
+
+	case stmtSwitch:
+		return r.switchStmt(label)
+	}
+}
+
+func (r *reader) assignList() ([]*ir.Name, []ir.Node) {
+	lhs := make([]ir.Node, r.Len())
+	var names []*ir.Name
+
+	for i := range lhs {
+		expr, def := r.assign()
+		lhs[i] = expr
+		if def {
+			names = append(names, expr.(*ir.Name))
+		}
+	}
+
+	return names, lhs
+}
+
+// assign returns an assignee expression. It also reports whether the
+// returned expression is a newly declared variable.
+func (r *reader) assign() (ir.Node, bool) {
+	switch tag := codeAssign(r.Code(pkgbits.SyncAssign)); tag {
+	default:
+		panic("unhandled assignee expression")
+
+	case assignBlank:
+		return typecheck.AssignExpr(ir.BlankNode), false
+
+	case assignDef:
+		pos := r.pos()
+		setBasePos(pos)
+		_, sym := r.localIdent()
+		typ := r.typ()
+
+		name := ir.NewNameAt(pos, sym)
+		setType(name, typ)
+		r.addLocal(name, ir.PAUTO)
+		return name, true
+
+	case assignExpr:
+		return r.expr(), false
+	}
+}
+
+func (r *reader) blockStmt() []ir.Node {
+	r.Sync(pkgbits.SyncBlockStmt)
+	r.openScope()
+	stmts := r.stmts()
+	r.closeScope()
+	return stmts
+}
+
+func (r *reader) forStmt(label *types.Sym) ir.Node {
+	r.Sync(pkgbits.SyncForStmt)
+
+	r.openScope()
+
+	if r.Bool() {
+		pos := r.pos()
+		rang := ir.NewRangeStmt(pos, nil, nil, nil, nil)
+		rang.Label = label
+
+		names, lhs := r.assignList()
+		if len(lhs) >= 1 {
+			rang.Key = lhs[0]
+			if len(lhs) >= 2 {
+				rang.Value = lhs[1]
+			}
+		}
+		rang.Def = r.initDefn(rang, names)
+
+		rang.X = r.expr()
+		if rang.X.Type().IsMap() {
+			rang.RType = r.rtype(pos)
+		}
+		if rang.Key != nil && !ir.IsBlank(rang.Key) {
+			rang.KeyTypeWord, rang.KeySrcRType = r.convRTTI(pos)
+		}
+		if rang.Value != nil && !ir.IsBlank(rang.Value) {
+			rang.ValueTypeWord, rang.ValueSrcRType = r.convRTTI(pos)
+		}
+
+		rang.Body = r.blockStmt()
+		r.closeAnotherScope()
+
+		return rang
+	}
+
+	pos := r.pos()
+	init := r.stmt()
+	cond := r.optExpr()
+	post := r.stmt()
+	body := r.blockStmt()
+	r.closeAnotherScope()
+
+	stmt := ir.NewForStmt(pos, init, cond, post, body)
+	stmt.Label = label
+	return stmt
+}
+
+func (r *reader) ifStmt() ir.Node {
+	r.Sync(pkgbits.SyncIfStmt)
+	r.openScope()
+	pos := r.pos()
+	init := r.stmts()
+	cond := r.expr()
+	then := r.blockStmt()
+	els := r.stmts()
+	n := ir.NewIfStmt(pos, cond, then, els)
+	n.SetInit(init)
+	r.closeAnotherScope()
+	return n
+}
+
+func (r *reader) selectStmt(label *types.Sym) ir.Node {
+	r.Sync(pkgbits.SyncSelectStmt)
+
+	pos := r.pos()
+	clauses := make([]*ir.CommClause, r.Len())
+	for i := range clauses {
+		if i > 0 {
+			r.closeScope()
+		}
+		r.openScope()
+
+		pos := r.pos()
+		comm := r.stmt()
+		body := r.stmts()
+
+		// "case i = <-c: ..." may require an implicit conversion (e.g.,
+		// see fixedbugs/bug312.go). Currently, typecheck throws away the
+		// implicit conversion and relies on it being reinserted later,
+		// but that would lose any explicit RTTI operands too. To preserve
+		// RTTI, we rewrite this as "case tmp := <-c: i = tmp; ...".
+		if as, ok := comm.(*ir.AssignStmt); ok && as.Op() == ir.OAS && !as.Def {
+			if conv, ok := as.Y.(*ir.ConvExpr); ok && conv.Op() == ir.OCONVIFACE {
+				base.AssertfAt(conv.Implicit(), conv.Pos(), "expected implicit conversion: %v", conv)
+
+				recv := conv.X
+				base.AssertfAt(recv.Op() == ir.ORECV, recv.Pos(), "expected receive expression: %v", recv)
+
+				tmp := r.temp(pos, recv.Type())
+
+				// Replace comm with `tmp := <-c`.
+				tmpAs := ir.NewAssignStmt(pos, tmp, recv)
+				tmpAs.Def = true
+				tmpAs.PtrInit().Append(ir.NewDecl(pos, ir.ODCL, tmp))
+				comm = tmpAs
+
+				// Change original assignment to `i = tmp`, and prepend to body.
+				conv.X = tmp
+				body = append([]ir.Node{as}, body...)
+			}
+		}
+
+		// multiExpr will have desugared a comma-ok receive expression
+		// into a separate statement. However, the rest of the compiler
+		// expects comm to be the OAS2RECV statement itself, so we need to
+		// shuffle things around to fit that pattern.
+		if as2, ok := comm.(*ir.AssignListStmt); ok && as2.Op() == ir.OAS2 {
+			init := ir.TakeInit(as2.Rhs[0])
+			base.AssertfAt(len(init) == 1 && init[0].Op() == ir.OAS2RECV, as2.Pos(), "unexpected assignment: %+v", as2)
+
+			comm = init[0]
+			body = append([]ir.Node{as2}, body...)
+		}
+
+		clauses[i] = ir.NewCommStmt(pos, comm, body)
+	}
+	if len(clauses) > 0 {
+		r.closeScope()
+	}
+	n := ir.NewSelectStmt(pos, clauses)
+	n.Label = label
+	return n
+}
+
+func (r *reader) switchStmt(label *types.Sym) ir.Node {
+	r.Sync(pkgbits.SyncSwitchStmt)
+
+	r.openScope()
+	pos := r.pos()
+	init := r.stmt()
+
+	var tag ir.Node
+	var ident *ir.Ident
+	var iface *types.Type
+	if r.Bool() {
+		pos := r.pos()
+		if r.Bool() {
+			pos := r.pos()
+			_, sym := r.localIdent()
+			ident = ir.NewIdent(pos, sym)
+		}
+		x := r.expr()
+		iface = x.Type()
+		tag = ir.NewTypeSwitchGuard(pos, ident, x)
+	} else {
+		tag = r.optExpr()
+	}
+
+	clauses := make([]*ir.CaseClause, r.Len())
+	for i := range clauses {
+		if i > 0 {
+			r.closeScope()
+		}
+		r.openScope()
+
+		pos := r.pos()
+		var cases, rtypes []ir.Node
+		if iface != nil {
+			cases = make([]ir.Node, r.Len())
+			if len(cases) == 0 {
+				cases = nil // TODO(mdempsky): Unclear if this matters.
+			}
+			for i := range cases {
+				if r.Bool() { // case nil
+					cases[i] = typecheck.Expr(types.BuiltinPkg.Lookup("nil").Def.(*ir.NilExpr))
+				} else {
+					cases[i] = r.exprType()
+				}
+			}
+		} else {
+			cases = r.exprList()
+
+			// For `switch { case any(true): }` (e.g., issue 3980 in
+			// test/switch.go), the backend still creates a mixed bool/any
+			// comparison, and we need to explicitly supply the RTTI for the
+			// comparison.
+			//
+			// TODO(mdempsky): Change writer.go to desugar "switch {" into
+			// "switch true {", which we already handle correctly.
+			if tag == nil {
+				for i, cas := range cases {
+					if cas.Type().IsEmptyInterface() {
+						for len(rtypes) < i {
+							rtypes = append(rtypes, nil)
+						}
+						rtypes = append(rtypes, reflectdata.TypePtrAt(cas.Pos(), types.Types[types.TBOOL]))
+					}
+				}
+			}
+		}
+
+		clause := ir.NewCaseStmt(pos, cases, nil)
+		clause.RTypes = rtypes
+
+		if ident != nil {
+			pos := r.pos()
+			typ := r.typ()
+
+			name := ir.NewNameAt(pos, ident.Sym())
+			setType(name, typ)
+			r.addLocal(name, ir.PAUTO)
+			clause.Var = name
+			name.Defn = tag
+		}
+
+		clause.Body = r.stmts()
+		clauses[i] = clause
+	}
+	if len(clauses) > 0 {
+		r.closeScope()
+	}
+	r.closeScope()
+
+	n := ir.NewSwitchStmt(pos, tag, clauses)
+	n.Label = label
+	if init != nil {
+		n.SetInit([]ir.Node{init})
+	}
+	return n
+}
+
+func (r *reader) label() *types.Sym {
+	r.Sync(pkgbits.SyncLabel)
+	name := r.String()
+	if r.inlCall != nil {
+		name = fmt.Sprintf("~%s·%d", name, inlgen)
+	}
+	return typecheck.Lookup(name)
+}
+
+func (r *reader) optLabel() *types.Sym {
+	r.Sync(pkgbits.SyncOptLabel)
+	if r.Bool() {
+		return r.label()
+	}
+	return nil
+}
+
+// initDefn marks the given names as declared by defn and populates
+// its Init field with ODCL nodes. It then reports whether any names
+// were so declared, which can be used to initialize defn.Def.
+func (r *reader) initDefn(defn ir.InitNode, names []*ir.Name) bool {
+	if len(names) == 0 {
+		return false
+	}
+
+	init := make([]ir.Node, len(names))
+	for i, name := range names {
+		name.Defn = defn
+		init[i] = ir.NewDecl(name.Pos(), ir.ODCL, name)
+	}
+	defn.SetInit(init)
+	return true
+}
+
+// @@@ Expressions
+
+// expr reads and returns a typechecked expression.
+func (r *reader) expr() (res ir.Node) {
+	defer func() {
+		if res != nil && res.Typecheck() == 0 {
+			base.FatalfAt(res.Pos(), "%v missed typecheck", res)
+		}
+	}()
+
+	switch tag := codeExpr(r.Code(pkgbits.SyncExpr)); tag {
+	default:
+		panic("unhandled expression")
+
+	case exprLocal:
+		return typecheck.Expr(r.useLocal())
+
+	case exprGlobal:
+		// Callee instead of Expr allows builtins
+		// TODO(mdempsky): Handle builtins directly in exprCall, like method calls?
+		return typecheck.Callee(r.obj())
+
+	case exprFuncInst:
+		origPos, pos := r.origPos()
+		wrapperFn, baseFn, dictPtr := r.funcInst(pos)
+		if wrapperFn != nil {
+			return wrapperFn
+		}
+		return r.curry(origPos, false, baseFn, dictPtr, nil)
+
+	case exprConst:
+		pos := r.pos()
+		typ := r.typ()
+		val := FixValue(typ, r.Value())
+		op := r.op()
+		orig := r.String()
+		return typecheck.Expr(OrigConst(pos, typ, val, op, orig))
+
+	case exprNil:
+		pos := r.pos()
+		typ := r.typ()
+		return Nil(pos, typ)
+
+	case exprCompLit:
+		return r.compLit()
+
+	case exprFuncLit:
+		return r.funcLit()
+
+	case exprFieldVal:
+		x := r.expr()
+		pos := r.pos()
+		_, sym := r.selector()
+
+		return typecheck.Expr(ir.NewSelectorExpr(pos, ir.OXDOT, x, sym)).(*ir.SelectorExpr)
+
+	case exprMethodVal:
+		recv := r.expr()
+		origPos, pos := r.origPos()
+		wrapperFn, baseFn, dictPtr := r.methodExpr()
+
+		// For simple wrapperFn values, the existing machinery for creating
+		// and deduplicating wrapperFn value wrappers still works fine.
+		if wrapperFn, ok := wrapperFn.(*ir.SelectorExpr); ok && wrapperFn.Op() == ir.OMETHEXPR {
+			// The receiver expression we constructed may have a shape type.
+			// For example, in fixedbugs/issue54343.go, `New[int]()` is
+			// constructed as `New[go.shape.int](&.dict.New[int])`, which
+			// has type `*T[go.shape.int]`, not `*T[int]`.
+			//
+			// However, the method we want to select here is `(*T[int]).M`,
+			// not `(*T[go.shape.int]).M`, so we need to manually convert
+			// the type back so that the OXDOT resolves correctly.
+			//
+			// TODO(mdempsky): Logically it might make more sense for
+			// exprCall to take responsibility for setting a non-shaped
+			// result type, but this is the only place where we care
+			// currently. And only because existing ir.OMETHVALUE backend
+			// code relies on n.X.Type() instead of n.Selection.Recv().Type
+			// (because the latter is types.FakeRecvType() in the case of
+			// interface method values).
+			//
+			if recv.Type().HasShape() {
+				typ := wrapperFn.Type().Params().Field(0).Type
+				if !types.Identical(typ, recv.Type()) {
+					base.FatalfAt(wrapperFn.Pos(), "receiver %L does not match %L", recv, wrapperFn)
+				}
+				recv = typecheck.Expr(ir.NewConvExpr(recv.Pos(), ir.OCONVNOP, typ, recv))
+			}
+
+			n := typecheck.Expr(ir.NewSelectorExpr(pos, ir.OXDOT, recv, wrapperFn.Sel)).(*ir.SelectorExpr)
+
+			// As a consistency check here, we make sure "n" selected the
+			// same method (represented by a types.Field) that wrapperFn
+			// selected. However, for anonymous receiver types, there can be
+			// multiple such types.Field instances (#58563). So we may need
+			// to fallback to making sure Sym and Type (including the
+			// receiver parameter's type) match.
+			if n.Selection != wrapperFn.Selection {
+				assert(n.Selection.Sym == wrapperFn.Selection.Sym)
+				assert(types.Identical(n.Selection.Type, wrapperFn.Selection.Type))
+				assert(types.Identical(n.Selection.Type.Recv().Type, wrapperFn.Selection.Type.Recv().Type))
+			}
+
+			wrapper := methodValueWrapper{
+				rcvr:   n.X.Type(),
+				method: n.Selection,
+			}
+
+			if r.importedDef() {
+				haveMethodValueWrappers = append(haveMethodValueWrappers, wrapper)
+			} else {
+				needMethodValueWrappers = append(needMethodValueWrappers, wrapper)
+			}
+			return n
+		}
+
+		// For more complicated method expressions, we construct a
+		// function literal wrapper.
+		return r.curry(origPos, true, baseFn, recv, dictPtr)
+
+	case exprMethodExpr:
+		recv := r.typ()
+
+		implicits := make([]int, r.Len())
+		for i := range implicits {
+			implicits[i] = r.Len()
+		}
+		var deref, addr bool
+		if r.Bool() {
+			deref = true
+		} else if r.Bool() {
+			addr = true
+		}
+
+		origPos, pos := r.origPos()
+		wrapperFn, baseFn, dictPtr := r.methodExpr()
+
+		// If we already have a wrapper and don't need to do anything with
+		// it, we can just return the wrapper directly.
+		//
+		// N.B., we use implicits/deref/addr here as the source of truth
+		// rather than types.Identical, because the latter can be confused
+		// by tricky promoted methods (e.g., typeparam/mdempsky/21.go).
+		if wrapperFn != nil && len(implicits) == 0 && !deref && !addr {
+			if !types.Identical(recv, wrapperFn.Type().Params().Field(0).Type) {
+				base.FatalfAt(pos, "want receiver type %v, but have method %L", recv, wrapperFn)
+			}
+			return wrapperFn
+		}
+
+		// Otherwise, if the wrapper function is a static method
+		// expression (OMETHEXPR) and the receiver type is unshaped, then
+		// we can rely on a statically generated wrapper being available.
+		if method, ok := wrapperFn.(*ir.SelectorExpr); ok && method.Op() == ir.OMETHEXPR && !recv.HasShape() {
+			return typecheck.Expr(ir.NewSelectorExpr(pos, ir.OXDOT, ir.TypeNode(recv), method.Sel)).(*ir.SelectorExpr)
+		}
+
+		return r.methodExprWrap(origPos, recv, implicits, deref, addr, baseFn, dictPtr)
+
+	case exprIndex:
+		x := r.expr()
+		pos := r.pos()
+		index := r.expr()
+		n := typecheck.Expr(ir.NewIndexExpr(pos, x, index))
+		switch n.Op() {
+		case ir.OINDEXMAP:
+			n := n.(*ir.IndexExpr)
+			n.RType = r.rtype(pos)
+		}
+		return n
+
+	case exprSlice:
+		x := r.expr()
+		pos := r.pos()
+		var index [3]ir.Node
+		for i := range index {
+			index[i] = r.optExpr()
+		}
+		op := ir.OSLICE
+		if index[2] != nil {
+			op = ir.OSLICE3
+		}
+		return typecheck.Expr(ir.NewSliceExpr(pos, op, x, index[0], index[1], index[2]))
+
+	case exprAssert:
+		x := r.expr()
+		pos := r.pos()
+		typ := r.exprType()
+		srcRType := r.rtype(pos)
+
+		// TODO(mdempsky): Always emit ODYNAMICDOTTYPE for uniformity?
+		if typ, ok := typ.(*ir.DynamicType); ok && typ.Op() == ir.ODYNAMICTYPE {
+			assert := ir.NewDynamicTypeAssertExpr(pos, ir.ODYNAMICDOTTYPE, x, typ.RType)
+			assert.SrcRType = srcRType
+			assert.ITab = typ.ITab
+			return typed(typ.Type(), assert)
+		}
+		return typecheck.Expr(ir.NewTypeAssertExpr(pos, x, typ.Type()))
+
+	case exprUnaryOp:
+		op := r.op()
+		pos := r.pos()
+		x := r.expr()
+
+		switch op {
+		case ir.OADDR:
+			return typecheck.Expr(typecheck.NodAddrAt(pos, x))
+		case ir.ODEREF:
+			return typecheck.Expr(ir.NewStarExpr(pos, x))
+		}
+		return typecheck.Expr(ir.NewUnaryExpr(pos, op, x))
+
+	case exprBinaryOp:
+		op := r.op()
+		x := r.expr()
+		pos := r.pos()
+		y := r.expr()
+
+		switch op {
+		case ir.OANDAND, ir.OOROR:
+			return typecheck.Expr(ir.NewLogicalExpr(pos, op, x, y))
+		}
+		return typecheck.Expr(ir.NewBinaryExpr(pos, op, x, y))
+
+	case exprRecv:
+		x := r.expr()
+		pos := r.pos()
+		for i, n := 0, r.Len(); i < n; i++ {
+			x = Implicit(DotField(pos, x, r.Len()))
+		}
+		if r.Bool() { // needs deref
+			x = Implicit(Deref(pos, x.Type().Elem(), x))
+		} else if r.Bool() { // needs addr
+			x = Implicit(Addr(pos, x))
+		}
+		return x
+
+	case exprCall:
+		var fun ir.Node
+		var args ir.Nodes
+		if r.Bool() { // method call
+			recv := r.expr()
+			_, method, dictPtr := r.methodExpr()
+
+			if recv.Type().IsInterface() && method.Op() == ir.OMETHEXPR {
+				method := method.(*ir.SelectorExpr)
+
+				// The compiler backend (e.g., devirtualization) handle
+				// OCALLINTER/ODOTINTER better than OCALLFUNC/OMETHEXPR for
+				// interface calls, so we prefer to continue constructing
+				// calls that way where possible.
+				//
+				// There are also corner cases where semantically it's perhaps
+				// significant; e.g., fixedbugs/issue15975.go, #38634, #52025.
+
+				fun = typecheck.Callee(ir.NewSelectorExpr(method.Pos(), ir.OXDOT, recv, method.Sel))
+			} else {
+				if recv.Type().IsInterface() {
+					// N.B., this happens currently for typeparam/issue51521.go
+					// and typeparam/typeswitch3.go.
+					if base.Flag.LowerM > 0 {
+						base.WarnfAt(method.Pos(), "imprecise interface call")
+					}
+				}
+
+				fun = method
+				args.Append(recv)
+			}
+			if dictPtr != nil {
+				args.Append(dictPtr)
+			}
+		} else if r.Bool() { // call to instanced function
+			pos := r.pos()
+			_, shapedFn, dictPtr := r.funcInst(pos)
+			fun = shapedFn
+			args.Append(dictPtr)
+		} else {
+			fun = r.expr()
+		}
+		pos := r.pos()
+		args.Append(r.multiExpr()...)
+		dots := r.Bool()
+		n := typecheck.Call(pos, fun, args, dots)
+		switch n.Op() {
+		case ir.OAPPEND:
+			n := n.(*ir.CallExpr)
+			n.RType = r.rtype(pos)
+			// For append(a, b...), we don't need the implicit conversion. The typechecker already
+			// ensured that a and b are both slices with the same base type, or []byte and string.
+			if n.IsDDD {
+				if conv, ok := n.Args[1].(*ir.ConvExpr); ok && conv.Op() == ir.OCONVNOP && conv.Implicit() {
+					n.Args[1] = conv.X
+				}
+			}
+		case ir.OCOPY:
+			n := n.(*ir.BinaryExpr)
+			n.RType = r.rtype(pos)
+		case ir.ODELETE:
+			n := n.(*ir.CallExpr)
+			n.RType = r.rtype(pos)
+		case ir.OUNSAFESLICE:
+			n := n.(*ir.BinaryExpr)
+			n.RType = r.rtype(pos)
+		}
+		return n
+
+	case exprMake:
+		pos := r.pos()
+		typ := r.exprType()
+		extra := r.exprs()
+		n := typecheck.Expr(ir.NewCallExpr(pos, ir.OMAKE, nil, append([]ir.Node{typ}, extra...))).(*ir.MakeExpr)
+		n.RType = r.rtype(pos)
+		return n
+
+	case exprNew:
+		pos := r.pos()
+		typ := r.exprType()
+		return typecheck.Expr(ir.NewUnaryExpr(pos, ir.ONEW, typ))
+
+	case exprReshape:
+		typ := r.typ()
+		x := r.expr()
+
+		if types.IdenticalStrict(x.Type(), typ) {
+			return x
+		}
+
+		// Comparison expressions are constructed as "untyped bool" still.
+		//
+		// TODO(mdempsky): It should be safe to reshape them here too, but
+		// maybe it's better to construct them with the proper type
+		// instead.
+		if x.Type() == types.UntypedBool && typ.IsBoolean() {
+			return x
+		}
+
+		base.AssertfAt(x.Type().HasShape() || typ.HasShape(), x.Pos(), "%L and %v are not shape types", x, typ)
+		base.AssertfAt(types.Identical(x.Type(), typ), x.Pos(), "%L is not shape-identical to %v", x, typ)
+
+		// We use ir.HasUniquePos here as a check that x only appears once
+		// in the AST, so it's okay for us to call SetType without
+		// breaking any other uses of it.
+		//
+		// Notably, any ONAMEs should already have the exactly right shape
+		// type and been caught by types.IdenticalStrict above.
+		base.AssertfAt(ir.HasUniquePos(x), x.Pos(), "cannot call SetType(%v) on %L", typ, x)
+
+		if base.Debug.Reshape != 0 {
+			base.WarnfAt(x.Pos(), "reshaping %L to %v", x, typ)
+		}
+
+		x.SetType(typ)
+		return x
+
+	case exprConvert:
+		implicit := r.Bool()
+		typ := r.typ()
+		pos := r.pos()
+		typeWord, srcRType := r.convRTTI(pos)
+		dstTypeParam := r.Bool()
+		identical := r.Bool()
+		x := r.expr()
+
+		// TODO(mdempsky): Stop constructing expressions of untyped type.
+		x = typecheck.DefaultLit(x, typ)
+
+		ce := ir.NewConvExpr(pos, ir.OCONV, typ, x)
+		ce.TypeWord, ce.SrcRType = typeWord, srcRType
+		if implicit {
+			ce.SetImplicit(true)
+		}
+		n := typecheck.Expr(ce)
+
+		// Conversions between non-identical, non-empty interfaces always
+		// requires a runtime call, even if they have identical underlying
+		// interfaces. This is because we create separate itab instances
+		// for each unique interface type, not merely each unique
+		// interface shape.
+		//
+		// However, due to shape types, typecheck.Expr might mistakenly
+		// think a conversion between two non-empty interfaces are
+		// identical and set ir.OCONVNOP, instead of ir.OCONVIFACE. To
+		// ensure we update the itab field appropriately, we force it to
+		// ir.OCONVIFACE instead when shape types are involved.
+		//
+		// TODO(mdempsky): Are there other places we might get this wrong?
+		// Should this be moved down into typecheck.{Assign,Convert}op?
+		// This would be a non-issue if itabs were unique for each
+		// *underlying* interface type instead.
+		if !identical {
+			if n, ok := n.(*ir.ConvExpr); ok && n.Op() == ir.OCONVNOP && n.Type().IsInterface() && !n.Type().IsEmptyInterface() && (n.Type().HasShape() || n.X.Type().HasShape()) {
+				n.SetOp(ir.OCONVIFACE)
+			}
+		}
+
+		// spec: "If the type is a type parameter, the constant is converted
+		// into a non-constant value of the type parameter."
+		if dstTypeParam && ir.IsConstNode(n) {
+			// Wrap in an OCONVNOP node to ensure result is non-constant.
+			n = Implicit(ir.NewConvExpr(pos, ir.OCONVNOP, n.Type(), n))
+			n.SetTypecheck(1)
+		}
+		return n
+	}
+}
+
+// funcInst reads an instantiated function reference, and returns
+// three (possibly nil) expressions related to it:
+//
+// baseFn is always non-nil: it's either a function of the appropriate
+// type already, or it has an extra dictionary parameter as the first
+// parameter.
+//
+// If dictPtr is non-nil, then it's a dictionary argument that must be
+// passed as the first argument to baseFn.
+//
+// If wrapperFn is non-nil, then it's either the same as baseFn (if
+// dictPtr is nil), or it's semantically equivalent to currying baseFn
+// to pass dictPtr. (wrapperFn is nil when dictPtr is an expression
+// that needs to be computed dynamically.)
+//
+// For callers that are creating a call to the returned function, it's
+// best to emit a call to baseFn, and include dictPtr in the arguments
+// list as appropriate.
+//
+// For callers that want to return the function without invoking it,
+// they may return wrapperFn if it's non-nil; but otherwise, they need
+// to create their own wrapper.
+func (r *reader) funcInst(pos src.XPos) (wrapperFn, baseFn, dictPtr ir.Node) {
+	// Like in methodExpr, I'm pretty sure this isn't needed.
+	var implicits []*types.Type
+	if r.dict != nil {
+		implicits = r.dict.targs
+	}
+
+	if r.Bool() { // dynamic subdictionary
+		idx := r.Len()
+		info := r.dict.subdicts[idx]
+		explicits := r.p.typListIdx(info.explicits, r.dict)
+
+		baseFn = r.p.objIdx(info.idx, implicits, explicits, true).(*ir.Name)
+
+		// TODO(mdempsky): Is there a more robust way to get the
+		// dictionary pointer type here?
+		dictPtrType := baseFn.Type().Params().Field(0).Type
+		dictPtr = typecheck.Expr(ir.NewConvExpr(pos, ir.OCONVNOP, dictPtrType, r.dictWord(pos, r.dict.subdictsOffset()+idx)))
+
+		return
+	}
+
+	info := r.objInfo()
+	explicits := r.p.typListIdx(info.explicits, r.dict)
+
+	wrapperFn = r.p.objIdx(info.idx, implicits, explicits, false).(*ir.Name)
+	baseFn = r.p.objIdx(info.idx, implicits, explicits, true).(*ir.Name)
+
+	dictName := r.p.objDictName(info.idx, implicits, explicits)
+	dictPtr = typecheck.Expr(ir.NewAddrExpr(pos, dictName))
+
+	return
+}
+
+func (pr *pkgReader) objDictName(idx pkgbits.Index, implicits, explicits []*types.Type) *ir.Name {
+	rname := pr.newReader(pkgbits.RelocName, idx, pkgbits.SyncObject1)
+	_, sym := rname.qualifiedIdent()
+	tag := pkgbits.CodeObj(rname.Code(pkgbits.SyncCodeObj))
+
+	if tag == pkgbits.ObjStub {
+		assert(!sym.IsBlank())
+		if pri, ok := objReader[sym]; ok {
+			return pri.pr.objDictName(pri.idx, nil, explicits)
+		}
+		base.Fatalf("unresolved stub: %v", sym)
+	}
+
+	dict := pr.objDictIdx(sym, idx, implicits, explicits, false)
+
+	return pr.dictNameOf(dict)
+}
+
+// curry returns a function literal that calls fun with arg0 and
+// (optionally) arg1, accepting additional arguments to the function
+// literal as necessary to satisfy fun's signature.
+//
+// If nilCheck is true and arg0 is an interface value, then it's
+// checked to be non-nil as an initial step at the point of evaluating
+// the function literal itself.
+func (r *reader) curry(origPos src.XPos, ifaceHack bool, fun ir.Node, arg0, arg1 ir.Node) ir.Node {
+	var captured ir.Nodes
+	captured.Append(fun, arg0)
+	if arg1 != nil {
+		captured.Append(arg1)
+	}
+
+	params, results := syntheticSig(fun.Type())
+	params = params[len(captured)-1:] // skip curried parameters
+	typ := types.NewSignature(types.NoPkg, nil, nil, params, results)
+
+	addBody := func(pos src.XPos, r *reader, captured []ir.Node) {
+		recvs, params := r.syntheticArgs(pos)
+		assert(len(recvs) == 0)
+
+		fun := captured[0]
+
+		var args ir.Nodes
+		args.Append(captured[1:]...)
+		args.Append(params...)
+
+		r.syntheticTailCall(pos, fun, args)
+	}
+
+	return r.syntheticClosure(origPos, typ, ifaceHack, captured, addBody)
+}
+
+// methodExprWrap returns a function literal that changes method's
+// first parameter's type to recv, and uses implicits/deref/addr to
+// select the appropriate receiver parameter to pass to method.
+func (r *reader) methodExprWrap(origPos src.XPos, recv *types.Type, implicits []int, deref, addr bool, method, dictPtr ir.Node) ir.Node {
+	var captured ir.Nodes
+	captured.Append(method)
+
+	params, results := syntheticSig(method.Type())
+
+	// Change first parameter to recv.
+	params[0].Type = recv
+
+	// If we have a dictionary pointer argument to pass, then omit the
+	// underlying method expression's dictionary parameter from the
+	// returned signature too.
+	if dictPtr != nil {
+		captured.Append(dictPtr)
+		params = append(params[:1], params[2:]...)
+	}
+
+	typ := types.NewSignature(types.NoPkg, nil, nil, params, results)
+
+	addBody := func(pos src.XPos, r *reader, captured []ir.Node) {
+		recvs, args := r.syntheticArgs(pos)
+		assert(len(recvs) == 0)
+
+		fn := captured[0]
+
+		// Rewrite first argument based on implicits/deref/addr.
+		{
+			arg := args[0]
+			for _, ix := range implicits {
+				arg = Implicit(DotField(pos, arg, ix))
+			}
+			if deref {
+				arg = Implicit(Deref(pos, arg.Type().Elem(), arg))
+			} else if addr {
+				arg = Implicit(Addr(pos, arg))
+			}
+			args[0] = arg
+		}
+
+		// Insert dictionary argument, if provided.
+		if dictPtr != nil {
+			newArgs := make([]ir.Node, len(args)+1)
+			newArgs[0] = args[0]
+			newArgs[1] = captured[1]
+			copy(newArgs[2:], args[1:])
+			args = newArgs
+		}
+
+		r.syntheticTailCall(pos, fn, args)
+	}
+
+	return r.syntheticClosure(origPos, typ, false, captured, addBody)
+}
+
+// syntheticClosure constructs a synthetic function literal for
+// currying dictionary arguments. origPos is the position used for the
+// closure, which must be a non-inlined position. typ is the function
+// literal's signature type.
+//
+// captures is a list of expressions that need to be evaluated at the
+// point of function literal evaluation and captured by the function
+// literal. If ifaceHack is true and captures[1] is an interface type,
+// it's checked to be non-nil after evaluation.
+//
+// addBody is a callback function to populate the function body. The
+// list of captured values passed back has the captured variables for
+// use within the function literal, corresponding to the expressions
+// in captures.
+func (r *reader) syntheticClosure(origPos src.XPos, typ *types.Type, ifaceHack bool, captures ir.Nodes, addBody func(pos src.XPos, r *reader, captured []ir.Node)) ir.Node {
+	// isSafe reports whether n is an expression that we can safely
+	// defer to evaluating inside the closure instead, to avoid storing
+	// them into the closure.
+	//
+	// In practice this is always (and only) the wrappee function.
+	isSafe := func(n ir.Node) bool {
+		if n.Op() == ir.ONAME && n.(*ir.Name).Class == ir.PFUNC {
+			return true
+		}
+		if n.Op() == ir.OMETHEXPR {
+			return true
+		}
+
+		return false
+	}
+
+	// The ODCLFUNC and its body need to use the original position, but
+	// the OCLOSURE node and any Init statements should use the inlined
+	// position instead. See also the explanation in reader.funcLit.
+	inlPos := r.inlPos(origPos)
+
+	fn := ir.NewClosureFunc(origPos, r.curfn != nil)
+	fn.SetWrapper(true)
+	clo := fn.OClosure
+	clo.SetPos(inlPos)
+	ir.NameClosure(clo, r.curfn)
+
+	setType(fn.Nname, typ)
+	typecheck.Func(fn)
+	setType(clo, fn.Type())
+
+	var init ir.Nodes
+	for i, n := range captures {
+		if isSafe(n) {
+			continue // skip capture; can reference directly
+		}
+
+		tmp := r.tempCopy(inlPos, n, &init)
+		ir.NewClosureVar(origPos, fn, tmp)
+
+		// We need to nil check interface receivers at the point of method
+		// value evaluation, ugh.
+		if ifaceHack && i == 1 && n.Type().IsInterface() {
+			check := ir.NewUnaryExpr(inlPos, ir.OCHECKNIL, ir.NewUnaryExpr(inlPos, ir.OITAB, tmp))
+			init.Append(typecheck.Stmt(check))
+		}
+	}
+
+	pri := pkgReaderIndex{synthetic: func(pos src.XPos, r *reader) {
+		captured := make([]ir.Node, len(captures))
+		next := 0
+		for i, n := range captures {
+			if isSafe(n) {
+				captured[i] = n
+			} else {
+				captured[i] = r.closureVars[next]
+				next++
+			}
+		}
+		assert(next == len(r.closureVars))
+
+		addBody(origPos, r, captured)
+	}}
+	bodyReader[fn] = pri
+	pri.funcBody(fn)
+
+	// TODO(mdempsky): Remove hard-coding of typecheck.Target.
+	return ir.InitExpr(init, ir.UseClosure(clo, typecheck.Target))
+}
+
+// syntheticSig duplicates and returns the params and results lists
+// for sig, but renaming anonymous parameters so they can be assigned
+// ir.Names.
+func syntheticSig(sig *types.Type) (params, results []*types.Field) {
+	clone := func(params []*types.Field) []*types.Field {
+		res := make([]*types.Field, len(params))
+		for i, param := range params {
+			sym := param.Sym
+			if sym == nil || sym.Name == "_" {
+				sym = typecheck.LookupNum(".anon", i)
+			}
+			// TODO(mdempsky): It would be nice to preserve the original
+			// parameter positions here instead, but at least
+			// typecheck.NewMethodType replaces them with base.Pos, making
+			// them useless. Worse, the positions copied from base.Pos may
+			// have inlining contexts, which we definitely don't want here
+			// (e.g., #54625).
+			res[i] = types.NewField(base.AutogeneratedPos, sym, param.Type)
+			res[i].SetIsDDD(param.IsDDD())
+		}
+		return res
+	}
+
+	return clone(sig.Params().FieldSlice()), clone(sig.Results().FieldSlice())
+}
+
+func (r *reader) optExpr() ir.Node {
+	if r.Bool() {
+		return r.expr()
+	}
+	return nil
+}
+
+// methodExpr reads a method expression reference, and returns three
+// (possibly nil) expressions related to it:
+//
+// baseFn is always non-nil: it's either a function of the appropriate
+// type already, or it has an extra dictionary parameter as the second
+// parameter (i.e., immediately after the promoted receiver
+// parameter).
+//
+// If dictPtr is non-nil, then it's a dictionary argument that must be
+// passed as the second argument to baseFn.
+//
+// If wrapperFn is non-nil, then it's either the same as baseFn (if
+// dictPtr is nil), or it's semantically equivalent to currying baseFn
+// to pass dictPtr. (wrapperFn is nil when dictPtr is an expression
+// that needs to be computed dynamically.)
+//
+// For callers that are creating a call to the returned method, it's
+// best to emit a call to baseFn, and include dictPtr in the arguments
+// list as appropriate.
+//
+// For callers that want to return a method expression without
+// invoking it, they may return wrapperFn if it's non-nil; but
+// otherwise, they need to create their own wrapper.
+func (r *reader) methodExpr() (wrapperFn, baseFn, dictPtr ir.Node) {
+	recv := r.typ()
+	sig0 := r.typ()
+	pos := r.pos()
+	_, sym := r.selector()
+
+	// Signature type to return (i.e., recv prepended to the method's
+	// normal parameters list).
+	sig := typecheck.NewMethodType(sig0, recv)
+
+	if r.Bool() { // type parameter method expression
+		idx := r.Len()
+		word := r.dictWord(pos, r.dict.typeParamMethodExprsOffset()+idx)
+
+		// TODO(mdempsky): If the type parameter was instantiated with an
+		// interface type (i.e., embed.IsInterface()), then we could
+		// return the OMETHEXPR instead and save an indirection.
+
+		// We wrote the method expression's entry point PC into the
+		// dictionary, but for Go `func` values we need to return a
+		// closure (i.e., pointer to a structure with the PC as the first
+		// field). Because method expressions don't have any closure
+		// variables, we pun the dictionary entry as the closure struct.
+		fn := typecheck.Expr(ir.NewConvExpr(pos, ir.OCONVNOP, sig, ir.NewAddrExpr(pos, word)))
+		return fn, fn, nil
+	}
+
+	// TODO(mdempsky): I'm pretty sure this isn't needed: implicits is
+	// only relevant to locally defined types, but they can't have
+	// (non-promoted) methods.
+	var implicits []*types.Type
+	if r.dict != nil {
+		implicits = r.dict.targs
+	}
+
+	if r.Bool() { // dynamic subdictionary
+		idx := r.Len()
+		info := r.dict.subdicts[idx]
+		explicits := r.p.typListIdx(info.explicits, r.dict)
+
+		shapedObj := r.p.objIdx(info.idx, implicits, explicits, true).(*ir.Name)
+		shapedFn := shapedMethodExpr(pos, shapedObj, sym)
+
+		// TODO(mdempsky): Is there a more robust way to get the
+		// dictionary pointer type here?
+		dictPtrType := shapedFn.Type().Params().Field(1).Type
+		dictPtr := typecheck.Expr(ir.NewConvExpr(pos, ir.OCONVNOP, dictPtrType, r.dictWord(pos, r.dict.subdictsOffset()+idx)))
+
+		return nil, shapedFn, dictPtr
+	}
+
+	if r.Bool() { // static dictionary
+		info := r.objInfo()
+		explicits := r.p.typListIdx(info.explicits, r.dict)
+
+		shapedObj := r.p.objIdx(info.idx, implicits, explicits, true).(*ir.Name)
+		shapedFn := shapedMethodExpr(pos, shapedObj, sym)
+
+		dict := r.p.objDictName(info.idx, implicits, explicits)
+		dictPtr := typecheck.Expr(ir.NewAddrExpr(pos, dict))
+
+		// Check that dictPtr matches shapedFn's dictionary parameter.
+		if !types.Identical(dictPtr.Type(), shapedFn.Type().Params().Field(1).Type) {
+			base.FatalfAt(pos, "dict %L, but shaped method %L", dict, shapedFn)
+		}
+
+		// For statically known instantiations, we can take advantage of
+		// the stenciled wrapper.
+		base.AssertfAt(!recv.HasShape(), pos, "shaped receiver %v", recv)
+		wrapperFn := typecheck.Expr(ir.NewSelectorExpr(pos, ir.OXDOT, ir.TypeNode(recv), sym)).(*ir.SelectorExpr)
+		base.AssertfAt(types.Identical(sig, wrapperFn.Type()), pos, "wrapper %L does not have type %v", wrapperFn, sig)
+
+		return wrapperFn, shapedFn, dictPtr
+	}
+
+	// Simple method expression; no dictionary needed.
+	base.AssertfAt(!recv.HasShape() || recv.IsInterface(), pos, "shaped receiver %v", recv)
+	fn := typecheck.Expr(ir.NewSelectorExpr(pos, ir.OXDOT, ir.TypeNode(recv), sym)).(*ir.SelectorExpr)
+	return fn, fn, nil
+}
+
+// shapedMethodExpr returns the specified method on the given shaped
+// type.
+func shapedMethodExpr(pos src.XPos, obj *ir.Name, sym *types.Sym) *ir.SelectorExpr {
+	assert(obj.Op() == ir.OTYPE)
+
+	typ := obj.Type()
+	assert(typ.HasShape())
+
+	method := func() *types.Field {
+		for _, method := range typ.Methods().Slice() {
+			if method.Sym == sym {
+				return method
+			}
+		}
+
+		base.FatalfAt(pos, "failed to find method %v in shaped type %v", sym, typ)
+		panic("unreachable")
+	}()
+
+	// Construct an OMETHEXPR node.
+	recv := method.Type.Recv().Type
+	return typecheck.Expr(ir.NewSelectorExpr(pos, ir.OXDOT, ir.TypeNode(recv), sym)).(*ir.SelectorExpr)
+}
+
+func (r *reader) multiExpr() []ir.Node {
+	r.Sync(pkgbits.SyncMultiExpr)
+
+	if r.Bool() { // N:1
+		pos := r.pos()
+		expr := r.expr()
+
+		results := make([]ir.Node, r.Len())
+		as := ir.NewAssignListStmt(pos, ir.OAS2, nil, []ir.Node{expr})
+		as.Def = true
+		for i := range results {
+			tmp := r.temp(pos, r.typ())
+			as.PtrInit().Append(ir.NewDecl(pos, ir.ODCL, tmp))
+			as.Lhs.Append(tmp)
+
+			res := ir.Node(tmp)
+			if r.Bool() {
+				n := ir.NewConvExpr(pos, ir.OCONV, r.typ(), res)
+				n.TypeWord, n.SrcRType = r.convRTTI(pos)
+				n.SetImplicit(true)
+				res = typecheck.Expr(n)
+			}
+			results[i] = res
+		}
+
+		// TODO(mdempsky): Could use ir.InlinedCallExpr instead?
+		results[0] = ir.InitExpr([]ir.Node{typecheck.Stmt(as)}, results[0])
+		return results
+	}
+
+	// N:N
+	exprs := make([]ir.Node, r.Len())
+	if len(exprs) == 0 {
+		return nil
+	}
+	for i := range exprs {
+		exprs[i] = r.expr()
+	}
+	return exprs
+}
+
+// temp returns a new autotemp of the specified type.
+func (r *reader) temp(pos src.XPos, typ *types.Type) *ir.Name {
+	// See typecheck.typecheckargs.
+	curfn := r.curfn
+	if curfn == nil {
+		curfn = typecheck.InitTodoFunc
+	}
+
+	return typecheck.TempAt(pos, curfn, typ)
+}
+
+// tempCopy declares and returns a new autotemp initialized to the
+// value of expr.
+func (r *reader) tempCopy(pos src.XPos, expr ir.Node, init *ir.Nodes) *ir.Name {
+	if r.curfn == nil {
+		// Escape analysis doesn't know how to handle package-scope
+		// function literals with free variables (i.e., that capture
+		// temporary variables added to typecheck.InitTodoFunc).
+		//
+		// stencil.go works around this limitation by spilling values to
+		// global variables instead, but that causes the value to stay
+		// alive indefinitely; see go.dev/issue/54343.
+		//
+		// This code path (which implements the same workaround) isn't
+		// actually needed by unified IR, because it creates uses normal
+		// OMETHEXPR/OMETHVALUE nodes when statically-known instantiated
+		// types are used. But it's kept around for now because it's handy
+		// for testing that the generic fallback paths work correctly.
+		base.Fatalf("tempCopy called at package scope")
+
+		tmp := staticinit.StaticName(expr.Type())
+
+		assign := ir.NewAssignStmt(pos, tmp, expr)
+		assign.Def = true
+		tmp.Defn = assign
+
+		typecheck.Target.Decls = append(typecheck.Target.Decls, typecheck.Stmt(assign))
+
+		return tmp
+	}
+
+	tmp := r.temp(pos, expr.Type())
+
+	init.Append(typecheck.Stmt(ir.NewDecl(pos, ir.ODCL, tmp)))
+
+	assign := ir.NewAssignStmt(pos, tmp, expr)
+	assign.Def = true
+	init.Append(typecheck.Stmt(ir.NewAssignStmt(pos, tmp, expr)))
+
+	tmp.Defn = assign
+
+	return tmp
+}
+
+func (r *reader) compLit() ir.Node {
+	r.Sync(pkgbits.SyncCompLit)
+	pos := r.pos()
+	typ0 := r.typ()
+
+	typ := typ0
+	if typ.IsPtr() {
+		typ = typ.Elem()
+	}
+	if typ.Kind() == types.TFORW {
+		base.FatalfAt(pos, "unresolved composite literal type: %v", typ)
+	}
+	var rtype ir.Node
+	if typ.IsMap() {
+		rtype = r.rtype(pos)
+	}
+	isStruct := typ.Kind() == types.TSTRUCT
+
+	elems := make([]ir.Node, r.Len())
+	for i := range elems {
+		elemp := &elems[i]
+
+		if isStruct {
+			sk := ir.NewStructKeyExpr(r.pos(), typ.Field(r.Len()), nil)
+			*elemp, elemp = sk, &sk.Value
+		} else if r.Bool() {
+			kv := ir.NewKeyExpr(r.pos(), r.expr(), nil)
+			*elemp, elemp = kv, &kv.Value
+		}
+
+		*elemp = wrapName(r.pos(), r.expr())
+	}
+
+	lit := typecheck.Expr(ir.NewCompLitExpr(pos, ir.OCOMPLIT, typ, elems))
+	if rtype != nil {
+		lit := lit.(*ir.CompLitExpr)
+		lit.RType = rtype
+	}
+	if typ0.IsPtr() {
+		lit = typecheck.Expr(typecheck.NodAddrAt(pos, lit))
+		lit.SetType(typ0)
+	}
+	return lit
+}
+
+func wrapName(pos src.XPos, x ir.Node) ir.Node {
+	// These nodes do not carry line numbers.
+	// Introduce a wrapper node to give them the correct line.
+	switch ir.Orig(x).Op() {
+	case ir.OTYPE, ir.OLITERAL:
+		if x.Sym() == nil {
+			break
+		}
+		fallthrough
+	case ir.ONAME, ir.ONONAME, ir.ONIL:
+		p := ir.NewParenExpr(pos, x)
+		p.SetImplicit(true)
+		return p
+	}
+	return x
+}
+
+func (r *reader) funcLit() ir.Node {
+	r.Sync(pkgbits.SyncFuncLit)
+
+	// The underlying function declaration (including its parameters'
+	// positions, if any) need to remain the original, uninlined
+	// positions. This is because we track inlining-context on nodes so
+	// we can synthesize the extra implied stack frames dynamically when
+	// generating tracebacks, whereas those stack frames don't make
+	// sense *within* the function literal. (Any necessary inlining
+	// adjustments will have been applied to the call expression
+	// instead.)
+	//
+	// This is subtle, and getting it wrong leads to cycles in the
+	// inlining tree, which lead to infinite loops during stack
+	// unwinding (#46234, #54625).
+	//
+	// Note that we *do* want the inline-adjusted position for the
+	// OCLOSURE node, because that position represents where any heap
+	// allocation of the closure is credited (#49171).
+	r.suppressInlPos++
+	pos := r.pos()
+	xtype2 := r.signature(types.LocalPkg, nil)
+	r.suppressInlPos--
+
+	fn := ir.NewClosureFunc(pos, r.curfn != nil)
+	clo := fn.OClosure
+	clo.SetPos(r.inlPos(pos)) // see comment above
+	ir.NameClosure(clo, r.curfn)
+
+	setType(fn.Nname, xtype2)
+	typecheck.Func(fn)
+	setType(clo, fn.Type())
+
+	fn.ClosureVars = make([]*ir.Name, 0, r.Len())
+	for len(fn.ClosureVars) < cap(fn.ClosureVars) {
+		ir.NewClosureVar(r.pos(), fn, r.useLocal())
+	}
+	if param := r.dictParam; param != nil {
+		// If we have a dictionary parameter, capture it too. For
+		// simplicity, we capture it last and unconditionally.
+		ir.NewClosureVar(param.Pos(), fn, param)
+	}
+
+	r.addBody(fn, nil)
+
+	// TODO(mdempsky): Remove hard-coding of typecheck.Target.
+	return ir.UseClosure(clo, typecheck.Target)
+}
+
+func (r *reader) exprList() []ir.Node {
+	r.Sync(pkgbits.SyncExprList)
+	return r.exprs()
+}
+
+func (r *reader) exprs() []ir.Node {
+	r.Sync(pkgbits.SyncExprs)
+	nodes := make([]ir.Node, r.Len())
+	if len(nodes) == 0 {
+		return nil // TODO(mdempsky): Unclear if this matters.
+	}
+	for i := range nodes {
+		nodes[i] = r.expr()
+	}
+	return nodes
+}
+
+// dictWord returns an expression to return the specified
+// uintptr-typed word from the dictionary parameter.
+func (r *reader) dictWord(pos src.XPos, idx int) ir.Node {
+	base.AssertfAt(r.dictParam != nil, pos, "expected dictParam in %v", r.curfn)
+	return typecheck.Expr(ir.NewIndexExpr(pos, r.dictParam, ir.NewBasicLit(pos, constant.MakeInt64(int64(idx)))))
+}
+
+// rttiWord is like dictWord, but converts it to *byte (the type used
+// internally to represent *runtime._type and *runtime.itab).
+func (r *reader) rttiWord(pos src.XPos, idx int) ir.Node {
+	return typecheck.Expr(ir.NewConvExpr(pos, ir.OCONVNOP, types.NewPtr(types.Types[types.TUINT8]), r.dictWord(pos, idx)))
+}
+
+// rtype reads a type reference from the element bitstream, and
+// returns an expression of type *runtime._type representing that
+// type.
+func (r *reader) rtype(pos src.XPos) ir.Node {
+	_, rtype := r.rtype0(pos)
+	return rtype
+}
+
+func (r *reader) rtype0(pos src.XPos) (typ *types.Type, rtype ir.Node) {
+	r.Sync(pkgbits.SyncRType)
+	if r.Bool() { // derived type
+		idx := r.Len()
+		info := r.dict.rtypes[idx]
+		typ = r.p.typIdx(info, r.dict, true)
+		rtype = r.rttiWord(pos, r.dict.rtypesOffset()+idx)
+		return
+	}
+
+	typ = r.typ()
+	rtype = reflectdata.TypePtrAt(pos, typ)
+	return
+}
+
+// varDictIndex populates name.DictIndex if name is a derived type.
+func (r *reader) varDictIndex(name *ir.Name) {
+	if r.Bool() {
+		idx := 1 + r.dict.rtypesOffset() + r.Len()
+		if int(uint16(idx)) != idx {
+			base.FatalfAt(name.Pos(), "DictIndex overflow for %v: %v", name, idx)
+		}
+		name.DictIndex = uint16(idx)
+	}
+}
+
+// itab returns a (typ, iface) pair of types.
+//
+// typRType and ifaceRType are expressions that evaluate to the
+// *runtime._type for typ and iface, respectively.
+//
+// If typ is a concrete type and iface is a non-empty interface type,
+// then itab is an expression that evaluates to the *runtime.itab for
+// the pair. Otherwise, itab is nil.
+func (r *reader) itab(pos src.XPos) (typ *types.Type, typRType ir.Node, iface *types.Type, ifaceRType ir.Node, itab ir.Node) {
+	typ, typRType = r.rtype0(pos)
+	iface, ifaceRType = r.rtype0(pos)
+
+	idx := -1
+	if r.Bool() {
+		idx = r.Len()
+	}
+
+	if !typ.IsInterface() && iface.IsInterface() && !iface.IsEmptyInterface() {
+		if idx >= 0 {
+			itab = r.rttiWord(pos, r.dict.itabsOffset()+idx)
+		} else {
+			base.AssertfAt(!typ.HasShape(), pos, "%v is a shape type", typ)
+			base.AssertfAt(!iface.HasShape(), pos, "%v is a shape type", iface)
+
+			lsym := reflectdata.ITabLsym(typ, iface)
+			itab = typecheck.LinksymAddr(pos, lsym, types.Types[types.TUINT8])
+		}
+	}
+
+	return
+}
+
+// convRTTI returns expressions appropriate for populating an
+// ir.ConvExpr's TypeWord and SrcRType fields, respectively.
+func (r *reader) convRTTI(pos src.XPos) (typeWord, srcRType ir.Node) {
+	r.Sync(pkgbits.SyncConvRTTI)
+	src, srcRType0, dst, dstRType, itab := r.itab(pos)
+	if !dst.IsInterface() {
+		return
+	}
+
+	// See reflectdata.ConvIfaceTypeWord.
+	switch {
+	case dst.IsEmptyInterface():
+		if !src.IsInterface() {
+			typeWord = srcRType0 // direct eface construction
+		}
+	case !src.IsInterface():
+		typeWord = itab // direct iface construction
+	default:
+		typeWord = dstRType // convI2I
+	}
+
+	// See reflectdata.ConvIfaceSrcRType.
+	if !src.IsInterface() {
+		srcRType = srcRType0
+	}
+
+	return
+}
+
+func (r *reader) exprType() ir.Node {
+	r.Sync(pkgbits.SyncExprType)
+	pos := r.pos()
+
+	var typ *types.Type
+	var rtype, itab ir.Node
+
+	if r.Bool() {
+		typ, rtype, _, _, itab = r.itab(pos)
+		if !typ.IsInterface() {
+			rtype = nil // TODO(mdempsky): Leave set?
+		}
+	} else {
+		typ, rtype = r.rtype0(pos)
+
+		if !r.Bool() { // not derived
+			// TODO(mdempsky): ir.TypeNode should probably return a typecheck'd node.
+			n := ir.TypeNode(typ)
+			n.SetTypecheck(1)
+			return n
+		}
+	}
+
+	dt := ir.NewDynamicType(pos, rtype)
+	dt.ITab = itab
+	return typed(typ, dt)
+}
+
+func (r *reader) op() ir.Op {
+	r.Sync(pkgbits.SyncOp)
+	return ir.Op(r.Len())
+}
+
+// @@@ Package initialization
+
+func (r *reader) pkgInit(self *types.Pkg, target *ir.Package) {
+	cgoPragmas := make([][]string, r.Len())
+	for i := range cgoPragmas {
+		cgoPragmas[i] = r.Strings()
+	}
+	target.CgoPragmas = cgoPragmas
+
+	r.pkgDecls(target)
+
+	r.Sync(pkgbits.SyncEOF)
+}
+
+func (r *reader) pkgDecls(target *ir.Package) {
+	r.Sync(pkgbits.SyncDecls)
+	for {
+		switch code := codeDecl(r.Code(pkgbits.SyncDecl)); code {
+		default:
+			panic(fmt.Sprintf("unhandled decl: %v", code))
+
+		case declEnd:
+			return
+
+		case declFunc:
+			names := r.pkgObjs(target)
+			assert(len(names) == 1)
+			target.Decls = append(target.Decls, names[0].Func)
+
+		case declMethod:
+			typ := r.typ()
+			_, sym := r.selector()
+
+			method := typecheck.Lookdot1(nil, sym, typ, typ.Methods(), 0)
+			target.Decls = append(target.Decls, method.Nname.(*ir.Name).Func)
+
+		case declVar:
+			pos := r.pos()
+			names := r.pkgObjs(target)
+			values := r.exprList()
+
+			if len(names) > 1 && len(values) == 1 {
+				as := ir.NewAssignListStmt(pos, ir.OAS2, nil, values)
+				for _, name := range names {
+					as.Lhs.Append(name)
+					name.Defn = as
+				}
+				target.Decls = append(target.Decls, as)
+			} else {
+				for i, name := range names {
+					as := ir.NewAssignStmt(pos, name, nil)
+					if i < len(values) {
+						as.Y = values[i]
+					}
+					name.Defn = as
+					target.Decls = append(target.Decls, as)
+				}
+			}
+
+			if n := r.Len(); n > 0 {
+				assert(len(names) == 1)
+				embeds := make([]ir.Embed, n)
+				for i := range embeds {
+					embeds[i] = ir.Embed{Pos: r.pos(), Patterns: r.Strings()}
+				}
+				names[0].Embed = &embeds
+				target.Embeds = append(target.Embeds, names[0])
+			}
+
+		case declOther:
+			r.pkgObjs(target)
+		}
+	}
+}
+
+func (r *reader) pkgObjs(target *ir.Package) []*ir.Name {
+	r.Sync(pkgbits.SyncDeclNames)
+	nodes := make([]*ir.Name, r.Len())
+	for i := range nodes {
+		r.Sync(pkgbits.SyncDeclName)
+
+		name := r.obj().(*ir.Name)
+		nodes[i] = name
+
+		sym := name.Sym()
+		if sym.IsBlank() {
+			continue
+		}
+
+		switch name.Class {
+		default:
+			base.FatalfAt(name.Pos(), "unexpected class: %v", name.Class)
+
+		case ir.PEXTERN:
+			target.Externs = append(target.Externs, name)
+
+		case ir.PFUNC:
+			assert(name.Type().Recv() == nil)
+
+			// TODO(mdempsky): Cleaner way to recognize init?
+			if strings.HasPrefix(sym.Name, "init.") {
+				target.Inits = append(target.Inits, name.Func)
+			}
+		}
+
+		if types.IsExported(sym.Name) {
+			assert(!sym.OnExportList())
+			target.Exports = append(target.Exports, name)
+			sym.SetOnExportList(true)
+		}
+
+		if base.Flag.AsmHdr != "" {
+			assert(!sym.Asm())
+			target.Asms = append(target.Asms, name)
+			sym.SetAsm(true)
+		}
+	}
+
+	return nodes
+}
+
+// @@@ Inlining
+
+// unifiedHaveInlineBody reports whether we have the function body for
+// fn, so we can inline it.
+func unifiedHaveInlineBody(fn *ir.Func) bool {
+	if fn.Inl == nil {
+		return false
+	}
+
+	_, ok := bodyReaderFor(fn)
+	return ok
+}
+
+var inlgen = 0
+
+// unifiedInlineCall implements inline.NewInline by re-reading the function
+// body from its Unified IR export data.
+func unifiedInlineCall(call *ir.CallExpr, fn *ir.Func, inlIndex int) *ir.InlinedCallExpr {
+	// TODO(mdempsky): Turn callerfn into an explicit parameter.
+	callerfn := ir.CurFunc
+
+	pri, ok := bodyReaderFor(fn)
+	if !ok {
+		base.FatalfAt(call.Pos(), "cannot inline call to %v: missing inline body", fn)
+	}
+
+	if fn.Inl.Body == nil {
+		expandInline(fn, pri)
+	}
+
+	r := pri.asReader(pkgbits.RelocBody, pkgbits.SyncFuncBody)
+
+	// TODO(mdempsky): This still feels clumsy. Can we do better?
+	tmpfn := ir.NewFunc(fn.Pos())
+	tmpfn.Nname = ir.NewNameAt(fn.Nname.Pos(), callerfn.Sym())
+	tmpfn.Closgen = callerfn.Closgen
+	defer func() { callerfn.Closgen = tmpfn.Closgen }()
+
+	setType(tmpfn.Nname, fn.Type())
+	r.curfn = tmpfn
+
+	r.inlCaller = callerfn
+	r.inlCall = call
+	r.inlFunc = fn
+	r.inlTreeIndex = inlIndex
+	r.inlPosBases = make(map[*src.PosBase]*src.PosBase)
+
+	r.closureVars = make([]*ir.Name, len(r.inlFunc.ClosureVars))
+	for i, cv := range r.inlFunc.ClosureVars {
+		r.closureVars[i] = cv.Outer
+	}
+	if len(r.closureVars) != 0 && r.hasTypeParams() {
+		r.dictParam = r.closureVars[len(r.closureVars)-1] // dictParam is last; see reader.funcLit
+	}
+
+	r.funcargs(fn)
+
+	r.delayResults = fn.Inl.CanDelayResults
+
+	r.retlabel = typecheck.AutoLabel(".i")
+	inlgen++
+
+	init := ir.TakeInit(call)
+
+	// For normal function calls, the function callee expression
+	// may contain side effects. Make sure to preserve these,
+	// if necessary (#42703).
+	if call.Op() == ir.OCALLFUNC {
+		inline.CalleeEffects(&init, call.X)
+	}
+
+	var args ir.Nodes
+	if call.Op() == ir.OCALLMETH {
+		base.FatalfAt(call.Pos(), "OCALLMETH missed by typecheck")
+	}
+	args.Append(call.Args...)
+
+	// Create assignment to declare and initialize inlvars.
+	as2 := ir.NewAssignListStmt(call.Pos(), ir.OAS2, r.inlvars, args)
+	as2.Def = true
+	var as2init ir.Nodes
+	for _, name := range r.inlvars {
+		if ir.IsBlank(name) {
+			continue
+		}
+		// TODO(mdempsky): Use inlined position of name.Pos() instead?
+		name := name.(*ir.Name)
+		as2init.Append(ir.NewDecl(call.Pos(), ir.ODCL, name))
+		name.Defn = as2
+	}
+	as2.SetInit(as2init)
+	init.Append(typecheck.Stmt(as2))
+
+	if !r.delayResults {
+		// If not delaying retvars, declare and zero initialize the
+		// result variables now.
+		for _, name := range r.retvars {
+			// TODO(mdempsky): Use inlined position of name.Pos() instead?
+			name := name.(*ir.Name)
+			init.Append(ir.NewDecl(call.Pos(), ir.ODCL, name))
+			ras := ir.NewAssignStmt(call.Pos(), name, nil)
+			init.Append(typecheck.Stmt(ras))
+		}
+	}
+
+	// Add an inline mark just before the inlined body.
+	// This mark is inline in the code so that it's a reasonable spot
+	// to put a breakpoint. Not sure if that's really necessary or not
+	// (in which case it could go at the end of the function instead).
+	// Note issue 28603.
+	init.Append(ir.NewInlineMarkStmt(call.Pos().WithIsStmt(), int64(r.inlTreeIndex)))
+
+	nparams := len(r.curfn.Dcl)
+
+	ir.WithFunc(r.curfn, func() {
+		if !r.syntheticBody(call.Pos()) {
+			assert(r.Bool()) // have body
+
+			r.curfn.Body = r.stmts()
+			r.curfn.Endlineno = r.pos()
+		}
+
+		// TODO(mdempsky): This shouldn't be necessary. Inlining might
+		// read in new function/method declarations, which could
+		// potentially be recursively inlined themselves; but we shouldn't
+		// need to read in the non-inlined bodies for the declarations
+		// themselves. But currently it's an easy fix to #50552.
+		readBodies(typecheck.Target, true)
+
+		deadcode.Func(r.curfn)
+
+		// Replace any "return" statements within the function body.
+		var edit func(ir.Node) ir.Node
+		edit = func(n ir.Node) ir.Node {
+			if ret, ok := n.(*ir.ReturnStmt); ok {
+				n = typecheck.Stmt(r.inlReturn(ret))
+			}
+			ir.EditChildren(n, edit)
+			return n
+		}
+		edit(r.curfn)
+	})
+
+	body := ir.Nodes(r.curfn.Body)
+
+	// Quirkish: We need to eagerly prune variables added during
+	// inlining, but removed by deadcode.FuncBody above. Unused
+	// variables will get removed during stack frame layout anyway, but
+	// len(fn.Dcl) ends up influencing things like autotmp naming.
+
+	used := usedLocals(body)
+
+	for i, name := range r.curfn.Dcl {
+		if i < nparams || used.Has(name) {
+			name.Curfn = callerfn
+			callerfn.Dcl = append(callerfn.Dcl, name)
+
+			// Quirkish. TODO(mdempsky): Document why.
+			if name.AutoTemp() {
+				name.SetEsc(ir.EscUnknown)
+
+				if base.Flag.GenDwarfInl != 0 {
+					name.SetInlLocal(true)
+				} else {
+					name.SetPos(r.inlCall.Pos())
+				}
+			}
+		}
+	}
+
+	body.Append(ir.NewLabelStmt(call.Pos(), r.retlabel))
+
+	res := ir.NewInlinedCallExpr(call.Pos(), body, append([]ir.Node(nil), r.retvars...))
+	res.SetInit(init)
+	res.SetType(call.Type())
+	res.SetTypecheck(1)
+
+	// Inlining shouldn't add any functions to todoBodies.
+	assert(len(todoBodies) == 0)
+
+	return res
+}
+
+// inlReturn returns a statement that can substitute for the given
+// return statement when inlining.
+func (r *reader) inlReturn(ret *ir.ReturnStmt) *ir.BlockStmt {
+	pos := r.inlCall.Pos()
+
+	block := ir.TakeInit(ret)
+
+	if results := ret.Results; len(results) != 0 {
+		assert(len(r.retvars) == len(results))
+
+		as2 := ir.NewAssignListStmt(pos, ir.OAS2, append([]ir.Node(nil), r.retvars...), ret.Results)
+
+		if r.delayResults {
+			for _, name := range r.retvars {
+				// TODO(mdempsky): Use inlined position of name.Pos() instead?
+				name := name.(*ir.Name)
+				block.Append(ir.NewDecl(pos, ir.ODCL, name))
+				name.Defn = as2
+			}
+		}
+
+		block.Append(as2)
+	}
+
+	block.Append(ir.NewBranchStmt(pos, ir.OGOTO, r.retlabel))
+	return ir.NewBlockStmt(pos, block)
+}
+
+// expandInline reads in an extra copy of IR to populate
+// fn.Inl.{Dcl,Body}.
+func expandInline(fn *ir.Func, pri pkgReaderIndex) {
+	// TODO(mdempsky): Remove this function. It's currently needed by
+	// dwarfgen/dwarf.go:preInliningDcls, which requires fn.Inl.Dcl to
+	// create abstract function DIEs. But we should be able to provide it
+	// with the same information some other way.
+
+	fndcls := len(fn.Dcl)
+	topdcls := len(typecheck.Target.Decls)
+
+	tmpfn := ir.NewFunc(fn.Pos())
+	tmpfn.Nname = ir.NewNameAt(fn.Nname.Pos(), fn.Sym())
+	tmpfn.ClosureVars = fn.ClosureVars
+
+	{
+		r := pri.asReader(pkgbits.RelocBody, pkgbits.SyncFuncBody)
+		setType(tmpfn.Nname, fn.Type())
+
+		// Don't change parameter's Sym/Nname fields.
+		r.funarghack = true
+
+		r.funcBody(tmpfn)
+
+		ir.WithFunc(tmpfn, func() {
+			deadcode.Func(tmpfn)
+		})
+	}
+
+	used := usedLocals(tmpfn.Body)
+
+	for _, name := range tmpfn.Dcl {
+		if name.Class != ir.PAUTO || used.Has(name) {
+			name.Curfn = fn
+			fn.Inl.Dcl = append(fn.Inl.Dcl, name)
+		}
+	}
+	fn.Inl.Body = tmpfn.Body
+
+	// Double check that we didn't change fn.Dcl by accident.
+	assert(fndcls == len(fn.Dcl))
+
+	// typecheck.Stmts may have added function literals to
+	// typecheck.Target.Decls. Remove them again so we don't risk trying
+	// to compile them multiple times.
+	typecheck.Target.Decls = typecheck.Target.Decls[:topdcls]
+}
+
+// usedLocals returns a set of local variables that are used within body.
+func usedLocals(body []ir.Node) ir.NameSet {
+	var used ir.NameSet
+	ir.VisitList(body, func(n ir.Node) {
+		if n, ok := n.(*ir.Name); ok && n.Op() == ir.ONAME && n.Class == ir.PAUTO {
+			used.Add(n)
+		}
+	})
+	return used
+}
+
+// @@@ Method wrappers
+
+// needWrapperTypes lists types for which we may need to generate
+// method wrappers.
+var needWrapperTypes []*types.Type
+
+// haveWrapperTypes lists types for which we know we already have
+// method wrappers, because we found the type in an imported package.
+var haveWrapperTypes []*types.Type
+
+// needMethodValueWrappers lists methods for which we may need to
+// generate method value wrappers.
+var needMethodValueWrappers []methodValueWrapper
+
+// haveMethodValueWrappers lists methods for which we know we already
+// have method value wrappers, because we found it in an imported
+// package.
+var haveMethodValueWrappers []methodValueWrapper
+
+type methodValueWrapper struct {
+	rcvr   *types.Type
+	method *types.Field
+}
+
+func (r *reader) needWrapper(typ *types.Type) {
+	if typ.IsPtr() {
+		return
+	}
+
+	// If a type was found in an imported package, then we can assume
+	// that package (or one of its transitive dependencies) already
+	// generated method wrappers for it.
+	if r.importedDef() {
+		haveWrapperTypes = append(haveWrapperTypes, typ)
+	} else {
+		needWrapperTypes = append(needWrapperTypes, typ)
+	}
+}
+
+// importedDef reports whether r is reading from an imported and
+// non-generic element.
+//
+// If a type was found in an imported package, then we can assume that
+// package (or one of its transitive dependencies) already generated
+// method wrappers for it.
+//
+// Exception: If we're instantiating an imported generic type or
+// function, we might be instantiating it with type arguments not
+// previously seen before.
+//
+// TODO(mdempsky): Distinguish when a generic function or type was
+// instantiated in an imported package so that we can add types to
+// haveWrapperTypes instead.
+func (r *reader) importedDef() bool {
+	return r.p != localPkgReader && !r.hasTypeParams()
+}
+
+func MakeWrappers(target *ir.Package) {
+	// Only unified IR emits its own wrappers.
+	if base.Debug.Unified == 0 {
+		return
+	}
+
+	// always generate a wrapper for error.Error (#29304)
+	needWrapperTypes = append(needWrapperTypes, types.ErrorType)
+
+	seen := make(map[string]*types.Type)
+
+	for _, typ := range haveWrapperTypes {
+		wrapType(typ, target, seen, false)
+	}
+	haveWrapperTypes = nil
+
+	for _, typ := range needWrapperTypes {
+		wrapType(typ, target, seen, true)
+	}
+	needWrapperTypes = nil
+
+	for _, wrapper := range haveMethodValueWrappers {
+		wrapMethodValue(wrapper.rcvr, wrapper.method, target, false)
+	}
+	haveMethodValueWrappers = nil
+
+	for _, wrapper := range needMethodValueWrappers {
+		wrapMethodValue(wrapper.rcvr, wrapper.method, target, true)
+	}
+	needMethodValueWrappers = nil
+}
+
+func wrapType(typ *types.Type, target *ir.Package, seen map[string]*types.Type, needed bool) {
+	key := typ.LinkString()
+	if prev := seen[key]; prev != nil {
+		if !types.Identical(typ, prev) {
+			base.Fatalf("collision: types %v and %v have link string %q", typ, prev, key)
+		}
+		return
+	}
+	seen[key] = typ
+
+	if !needed {
+		// Only called to add to 'seen'.
+		return
+	}
+
+	if !typ.IsInterface() {
+		typecheck.CalcMethods(typ)
+	}
+	for _, meth := range typ.AllMethods().Slice() {
+		if meth.Sym.IsBlank() || !meth.IsMethod() {
+			base.FatalfAt(meth.Pos, "invalid method: %v", meth)
+		}
+
+		methodWrapper(0, typ, meth, target)
+
+		// For non-interface types, we also want *T wrappers.
+		if !typ.IsInterface() {
+			methodWrapper(1, typ, meth, target)
+
+			// For not-in-heap types, *T is a scalar, not pointer shaped,
+			// so the interface wrappers use **T.
+			if typ.NotInHeap() {
+				methodWrapper(2, typ, meth, target)
+			}
+		}
+	}
+}
+
+func methodWrapper(derefs int, tbase *types.Type, method *types.Field, target *ir.Package) {
+	wrapper := tbase
+	for i := 0; i < derefs; i++ {
+		wrapper = types.NewPtr(wrapper)
+	}
+
+	sym := ir.MethodSym(wrapper, method.Sym)
+	base.Assertf(!sym.Siggen(), "already generated wrapper %v", sym)
+	sym.SetSiggen(true)
+
+	wrappee := method.Type.Recv().Type
+	if types.Identical(wrapper, wrappee) ||
+		!types.IsMethodApplicable(wrapper, method) ||
+		!reflectdata.NeedEmit(tbase) {
+		return
+	}
+
+	// TODO(mdempsky): Use method.Pos instead?
+	pos := base.AutogeneratedPos
+
+	fn := newWrapperFunc(pos, sym, wrapper, method)
+
+	var recv ir.Node = fn.Nname.Type().Recv().Nname.(*ir.Name)
+
+	// For simple *T wrappers around T methods, panicwrap produces a
+	// nicer panic message.
+	if wrapper.IsPtr() && types.Identical(wrapper.Elem(), wrappee) {
+		cond := ir.NewBinaryExpr(pos, ir.OEQ, recv, types.BuiltinPkg.Lookup("nil").Def.(ir.Node))
+		then := []ir.Node{ir.NewCallExpr(pos, ir.OCALL, typecheck.LookupRuntime("panicwrap"), nil)}
+		fn.Body.Append(ir.NewIfStmt(pos, cond, then, nil))
+	}
+
+	// typecheck will add one implicit deref, if necessary,
+	// but not-in-heap types require more for their **T wrappers.
+	for i := 1; i < derefs; i++ {
+		recv = Implicit(ir.NewStarExpr(pos, recv))
+	}
+
+	addTailCall(pos, fn, recv, method)
+
+	finishWrapperFunc(fn, target)
+}
+
+func wrapMethodValue(recvType *types.Type, method *types.Field, target *ir.Package, needed bool) {
+	sym := ir.MethodSymSuffix(recvType, method.Sym, "-fm")
+	if sym.Uniq() {
+		return
+	}
+	sym.SetUniq(true)
+
+	// TODO(mdempsky): Use method.Pos instead?
+	pos := base.AutogeneratedPos
+
+	fn := newWrapperFunc(pos, sym, nil, method)
+	sym.Def = fn.Nname
+
+	// Declare and initialize variable holding receiver.
+	recv := ir.NewHiddenParam(pos, fn, typecheck.Lookup(".this"), recvType)
+
+	if !needed {
+		typecheck.Func(fn)
+		return
+	}
+
+	addTailCall(pos, fn, recv, method)
+
+	finishWrapperFunc(fn, target)
+}
+
+func newWrapperFunc(pos src.XPos, sym *types.Sym, wrapper *types.Type, method *types.Field) *ir.Func {
+	fn := ir.NewFunc(pos)
+	fn.SetDupok(true) // TODO(mdempsky): Leave unset for local, non-generic wrappers?
+
+	name := ir.NewNameAt(pos, sym)
+	ir.MarkFunc(name)
+	name.Func = fn
+	name.Defn = fn
+	fn.Nname = name
+
+	sig := newWrapperType(wrapper, method)
+	setType(name, sig)
+
+	// TODO(mdempsky): De-duplicate with similar logic in funcargs.
+	defParams := func(class ir.Class, params *types.Type) {
+		for _, param := range params.FieldSlice() {
+			name := ir.NewNameAt(param.Pos, param.Sym)
+			name.Class = class
+			setType(name, param.Type)
+
+			name.Curfn = fn
+			fn.Dcl = append(fn.Dcl, name)
+
+			param.Nname = name
+		}
+	}
+
+	defParams(ir.PPARAM, sig.Recvs())
+	defParams(ir.PPARAM, sig.Params())
+	defParams(ir.PPARAMOUT, sig.Results())
+
+	return fn
+}
+
+func finishWrapperFunc(fn *ir.Func, target *ir.Package) {
+	typecheck.Func(fn)
+
+	ir.WithFunc(fn, func() {
+		typecheck.Stmts(fn.Body)
+	})
+
+	// We generate wrappers after the global inlining pass,
+	// so we're responsible for applying inlining ourselves here.
+	// TODO(prattmic): plumb PGO.
+	inline.InlineCalls(fn, nil)
+
+	// The body of wrapper function after inlining may reveal new ir.OMETHVALUE node,
+	// we don't know whether wrapper function has been generated for it or not, so
+	// generate one immediately here.
+	ir.VisitList(fn.Body, func(n ir.Node) {
+		if n, ok := n.(*ir.SelectorExpr); ok && n.Op() == ir.OMETHVALUE {
+			wrapMethodValue(n.X.Type(), n.Selection, target, true)
+		}
+	})
+
+	target.Decls = append(target.Decls, fn)
+}
+
+// newWrapperType returns a copy of the given signature type, but with
+// the receiver parameter type substituted with recvType.
+// If recvType is nil, newWrapperType returns a signature
+// without a receiver parameter.
+func newWrapperType(recvType *types.Type, method *types.Field) *types.Type {
+	clone := func(params []*types.Field) []*types.Field {
+		res := make([]*types.Field, len(params))
+		for i, param := range params {
+			sym := param.Sym
+			if sym == nil || sym.Name == "_" {
+				sym = typecheck.LookupNum(".anon", i)
+			}
+			res[i] = types.NewField(param.Pos, sym, param.Type)
+			res[i].SetIsDDD(param.IsDDD())
+		}
+		return res
+	}
+
+	sig := method.Type
+
+	var recv *types.Field
+	if recvType != nil {
+		recv = types.NewField(sig.Recv().Pos, typecheck.Lookup(".this"), recvType)
+	}
+	params := clone(sig.Params().FieldSlice())
+	results := clone(sig.Results().FieldSlice())
+
+	return types.NewSignature(types.NoPkg, recv, nil, params, results)
+}
+
+func addTailCall(pos src.XPos, fn *ir.Func, recv ir.Node, method *types.Field) {
+	sig := fn.Nname.Type()
+	args := make([]ir.Node, sig.NumParams())
+	for i, param := range sig.Params().FieldSlice() {
+		args[i] = param.Nname.(*ir.Name)
+	}
+
+	// TODO(mdempsky): Support creating OTAILCALL, when possible. See reflectdata.methodWrapper.
+	// Not urgent though, because tail calls are currently incompatible with regabi anyway.
+
+	fn.SetWrapper(true) // TODO(mdempsky): Leave unset for tail calls?
+
+	dot := ir.NewSelectorExpr(pos, ir.OXDOT, recv, method.Sym)
+	call := typecheck.Call(pos, dot, args, method.Type.IsVariadic()).(*ir.CallExpr)
+
+	if method.Type.NumResults() == 0 {
+		fn.Body.Append(call)
+		return
+	}
+
+	ret := ir.NewReturnStmt(pos, nil)
+	ret.Results = []ir.Node{call}
+	fn.Body.Append(ret)
+}
+
+func setBasePos(pos src.XPos) {
+	// Set the position for any error messages we might print (e.g. too large types).
+	base.Pos = pos
+}
+
+// dictParamName is the name of the synthetic dictionary parameter
+// added to shaped functions.
+//
+// N.B., this variable name is known to Delve:
+// https://github.com/go-delve/delve/blob/cb91509630529e6055be845688fd21eb89ae8714/pkg/proc/eval.go#L28
+const dictParamName = ".dict"
+
+// shapeSig returns a copy of fn's signature, except adding a
+// dictionary parameter and promoting the receiver parameter (if any)
+// to a normal parameter.
+//
+// The parameter types.Fields are all copied too, so their Nname
+// fields can be initialized for use by the shape function.
+func shapeSig(fn *ir.Func, dict *readerDict) *types.Type {
+	sig := fn.Nname.Type()
+	oldRecv := sig.Recv()
+
+	var recv *types.Field
+	if oldRecv != nil {
+		recv = types.NewField(oldRecv.Pos, oldRecv.Sym, oldRecv.Type)
+	}
+
+	params := make([]*types.Field, 1+sig.Params().Fields().Len())
+	params[0] = types.NewField(fn.Pos(), fn.Sym().Pkg.Lookup(dictParamName), types.NewPtr(dict.varType()))
+	for i, param := range sig.Params().Fields().Slice() {
+		d := types.NewField(param.Pos, param.Sym, param.Type)
+		d.SetIsDDD(param.IsDDD())
+		params[1+i] = d
+	}
+
+	results := make([]*types.Field, sig.Results().Fields().Len())
+	for i, result := range sig.Results().Fields().Slice() {
+		results[i] = types.NewField(result.Pos, result.Sym, result.Type)
+	}
+
+	return types.NewSignature(types.LocalPkg, recv, nil, params, results)
+}
diff --git a/src/cmd/compile/internal/noder/scopes.go b/src/cmd/compile/internal/noder/scopes.go
new file mode 100644
index 0000000..eb51847
--- /dev/null
+++ b/src/cmd/compile/internal/noder/scopes.go
@@ -0,0 +1,64 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"strings"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/types2"
+)
+
+// recordScopes populates fn.Parents and fn.Marks based on the scoping
+// information provided by types2.
+func (g *irgen) recordScopes(fn *ir.Func, sig *syntax.FuncType) {
+	scope, ok := g.info.Scopes[sig]
+	if !ok {
+		base.FatalfAt(fn.Pos(), "missing scope for %v", fn)
+	}
+
+	for i, n := 0, scope.NumChildren(); i < n; i++ {
+		g.walkScope(scope.Child(i))
+	}
+
+	g.marker.WriteTo(fn)
+}
+
+func (g *irgen) walkScope(scope *types2.Scope) bool {
+	// types2 doesn't provide a proper API for determining the
+	// lexical element a scope represents, so we have to resort to
+	// string matching. Conveniently though, this allows us to
+	// skip both function types and function literals, neither of
+	// which are interesting to us here.
+	if strings.HasPrefix(scope.String(), "function scope ") {
+		return false
+	}
+
+	g.marker.Push(g.pos(scope))
+
+	haveVars := false
+	for _, name := range scope.Names() {
+		if obj, ok := scope.Lookup(name).(*types2.Var); ok && obj.Name() != "_" {
+			haveVars = true
+			break
+		}
+	}
+
+	for i, n := 0, scope.NumChildren(); i < n; i++ {
+		if g.walkScope(scope.Child(i)) {
+			haveVars = true
+		}
+	}
+
+	if haveVars {
+		g.marker.Pop(g.end(scope))
+	} else {
+		g.marker.Unpush()
+	}
+
+	return haveVars
+}
diff --git a/src/cmd/compile/internal/noder/sizes.go b/src/cmd/compile/internal/noder/sizes.go
new file mode 100644
index 0000000..107f4d0
--- /dev/null
+++ b/src/cmd/compile/internal/noder/sizes.go
@@ -0,0 +1,162 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+)
+
+// Code below based on go/types.StdSizes.
+// Intentional differences are marked with "gc:".
+
+type gcSizes struct{}
+
+func (s *gcSizes) Alignof(T types2.Type) int64 {
+	// For arrays and structs, alignment is defined in terms
+	// of alignment of the elements and fields, respectively.
+	switch t := T.Underlying().(type) {
+	case *types2.Array:
+		// spec: "For a variable x of array type: unsafe.Alignof(x)
+		// is the same as unsafe.Alignof(x[0]), but at least 1."
+		return s.Alignof(t.Elem())
+	case *types2.Struct:
+		if t.NumFields() == 0 && types2.IsSyncAtomicAlign64(T) {
+			// Special case: sync/atomic.align64 is an
+			// empty struct we recognize as a signal that
+			// the struct it contains must be
+			// 64-bit-aligned.
+			//
+			// This logic is equivalent to the logic in
+			// cmd/compile/internal/types/size.go:calcStructOffset
+			return 8
+		}
+
+		// spec: "For a variable x of struct type: unsafe.Alignof(x)
+		// is the largest of the values unsafe.Alignof(x.f) for each
+		// field f of x, but at least 1."
+		max := int64(1)
+		for i, nf := 0, t.NumFields(); i < nf; i++ {
+			if a := s.Alignof(t.Field(i).Type()); a > max {
+				max = a
+			}
+		}
+		return max
+	case *types2.Slice, *types2.Interface:
+		// Multiword data structures are effectively structs
+		// in which each element has size PtrSize.
+		return int64(types.PtrSize)
+	case *types2.Basic:
+		// Strings are like slices and interfaces.
+		if t.Info()&types2.IsString != 0 {
+			return int64(types.PtrSize)
+		}
+	}
+	a := s.Sizeof(T) // may be 0
+	// spec: "For a variable x of any type: unsafe.Alignof(x) is at least 1."
+	if a < 1 {
+		return 1
+	}
+	// complex{64,128} are aligned like [2]float{32,64}.
+	if isComplex(T) {
+		a /= 2
+	}
+	if a > int64(types.RegSize) {
+		return int64(types.RegSize)
+	}
+	return a
+}
+
+func isComplex(T types2.Type) bool {
+	basic, ok := T.Underlying().(*types2.Basic)
+	return ok && basic.Info()&types2.IsComplex != 0
+}
+
+func (s *gcSizes) Offsetsof(fields []*types2.Var) []int64 {
+	offsets := make([]int64, len(fields))
+	var o int64
+	for i, f := range fields {
+		typ := f.Type()
+		a := s.Alignof(typ)
+		o = types.RoundUp(o, a)
+		offsets[i] = o
+		o += s.Sizeof(typ)
+	}
+	return offsets
+}
+
+func (s *gcSizes) Sizeof(T types2.Type) int64 {
+	switch t := T.Underlying().(type) {
+	case *types2.Basic:
+		k := t.Kind()
+		if int(k) < len(basicSizes) {
+			if s := basicSizes[k]; s > 0 {
+				return int64(s)
+			}
+		}
+		switch k {
+		case types2.String:
+			return int64(types.PtrSize) * 2
+		case types2.Int, types2.Uint, types2.Uintptr, types2.UnsafePointer:
+			return int64(types.PtrSize)
+		}
+		panic(fmt.Sprintf("unimplemented basic: %v (kind %v)", T, k))
+	case *types2.Array:
+		n := t.Len()
+		if n <= 0 {
+			return 0
+		}
+		// n > 0
+		// gc: Size includes alignment padding.
+		return s.Sizeof(t.Elem()) * n
+	case *types2.Slice:
+		return int64(types.PtrSize) * 3
+	case *types2.Struct:
+		n := t.NumFields()
+		if n == 0 {
+			return 0
+		}
+		fields := make([]*types2.Var, n)
+		for i := range fields {
+			fields[i] = t.Field(i)
+		}
+		offsets := s.Offsetsof(fields)
+
+		// gc: The last field of a non-zero-sized struct is not allowed to
+		// have size 0.
+		last := s.Sizeof(fields[n-1].Type())
+		if last == 0 && offsets[n-1] > 0 {
+			last = 1
+		}
+
+		// gc: Size includes alignment padding.
+		return types.RoundUp(offsets[n-1]+last, s.Alignof(t))
+	case *types2.Interface:
+		return int64(types.PtrSize) * 2
+	case *types2.Chan, *types2.Map, *types2.Pointer, *types2.Signature:
+		return int64(types.PtrSize)
+	default:
+		panic(fmt.Sprintf("unimplemented type: %T", t))
+	}
+}
+
+var basicSizes = [...]byte{
+	types2.Invalid:    1,
+	types2.Bool:       1,
+	types2.Int8:       1,
+	types2.Int16:      2,
+	types2.Int32:      4,
+	types2.Int64:      8,
+	types2.Uint8:      1,
+	types2.Uint16:     2,
+	types2.Uint32:     4,
+	types2.Uint64:     8,
+	types2.Float32:    4,
+	types2.Float64:    8,
+	types2.Complex64:  8,
+	types2.Complex128: 16,
+}
diff --git a/src/cmd/compile/internal/noder/stencil.go b/src/cmd/compile/internal/noder/stencil.go
new file mode 100644
index 0000000..26a088e
--- /dev/null
+++ b/src/cmd/compile/internal/noder/stencil.go
@@ -0,0 +1,2334 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file will evolve, since we plan to do a mix of stenciling and passing
+// around dictionaries.
+
+package noder
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/objw"
+	"cmd/compile/internal/reflectdata"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/internal/obj"
+	"cmd/internal/src"
+	"fmt"
+	"go/constant"
+)
+
+// Enable extra consistency checks.
+const doubleCheck = false
+
+func assert(p bool) {
+	base.Assert(p)
+}
+
+// For outputting debug information on dictionary format and instantiated dictionaries
+// (type arg, derived types, sub-dictionary, and itab entries).
+var infoPrintMode = false
+
+func infoPrint(format string, a ...interface{}) {
+	if infoPrintMode {
+		fmt.Printf(format, a...)
+	}
+}
+
+var geninst genInst
+
+func BuildInstantiations() {
+	geninst.instInfoMap = make(map[*types.Sym]*instInfo)
+	geninst.buildInstantiations()
+	geninst.instInfoMap = nil
+}
+
+// buildInstantiations scans functions for generic function calls and methods, and
+// creates the required instantiations. It also creates instantiated methods for all
+// fully-instantiated generic types that have been encountered already or new ones
+// that are encountered during the instantiation process. It scans all declarations
+// in typecheck.Target.Decls first, before scanning any new instantiations created.
+func (g *genInst) buildInstantiations() {
+	// Instantiate the methods of instantiated generic types that we have seen so far.
+	g.instantiateMethods()
+
+	// Scan all currentdecls for call to generic functions/methods.
+	n := len(typecheck.Target.Decls)
+	for i := 0; i < n; i++ {
+		g.scanForGenCalls(typecheck.Target.Decls[i])
+	}
+
+	// Scan all new instantiations created due to g.instantiateMethods() and the
+	// scan of current decls. This loop purposely runs until no new
+	// instantiations are created.
+	for i := 0; i < len(g.newInsts); i++ {
+		g.scanForGenCalls(g.newInsts[i])
+	}
+
+	g.finalizeSyms()
+
+	// All the instantiations and dictionaries have been created. Now go through
+	// each new instantiation and transform the various operations that need to make
+	// use of their dictionary.
+	l := len(g.newInsts)
+	for _, fun := range g.newInsts {
+		info := g.instInfoMap[fun.Sym()]
+		g.dictPass(info)
+		if doubleCheck {
+			ir.Visit(info.fun, func(n ir.Node) {
+				if n.Op() != ir.OCONVIFACE {
+					return
+				}
+				c := n.(*ir.ConvExpr)
+				if c.X.Type().HasShape() && !c.X.Type().IsInterface() {
+					ir.Dump("BAD FUNCTION", info.fun)
+					ir.Dump("BAD CONVERSION", c)
+					base.Fatalf("converting shape type to interface")
+				}
+			})
+		}
+		if base.Flag.W > 1 {
+			ir.Dump(fmt.Sprintf("\ndictpass %v", info.fun), info.fun)
+		}
+	}
+	assert(l == len(g.newInsts))
+	g.newInsts = nil
+}
+
+// scanForGenCalls scans a single function (or global assignment), looking for
+// references to generic functions/methods. At each such reference, it creates any
+// required instantiation and transforms the reference.
+func (g *genInst) scanForGenCalls(decl ir.Node) {
+	switch decl.Op() {
+	case ir.ODCLFUNC:
+		if decl.Type().HasTParam() {
+			// Skip any generic functions
+			return
+		}
+		// transformCall() below depends on CurFunc being set.
+		ir.CurFunc = decl.(*ir.Func)
+
+	case ir.OAS, ir.OAS2, ir.OAS2DOTTYPE, ir.OAS2FUNC, ir.OAS2MAPR, ir.OAS2RECV, ir.OASOP:
+		// These are all the various kinds of global assignments,
+		// whose right-hand-sides might contain a function
+		// instantiation.
+
+	default:
+		// The other possible ops at the top level are ODCLCONST
+		// and ODCLTYPE, which don't have any function
+		// instantiations.
+		return
+	}
+
+	// Search for any function references using generic function/methods. Then
+	// create the needed instantiated function if it hasn't been created yet, and
+	// change to calling that function directly.
+	modified := false
+	closureRequired := false
+	// declInfo will be non-nil exactly if we are scanning an instantiated function
+	declInfo := g.instInfoMap[decl.Sym()]
+
+	ir.Visit(decl, func(n ir.Node) {
+		if n.Op() == ir.OFUNCINST {
+			// generic F, not immediately called
+			closureRequired = true
+		}
+		if (n.Op() == ir.OMETHEXPR || n.Op() == ir.OMETHVALUE) && len(deref(n.(*ir.SelectorExpr).X.Type()).RParams()) > 0 && !types.IsInterfaceMethod(n.(*ir.SelectorExpr).Selection.Type) {
+			// T.M or x.M, where T or x is generic, but not immediately
+			// called. Not necessary if the method selected is
+			// actually for an embedded interface field.
+			closureRequired = true
+		}
+		if n.Op() == ir.OCALL && n.(*ir.CallExpr).X.Op() == ir.OFUNCINST {
+			// We have found a function call using a generic function
+			// instantiation.
+			call := n.(*ir.CallExpr)
+			inst := call.X.(*ir.InstExpr)
+			nameNode, isMeth := g.getInstNameNode(inst)
+			targs := typecheck.TypesOf(inst.Targs)
+			st := g.getInstantiation(nameNode, targs, isMeth).fun
+			dictValue, usingSubdict := g.getDictOrSubdict(declInfo, n, nameNode, targs, isMeth)
+			if infoPrintMode {
+				dictkind := "Main dictionary"
+				if usingSubdict {
+					dictkind = "Sub-dictionary"
+				}
+				if inst.X.Op() == ir.OMETHVALUE {
+					fmt.Printf("%s in %v at generic method call: %v - %v\n", dictkind, decl, inst.X, call)
+				} else {
+					fmt.Printf("%s in %v at generic function call: %v - %v\n", dictkind, decl, inst.X, call)
+				}
+			}
+
+			// Transform the Call now, which changes OCALL to
+			// OCALLFUNC and does typecheckaste/assignconvfn. Do
+			// it before installing the instantiation, so we are
+			// checking against non-shape param types in
+			// typecheckaste.
+			transformCall(call)
+
+			// Replace the OFUNCINST with a direct reference to the
+			// new stenciled function
+			call.X = st.Nname
+			if inst.X.Op() == ir.OMETHVALUE {
+				// When we create an instantiation of a method
+				// call, we make it a function. So, move the
+				// receiver to be the first arg of the function
+				// call.
+				call.Args.Prepend(inst.X.(*ir.SelectorExpr).X)
+			}
+
+			// Add dictionary to argument list.
+			call.Args.Prepend(dictValue)
+			modified = true
+		}
+		if n.Op() == ir.OCALLMETH && n.(*ir.CallExpr).X.Op() == ir.ODOTMETH && len(deref(n.(*ir.CallExpr).X.Type().Recv().Type).RParams()) > 0 {
+			// Method call on a generic type, which was instantiated by stenciling.
+			// Method calls on explicitly instantiated types will have an OFUNCINST
+			// and are handled above.
+			call := n.(*ir.CallExpr)
+			meth := call.X.(*ir.SelectorExpr)
+			targs := deref(meth.Type().Recv().Type).RParams()
+
+			t := meth.X.Type()
+			baseType := deref(t).OrigType()
+			var gf *ir.Name
+			for _, m := range baseType.Methods().Slice() {
+				if meth.Sel == m.Sym {
+					gf = m.Nname.(*ir.Name)
+					break
+				}
+			}
+
+			// Transform the Call now, which changes OCALL
+			// to OCALLFUNC and does typecheckaste/assignconvfn.
+			transformCall(call)
+
+			st := g.getInstantiation(gf, targs, true).fun
+			dictValue, usingSubdict := g.getDictOrSubdict(declInfo, n, gf, targs, true)
+			if hasShapeTypes(targs) {
+				// We have to be using a subdictionary, since this is
+				// a generic method call.
+				assert(usingSubdict)
+			} else {
+				// We should use main dictionary, because the receiver is
+				// an instantiation already, see issue #53406.
+				assert(!usingSubdict)
+			}
+
+			// Transform to a function call, by appending the
+			// dictionary and the receiver to the args.
+			call.SetOp(ir.OCALLFUNC)
+			call.X = st.Nname
+			call.Args.Prepend(dictValue, meth.X)
+			modified = true
+		}
+	})
+
+	// If we found a reference to a generic instantiation that wasn't an
+	// immediate call, then traverse the nodes of decl again (with
+	// EditChildren rather than Visit), where we actually change the
+	// reference to the instantiation to a closure that captures the
+	// dictionary, then does a direct call.
+	// EditChildren is more expensive than Visit, so we only do this
+	// in the infrequent case of an OFUNCINST without a corresponding
+	// call.
+	if closureRequired {
+		modified = true
+		var edit func(ir.Node) ir.Node
+		var outer *ir.Func
+		if f, ok := decl.(*ir.Func); ok {
+			outer = f
+		}
+		edit = func(x ir.Node) ir.Node {
+			if x.Op() == ir.OFUNCINST {
+				child := x.(*ir.InstExpr).X
+				if child.Op() == ir.OMETHEXPR || child.Op() == ir.OMETHVALUE {
+					// Call EditChildren on child (x.X),
+					// not x, so that we don't do
+					// buildClosure() on the
+					// METHEXPR/METHVALUE nodes as well.
+					ir.EditChildren(child, edit)
+					return g.buildClosure(outer, x)
+				}
+			}
+			ir.EditChildren(x, edit)
+			switch {
+			case x.Op() == ir.OFUNCINST:
+				return g.buildClosure(outer, x)
+			case (x.Op() == ir.OMETHEXPR || x.Op() == ir.OMETHVALUE) &&
+				len(deref(x.(*ir.SelectorExpr).X.Type()).RParams()) > 0 &&
+				!types.IsInterfaceMethod(x.(*ir.SelectorExpr).Selection.Type):
+				return g.buildClosure(outer, x)
+			}
+			return x
+		}
+		edit(decl)
+	}
+	if base.Flag.W > 1 && modified {
+		ir.Dump(fmt.Sprintf("\nmodified %v", decl), decl)
+	}
+	ir.CurFunc = nil
+	// We may have seen new fully-instantiated generic types while
+	// instantiating any needed functions/methods in the above
+	// function. If so, instantiate all the methods of those types
+	// (which will then lead to more function/methods to scan in the loop).
+	g.instantiateMethods()
+}
+
+// buildClosure makes a closure to implement x, a OFUNCINST or OMETHEXPR/OMETHVALUE
+// of generic type. outer is the containing function (or nil if closure is
+// in a global assignment instead of a function).
+func (g *genInst) buildClosure(outer *ir.Func, x ir.Node) ir.Node {
+	pos := x.Pos()
+	var target *ir.Func   // target instantiated function/method
+	var dictValue ir.Node // dictionary to use
+	var rcvrValue ir.Node // receiver, if a method value
+	typ := x.Type()       // type of the closure
+	var outerInfo *instInfo
+	if outer != nil {
+		outerInfo = g.instInfoMap[outer.Sym()]
+	}
+	usingSubdict := false
+	valueMethod := false
+	if x.Op() == ir.OFUNCINST {
+		inst := x.(*ir.InstExpr)
+
+		// Type arguments we're instantiating with.
+		targs := typecheck.TypesOf(inst.Targs)
+
+		// Find the generic function/method.
+		var gf *ir.Name
+		if inst.X.Op() == ir.ONAME {
+			// Instantiating a generic function call.
+			gf = inst.X.(*ir.Name)
+		} else if inst.X.Op() == ir.OMETHVALUE {
+			// Instantiating a method value x.M.
+			se := inst.X.(*ir.SelectorExpr)
+			rcvrValue = se.X
+			gf = se.Selection.Nname.(*ir.Name)
+		} else {
+			panic("unhandled")
+		}
+
+		// target is the instantiated function we're trying to call.
+		// For functions, the target expects a dictionary as its first argument.
+		// For method values, the target expects a dictionary and the receiver
+		// as its first two arguments.
+		// dictValue is the value to use for the dictionary argument.
+		target = g.getInstantiation(gf, targs, rcvrValue != nil).fun
+		dictValue, usingSubdict = g.getDictOrSubdict(outerInfo, x, gf, targs, rcvrValue != nil)
+		if infoPrintMode {
+			dictkind := "Main dictionary"
+			if usingSubdict {
+				dictkind = "Sub-dictionary"
+			}
+			if rcvrValue == nil {
+				fmt.Printf("%s in %v for generic function value %v\n", dictkind, outer, inst.X)
+			} else {
+				fmt.Printf("%s in %v for generic method value %v\n", dictkind, outer, inst.X)
+			}
+		}
+	} else { // ir.OMETHEXPR or ir.METHVALUE
+		// Method expression T.M where T is a generic type.
+		se := x.(*ir.SelectorExpr)
+		if x.Op() == ir.OMETHVALUE {
+			rcvrValue = se.X
+		}
+
+		// se.X.Type() is the top-level type of the method expression. To
+		// correctly handle method expressions involving embedded fields,
+		// look up the generic method below using the type of the receiver
+		// of se.Selection, since that will be the type that actually has
+		// the method.
+		recv := deref(se.Selection.Type.Recv().Type)
+		targs := recv.RParams()
+		if len(targs) == 0 {
+			// The embedded type that actually has the method is not
+			// actually generic, so no need to build a closure.
+			return x
+		}
+		baseType := recv.OrigType()
+		var gf *ir.Name
+		for _, m := range baseType.Methods().Slice() {
+			if se.Sel == m.Sym {
+				gf = m.Nname.(*ir.Name)
+				break
+			}
+		}
+		if !gf.Type().Recv().Type.IsPtr() {
+			// Remember if value method, so we can detect (*T).M case.
+			valueMethod = true
+		}
+		target = g.getInstantiation(gf, targs, true).fun
+		dictValue, usingSubdict = g.getDictOrSubdict(outerInfo, x, gf, targs, true)
+		if infoPrintMode {
+			dictkind := "Main dictionary"
+			if usingSubdict {
+				dictkind = "Sub-dictionary"
+			}
+			fmt.Printf("%s in %v for method expression %v\n", dictkind, outer, x)
+		}
+	}
+
+	// Build a closure to implement a function instantiation.
+	//
+	//   func f[T any] (int, int) (int, int) { ...whatever... }
+	//
+	// Then any reference to f[int] not directly called gets rewritten to
+	//
+	//   .dictN := ... dictionary to use ...
+	//   func(a0, a1 int) (r0, r1 int) {
+	//     return .inst.f[int](.dictN, a0, a1)
+	//   }
+	//
+	// Similarly for method expressions,
+	//
+	//   type g[T any] ....
+	//   func (rcvr g[T]) f(a0, a1 int) (r0, r1 int) { ... }
+	//
+	// Any reference to g[int].f not directly called gets rewritten to
+	//
+	//   .dictN := ... dictionary to use ...
+	//   func(rcvr g[int], a0, a1 int) (r0, r1 int) {
+	//     return .inst.g[int].f(.dictN, rcvr, a0, a1)
+	//   }
+	//
+	// Also method values
+	//
+	//   var x g[int]
+	//
+	// Any reference to x.f not directly called gets rewritten to
+	//
+	//   .dictN := ... dictionary to use ...
+	//   x2 := x
+	//   func(a0, a1 int) (r0, r1 int) {
+	//     return .inst.g[int].f(.dictN, x2, a0, a1)
+	//   }
+
+	// Make a new internal function.
+	fn, formalParams, formalResults := startClosure(pos, outer, typ)
+	fn.SetWrapper(true) // See issue 52237
+
+	// This is the dictionary we want to use.
+	// It may be a constant, it may be the outer functions's dictionary, or it may be
+	// a subdictionary acquired from the outer function's dictionary.
+	// For the latter, dictVar is a variable in the outer function's scope, set to the subdictionary
+	// read from the outer function's dictionary.
+	var dictVar *ir.Name
+	var dictAssign *ir.AssignStmt
+	if outer != nil {
+		dictVar = ir.NewNameAt(pos, closureSym(outer, typecheck.LocalDictName, g.dnum))
+		g.dnum++
+		dictVar.Class = ir.PAUTO
+		typed(types.Types[types.TUINTPTR], dictVar)
+		dictVar.Curfn = outer
+		dictAssign = ir.NewAssignStmt(pos, dictVar, dictValue)
+		dictAssign.SetTypecheck(1)
+		dictVar.Defn = dictAssign
+		outer.Dcl = append(outer.Dcl, dictVar)
+	}
+	// assign the receiver to a temporary.
+	var rcvrVar *ir.Name
+	var rcvrAssign ir.Node
+	if rcvrValue != nil {
+		rcvrVar = ir.NewNameAt(pos, closureSym(outer, ".rcvr", g.dnum))
+		g.dnum++
+		typed(rcvrValue.Type(), rcvrVar)
+		rcvrAssign = ir.NewAssignStmt(pos, rcvrVar, rcvrValue)
+		rcvrAssign.SetTypecheck(1)
+		rcvrVar.Defn = rcvrAssign
+		if outer == nil {
+			rcvrVar.Class = ir.PEXTERN
+			typecheck.Target.Decls = append(typecheck.Target.Decls, rcvrAssign)
+			typecheck.Target.Externs = append(typecheck.Target.Externs, rcvrVar)
+		} else {
+			rcvrVar.Class = ir.PAUTO
+			rcvrVar.Curfn = outer
+			outer.Dcl = append(outer.Dcl, rcvrVar)
+		}
+	}
+
+	// Build body of closure. This involves just calling the wrapped function directly
+	// with the additional dictionary argument.
+
+	// First, figure out the dictionary argument.
+	var dict2Var ir.Node
+	if usingSubdict {
+		// Capture sub-dictionary calculated in the outer function
+		dict2Var = ir.CaptureName(pos, fn, dictVar)
+		typed(types.Types[types.TUINTPTR], dict2Var)
+	} else {
+		// Static dictionary, so can be used directly in the closure
+		dict2Var = dictValue
+	}
+	// Also capture the receiver variable.
+	var rcvr2Var *ir.Name
+	if rcvrValue != nil {
+		rcvr2Var = ir.CaptureName(pos, fn, rcvrVar)
+	}
+
+	// Build arguments to call inside the closure.
+	var args []ir.Node
+
+	// First the dictionary argument.
+	args = append(args, dict2Var)
+	// Then the receiver.
+	if rcvrValue != nil {
+		args = append(args, rcvr2Var)
+	}
+	// Then all the other arguments (including receiver for method expressions).
+	for i := 0; i < typ.NumParams(); i++ {
+		if x.Op() == ir.OMETHEXPR && i == 0 {
+			// If we are doing a method expression, we need to
+			// explicitly traverse any embedded fields in the receiver
+			// argument in order to call the method instantiation.
+			arg0 := formalParams[0].Nname.(ir.Node)
+			arg0 = typecheck.AddImplicitDots(ir.NewSelectorExpr(x.Pos(), ir.OXDOT, arg0, x.(*ir.SelectorExpr).Sel)).X
+			if valueMethod && arg0.Type().IsPtr() {
+				// For handling the (*T).M case: if we have a pointer
+				// receiver after following all the embedded fields,
+				// but it's a value method, add a star operator.
+				arg0 = ir.NewStarExpr(arg0.Pos(), arg0)
+			}
+			args = append(args, arg0)
+		} else {
+			args = append(args, formalParams[i].Nname.(*ir.Name))
+		}
+	}
+
+	// Build call itself.
+	var innerCall ir.Node = ir.NewCallExpr(pos, ir.OCALL, target.Nname, args)
+	innerCall.(*ir.CallExpr).IsDDD = typ.IsVariadic()
+	if len(formalResults) > 0 {
+		innerCall = ir.NewReturnStmt(pos, []ir.Node{innerCall})
+	}
+	// Finish building body of closure.
+	ir.CurFunc = fn
+	// TODO: set types directly here instead of using typecheck.Stmt
+	typecheck.Stmt(innerCall)
+	ir.CurFunc = nil
+	fn.Body = []ir.Node{innerCall}
+
+	// We're all done with the captured dictionary (and receiver, for method values).
+	ir.FinishCaptureNames(pos, outer, fn)
+
+	// Make a closure referencing our new internal function.
+	c := ir.UseClosure(fn.OClosure, typecheck.Target)
+	var init []ir.Node
+	if outer != nil {
+		init = append(init, dictAssign)
+	}
+	if rcvrValue != nil {
+		init = append(init, rcvrAssign)
+	}
+	return ir.InitExpr(init, c)
+}
+
+// instantiateMethods instantiates all the methods (and associated dictionaries) of
+// all fully-instantiated generic types that have been added to typecheck.instTypeList.
+// It continues until no more types are added to typecheck.instTypeList.
+func (g *genInst) instantiateMethods() {
+	for {
+		instTypeList := typecheck.GetInstTypeList()
+		if len(instTypeList) == 0 {
+			break
+		}
+		typecheck.ClearInstTypeList()
+		for _, typ := range instTypeList {
+			assert(!typ.HasShape())
+			// Mark runtime type as needed, since this ensures that the
+			// compiler puts out the needed DWARF symbols, when this
+			// instantiated type has a different package from the local
+			// package.
+			typecheck.NeedRuntimeType(typ)
+			// Lookup the method on the base generic type, since methods may
+			// not be set on imported instantiated types.
+			baseType := typ.OrigType()
+			for j := range typ.Methods().Slice() {
+				if baseType.Methods().Slice()[j].Nointerface() {
+					typ.Methods().Slice()[j].SetNointerface(true)
+				}
+				baseNname := baseType.Methods().Slice()[j].Nname.(*ir.Name)
+				// Eagerly generate the instantiations and dictionaries that implement these methods.
+				// We don't use the instantiations here, just generate them (and any
+				// further instantiations those generate, etc.).
+				// Note that we don't set the Func for any methods on instantiated
+				// types. Their signatures don't match so that would be confusing.
+				// Direct method calls go directly to the instantiations, implemented above.
+				// Indirect method calls use wrappers generated in reflectcall. Those wrappers
+				// will use these instantiations if they are needed (for interface tables or reflection).
+				_ = g.getInstantiation(baseNname, typ.RParams(), true)
+				_ = g.getDictionarySym(baseNname, typ.RParams(), true)
+			}
+		}
+	}
+}
+
+// getInstNameNode returns the name node for the method or function being instantiated, and a bool which is true if a method is being instantiated.
+func (g *genInst) getInstNameNode(inst *ir.InstExpr) (*ir.Name, bool) {
+	if meth, ok := inst.X.(*ir.SelectorExpr); ok {
+		return meth.Selection.Nname.(*ir.Name), true
+	} else {
+		return inst.X.(*ir.Name), false
+	}
+}
+
+// getDictOrSubdict returns, for a method/function call or reference (node n) in an
+// instantiation (described by instInfo), a node which is accessing a sub-dictionary
+// or main/static dictionary, as needed, and also returns a boolean indicating if a
+// sub-dictionary was accessed. nameNode is the particular function or method being
+// called/referenced, and targs are the type arguments.
+func (g *genInst) getDictOrSubdict(declInfo *instInfo, n ir.Node, nameNode *ir.Name, targs []*types.Type, isMeth bool) (ir.Node, bool) {
+	var dict ir.Node
+	usingSubdict := false
+	if declInfo != nil {
+		entry := -1
+		for i, de := range declInfo.dictInfo.subDictCalls {
+			if n == de.callNode {
+				entry = declInfo.dictInfo.startSubDict + i
+				break
+			}
+		}
+		// If the entry is not found, it may be that this node did not have
+		// any type args that depend on type params, so we need a main
+		// dictionary, not a sub-dictionary.
+		if entry >= 0 {
+			dict = getDictionaryEntry(n.Pos(), declInfo.dictParam, entry, declInfo.dictInfo.dictLen)
+			usingSubdict = true
+		}
+	}
+	if !usingSubdict {
+		dict = g.getDictionaryValue(n.Pos(), nameNode, targs, isMeth)
+	}
+	return dict, usingSubdict
+}
+
+// checkFetchBody checks if a generic body can be fetched, but hasn't been loaded
+// yet. If so, it imports the body.
+func checkFetchBody(nameNode *ir.Name) {
+	if nameNode.Func.Body == nil && nameNode.Func.Inl != nil {
+		// If there is no body yet but Func.Inl exists, then we can
+		// import the whole generic body.
+		assert(nameNode.Func.Inl.Cost == 1 && nameNode.Sym().Pkg != types.LocalPkg)
+		typecheck.ImportBody(nameNode.Func)
+		assert(nameNode.Func.Inl.Body != nil)
+		nameNode.Func.Body = nameNode.Func.Inl.Body
+		nameNode.Func.Dcl = nameNode.Func.Inl.Dcl
+	}
+}
+
+// getInstantiation gets the instantiation and dictionary of the function or method nameNode
+// with the type arguments shapes. If the instantiated function is not already
+// cached, then it calls genericSubst to create the new instantiation.
+func (g *genInst) getInstantiation(nameNode *ir.Name, shapes []*types.Type, isMeth bool) *instInfo {
+	if nameNode.Func == nil {
+		// If nameNode.Func is nil, this must be a reference to a method of
+		// an imported instantiated type. We will have already called
+		// g.instantiateMethods() on the fully-instantiated type, so
+		// g.instInfoMap[sym] will be non-nil below.
+		rcvr := nameNode.Type().Recv()
+		if rcvr == nil || !deref(rcvr.Type).IsFullyInstantiated() {
+			base.FatalfAt(nameNode.Pos(), "Unexpected function instantiation %v with no body", nameNode)
+		}
+	} else {
+		checkFetchBody(nameNode)
+	}
+
+	var tparams []*types.Type
+	if isMeth {
+		// Get the type params from the method receiver (after skipping
+		// over any pointer)
+		recvType := nameNode.Type().Recv().Type
+		recvType = deref(recvType)
+		if recvType.IsFullyInstantiated() {
+			// Get the type of the base generic type, so we get
+			// its original typeparams.
+			recvType = recvType.OrigType()
+		}
+		tparams = recvType.RParams()
+	} else {
+		fields := nameNode.Type().TParams().Fields().Slice()
+		tparams = make([]*types.Type, len(fields))
+		for i, f := range fields {
+			tparams[i] = f.Type
+		}
+	}
+
+	// Convert any non-shape type arguments to their shape, so we can reduce the
+	// number of instantiations we have to generate. You can actually have a mix
+	// of shape and non-shape arguments, because of inferred or explicitly
+	// specified concrete type args.
+	s1 := make([]*types.Type, len(shapes))
+	for i, t := range shapes {
+		var tparam *types.Type
+		// Shapes are grouped differently for structural types, so we
+		// pass the type param to Shapify(), so we can distinguish.
+		tparam = tparams[i]
+		if !t.IsShape() {
+			s1[i] = typecheck.Shapify(t, i, tparam)
+		} else {
+			// Already a shape, but make sure it has the correct index.
+			s1[i] = typecheck.Shapify(shapes[i].Underlying(), i, tparam)
+		}
+	}
+	shapes = s1
+
+	sym := typecheck.MakeFuncInstSym(nameNode.Sym(), shapes, false, isMeth)
+	info := g.instInfoMap[sym]
+	if info == nil {
+		// If instantiation doesn't exist yet, create it and add
+		// to the list of decls.
+		info = &instInfo{
+			dictInfo: &dictInfo{},
+		}
+		info.dictInfo.shapeToBound = make(map[*types.Type]*types.Type)
+
+		if sym.Def != nil {
+			// This instantiation must have been imported from another
+			// package (because it was needed for inlining), so we should
+			// not re-generate it and have conflicting definitions for the
+			// symbol (issue #50121). It will have already gone through the
+			// dictionary transformations of dictPass, so we don't actually
+			// need the info.dictParam and info.shapeToBound info filled in
+			// below. We just set the imported instantiation as info.fun.
+			assert(sym.Pkg != types.LocalPkg)
+			info.fun = sym.Def.(*ir.Name).Func
+			assert(info.fun != nil)
+			g.instInfoMap[sym] = info
+			return info
+		}
+
+		// genericSubst fills in info.dictParam and info.shapeToBound.
+		st := g.genericSubst(sym, nameNode, tparams, shapes, isMeth, info)
+		info.fun = st
+		g.instInfoMap[sym] = info
+
+		// getInstInfo fills in info.dictInfo.
+		g.getInstInfo(st, shapes, info)
+		if base.Flag.W > 1 {
+			ir.Dump(fmt.Sprintf("\nstenciled %v", st), st)
+		}
+
+		// This ensures that the linker drops duplicates of this instantiation.
+		// All just works!
+		st.SetDupok(true)
+		typecheck.Target.Decls = append(typecheck.Target.Decls, st)
+		g.newInsts = append(g.newInsts, st)
+	}
+	return info
+}
+
+// Struct containing info needed for doing the substitution as we create the
+// instantiation of a generic function with specified type arguments.
+type subster struct {
+	g           *genInst
+	isMethod    bool     // If a method is being instantiated
+	newf        *ir.Func // Func node for the new stenciled function
+	ts          typecheck.Tsubster
+	info        *instInfo // Place to put extra info in the instantiation
+	skipClosure bool      // Skip substituting closures
+
+	// Map from non-nil, non-ONAME node n to slice of all m, where m.Defn = n
+	defnMap map[ir.Node][]**ir.Name
+}
+
+// genericSubst returns a new function with name newsym. The function is an
+// instantiation of a generic function or method specified by namedNode with type
+// args shapes. For a method with a generic receiver, it returns an instantiated
+// function type where the receiver becomes the first parameter. For either a generic
+// method or function, a dictionary parameter is the added as the very first
+// parameter. genericSubst fills in info.dictParam and info.shapeToBound.
+func (g *genInst) genericSubst(newsym *types.Sym, nameNode *ir.Name, tparams []*types.Type, shapes []*types.Type, isMethod bool, info *instInfo) *ir.Func {
+	gf := nameNode.Func
+	// Pos of the instantiated function is same as the generic function
+	newf := ir.NewFunc(gf.Pos())
+	newf.Pragma = gf.Pragma // copy over pragmas from generic function to stenciled implementation.
+	newf.Endlineno = gf.Endlineno
+	newf.Nname = ir.NewNameAt(gf.Pos(), newsym)
+	newf.Nname.Func = newf
+	newf.Nname.Defn = newf
+	newsym.Def = newf.Nname
+	savef := ir.CurFunc
+	// transformCall/transformReturn (called during stenciling of the body)
+	// depend on ir.CurFunc being set.
+	ir.CurFunc = newf
+
+	assert(len(tparams) == len(shapes))
+
+	subst := &subster{
+		g:        g,
+		isMethod: isMethod,
+		newf:     newf,
+		info:     info,
+		ts: typecheck.Tsubster{
+			Tparams: tparams,
+			Targs:   shapes,
+			Vars:    make(map[*ir.Name]*ir.Name),
+		},
+		defnMap: make(map[ir.Node][]**ir.Name),
+	}
+
+	newf.Dcl = make([]*ir.Name, 0, len(gf.Dcl)+1)
+
+	// Create the needed dictionary param
+	dictionarySym := newsym.Pkg.Lookup(typecheck.LocalDictName)
+	dictionaryType := types.Types[types.TUINTPTR]
+	dictionaryName := ir.NewNameAt(gf.Pos(), dictionarySym)
+	typed(dictionaryType, dictionaryName)
+	dictionaryName.Class = ir.PPARAM
+	dictionaryName.Curfn = newf
+	newf.Dcl = append(newf.Dcl, dictionaryName)
+	for _, n := range gf.Dcl {
+		if n.Sym().Name == typecheck.LocalDictName {
+			panic("already has dictionary")
+		}
+		newf.Dcl = append(newf.Dcl, subst.localvar(n))
+	}
+	dictionaryArg := types.NewField(gf.Pos(), dictionarySym, dictionaryType)
+	dictionaryArg.Nname = dictionaryName
+	info.dictParam = dictionaryName
+
+	// We add the dictionary as the first parameter in the function signature.
+	// We also transform a method type to the corresponding function type
+	// (make the receiver be the next parameter after the dictionary).
+	oldt := nameNode.Type()
+	var args []*types.Field
+	args = append(args, dictionaryArg)
+	args = append(args, oldt.Recvs().FieldSlice()...)
+	args = append(args, oldt.Params().FieldSlice()...)
+
+	// Replace the types in the function signature via subst.fields.
+	// Ugly: also, we have to insert the Name nodes of the parameters/results into
+	// the function type. The current function type has no Nname fields set,
+	// because it came via conversion from the types2 type.
+	newt := types.NewSignature(oldt.Pkg(), nil, nil,
+		subst.fields(ir.PPARAM, args, newf.Dcl),
+		subst.fields(ir.PPARAMOUT, oldt.Results().FieldSlice(), newf.Dcl))
+
+	typed(newt, newf.Nname)
+	ir.MarkFunc(newf.Nname)
+	newf.SetTypecheck(1)
+
+	// Make sure name/type of newf is set before substituting the body.
+	newf.Body = subst.list(gf.Body)
+	if len(newf.Body) == 0 {
+		// Ensure the body is nonempty, for issue 49524.
+		// TODO: have some other way to detect the difference between
+		// a function declared with no body, vs. one with an empty body?
+		newf.Body = append(newf.Body, ir.NewBlockStmt(gf.Pos(), nil))
+	}
+
+	if len(subst.defnMap) > 0 {
+		base.Fatalf("defnMap is not empty")
+	}
+
+	for i, tp := range tparams {
+		info.dictInfo.shapeToBound[shapes[i]] = subst.ts.Typ(tp.Bound())
+	}
+
+	ir.CurFunc = savef
+
+	return subst.newf
+}
+
+// localvar creates a new name node for the specified local variable and enters it
+// in subst.vars. It substitutes type arguments for type parameters in the type of
+// name as needed.
+func (subst *subster) localvar(name *ir.Name) *ir.Name {
+	m := ir.NewNameAt(name.Pos(), name.Sym())
+	if name.IsClosureVar() {
+		m.SetIsClosureVar(true)
+	}
+	m.SetType(subst.ts.Typ(name.Type()))
+	m.BuiltinOp = name.BuiltinOp
+	m.Curfn = subst.newf
+	m.Class = name.Class
+	assert(name.Class != ir.PEXTERN && name.Class != ir.PFUNC)
+	m.Func = name.Func
+	subst.ts.Vars[name] = m
+	m.SetTypecheck(1)
+	m.DictIndex = name.DictIndex
+	if name.Defn != nil {
+		if name.Defn.Op() == ir.ONAME {
+			// This is a closure variable, so its Defn is the outer
+			// captured variable, which has already been substituted.
+			m.Defn = subst.node(name.Defn)
+		} else {
+			// The other values of Defn are nodes in the body of the
+			// function, so just remember the mapping so we can set Defn
+			// properly in node() when we create the new body node. We
+			// always call localvar() on all the local variables before
+			// we substitute the body.
+			slice := subst.defnMap[name.Defn]
+			subst.defnMap[name.Defn] = append(slice, &m)
+		}
+	}
+	if name.Outer != nil {
+		m.Outer = subst.node(name.Outer).(*ir.Name)
+	}
+
+	return m
+}
+
+// getDictionaryEntry gets the i'th entry in the dictionary dict.
+func getDictionaryEntry(pos src.XPos, dict *ir.Name, i int, size int) ir.Node {
+	// Convert dictionary to *[N]uintptr
+	// All entries in the dictionary are pointers. They all point to static data, though, so we
+	// treat them as uintptrs so the GC doesn't need to keep track of them.
+	d := ir.NewConvExpr(pos, ir.OCONVNOP, types.Types[types.TUNSAFEPTR], dict)
+	d.SetTypecheck(1)
+	d = ir.NewConvExpr(pos, ir.OCONVNOP, types.NewArray(types.Types[types.TUINTPTR], int64(size)).PtrTo(), d)
+	d.SetTypecheck(1)
+	types.CheckSize(d.Type().Elem())
+
+	// Load entry i out of the dictionary.
+	deref := ir.NewStarExpr(pos, d)
+	typed(d.Type().Elem(), deref)
+	idx := ir.NewConstExpr(constant.MakeUint64(uint64(i)), dict) // TODO: what to set orig to?
+	typed(types.Types[types.TUINTPTR], idx)
+	r := ir.NewIndexExpr(pos, deref, idx)
+	typed(types.Types[types.TUINTPTR], r)
+	return r
+}
+
+// getDictionaryEntryAddr gets the address of the i'th entry in dictionary dict.
+func getDictionaryEntryAddr(pos src.XPos, dict *ir.Name, i int, size int) ir.Node {
+	a := ir.NewAddrExpr(pos, getDictionaryEntry(pos, dict, i, size))
+	typed(types.Types[types.TUINTPTR].PtrTo(), a)
+	return a
+}
+
+// getDictionaryType returns a *runtime._type from the dictionary entry i (which
+// refers to a type param or a derived type that uses type params). It uses the
+// specified dictionary dictParam, rather than the one in info.dictParam.
+func getDictionaryType(info *instInfo, dictParam *ir.Name, pos src.XPos, i int) ir.Node {
+	if i < 0 || i >= info.dictInfo.startSubDict {
+		base.Fatalf(fmt.Sprintf("bad dict index %d", i))
+	}
+
+	r := getDictionaryEntry(pos, dictParam, i, info.dictInfo.startSubDict)
+	// change type of retrieved dictionary entry to *byte, which is the
+	// standard typing of a *runtime._type in the compiler
+	typed(types.Types[types.TUINT8].PtrTo(), r)
+	return r
+}
+
+// node is like DeepCopy(), but substitutes ONAME nodes based on subst.ts.vars, and
+// also descends into closures. It substitutes type arguments for type parameters in
+// all the new nodes and does the transformations that were delayed on the generic
+// function.
+func (subst *subster) node(n ir.Node) ir.Node {
+	// Use closure to capture all state needed by the ir.EditChildren argument.
+	var edit func(ir.Node) ir.Node
+	edit = func(x ir.Node) ir.Node {
+		// Analogous to ir.SetPos() at beginning of typecheck.typecheck() -
+		// allows using base.Pos during the transform functions, just like
+		// the tc*() functions.
+		ir.SetPos(x)
+		switch x.Op() {
+		case ir.OTYPE:
+			return ir.TypeNode(subst.ts.Typ(x.Type()))
+
+		case ir.ONAME:
+			if v := subst.ts.Vars[x.(*ir.Name)]; v != nil {
+				return v
+			}
+			if ir.IsBlank(x) {
+				// Special case, because a blank local variable is
+				// not in the fn.Dcl list.
+				m := ir.NewNameAt(x.Pos(), ir.BlankNode.Sym())
+				return typed(subst.ts.Typ(x.Type()), m)
+			}
+			return x
+		case ir.ONONAME:
+			// This handles the identifier in a type switch guard
+			fallthrough
+		case ir.OLITERAL, ir.ONIL:
+			if x.Sym() != nil {
+				return x
+			}
+		}
+		m := ir.Copy(x)
+
+		slice, ok := subst.defnMap[x]
+		if ok {
+			// We just copied a non-ONAME node which was the Defn value
+			// of a local variable. Set the Defn value of the copied
+			// local variable to this new Defn node.
+			for _, ptr := range slice {
+				(*ptr).Defn = m
+			}
+			delete(subst.defnMap, x)
+		}
+
+		if _, isExpr := m.(ir.Expr); isExpr {
+			t := x.Type()
+			if t == nil {
+				// Check for known cases where t can be nil (call
+				// that has no return values, and key expressions)
+				// and otherwise cause a fatal error.
+				_, isCallExpr := m.(*ir.CallExpr)
+				_, isStructKeyExpr := m.(*ir.StructKeyExpr)
+				_, isKeyExpr := m.(*ir.KeyExpr)
+				if !isCallExpr && !isStructKeyExpr && !isKeyExpr && x.Op() != ir.OPANIC &&
+					x.Op() != ir.OCLOSE {
+					base.FatalfAt(m.Pos(), "Nil type for %v", x)
+				}
+			} else if x.Op() != ir.OCLOSURE {
+				m.SetType(subst.ts.Typ(x.Type()))
+			}
+		}
+
+		old := subst.skipClosure
+		// For unsafe.{Alignof,Offsetof,Sizeof}, subster will transform them to OLITERAL nodes,
+		// and discard their arguments. However, their children nodes were already process before,
+		// thus if they contain any closure, the closure was still be added to package declarations
+		// queue for processing later. Thus, genInst will fail to generate instantiation for the
+		// closure because of lacking dictionary information, see issue #53390.
+		if call, ok := m.(*ir.CallExpr); ok && call.X.Op() == ir.ONAME {
+			switch call.X.Name().BuiltinOp {
+			case ir.OALIGNOF, ir.OOFFSETOF, ir.OSIZEOF:
+				subst.skipClosure = true
+			}
+		}
+		ir.EditChildren(m, edit)
+		subst.skipClosure = old
+
+		m.SetTypecheck(1)
+
+		// Do the transformations that we delayed on the generic function
+		// node, now that we have substituted in the type args.
+		switch x.Op() {
+		case ir.OEQ, ir.ONE, ir.OLT, ir.OLE, ir.OGT, ir.OGE:
+			transformCompare(m.(*ir.BinaryExpr))
+
+		case ir.OSLICE, ir.OSLICE3:
+			transformSlice(m.(*ir.SliceExpr))
+
+		case ir.OADD:
+			m = transformAdd(m.(*ir.BinaryExpr))
+
+		case ir.OINDEX:
+			transformIndex(m.(*ir.IndexExpr))
+
+		case ir.OAS2:
+			as2 := m.(*ir.AssignListStmt)
+			transformAssign(as2, as2.Lhs, as2.Rhs)
+
+		case ir.OAS:
+			as := m.(*ir.AssignStmt)
+			if as.Y != nil {
+				// transformAssign doesn't handle the case
+				// of zeroing assignment of a dcl (rhs[0] is nil).
+				lhs, rhs := []ir.Node{as.X}, []ir.Node{as.Y}
+				transformAssign(as, lhs, rhs)
+				as.X, as.Y = lhs[0], rhs[0]
+			}
+
+		case ir.OASOP:
+			as := m.(*ir.AssignOpStmt)
+			transformCheckAssign(as, as.X)
+
+		case ir.ORETURN:
+			transformReturn(m.(*ir.ReturnStmt))
+
+		case ir.OSEND:
+			transformSend(m.(*ir.SendStmt))
+
+		case ir.OSELECT:
+			transformSelect(m.(*ir.SelectStmt))
+
+		case ir.OCOMPLIT:
+			transformCompLit(m.(*ir.CompLitExpr))
+
+		case ir.OADDR:
+			transformAddr(m.(*ir.AddrExpr))
+
+		case ir.OLITERAL:
+			t := m.Type()
+			if t != x.Type() {
+				// types2 will give us a constant with a type T,
+				// if an untyped constant is used with another
+				// operand of type T (in a provably correct way).
+				// When we substitute in the type args during
+				// stenciling, we now know the real type of the
+				// constant. We may then need to change the
+				// BasicLit.val to be the correct type (e.g.
+				// convert an int64Val constant to a floatVal
+				// constant).
+				m.SetType(types.UntypedInt) // use any untyped type for DefaultLit to work
+				m = typecheck.DefaultLit(m, t)
+			}
+
+		case ir.OXDOT:
+			// Finish the transformation of an OXDOT, unless this is
+			// bound call or field access on a type param. A bound call
+			// or field access on a type param will be transformed during
+			// the dictPass. Otherwise, m will be transformed to an
+			// OMETHVALUE node. It will be transformed to an ODOTMETH or
+			// ODOTINTER node if we find in the OCALL case below that the
+			// method value is actually called.
+			mse := m.(*ir.SelectorExpr)
+			if src := mse.X.Type(); !src.IsShape() {
+				transformDot(mse, false)
+			}
+
+		case ir.OCALL:
+			call := m.(*ir.CallExpr)
+			switch call.X.Op() {
+			case ir.OTYPE:
+				// Transform the conversion, now that we know the
+				// type argument.
+				m = transformConvCall(call)
+
+			case ir.OMETHVALUE, ir.OMETHEXPR:
+				// Redo the transformation of OXDOT, now that we
+				// know the method value is being called. Then
+				// transform the call.
+				call.X.(*ir.SelectorExpr).SetOp(ir.OXDOT)
+				transformDot(call.X.(*ir.SelectorExpr), true)
+				transformCall(call)
+
+			case ir.ODOT, ir.ODOTPTR:
+				// An OXDOT for a generic receiver was resolved to
+				// an access to a field which has a function
+				// value. Transform the call to that function, now
+				// that the OXDOT was resolved.
+				transformCall(call)
+
+			case ir.ONAME:
+				name := call.X.Name()
+				if name.BuiltinOp != ir.OXXX {
+					m = transformBuiltin(call)
+				} else {
+					// This is the case of a function value that was a
+					// type parameter (implied to be a function via a
+					// structural constraint) which is now resolved.
+					transformCall(call)
+				}
+
+			case ir.OFUNCINST:
+				// A call with an OFUNCINST will get transformed
+				// in stencil() once we have created & attached the
+				// instantiation to be called.
+				// We must transform the arguments of the call now, though,
+				// so that any needed CONVIFACE nodes are exposed,
+				// so the dictionary format is correct.
+				transformEarlyCall(call)
+
+			case ir.OXDOT:
+				// This is the case of a bound call or a field access
+				// on a typeparam, which will be handled in the
+				// dictPass. As with OFUNCINST, we must transform the
+				// arguments of the call now, so any needed CONVIFACE
+				// nodes are exposed.
+				transformEarlyCall(call)
+
+			case ir.ODOTTYPE, ir.ODOTTYPE2:
+				// These are DOTTYPEs that could get transformed into
+				// ODYNAMIC DOTTYPEs by the dict pass.
+
+			default:
+				// Transform a call for all other values of
+				// call.X.Op() that don't require any special
+				// handling.
+				transformCall(call)
+
+			}
+
+		case ir.OCLOSURE:
+			if subst.skipClosure {
+				break
+			}
+			// We're going to create a new closure from scratch, so clear m
+			// to avoid using the ir.Copy by accident until we reassign it.
+			m = nil
+
+			x := x.(*ir.ClosureExpr)
+			// Need to duplicate x.Func.Nname, x.Func.Dcl, x.Func.ClosureVars, and
+			// x.Func.Body.
+			oldfn := x.Func
+			newfn := ir.NewClosureFunc(oldfn.Pos(), subst.newf != nil)
+			ir.NameClosure(newfn.OClosure, subst.newf)
+
+			saveNewf := subst.newf
+			ir.CurFunc = newfn
+			subst.newf = newfn
+			newfn.Dcl = subst.namelist(oldfn.Dcl)
+
+			// Make a closure variable for the dictionary of the
+			// containing function.
+			cdict := ir.CaptureName(oldfn.Pos(), newfn, subst.info.dictParam)
+			typed(types.Types[types.TUINTPTR], cdict)
+			ir.FinishCaptureNames(oldfn.Pos(), saveNewf, newfn)
+			newfn.ClosureVars = append(newfn.ClosureVars, subst.namelist(oldfn.ClosureVars)...)
+
+			// Copy that closure variable to a local one.
+			// Note: this allows the dictionary to be captured by child closures.
+			// See issue 47723.
+			ldict := ir.NewNameAt(x.Pos(), newfn.Sym().Pkg.Lookup(typecheck.LocalDictName))
+			typed(types.Types[types.TUINTPTR], ldict)
+			ldict.Class = ir.PAUTO
+			ldict.Curfn = newfn
+			newfn.Dcl = append(newfn.Dcl, ldict)
+			as := ir.NewAssignStmt(x.Pos(), ldict, cdict)
+			as.SetTypecheck(1)
+			ldict.Defn = as
+			newfn.Body.Append(as)
+
+			// Create inst info for the instantiated closure. The dict
+			// param is the closure variable for the dictionary of the
+			// outer function. Since the dictionary is shared, use the
+			// same dictInfo.
+			cinfo := &instInfo{
+				fun:       newfn,
+				dictParam: ldict,
+				dictInfo:  subst.info.dictInfo,
+			}
+			subst.g.instInfoMap[newfn.Nname.Sym()] = cinfo
+
+			typed(subst.ts.Typ(oldfn.Nname.Type()), newfn.Nname)
+			typed(newfn.Nname.Type(), newfn.OClosure)
+			newfn.SetTypecheck(1)
+
+			outerinfo := subst.info
+			subst.info = cinfo
+			// Make sure type of closure function is set before doing body.
+			newfn.Body.Append(subst.list(oldfn.Body)...)
+			subst.info = outerinfo
+			subst.newf = saveNewf
+			ir.CurFunc = saveNewf
+
+			m = ir.UseClosure(newfn.OClosure, typecheck.Target)
+			subst.g.newInsts = append(subst.g.newInsts, m.(*ir.ClosureExpr).Func)
+			m.(*ir.ClosureExpr).SetInit(subst.list(x.Init()))
+
+		case ir.OSWITCH:
+			m := m.(*ir.SwitchStmt)
+			if m.Tag != nil && m.Tag.Op() == ir.OTYPESW {
+				break // Nothing to do here for type switches.
+			}
+			if m.Tag != nil && !types.IsComparable(m.Tag.Type()) {
+				break // Nothing to do here for un-comparable types.
+			}
+			if m.Tag != nil && !m.Tag.Type().IsEmptyInterface() && m.Tag.Type().HasShape() {
+				// To implement a switch on a value that is or has a type parameter, we first convert
+				// that thing we're switching on to an interface{}.
+				m.Tag = assignconvfn(m.Tag, types.Types[types.TINTER])
+			}
+			for _, c := range m.Cases {
+				for i, x := range c.List {
+					// If we have a case that is or has a type parameter, convert that case
+					// to an interface{}.
+					if !x.Type().IsEmptyInterface() && x.Type().HasShape() {
+						c.List[i] = assignconvfn(x, types.Types[types.TINTER])
+					}
+				}
+			}
+
+		}
+		return m
+	}
+
+	return edit(n)
+}
+
+// dictPass takes a function instantiation and does the transformations on the
+// operations that need to make use of the dictionary param.
+func (g *genInst) dictPass(info *instInfo) {
+	savef := ir.CurFunc
+	ir.CurFunc = info.fun
+
+	callMap := make(map[ir.Node]bool)
+
+	var edit func(ir.Node) ir.Node
+	edit = func(m ir.Node) ir.Node {
+		if m.Op() == ir.OCALL && m.(*ir.CallExpr).X.Op() == ir.OXDOT {
+			callMap[m.(*ir.CallExpr).X] = true
+		}
+
+		ir.EditChildren(m, edit)
+
+		switch m.Op() {
+		case ir.OCLOSURE:
+			newf := m.(*ir.ClosureExpr).Func
+			ir.CurFunc = newf
+			outerinfo := info
+			info = g.instInfoMap[newf.Nname.Sym()]
+
+			body := newf.Body
+			for i, n := range body {
+				body[i] = edit(n)
+			}
+
+			info = outerinfo
+			ir.CurFunc = info.fun
+
+		case ir.OXDOT:
+			// This is the case of a dot access on a type param. This is
+			// typically a bound call on the type param, but could be a
+			// field access, if the constraint has a single structural type.
+			mse := m.(*ir.SelectorExpr)
+			src := mse.X.Type()
+			assert(src.IsShape())
+
+			if mse.X.Op() == ir.OTYPE {
+				// Method expression T.M
+				idx := findMethodExprClosure(info.dictInfo, mse)
+				c := getDictionaryEntryAddr(m.Pos(), info.dictParam, info.dictInfo.startMethodExprClosures+idx, info.dictInfo.dictLen)
+				m = ir.NewConvExpr(m.Pos(), ir.OCONVNOP, mse.Type(), c)
+				m.SetTypecheck(1)
+			} else {
+				// If we can't find the selected method in the
+				// AllMethods of the bound, then this must be an access
+				// to a field of a structural type. If so, we skip the
+				// dictionary lookups - transformDot() will convert to
+				// the desired direct field access.
+				if isBoundMethod(info.dictInfo, mse) {
+					if callMap[m] {
+						// The OCALL surrounding this XDOT will rewrite the call
+						// to use the method expression closure directly.
+						break
+					}
+					// Convert this method value to a closure.
+					// TODO: use method expression closure.
+					dst := info.dictInfo.shapeToBound[mse.X.Type()]
+					// Implement x.M as a conversion-to-bound-interface
+					//  1) convert x to the bound interface
+					//  2) select method value M on that interface
+					if src.IsInterface() {
+						// If type arg is an interface (unusual case),
+						// we do a type assert to the type bound.
+						mse.X = assertToBound(info, info.dictParam, m.Pos(), mse.X, dst)
+					} else {
+						mse.X = convertUsingDictionary(info, info.dictParam, m.Pos(), mse.X, m, dst)
+					}
+				}
+				transformDot(mse, false)
+			}
+		case ir.OCALL:
+			call := m.(*ir.CallExpr)
+			op := call.X.Op()
+			if op == ir.OXDOT {
+				// This is a call of a method value where the value has a type parameter type.
+				// We transform to a call of the appropriate method expression closure
+				// in the dictionary.
+				// So if x has a type parameter type:
+				//   _ = x.m(a)
+				// Rewrite to:
+				//   _ = methexpr<m>(x, a)
+				se := call.X.(*ir.SelectorExpr)
+				call.SetOp(ir.OCALLFUNC)
+				idx := findMethodExprClosure(info.dictInfo, se)
+				c := getDictionaryEntryAddr(se.Pos(), info.dictParam, info.dictInfo.startMethodExprClosures+idx, info.dictInfo.dictLen)
+				t := typecheck.NewMethodType(se.Type(), se.X.Type())
+				call.X = ir.NewConvExpr(se.Pos(), ir.OCONVNOP, t, c)
+				typed(t, call.X)
+				call.Args.Prepend(se.X)
+				break
+				// TODO: deref case?
+			}
+			if op == ir.OMETHVALUE {
+				// Redo the transformation of OXDOT, now that we
+				// know the method value is being called.
+				call.X.(*ir.SelectorExpr).SetOp(ir.OXDOT)
+				transformDot(call.X.(*ir.SelectorExpr), true)
+			}
+			transformCall(call)
+
+		case ir.OCONVIFACE:
+			if m.Type().IsEmptyInterface() && m.(*ir.ConvExpr).X.Type().IsEmptyInterface() {
+				// Was T->interface{}, after stenciling it is now interface{}->interface{}.
+				// No longer need the conversion. See issue 48276.
+				m.(*ir.ConvExpr).SetOp(ir.OCONVNOP)
+				break
+			}
+			mce := m.(*ir.ConvExpr)
+			// Note: x's argument is still typed as a type parameter.
+			// m's argument now has an instantiated type.
+			if mce.X.Type().HasShape() || (m.Type().HasShape() && !m.Type().IsEmptyInterface()) {
+				m = convertUsingDictionary(info, info.dictParam, m.Pos(), mce.X, m, m.Type())
+			}
+		case ir.ODOTTYPE, ir.ODOTTYPE2:
+			dt := m.(*ir.TypeAssertExpr)
+			if dt.Type().IsEmptyInterface() || (dt.Type().IsInterface() && !dt.Type().HasShape()) {
+				break
+			}
+			if !dt.Type().HasShape() && !(dt.X.Type().HasShape() && !dt.X.Type().IsEmptyInterface()) {
+				break
+			}
+			var rtype, itab ir.Node
+			if dt.Type().IsInterface() || dt.X.Type().IsEmptyInterface() {
+				// TODO(mdempsky): Investigate executing this block unconditionally.
+				ix := findDictType(info, m.Type())
+				assert(ix >= 0)
+				rtype = getDictionaryType(info, info.dictParam, dt.Pos(), ix)
+			} else {
+				// nonempty interface to noninterface. Need an itab.
+				ix := -1
+				for i, ic := range info.dictInfo.itabConvs {
+					if ic == m {
+						ix = info.dictInfo.startItabConv + i
+						break
+					}
+				}
+				assert(ix >= 0)
+				itab = getDictionaryEntry(dt.Pos(), info.dictParam, ix, info.dictInfo.dictLen)
+			}
+			op := ir.ODYNAMICDOTTYPE
+			if m.Op() == ir.ODOTTYPE2 {
+				op = ir.ODYNAMICDOTTYPE2
+			}
+			m = ir.NewDynamicTypeAssertExpr(dt.Pos(), op, dt.X, rtype)
+			m.(*ir.DynamicTypeAssertExpr).ITab = itab
+			m.SetType(dt.Type())
+			m.SetTypecheck(1)
+		case ir.OCASE:
+			if _, ok := m.(*ir.CommClause); ok {
+				// This is not a type switch. TODO: Should we use an OSWITCH case here instead of OCASE?
+				break
+			}
+			m := m.(*ir.CaseClause)
+			for i, c := range m.List {
+				if c.Op() == ir.OTYPE && c.Type().HasShape() {
+					// Use a *runtime._type for the dynamic type.
+					ix := findDictType(info, m.List[i].Type())
+					assert(ix >= 0)
+					dt := ir.NewDynamicType(c.Pos(), getDictionaryEntry(c.Pos(), info.dictParam, ix, info.dictInfo.dictLen))
+
+					// For type switch from nonempty interfaces to non-interfaces, we need an itab as well.
+					if !m.List[i].Type().IsInterface() {
+						if _, ok := info.dictInfo.type2switchType[m.List[i]]; ok {
+							// Type switch from nonempty interface. We need a *runtime.itab
+							// for the dynamic type.
+							ix := -1
+							for j, ic := range info.dictInfo.itabConvs {
+								if ic == m.List[i] {
+									ix = info.dictInfo.startItabConv + j
+									break
+								}
+							}
+							assert(ix >= 0)
+							dt.ITab = getDictionaryEntry(c.Pos(), info.dictParam, ix, info.dictInfo.dictLen)
+						}
+					}
+					typed(m.List[i].Type(), dt)
+					m.List[i] = dt
+				}
+			}
+
+		}
+		return m
+	}
+	edit(info.fun)
+	ir.CurFunc = savef
+}
+
+// findDictType looks for type t in the typeparams or derived types in the generic
+// function info.gfInfo. This will indicate the dictionary entry with the
+// correct concrete type for the associated instantiated function.
+func findDictType(info *instInfo, t *types.Type) int {
+	for i, dt := range info.dictInfo.shapeParams {
+		if dt == t {
+			return i
+		}
+	}
+	for i, dt := range info.dictInfo.derivedTypes {
+		if types.IdenticalStrict(dt, t) {
+			return i + len(info.dictInfo.shapeParams)
+		}
+	}
+	return -1
+}
+
+// convertUsingDictionary converts instantiated value v (type v.Type()) to an interface
+// type dst, by returning a new set of nodes that make use of a dictionary entry. in is the
+// instantiated node of the CONVIFACE node or XDOT node (for a bound method call) that is causing the
+// conversion.
+func convertUsingDictionary(info *instInfo, dictParam *ir.Name, pos src.XPos, v ir.Node, in ir.Node, dst *types.Type) ir.Node {
+	assert(v.Type().HasShape() || (in.Type().HasShape() && !in.Type().IsEmptyInterface()))
+	assert(dst.IsInterface())
+
+	if v.Type().IsInterface() {
+		// Converting from an interface. The shape-ness of the source doesn't really matter, as
+		// we'll be using the concrete type from the first interface word.
+		if dst.IsEmptyInterface() {
+			// Converting I2E. OCONVIFACE does that for us, and doesn't depend
+			// on what the empty interface was instantiated with. No dictionary entry needed.
+			v = ir.NewConvExpr(pos, ir.OCONVIFACE, dst, v)
+			v.SetTypecheck(1)
+			return v
+		}
+		if !in.Type().HasShape() {
+			// Regular OCONVIFACE works if the destination isn't parameterized.
+			v = ir.NewConvExpr(pos, ir.OCONVIFACE, dst, v)
+			v.SetTypecheck(1)
+			return v
+		}
+
+		// We get the destination interface type from the dictionary and the concrete
+		// type from the argument's itab. Call runtime.convI2I to get the new itab.
+		tmp := typecheck.Temp(v.Type())
+		as := ir.NewAssignStmt(pos, tmp, v)
+		as.SetTypecheck(1)
+		itab := ir.NewUnaryExpr(pos, ir.OITAB, tmp)
+		typed(types.Types[types.TUINTPTR].PtrTo(), itab)
+		idata := ir.NewUnaryExpr(pos, ir.OIDATA, tmp)
+		typed(types.Types[types.TUNSAFEPTR], idata)
+
+		fn := typecheck.LookupRuntime("convI2I")
+		fn.SetTypecheck(1)
+		types.CalcSize(fn.Type())
+		call := ir.NewCallExpr(pos, ir.OCALLFUNC, fn, nil)
+		typed(types.Types[types.TUINT8].PtrTo(), call)
+		ix := findDictType(info, in.Type())
+		assert(ix >= 0)
+		inter := getDictionaryType(info, dictParam, pos, ix)
+		call.Args = []ir.Node{inter, itab}
+		i := ir.NewBinaryExpr(pos, ir.OEFACE, call, idata)
+		typed(dst, i)
+		i.PtrInit().Append(as)
+		return i
+	}
+
+	var rt ir.Node
+	if !dst.IsEmptyInterface() {
+		// We should have an itab entry in the dictionary. Using this itab
+		// will be more efficient than converting to an empty interface first
+		// and then type asserting to dst.
+		ix := -1
+		for i, ic := range info.dictInfo.itabConvs {
+			if ic == in {
+				ix = info.dictInfo.startItabConv + i
+				break
+			}
+		}
+		assert(ix >= 0)
+		rt = getDictionaryEntry(pos, dictParam, ix, info.dictInfo.dictLen)
+	} else {
+		ix := findDictType(info, v.Type())
+		assert(ix >= 0)
+		// Load the actual runtime._type of the type parameter from the dictionary.
+		rt = getDictionaryType(info, dictParam, pos, ix)
+	}
+
+	// Figure out what the data field of the interface will be.
+	data := ir.NewConvExpr(pos, ir.OCONVIDATA, nil, v)
+	typed(types.Types[types.TUNSAFEPTR], data)
+
+	// Build an interface from the type and data parts.
+	var i ir.Node = ir.NewBinaryExpr(pos, ir.OEFACE, rt, data)
+	typed(dst, i)
+	return i
+}
+
+func (subst *subster) namelist(l []*ir.Name) []*ir.Name {
+	s := make([]*ir.Name, len(l))
+	for i, n := range l {
+		s[i] = subst.localvar(n)
+	}
+	return s
+}
+
+func (subst *subster) list(l []ir.Node) []ir.Node {
+	s := make([]ir.Node, len(l))
+	for i, n := range l {
+		s[i] = subst.node(n)
+	}
+	return s
+}
+
+// fields sets the Nname field for the Field nodes inside a type signature, based
+// on the corresponding in/out parameters in dcl. It depends on the in and out
+// parameters being in order in dcl.
+func (subst *subster) fields(class ir.Class, oldfields []*types.Field, dcl []*ir.Name) []*types.Field {
+	// Find the starting index in dcl of declarations of the class (either
+	// PPARAM or PPARAMOUT).
+	var i int
+	for i = range dcl {
+		if dcl[i].Class == class {
+			break
+		}
+	}
+
+	// Create newfields nodes that are copies of the oldfields nodes, but
+	// with substitution for any type params, and with Nname set to be the node in
+	// Dcl for the corresponding PPARAM or PPARAMOUT.
+	newfields := make([]*types.Field, len(oldfields))
+	for j := range oldfields {
+		newfields[j] = oldfields[j].Copy()
+		newfields[j].Type = subst.ts.Typ(oldfields[j].Type)
+		// A PPARAM field will be missing from dcl if its name is
+		// unspecified or specified as "_". So, we compare the dcl sym
+		// with the field sym (or sym of the field's Nname node). (Unnamed
+		// results still have a name like ~r2 in their Nname node.) If
+		// they don't match, this dcl (if there is one left) must apply to
+		// a later field.
+		if i < len(dcl) && (dcl[i].Sym() == oldfields[j].Sym ||
+			(oldfields[j].Nname != nil && dcl[i].Sym() == oldfields[j].Nname.Sym())) {
+			newfields[j].Nname = dcl[i]
+			i++
+		}
+	}
+	return newfields
+}
+
+// deref does a single deref of type t, if it is a pointer type.
+func deref(t *types.Type) *types.Type {
+	if t.IsPtr() {
+		return t.Elem()
+	}
+	return t
+}
+
+// markTypeUsed marks type t as used in order to help avoid dead-code elimination of
+// needed methods.
+func markTypeUsed(t *types.Type, lsym *obj.LSym) {
+	if t.IsInterface() {
+		return
+	}
+	// TODO: This is somewhat overkill, we really only need it
+	// for types that are put into interfaces.
+	// Note: this relocation is also used in cmd/link/internal/ld/dwarf.go
+	reflectdata.MarkTypeUsedInInterface(t, lsym)
+}
+
+// getDictionarySym returns the dictionary for the named generic function gf, which
+// is instantiated with the type arguments targs.
+func (g *genInst) getDictionarySym(gf *ir.Name, targs []*types.Type, isMeth bool) *types.Sym {
+	if len(targs) == 0 {
+		base.Fatalf("%s should have type arguments", gf.Sym().Name)
+	}
+
+	// Enforce that only concrete types can make it to here.
+	for _, t := range targs {
+		if t.HasShape() {
+			panic(fmt.Sprintf("shape %+v in dictionary for %s", t, gf.Sym().Name))
+		}
+	}
+
+	// Get a symbol representing the dictionary.
+	sym := typecheck.MakeDictSym(gf.Sym(), targs, isMeth)
+
+	// Initialize the dictionary, if we haven't yet already.
+	lsym := sym.Linksym()
+	if len(lsym.P) > 0 {
+		// We already started creating this dictionary and its lsym.
+		return sym
+	}
+
+	infoPrint("=== Creating dictionary %v\n", sym.Name)
+	off := 0
+	// Emit an entry for each targ (concrete type or gcshape).
+	for _, t := range targs {
+		infoPrint(" * %v\n", t)
+		s := reflectdata.TypeLinksym(t)
+		off = objw.SymPtr(lsym, off, s, 0)
+		markTypeUsed(t, lsym)
+	}
+
+	instInfo := g.getInstantiation(gf, targs, isMeth)
+	info := instInfo.dictInfo
+
+	subst := typecheck.Tsubster{
+		Tparams: info.shapeParams,
+		Targs:   targs,
+	}
+	// Emit an entry for each derived type (after substituting targs)
+	for _, t := range info.derivedTypes {
+		ts := subst.Typ(t)
+		infoPrint(" - %v\n", ts)
+		s := reflectdata.TypeLinksym(ts)
+		off = objw.SymPtr(lsym, off, s, 0)
+		markTypeUsed(ts, lsym)
+	}
+	// Emit an entry for each subdictionary (after substituting targs)
+	for _, subDictInfo := range info.subDictCalls {
+		var sym *types.Sym
+		n := subDictInfo.callNode
+		switch n.Op() {
+		case ir.OCALL, ir.OCALLFUNC, ir.OCALLMETH:
+			call := n.(*ir.CallExpr)
+			if call.X.Op() == ir.OXDOT || call.X.Op() == ir.ODOTMETH {
+				var nameNode *ir.Name
+				se := call.X.(*ir.SelectorExpr)
+				if se.X.Type().IsShape() {
+					tparam := se.X.Type()
+					// Ensure methods on all instantiating types are computed.
+					typecheck.CalcMethods(tparam)
+					if typecheck.Lookdot1(nil, se.Sel, tparam, tparam.AllMethods(), 0) != nil {
+						// This is a method call enabled by a type bound.
+						// We need this extra check for method expressions,
+						// which don't add in the implicit XDOTs.
+						tmpse := ir.NewSelectorExpr(src.NoXPos, ir.OXDOT, se.X, se.Sel)
+						tmpse = typecheck.AddImplicitDots(tmpse)
+						tparam = tmpse.X.Type()
+					}
+					if !tparam.IsShape() {
+						// The method expression is not
+						// really on a typeparam.
+						break
+					}
+					ix := -1
+					for i, shape := range info.shapeParams {
+						if shape == tparam {
+							ix = i
+							break
+						}
+					}
+					assert(ix >= 0)
+					recvType := targs[ix]
+					if recvType.IsInterface() || len(recvType.RParams()) == 0 {
+						// No sub-dictionary entry is
+						// actually needed, since the
+						// type arg is not an
+						// instantiated type that
+						// will have generic methods.
+						break
+					}
+					// This is a method call for an
+					// instantiated type, so we need a
+					// sub-dictionary.
+					targs := recvType.RParams()
+					genRecvType := recvType.OrigType()
+					nameNode = typecheck.Lookdot1(call.X, se.Sel, genRecvType, genRecvType.Methods(), 1).Nname.(*ir.Name)
+					sym = g.getDictionarySym(nameNode, targs, true)
+				} else {
+					// This is the case of a normal
+					// method call on a generic type.
+					assert(subDictInfo.savedXNode == se)
+					sym = g.getSymForMethodCall(se, &subst)
+				}
+			} else {
+				inst, ok := call.X.(*ir.InstExpr)
+				if ok {
+					// Code hasn't been transformed yet
+					assert(subDictInfo.savedXNode == inst)
+				}
+				// If !ok, then the generic method/function call has
+				// already been transformed to a shape instantiation
+				// call. Either way, use the SelectorExpr/InstExpr
+				// node saved in info.
+				cex := subDictInfo.savedXNode
+				if se, ok := cex.(*ir.SelectorExpr); ok {
+					sym = g.getSymForMethodCall(se, &subst)
+				} else {
+					inst := cex.(*ir.InstExpr)
+					nameNode := inst.X.(*ir.Name)
+					subtargs := typecheck.TypesOf(inst.Targs)
+					for i, t := range subtargs {
+						subtargs[i] = subst.Typ(t)
+					}
+					sym = g.getDictionarySym(nameNode, subtargs, false)
+				}
+			}
+
+		case ir.OFUNCINST:
+			inst := n.(*ir.InstExpr)
+			nameNode := inst.X.(*ir.Name)
+			subtargs := typecheck.TypesOf(inst.Targs)
+			for i, t := range subtargs {
+				subtargs[i] = subst.Typ(t)
+			}
+			sym = g.getDictionarySym(nameNode, subtargs, false)
+
+		case ir.OXDOT, ir.OMETHEXPR, ir.OMETHVALUE:
+			sym = g.getSymForMethodCall(n.(*ir.SelectorExpr), &subst)
+
+		default:
+			assert(false)
+		}
+
+		if sym == nil {
+			// Unused sub-dictionary entry, just emit 0.
+			off = objw.Uintptr(lsym, off, 0)
+			infoPrint(" - Unused subdict entry\n")
+		} else {
+			off = objw.SymPtr(lsym, off, sym.Linksym(), 0)
+			infoPrint(" - Subdict %v\n", sym.Name)
+		}
+	}
+
+	g.instantiateMethods()
+	delay := &delayInfo{
+		gf:     gf,
+		targs:  targs,
+		sym:    sym,
+		off:    off,
+		isMeth: isMeth,
+	}
+	g.dictSymsToFinalize = append(g.dictSymsToFinalize, delay)
+	return sym
+}
+
+// getSymForMethodCall gets the dictionary sym for a method call, method value, or method
+// expression that has selector se. subst gives the substitution from shape types to
+// concrete types.
+func (g *genInst) getSymForMethodCall(se *ir.SelectorExpr, subst *typecheck.Tsubster) *types.Sym {
+	// For everything except method expressions, 'recvType = deref(se.X.Type)' would
+	// also give the receiver type. For method expressions with embedded types, we
+	// need to look at the type of the selection to get the final receiver type.
+	recvType := deref(se.Selection.Type.Recv().Type)
+	genRecvType := recvType.OrigType()
+	nameNode := typecheck.Lookdot1(se, se.Sel, genRecvType, genRecvType.Methods(), 1).Nname.(*ir.Name)
+	subtargs := recvType.RParams()
+	s2targs := make([]*types.Type, len(subtargs))
+	for i, t := range subtargs {
+		s2targs[i] = subst.Typ(t)
+	}
+	return g.getDictionarySym(nameNode, s2targs, true)
+}
+
+// finalizeSyms finishes up all dictionaries on g.dictSymsToFinalize, by writing out
+// any needed LSyms for itabs. The itab lsyms create wrappers which need various
+// dictionaries and method instantiations to be complete, so, to avoid recursive
+// dependencies, we finalize the itab lsyms only after all dictionaries syms and
+// instantiations have been created.
+// Also handles writing method expression closures into the dictionaries.
+func (g *genInst) finalizeSyms() {
+Outer:
+	for _, d := range g.dictSymsToFinalize {
+		infoPrint("=== Finalizing dictionary %s\n", d.sym.Name)
+
+		lsym := d.sym.Linksym()
+		instInfo := g.getInstantiation(d.gf, d.targs, d.isMeth)
+		info := instInfo.dictInfo
+
+		subst := typecheck.Tsubster{
+			Tparams: info.shapeParams,
+			Targs:   d.targs,
+		}
+
+		// Emit an entry for each itab
+		for _, n := range info.itabConvs {
+			var srctype, dsttype *types.Type
+			switch n.Op() {
+			case ir.OXDOT, ir.OMETHVALUE:
+				se := n.(*ir.SelectorExpr)
+				srctype = subst.Typ(se.X.Type())
+				dsttype = subst.Typ(info.shapeToBound[se.X.Type()])
+			case ir.ODOTTYPE, ir.ODOTTYPE2:
+				srctype = subst.Typ(n.(*ir.TypeAssertExpr).Type())
+				dsttype = subst.Typ(n.(*ir.TypeAssertExpr).X.Type())
+			case ir.OCONVIFACE:
+				srctype = subst.Typ(n.(*ir.ConvExpr).X.Type())
+				dsttype = subst.Typ(n.Type())
+			case ir.OTYPE:
+				srctype = subst.Typ(n.Type())
+				dsttype = subst.Typ(info.type2switchType[n])
+			default:
+				base.Fatalf("itab entry with unknown op %s", n.Op())
+			}
+			if srctype.IsInterface() || dsttype.IsEmptyInterface() {
+				// No itab is wanted if src type is an interface. We
+				// will use a type assert instead.
+				d.off = objw.Uintptr(lsym, d.off, 0)
+				infoPrint(" + Unused itab entry for %v\n", srctype)
+			} else {
+				// Make sure all new fully-instantiated types have
+				// their methods created before generating any itabs.
+				g.instantiateMethods()
+				itabLsym := reflectdata.ITabLsym(srctype, dsttype)
+				d.off = objw.SymPtr(lsym, d.off, itabLsym, 0)
+				markTypeUsed(srctype, lsym)
+				infoPrint(" + Itab for (%v,%v)\n", srctype, dsttype)
+			}
+		}
+
+		// Emit an entry for each method expression closure.
+		// Each entry is a (captureless) closure pointing to the method on the instantiating type.
+		// In other words, the entry is a runtime.funcval whose fn field is set to the method
+		// in question, and has no other fields. The address of this dictionary entry can be
+		// cast to a func of the appropriate type.
+		// TODO: do these need to be done when finalizing, or can we do them earlier?
+		for _, bf := range info.methodExprClosures {
+			rcvr := d.targs[bf.idx]
+			rcvr2 := deref(rcvr)
+			found := false
+			typecheck.CalcMethods(rcvr2) // Ensure methods on all instantiating types are computed.
+			for _, f := range rcvr2.AllMethods().Slice() {
+				if f.Sym.Name == bf.name {
+					codePtr := ir.MethodSym(rcvr, f.Sym).Linksym()
+					d.off = objw.SymPtr(lsym, d.off, codePtr, 0)
+					infoPrint(" + MethodExprClosure for %v.%s\n", rcvr, bf.name)
+					found = true
+					break
+				}
+			}
+			if !found {
+				// We failed to find a method expression needed for this
+				// dictionary. This may happen because we tried to create a
+				// dictionary for an invalid instantiation.
+				//
+				// For example, in test/typeparam/issue54225.go, we attempt to
+				// construct a dictionary for "Node[struct{}].contentLen",
+				// even though "struct{}" does not implement "Value", so it
+				// cannot actually be used as a type argument to "Node".
+				//
+				// The real issue here is we shouldn't be attempting to create
+				// those dictionaries in the first place (e.g., CL 428356),
+				// but that fix is scarier for backporting to Go 1.19. Too
+				// many backport CLs to this code have fixed one issue while
+				// introducing another.
+				//
+				// So as a hack, instead of calling Fatalf, we simply skip
+				// calling objw.Global below, which prevents us from emitting
+				// the broken dictionary. The linker's dead code elimination
+				// should then naturally prune this invalid, unneeded
+				// dictionary. Worst case, if the dictionary somehow *is*
+				// needed by the final executable, we've just turned an ICE
+				// into a link-time missing symbol failure.
+				infoPrint(" ! abandoning dictionary %v; missing method expression %v.%s\n", d.sym.Name, rcvr, bf.name)
+				continue Outer
+			}
+		}
+
+		objw.Global(lsym, int32(d.off), obj.DUPOK|obj.RODATA)
+		infoPrint("=== Finalized dictionary %s\n", d.sym.Name)
+	}
+	g.dictSymsToFinalize = nil
+}
+
+func (g *genInst) getDictionaryValue(pos src.XPos, gf *ir.Name, targs []*types.Type, isMeth bool) ir.Node {
+	sym := g.getDictionarySym(gf, targs, isMeth)
+
+	// Make (or reuse) a node referencing the dictionary symbol.
+	var n *ir.Name
+	if sym.Def != nil {
+		n = sym.Def.(*ir.Name)
+	} else {
+		// We set the position of a static dictionary to be the position of
+		// one of its uses.
+		n = ir.NewNameAt(pos, sym)
+		n.Curfn = ir.CurFunc
+		n.SetType(types.Types[types.TUINTPTR]) // should probably be [...]uintptr, but doesn't really matter
+		n.SetTypecheck(1)
+		n.Class = ir.PEXTERN
+		sym.Def = n
+	}
+
+	// Return the address of the dictionary.  Addr node gets position that was passed in.
+	np := typecheck.NodAddrAt(pos, n)
+	// Note: treat dictionary pointers as uintptrs, so they aren't pointers
+	// with respect to GC. That saves on stack scanning work, write barriers, etc.
+	// We can get away with it because dictionaries are global variables.
+	// TODO: use a cast, or is typing directly ok?
+	np.SetType(types.Types[types.TUINTPTR])
+	np.SetTypecheck(1)
+	return np
+}
+
+// hasShapeNodes returns true if the type of any node in targs has a shape.
+func hasShapeNodes(targs []ir.Ntype) bool {
+	for _, n := range targs {
+		if n.Type().HasShape() {
+			return true
+		}
+	}
+	return false
+}
+
+// hasShapeTypes returns true if any type in targs has a shape.
+func hasShapeTypes(targs []*types.Type) bool {
+	for _, t := range targs {
+		if t.HasShape() {
+			return true
+		}
+	}
+	return false
+}
+
+// getInstInfo get the dictionary format for a function instantiation- type params, derived
+// types, and needed subdictionaries, itabs, and method expression closures.
+func (g *genInst) getInstInfo(st *ir.Func, shapes []*types.Type, instInfo *instInfo) {
+	info := instInfo.dictInfo
+	info.shapeParams = shapes
+
+	for _, t := range info.shapeParams {
+		b := info.shapeToBound[t]
+		if b.HasShape() {
+			// If a type bound is parameterized (unusual case), then we
+			// may need its derived type to do a type assert when doing a
+			// bound call for a type arg that is an interface.
+			addType(info, nil, b)
+		}
+	}
+
+	for _, n := range st.Dcl {
+		addType(info, n, n.Type())
+		n.DictIndex = uint16(findDictType(instInfo, n.Type()) + 1)
+	}
+
+	if infoPrintMode {
+		fmt.Printf(">>> InstInfo for %v\n", st)
+		for _, t := range info.shapeParams {
+			fmt.Printf("  Typeparam %v\n", t)
+		}
+	}
+
+	// Map to remember when we have seen an instantiated function value or method
+	// expression/value as part of a call, so we can determine when we encounter
+	// an uncalled function value or method expression/value.
+	callMap := make(map[ir.Node]bool)
+
+	var visitFunc func(ir.Node)
+	visitFunc = func(n ir.Node) {
+		switch n.Op() {
+		case ir.OFUNCINST:
+			if !callMap[n] && hasShapeNodes(n.(*ir.InstExpr).Targs) {
+				infoPrint("  Closure&subdictionary required at generic function value %v\n", n.(*ir.InstExpr).X)
+				info.subDictCalls = append(info.subDictCalls, subDictInfo{callNode: n, savedXNode: nil})
+			}
+		case ir.OMETHEXPR, ir.OMETHVALUE:
+			if !callMap[n] && !types.IsInterfaceMethod(n.(*ir.SelectorExpr).Selection.Type) &&
+				len(deref(n.(*ir.SelectorExpr).X.Type()).RParams()) > 0 &&
+				hasShapeTypes(deref(n.(*ir.SelectorExpr).X.Type()).RParams()) {
+				if n.(*ir.SelectorExpr).X.Op() == ir.OTYPE {
+					infoPrint("  Closure&subdictionary required at generic meth expr %v\n", n)
+				} else {
+					infoPrint("  Closure&subdictionary required at generic meth value %v\n", n)
+				}
+				info.subDictCalls = append(info.subDictCalls, subDictInfo{callNode: n, savedXNode: nil})
+			}
+		case ir.OCALL:
+			ce := n.(*ir.CallExpr)
+			if ce.X.Op() == ir.OFUNCINST {
+				callMap[ce.X] = true
+				if hasShapeNodes(ce.X.(*ir.InstExpr).Targs) {
+					infoPrint("  Subdictionary at generic function/method call: %v - %v\n", ce.X.(*ir.InstExpr).X, n)
+					// Save the instExpr node for the function call,
+					// since we will lose this information when the
+					// generic function call is transformed to a call
+					// on the shape instantiation.
+					info.subDictCalls = append(info.subDictCalls, subDictInfo{callNode: n, savedXNode: ce.X})
+				}
+			}
+			// Note: this XDOT code is not actually needed as long as we
+			// continue to disable type parameters on RHS of type
+			// declarations (#45639).
+			if ce.X.Op() == ir.OXDOT {
+				callMap[ce.X] = true
+				if isBoundMethod(info, ce.X.(*ir.SelectorExpr)) {
+					infoPrint("  Optional subdictionary at generic bound call: %v\n", n)
+					info.subDictCalls = append(info.subDictCalls, subDictInfo{callNode: n, savedXNode: nil})
+				}
+			}
+		case ir.OCALLMETH:
+			ce := n.(*ir.CallExpr)
+			if ce.X.Op() == ir.ODOTMETH &&
+				len(deref(ce.X.(*ir.SelectorExpr).X.Type()).RParams()) > 0 {
+				callMap[ce.X] = true
+				if hasShapeTypes(deref(ce.X.(*ir.SelectorExpr).X.Type()).RParams()) {
+					infoPrint("  Subdictionary at generic method call: %v\n", n)
+					// Save the selector for the method call, since we
+					// will eventually lose this information when the
+					// generic method call is transformed into a
+					// function call on the method shape instantiation.
+					info.subDictCalls = append(info.subDictCalls, subDictInfo{callNode: n, savedXNode: ce.X})
+				}
+			}
+		case ir.OCONVIFACE:
+			if n.Type().IsInterface() && !n.Type().IsEmptyInterface() &&
+				(n.Type().HasShape() || n.(*ir.ConvExpr).X.Type().HasShape()) {
+				infoPrint("  Itab for interface conv: %v\n", n)
+				info.itabConvs = append(info.itabConvs, n)
+			}
+		case ir.OXDOT:
+			se := n.(*ir.SelectorExpr)
+			if se.X.Op() == ir.OTYPE && se.X.Type().IsShape() {
+				// Method expression.
+				addMethodExprClosure(info, se)
+				break
+			}
+			if isBoundMethod(info, se) {
+				if callMap[n] {
+					// Method value called directly. Use method expression closure.
+					addMethodExprClosure(info, se)
+					break
+				}
+				// Method value not called directly. Still doing the old way.
+				infoPrint("  Itab for bound call: %v\n", n)
+				info.itabConvs = append(info.itabConvs, n)
+			}
+
+		case ir.ODOTTYPE, ir.ODOTTYPE2:
+			if !n.(*ir.TypeAssertExpr).Type().IsInterface() && !n.(*ir.TypeAssertExpr).X.Type().IsEmptyInterface() {
+				infoPrint("  Itab for dot type: %v\n", n)
+				info.itabConvs = append(info.itabConvs, n)
+			}
+		case ir.OCLOSURE:
+			// Visit the closure body and add all relevant entries to the
+			// dictionary of the outer function (closure will just use
+			// the dictionary of the outer function).
+			cfunc := n.(*ir.ClosureExpr).Func
+			for _, n1 := range cfunc.Body {
+				ir.Visit(n1, visitFunc)
+			}
+			for _, n := range cfunc.Dcl {
+				n.DictIndex = uint16(findDictType(instInfo, n.Type()) + 1)
+			}
+		case ir.OSWITCH:
+			ss := n.(*ir.SwitchStmt)
+			if ss.Tag != nil && ss.Tag.Op() == ir.OTYPESW &&
+				!ss.Tag.(*ir.TypeSwitchGuard).X.Type().IsEmptyInterface() {
+				for _, cc := range ss.Cases {
+					for _, c := range cc.List {
+						if c.Op() == ir.OTYPE && c.Type().HasShape() {
+							// Type switch from a non-empty interface - might need an itab.
+							infoPrint("  Itab for type switch: %v\n", c)
+							info.itabConvs = append(info.itabConvs, c)
+							if info.type2switchType == nil {
+								info.type2switchType = map[ir.Node]*types.Type{}
+							}
+							info.type2switchType[c] = ss.Tag.(*ir.TypeSwitchGuard).X.Type()
+						}
+					}
+				}
+			}
+		}
+		addType(info, n, n.Type())
+	}
+
+	for _, stmt := range st.Body {
+		ir.Visit(stmt, visitFunc)
+	}
+	if infoPrintMode {
+		for _, t := range info.derivedTypes {
+			fmt.Printf("  Derived type %v\n", t)
+		}
+		fmt.Printf(">>> Done Instinfo\n")
+	}
+	info.startSubDict = len(info.shapeParams) + len(info.derivedTypes)
+	info.startItabConv = len(info.shapeParams) + len(info.derivedTypes) + len(info.subDictCalls)
+	info.startMethodExprClosures = len(info.shapeParams) + len(info.derivedTypes) + len(info.subDictCalls) + len(info.itabConvs)
+	info.dictLen = len(info.shapeParams) + len(info.derivedTypes) + len(info.subDictCalls) + len(info.itabConvs) + len(info.methodExprClosures)
+}
+
+// isBoundMethod returns true if the selection indicated by se is a bound method of
+// se.X. se.X must be a shape type (i.e. substituted directly from a type param). If
+// isBoundMethod returns false, then the selection must be a field access of a
+// structural type.
+func isBoundMethod(info *dictInfo, se *ir.SelectorExpr) bool {
+	bound := info.shapeToBound[se.X.Type()]
+	return typecheck.Lookdot1(se, se.Sel, bound, bound.AllMethods(), 1) != nil
+}
+
+func shapeIndex(info *dictInfo, t *types.Type) int {
+	for i, s := range info.shapeParams {
+		if s == t {
+			return i
+		}
+	}
+	base.Fatalf("can't find type %v in shape params", t)
+	return -1
+}
+
+// addMethodExprClosure adds the T.M method expression to the list of bound method expressions
+// used in the generic body.
+// isBoundMethod must have returned true on the same arguments.
+func addMethodExprClosure(info *dictInfo, se *ir.SelectorExpr) {
+	idx := shapeIndex(info, se.X.Type())
+	name := se.Sel.Name
+	for _, b := range info.methodExprClosures {
+		if idx == b.idx && name == b.name {
+			return
+		}
+	}
+	infoPrint("  Method expression closure for %v.%s\n", info.shapeParams[idx], name)
+	info.methodExprClosures = append(info.methodExprClosures, methodExprClosure{idx: idx, name: name})
+}
+
+// findMethodExprClosure finds the entry in the dictionary to use for the T.M
+// method expression encoded in se.
+// isBoundMethod must have returned true on the same arguments.
+func findMethodExprClosure(info *dictInfo, se *ir.SelectorExpr) int {
+	idx := shapeIndex(info, se.X.Type())
+	name := se.Sel.Name
+	for i, b := range info.methodExprClosures {
+		if idx == b.idx && name == b.name {
+			return i
+		}
+	}
+	base.Fatalf("can't find method expression closure for %s %s", se.X.Type(), name)
+	return -1
+}
+
+// addType adds t to info.derivedTypes if it is parameterized type (which is not
+// just a simple shape) that is different from any existing type on
+// info.derivedTypes.
+func addType(info *dictInfo, n ir.Node, t *types.Type) {
+	if t == nil || !t.HasShape() {
+		return
+	}
+	if t.IsShape() {
+		return
+	}
+	if t.Kind() == types.TFUNC && n != nil &&
+		(t.Recv() != nil || n.Op() == ir.ONAME && n.Name().Class == ir.PFUNC) {
+		// Don't use the type of a named generic function or method,
+		// since that is parameterized by other typeparams.
+		// (They all come from arguments of a FUNCINST node.)
+		return
+	}
+	if doubleCheck && !parameterizedBy(t, info.shapeParams) {
+		base.Fatalf("adding type with invalid parameters %+v", t)
+	}
+	if t.Kind() == types.TSTRUCT && t.IsFuncArgStruct() {
+		// Multiple return values are not a relevant new type (?).
+		return
+	}
+	// Ignore a derived type we've already added.
+	for _, et := range info.derivedTypes {
+		if types.IdenticalStrict(t, et) {
+			return
+		}
+	}
+	info.derivedTypes = append(info.derivedTypes, t)
+}
+
+// parameterizedBy returns true if t is parameterized by (at most) params.
+func parameterizedBy(t *types.Type, params []*types.Type) bool {
+	return parameterizedBy1(t, params, map[*types.Type]bool{})
+}
+func parameterizedBy1(t *types.Type, params []*types.Type, visited map[*types.Type]bool) bool {
+	if visited[t] {
+		return true
+	}
+	visited[t] = true
+
+	if t.Sym() != nil && len(t.RParams()) > 0 {
+		// This defined type is instantiated. Check the instantiating types.
+		for _, r := range t.RParams() {
+			if !parameterizedBy1(r, params, visited) {
+				return false
+			}
+		}
+		return true
+	}
+	if t.IsShape() {
+		// Check if t is one of the allowed parameters in scope.
+		for _, p := range params {
+			if p == t {
+				return true
+			}
+		}
+		// Couldn't find t in the list of allowed parameters.
+		return false
+
+	}
+	switch t.Kind() {
+	case types.TARRAY, types.TPTR, types.TSLICE, types.TCHAN:
+		return parameterizedBy1(t.Elem(), params, visited)
+
+	case types.TMAP:
+		return parameterizedBy1(t.Key(), params, visited) && parameterizedBy1(t.Elem(), params, visited)
+
+	case types.TFUNC:
+		return parameterizedBy1(t.TParams(), params, visited) && parameterizedBy1(t.Recvs(), params, visited) && parameterizedBy1(t.Params(), params, visited) && parameterizedBy1(t.Results(), params, visited)
+
+	case types.TSTRUCT:
+		for _, f := range t.Fields().Slice() {
+			if !parameterizedBy1(f.Type, params, visited) {
+				return false
+			}
+		}
+		return true
+
+	case types.TINTER:
+		for _, f := range t.Methods().Slice() {
+			if !parameterizedBy1(f.Type, params, visited) {
+				return false
+			}
+		}
+		return true
+
+	case types.TINT, types.TINT8, types.TINT16, types.TINT32, types.TINT64,
+		types.TUINT, types.TUINT8, types.TUINT16, types.TUINT32, types.TUINT64,
+		types.TUINTPTR, types.TBOOL, types.TSTRING, types.TFLOAT32, types.TFLOAT64, types.TCOMPLEX64, types.TCOMPLEX128, types.TUNSAFEPTR:
+		return true
+
+	case types.TUNION:
+		for i := 0; i < t.NumTerms(); i++ {
+			tt, _ := t.Term(i)
+			if !parameterizedBy1(tt, params, visited) {
+				return false
+			}
+		}
+		return true
+
+	default:
+		base.Fatalf("bad type kind %+v", t)
+		return true
+	}
+}
+
+// startClosure starts creation of a closure that has the function type typ. It
+// creates all the formal params and results according to the type typ. On return,
+// the body and closure variables of the closure must still be filled in, and
+// ir.UseClosure() called.
+func startClosure(pos src.XPos, outer *ir.Func, typ *types.Type) (*ir.Func, []*types.Field, []*types.Field) {
+	// Make a new internal function.
+	fn := ir.NewClosureFunc(pos, outer != nil)
+	ir.NameClosure(fn.OClosure, outer)
+
+	// Build formal argument and return lists.
+	var formalParams []*types.Field  // arguments of closure
+	var formalResults []*types.Field // returns of closure
+	for i := 0; i < typ.NumParams(); i++ {
+		t := typ.Params().Field(i).Type
+		arg := ir.NewNameAt(pos, closureSym(outer, "a", i))
+		arg.Class = ir.PPARAM
+		typed(t, arg)
+		arg.Curfn = fn
+		fn.Dcl = append(fn.Dcl, arg)
+		f := types.NewField(pos, arg.Sym(), t)
+		f.Nname = arg
+		f.SetIsDDD(typ.Params().Field(i).IsDDD())
+		formalParams = append(formalParams, f)
+	}
+	for i := 0; i < typ.NumResults(); i++ {
+		t := typ.Results().Field(i).Type
+		result := ir.NewNameAt(pos, closureSym(outer, "r", i)) // TODO: names not needed?
+		result.Class = ir.PPARAMOUT
+		typed(t, result)
+		result.Curfn = fn
+		fn.Dcl = append(fn.Dcl, result)
+		f := types.NewField(pos, result.Sym(), t)
+		f.Nname = result
+		formalResults = append(formalResults, f)
+	}
+
+	// Build an internal function with the right signature.
+	closureType := types.NewSignature(typ.Pkg(), nil, nil, formalParams, formalResults)
+	typed(closureType, fn.Nname)
+	typed(typ, fn.OClosure)
+	fn.SetTypecheck(1)
+	return fn, formalParams, formalResults
+
+}
+
+// closureSym returns outer.Sym().Pkg.LookupNum(prefix, n).
+// If outer is nil, then types.LocalPkg is used instead.
+func closureSym(outer *ir.Func, prefix string, n int) *types.Sym {
+	pkg := types.LocalPkg
+	if outer != nil {
+		pkg = outer.Sym().Pkg
+	}
+	return pkg.LookupNum(prefix, n)
+}
+
+// assertToBound returns a new node that converts a node rcvr with interface type to
+// the 'dst' interface type.
+func assertToBound(info *instInfo, dictVar *ir.Name, pos src.XPos, rcvr ir.Node, dst *types.Type) ir.Node {
+	if !dst.HasShape() {
+		return typed(dst, ir.NewTypeAssertExpr(pos, rcvr, nil))
+	}
+
+	ix := findDictType(info, dst)
+	assert(ix >= 0)
+	rt := getDictionaryType(info, dictVar, pos, ix)
+	return typed(dst, ir.NewDynamicTypeAssertExpr(pos, ir.ODYNAMICDOTTYPE, rcvr, rt))
+}
diff --git a/src/cmd/compile/internal/noder/stmt.go b/src/cmd/compile/internal/noder/stmt.go
new file mode 100644
index 0000000..a349a7e
--- /dev/null
+++ b/src/cmd/compile/internal/noder/stmt.go
@@ -0,0 +1,353 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/internal/src"
+)
+
+// stmts creates nodes for a slice of statements that form a scope.
+func (g *irgen) stmts(stmts []syntax.Stmt) []ir.Node {
+	var nodes []ir.Node
+	types.Markdcl()
+	for _, stmt := range stmts {
+		switch s := g.stmt(stmt).(type) {
+		case nil: // EmptyStmt
+		case *ir.BlockStmt:
+			nodes = append(nodes, s.List...)
+		default:
+			nodes = append(nodes, s)
+		}
+	}
+	types.Popdcl()
+	return nodes
+}
+
+func (g *irgen) stmt(stmt syntax.Stmt) ir.Node {
+	base.Assert(g.exprStmtOK)
+	switch stmt := stmt.(type) {
+	case nil, *syntax.EmptyStmt:
+		return nil
+	case *syntax.LabeledStmt:
+		return g.labeledStmt(stmt)
+	case *syntax.BlockStmt:
+		return ir.NewBlockStmt(g.pos(stmt), g.blockStmt(stmt))
+	case *syntax.ExprStmt:
+		return wrapname(g.pos(stmt.X), g.expr(stmt.X))
+	case *syntax.SendStmt:
+		n := ir.NewSendStmt(g.pos(stmt), g.expr(stmt.Chan), g.expr(stmt.Value))
+		if !g.delayTransform() {
+			transformSend(n)
+		}
+		n.SetTypecheck(1)
+		return n
+	case *syntax.DeclStmt:
+		if g.topFuncIsGeneric && len(stmt.DeclList) > 0 {
+			if _, ok := stmt.DeclList[0].(*syntax.TypeDecl); ok {
+				// TODO: remove this restriction. See issue 47631.
+				base.ErrorfAt(g.pos(stmt), "type declarations inside generic functions are not currently supported")
+			}
+		}
+		n := ir.NewBlockStmt(g.pos(stmt), nil)
+		g.decls(&n.List, stmt.DeclList)
+		return n
+
+	case *syntax.AssignStmt:
+		if stmt.Op != 0 && stmt.Op != syntax.Def {
+			op := g.op(stmt.Op, binOps[:])
+			var n *ir.AssignOpStmt
+			if stmt.Rhs == nil {
+				n = IncDec(g.pos(stmt), op, g.expr(stmt.Lhs))
+			} else {
+				// Eval rhs before lhs, for compatibility with noder1
+				rhs := g.expr(stmt.Rhs)
+				lhs := g.expr(stmt.Lhs)
+				n = ir.NewAssignOpStmt(g.pos(stmt), op, lhs, rhs)
+			}
+			if !g.delayTransform() {
+				transformAsOp(n)
+			}
+			n.SetTypecheck(1)
+			return n
+		}
+
+		// Eval rhs before lhs, for compatibility with noder1
+		rhs := g.exprList(stmt.Rhs)
+		names, lhs := g.assignList(stmt.Lhs, stmt.Op == syntax.Def)
+
+		if len(lhs) == 1 && len(rhs) == 1 {
+			n := ir.NewAssignStmt(g.pos(stmt), lhs[0], rhs[0])
+			n.Def = initDefn(n, names)
+
+			if !g.delayTransform() {
+				lhs, rhs := []ir.Node{n.X}, []ir.Node{n.Y}
+				transformAssign(n, lhs, rhs)
+				n.X, n.Y = lhs[0], rhs[0]
+			}
+			n.SetTypecheck(1)
+			return n
+		}
+
+		n := ir.NewAssignListStmt(g.pos(stmt), ir.OAS2, lhs, rhs)
+		n.Def = initDefn(n, names)
+		if !g.delayTransform() {
+			transformAssign(n, n.Lhs, n.Rhs)
+		}
+		n.SetTypecheck(1)
+		return n
+
+	case *syntax.BranchStmt:
+		return ir.NewBranchStmt(g.pos(stmt), g.tokOp(int(stmt.Tok), branchOps[:]), g.name(stmt.Label))
+	case *syntax.CallStmt:
+		return ir.NewGoDeferStmt(g.pos(stmt), g.tokOp(int(stmt.Tok), callOps[:]), g.expr(stmt.Call))
+	case *syntax.ReturnStmt:
+		n := ir.NewReturnStmt(g.pos(stmt), g.exprList(stmt.Results))
+		if !g.delayTransform() {
+			transformReturn(n)
+		}
+		n.SetTypecheck(1)
+		return n
+	case *syntax.IfStmt:
+		return g.ifStmt(stmt)
+	case *syntax.ForStmt:
+		return g.forStmt(stmt)
+	case *syntax.SelectStmt:
+		n := g.selectStmt(stmt)
+
+		if !g.delayTransform() {
+			transformSelect(n.(*ir.SelectStmt))
+		}
+		n.SetTypecheck(1)
+		return n
+	case *syntax.SwitchStmt:
+		return g.switchStmt(stmt)
+
+	default:
+		g.unhandled("statement", stmt)
+		panic("unreachable")
+	}
+}
+
+// TODO(mdempsky): Investigate replacing with switch statements or dense arrays.
+
+var branchOps = [...]ir.Op{
+	syntax.Break:       ir.OBREAK,
+	syntax.Continue:    ir.OCONTINUE,
+	syntax.Fallthrough: ir.OFALL,
+	syntax.Goto:        ir.OGOTO,
+}
+
+var callOps = [...]ir.Op{
+	syntax.Defer: ir.ODEFER,
+	syntax.Go:    ir.OGO,
+}
+
+func (g *irgen) tokOp(tok int, ops []ir.Op) ir.Op {
+	// TODO(mdempsky): Validate.
+	return ops[tok]
+}
+
+func (g *irgen) op(op syntax.Operator, ops []ir.Op) ir.Op {
+	// TODO(mdempsky): Validate.
+	return ops[op]
+}
+
+func (g *irgen) assignList(expr syntax.Expr, def bool) ([]*ir.Name, []ir.Node) {
+	if !def {
+		return nil, g.exprList(expr)
+	}
+
+	var exprs []syntax.Expr
+	if list, ok := expr.(*syntax.ListExpr); ok {
+		exprs = list.ElemList
+	} else {
+		exprs = []syntax.Expr{expr}
+	}
+
+	var names []*ir.Name
+	res := make([]ir.Node, len(exprs))
+	for i, expr := range exprs {
+		expr := expr.(*syntax.Name)
+		if expr.Value == "_" {
+			res[i] = ir.BlankNode
+			continue
+		}
+
+		if obj, ok := g.info.Uses[expr]; ok {
+			res[i] = g.obj(obj)
+			continue
+		}
+
+		name, _ := g.def(expr)
+		names = append(names, name)
+		res[i] = name
+	}
+
+	return names, res
+}
+
+// initDefn marks the given names as declared by defn and populates
+// its Init field with ODCL nodes. It then reports whether any names
+// were so declared, which can be used to initialize defn.Def.
+func initDefn(defn ir.InitNode, names []*ir.Name) bool {
+	if len(names) == 0 {
+		return false
+	}
+
+	init := make([]ir.Node, len(names))
+	for i, name := range names {
+		name.Defn = defn
+		init[i] = ir.NewDecl(name.Pos(), ir.ODCL, name)
+	}
+	defn.SetInit(init)
+	return true
+}
+
+func (g *irgen) blockStmt(stmt *syntax.BlockStmt) []ir.Node {
+	return g.stmts(stmt.List)
+}
+
+func (g *irgen) ifStmt(stmt *syntax.IfStmt) ir.Node {
+	init := g.stmt(stmt.Init)
+	n := ir.NewIfStmt(g.pos(stmt), g.expr(stmt.Cond), g.blockStmt(stmt.Then), nil)
+	if stmt.Else != nil {
+		e := g.stmt(stmt.Else)
+		if e.Op() == ir.OBLOCK {
+			e := e.(*ir.BlockStmt)
+			n.Else = e.List
+		} else {
+			n.Else = []ir.Node{e}
+		}
+	}
+	return g.init(init, n)
+}
+
+// unpackTwo returns the first two nodes in list. If list has fewer
+// than 2 nodes, then the missing nodes are replaced with nils.
+func unpackTwo(list []ir.Node) (fst, snd ir.Node) {
+	switch len(list) {
+	case 0:
+		return nil, nil
+	case 1:
+		return list[0], nil
+	default:
+		return list[0], list[1]
+	}
+}
+
+func (g *irgen) forStmt(stmt *syntax.ForStmt) ir.Node {
+	if r, ok := stmt.Init.(*syntax.RangeClause); ok {
+		names, lhs := g.assignList(r.Lhs, r.Def)
+		key, value := unpackTwo(lhs)
+		n := ir.NewRangeStmt(g.pos(r), key, value, g.expr(r.X), g.blockStmt(stmt.Body))
+		n.Def = initDefn(n, names)
+		if key != nil {
+			transformCheckAssign(n, key)
+		}
+		if value != nil {
+			transformCheckAssign(n, value)
+		}
+		return n
+	}
+
+	return ir.NewForStmt(g.pos(stmt), g.stmt(stmt.Init), g.expr(stmt.Cond), g.stmt(stmt.Post), g.blockStmt(stmt.Body))
+}
+
+func (g *irgen) selectStmt(stmt *syntax.SelectStmt) ir.Node {
+	body := make([]*ir.CommClause, len(stmt.Body))
+	for i, clause := range stmt.Body {
+		body[i] = ir.NewCommStmt(g.pos(clause), g.stmt(clause.Comm), g.stmts(clause.Body))
+	}
+	return ir.NewSelectStmt(g.pos(stmt), body)
+}
+
+func (g *irgen) switchStmt(stmt *syntax.SwitchStmt) ir.Node {
+	pos := g.pos(stmt)
+	init := g.stmt(stmt.Init)
+
+	var expr ir.Node
+	switch tag := stmt.Tag.(type) {
+	case *syntax.TypeSwitchGuard:
+		var ident *ir.Ident
+		if tag.Lhs != nil {
+			ident = ir.NewIdent(g.pos(tag.Lhs), g.name(tag.Lhs))
+		}
+		expr = ir.NewTypeSwitchGuard(pos, ident, g.expr(tag.X))
+	default:
+		expr = g.expr(tag)
+	}
+
+	body := make([]*ir.CaseClause, len(stmt.Body))
+	for i, clause := range stmt.Body {
+		// Check for an implicit clause variable before
+		// visiting body, because it may contain function
+		// literals that reference it, and then it'll be
+		// associated to the wrong function.
+		//
+		// Also, override its position to the clause's colon, so that
+		// dwarfgen can find the right scope for it later.
+		// TODO(mdempsky): We should probably just store the scope
+		// directly in the ir.Name.
+		var cv *ir.Name
+		if obj, ok := g.info.Implicits[clause]; ok {
+			cv = g.obj(obj)
+			cv.SetPos(g.makeXPos(clause.Colon))
+			assert(expr.Op() == ir.OTYPESW)
+			cv.Defn = expr
+		}
+		body[i] = ir.NewCaseStmt(g.pos(clause), g.exprList(clause.Cases), g.stmts(clause.Body))
+		body[i].Var = cv
+	}
+
+	return g.init(init, ir.NewSwitchStmt(pos, expr, body))
+}
+
+func (g *irgen) labeledStmt(label *syntax.LabeledStmt) ir.Node {
+	sym := g.name(label.Label)
+	lhs := ir.NewLabelStmt(g.pos(label), sym)
+	ls := g.stmt(label.Stmt)
+
+	// Attach label directly to control statement too.
+	switch ls := ls.(type) {
+	case *ir.ForStmt:
+		ls.Label = sym
+	case *ir.RangeStmt:
+		ls.Label = sym
+	case *ir.SelectStmt:
+		ls.Label = sym
+	case *ir.SwitchStmt:
+		ls.Label = sym
+	}
+
+	l := []ir.Node{lhs}
+	if ls != nil {
+		if ls.Op() == ir.OBLOCK {
+			ls := ls.(*ir.BlockStmt)
+			l = append(l, ls.List...)
+		} else {
+			l = append(l, ls)
+		}
+	}
+	return ir.NewBlockStmt(src.NoXPos, l)
+}
+
+func (g *irgen) init(init ir.Node, stmt ir.InitNode) ir.InitNode {
+	if init != nil {
+		stmt.SetInit([]ir.Node{init})
+	}
+	return stmt
+}
+
+func (g *irgen) name(name *syntax.Name) *types.Sym {
+	if name == nil {
+		return nil
+	}
+	return typecheck.Lookup(name.Value)
+}
diff --git a/src/cmd/compile/internal/noder/transform.go b/src/cmd/compile/internal/noder/transform.go
new file mode 100644
index 0000000..15adb89
--- /dev/null
+++ b/src/cmd/compile/internal/noder/transform.go
@@ -0,0 +1,1085 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains transformation functions on nodes, which are the
+// transformations that the typecheck package does that are distinct from the
+// typechecking functionality. These transform functions are pared-down copies of
+// the original typechecking functions, with all code removed that is related to:
+//
+//    - Detecting compile-time errors (already done by types2)
+//    - Setting the actual type of existing nodes (already done based on
+//      type info from types2)
+//    - Dealing with untyped constants (which types2 has already resolved)
+//
+// Each of the transformation functions requires that node passed in has its type
+// and typecheck flag set. If the transformation function replaces or adds new
+// nodes, it will set the type and typecheck flag for those new nodes.
+
+package noder
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"fmt"
+	"go/constant"
+)
+
+// Transformation functions for expressions
+
+// transformAdd transforms an addition operation (currently just addition of
+// strings). Corresponds to the "binary operators" case in typecheck.typecheck1.
+func transformAdd(n *ir.BinaryExpr) ir.Node {
+	assert(n.Type() != nil && n.Typecheck() == 1)
+	l := n.X
+	if l.Type().IsString() {
+		var add *ir.AddStringExpr
+		if l.Op() == ir.OADDSTR {
+			add = l.(*ir.AddStringExpr)
+			add.SetPos(n.Pos())
+		} else {
+			add = ir.NewAddStringExpr(n.Pos(), []ir.Node{l})
+		}
+		r := n.Y
+		if r.Op() == ir.OADDSTR {
+			r := r.(*ir.AddStringExpr)
+			add.List.Append(r.List.Take()...)
+		} else {
+			add.List.Append(r)
+		}
+		typed(l.Type(), add)
+		return add
+	}
+	return n
+}
+
+// Corresponds to typecheck.stringtoruneslit.
+func stringtoruneslit(n *ir.ConvExpr) ir.Node {
+	if n.X.Op() != ir.OLITERAL || n.X.Val().Kind() != constant.String {
+		base.Fatalf("stringtoarraylit %v", n)
+	}
+
+	var list []ir.Node
+	i := 0
+	eltType := n.Type().Elem()
+	for _, r := range ir.StringVal(n.X) {
+		elt := ir.NewKeyExpr(base.Pos, ir.NewInt(int64(i)), ir.NewInt(int64(r)))
+		// Change from untyped int to the actual element type determined
+		// by types2.  No need to change elt.Key, since the array indexes
+		// are just used for setting up the element ordering.
+		elt.Value.SetType(eltType)
+		list = append(list, elt)
+		i++
+	}
+
+	nn := ir.NewCompLitExpr(base.Pos, ir.OCOMPLIT, n.Type(), list)
+	typed(n.Type(), nn)
+	// Need to transform the OCOMPLIT.
+	return transformCompLit(nn)
+}
+
+// transformConv transforms an OCONV node as needed, based on the types involved,
+// etc.  Corresponds to typecheck.tcConv.
+func transformConv(n *ir.ConvExpr) ir.Node {
+	t := n.X.Type()
+	op, why := typecheck.Convertop(n.X.Op() == ir.OLITERAL, t, n.Type())
+	if op == ir.OXXX {
+		// types2 currently ignores pragmas, so a 'notinheap' mismatch is the
+		// one type-related error that it does not catch. This error will be
+		// caught here by Convertop (see two checks near beginning of
+		// Convertop) and reported at the end of noding.
+		base.ErrorfAt(n.Pos(), "cannot convert %L to type %v%s", n.X, n.Type(), why)
+		return n
+	}
+	n.SetOp(op)
+	switch n.Op() {
+	case ir.OCONVNOP:
+		if t.Kind() == n.Type().Kind() {
+			switch t.Kind() {
+			case types.TFLOAT32, types.TFLOAT64, types.TCOMPLEX64, types.TCOMPLEX128:
+				// Floating point casts imply rounding and
+				// so the conversion must be kept.
+				n.SetOp(ir.OCONV)
+			}
+		}
+
+	// Do not convert to []byte literal. See CL 125796.
+	// Generated code and compiler memory footprint is better without it.
+	case ir.OSTR2BYTES:
+		// ok
+
+	case ir.OSTR2RUNES:
+		if n.X.Op() == ir.OLITERAL {
+			return stringtoruneslit(n)
+		}
+
+	case ir.OBYTES2STR:
+		assert(t.IsSlice())
+		assert(t.Elem().Kind() == types.TUINT8)
+		if t.Elem() != types.ByteType && t.Elem() != types.Types[types.TUINT8] {
+			// If t is a slice of a user-defined byte type B (not uint8
+			// or byte), then add an extra CONVNOP from []B to []byte, so
+			// that the call to slicebytetostring() added in walk will
+			// typecheck correctly.
+			n.X = ir.NewConvExpr(n.X.Pos(), ir.OCONVNOP, types.NewSlice(types.ByteType), n.X)
+			n.X.SetTypecheck(1)
+		}
+
+	case ir.ORUNES2STR:
+		assert(t.IsSlice())
+		assert(t.Elem().Kind() == types.TINT32)
+		if t.Elem() != types.RuneType && t.Elem() != types.Types[types.TINT32] {
+			// If t is a slice of a user-defined rune type B (not uint32
+			// or rune), then add an extra CONVNOP from []B to []rune, so
+			// that the call to slicerunetostring() added in walk will
+			// typecheck correctly.
+			n.X = ir.NewConvExpr(n.X.Pos(), ir.OCONVNOP, types.NewSlice(types.RuneType), n.X)
+			n.X.SetTypecheck(1)
+		}
+
+	}
+	return n
+}
+
+// transformConvCall transforms a conversion call. Corresponds to the OTYPE part of
+// typecheck.tcCall.
+func transformConvCall(n *ir.CallExpr) ir.Node {
+	assert(n.Type() != nil && n.Typecheck() == 1)
+	arg := n.Args[0]
+	n1 := ir.NewConvExpr(n.Pos(), ir.OCONV, nil, arg)
+	typed(n.X.Type(), n1)
+	return transformConv(n1)
+}
+
+// transformCall transforms a normal function/method call. Corresponds to last half
+// (non-conversion, non-builtin part) of typecheck.tcCall. This code should work even
+// in the case of OCALL/OFUNCINST.
+func transformCall(n *ir.CallExpr) {
+	// Set base.Pos, since transformArgs below may need it, but transformCall
+	// is called in some passes that don't set base.Pos.
+	ir.SetPos(n)
+	// n.Type() can be nil for calls with no return value
+	assert(n.Typecheck() == 1)
+	typecheck.RewriteNonNameCall(n)
+	transformArgs(n)
+	l := n.X
+	t := l.Type()
+
+	switch l.Op() {
+	case ir.ODOTINTER:
+		n.SetOp(ir.OCALLINTER)
+
+	case ir.ODOTMETH:
+		l := l.(*ir.SelectorExpr)
+		n.SetOp(ir.OCALLMETH)
+
+		tp := t.Recv().Type
+
+		if l.X == nil || !types.Identical(l.X.Type(), tp) {
+			base.Fatalf("method receiver")
+		}
+
+	default:
+		n.SetOp(ir.OCALLFUNC)
+	}
+
+	typecheckaste(ir.OCALL, n.X, n.IsDDD, t.Params(), n.Args)
+	if l.Op() == ir.ODOTMETH && len(deref(n.X.Type().Recv().Type).RParams()) == 0 {
+		typecheck.FixMethodCall(n)
+	}
+	if t.NumResults() == 1 {
+		if n.Op() == ir.OCALLFUNC && n.X.Op() == ir.ONAME {
+			if sym := n.X.(*ir.Name).Sym(); types.IsRuntimePkg(sym.Pkg) && sym.Name == "getg" {
+				// Emit code for runtime.getg() directly instead of calling function.
+				// Most such rewrites (for example the similar one for math.Sqrt) should be done in walk,
+				// so that the ordering pass can make sure to preserve the semantics of the original code
+				// (in particular, the exact time of the function call) by introducing temporaries.
+				// In this case, we know getg() always returns the same result within a given function
+				// and we want to avoid the temporaries, so we do the rewrite earlier than is typical.
+				n.SetOp(ir.OGETG)
+			}
+		}
+		return
+	}
+}
+
+// transformEarlyCall transforms the arguments of a call with an OFUNCINST node.
+func transformEarlyCall(n *ir.CallExpr) {
+	transformArgs(n)
+	typecheckaste(ir.OCALL, n.X, n.IsDDD, n.X.Type().Params(), n.Args)
+}
+
+// transformCompare transforms a compare operation (currently just equals/not
+// equals). Corresponds to the "comparison operators" case in
+// typecheck.typecheck1, including tcArith.
+func transformCompare(n *ir.BinaryExpr) {
+	assert(n.Type() != nil && n.Typecheck() == 1)
+	if (n.Op() == ir.OEQ || n.Op() == ir.ONE) && !types.Identical(n.X.Type(), n.Y.Type()) {
+		// Comparison is okay as long as one side is assignable to the
+		// other. The only allowed case where the conversion is not CONVNOP is
+		// "concrete == interface". In that case, check comparability of
+		// the concrete type. The conversion allocates, so only do it if
+		// the concrete type is huge.
+		l, r := n.X, n.Y
+		lt, rt := l.Type(), r.Type()
+		converted := false
+		if rt.Kind() != types.TBLANK {
+			aop, _ := typecheck.Assignop(lt, rt)
+			if aop != ir.OXXX {
+				types.CalcSize(lt)
+				if lt.HasShape() || rt.IsInterface() == lt.IsInterface() || lt.Size() >= 1<<16 {
+					l = ir.NewConvExpr(base.Pos, aop, rt, l)
+					l.SetTypecheck(1)
+				}
+
+				converted = true
+			}
+		}
+
+		if !converted && lt.Kind() != types.TBLANK {
+			aop, _ := typecheck.Assignop(rt, lt)
+			if aop != ir.OXXX {
+				types.CalcSize(rt)
+				if rt.HasShape() || rt.IsInterface() == lt.IsInterface() || rt.Size() >= 1<<16 {
+					r = ir.NewConvExpr(base.Pos, aop, lt, r)
+					r.SetTypecheck(1)
+				}
+			}
+		}
+		n.X, n.Y = l, r
+	}
+}
+
+// Corresponds to typecheck.implicitstar.
+func implicitstar(n ir.Node) ir.Node {
+	// insert implicit * if needed for fixed array
+	t := n.Type()
+	if !t.IsPtr() {
+		return n
+	}
+	t = t.Elem()
+	if !t.IsArray() {
+		return n
+	}
+	star := ir.NewStarExpr(base.Pos, n)
+	star.SetImplicit(true)
+	return typed(t, star)
+}
+
+// transformIndex transforms an index operation.  Corresponds to typecheck.tcIndex.
+func transformIndex(n *ir.IndexExpr) {
+	assert(n.Type() != nil && n.Typecheck() == 1)
+	n.X = implicitstar(n.X)
+	l := n.X
+	t := l.Type()
+	if t.Kind() == types.TMAP {
+		n.Index = assignconvfn(n.Index, t.Key())
+		n.SetOp(ir.OINDEXMAP)
+		// Set type to just the map value, not (value, bool). This is
+		// different from types2, but fits the later stages of the
+		// compiler better.
+		n.SetType(t.Elem())
+		n.Assigned = false
+	}
+}
+
+// transformSlice transforms a slice operation.  Corresponds to typecheck.tcSlice.
+func transformSlice(n *ir.SliceExpr) {
+	assert(n.Type() != nil && n.Typecheck() == 1)
+	l := n.X
+	if l.Type().IsArray() {
+		addr := typecheck.NodAddr(n.X)
+		addr.SetImplicit(true)
+		typed(types.NewPtr(n.X.Type()), addr)
+		n.X = addr
+		l = addr
+	}
+	t := l.Type()
+	if t.IsString() {
+		n.SetOp(ir.OSLICESTR)
+	} else if t.IsPtr() && t.Elem().IsArray() {
+		if n.Op().IsSlice3() {
+			n.SetOp(ir.OSLICE3ARR)
+		} else {
+			n.SetOp(ir.OSLICEARR)
+		}
+	}
+}
+
+// Transformation functions for statements
+
+// Corresponds to typecheck.checkassign.
+func transformCheckAssign(stmt ir.Node, n ir.Node) {
+	if n.Op() == ir.OINDEXMAP {
+		n := n.(*ir.IndexExpr)
+		n.Assigned = true
+		return
+	}
+}
+
+// Corresponds to typecheck.assign.
+func transformAssign(stmt ir.Node, lhs, rhs []ir.Node) {
+	checkLHS := func(i int, typ *types.Type) {
+		transformCheckAssign(stmt, lhs[i])
+	}
+
+	cr := len(rhs)
+	if len(rhs) == 1 {
+		if rtyp := rhs[0].Type(); rtyp != nil && rtyp.IsFuncArgStruct() {
+			cr = rtyp.NumFields()
+		}
+	}
+
+	// x, ok = y
+assignOK:
+	for len(lhs) == 2 && cr == 1 {
+		stmt := stmt.(*ir.AssignListStmt)
+		r := rhs[0]
+
+		switch r.Op() {
+		case ir.OINDEXMAP:
+			stmt.SetOp(ir.OAS2MAPR)
+		case ir.ORECV:
+			stmt.SetOp(ir.OAS2RECV)
+		case ir.ODOTTYPE:
+			r := r.(*ir.TypeAssertExpr)
+			stmt.SetOp(ir.OAS2DOTTYPE)
+			r.SetOp(ir.ODOTTYPE2)
+		case ir.ODYNAMICDOTTYPE:
+			r := r.(*ir.DynamicTypeAssertExpr)
+			stmt.SetOp(ir.OAS2DOTTYPE)
+			r.SetOp(ir.ODYNAMICDOTTYPE2)
+		default:
+			break assignOK
+		}
+		checkLHS(0, r.Type())
+		checkLHS(1, types.UntypedBool)
+		t := lhs[0].Type()
+		if t != nil && rhs[0].Type().HasShape() && t.IsInterface() && !types.IdenticalStrict(t, rhs[0].Type()) {
+			// This is a multi-value assignment (map, channel, or dot-type)
+			// where the main result is converted to an interface during the
+			// assignment. Normally, the needed CONVIFACE is not created
+			// until (*orderState).as2ok(), because the AS2* ops and their
+			// sub-ops are so tightly intertwined. But we need to create the
+			// CONVIFACE now to enable dictionary lookups. So, assign the
+			// results first to temps, so that we can manifest the CONVIFACE
+			// in assigning the first temp to lhs[0]. If we added the
+			// CONVIFACE into rhs[0] directly, we would break a lot of later
+			// code that depends on the tight coupling between the AS2* ops
+			// and their sub-ops. (Issue #50642).
+			v := typecheck.Temp(rhs[0].Type())
+			ok := typecheck.Temp(types.Types[types.TBOOL])
+			as := ir.NewAssignListStmt(base.Pos, stmt.Op(), []ir.Node{v, ok}, []ir.Node{r})
+			as.Def = true
+			as.PtrInit().Append(ir.NewDecl(base.Pos, ir.ODCL, v))
+			as.PtrInit().Append(ir.NewDecl(base.Pos, ir.ODCL, ok))
+			as.SetTypecheck(1)
+			// Change stmt to be a normal assignment of the temps to the final
+			// left-hand-sides. We re-create the original multi-value assignment
+			// so that it assigns to the temps and add it as an init of stmt.
+			//
+			// TODO: fix the order of evaluation, so that the lval of lhs[0]
+			// is evaluated before rhs[0] (similar to problem in #50672).
+			stmt.SetOp(ir.OAS2)
+			stmt.PtrInit().Append(as)
+			// assignconvfn inserts the CONVIFACE.
+			stmt.Rhs = []ir.Node{assignconvfn(v, t), ok}
+		}
+		return
+	}
+
+	if len(lhs) != cr {
+		for i := range lhs {
+			checkLHS(i, nil)
+		}
+		return
+	}
+
+	// x,y,z = f()
+	if cr > len(rhs) {
+		stmt := stmt.(*ir.AssignListStmt)
+		stmt.SetOp(ir.OAS2FUNC)
+		r := rhs[0].(*ir.CallExpr)
+		rtyp := r.Type()
+
+		mismatched := false
+		failed := false
+		for i := range lhs {
+			result := rtyp.Field(i).Type
+			checkLHS(i, result)
+
+			if lhs[i].Type() == nil || result == nil {
+				failed = true
+			} else if lhs[i] != ir.BlankNode && !types.Identical(lhs[i].Type(), result) {
+				mismatched = true
+			}
+		}
+		if mismatched && !failed {
+			typecheck.RewriteMultiValueCall(stmt, r)
+		}
+		return
+	}
+
+	for i, r := range rhs {
+		checkLHS(i, r.Type())
+		if lhs[i].Type() != nil {
+			rhs[i] = assignconvfn(r, lhs[i].Type())
+		}
+	}
+}
+
+// Corresponds to typecheck.typecheckargs.  Really just deals with multi-value calls.
+func transformArgs(n ir.InitNode) {
+	var list []ir.Node
+	switch n := n.(type) {
+	default:
+		base.Fatalf("transformArgs %+v", n.Op())
+	case *ir.CallExpr:
+		list = n.Args
+		if n.IsDDD {
+			return
+		}
+	case *ir.ReturnStmt:
+		list = n.Results
+	}
+	if len(list) != 1 {
+		return
+	}
+
+	t := list[0].Type()
+	if t == nil || !t.IsFuncArgStruct() {
+		return
+	}
+
+	// Save n as n.Orig for fmt.go.
+	if ir.Orig(n) == n {
+		n.(ir.OrigNode).SetOrig(ir.SepCopy(n))
+	}
+
+	// Rewrite f(g()) into t1, t2, ... = g(); f(t1, t2, ...).
+	typecheck.RewriteMultiValueCall(n, list[0])
+}
+
+// assignconvfn converts node n for assignment to type t. Corresponds to
+// typecheck.assignconvfn.
+func assignconvfn(n ir.Node, t *types.Type) ir.Node {
+	if t.Kind() == types.TBLANK {
+		return n
+	}
+
+	if n.Op() == ir.OPAREN {
+		n = n.(*ir.ParenExpr).X
+	}
+
+	if types.IdenticalStrict(n.Type(), t) {
+		return n
+	}
+
+	op, why := Assignop(n.Type(), t)
+	if op == ir.OXXX {
+		base.Fatalf("found illegal assignment %+v -> %+v; %s", n.Type(), t, why)
+	}
+
+	r := ir.NewConvExpr(base.Pos, op, t, n)
+	r.SetTypecheck(1)
+	r.SetImplicit(true)
+	return r
+}
+
+func Assignop(src, dst *types.Type) (ir.Op, string) {
+	if src == dst {
+		return ir.OCONVNOP, ""
+	}
+	if src == nil || dst == nil || src.Kind() == types.TFORW || dst.Kind() == types.TFORW || src.Underlying() == nil || dst.Underlying() == nil {
+		return ir.OXXX, ""
+	}
+
+	// 1. src type is identical to dst (taking shapes into account)
+	if types.Identical(src, dst) {
+		// We already know from assignconvfn above that IdenticalStrict(src,
+		// dst) is false, so the types are not exactly the same and one of
+		// src or dst is a shape. If dst is an interface (which means src is
+		// an interface too), we need a real OCONVIFACE op; otherwise we need a
+		// OCONVNOP. See issue #48453.
+		if dst.IsInterface() {
+			return ir.OCONVIFACE, ""
+		} else {
+			return ir.OCONVNOP, ""
+		}
+	}
+	return typecheck.Assignop1(src, dst)
+}
+
+// Corresponds to typecheck.typecheckaste, but we add an extra flag convifaceOnly
+// only. If convifaceOnly is true, we only do interface conversion. We use this to do
+// early insertion of CONVIFACE nodes during noder2, when the function or args may
+// have typeparams.
+func typecheckaste(op ir.Op, call ir.Node, isddd bool, tstruct *types.Type, nl ir.Nodes) {
+	var t *types.Type
+	var i int
+
+	lno := base.Pos
+	defer func() { base.Pos = lno }()
+
+	var n ir.Node
+	if len(nl) == 1 {
+		n = nl[0]
+	}
+
+	i = 0
+	for _, tl := range tstruct.Fields().Slice() {
+		t = tl.Type
+		if tl.IsDDD() {
+			if isddd {
+				n = nl[i]
+				ir.SetPos(n)
+				if n.Type() != nil {
+					nl[i] = assignconvfn(n, t)
+				}
+				return
+			}
+
+			// TODO(mdempsky): Make into ... call with implicit slice.
+			for ; i < len(nl); i++ {
+				n = nl[i]
+				ir.SetPos(n)
+				if n.Type() != nil {
+					nl[i] = assignconvfn(n, t.Elem())
+				}
+			}
+			return
+		}
+
+		n = nl[i]
+		ir.SetPos(n)
+		if n.Type() != nil {
+			nl[i] = assignconvfn(n, t)
+		}
+		i++
+	}
+}
+
+// transformSend transforms a send statement, converting the value to appropriate
+// type for the channel, as needed. Corresponds of typecheck.tcSend.
+func transformSend(n *ir.SendStmt) {
+	n.Value = assignconvfn(n.Value, n.Chan.Type().Elem())
+}
+
+// transformReturn transforms a return node, by doing the needed assignments and
+// any necessary conversions. Corresponds to typecheck.tcReturn()
+func transformReturn(rs *ir.ReturnStmt) {
+	transformArgs(rs)
+	nl := rs.Results
+	if ir.HasNamedResults(ir.CurFunc) && len(nl) == 0 {
+		return
+	}
+
+	typecheckaste(ir.ORETURN, nil, false, ir.CurFunc.Type().Results(), nl)
+}
+
+// transformSelect transforms a select node, creating an assignment list as needed
+// for each case. Corresponds to typecheck.tcSelect().
+func transformSelect(sel *ir.SelectStmt) {
+	for _, ncase := range sel.Cases {
+		if ncase.Comm != nil {
+			n := ncase.Comm
+			oselrecv2 := func(dst, recv ir.Node, def bool) {
+				selrecv := ir.NewAssignListStmt(n.Pos(), ir.OSELRECV2, []ir.Node{dst, ir.BlankNode}, []ir.Node{recv})
+				if dst.Op() == ir.ONAME && dst.(*ir.Name).Defn == n {
+					// Must fix Defn for dst, since we are
+					// completely changing the node.
+					dst.(*ir.Name).Defn = selrecv
+				}
+				selrecv.Def = def
+				selrecv.SetTypecheck(1)
+				selrecv.SetInit(n.Init())
+				ncase.Comm = selrecv
+			}
+			switch n.Op() {
+			case ir.OAS:
+				// convert x = <-c into x, _ = <-c
+				// remove implicit conversions; the eventual assignment
+				// will reintroduce them.
+				n := n.(*ir.AssignStmt)
+				if r := n.Y; r.Op() == ir.OCONVNOP || r.Op() == ir.OCONVIFACE {
+					r := r.(*ir.ConvExpr)
+					if r.Implicit() {
+						n.Y = r.X
+					}
+				}
+				oselrecv2(n.X, n.Y, n.Def)
+
+			case ir.OAS2RECV:
+				n := n.(*ir.AssignListStmt)
+				n.SetOp(ir.OSELRECV2)
+
+			case ir.ORECV:
+				// convert <-c into _, _ = <-c
+				n := n.(*ir.UnaryExpr)
+				oselrecv2(ir.BlankNode, n, false)
+
+			case ir.OSEND:
+				break
+			}
+		}
+	}
+}
+
+// transformAsOp transforms an AssignOp statement. Corresponds to OASOP case in
+// typecheck1.
+func transformAsOp(n *ir.AssignOpStmt) {
+	transformCheckAssign(n, n.X)
+}
+
+// transformDot transforms an OXDOT (or ODOT) or ODOT, ODOTPTR, ODOTMETH,
+// ODOTINTER, or OMETHVALUE, as appropriate. It adds in extra nodes as needed to
+// access embedded fields. Corresponds to typecheck.tcDot.
+func transformDot(n *ir.SelectorExpr, isCall bool) ir.Node {
+	assert(n.Type() != nil && n.Typecheck() == 1)
+	if n.Op() == ir.OXDOT {
+		n = typecheck.AddImplicitDots(n)
+		n.SetOp(ir.ODOT)
+
+		// Set the Selection field and typecheck flag for any new ODOT nodes
+		// added by AddImplicitDots(), and also transform to ODOTPTR if
+		// needed. Equivalent to 'n.X = typecheck(n.X, ctxExpr|ctxType)' in
+		// tcDot.
+		for n1 := n; n1.X.Op() == ir.ODOT; {
+			n1 = n1.X.(*ir.SelectorExpr)
+			if !n1.Implicit() {
+				break
+			}
+			t1 := n1.X.Type()
+			if t1.IsPtr() && !t1.Elem().IsInterface() {
+				t1 = t1.Elem()
+				n1.SetOp(ir.ODOTPTR)
+			}
+			typecheck.Lookdot(n1, t1, 0)
+			n1.SetTypecheck(1)
+		}
+	}
+
+	t := n.X.Type()
+
+	if n.X.Op() == ir.OTYPE {
+		return transformMethodExpr(n)
+	}
+
+	if t.IsPtr() && !t.Elem().IsInterface() {
+		t = t.Elem()
+		n.SetOp(ir.ODOTPTR)
+	}
+
+	f := typecheck.Lookdot(n, t, 0)
+	assert(f != nil)
+
+	if (n.Op() == ir.ODOTINTER || n.Op() == ir.ODOTMETH) && !isCall {
+		n.SetOp(ir.OMETHVALUE)
+		// This converts a method type to a function type. See issue 47775.
+		n.SetType(typecheck.NewMethodType(n.Type(), nil))
+	}
+	return n
+}
+
+// Corresponds to typecheck.typecheckMethodExpr.
+func transformMethodExpr(n *ir.SelectorExpr) (res ir.Node) {
+	t := n.X.Type()
+
+	// Compute the method set for t.
+	var ms *types.Fields
+	if t.IsInterface() {
+		ms = t.AllMethods()
+	} else {
+		mt := types.ReceiverBaseType(t)
+		typecheck.CalcMethods(mt)
+		ms = mt.AllMethods()
+
+		// The method expression T.m requires a wrapper when T
+		// is different from m's declared receiver type. We
+		// normally generate these wrappers while writing out
+		// runtime type descriptors, which is always done for
+		// types declared at package scope. However, we need
+		// to make sure to generate wrappers for anonymous
+		// receiver types too.
+		if mt.Sym() == nil {
+			typecheck.NeedRuntimeType(t)
+		}
+	}
+
+	s := n.Sel
+	m := typecheck.Lookdot1(n, s, t, ms, 0)
+	if !t.HasShape() {
+		// It's OK to not find the method if t is instantiated by shape types,
+		// because we will use the methods on the generic type anyway.
+		assert(m != nil)
+	}
+
+	n.SetOp(ir.OMETHEXPR)
+	n.Selection = m
+	n.SetType(typecheck.NewMethodType(m.Type, n.X.Type()))
+	return n
+}
+
+// Corresponds to typecheck.tcAppend.
+func transformAppend(n *ir.CallExpr) ir.Node {
+	transformArgs(n)
+	args := n.Args
+	t := args[0].Type()
+	assert(t.IsSlice())
+
+	if n.IsDDD {
+		// assignconvfn is of args[1] not required here, as the
+		// types of args[0] and args[1] don't need to match
+		// (They will both have an underlying type which are
+		// slices of identical base types, or be []byte and string.)
+		// See issue 53888.
+		return n
+	}
+
+	as := args[1:]
+	for i, n := range as {
+		assert(n.Type() != nil)
+		as[i] = assignconvfn(n, t.Elem())
+	}
+	return n
+}
+
+// Corresponds to typecheck.tcComplex.
+func transformComplex(n *ir.BinaryExpr) ir.Node {
+	l := n.X
+	r := n.Y
+
+	assert(types.Identical(l.Type(), r.Type()))
+
+	var t *types.Type
+	switch l.Type().Kind() {
+	case types.TFLOAT32:
+		t = types.Types[types.TCOMPLEX64]
+	case types.TFLOAT64:
+		t = types.Types[types.TCOMPLEX128]
+	default:
+		panic(fmt.Sprintf("transformComplex: unexpected type %v", l.Type()))
+	}
+
+	// Must set the type here for generics, because this can't be determined
+	// by substitution of the generic types.
+	typed(t, n)
+	return n
+}
+
+// Corresponds to typecheck.tcDelete.
+func transformDelete(n *ir.CallExpr) ir.Node {
+	transformArgs(n)
+	args := n.Args
+	assert(len(args) == 2)
+
+	l := args[0]
+	r := args[1]
+
+	args[1] = assignconvfn(r, l.Type().Key())
+	return n
+}
+
+// Corresponds to typecheck.tcMake.
+func transformMake(n *ir.CallExpr) ir.Node {
+	args := n.Args
+
+	n.Args = nil
+	l := args[0]
+	t := l.Type()
+	assert(t != nil)
+
+	i := 1
+	var nn ir.Node
+	switch t.Kind() {
+	case types.TSLICE:
+		l = args[i]
+		i++
+		var r ir.Node
+		if i < len(args) {
+			r = args[i]
+			i++
+		}
+		nn = ir.NewMakeExpr(n.Pos(), ir.OMAKESLICE, l, r)
+
+	case types.TMAP:
+		if i < len(args) {
+			l = args[i]
+			i++
+		} else {
+			l = ir.NewInt(0)
+		}
+		nn = ir.NewMakeExpr(n.Pos(), ir.OMAKEMAP, l, nil)
+		nn.SetEsc(n.Esc())
+
+	case types.TCHAN:
+		l = nil
+		if i < len(args) {
+			l = args[i]
+			i++
+		} else {
+			l = ir.NewInt(0)
+		}
+		nn = ir.NewMakeExpr(n.Pos(), ir.OMAKECHAN, l, nil)
+	default:
+		panic(fmt.Sprintf("transformMake: unexpected type %v", t))
+	}
+
+	assert(i == len(args))
+	typed(n.Type(), nn)
+	return nn
+}
+
+// Corresponds to typecheck.tcPanic.
+func transformPanic(n *ir.UnaryExpr) ir.Node {
+	n.X = assignconvfn(n.X, types.Types[types.TINTER])
+	return n
+}
+
+// Corresponds to typecheck.tcPrint.
+func transformPrint(n *ir.CallExpr) ir.Node {
+	transformArgs(n)
+	return n
+}
+
+// Corresponds to typecheck.tcRealImag.
+func transformRealImag(n *ir.UnaryExpr) ir.Node {
+	l := n.X
+	var t *types.Type
+
+	// Determine result type.
+	switch l.Type().Kind() {
+	case types.TCOMPLEX64:
+		t = types.Types[types.TFLOAT32]
+	case types.TCOMPLEX128:
+		t = types.Types[types.TFLOAT64]
+	default:
+		panic(fmt.Sprintf("transformRealImag: unexpected type %v", l.Type()))
+	}
+
+	// Must set the type here for generics, because this can't be determined
+	// by substitution of the generic types.
+	typed(t, n)
+	return n
+}
+
+// Corresponds to typecheck.tcLenCap.
+func transformLenCap(n *ir.UnaryExpr) ir.Node {
+	n.X = implicitstar(n.X)
+	return n
+}
+
+// Corresponds to Builtin part of tcCall.
+func transformBuiltin(n *ir.CallExpr) ir.Node {
+	// n.Type() can be nil for builtins with no return value
+	assert(n.Typecheck() == 1)
+	fun := n.X.(*ir.Name)
+	op := fun.BuiltinOp
+
+	switch op {
+	case ir.OAPPEND, ir.ODELETE, ir.OMAKE, ir.OPRINT, ir.OPRINTN, ir.ORECOVER:
+		n.SetOp(op)
+		n.X = nil
+		switch op {
+		case ir.OAPPEND:
+			return transformAppend(n)
+		case ir.ODELETE:
+			return transformDelete(n)
+		case ir.OMAKE:
+			return transformMake(n)
+		case ir.OPRINT, ir.OPRINTN:
+			return transformPrint(n)
+		case ir.ORECOVER:
+			// nothing more to do
+			return n
+		}
+
+	case ir.OCAP, ir.OCLOSE, ir.OIMAG, ir.OLEN, ir.OPANIC, ir.OREAL:
+		transformArgs(n)
+		fallthrough
+
+	case ir.ONEW, ir.OALIGNOF, ir.OOFFSETOF, ir.OSIZEOF, ir.OUNSAFESLICEDATA, ir.OUNSAFESTRINGDATA:
+		u := ir.NewUnaryExpr(n.Pos(), op, n.Args[0])
+		u1 := typed(n.Type(), ir.InitExpr(n.Init(), u)) // typecheckargs can add to old.Init
+		switch op {
+		case ir.OCAP, ir.OLEN:
+			return transformLenCap(u1.(*ir.UnaryExpr))
+		case ir.OREAL, ir.OIMAG:
+			return transformRealImag(u1.(*ir.UnaryExpr))
+		case ir.OPANIC:
+			return transformPanic(u1.(*ir.UnaryExpr))
+		case ir.OALIGNOF, ir.OOFFSETOF, ir.OSIZEOF:
+			// This corresponds to the EvalConst() call near end of typecheck().
+			return typecheck.EvalConst(u1)
+		case ir.OCLOSE, ir.ONEW, ir.OUNSAFESTRINGDATA, ir.OUNSAFESLICEDATA:
+			// nothing more to do
+			return u1
+		}
+
+	case ir.OCOMPLEX, ir.OCOPY, ir.OUNSAFEADD, ir.OUNSAFESLICE, ir.OUNSAFESTRING:
+		transformArgs(n)
+		b := ir.NewBinaryExpr(n.Pos(), op, n.Args[0], n.Args[1])
+		n1 := typed(n.Type(), ir.InitExpr(n.Init(), b))
+		if op != ir.OCOMPLEX {
+			// nothing more to do
+			return n1
+		}
+		return transformComplex(n1.(*ir.BinaryExpr))
+
+	default:
+		panic(fmt.Sprintf("transformBuiltin: unexpected op %v", op))
+	}
+
+	return n
+}
+
+func hasKeys(l ir.Nodes) bool {
+	for _, n := range l {
+		if n.Op() == ir.OKEY || n.Op() == ir.OSTRUCTKEY {
+			return true
+		}
+	}
+	return false
+}
+
+// transformArrayLit runs assignconvfn on each array element and returns the
+// length of the slice/array that is needed to hold all the array keys/indexes
+// (one more than the highest index). Corresponds to typecheck.typecheckarraylit.
+func transformArrayLit(elemType *types.Type, bound int64, elts []ir.Node) int64 {
+	var key, length int64
+	for i, elt := range elts {
+		ir.SetPos(elt)
+		r := elts[i]
+		var kv *ir.KeyExpr
+		if elt.Op() == ir.OKEY {
+			elt := elt.(*ir.KeyExpr)
+			key = typecheck.IndexConst(elt.Key)
+			assert(key >= 0)
+			kv = elt
+			r = elt.Value
+		}
+
+		r = assignconvfn(r, elemType)
+		if kv != nil {
+			kv.Value = r
+		} else {
+			elts[i] = r
+		}
+
+		key++
+		if key > length {
+			length = key
+		}
+	}
+
+	return length
+}
+
+// transformCompLit transforms n to an OARRAYLIT, OSLICELIT, OMAPLIT, or
+// OSTRUCTLIT node, with any needed conversions. Corresponds to
+// typecheck.tcCompLit (and includes parts corresponding to tcStructLitKey).
+func transformCompLit(n *ir.CompLitExpr) (res ir.Node) {
+	assert(n.Type() != nil && n.Typecheck() == 1)
+	lno := base.Pos
+	defer func() {
+		base.Pos = lno
+	}()
+
+	// Save original node (including n.Right)
+	n.SetOrig(ir.Copy(n))
+
+	ir.SetPos(n)
+
+	t := n.Type()
+
+	switch t.Kind() {
+	default:
+		base.Fatalf("transformCompLit %v", t.Kind())
+
+	case types.TARRAY:
+		transformArrayLit(t.Elem(), t.NumElem(), n.List)
+		n.SetOp(ir.OARRAYLIT)
+
+	case types.TSLICE:
+		length := transformArrayLit(t.Elem(), -1, n.List)
+		n.SetOp(ir.OSLICELIT)
+		n.Len = length
+
+	case types.TMAP:
+		for _, l := range n.List {
+			ir.SetPos(l)
+			assert(l.Op() == ir.OKEY)
+			l := l.(*ir.KeyExpr)
+
+			r := l.Key
+			l.Key = assignconvfn(r, t.Key())
+
+			r = l.Value
+			l.Value = assignconvfn(r, t.Elem())
+		}
+
+		n.SetOp(ir.OMAPLIT)
+
+	case types.TSTRUCT:
+		// Need valid field offsets for Xoffset below.
+		types.CalcSize(t)
+
+		if len(n.List) != 0 && !hasKeys(n.List) {
+			// simple list of values
+			ls := n.List
+			for i, n1 := range ls {
+				ir.SetPos(n1)
+
+				f := t.Field(i)
+				n1 = assignconvfn(n1, f.Type)
+				ls[i] = ir.NewStructKeyExpr(base.Pos, f, n1)
+			}
+			assert(len(ls) >= t.NumFields())
+		} else {
+			// keyed list
+			ls := n.List
+			for i, l := range ls {
+				ir.SetPos(l)
+
+				kv := l.(*ir.KeyExpr)
+				key := kv.Key
+
+				s := key.Sym()
+				if types.IsExported(s.Name) && s.Pkg != types.LocalPkg {
+					// Exported field names should always have
+					// local pkg. We only need to do this
+					// adjustment for generic functions that are
+					// being transformed after being imported
+					// from another package.
+					s = typecheck.Lookup(s.Name)
+				}
+
+				// An OXDOT uses the Sym field to hold
+				// the field to the right of the dot,
+				// so s will be non-nil, but an OXDOT
+				// is never a valid struct literal key.
+				assert(!(s == nil || key.Op() == ir.OXDOT || s.IsBlank()))
+
+				f := typecheck.Lookdot1(nil, s, t, t.Fields(), 0)
+				l := ir.NewStructKeyExpr(l.Pos(), f, kv.Value)
+				ls[i] = l
+
+				l.Value = assignconvfn(l.Value, f.Type)
+			}
+		}
+
+		n.SetOp(ir.OSTRUCTLIT)
+	}
+
+	return n
+}
+
+// transformAddr corresponds to typecheck.tcAddr.
+func transformAddr(n *ir.AddrExpr) {
+	switch n.X.Op() {
+	case ir.OARRAYLIT, ir.OMAPLIT, ir.OSLICELIT, ir.OSTRUCTLIT:
+		n.SetOp(ir.OPTRLIT)
+	}
+}
diff --git a/src/cmd/compile/internal/noder/types.go b/src/cmd/compile/internal/noder/types.go
new file mode 100644
index 0000000..57b35e6
--- /dev/null
+++ b/src/cmd/compile/internal/noder/types.go
@@ -0,0 +1,516 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+	"cmd/internal/src"
+	"strings"
+)
+
+func (g *irgen) pkg(pkg *types2.Package) *types.Pkg {
+	switch pkg {
+	case nil:
+		return types.BuiltinPkg
+	case g.self:
+		return types.LocalPkg
+	case types2.Unsafe:
+		return types.UnsafePkg
+	}
+	return types.NewPkg(pkg.Path(), pkg.Name())
+}
+
+var universeAny = types2.Universe.Lookup("any").Type()
+
+// typ converts a types2.Type to a types.Type, including caching of previously
+// translated types.
+func (g *irgen) typ(typ types2.Type) *types.Type {
+	// Defer the CheckSize calls until we have fully-defined a
+	// (possibly-recursive) top-level type.
+	types.DeferCheckSize()
+	res := g.typ1(typ)
+	types.ResumeCheckSize()
+
+	// Finish up any types on typesToFinalize, now that we are at the top of a
+	// fully-defined (possibly recursive) type. fillinMethods could create more
+	// types to finalize.
+	for len(g.typesToFinalize) > 0 {
+		l := len(g.typesToFinalize)
+		info := g.typesToFinalize[l-1]
+		g.typesToFinalize = g.typesToFinalize[:l-1]
+		types.DeferCheckSize()
+		g.fillinMethods(info.typ, info.ntyp)
+		types.ResumeCheckSize()
+	}
+	return res
+}
+
+// typ1 is like typ, but doesn't call CheckSize, since it may have only
+// constructed part of a recursive type. Should not be called from outside this
+// file (g.typ is the "external" entry point).
+func (g *irgen) typ1(typ types2.Type) *types.Type {
+	// See issue 49583: the type checker has trouble keeping track of aliases,
+	// but for such a common alias as any we can improve things by preserving a
+	// pointer identity that can be checked when formatting type strings.
+	if typ == universeAny {
+		return types.AnyType
+	}
+	// Cache type2-to-type mappings. Important so that each defined generic
+	// type (instantiated or not) has a single types.Type representation.
+	// Also saves a lot of computation and memory by avoiding re-translating
+	// types2 types repeatedly.
+	res, ok := g.typs[typ]
+	if !ok {
+		res = g.typ0(typ)
+		// Calculate the size for all concrete types seen by the frontend.
+		// This is the replacement for the CheckSize() calls in the types1
+		// typechecker. These will be deferred until the top-level g.typ().
+		if res != nil && !res.IsUntyped() && !res.IsFuncArgStruct() && !res.HasTParam() {
+			types.CheckSize(res)
+		}
+		g.typs[typ] = res
+	}
+	return res
+}
+
+// instTypeName2 creates a name for an instantiated type, base on the type args
+// (given as types2 types).
+func (g *irgen) instTypeName2(name string, targs *types2.TypeList) string {
+	rparams := make([]*types.Type, targs.Len())
+	for i := range rparams {
+		rparams[i] = g.typ(targs.At(i))
+	}
+	return typecheck.InstTypeName(name, rparams)
+}
+
+// typ0 converts a types2.Type to a types.Type, but doesn't do the caching check
+// at the top level.
+func (g *irgen) typ0(typ types2.Type) *types.Type {
+	switch typ := typ.(type) {
+	case *types2.Basic:
+		return g.basic(typ)
+	case *types2.Named:
+		// If tparams is set, but targs is not, typ is a base generic
+		// type. typ is appearing as part of the source type of an alias,
+		// since that is the only use of a generic type that doesn't
+		// involve instantiation. We just translate the named type in the
+		// normal way below using g.obj().
+		if typ.TypeParams() != nil && typ.TypeArgs() != nil {
+			// typ is an instantiation of a defined (named) generic type.
+			// This instantiation should also be a defined (named) type.
+			// types2 gives us the substituted type in t.Underlying()
+			// The substituted type may or may not still have type
+			// params. We might, for example, be substituting one type
+			// param for another type param.
+			//
+			// When converted to types.Type, typ has a unique name,
+			// based on the names of the type arguments.
+			instName := g.instTypeName2(typ.Obj().Name(), typ.TypeArgs())
+			s := g.pkg(typ.Obj().Pkg()).Lookup(instName)
+
+			// Make sure the base generic type exists in type1 (it may
+			// not yet if we are referecing an imported generic type, as
+			// opposed to a generic type declared in this package). Make
+			// sure to do this lookup before checking s.Def, in case
+			// s.Def gets defined while importing base (if an imported
+			// type). (Issue #50486).
+			base := g.obj(typ.Origin().Obj())
+
+			if s.Def != nil {
+				// We have already encountered this instantiation.
+				// Use the type we previously created, since there
+				// must be exactly one instance of a defined type.
+				return s.Def.Type()
+			}
+
+			if base.Class == ir.PAUTO {
+				// If the base type is a local type, we want to pop
+				// this instantiated type symbol/definition when we
+				// leave the containing block, so we don't use it
+				// incorrectly later.
+				types.Pushdcl(s)
+			}
+
+			// Create a forwarding type first and put it in the g.typs
+			// map, in order to deal with recursive generic types
+			// (including via method signatures). Set up the extra
+			// ntyp information (Def, RParams, which may set
+			// HasTParam) before translating the underlying type
+			// itself, so we handle recursion correctly.
+			ntyp := typecheck.NewIncompleteNamedType(g.pos(typ.Obj().Pos()), s)
+			g.typs[typ] = ntyp
+
+			// If ntyp still has type params, then we must be
+			// referencing something like 'value[T2]', as when
+			// specifying the generic receiver of a method, where
+			// value was defined as "type value[T any] ...". Save the
+			// type args, which will now be the new typeparams of the
+			// current type.
+			//
+			// If ntyp does not have type params, we are saving the
+			// non-generic types used to instantiate this type. We'll
+			// use these when instantiating the methods of the
+			// instantiated type.
+			targs := typ.TypeArgs()
+			rparams := make([]*types.Type, targs.Len())
+			for i := range rparams {
+				rparams[i] = g.typ1(targs.At(i))
+			}
+			ntyp.SetRParams(rparams)
+			//fmt.Printf("Saw new type %v %v\n", instName, ntyp.HasTParam())
+
+			// Save the symbol for the base generic type.
+			ntyp.SetOrigType(base.Type())
+			ntyp.SetUnderlying(g.typ1(typ.Underlying()))
+			if typ.NumMethods() != 0 {
+				// Save a delayed call to g.fillinMethods() (once
+				// potentially recursive types have been fully
+				// resolved).
+				g.typesToFinalize = append(g.typesToFinalize,
+					&typeDelayInfo{
+						typ:  typ,
+						ntyp: ntyp,
+					})
+			}
+			return ntyp
+		}
+		obj := g.obj(typ.Obj())
+		if obj.Op() != ir.OTYPE {
+			base.FatalfAt(obj.Pos(), "expected type: %L", obj)
+		}
+		return obj.Type()
+
+	case *types2.Array:
+		return types.NewArray(g.typ1(typ.Elem()), typ.Len())
+	case *types2.Chan:
+		return types.NewChan(g.typ1(typ.Elem()), dirs[typ.Dir()])
+	case *types2.Map:
+		return types.NewMap(g.typ1(typ.Key()), g.typ1(typ.Elem()))
+	case *types2.Pointer:
+		return types.NewPtr(g.typ1(typ.Elem()))
+	case *types2.Signature:
+		return g.signature(nil, typ)
+	case *types2.Slice:
+		return types.NewSlice(g.typ1(typ.Elem()))
+
+	case *types2.Struct:
+		fields := make([]*types.Field, typ.NumFields())
+		for i := range fields {
+			v := typ.Field(i)
+			f := types.NewField(g.pos(v), g.selector(v), g.typ1(v.Type()))
+			f.Note = typ.Tag(i)
+			if v.Embedded() {
+				f.Embedded = 1
+			}
+			fields[i] = f
+		}
+		return types.NewStruct(g.tpkg(typ), fields)
+
+	case *types2.Interface:
+		embeddeds := make([]*types.Field, typ.NumEmbeddeds())
+		j := 0
+		for i := range embeddeds {
+			// TODO(mdempsky): Get embedding position.
+			e := typ.EmbeddedType(i)
+
+			// With Go 1.18, an embedded element can be any type, not
+			// just an interface.
+			embeddeds[j] = types.NewField(src.NoXPos, nil, g.typ1(e))
+			j++
+		}
+		embeddeds = embeddeds[:j]
+
+		methods := make([]*types.Field, typ.NumExplicitMethods())
+		for i := range methods {
+			m := typ.ExplicitMethod(i)
+			mtyp := g.signature(types.FakeRecv(), m.Type().(*types2.Signature))
+			methods[i] = types.NewField(g.pos(m), g.selector(m), mtyp)
+		}
+
+		return types.NewInterface(g.tpkg(typ), append(embeddeds, methods...), typ.IsImplicit())
+
+	case *types2.TypeParam:
+		// Save the name of the type parameter in the sym of the type.
+		// Include the types2 subscript in the sym name
+		pkg := g.tpkg(typ)
+		// Create the unique types1 name for a type param, using its context
+		// with a function, type, or method declaration. Also, map blank type
+		// param names to a unique name based on their type param index. The
+		// unique blank names will be exported, but will be reverted during
+		// types2 and gcimporter import.
+		assert(g.curDecl != "")
+		nm := typecheck.TparamExportName(g.curDecl, typ.Obj().Name(), typ.Index())
+		sym := pkg.Lookup(nm)
+		if sym.Def != nil {
+			// Make sure we use the same type param type for the same
+			// name, whether it is created during types1-import or
+			// this types2-to-types1 translation.
+			return sym.Def.Type()
+		}
+		obj := ir.NewDeclNameAt(g.pos(typ.Obj().Pos()), ir.OTYPE, sym)
+		sym.Def = obj
+		tp := types.NewTypeParam(obj, typ.Index())
+		obj.SetType(tp)
+		// Set g.typs[typ] in case the bound methods reference typ.
+		g.typs[typ] = tp
+
+		bound := g.typ1(typ.Constraint())
+		tp.SetBound(bound)
+		return tp
+
+	case *types2.Union:
+		nt := typ.Len()
+		tlist := make([]*types.Type, nt)
+		tildes := make([]bool, nt)
+		for i := range tlist {
+			t := typ.Term(i)
+			tlist[i] = g.typ1(t.Type())
+			tildes[i] = t.Tilde()
+		}
+		return types.NewUnion(tlist, tildes)
+
+	case *types2.Tuple:
+		// Tuples are used for the type of a function call (i.e. the
+		// return value of the function).
+		if typ == nil {
+			return (*types.Type)(nil)
+		}
+		fields := make([]*types.Field, typ.Len())
+		for i := range fields {
+			fields[i] = g.param(typ.At(i))
+		}
+		t := types.NewStruct(types.LocalPkg, fields)
+		t.StructType().Funarg = types.FunargResults
+		return t
+
+	default:
+		base.FatalfAt(src.NoXPos, "unhandled type: %v (%T)", typ, typ)
+		panic("unreachable")
+	}
+}
+
+// fillinMethods fills in the method name nodes and types for a defined type with at
+// least one method. This is needed for later typechecking when looking up methods of
+// instantiated types, and for actually generating the methods for instantiated
+// types.
+func (g *irgen) fillinMethods(typ *types2.Named, ntyp *types.Type) {
+	targs2 := typ.TypeArgs()
+	targs := make([]*types.Type, targs2.Len())
+	for i := range targs {
+		targs[i] = g.typ1(targs2.At(i))
+	}
+
+	methods := make([]*types.Field, typ.NumMethods())
+	for i := range methods {
+		m := typ.Method(i)
+		recvType := deref2(types2.AsSignature(m.Type()).Recv().Type())
+		var meth *ir.Name
+		imported := false
+		if m.Pkg() != g.self {
+			// Imported methods cannot be loaded by name (what
+			// g.obj() does) - they must be loaded via their
+			// type.
+			meth = g.obj(recvType.(*types2.Named).Obj()).Type().Methods().Index(i).Nname.(*ir.Name)
+			// XXX Because Obj() returns the object of the base generic
+			// type, we have to still do the method translation below.
+			imported = true
+		} else {
+			meth = g.obj(m)
+		}
+		assert(recvType == types2.Type(typ))
+		if imported {
+			// Unfortunately, meth is the type of the method of the
+			// generic type, so we have to do a substitution to get
+			// the name/type of the method of the instantiated type,
+			// using m.Type().RParams() and typ.TArgs()
+			inst2 := g.instTypeName2("", typ.TypeArgs())
+			name := meth.Sym().Name
+			i1 := strings.Index(name, "[")
+			i2 := strings.Index(name[i1:], "]")
+			assert(i1 >= 0 && i2 >= 0)
+			// Generate the name of the instantiated method.
+			name = name[0:i1] + inst2 + name[i1+i2+1:]
+			newsym := meth.Sym().Pkg.Lookup(name)
+			var meth2 *ir.Name
+			if newsym.Def != nil {
+				meth2 = newsym.Def.(*ir.Name)
+			} else {
+				meth2 = ir.NewNameAt(meth.Pos(), newsym)
+				rparams := types2.AsSignature(m.Type()).RecvTypeParams()
+				tparams := make([]*types.Type, rparams.Len())
+				// Set g.curDecl to be the method context, so type
+				// params in the receiver of the method that we are
+				// translating gets the right unique name. We could
+				// be in a top-level typeDecl, so save and restore
+				// the current contents of g.curDecl.
+				savedCurDecl := g.curDecl
+				g.curDecl = typ.Obj().Name() + "." + m.Name()
+				for i := range tparams {
+					tparams[i] = g.typ1(rparams.At(i))
+				}
+				g.curDecl = savedCurDecl
+				assert(len(tparams) == len(targs))
+				ts := typecheck.Tsubster{
+					Tparams: tparams,
+					Targs:   targs,
+				}
+				// Do the substitution of the type
+				meth2.SetType(ts.Typ(meth.Type()))
+				newsym.Def = meth2
+			}
+			meth = meth2
+		}
+		methods[i] = types.NewField(meth.Pos(), g.selector(m), meth.Type())
+		methods[i].Nname = meth
+	}
+	ntyp.Methods().Set(methods)
+	if !ntyp.HasTParam() && !ntyp.HasShape() {
+		// Generate all the methods for a new fully-instantiated type.
+		typecheck.NeedInstType(ntyp)
+	}
+}
+
+func (g *irgen) signature(recv *types.Field, sig *types2.Signature) *types.Type {
+	tparams2 := sig.TypeParams()
+	tparams := make([]*types.Field, tparams2.Len())
+	for i := range tparams {
+		tp := tparams2.At(i).Obj()
+		tparams[i] = types.NewField(g.pos(tp), g.sym(tp), g.typ1(tp.Type()))
+	}
+
+	do := func(typ *types2.Tuple) []*types.Field {
+		fields := make([]*types.Field, typ.Len())
+		for i := range fields {
+			fields[i] = g.param(typ.At(i))
+		}
+		return fields
+	}
+	params := do(sig.Params())
+	results := do(sig.Results())
+	if sig.Variadic() {
+		params[len(params)-1].SetIsDDD(true)
+	}
+
+	return types.NewSignature(g.tpkg(sig), recv, tparams, params, results)
+}
+
+func (g *irgen) param(v *types2.Var) *types.Field {
+	return types.NewField(g.pos(v), g.sym(v), g.typ1(v.Type()))
+}
+
+func (g *irgen) sym(obj types2.Object) *types.Sym {
+	if name := obj.Name(); name != "" {
+		return g.pkg(obj.Pkg()).Lookup(obj.Name())
+	}
+	return nil
+}
+
+func (g *irgen) selector(obj types2.Object) *types.Sym {
+	pkg, name := g.pkg(obj.Pkg()), obj.Name()
+	if types.IsExported(name) {
+		pkg = types.LocalPkg
+	}
+	return pkg.Lookup(name)
+}
+
+// tpkg returns the package that a function, interface, struct, or typeparam type
+// expression appeared in.
+//
+// Caveat: For the degenerate types "func()", "interface{}", and
+// "struct{}", tpkg always returns LocalPkg. However, we only need the
+// package information so that go/types can report it via its API, and
+// the reason we fail to return the original package for these
+// particular types is because go/types does *not* report it for
+// them. So in practice this limitation is probably moot.
+func (g *irgen) tpkg(typ types2.Type) *types.Pkg {
+	if obj := anyObj(typ); obj != nil {
+		return g.pkg(obj.Pkg())
+	}
+	return types.LocalPkg
+}
+
+// anyObj returns some object accessible from typ, if any.
+func anyObj(typ types2.Type) types2.Object {
+	switch typ := typ.(type) {
+	case *types2.Signature:
+		if recv := typ.Recv(); recv != nil {
+			return recv
+		}
+		if params := typ.Params(); params.Len() > 0 {
+			return params.At(0)
+		}
+		if results := typ.Results(); results.Len() > 0 {
+			return results.At(0)
+		}
+	case *types2.Struct:
+		if typ.NumFields() > 0 {
+			return typ.Field(0)
+		}
+	case *types2.Interface:
+		if typ.NumExplicitMethods() > 0 {
+			return typ.ExplicitMethod(0)
+		}
+	case *types2.TypeParam:
+		return typ.Obj()
+	}
+	return nil
+}
+
+func (g *irgen) basic(typ *types2.Basic) *types.Type {
+	switch typ.Name() {
+	case "byte":
+		return types.ByteType
+	case "rune":
+		return types.RuneType
+	}
+	return *basics[typ.Kind()]
+}
+
+var basics = [...]**types.Type{
+	types2.Invalid:        new(*types.Type),
+	types2.Bool:           &types.Types[types.TBOOL],
+	types2.Int:            &types.Types[types.TINT],
+	types2.Int8:           &types.Types[types.TINT8],
+	types2.Int16:          &types.Types[types.TINT16],
+	types2.Int32:          &types.Types[types.TINT32],
+	types2.Int64:          &types.Types[types.TINT64],
+	types2.Uint:           &types.Types[types.TUINT],
+	types2.Uint8:          &types.Types[types.TUINT8],
+	types2.Uint16:         &types.Types[types.TUINT16],
+	types2.Uint32:         &types.Types[types.TUINT32],
+	types2.Uint64:         &types.Types[types.TUINT64],
+	types2.Uintptr:        &types.Types[types.TUINTPTR],
+	types2.Float32:        &types.Types[types.TFLOAT32],
+	types2.Float64:        &types.Types[types.TFLOAT64],
+	types2.Complex64:      &types.Types[types.TCOMPLEX64],
+	types2.Complex128:     &types.Types[types.TCOMPLEX128],
+	types2.String:         &types.Types[types.TSTRING],
+	types2.UnsafePointer:  &types.Types[types.TUNSAFEPTR],
+	types2.UntypedBool:    &types.UntypedBool,
+	types2.UntypedInt:     &types.UntypedInt,
+	types2.UntypedRune:    &types.UntypedRune,
+	types2.UntypedFloat:   &types.UntypedFloat,
+	types2.UntypedComplex: &types.UntypedComplex,
+	types2.UntypedString:  &types.UntypedString,
+	types2.UntypedNil:     &types.Types[types.TNIL],
+}
+
+var dirs = [...]types.ChanDir{
+	types2.SendRecv: types.Cboth,
+	types2.SendOnly: types.Csend,
+	types2.RecvOnly: types.Crecv,
+}
+
+// deref2 does a single deref of types2 type t, if it is a pointer type.
+func deref2(t types2.Type) types2.Type {
+	if ptr := types2.AsPointer(t); ptr != nil {
+		t = ptr.Elem()
+	}
+	return t
+}
diff --git a/src/cmd/compile/internal/noder/unified.go b/src/cmd/compile/internal/noder/unified.go
new file mode 100644
index 0000000..25136e6
--- /dev/null
+++ b/src/cmd/compile/internal/noder/unified.go
@@ -0,0 +1,441 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+	"internal/goversion"
+	"internal/pkgbits"
+	"io"
+	"runtime"
+	"sort"
+	"strings"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/inline"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+	"cmd/internal/src"
+)
+
+// localPkgReader holds the package reader used for reading the local
+// package. It exists so the unified IR linker can refer back to it
+// later.
+var localPkgReader *pkgReader
+
+// unified constructs the local package's Internal Representation (IR)
+// from its syntax tree (AST).
+//
+// The pipeline contains 2 steps:
+//
+//  1. Generate the export data "stub".
+//
+//  2. Generate the IR from the export data above.
+//
+// The package data "stub" at step (1) contains everything from the local package,
+// but nothing that has been imported. When we're actually writing out export data
+// to the output files (see writeNewExport), we run the "linker", which:
+//
+//   - Updates compiler extensions data (e.g. inlining cost, escape analysis results).
+//
+//   - Handles re-exporting any transitive dependencies.
+//
+//   - Prunes out any unnecessary details (e.g. non-inlineable functions, because any
+//     downstream importers only care about inlinable functions).
+//
+// The source files are typechecked twice: once before writing the export data
+// using types2, and again after reading the export data using gc/typecheck.
+// The duplication of work will go away once we only use the types2 type checker,
+// removing the gc/typecheck step. For now, it is kept because:
+//
+//   - It reduces the engineering costs in maintaining a fork of typecheck
+//     (e.g. no need to backport fixes like CL 327651).
+//
+//   - It makes it easier to pass toolstash -cmp.
+//
+//   - Historically, we would always re-run the typechecker after importing a package,
+//     even though we know the imported data is valid. It's not ideal, but it's
+//     not causing any problems either.
+//
+//   - gc/typecheck is still in charge of some transformations, such as rewriting
+//     multi-valued function calls or transforming ir.OINDEX to ir.OINDEXMAP.
+//
+// Using the syntax tree with types2, which has a complete representation of generics,
+// the unified IR has the full typed AST needed for introspection during step (1).
+// In other words, we have all the necessary information to build the generic IR form
+// (see writer.captureVars for an example).
+func unified(noders []*noder) {
+	inline.InlineCall = unifiedInlineCall
+	typecheck.HaveInlineBody = unifiedHaveInlineBody
+
+	data := writePkgStub(noders)
+
+	// We already passed base.Flag.Lang to types2 to handle validating
+	// the user's source code. Bump it up now to the current version and
+	// re-parse, so typecheck doesn't complain if we construct IR that
+	// utilizes newer Go features.
+	base.Flag.Lang = fmt.Sprintf("go1.%d", goversion.Version)
+	types.ParseLangFlag()
+
+	target := typecheck.Target
+
+	typecheck.TypecheckAllowed = true
+
+	localPkgReader = newPkgReader(pkgbits.NewPkgDecoder(types.LocalPkg.Path, data))
+	readPackage(localPkgReader, types.LocalPkg, true)
+
+	r := localPkgReader.newReader(pkgbits.RelocMeta, pkgbits.PrivateRootIdx, pkgbits.SyncPrivate)
+	r.pkgInit(types.LocalPkg, target)
+
+	// Type-check any top-level assignments. We ignore non-assignments
+	// here because other declarations are typechecked as they're
+	// constructed.
+	for i, ndecls := 0, len(target.Decls); i < ndecls; i++ {
+		switch n := target.Decls[i]; n.Op() {
+		case ir.OAS, ir.OAS2:
+			target.Decls[i] = typecheck.Stmt(n)
+		}
+	}
+
+	readBodies(target, false)
+
+	// Check that nothing snuck past typechecking.
+	for _, n := range target.Decls {
+		if n.Typecheck() == 0 {
+			base.FatalfAt(n.Pos(), "missed typecheck: %v", n)
+		}
+
+		// For functions, check that at least their first statement (if
+		// any) was typechecked too.
+		if fn, ok := n.(*ir.Func); ok && len(fn.Body) != 0 {
+			if stmt := fn.Body[0]; stmt.Typecheck() == 0 {
+				base.FatalfAt(stmt.Pos(), "missed typecheck: %v", stmt)
+			}
+		}
+	}
+
+	base.ExitIfErrors() // just in case
+}
+
+// readBodies iteratively expands all pending dictionaries and
+// function bodies.
+//
+// If duringInlining is true, then the inline.InlineDecls is called as
+// necessary on instantiations of imported generic functions, so their
+// inlining costs can be computed.
+func readBodies(target *ir.Package, duringInlining bool) {
+	var inlDecls []ir.Node
+
+	// Don't use range--bodyIdx can add closures to todoBodies.
+	for {
+		// The order we expand dictionaries and bodies doesn't matter, so
+		// pop from the end to reduce todoBodies reallocations if it grows
+		// further.
+		//
+		// However, we do at least need to flush any pending dictionaries
+		// before reading bodies, because bodies might reference the
+		// dictionaries.
+
+		if len(todoDicts) > 0 {
+			fn := todoDicts[len(todoDicts)-1]
+			todoDicts = todoDicts[:len(todoDicts)-1]
+			fn()
+			continue
+		}
+
+		if len(todoBodies) > 0 {
+			fn := todoBodies[len(todoBodies)-1]
+			todoBodies = todoBodies[:len(todoBodies)-1]
+
+			pri, ok := bodyReader[fn]
+			assert(ok)
+			pri.funcBody(fn)
+
+			// Instantiated generic function: add to Decls for typechecking
+			// and compilation.
+			if fn.OClosure == nil && len(pri.dict.targs) != 0 {
+				// cmd/link does not support a type symbol referencing a method symbol
+				// across DSO boundary, so force re-compiling methods on a generic type
+				// even it was seen from imported package in linkshared mode, see #58966.
+				canSkipNonGenericMethod := !(base.Ctxt.Flag_linkshared && ir.IsMethod(fn))
+				if duringInlining && canSkipNonGenericMethod {
+					inlDecls = append(inlDecls, fn)
+				} else {
+					target.Decls = append(target.Decls, fn)
+				}
+			}
+
+			continue
+		}
+
+		break
+	}
+
+	todoDicts = nil
+	todoBodies = nil
+
+	if len(inlDecls) != 0 {
+		// If we instantiated any generic functions during inlining, we need
+		// to call CanInline on them so they'll be transitively inlined
+		// correctly (#56280).
+		//
+		// We know these functions were already compiled in an imported
+		// package though, so we don't need to actually apply InlineCalls or
+		// save the function bodies any further than this.
+		//
+		// We can also lower the -m flag to 0, to suppress duplicate "can
+		// inline" diagnostics reported against the imported package. Again,
+		// we already reported those diagnostics in the original package, so
+		// it's pointless repeating them here.
+
+		oldLowerM := base.Flag.LowerM
+		base.Flag.LowerM = 0
+		inline.InlineDecls(nil, inlDecls, false)
+		base.Flag.LowerM = oldLowerM
+
+		for _, fn := range inlDecls {
+			fn.(*ir.Func).Body = nil // free memory
+		}
+	}
+}
+
+// writePkgStub type checks the given parsed source files,
+// writes an export data package stub representing them,
+// and returns the result.
+func writePkgStub(noders []*noder) string {
+	m, pkg, info := checkFiles(noders)
+
+	pw := newPkgWriter(m, pkg, info)
+
+	pw.collectDecls(noders)
+
+	publicRootWriter := pw.newWriter(pkgbits.RelocMeta, pkgbits.SyncPublic)
+	privateRootWriter := pw.newWriter(pkgbits.RelocMeta, pkgbits.SyncPrivate)
+
+	assert(publicRootWriter.Idx == pkgbits.PublicRootIdx)
+	assert(privateRootWriter.Idx == pkgbits.PrivateRootIdx)
+
+	{
+		w := publicRootWriter
+		w.pkg(pkg)
+		w.Bool(false) // TODO(mdempsky): Remove; was "has init"
+
+		scope := pkg.Scope()
+		names := scope.Names()
+		w.Len(len(names))
+		for _, name := range names {
+			w.obj(scope.Lookup(name), nil)
+		}
+
+		w.Sync(pkgbits.SyncEOF)
+		w.Flush()
+	}
+
+	{
+		w := privateRootWriter
+		w.pkgInit(noders)
+		w.Flush()
+	}
+
+	var sb strings.Builder
+	pw.DumpTo(&sb)
+
+	// At this point, we're done with types2. Make sure the package is
+	// garbage collected.
+	freePackage(pkg)
+
+	return sb.String()
+}
+
+// freePackage ensures the given package is garbage collected.
+func freePackage(pkg *types2.Package) {
+	// The GC test below relies on a precise GC that runs finalizers as
+	// soon as objects are unreachable. Our implementation provides
+	// this, but other/older implementations may not (e.g., Go 1.4 does
+	// not because of #22350). To avoid imposing unnecessary
+	// restrictions on the GOROOT_BOOTSTRAP toolchain, we skip the test
+	// during bootstrapping.
+	if base.CompilerBootstrap || base.Debug.GCCheck == 0 {
+		*pkg = types2.Package{}
+		return
+	}
+
+	// Set a finalizer on pkg so we can detect if/when it's collected.
+	done := make(chan struct{})
+	runtime.SetFinalizer(pkg, func(*types2.Package) { close(done) })
+
+	// Important: objects involved in cycles are not finalized, so zero
+	// out pkg to break its cycles and allow the finalizer to run.
+	*pkg = types2.Package{}
+
+	// It typically takes just 1 or 2 cycles to release pkg, but it
+	// doesn't hurt to try a few more times.
+	for i := 0; i < 10; i++ {
+		select {
+		case <-done:
+			return
+		default:
+			runtime.GC()
+		}
+	}
+
+	base.Fatalf("package never finalized")
+}
+
+// readPackage reads package export data from pr to populate
+// importpkg.
+//
+// localStub indicates whether pr is reading the stub export data for
+// the local package, as opposed to relocated export data for an
+// import.
+func readPackage(pr *pkgReader, importpkg *types.Pkg, localStub bool) {
+	{
+		r := pr.newReader(pkgbits.RelocMeta, pkgbits.PublicRootIdx, pkgbits.SyncPublic)
+
+		pkg := r.pkg()
+		base.Assertf(pkg == importpkg, "have package %q (%p), want package %q (%p)", pkg.Path, pkg, importpkg.Path, importpkg)
+
+		r.Bool() // TODO(mdempsky): Remove; was "has init"
+
+		for i, n := 0, r.Len(); i < n; i++ {
+			r.Sync(pkgbits.SyncObject)
+			assert(!r.Bool())
+			idx := r.Reloc(pkgbits.RelocObj)
+			assert(r.Len() == 0)
+
+			path, name, code := r.p.PeekObj(idx)
+			if code != pkgbits.ObjStub {
+				objReader[types.NewPkg(path, "").Lookup(name)] = pkgReaderIndex{pr, idx, nil, nil, nil}
+			}
+		}
+
+		r.Sync(pkgbits.SyncEOF)
+	}
+
+	if !localStub {
+		r := pr.newReader(pkgbits.RelocMeta, pkgbits.PrivateRootIdx, pkgbits.SyncPrivate)
+
+		if r.Bool() {
+			sym := importpkg.Lookup(".inittask")
+			task := ir.NewNameAt(src.NoXPos, sym)
+			task.Class = ir.PEXTERN
+			sym.Def = task
+		}
+
+		for i, n := 0, r.Len(); i < n; i++ {
+			path := r.String()
+			name := r.String()
+			idx := r.Reloc(pkgbits.RelocBody)
+
+			sym := types.NewPkg(path, "").Lookup(name)
+			if _, ok := importBodyReader[sym]; !ok {
+				importBodyReader[sym] = pkgReaderIndex{pr, idx, nil, nil, nil}
+			}
+		}
+
+		r.Sync(pkgbits.SyncEOF)
+	}
+}
+
+// writeUnifiedExport writes to `out` the finalized, self-contained
+// Unified IR export data file for the current compilation unit.
+func writeUnifiedExport(out io.Writer) {
+	l := linker{
+		pw: pkgbits.NewPkgEncoder(base.Debug.SyncFrames),
+
+		pkgs:   make(map[string]pkgbits.Index),
+		decls:  make(map[*types.Sym]pkgbits.Index),
+		bodies: make(map[*types.Sym]pkgbits.Index),
+	}
+
+	publicRootWriter := l.pw.NewEncoder(pkgbits.RelocMeta, pkgbits.SyncPublic)
+	privateRootWriter := l.pw.NewEncoder(pkgbits.RelocMeta, pkgbits.SyncPrivate)
+	assert(publicRootWriter.Idx == pkgbits.PublicRootIdx)
+	assert(privateRootWriter.Idx == pkgbits.PrivateRootIdx)
+
+	var selfPkgIdx pkgbits.Index
+
+	{
+		pr := localPkgReader
+		r := pr.NewDecoder(pkgbits.RelocMeta, pkgbits.PublicRootIdx, pkgbits.SyncPublic)
+
+		r.Sync(pkgbits.SyncPkg)
+		selfPkgIdx = l.relocIdx(pr, pkgbits.RelocPkg, r.Reloc(pkgbits.RelocPkg))
+
+		r.Bool() // TODO(mdempsky): Remove; was "has init"
+
+		for i, n := 0, r.Len(); i < n; i++ {
+			r.Sync(pkgbits.SyncObject)
+			assert(!r.Bool())
+			idx := r.Reloc(pkgbits.RelocObj)
+			assert(r.Len() == 0)
+
+			xpath, xname, xtag := pr.PeekObj(idx)
+			assert(xpath == pr.PkgPath())
+			assert(xtag != pkgbits.ObjStub)
+
+			if types.IsExported(xname) {
+				l.relocIdx(pr, pkgbits.RelocObj, idx)
+			}
+		}
+
+		r.Sync(pkgbits.SyncEOF)
+	}
+
+	{
+		var idxs []pkgbits.Index
+		for _, idx := range l.decls {
+			idxs = append(idxs, idx)
+		}
+		sort.Slice(idxs, func(i, j int) bool { return idxs[i] < idxs[j] })
+
+		w := publicRootWriter
+
+		w.Sync(pkgbits.SyncPkg)
+		w.Reloc(pkgbits.RelocPkg, selfPkgIdx)
+		w.Bool(false) // TODO(mdempsky): Remove; was "has init"
+
+		w.Len(len(idxs))
+		for _, idx := range idxs {
+			w.Sync(pkgbits.SyncObject)
+			w.Bool(false)
+			w.Reloc(pkgbits.RelocObj, idx)
+			w.Len(0)
+		}
+
+		w.Sync(pkgbits.SyncEOF)
+		w.Flush()
+	}
+
+	{
+		type symIdx struct {
+			sym *types.Sym
+			idx pkgbits.Index
+		}
+		var bodies []symIdx
+		for sym, idx := range l.bodies {
+			bodies = append(bodies, symIdx{sym, idx})
+		}
+		sort.Slice(bodies, func(i, j int) bool { return bodies[i].idx < bodies[j].idx })
+
+		w := privateRootWriter
+
+		w.Bool(typecheck.Lookup(".inittask").Def != nil)
+
+		w.Len(len(bodies))
+		for _, body := range bodies {
+			w.String(body.sym.Pkg.Path)
+			w.String(body.sym.Name)
+			w.Reloc(pkgbits.RelocBody, body.idx)
+		}
+
+		w.Sync(pkgbits.SyncEOF)
+		w.Flush()
+	}
+
+	base.Ctxt.Fingerprint = l.pw.DumpTo(out)
+}
diff --git a/src/cmd/compile/internal/noder/validate.go b/src/cmd/compile/internal/noder/validate.go
new file mode 100644
index 0000000..baf8bd3
--- /dev/null
+++ b/src/cmd/compile/internal/noder/validate.go
@@ -0,0 +1,132 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"go/constant"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+)
+
+// match reports whether types t1 and t2 are consistent
+// representations for a given expression's type.
+func (g *irgen) match(t1 *types.Type, t2 types2.Type, hasOK bool) bool {
+	tuple, ok := t2.(*types2.Tuple)
+	if !ok {
+		// Not a tuple; can use simple type identity comparison.
+		return types.Identical(t1, g.typ(t2))
+	}
+
+	if hasOK {
+		// For has-ok values, types2 represents the expression's type as a
+		// 2-element tuple, whereas ir just uses the first type and infers
+		// that the second type is boolean. Must match either, since we
+		// sometimes delay the transformation to the ir form.
+		if tuple.Len() == 2 && types.Identical(t1, g.typ(tuple.At(0).Type())) {
+			return true
+		}
+		return types.Identical(t1, g.typ(t2))
+	}
+
+	if t1 == nil || tuple == nil {
+		return t1 == nil && tuple == nil
+	}
+	if !t1.IsFuncArgStruct() {
+		return false
+	}
+	if t1.NumFields() != tuple.Len() {
+		return false
+	}
+	for i, result := range t1.FieldSlice() {
+		if !types.Identical(result.Type, g.typ(tuple.At(i).Type())) {
+			return false
+		}
+	}
+	return true
+}
+
+func (g *irgen) validate(n syntax.Node) {
+	switch n := n.(type) {
+	case *syntax.CallExpr:
+		tv := g.typeAndValue(n.Fun)
+		if tv.IsBuiltin() {
+			fun := n.Fun
+			for {
+				builtin, ok := fun.(*syntax.ParenExpr)
+				if !ok {
+					break
+				}
+				fun = builtin.X
+			}
+			switch builtin := fun.(type) {
+			case *syntax.Name:
+				g.validateBuiltin(builtin.Value, n)
+			case *syntax.SelectorExpr:
+				g.validateBuiltin(builtin.Sel.Value, n)
+			default:
+				g.unhandled("builtin", n)
+			}
+		}
+	}
+}
+
+func (g *irgen) validateBuiltin(name string, call *syntax.CallExpr) {
+	switch name {
+	case "Alignof", "Offsetof", "Sizeof":
+		// Check that types2+gcSizes calculates sizes the same
+		// as cmd/compile does.
+
+		tv := g.typeAndValue(call)
+		if !tv.IsValue() {
+			base.FatalfAt(g.pos(call), "expected a value")
+		}
+
+		if tv.Value == nil {
+			break // unsafe op is not a constant, so no further validation
+		}
+
+		got, ok := constant.Int64Val(tv.Value)
+		if !ok {
+			base.FatalfAt(g.pos(call), "expected int64 constant value")
+		}
+
+		want := g.unsafeExpr(name, call.ArgList[0])
+		if got != want {
+			base.FatalfAt(g.pos(call), "got %v from types2, but want %v", got, want)
+		}
+	}
+}
+
+// unsafeExpr evaluates the given unsafe builtin function on arg.
+func (g *irgen) unsafeExpr(name string, arg syntax.Expr) int64 {
+	switch name {
+	case "Alignof":
+		return g.typ(g.type2(arg)).Alignment()
+	case "Sizeof":
+		return g.typ(g.type2(arg)).Size()
+	}
+
+	// Offsetof
+
+	sel := arg.(*syntax.SelectorExpr)
+	selection := g.info.Selections[sel]
+
+	typ := g.typ(g.type2(sel.X))
+	typ = deref(typ)
+
+	var offset int64
+	for _, i := range selection.Index() {
+		// Ensure field offsets have been calculated.
+		types.CalcSize(typ)
+
+		f := typ.Field(i)
+		offset += f.Offset
+		typ = f.Type
+	}
+	return offset
+}
diff --git a/src/cmd/compile/internal/noder/writer.go b/src/cmd/compile/internal/noder/writer.go
new file mode 100644
index 0000000..da5c1e9
--- /dev/null
+++ b/src/cmd/compile/internal/noder/writer.go
@@ -0,0 +1,2735 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package noder
+
+import (
+	"fmt"
+	"internal/pkgbits"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/syntax"
+	"cmd/compile/internal/types"
+	"cmd/compile/internal/types2"
+)
+
+// This file implements the Unified IR package writer and defines the
+// Unified IR export data format.
+//
+// Low-level coding details (e.g., byte-encoding of individual
+// primitive values, or handling element bitstreams and
+// cross-references) are handled by internal/pkgbits, so here we only
+// concern ourselves with higher-level worries like mapping Go
+// language constructs into elements.
+
+// There are two central types in the writing process: the "writer"
+// type handles writing out individual elements, while the "pkgWriter"
+// type keeps track of which elements have already been created.
+//
+// For each sort of "thing" (e.g., position, package, object, type)
+// that can be written into the export data, there are generally
+// several methods that work together:
+//
+// - writer.thing handles writing out a *use* of a thing, which often
+//   means writing a relocation to that thing's encoded index.
+//
+// - pkgWriter.thingIdx handles reserving an index for a thing, and
+//   writing out any elements needed for the thing.
+//
+// - writer.doThing handles writing out the *definition* of a thing,
+//   which in general is a mix of low-level coding primitives (e.g.,
+//   ints and strings) or uses of other things.
+//
+// A design goal of Unified IR is to have a single, canonical writer
+// implementation, but multiple reader implementations each tailored
+// to their respective needs. For example, within cmd/compile's own
+// backend, inlining is implemented largely by just re-running the
+// function body reading code.
+
+// TODO(mdempsky): Add an importer for Unified IR to the x/tools repo,
+// and better document the file format boundary between public and
+// private data.
+
+// A pkgWriter constructs Unified IR export data from the results of
+// running the types2 type checker on a Go compilation unit.
+type pkgWriter struct {
+	pkgbits.PkgEncoder
+
+	m      posMap
+	curpkg *types2.Package
+	info   *types2.Info
+
+	// Indices for previously written syntax and types2 things.
+
+	posBasesIdx map[*syntax.PosBase]pkgbits.Index
+	pkgsIdx     map[*types2.Package]pkgbits.Index
+	typsIdx     map[types2.Type]pkgbits.Index
+	objsIdx     map[types2.Object]pkgbits.Index
+
+	// Maps from types2.Objects back to their syntax.Decl.
+
+	funDecls map[*types2.Func]*syntax.FuncDecl
+	typDecls map[*types2.TypeName]typeDeclGen
+
+	// linknames maps package-scope objects to their linker symbol name,
+	// if specified by a //go:linkname directive.
+	linknames map[types2.Object]string
+
+	// cgoPragmas accumulates any //go:cgo_* pragmas that need to be
+	// passed through to cmd/link.
+	cgoPragmas [][]string
+}
+
+// newPkgWriter returns an initialized pkgWriter for the specified
+// package.
+func newPkgWriter(m posMap, pkg *types2.Package, info *types2.Info) *pkgWriter {
+	return &pkgWriter{
+		PkgEncoder: pkgbits.NewPkgEncoder(base.Debug.SyncFrames),
+
+		m:      m,
+		curpkg: pkg,
+		info:   info,
+
+		pkgsIdx: make(map[*types2.Package]pkgbits.Index),
+		objsIdx: make(map[types2.Object]pkgbits.Index),
+		typsIdx: make(map[types2.Type]pkgbits.Index),
+
+		posBasesIdx: make(map[*syntax.PosBase]pkgbits.Index),
+
+		funDecls: make(map[*types2.Func]*syntax.FuncDecl),
+		typDecls: make(map[*types2.TypeName]typeDeclGen),
+
+		linknames: make(map[types2.Object]string),
+	}
+}
+
+// errorf reports a user error about thing p.
+func (pw *pkgWriter) errorf(p poser, msg string, args ...interface{}) {
+	base.ErrorfAt(pw.m.pos(p), msg, args...)
+}
+
+// fatalf reports an internal compiler error about thing p.
+func (pw *pkgWriter) fatalf(p poser, msg string, args ...interface{}) {
+	base.FatalfAt(pw.m.pos(p), msg, args...)
+}
+
+// unexpected reports a fatal error about a thing of unexpected
+// dynamic type.
+func (pw *pkgWriter) unexpected(what string, p poser) {
+	pw.fatalf(p, "unexpected %s: %v (%T)", what, p, p)
+}
+
+func (pw *pkgWriter) typeAndValue(x syntax.Expr) syntax.TypeAndValue {
+	tv := x.GetTypeInfo()
+	if tv.Type == nil {
+		pw.fatalf(x, "missing Types entry: %v", syntax.String(x))
+	}
+	return tv
+}
+func (pw *pkgWriter) maybeTypeAndValue(x syntax.Expr) (syntax.TypeAndValue, bool) {
+	tv := x.GetTypeInfo()
+	return tv, tv.Type != nil
+}
+
+// typeOf returns the Type of the given value expression.
+func (pw *pkgWriter) typeOf(expr syntax.Expr) types2.Type {
+	tv := pw.typeAndValue(expr)
+	if !tv.IsValue() {
+		pw.fatalf(expr, "expected value: %v", syntax.String(expr))
+	}
+	return tv.Type
+}
+
+// A writer provides APIs for writing out an individual element.
+type writer struct {
+	p *pkgWriter
+
+	pkgbits.Encoder
+
+	// sig holds the signature for the current function body, if any.
+	sig *types2.Signature
+
+	// TODO(mdempsky): We should be able to prune localsIdx whenever a
+	// scope closes, and then maybe we can just use the same map for
+	// storing the TypeParams too (as their TypeName instead).
+
+	// localsIdx tracks any local variables declared within this
+	// function body. It's unused for writing out non-body things.
+	localsIdx map[*types2.Var]int
+
+	// closureVars tracks any free variables that are referenced by this
+	// function body. It's unused for writing out non-body things.
+	closureVars    []posVar
+	closureVarsIdx map[*types2.Var]int // index of previously seen free variables
+
+	dict *writerDict
+
+	// derived tracks whether the type being written out references any
+	// type parameters. It's unused for writing non-type things.
+	derived bool
+}
+
+// A writerDict tracks types and objects that are used by a declaration.
+type writerDict struct {
+	implicits []*types2.TypeName
+
+	// derived is a slice of type indices for computing derived types
+	// (i.e., types that depend on the declaration's type parameters).
+	derived []derivedInfo
+
+	// derivedIdx maps a Type to its corresponding index within the
+	// derived slice, if present.
+	derivedIdx map[types2.Type]pkgbits.Index
+
+	// These slices correspond to entries in the runtime dictionary.
+	typeParamMethodExprs []writerMethodExprInfo
+	subdicts             []objInfo
+	rtypes               []typeInfo
+	itabs                []itabInfo
+}
+
+type itabInfo struct {
+	typ   typeInfo
+	iface typeInfo
+}
+
+// typeParamIndex returns the index of the given type parameter within
+// the dictionary. This may differ from typ.Index() when there are
+// implicit type parameters due to defined types declared within a
+// generic function or method.
+func (dict *writerDict) typeParamIndex(typ *types2.TypeParam) int {
+	for idx, implicit := range dict.implicits {
+		if implicit.Type().(*types2.TypeParam) == typ {
+			return idx
+		}
+	}
+
+	return len(dict.implicits) + typ.Index()
+}
+
+// A derivedInfo represents a reference to an encoded generic Go type.
+type derivedInfo struct {
+	idx    pkgbits.Index
+	needed bool // TODO(mdempsky): Remove.
+}
+
+// A typeInfo represents a reference to an encoded Go type.
+//
+// If derived is true, then the typeInfo represents a generic Go type
+// that contains type parameters. In this case, idx is an index into
+// the readerDict.derived{,Types} arrays.
+//
+// Otherwise, the typeInfo represents a non-generic Go type, and idx
+// is an index into the reader.typs array instead.
+type typeInfo struct {
+	idx     pkgbits.Index
+	derived bool
+}
+
+// An objInfo represents a reference to an encoded, instantiated (if
+// applicable) Go object.
+type objInfo struct {
+	idx       pkgbits.Index // index for the generic function declaration
+	explicits []typeInfo    // info for the type arguments
+}
+
+// A selectorInfo represents a reference to an encoded field or method
+// name (i.e., objects that can only be accessed using selector
+// expressions).
+type selectorInfo struct {
+	pkgIdx  pkgbits.Index
+	nameIdx pkgbits.Index
+}
+
+// anyDerived reports whether any of info's explicit type arguments
+// are derived types.
+func (info objInfo) anyDerived() bool {
+	for _, explicit := range info.explicits {
+		if explicit.derived {
+			return true
+		}
+	}
+	return false
+}
+
+// equals reports whether info and other represent the same Go object
+// (i.e., same base object and identical type arguments, if any).
+func (info objInfo) equals(other objInfo) bool {
+	if info.idx != other.idx {
+		return false
+	}
+	assert(len(info.explicits) == len(other.explicits))
+	for i, targ := range info.explicits {
+		if targ != other.explicits[i] {
+			return false
+		}
+	}
+	return true
+}
+
+type writerMethodExprInfo struct {
+	typeParamIdx int
+	methodInfo   selectorInfo
+}
+
+// typeParamMethodExprIdx returns the index where the given encoded
+// method expression function pointer appears within this dictionary's
+// type parameters method expressions section, adding it if necessary.
+func (dict *writerDict) typeParamMethodExprIdx(typeParamIdx int, methodInfo selectorInfo) int {
+	newInfo := writerMethodExprInfo{typeParamIdx, methodInfo}
+
+	for idx, oldInfo := range dict.typeParamMethodExprs {
+		if oldInfo == newInfo {
+			return idx
+		}
+	}
+
+	idx := len(dict.typeParamMethodExprs)
+	dict.typeParamMethodExprs = append(dict.typeParamMethodExprs, newInfo)
+	return idx
+}
+
+// subdictIdx returns the index where the given encoded object's
+// runtime dictionary appears within this dictionary's subdictionary
+// section, adding it if necessary.
+func (dict *writerDict) subdictIdx(newInfo objInfo) int {
+	for idx, oldInfo := range dict.subdicts {
+		if oldInfo.equals(newInfo) {
+			return idx
+		}
+	}
+
+	idx := len(dict.subdicts)
+	dict.subdicts = append(dict.subdicts, newInfo)
+	return idx
+}
+
+// rtypeIdx returns the index where the given encoded type's
+// *runtime._type value appears within this dictionary's rtypes
+// section, adding it if necessary.
+func (dict *writerDict) rtypeIdx(newInfo typeInfo) int {
+	for idx, oldInfo := range dict.rtypes {
+		if oldInfo == newInfo {
+			return idx
+		}
+	}
+
+	idx := len(dict.rtypes)
+	dict.rtypes = append(dict.rtypes, newInfo)
+	return idx
+}
+
+// itabIdx returns the index where the given encoded type pair's
+// *runtime.itab value appears within this dictionary's itabs section,
+// adding it if necessary.
+func (dict *writerDict) itabIdx(typInfo, ifaceInfo typeInfo) int {
+	newInfo := itabInfo{typInfo, ifaceInfo}
+
+	for idx, oldInfo := range dict.itabs {
+		if oldInfo == newInfo {
+			return idx
+		}
+	}
+
+	idx := len(dict.itabs)
+	dict.itabs = append(dict.itabs, newInfo)
+	return idx
+}
+
+func (pw *pkgWriter) newWriter(k pkgbits.RelocKind, marker pkgbits.SyncMarker) *writer {
+	return &writer{
+		Encoder: pw.NewEncoder(k, marker),
+		p:       pw,
+	}
+}
+
+// @@@ Positions
+
+// pos writes the position of p into the element bitstream.
+func (w *writer) pos(p poser) {
+	w.Sync(pkgbits.SyncPos)
+	pos := p.Pos()
+
+	// TODO(mdempsky): Track down the remaining cases here and fix them.
+	if !w.Bool(pos.IsKnown()) {
+		return
+	}
+
+	// TODO(mdempsky): Delta encoding.
+	w.posBase(pos.Base())
+	w.Uint(pos.Line())
+	w.Uint(pos.Col())
+}
+
+// posBase writes a reference to the given PosBase into the element
+// bitstream.
+func (w *writer) posBase(b *syntax.PosBase) {
+	w.Reloc(pkgbits.RelocPosBase, w.p.posBaseIdx(b))
+}
+
+// posBaseIdx returns the index for the given PosBase.
+func (pw *pkgWriter) posBaseIdx(b *syntax.PosBase) pkgbits.Index {
+	if idx, ok := pw.posBasesIdx[b]; ok {
+		return idx
+	}
+
+	w := pw.newWriter(pkgbits.RelocPosBase, pkgbits.SyncPosBase)
+	w.p.posBasesIdx[b] = w.Idx
+
+	w.String(trimFilename(b))
+
+	if !w.Bool(b.IsFileBase()) {
+		w.pos(b)
+		w.Uint(b.Line())
+		w.Uint(b.Col())
+	}
+
+	return w.Flush()
+}
+
+// @@@ Packages
+
+// pkg writes a use of the given Package into the element bitstream.
+func (w *writer) pkg(pkg *types2.Package) {
+	w.pkgRef(w.p.pkgIdx(pkg))
+}
+
+func (w *writer) pkgRef(idx pkgbits.Index) {
+	w.Sync(pkgbits.SyncPkg)
+	w.Reloc(pkgbits.RelocPkg, idx)
+}
+
+// pkgIdx returns the index for the given package, adding it to the
+// package export data if needed.
+func (pw *pkgWriter) pkgIdx(pkg *types2.Package) pkgbits.Index {
+	if idx, ok := pw.pkgsIdx[pkg]; ok {
+		return idx
+	}
+
+	w := pw.newWriter(pkgbits.RelocPkg, pkgbits.SyncPkgDef)
+	pw.pkgsIdx[pkg] = w.Idx
+
+	// The universe and package unsafe need to be handled specially by
+	// importers anyway, so we serialize them using just their package
+	// path. This ensures that readers don't confuse them for
+	// user-defined packages.
+	switch pkg {
+	case nil: // universe
+		w.String("builtin") // same package path used by godoc
+	case types2.Unsafe:
+		w.String("unsafe")
+	default:
+		// TODO(mdempsky): Write out pkg.Path() for curpkg too.
+		var path string
+		if pkg != w.p.curpkg {
+			path = pkg.Path()
+		}
+		base.Assertf(path != "builtin" && path != "unsafe", "unexpected path for user-defined package: %q", path)
+		w.String(path)
+		w.String(pkg.Name())
+
+		w.Len(len(pkg.Imports()))
+		for _, imp := range pkg.Imports() {
+			w.pkg(imp)
+		}
+	}
+
+	return w.Flush()
+}
+
+// @@@ Types
+
+var (
+	anyTypeName        = types2.Universe.Lookup("any").(*types2.TypeName)
+	comparableTypeName = types2.Universe.Lookup("comparable").(*types2.TypeName)
+	runeTypeName       = types2.Universe.Lookup("rune").(*types2.TypeName)
+)
+
+// typ writes a use of the given type into the bitstream.
+func (w *writer) typ(typ types2.Type) {
+	w.typInfo(w.p.typIdx(typ, w.dict))
+}
+
+// typInfo writes a use of the given type (specified as a typeInfo
+// instead) into the bitstream.
+func (w *writer) typInfo(info typeInfo) {
+	w.Sync(pkgbits.SyncType)
+	if w.Bool(info.derived) {
+		w.Len(int(info.idx))
+		w.derived = true
+	} else {
+		w.Reloc(pkgbits.RelocType, info.idx)
+	}
+}
+
+// typIdx returns the index where the export data description of type
+// can be read back in. If no such index exists yet, it's created.
+//
+// typIdx also reports whether typ is a derived type; that is, whether
+// its identity depends on type parameters.
+func (pw *pkgWriter) typIdx(typ types2.Type, dict *writerDict) typeInfo {
+	if idx, ok := pw.typsIdx[typ]; ok {
+		return typeInfo{idx: idx, derived: false}
+	}
+	if dict != nil {
+		if idx, ok := dict.derivedIdx[typ]; ok {
+			return typeInfo{idx: idx, derived: true}
+		}
+	}
+
+	w := pw.newWriter(pkgbits.RelocType, pkgbits.SyncTypeIdx)
+	w.dict = dict
+
+	switch typ := typ.(type) {
+	default:
+		base.Fatalf("unexpected type: %v (%T)", typ, typ)
+
+	case *types2.Basic:
+		switch kind := typ.Kind(); {
+		case kind == types2.Invalid:
+			base.Fatalf("unexpected types2.Invalid")
+
+		case types2.Typ[kind] == typ:
+			w.Code(pkgbits.TypeBasic)
+			w.Len(int(kind))
+
+		default:
+			// Handle "byte" and "rune" as references to their TypeNames.
+			obj := types2.Universe.Lookup(typ.Name())
+			assert(obj.Type() == typ)
+
+			w.Code(pkgbits.TypeNamed)
+			w.obj(obj, nil)
+		}
+
+	case *types2.Named:
+		obj, targs := splitNamed(typ)
+
+		// Defined types that are declared within a generic function (and
+		// thus have implicit type parameters) are always derived types.
+		if w.p.hasImplicitTypeParams(obj) {
+			w.derived = true
+		}
+
+		w.Code(pkgbits.TypeNamed)
+		w.obj(obj, targs)
+
+	case *types2.TypeParam:
+		w.derived = true
+		w.Code(pkgbits.TypeTypeParam)
+		w.Len(w.dict.typeParamIndex(typ))
+
+	case *types2.Array:
+		w.Code(pkgbits.TypeArray)
+		w.Uint64(uint64(typ.Len()))
+		w.typ(typ.Elem())
+
+	case *types2.Chan:
+		w.Code(pkgbits.TypeChan)
+		w.Len(int(typ.Dir()))
+		w.typ(typ.Elem())
+
+	case *types2.Map:
+		w.Code(pkgbits.TypeMap)
+		w.typ(typ.Key())
+		w.typ(typ.Elem())
+
+	case *types2.Pointer:
+		w.Code(pkgbits.TypePointer)
+		w.typ(typ.Elem())
+
+	case *types2.Signature:
+		base.Assertf(typ.TypeParams() == nil, "unexpected type params: %v", typ)
+		w.Code(pkgbits.TypeSignature)
+		w.signature(typ)
+
+	case *types2.Slice:
+		w.Code(pkgbits.TypeSlice)
+		w.typ(typ.Elem())
+
+	case *types2.Struct:
+		w.Code(pkgbits.TypeStruct)
+		w.structType(typ)
+
+	case *types2.Interface:
+		// Handle "any" as reference to its TypeName.
+		if typ == anyTypeName.Type() {
+			w.Code(pkgbits.TypeNamed)
+			w.obj(anyTypeName, nil)
+			break
+		}
+
+		w.Code(pkgbits.TypeInterface)
+		w.interfaceType(typ)
+
+	case *types2.Union:
+		w.Code(pkgbits.TypeUnion)
+		w.unionType(typ)
+	}
+
+	if w.derived {
+		idx := pkgbits.Index(len(dict.derived))
+		dict.derived = append(dict.derived, derivedInfo{idx: w.Flush()})
+		dict.derivedIdx[typ] = idx
+		return typeInfo{idx: idx, derived: true}
+	}
+
+	pw.typsIdx[typ] = w.Idx
+	return typeInfo{idx: w.Flush(), derived: false}
+}
+
+func (w *writer) structType(typ *types2.Struct) {
+	w.Len(typ.NumFields())
+	for i := 0; i < typ.NumFields(); i++ {
+		f := typ.Field(i)
+		w.pos(f)
+		w.selector(f)
+		w.typ(f.Type())
+		w.String(typ.Tag(i))
+		w.Bool(f.Embedded())
+	}
+}
+
+func (w *writer) unionType(typ *types2.Union) {
+	w.Len(typ.Len())
+	for i := 0; i < typ.Len(); i++ {
+		t := typ.Term(i)
+		w.Bool(t.Tilde())
+		w.typ(t.Type())
+	}
+}
+
+func (w *writer) interfaceType(typ *types2.Interface) {
+	// If typ has no embedded types but it's not a basic interface, then
+	// the natural description we write out below will fail to
+	// reconstruct it.
+	if typ.NumEmbeddeds() == 0 && !typ.IsMethodSet() {
+		// Currently, this can only happen for the underlying Interface of
+		// "comparable", which is needed to handle type declarations like
+		// "type C comparable".
+		assert(typ == comparableTypeName.Type().(*types2.Named).Underlying())
+
+		// Export as "interface{ comparable }".
+		w.Len(0)                         // NumExplicitMethods
+		w.Len(1)                         // NumEmbeddeds
+		w.Bool(false)                    // IsImplicit
+		w.typ(comparableTypeName.Type()) // EmbeddedType(0)
+		return
+	}
+
+	w.Len(typ.NumExplicitMethods())
+	w.Len(typ.NumEmbeddeds())
+
+	if typ.NumExplicitMethods() == 0 && typ.NumEmbeddeds() == 1 {
+		w.Bool(typ.IsImplicit())
+	} else {
+		// Implicit interfaces always have 0 explicit methods and 1
+		// embedded type, so we skip writing out the implicit flag
+		// otherwise as a space optimization.
+		assert(!typ.IsImplicit())
+	}
+
+	for i := 0; i < typ.NumExplicitMethods(); i++ {
+		m := typ.ExplicitMethod(i)
+		sig := m.Type().(*types2.Signature)
+		assert(sig.TypeParams() == nil)
+
+		w.pos(m)
+		w.selector(m)
+		w.signature(sig)
+	}
+
+	for i := 0; i < typ.NumEmbeddeds(); i++ {
+		w.typ(typ.EmbeddedType(i))
+	}
+}
+
+func (w *writer) signature(sig *types2.Signature) {
+	w.Sync(pkgbits.SyncSignature)
+	w.params(sig.Params())
+	w.params(sig.Results())
+	w.Bool(sig.Variadic())
+}
+
+func (w *writer) params(typ *types2.Tuple) {
+	w.Sync(pkgbits.SyncParams)
+	w.Len(typ.Len())
+	for i := 0; i < typ.Len(); i++ {
+		w.param(typ.At(i))
+	}
+}
+
+func (w *writer) param(param *types2.Var) {
+	w.Sync(pkgbits.SyncParam)
+	w.pos(param)
+	w.localIdent(param)
+	w.typ(param.Type())
+}
+
+// @@@ Objects
+
+// obj writes a use of the given object into the bitstream.
+//
+// If obj is a generic object, then explicits are the explicit type
+// arguments used to instantiate it (i.e., used to substitute the
+// object's own declared type parameters).
+func (w *writer) obj(obj types2.Object, explicits *types2.TypeList) {
+	w.objInfo(w.p.objInstIdx(obj, explicits, w.dict))
+}
+
+// objInfo writes a use of the given encoded object into the
+// bitstream.
+func (w *writer) objInfo(info objInfo) {
+	w.Sync(pkgbits.SyncObject)
+	w.Bool(false) // TODO(mdempsky): Remove; was derived func inst.
+	w.Reloc(pkgbits.RelocObj, info.idx)
+
+	w.Len(len(info.explicits))
+	for _, info := range info.explicits {
+		w.typInfo(info)
+	}
+}
+
+// objInstIdx returns the indices for an object and a corresponding
+// list of type arguments used to instantiate it, adding them to the
+// export data as needed.
+func (pw *pkgWriter) objInstIdx(obj types2.Object, explicits *types2.TypeList, dict *writerDict) objInfo {
+	explicitInfos := make([]typeInfo, explicits.Len())
+	for i := range explicitInfos {
+		explicitInfos[i] = pw.typIdx(explicits.At(i), dict)
+	}
+	return objInfo{idx: pw.objIdx(obj), explicits: explicitInfos}
+}
+
+// objIdx returns the index for the given Object, adding it to the
+// export data as needed.
+func (pw *pkgWriter) objIdx(obj types2.Object) pkgbits.Index {
+	// TODO(mdempsky): Validate that obj is a global object (or a local
+	// defined type, which we hoist to global scope anyway).
+
+	if idx, ok := pw.objsIdx[obj]; ok {
+		return idx
+	}
+
+	dict := &writerDict{
+		derivedIdx: make(map[types2.Type]pkgbits.Index),
+	}
+
+	if isDefinedType(obj) && obj.Pkg() == pw.curpkg {
+		decl, ok := pw.typDecls[obj.(*types2.TypeName)]
+		assert(ok)
+		dict.implicits = decl.implicits
+	}
+
+	// We encode objects into 4 elements across different sections, all
+	// sharing the same index:
+	//
+	// - RelocName has just the object's qualified name (i.e.,
+	//   Object.Pkg and Object.Name) and the CodeObj indicating what
+	//   specific type of Object it is (Var, Func, etc).
+	//
+	// - RelocObj has the remaining public details about the object,
+	//   relevant to go/types importers.
+	//
+	// - RelocObjExt has additional private details about the object,
+	//   which are only relevant to cmd/compile itself. This is
+	//   separated from RelocObj so that go/types importers are
+	//   unaffected by internal compiler changes.
+	//
+	// - RelocObjDict has public details about the object's type
+	//   parameters and derived type's used by the object. This is
+	//   separated to facilitate the eventual introduction of
+	//   shape-based stenciling.
+	//
+	// TODO(mdempsky): Re-evaluate whether RelocName still makes sense
+	// to keep separate from RelocObj.
+
+	w := pw.newWriter(pkgbits.RelocObj, pkgbits.SyncObject1)
+	wext := pw.newWriter(pkgbits.RelocObjExt, pkgbits.SyncObject1)
+	wname := pw.newWriter(pkgbits.RelocName, pkgbits.SyncObject1)
+	wdict := pw.newWriter(pkgbits.RelocObjDict, pkgbits.SyncObject1)
+
+	pw.objsIdx[obj] = w.Idx // break cycles
+	assert(wext.Idx == w.Idx)
+	assert(wname.Idx == w.Idx)
+	assert(wdict.Idx == w.Idx)
+
+	w.dict = dict
+	wext.dict = dict
+
+	code := w.doObj(wext, obj)
+	w.Flush()
+	wext.Flush()
+
+	wname.qualifiedIdent(obj)
+	wname.Code(code)
+	wname.Flush()
+
+	wdict.objDict(obj, w.dict)
+	wdict.Flush()
+
+	return w.Idx
+}
+
+// doObj writes the RelocObj definition for obj to w, and the
+// RelocObjExt definition to wext.
+func (w *writer) doObj(wext *writer, obj types2.Object) pkgbits.CodeObj {
+	if obj.Pkg() != w.p.curpkg {
+		return pkgbits.ObjStub
+	}
+
+	switch obj := obj.(type) {
+	default:
+		w.p.unexpected("object", obj)
+		panic("unreachable")
+
+	case *types2.Const:
+		w.pos(obj)
+		w.typ(obj.Type())
+		w.Value(obj.Val())
+		return pkgbits.ObjConst
+
+	case *types2.Func:
+		decl, ok := w.p.funDecls[obj]
+		assert(ok)
+		sig := obj.Type().(*types2.Signature)
+
+		w.pos(obj)
+		w.typeParamNames(sig.TypeParams())
+		w.signature(sig)
+		w.pos(decl)
+		wext.funcExt(obj)
+		return pkgbits.ObjFunc
+
+	case *types2.TypeName:
+		if obj.IsAlias() {
+			w.pos(obj)
+			w.typ(obj.Type())
+			return pkgbits.ObjAlias
+		}
+
+		named := obj.Type().(*types2.Named)
+		assert(named.TypeArgs() == nil)
+
+		w.pos(obj)
+		w.typeParamNames(named.TypeParams())
+		wext.typeExt(obj)
+		w.typ(named.Underlying())
+
+		w.Len(named.NumMethods())
+		for i := 0; i < named.NumMethods(); i++ {
+			w.method(wext, named.Method(i))
+		}
+
+		return pkgbits.ObjType
+
+	case *types2.Var:
+		w.pos(obj)
+		w.typ(obj.Type())
+		wext.varExt(obj)
+		return pkgbits.ObjVar
+	}
+}
+
+// objDict writes the dictionary needed for reading the given object.
+func (w *writer) objDict(obj types2.Object, dict *writerDict) {
+	// TODO(mdempsky): Split objDict into multiple entries? reader.go
+	// doesn't care about the type parameter bounds, and reader2.go
+	// doesn't care about referenced functions.
+
+	w.dict = dict // TODO(mdempsky): This is a bit sketchy.
+
+	w.Len(len(dict.implicits))
+
+	tparams := objTypeParams(obj)
+	ntparams := tparams.Len()
+	w.Len(ntparams)
+	for i := 0; i < ntparams; i++ {
+		w.typ(tparams.At(i).Constraint())
+	}
+
+	nderived := len(dict.derived)
+	w.Len(nderived)
+	for _, typ := range dict.derived {
+		w.Reloc(pkgbits.RelocType, typ.idx)
+		w.Bool(typ.needed)
+	}
+
+	// Write runtime dictionary information.
+	//
+	// N.B., the go/types importer reads up to the section, but doesn't
+	// read any further, so it's safe to change. (See TODO above.)
+
+	// For each type parameter, write out whether the constraint is a
+	// basic interface. This is used to determine how aggressively we
+	// can shape corresponding type arguments.
+	//
+	// This is somewhat redundant with writing out the full type
+	// parameter constraints above, but the compiler currently skips
+	// over those. Also, we don't care about the *declared* constraints,
+	// but how the type parameters are actually *used*. E.g., if a type
+	// parameter is constrained to `int | uint` but then never used in
+	// arithmetic/conversions/etc, we could shape those together.
+	for _, implicit := range dict.implicits {
+		tparam := implicit.Type().(*types2.TypeParam)
+		w.Bool(tparam.Underlying().(*types2.Interface).IsMethodSet())
+	}
+	for i := 0; i < ntparams; i++ {
+		tparam := tparams.At(i)
+		w.Bool(tparam.Underlying().(*types2.Interface).IsMethodSet())
+	}
+
+	w.Len(len(dict.typeParamMethodExprs))
+	for _, info := range dict.typeParamMethodExprs {
+		w.Len(info.typeParamIdx)
+		w.selectorInfo(info.methodInfo)
+	}
+
+	w.Len(len(dict.subdicts))
+	for _, info := range dict.subdicts {
+		w.objInfo(info)
+	}
+
+	w.Len(len(dict.rtypes))
+	for _, info := range dict.rtypes {
+		w.typInfo(info)
+	}
+
+	w.Len(len(dict.itabs))
+	for _, info := range dict.itabs {
+		w.typInfo(info.typ)
+		w.typInfo(info.iface)
+	}
+
+	assert(len(dict.derived) == nderived)
+}
+
+func (w *writer) typeParamNames(tparams *types2.TypeParamList) {
+	w.Sync(pkgbits.SyncTypeParamNames)
+
+	ntparams := tparams.Len()
+	for i := 0; i < ntparams; i++ {
+		tparam := tparams.At(i).Obj()
+		w.pos(tparam)
+		w.localIdent(tparam)
+	}
+}
+
+func (w *writer) method(wext *writer, meth *types2.Func) {
+	decl, ok := w.p.funDecls[meth]
+	assert(ok)
+	sig := meth.Type().(*types2.Signature)
+
+	w.Sync(pkgbits.SyncMethod)
+	w.pos(meth)
+	w.selector(meth)
+	w.typeParamNames(sig.RecvTypeParams())
+	w.param(sig.Recv())
+	w.signature(sig)
+
+	w.pos(decl) // XXX: Hack to workaround linker limitations.
+	wext.funcExt(meth)
+}
+
+// qualifiedIdent writes out the name of an object declared at package
+// scope. (For now, it's also used to refer to local defined types.)
+func (w *writer) qualifiedIdent(obj types2.Object) {
+	w.Sync(pkgbits.SyncSym)
+
+	name := obj.Name()
+	if isDefinedType(obj) && obj.Pkg() == w.p.curpkg {
+		decl, ok := w.p.typDecls[obj.(*types2.TypeName)]
+		assert(ok)
+		if decl.gen != 0 {
+			// For local defined types, we embed a scope-disambiguation
+			// number directly into their name. types.SplitVargenSuffix then
+			// knows to look for this.
+			//
+			// TODO(mdempsky): Find a better solution; this is terrible.
+			name = fmt.Sprintf("%s·%v", name, decl.gen)
+		}
+	}
+
+	w.pkg(obj.Pkg())
+	w.String(name)
+}
+
+// TODO(mdempsky): We should be able to omit pkg from both localIdent
+// and selector, because they should always be known from context.
+// However, past frustrations with this optimization in iexport make
+// me a little nervous to try it again.
+
+// localIdent writes the name of a locally declared object (i.e.,
+// objects that can only be accessed by non-qualified name, within the
+// context of a particular function).
+func (w *writer) localIdent(obj types2.Object) {
+	assert(!isGlobal(obj))
+	w.Sync(pkgbits.SyncLocalIdent)
+	w.pkg(obj.Pkg())
+	w.String(obj.Name())
+}
+
+// selector writes the name of a field or method (i.e., objects that
+// can only be accessed using selector expressions).
+func (w *writer) selector(obj types2.Object) {
+	w.selectorInfo(w.p.selectorIdx(obj))
+}
+
+func (w *writer) selectorInfo(info selectorInfo) {
+	w.Sync(pkgbits.SyncSelector)
+	w.pkgRef(info.pkgIdx)
+	w.StringRef(info.nameIdx)
+}
+
+func (pw *pkgWriter) selectorIdx(obj types2.Object) selectorInfo {
+	pkgIdx := pw.pkgIdx(obj.Pkg())
+	nameIdx := pw.StringIdx(obj.Name())
+	return selectorInfo{pkgIdx: pkgIdx, nameIdx: nameIdx}
+}
+
+// @@@ Compiler extensions
+
+func (w *writer) funcExt(obj *types2.Func) {
+	decl, ok := w.p.funDecls[obj]
+	assert(ok)
+
+	// TODO(mdempsky): Extend these pragma validation flags to account
+	// for generics. E.g., linkname probably doesn't make sense at
+	// least.
+
+	pragma := asPragmaFlag(decl.Pragma)
+	if pragma&ir.Systemstack != 0 && pragma&ir.Nosplit != 0 {
+		w.p.errorf(decl, "go:nosplit and go:systemstack cannot be combined")
+	}
+
+	if decl.Body != nil {
+		if pragma&ir.Noescape != 0 {
+			w.p.errorf(decl, "can only use //go:noescape with external func implementations")
+		}
+		if (pragma&ir.UintptrKeepAlive != 0 && pragma&ir.UintptrEscapes == 0) && pragma&ir.Nosplit == 0 {
+			// Stack growth can't handle uintptr arguments that may
+			// be pointers (as we don't know which are pointers
+			// when creating the stack map). Thus uintptrkeepalive
+			// functions (and all transitive callees) must be
+			// nosplit.
+			//
+			// N.B. uintptrescapes implies uintptrkeepalive but it
+			// is OK since the arguments must escape to the heap.
+			//
+			// TODO(prattmic): Add recursive nosplit check of callees.
+			// TODO(prattmic): Functions with no body (i.e.,
+			// assembly) must also be nosplit, but we can't check
+			// that here.
+			w.p.errorf(decl, "go:uintptrkeepalive requires go:nosplit")
+		}
+	} else {
+		if base.Flag.Complete || decl.Name.Value == "init" {
+			// Linknamed functions are allowed to have no body. Hopefully
+			// the linkname target has a body. See issue 23311.
+			if _, ok := w.p.linknames[obj]; !ok {
+				w.p.errorf(decl, "missing function body")
+			}
+		}
+	}
+
+	sig, block := obj.Type().(*types2.Signature), decl.Body
+	body, closureVars := w.p.bodyIdx(sig, block, w.dict)
+	assert(len(closureVars) == 0)
+
+	w.Sync(pkgbits.SyncFuncExt)
+	w.pragmaFlag(pragma)
+	w.linkname(obj)
+	w.Bool(false) // stub extension
+	w.Reloc(pkgbits.RelocBody, body)
+	w.Sync(pkgbits.SyncEOF)
+}
+
+func (w *writer) typeExt(obj *types2.TypeName) {
+	decl, ok := w.p.typDecls[obj]
+	assert(ok)
+
+	w.Sync(pkgbits.SyncTypeExt)
+
+	w.pragmaFlag(asPragmaFlag(decl.Pragma))
+
+	// No LSym.SymIdx info yet.
+	w.Int64(-1)
+	w.Int64(-1)
+}
+
+func (w *writer) varExt(obj *types2.Var) {
+	w.Sync(pkgbits.SyncVarExt)
+	w.linkname(obj)
+}
+
+func (w *writer) linkname(obj types2.Object) {
+	w.Sync(pkgbits.SyncLinkname)
+	w.Int64(-1)
+	w.String(w.p.linknames[obj])
+}
+
+func (w *writer) pragmaFlag(p ir.PragmaFlag) {
+	w.Sync(pkgbits.SyncPragma)
+	w.Int(int(p))
+}
+
+// @@@ Function bodies
+
+// bodyIdx returns the index for the given function body (specified by
+// block), adding it to the export data
+func (pw *pkgWriter) bodyIdx(sig *types2.Signature, block *syntax.BlockStmt, dict *writerDict) (idx pkgbits.Index, closureVars []posVar) {
+	w := pw.newWriter(pkgbits.RelocBody, pkgbits.SyncFuncBody)
+	w.sig = sig
+	w.dict = dict
+
+	w.funcargs(sig)
+	if w.Bool(block != nil) {
+		w.stmts(block.List)
+		w.pos(block.Rbrace)
+	}
+
+	return w.Flush(), w.closureVars
+}
+
+func (w *writer) funcargs(sig *types2.Signature) {
+	do := func(params *types2.Tuple, result bool) {
+		for i := 0; i < params.Len(); i++ {
+			w.funcarg(params.At(i), result)
+		}
+	}
+
+	if recv := sig.Recv(); recv != nil {
+		w.funcarg(recv, false)
+	}
+	do(sig.Params(), false)
+	do(sig.Results(), true)
+}
+
+func (w *writer) funcarg(param *types2.Var, result bool) {
+	if param.Name() != "" || result {
+		w.addLocal(param)
+	}
+}
+
+// addLocal records the declaration of a new local variable.
+func (w *writer) addLocal(obj *types2.Var) {
+	idx := len(w.localsIdx)
+
+	w.Sync(pkgbits.SyncAddLocal)
+	if w.p.SyncMarkers() {
+		w.Int(idx)
+	}
+	w.varDictIndex(obj)
+
+	if w.localsIdx == nil {
+		w.localsIdx = make(map[*types2.Var]int)
+	}
+	w.localsIdx[obj] = idx
+}
+
+// useLocal writes a reference to the given local or free variable
+// into the bitstream.
+func (w *writer) useLocal(pos syntax.Pos, obj *types2.Var) {
+	w.Sync(pkgbits.SyncUseObjLocal)
+
+	if idx, ok := w.localsIdx[obj]; w.Bool(ok) {
+		w.Len(idx)
+		return
+	}
+
+	idx, ok := w.closureVarsIdx[obj]
+	if !ok {
+		if w.closureVarsIdx == nil {
+			w.closureVarsIdx = make(map[*types2.Var]int)
+		}
+		idx = len(w.closureVars)
+		w.closureVars = append(w.closureVars, posVar{pos, obj})
+		w.closureVarsIdx[obj] = idx
+	}
+	w.Len(idx)
+}
+
+func (w *writer) openScope(pos syntax.Pos) {
+	w.Sync(pkgbits.SyncOpenScope)
+	w.pos(pos)
+}
+
+func (w *writer) closeScope(pos syntax.Pos) {
+	w.Sync(pkgbits.SyncCloseScope)
+	w.pos(pos)
+	w.closeAnotherScope()
+}
+
+func (w *writer) closeAnotherScope() {
+	w.Sync(pkgbits.SyncCloseAnotherScope)
+}
+
+// @@@ Statements
+
+// stmt writes the given statement into the function body bitstream.
+func (w *writer) stmt(stmt syntax.Stmt) {
+	var stmts []syntax.Stmt
+	if stmt != nil {
+		stmts = []syntax.Stmt{stmt}
+	}
+	w.stmts(stmts)
+}
+
+func (w *writer) stmts(stmts []syntax.Stmt) {
+	w.Sync(pkgbits.SyncStmts)
+	for _, stmt := range stmts {
+		w.stmt1(stmt)
+	}
+	w.Code(stmtEnd)
+	w.Sync(pkgbits.SyncStmtsEnd)
+}
+
+func (w *writer) stmt1(stmt syntax.Stmt) {
+	switch stmt := stmt.(type) {
+	default:
+		w.p.unexpected("statement", stmt)
+
+	case nil, *syntax.EmptyStmt:
+		return
+
+	case *syntax.AssignStmt:
+		switch {
+		case stmt.Rhs == nil:
+			w.Code(stmtIncDec)
+			w.op(binOps[stmt.Op])
+			w.expr(stmt.Lhs)
+			w.pos(stmt)
+
+		case stmt.Op != 0 && stmt.Op != syntax.Def:
+			w.Code(stmtAssignOp)
+			w.op(binOps[stmt.Op])
+			w.expr(stmt.Lhs)
+			w.pos(stmt)
+
+			var typ types2.Type
+			if stmt.Op != syntax.Shl && stmt.Op != syntax.Shr {
+				typ = w.p.typeOf(stmt.Lhs)
+			}
+			w.implicitConvExpr(typ, stmt.Rhs)
+
+		default:
+			w.assignStmt(stmt, stmt.Lhs, stmt.Rhs)
+		}
+
+	case *syntax.BlockStmt:
+		w.Code(stmtBlock)
+		w.blockStmt(stmt)
+
+	case *syntax.BranchStmt:
+		w.Code(stmtBranch)
+		w.pos(stmt)
+		w.op(branchOps[stmt.Tok])
+		w.optLabel(stmt.Label)
+
+	case *syntax.CallStmt:
+		w.Code(stmtCall)
+		w.pos(stmt)
+		w.op(callOps[stmt.Tok])
+		w.expr(stmt.Call)
+
+	case *syntax.DeclStmt:
+		for _, decl := range stmt.DeclList {
+			w.declStmt(decl)
+		}
+
+	case *syntax.ExprStmt:
+		w.Code(stmtExpr)
+		w.expr(stmt.X)
+
+	case *syntax.ForStmt:
+		w.Code(stmtFor)
+		w.forStmt(stmt)
+
+	case *syntax.IfStmt:
+		w.Code(stmtIf)
+		w.ifStmt(stmt)
+
+	case *syntax.LabeledStmt:
+		w.Code(stmtLabel)
+		w.pos(stmt)
+		w.label(stmt.Label)
+		w.stmt1(stmt.Stmt)
+
+	case *syntax.ReturnStmt:
+		w.Code(stmtReturn)
+		w.pos(stmt)
+
+		resultTypes := w.sig.Results()
+		dstType := func(i int) types2.Type {
+			return resultTypes.At(i).Type()
+		}
+		w.multiExpr(stmt, dstType, unpackListExpr(stmt.Results))
+
+	case *syntax.SelectStmt:
+		w.Code(stmtSelect)
+		w.selectStmt(stmt)
+
+	case *syntax.SendStmt:
+		chanType := types2.CoreType(w.p.typeOf(stmt.Chan)).(*types2.Chan)
+
+		w.Code(stmtSend)
+		w.pos(stmt)
+		w.expr(stmt.Chan)
+		w.implicitConvExpr(chanType.Elem(), stmt.Value)
+
+	case *syntax.SwitchStmt:
+		w.Code(stmtSwitch)
+		w.switchStmt(stmt)
+	}
+}
+
+func (w *writer) assignList(expr syntax.Expr) {
+	exprs := unpackListExpr(expr)
+	w.Len(len(exprs))
+
+	for _, expr := range exprs {
+		w.assign(expr)
+	}
+}
+
+func (w *writer) assign(expr syntax.Expr) {
+	expr = unparen(expr)
+
+	if name, ok := expr.(*syntax.Name); ok {
+		if name.Value == "_" {
+			w.Code(assignBlank)
+			return
+		}
+
+		if obj, ok := w.p.info.Defs[name]; ok {
+			obj := obj.(*types2.Var)
+
+			w.Code(assignDef)
+			w.pos(obj)
+			w.localIdent(obj)
+			w.typ(obj.Type())
+
+			// TODO(mdempsky): Minimize locals index size by deferring
+			// this until the variables actually come into scope.
+			w.addLocal(obj)
+			return
+		}
+	}
+
+	w.Code(assignExpr)
+	w.expr(expr)
+}
+
+func (w *writer) declStmt(decl syntax.Decl) {
+	switch decl := decl.(type) {
+	default:
+		w.p.unexpected("declaration", decl)
+
+	case *syntax.ConstDecl, *syntax.TypeDecl:
+
+	case *syntax.VarDecl:
+		w.assignStmt(decl, namesAsExpr(decl.NameList), decl.Values)
+	}
+}
+
+// assignStmt writes out an assignment for "lhs = rhs".
+func (w *writer) assignStmt(pos poser, lhs0, rhs0 syntax.Expr) {
+	lhs := unpackListExpr(lhs0)
+	rhs := unpackListExpr(rhs0)
+
+	w.Code(stmtAssign)
+	w.pos(pos)
+
+	// As if w.assignList(lhs0).
+	w.Len(len(lhs))
+	for _, expr := range lhs {
+		w.assign(expr)
+	}
+
+	dstType := func(i int) types2.Type {
+		dst := lhs[i]
+
+		// Finding dstType is somewhat involved, because for VarDecl
+		// statements, the Names are only added to the info.{Defs,Uses}
+		// maps, not to info.Types.
+		if name, ok := unparen(dst).(*syntax.Name); ok {
+			if name.Value == "_" {
+				return nil // ok: no implicit conversion
+			} else if def, ok := w.p.info.Defs[name].(*types2.Var); ok {
+				return def.Type()
+			} else if use, ok := w.p.info.Uses[name].(*types2.Var); ok {
+				return use.Type()
+			} else {
+				w.p.fatalf(dst, "cannot find type of destination object: %v", dst)
+			}
+		}
+
+		return w.p.typeOf(dst)
+	}
+
+	w.multiExpr(pos, dstType, rhs)
+}
+
+func (w *writer) blockStmt(stmt *syntax.BlockStmt) {
+	w.Sync(pkgbits.SyncBlockStmt)
+	w.openScope(stmt.Pos())
+	w.stmts(stmt.List)
+	w.closeScope(stmt.Rbrace)
+}
+
+func (w *writer) forStmt(stmt *syntax.ForStmt) {
+	w.Sync(pkgbits.SyncForStmt)
+	w.openScope(stmt.Pos())
+
+	if rang, ok := stmt.Init.(*syntax.RangeClause); w.Bool(ok) {
+		w.pos(rang)
+		w.assignList(rang.Lhs)
+		w.expr(rang.X)
+
+		xtyp := w.p.typeOf(rang.X)
+		if _, isMap := types2.CoreType(xtyp).(*types2.Map); isMap {
+			w.rtype(xtyp)
+		}
+		{
+			lhs := unpackListExpr(rang.Lhs)
+			assign := func(i int, src types2.Type) {
+				if i >= len(lhs) {
+					return
+				}
+				dst := unparen(lhs[i])
+				if name, ok := dst.(*syntax.Name); ok && name.Value == "_" {
+					return
+				}
+
+				var dstType types2.Type
+				if rang.Def {
+					// For `:=` assignments, the LHS names only appear in Defs,
+					// not Types (as used by typeOf).
+					dstType = w.p.info.Defs[dst.(*syntax.Name)].(*types2.Var).Type()
+				} else {
+					dstType = w.p.typeOf(dst)
+				}
+
+				w.convRTTI(src, dstType)
+			}
+
+			keyType, valueType := w.p.rangeTypes(rang.X)
+			assign(0, keyType)
+			assign(1, valueType)
+		}
+
+	} else {
+		w.pos(stmt)
+		w.stmt(stmt.Init)
+		w.optExpr(stmt.Cond)
+		w.stmt(stmt.Post)
+	}
+
+	w.blockStmt(stmt.Body)
+	w.closeAnotherScope()
+}
+
+// rangeTypes returns the types of values produced by ranging over
+// expr.
+func (pw *pkgWriter) rangeTypes(expr syntax.Expr) (key, value types2.Type) {
+	typ := pw.typeOf(expr)
+	switch typ := types2.CoreType(typ).(type) {
+	case *types2.Pointer: // must be pointer to array
+		return types2.Typ[types2.Int], types2.CoreType(typ.Elem()).(*types2.Array).Elem()
+	case *types2.Array:
+		return types2.Typ[types2.Int], typ.Elem()
+	case *types2.Slice:
+		return types2.Typ[types2.Int], typ.Elem()
+	case *types2.Basic:
+		if typ.Info()&types2.IsString != 0 {
+			return types2.Typ[types2.Int], runeTypeName.Type()
+		}
+	case *types2.Map:
+		return typ.Key(), typ.Elem()
+	case *types2.Chan:
+		return typ.Elem(), nil
+	}
+	pw.fatalf(expr, "unexpected range type: %v", typ)
+	panic("unreachable")
+}
+
+func (w *writer) ifStmt(stmt *syntax.IfStmt) {
+	w.Sync(pkgbits.SyncIfStmt)
+	w.openScope(stmt.Pos())
+	w.pos(stmt)
+	w.stmt(stmt.Init)
+	w.expr(stmt.Cond)
+	w.blockStmt(stmt.Then)
+	w.stmt(stmt.Else)
+	w.closeAnotherScope()
+}
+
+func (w *writer) selectStmt(stmt *syntax.SelectStmt) {
+	w.Sync(pkgbits.SyncSelectStmt)
+
+	w.pos(stmt)
+	w.Len(len(stmt.Body))
+	for i, clause := range stmt.Body {
+		if i > 0 {
+			w.closeScope(clause.Pos())
+		}
+		w.openScope(clause.Pos())
+
+		w.pos(clause)
+		w.stmt(clause.Comm)
+		w.stmts(clause.Body)
+	}
+	if len(stmt.Body) > 0 {
+		w.closeScope(stmt.Rbrace)
+	}
+}
+
+func (w *writer) switchStmt(stmt *syntax.SwitchStmt) {
+	w.Sync(pkgbits.SyncSwitchStmt)
+
+	w.openScope(stmt.Pos())
+	w.pos(stmt)
+	w.stmt(stmt.Init)
+
+	var iface, tagType types2.Type
+	if guard, ok := stmt.Tag.(*syntax.TypeSwitchGuard); w.Bool(ok) {
+		iface = w.p.typeOf(guard.X)
+
+		w.pos(guard)
+		if tag := guard.Lhs; w.Bool(tag != nil) {
+			w.pos(tag)
+
+			// Like w.localIdent, but we don't have a types2.Object.
+			w.Sync(pkgbits.SyncLocalIdent)
+			w.pkg(w.p.curpkg)
+			w.String(tag.Value)
+		}
+		w.expr(guard.X)
+	} else {
+		tag := stmt.Tag
+
+		if tag != nil {
+			tagType = w.p.typeOf(tag)
+		} else {
+			tagType = types2.Typ[types2.Bool]
+		}
+
+		// Walk is going to emit comparisons between the tag value and
+		// each case expression, and we want these comparisons to always
+		// have the same type. If there are any case values that can't be
+		// converted to the tag value's type, then convert everything to
+		// `any` instead.
+	Outer:
+		for _, clause := range stmt.Body {
+			for _, cas := range unpackListExpr(clause.Cases) {
+				if casType := w.p.typeOf(cas); !types2.AssignableTo(casType, tagType) {
+					tagType = types2.NewInterfaceType(nil, nil)
+					break Outer
+				}
+			}
+		}
+
+		if w.Bool(tag != nil) {
+			w.implicitConvExpr(tagType, tag)
+		}
+	}
+
+	w.Len(len(stmt.Body))
+	for i, clause := range stmt.Body {
+		if i > 0 {
+			w.closeScope(clause.Pos())
+		}
+		w.openScope(clause.Pos())
+
+		w.pos(clause)
+
+		cases := unpackListExpr(clause.Cases)
+		if iface != nil {
+			w.Len(len(cases))
+			for _, cas := range cases {
+				if w.Bool(isNil(w.p, cas)) {
+					continue
+				}
+				w.exprType(iface, cas)
+			}
+		} else {
+			// As if w.exprList(clause.Cases),
+			// but with implicit conversions to tagType.
+
+			w.Sync(pkgbits.SyncExprList)
+			w.Sync(pkgbits.SyncExprs)
+			w.Len(len(cases))
+			for _, cas := range cases {
+				w.implicitConvExpr(tagType, cas)
+			}
+		}
+
+		if obj, ok := w.p.info.Implicits[clause]; ok {
+			// TODO(mdempsky): These pos details are quirkish, but also
+			// necessary so the variable's position is correct for DWARF
+			// scope assignment later. It would probably be better for us to
+			// instead just set the variable's DWARF scoping info earlier so
+			// we can give it the correct position information.
+			pos := clause.Pos()
+			if typs := unpackListExpr(clause.Cases); len(typs) != 0 {
+				pos = typeExprEndPos(typs[len(typs)-1])
+			}
+			w.pos(pos)
+
+			obj := obj.(*types2.Var)
+			w.typ(obj.Type())
+			w.addLocal(obj)
+		}
+
+		w.stmts(clause.Body)
+	}
+	if len(stmt.Body) > 0 {
+		w.closeScope(stmt.Rbrace)
+	}
+
+	w.closeScope(stmt.Rbrace)
+}
+
+func (w *writer) label(label *syntax.Name) {
+	w.Sync(pkgbits.SyncLabel)
+
+	// TODO(mdempsky): Replace label strings with dense indices.
+	w.String(label.Value)
+}
+
+func (w *writer) optLabel(label *syntax.Name) {
+	w.Sync(pkgbits.SyncOptLabel)
+	if w.Bool(label != nil) {
+		w.label(label)
+	}
+}
+
+// @@@ Expressions
+
+// expr writes the given expression into the function body bitstream.
+func (w *writer) expr(expr syntax.Expr) {
+	base.Assertf(expr != nil, "missing expression")
+
+	expr = unparen(expr) // skip parens; unneeded after typecheck
+
+	obj, inst := lookupObj(w.p, expr)
+	targs := inst.TypeArgs
+
+	if tv, ok := w.p.maybeTypeAndValue(expr); ok {
+		if tv.IsType() {
+			w.p.fatalf(expr, "unexpected type expression %v", syntax.String(expr))
+		}
+
+		if tv.Value != nil {
+			w.Code(exprConst)
+			w.pos(expr)
+			typ := idealType(tv)
+			assert(typ != nil)
+			w.typ(typ)
+			w.Value(tv.Value)
+
+			// TODO(mdempsky): These details are only important for backend
+			// diagnostics. Explore writing them out separately.
+			w.op(constExprOp(expr))
+			w.String(syntax.String(expr))
+			return
+		}
+
+		if _, isNil := obj.(*types2.Nil); isNil {
+			w.Code(exprNil)
+			w.pos(expr)
+			w.typ(tv.Type)
+			return
+		}
+
+		// With shape types (and particular pointer shaping), we may have
+		// an expression of type "go.shape.*uint8", but need to reshape it
+		// to another shape-identical type to allow use in field
+		// selection, indexing, etc.
+		if typ := tv.Type; !tv.IsBuiltin() && !isTuple(typ) && !isUntyped(typ) {
+			w.Code(exprReshape)
+			w.typ(typ)
+			// fallthrough
+		}
+	}
+
+	if obj != nil {
+		if targs.Len() != 0 {
+			obj := obj.(*types2.Func)
+
+			w.Code(exprFuncInst)
+			w.pos(expr)
+			w.funcInst(obj, targs)
+			return
+		}
+
+		if isGlobal(obj) {
+			w.Code(exprGlobal)
+			w.obj(obj, nil)
+			return
+		}
+
+		obj := obj.(*types2.Var)
+		assert(!obj.IsField())
+
+		w.Code(exprLocal)
+		w.useLocal(expr.Pos(), obj)
+		return
+	}
+
+	switch expr := expr.(type) {
+	default:
+		w.p.unexpected("expression", expr)
+
+	case *syntax.CompositeLit:
+		w.Code(exprCompLit)
+		w.compLit(expr)
+
+	case *syntax.FuncLit:
+		w.Code(exprFuncLit)
+		w.funcLit(expr)
+
+	case *syntax.SelectorExpr:
+		sel, ok := w.p.info.Selections[expr]
+		assert(ok)
+
+		switch sel.Kind() {
+		default:
+			w.p.fatalf(expr, "unexpected selection kind: %v", sel.Kind())
+
+		case types2.FieldVal:
+			w.Code(exprFieldVal)
+			w.expr(expr.X)
+			w.pos(expr)
+			w.selector(sel.Obj())
+
+		case types2.MethodVal:
+			w.Code(exprMethodVal)
+			typ := w.recvExpr(expr, sel)
+			w.pos(expr)
+			w.methodExpr(expr, typ, sel)
+
+		case types2.MethodExpr:
+			w.Code(exprMethodExpr)
+
+			tv := w.p.typeAndValue(expr.X)
+			assert(tv.IsType())
+
+			index := sel.Index()
+			implicits := index[:len(index)-1]
+
+			typ := tv.Type
+			w.typ(typ)
+
+			w.Len(len(implicits))
+			for _, ix := range implicits {
+				w.Len(ix)
+				typ = deref2(typ).Underlying().(*types2.Struct).Field(ix).Type()
+			}
+
+			recv := sel.Obj().(*types2.Func).Type().(*types2.Signature).Recv().Type()
+			if w.Bool(isPtrTo(typ, recv)) { // need deref
+				typ = recv
+			} else if w.Bool(isPtrTo(recv, typ)) { // need addr
+				typ = recv
+			}
+
+			w.pos(expr)
+			w.methodExpr(expr, typ, sel)
+		}
+
+	case *syntax.IndexExpr:
+		_ = w.p.typeOf(expr.Index) // ensure this is an index expression, not an instantiation
+
+		xtyp := w.p.typeOf(expr.X)
+
+		var keyType types2.Type
+		if mapType, ok := types2.CoreType(xtyp).(*types2.Map); ok {
+			keyType = mapType.Key()
+		}
+
+		w.Code(exprIndex)
+		w.expr(expr.X)
+		w.pos(expr)
+		w.implicitConvExpr(keyType, expr.Index)
+		if keyType != nil {
+			w.rtype(xtyp)
+		}
+
+	case *syntax.SliceExpr:
+		w.Code(exprSlice)
+		w.expr(expr.X)
+		w.pos(expr)
+		for _, n := range &expr.Index {
+			w.optExpr(n)
+		}
+
+	case *syntax.AssertExpr:
+		iface := w.p.typeOf(expr.X)
+
+		w.Code(exprAssert)
+		w.expr(expr.X)
+		w.pos(expr)
+		w.exprType(iface, expr.Type)
+		w.rtype(iface)
+
+	case *syntax.Operation:
+		if expr.Y == nil {
+			w.Code(exprUnaryOp)
+			w.op(unOps[expr.Op])
+			w.pos(expr)
+			w.expr(expr.X)
+			break
+		}
+
+		var commonType types2.Type
+		switch expr.Op {
+		case syntax.Shl, syntax.Shr:
+			// ok: operands are allowed to have different types
+		default:
+			xtyp := w.p.typeOf(expr.X)
+			ytyp := w.p.typeOf(expr.Y)
+			switch {
+			case types2.AssignableTo(xtyp, ytyp):
+				commonType = ytyp
+			case types2.AssignableTo(ytyp, xtyp):
+				commonType = xtyp
+			default:
+				w.p.fatalf(expr, "failed to find common type between %v and %v", xtyp, ytyp)
+			}
+		}
+
+		w.Code(exprBinaryOp)
+		w.op(binOps[expr.Op])
+		w.implicitConvExpr(commonType, expr.X)
+		w.pos(expr)
+		w.implicitConvExpr(commonType, expr.Y)
+
+	case *syntax.CallExpr:
+		tv := w.p.typeAndValue(expr.Fun)
+		if tv.IsType() {
+			assert(len(expr.ArgList) == 1)
+			assert(!expr.HasDots)
+			w.convertExpr(tv.Type, expr.ArgList[0], false)
+			break
+		}
+
+		var rtype types2.Type
+		if tv.IsBuiltin() {
+			switch obj, _ := lookupObj(w.p, expr.Fun); obj.Name() {
+			case "make":
+				assert(len(expr.ArgList) >= 1)
+				assert(!expr.HasDots)
+
+				w.Code(exprMake)
+				w.pos(expr)
+				w.exprType(nil, expr.ArgList[0])
+				w.exprs(expr.ArgList[1:])
+
+				typ := w.p.typeOf(expr)
+				switch coreType := types2.CoreType(typ).(type) {
+				default:
+					w.p.fatalf(expr, "unexpected core type: %v", coreType)
+				case *types2.Chan:
+					w.rtype(typ)
+				case *types2.Map:
+					w.rtype(typ)
+				case *types2.Slice:
+					w.rtype(sliceElem(typ))
+				}
+
+				return
+
+			case "new":
+				assert(len(expr.ArgList) == 1)
+				assert(!expr.HasDots)
+
+				w.Code(exprNew)
+				w.pos(expr)
+				w.exprType(nil, expr.ArgList[0])
+				return
+
+			case "append":
+				rtype = sliceElem(w.p.typeOf(expr))
+			case "copy":
+				typ := w.p.typeOf(expr.ArgList[0])
+				if tuple, ok := typ.(*types2.Tuple); ok { // "copy(g())"
+					typ = tuple.At(0).Type()
+				}
+				rtype = sliceElem(typ)
+			case "delete":
+				typ := w.p.typeOf(expr.ArgList[0])
+				if tuple, ok := typ.(*types2.Tuple); ok { // "delete(g())"
+					typ = tuple.At(0).Type()
+				}
+				rtype = typ
+			case "Slice":
+				rtype = sliceElem(w.p.typeOf(expr))
+			}
+		}
+
+		writeFunExpr := func() {
+			fun := unparen(expr.Fun)
+
+			if selector, ok := fun.(*syntax.SelectorExpr); ok {
+				if sel, ok := w.p.info.Selections[selector]; ok && sel.Kind() == types2.MethodVal {
+					w.Bool(true) // method call
+					typ := w.recvExpr(selector, sel)
+					w.methodExpr(selector, typ, sel)
+					return
+				}
+			}
+
+			w.Bool(false) // not a method call (i.e., normal function call)
+
+			if obj, inst := lookupObj(w.p, fun); w.Bool(obj != nil && inst.TypeArgs.Len() != 0) {
+				obj := obj.(*types2.Func)
+
+				w.pos(fun)
+				w.funcInst(obj, inst.TypeArgs)
+				return
+			}
+
+			w.expr(fun)
+		}
+
+		sigType := types2.CoreType(tv.Type).(*types2.Signature)
+		paramTypes := sigType.Params()
+
+		w.Code(exprCall)
+		writeFunExpr()
+		w.pos(expr)
+
+		paramType := func(i int) types2.Type {
+			if sigType.Variadic() && !expr.HasDots && i >= paramTypes.Len()-1 {
+				return paramTypes.At(paramTypes.Len() - 1).Type().(*types2.Slice).Elem()
+			}
+			return paramTypes.At(i).Type()
+		}
+
+		w.multiExpr(expr, paramType, expr.ArgList)
+		w.Bool(expr.HasDots)
+		if rtype != nil {
+			w.rtype(rtype)
+		}
+	}
+}
+
+func sliceElem(typ types2.Type) types2.Type {
+	return types2.CoreType(typ).(*types2.Slice).Elem()
+}
+
+func (w *writer) optExpr(expr syntax.Expr) {
+	if w.Bool(expr != nil) {
+		w.expr(expr)
+	}
+}
+
+// recvExpr writes out expr.X, but handles any implicit addressing,
+// dereferencing, and field selections appropriate for the method
+// selection.
+func (w *writer) recvExpr(expr *syntax.SelectorExpr, sel *types2.Selection) types2.Type {
+	index := sel.Index()
+	implicits := index[:len(index)-1]
+
+	w.Code(exprRecv)
+	w.expr(expr.X)
+	w.pos(expr)
+	w.Len(len(implicits))
+
+	typ := w.p.typeOf(expr.X)
+	for _, ix := range implicits {
+		typ = deref2(typ).Underlying().(*types2.Struct).Field(ix).Type()
+		w.Len(ix)
+	}
+
+	recv := sel.Obj().(*types2.Func).Type().(*types2.Signature).Recv().Type()
+	if w.Bool(isPtrTo(typ, recv)) { // needs deref
+		typ = recv
+	} else if w.Bool(isPtrTo(recv, typ)) { // needs addr
+		typ = recv
+	}
+
+	return typ
+}
+
+// funcInst writes a reference to an instantiated function.
+func (w *writer) funcInst(obj *types2.Func, targs *types2.TypeList) {
+	info := w.p.objInstIdx(obj, targs, w.dict)
+
+	// Type arguments list contains derived types; we can emit a static
+	// call to the shaped function, but need to dynamically compute the
+	// runtime dictionary pointer.
+	if w.Bool(info.anyDerived()) {
+		w.Len(w.dict.subdictIdx(info))
+		return
+	}
+
+	// Type arguments list is statically known; we can emit a static
+	// call with a statically reference to the respective runtime
+	// dictionary.
+	w.objInfo(info)
+}
+
+// methodExpr writes out a reference to the method selected by
+// expr. sel should be the corresponding types2.Selection, and recv
+// the type produced after any implicit addressing, dereferencing, and
+// field selection. (Note: recv might differ from sel.Obj()'s receiver
+// parameter in the case of interface types, and is needed for
+// handling type parameter methods.)
+func (w *writer) methodExpr(expr *syntax.SelectorExpr, recv types2.Type, sel *types2.Selection) {
+	fun := sel.Obj().(*types2.Func)
+	sig := fun.Type().(*types2.Signature)
+
+	w.typ(recv)
+	w.typ(sig)
+	w.pos(expr)
+	w.selector(fun)
+
+	// Method on a type parameter. These require an indirect call
+	// through the current function's runtime dictionary.
+	if typeParam, ok := recv.(*types2.TypeParam); w.Bool(ok) {
+		typeParamIdx := w.dict.typeParamIndex(typeParam)
+		methodInfo := w.p.selectorIdx(fun)
+
+		w.Len(w.dict.typeParamMethodExprIdx(typeParamIdx, methodInfo))
+		return
+	}
+
+	if isInterface(recv) != isInterface(sig.Recv().Type()) {
+		w.p.fatalf(expr, "isInterface inconsistency: %v and %v", recv, sig.Recv().Type())
+	}
+
+	if !isInterface(recv) {
+		if named, ok := deref2(recv).(*types2.Named); ok {
+			obj, targs := splitNamed(named)
+			info := w.p.objInstIdx(obj, targs, w.dict)
+
+			// Method on a derived receiver type. These can be handled by a
+			// static call to the shaped method, but require dynamically
+			// looking up the appropriate dictionary argument in the current
+			// function's runtime dictionary.
+			if w.p.hasImplicitTypeParams(obj) || info.anyDerived() {
+				w.Bool(true) // dynamic subdictionary
+				w.Len(w.dict.subdictIdx(info))
+				return
+			}
+
+			// Method on a fully known receiver type. These can be handled
+			// by a static call to the shaped method, and with a static
+			// reference to the receiver type's dictionary.
+			if targs.Len() != 0 {
+				w.Bool(false) // no dynamic subdictionary
+				w.Bool(true)  // static dictionary
+				w.objInfo(info)
+				return
+			}
+		}
+	}
+
+	w.Bool(false) // no dynamic subdictionary
+	w.Bool(false) // no static dictionary
+}
+
+// multiExpr writes a sequence of expressions, where the i'th value is
+// implicitly converted to dstType(i). It also handles when exprs is a
+// single, multi-valued expression (e.g., the multi-valued argument in
+// an f(g()) call, or the RHS operand in a comma-ok assignment).
+func (w *writer) multiExpr(pos poser, dstType func(int) types2.Type, exprs []syntax.Expr) {
+	w.Sync(pkgbits.SyncMultiExpr)
+
+	if len(exprs) == 1 {
+		expr := exprs[0]
+		if tuple, ok := w.p.typeOf(expr).(*types2.Tuple); ok {
+			assert(tuple.Len() > 1)
+			w.Bool(true) // N:1 assignment
+			w.pos(pos)
+			w.expr(expr)
+
+			w.Len(tuple.Len())
+			for i := 0; i < tuple.Len(); i++ {
+				src := tuple.At(i).Type()
+				// TODO(mdempsky): Investigate not writing src here. I think
+				// the reader should be able to infer it from expr anyway.
+				w.typ(src)
+				if dst := dstType(i); w.Bool(dst != nil && !types2.Identical(src, dst)) {
+					if src == nil || dst == nil {
+						w.p.fatalf(pos, "src is %v, dst is %v", src, dst)
+					}
+					if !types2.AssignableTo(src, dst) {
+						w.p.fatalf(pos, "%v is not assignable to %v", src, dst)
+					}
+					w.typ(dst)
+					w.convRTTI(src, dst)
+				}
+			}
+			return
+		}
+	}
+
+	w.Bool(false) // N:N assignment
+	w.Len(len(exprs))
+	for i, expr := range exprs {
+		w.implicitConvExpr(dstType(i), expr)
+	}
+}
+
+// implicitConvExpr is like expr, but if dst is non-nil and different
+// from expr's type, then an implicit conversion operation is inserted
+// at expr's position.
+func (w *writer) implicitConvExpr(dst types2.Type, expr syntax.Expr) {
+	w.convertExpr(dst, expr, true)
+}
+
+func (w *writer) convertExpr(dst types2.Type, expr syntax.Expr, implicit bool) {
+	src := w.p.typeOf(expr)
+
+	// Omit implicit no-op conversions.
+	identical := dst == nil || types2.Identical(src, dst)
+	if implicit && identical {
+		w.expr(expr)
+		return
+	}
+
+	if implicit && !types2.AssignableTo(src, dst) {
+		w.p.fatalf(expr, "%v is not assignable to %v", src, dst)
+	}
+
+	w.Code(exprConvert)
+	w.Bool(implicit)
+	w.typ(dst)
+	w.pos(expr)
+	w.convRTTI(src, dst)
+	w.Bool(isTypeParam(dst))
+	w.Bool(identical)
+	w.expr(expr)
+}
+
+func (w *writer) compLit(lit *syntax.CompositeLit) {
+	typ := w.p.typeOf(lit)
+
+	w.Sync(pkgbits.SyncCompLit)
+	w.pos(lit)
+	w.typ(typ)
+
+	if ptr, ok := types2.CoreType(typ).(*types2.Pointer); ok {
+		typ = ptr.Elem()
+	}
+	var keyType, elemType types2.Type
+	var structType *types2.Struct
+	switch typ0 := typ; typ := types2.CoreType(typ).(type) {
+	default:
+		w.p.fatalf(lit, "unexpected composite literal type: %v", typ)
+	case *types2.Array:
+		elemType = typ.Elem()
+	case *types2.Map:
+		w.rtype(typ0)
+		keyType, elemType = typ.Key(), typ.Elem()
+	case *types2.Slice:
+		elemType = typ.Elem()
+	case *types2.Struct:
+		structType = typ
+	}
+
+	w.Len(len(lit.ElemList))
+	for i, elem := range lit.ElemList {
+		elemType := elemType
+		if structType != nil {
+			if kv, ok := elem.(*syntax.KeyValueExpr); ok {
+				// use position of expr.Key rather than of elem (which has position of ':')
+				w.pos(kv.Key)
+				i = fieldIndex(w.p.info, structType, kv.Key.(*syntax.Name))
+				elem = kv.Value
+			} else {
+				w.pos(elem)
+			}
+			elemType = structType.Field(i).Type()
+			w.Len(i)
+		} else {
+			if kv, ok := elem.(*syntax.KeyValueExpr); w.Bool(ok) {
+				// use position of expr.Key rather than of elem (which has position of ':')
+				w.pos(kv.Key)
+				w.implicitConvExpr(keyType, kv.Key)
+				elem = kv.Value
+			}
+		}
+		w.pos(elem)
+		w.implicitConvExpr(elemType, elem)
+	}
+}
+
+func (w *writer) funcLit(expr *syntax.FuncLit) {
+	sig := w.p.typeOf(expr).(*types2.Signature)
+
+	body, closureVars := w.p.bodyIdx(sig, expr.Body, w.dict)
+
+	w.Sync(pkgbits.SyncFuncLit)
+	w.pos(expr)
+	w.signature(sig)
+
+	w.Len(len(closureVars))
+	for _, cv := range closureVars {
+		w.pos(cv.pos)
+		w.useLocal(cv.pos, cv.var_)
+	}
+
+	w.Reloc(pkgbits.RelocBody, body)
+}
+
+type posVar struct {
+	pos  syntax.Pos
+	var_ *types2.Var
+}
+
+func (w *writer) exprList(expr syntax.Expr) {
+	w.Sync(pkgbits.SyncExprList)
+	w.exprs(unpackListExpr(expr))
+}
+
+func (w *writer) exprs(exprs []syntax.Expr) {
+	w.Sync(pkgbits.SyncExprs)
+	w.Len(len(exprs))
+	for _, expr := range exprs {
+		w.expr(expr)
+	}
+}
+
+// rtype writes information so that the reader can construct an
+// expression of type *runtime._type representing typ.
+func (w *writer) rtype(typ types2.Type) {
+	typ = types2.Default(typ)
+
+	info := w.p.typIdx(typ, w.dict)
+	w.rtypeInfo(info)
+}
+
+func (w *writer) rtypeInfo(info typeInfo) {
+	w.Sync(pkgbits.SyncRType)
+
+	if w.Bool(info.derived) {
+		w.Len(w.dict.rtypeIdx(info))
+	} else {
+		w.typInfo(info)
+	}
+}
+
+// varDictIndex writes out information for populating DictIndex for
+// the ir.Name that will represent obj.
+func (w *writer) varDictIndex(obj *types2.Var) {
+	info := w.p.typIdx(obj.Type(), w.dict)
+	if w.Bool(info.derived) {
+		w.Len(w.dict.rtypeIdx(info))
+	}
+}
+
+func isUntyped(typ types2.Type) bool {
+	basic, ok := typ.(*types2.Basic)
+	return ok && basic.Info()&types2.IsUntyped != 0
+}
+
+func isTuple(typ types2.Type) bool {
+	_, ok := typ.(*types2.Tuple)
+	return ok
+}
+
+func (w *writer) itab(typ, iface types2.Type) {
+	typ = types2.Default(typ)
+	iface = types2.Default(iface)
+
+	typInfo := w.p.typIdx(typ, w.dict)
+	ifaceInfo := w.p.typIdx(iface, w.dict)
+
+	w.rtypeInfo(typInfo)
+	w.rtypeInfo(ifaceInfo)
+	if w.Bool(typInfo.derived || ifaceInfo.derived) {
+		w.Len(w.dict.itabIdx(typInfo, ifaceInfo))
+	}
+}
+
+// convRTTI writes information so that the reader can construct
+// expressions for converting from src to dst.
+func (w *writer) convRTTI(src, dst types2.Type) {
+	w.Sync(pkgbits.SyncConvRTTI)
+	w.itab(src, dst)
+}
+
+func (w *writer) exprType(iface types2.Type, typ syntax.Expr) {
+	base.Assertf(iface == nil || isInterface(iface), "%v must be nil or an interface type", iface)
+
+	tv := w.p.typeAndValue(typ)
+	assert(tv.IsType())
+
+	w.Sync(pkgbits.SyncExprType)
+	w.pos(typ)
+
+	if w.Bool(iface != nil && !iface.Underlying().(*types2.Interface).Empty()) {
+		w.itab(tv.Type, iface)
+	} else {
+		w.rtype(tv.Type)
+
+		info := w.p.typIdx(tv.Type, w.dict)
+		w.Bool(info.derived)
+	}
+}
+
+// isInterface reports whether typ is known to be an interface type.
+// If typ is a type parameter, then isInterface reports an internal
+// compiler error instead.
+func isInterface(typ types2.Type) bool {
+	if _, ok := typ.(*types2.TypeParam); ok {
+		// typ is a type parameter and may be instantiated as either a
+		// concrete or interface type, so the writer can't depend on
+		// knowing this.
+		base.Fatalf("%v is a type parameter", typ)
+	}
+
+	_, ok := typ.Underlying().(*types2.Interface)
+	return ok
+}
+
+// op writes an Op into the bitstream.
+func (w *writer) op(op ir.Op) {
+	// TODO(mdempsky): Remove in favor of explicit codes? Would make
+	// export data more stable against internal refactorings, but low
+	// priority at the moment.
+	assert(op != 0)
+	w.Sync(pkgbits.SyncOp)
+	w.Len(int(op))
+}
+
+// @@@ Package initialization
+
+// Caution: This code is still clumsy, because toolstash -cmp is
+// particularly sensitive to it.
+
+type typeDeclGen struct {
+	*syntax.TypeDecl
+	gen int
+
+	// Implicit type parameters in scope at this type declaration.
+	implicits []*types2.TypeName
+}
+
+type fileImports struct {
+	importedEmbed, importedUnsafe bool
+}
+
+// declCollector is a visitor type that collects compiler-needed
+// information about declarations that types2 doesn't track.
+//
+// Notably, it maps declared types and functions back to their
+// declaration statement, keeps track of implicit type parameters, and
+// assigns unique type "generation" numbers to local defined types.
+type declCollector struct {
+	pw         *pkgWriter
+	typegen    *int
+	file       *fileImports
+	withinFunc bool
+	implicits  []*types2.TypeName
+}
+
+func (c *declCollector) withTParams(obj types2.Object) *declCollector {
+	tparams := objTypeParams(obj)
+	n := tparams.Len()
+	if n == 0 {
+		return c
+	}
+
+	copy := *c
+	copy.implicits = copy.implicits[:len(copy.implicits):len(copy.implicits)]
+	for i := 0; i < n; i++ {
+		copy.implicits = append(copy.implicits, tparams.At(i).Obj())
+	}
+	return &copy
+}
+
+func (c *declCollector) Visit(n syntax.Node) syntax.Visitor {
+	pw := c.pw
+
+	switch n := n.(type) {
+	case *syntax.File:
+		pw.checkPragmas(n.Pragma, ir.GoBuildPragma, false)
+
+	case *syntax.ImportDecl:
+		pw.checkPragmas(n.Pragma, 0, false)
+
+		switch pkgNameOf(pw.info, n).Imported().Path() {
+		case "embed":
+			c.file.importedEmbed = true
+		case "unsafe":
+			c.file.importedUnsafe = true
+		}
+
+	case *syntax.ConstDecl:
+		pw.checkPragmas(n.Pragma, 0, false)
+
+	case *syntax.FuncDecl:
+		pw.checkPragmas(n.Pragma, funcPragmas, false)
+
+		obj := pw.info.Defs[n.Name].(*types2.Func)
+		pw.funDecls[obj] = n
+
+		return c.withTParams(obj)
+
+	case *syntax.TypeDecl:
+		obj := pw.info.Defs[n.Name].(*types2.TypeName)
+		d := typeDeclGen{TypeDecl: n, implicits: c.implicits}
+
+		if n.Alias {
+			pw.checkPragmas(n.Pragma, 0, false)
+		} else {
+			pw.checkPragmas(n.Pragma, 0, false)
+
+			// Assign a unique ID to function-scoped defined types.
+			if c.withinFunc {
+				*c.typegen++
+				d.gen = *c.typegen
+			}
+		}
+
+		pw.typDecls[obj] = d
+
+		// TODO(mdempsky): Omit? Not strictly necessary; only matters for
+		// type declarations within function literals within parameterized
+		// type declarations, but types2 the function literals will be
+		// constant folded away.
+		return c.withTParams(obj)
+
+	case *syntax.VarDecl:
+		pw.checkPragmas(n.Pragma, 0, true)
+
+		if p, ok := n.Pragma.(*pragmas); ok && len(p.Embeds) > 0 {
+			if err := checkEmbed(n, c.file.importedEmbed, c.withinFunc); err != nil {
+				pw.errorf(p.Embeds[0].Pos, "%s", err)
+			}
+		}
+
+	case *syntax.BlockStmt:
+		if !c.withinFunc {
+			copy := *c
+			copy.withinFunc = true
+			return &copy
+		}
+	}
+
+	return c
+}
+
+func (pw *pkgWriter) collectDecls(noders []*noder) {
+	var typegen int
+	for _, p := range noders {
+		var file fileImports
+
+		syntax.Walk(p.file, &declCollector{
+			pw:      pw,
+			typegen: &typegen,
+			file:    &file,
+		})
+
+		pw.cgoPragmas = append(pw.cgoPragmas, p.pragcgobuf...)
+
+		for _, l := range p.linknames {
+			if !file.importedUnsafe {
+				pw.errorf(l.pos, "//go:linkname only allowed in Go files that import \"unsafe\"")
+				continue
+			}
+
+			switch obj := pw.curpkg.Scope().Lookup(l.local).(type) {
+			case *types2.Func, *types2.Var:
+				if _, ok := pw.linknames[obj]; !ok {
+					pw.linknames[obj] = l.remote
+				} else {
+					pw.errorf(l.pos, "duplicate //go:linkname for %s", l.local)
+				}
+
+			default:
+				if types.AllowsGoVersion(1, 18) {
+					pw.errorf(l.pos, "//go:linkname must refer to declared function or variable")
+				}
+			}
+		}
+	}
+}
+
+func (pw *pkgWriter) checkPragmas(p syntax.Pragma, allowed ir.PragmaFlag, embedOK bool) {
+	if p == nil {
+		return
+	}
+	pragma := p.(*pragmas)
+
+	for _, pos := range pragma.Pos {
+		if pos.Flag&^allowed != 0 {
+			pw.errorf(pos.Pos, "misplaced compiler directive")
+		}
+	}
+
+	if !embedOK {
+		for _, e := range pragma.Embeds {
+			pw.errorf(e.Pos, "misplaced go:embed directive")
+		}
+	}
+}
+
+func (w *writer) pkgInit(noders []*noder) {
+	w.Len(len(w.p.cgoPragmas))
+	for _, cgoPragma := range w.p.cgoPragmas {
+		w.Strings(cgoPragma)
+	}
+
+	w.Sync(pkgbits.SyncDecls)
+	for _, p := range noders {
+		for _, decl := range p.file.DeclList {
+			w.pkgDecl(decl)
+		}
+	}
+	w.Code(declEnd)
+
+	w.Sync(pkgbits.SyncEOF)
+}
+
+func (w *writer) pkgDecl(decl syntax.Decl) {
+	switch decl := decl.(type) {
+	default:
+		w.p.unexpected("declaration", decl)
+
+	case *syntax.ImportDecl:
+
+	case *syntax.ConstDecl:
+		w.Code(declOther)
+		w.pkgObjs(decl.NameList...)
+
+	case *syntax.FuncDecl:
+		if decl.Name.Value == "_" {
+			break // skip blank functions
+		}
+
+		obj := w.p.info.Defs[decl.Name].(*types2.Func)
+		sig := obj.Type().(*types2.Signature)
+
+		if sig.RecvTypeParams() != nil || sig.TypeParams() != nil {
+			break // skip generic functions
+		}
+
+		if recv := sig.Recv(); recv != nil {
+			w.Code(declMethod)
+			w.typ(recvBase(recv))
+			w.selector(obj)
+			break
+		}
+
+		w.Code(declFunc)
+		w.pkgObjs(decl.Name)
+
+	case *syntax.TypeDecl:
+		if len(decl.TParamList) != 0 {
+			break // skip generic type decls
+		}
+
+		if decl.Name.Value == "_" {
+			break // skip blank type decls
+		}
+
+		name := w.p.info.Defs[decl.Name].(*types2.TypeName)
+		// Skip type declarations for interfaces that are only usable as
+		// type parameter bounds.
+		if iface, ok := name.Type().Underlying().(*types2.Interface); ok && !iface.IsMethodSet() {
+			break
+		}
+
+		w.Code(declOther)
+		w.pkgObjs(decl.Name)
+
+	case *syntax.VarDecl:
+		w.Code(declVar)
+		w.pos(decl)
+		w.pkgObjs(decl.NameList...)
+
+		// TODO(mdempsky): It would make sense to use multiExpr here, but
+		// that results in IR that confuses pkginit/initorder.go. So we
+		// continue using exprList, and let typecheck handle inserting any
+		// implicit conversions. That's okay though, because package-scope
+		// assignments never require dictionaries.
+		w.exprList(decl.Values)
+
+		var embeds []pragmaEmbed
+		if p, ok := decl.Pragma.(*pragmas); ok {
+			embeds = p.Embeds
+		}
+		w.Len(len(embeds))
+		for _, embed := range embeds {
+			w.pos(embed.Pos)
+			w.Strings(embed.Patterns)
+		}
+	}
+}
+
+func (w *writer) pkgObjs(names ...*syntax.Name) {
+	w.Sync(pkgbits.SyncDeclNames)
+	w.Len(len(names))
+
+	for _, name := range names {
+		obj, ok := w.p.info.Defs[name]
+		assert(ok)
+
+		w.Sync(pkgbits.SyncDeclName)
+		w.obj(obj, nil)
+	}
+}
+
+// @@@ Helpers
+
+// hasImplicitTypeParams reports whether obj is a defined type with
+// implicit type parameters (e.g., declared within a generic function
+// or method).
+func (p *pkgWriter) hasImplicitTypeParams(obj *types2.TypeName) bool {
+	if obj.Pkg() == p.curpkg {
+		decl, ok := p.typDecls[obj]
+		assert(ok)
+		if len(decl.implicits) != 0 {
+			return true
+		}
+	}
+	return false
+}
+
+// isDefinedType reports whether obj is a defined type.
+func isDefinedType(obj types2.Object) bool {
+	if obj, ok := obj.(*types2.TypeName); ok {
+		return !obj.IsAlias()
+	}
+	return false
+}
+
+// isGlobal reports whether obj was declared at package scope.
+//
+// Caveat: blank objects are not declared.
+func isGlobal(obj types2.Object) bool {
+	return obj.Parent() == obj.Pkg().Scope()
+}
+
+// lookupObj returns the object that expr refers to, if any. If expr
+// is an explicit instantiation of a generic object, then the instance
+// object is returned as well.
+func lookupObj(p *pkgWriter, expr syntax.Expr) (obj types2.Object, inst types2.Instance) {
+	if index, ok := expr.(*syntax.IndexExpr); ok {
+		args := unpackListExpr(index.Index)
+		if len(args) == 1 {
+			tv := p.typeAndValue(args[0])
+			if tv.IsValue() {
+				return // normal index expression
+			}
+		}
+
+		expr = index.X
+	}
+
+	// Strip package qualifier, if present.
+	if sel, ok := expr.(*syntax.SelectorExpr); ok {
+		if !isPkgQual(p.info, sel) {
+			return // normal selector expression
+		}
+		expr = sel.Sel
+	}
+
+	if name, ok := expr.(*syntax.Name); ok {
+		obj = p.info.Uses[name]
+		inst = p.info.Instances[name]
+	}
+	return
+}
+
+// isPkgQual reports whether the given selector expression is a
+// package-qualified identifier.
+func isPkgQual(info *types2.Info, sel *syntax.SelectorExpr) bool {
+	if name, ok := sel.X.(*syntax.Name); ok {
+		_, isPkgName := info.Uses[name].(*types2.PkgName)
+		return isPkgName
+	}
+	return false
+}
+
+// isNil reports whether expr is a (possibly parenthesized) reference
+// to the predeclared nil value.
+func isNil(p *pkgWriter, expr syntax.Expr) bool {
+	tv := p.typeAndValue(expr)
+	return tv.IsNil()
+}
+
+// recvBase returns the base type for the given receiver parameter.
+func recvBase(recv *types2.Var) *types2.Named {
+	typ := recv.Type()
+	if ptr, ok := typ.(*types2.Pointer); ok {
+		typ = ptr.Elem()
+	}
+	return typ.(*types2.Named)
+}
+
+// namesAsExpr returns a list of names as a syntax.Expr.
+func namesAsExpr(names []*syntax.Name) syntax.Expr {
+	if len(names) == 1 {
+		return names[0]
+	}
+
+	exprs := make([]syntax.Expr, len(names))
+	for i, name := range names {
+		exprs[i] = name
+	}
+	return &syntax.ListExpr{ElemList: exprs}
+}
+
+// fieldIndex returns the index of the struct field named by key.
+func fieldIndex(info *types2.Info, str *types2.Struct, key *syntax.Name) int {
+	field := info.Uses[key].(*types2.Var)
+
+	for i := 0; i < str.NumFields(); i++ {
+		if str.Field(i) == field {
+			return i
+		}
+	}
+
+	panic(fmt.Sprintf("%s: %v is not a field of %v", key.Pos(), field, str))
+}
+
+// objTypeParams returns the type parameters on the given object.
+func objTypeParams(obj types2.Object) *types2.TypeParamList {
+	switch obj := obj.(type) {
+	case *types2.Func:
+		sig := obj.Type().(*types2.Signature)
+		if sig.Recv() != nil {
+			return sig.RecvTypeParams()
+		}
+		return sig.TypeParams()
+	case *types2.TypeName:
+		if !obj.IsAlias() {
+			return obj.Type().(*types2.Named).TypeParams()
+		}
+	}
+	return nil
+}
+
+// splitNamed decomposes a use of a defined type into its original
+// type definition and the type arguments used to instantiate it.
+func splitNamed(typ *types2.Named) (*types2.TypeName, *types2.TypeList) {
+	base.Assertf(typ.TypeParams().Len() == typ.TypeArgs().Len(), "use of uninstantiated type: %v", typ)
+
+	orig := typ.Origin()
+	base.Assertf(orig.TypeArgs() == nil, "origin %v of %v has type arguments", orig, typ)
+	base.Assertf(typ.Obj() == orig.Obj(), "%v has object %v, but %v has object %v", typ, typ.Obj(), orig, orig.Obj())
+
+	return typ.Obj(), typ.TypeArgs()
+}
+
+func asPragmaFlag(p syntax.Pragma) ir.PragmaFlag {
+	if p == nil {
+		return 0
+	}
+	return p.(*pragmas).Flag
+}
+
+// isPtrTo reports whether from is the type *to.
+func isPtrTo(from, to types2.Type) bool {
+	ptr, ok := from.(*types2.Pointer)
+	return ok && types2.Identical(ptr.Elem(), to)
+}