Adding upstream version 1.21.8.upstream/1.21.8

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

1 files changed, 238 insertions, 0 deletions

diff --git a/src/cmd/compile/internal/pkginit/init.go b/src/cmd/compile/internal/pkginit/init.go
new file mode 100644
index 0000000..edb0d6a
--- /dev/null
+++ b/src/cmd/compile/internal/pkginit/init.go
@@ -0,0 +1,238 @@
+// 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 pkginit
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/noder"
+	"cmd/compile/internal/objw"
+	"cmd/compile/internal/staticinit"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+	"cmd/internal/obj"
+	"cmd/internal/objabi"
+	"cmd/internal/src"
+	"fmt"
+	"os"
+)
+
+// MakeInit creates a synthetic init function to handle any
+// package-scope initialization statements.
+//
+// TODO(mdempsky): Move into noder, so that the types2-based frontends
+// can use Info.InitOrder instead.
+func MakeInit() {
+	nf := initOrder(typecheck.Target.Decls)
+	if len(nf) == 0 {
+		return
+	}
+
+	// Make a function that contains all the initialization statements.
+	base.Pos = nf[0].Pos() // prolog/epilog gets line number of first init stmt
+	initializers := typecheck.Lookup("init")
+	fn := typecheck.DeclFunc(initializers, nil, nil, nil)
+	for _, dcl := range typecheck.InitTodoFunc.Dcl {
+		dcl.Curfn = fn
+	}
+	fn.Dcl = append(fn.Dcl, typecheck.InitTodoFunc.Dcl...)
+	typecheck.InitTodoFunc.Dcl = nil
+	fn.SetIsPackageInit(true)
+
+	// Outline (if legal/profitable) global map inits.
+	newfuncs := []*ir.Func{}
+	nf, newfuncs = staticinit.OutlineMapInits(nf)
+
+	// Suppress useless "can inline" diagnostics.
+	// Init functions are only called dynamically.
+	fn.SetInlinabilityChecked(true)
+	for _, nfn := range newfuncs {
+		nfn.SetInlinabilityChecked(true)
+	}
+
+	fn.Body = nf
+	typecheck.FinishFuncBody()
+
+	typecheck.Func(fn)
+	ir.WithFunc(fn, func() {
+		typecheck.Stmts(nf)
+	})
+	typecheck.Target.Decls = append(typecheck.Target.Decls, fn)
+	if base.Debug.WrapGlobalMapDbg > 1 {
+		fmt.Fprintf(os.Stderr, "=-= len(newfuncs) is %d for %v\n",
+			len(newfuncs), fn)
+	}
+	for _, nfn := range newfuncs {
+		if base.Debug.WrapGlobalMapDbg > 1 {
+			fmt.Fprintf(os.Stderr, "=-= add to target.decls %v\n", nfn)
+		}
+		typecheck.Target.Decls = append(typecheck.Target.Decls, ir.Node(nfn))
+	}
+
+	// Prepend to Inits, so it runs first, before any user-declared init
+	// functions.
+	typecheck.Target.Inits = append([]*ir.Func{fn}, typecheck.Target.Inits...)
+
+	if typecheck.InitTodoFunc.Dcl != nil {
+		// We only generate temps using InitTodoFunc if there
+		// are package-scope initialization statements, so
+		// something's weird if we get here.
+		base.Fatalf("InitTodoFunc still has declarations")
+	}
+	typecheck.InitTodoFunc = nil
+}
+
+// Task makes and returns an initialization record for the package.
+// See runtime/proc.go:initTask for its layout.
+// The 3 tasks for initialization are:
+//  1. Initialize all of the packages the current package depends on.
+//  2. Initialize all the variables that have initializers.
+//  3. Run any init functions.
+func Task() *ir.Name {
+	var deps []*obj.LSym // initTask records for packages the current package depends on
+	var fns []*obj.LSym  // functions to call for package initialization
+
+	// Find imported packages with init tasks.
+	for _, pkg := range typecheck.Target.Imports {
+		n, ok := pkg.Lookup(".inittask").Def.(*ir.Name)
+		if !ok {
+			continue
+		}
+		if n.Op() != ir.ONAME || n.Class != ir.PEXTERN {
+			base.Fatalf("bad inittask: %v", n)
+		}
+		deps = append(deps, n.Linksym())
+	}
+	if base.Flag.ASan {
+		// Make an initialization function to call runtime.asanregisterglobals to register an
+		// array of instrumented global variables when -asan is enabled. An instrumented global
+		// variable is described by a structure.
+		// See the _asan_global structure declared in src/runtime/asan/asan.go.
+		//
+		// func init {
+		// 		var globals []_asan_global {...}
+		// 		asanregisterglobals(&globals[0], len(globals))
+		// }
+		for _, n := range typecheck.Target.Externs {
+			if canInstrumentGlobal(n) {
+				name := n.Sym().Name
+				InstrumentGlobalsMap[name] = n
+				InstrumentGlobalsSlice = append(InstrumentGlobalsSlice, n)
+			}
+		}
+		ni := len(InstrumentGlobalsMap)
+		if ni != 0 {
+			// Make an init._ function.
+			base.Pos = base.AutogeneratedPos
+			typecheck.DeclContext = ir.PEXTERN
+			name := noder.Renameinit()
+			fnInit := typecheck.DeclFunc(name, nil, nil, nil)
+
+			// Get an array of instrumented global variables.
+			globals := instrumentGlobals(fnInit)
+
+			// Call runtime.asanregisterglobals function to poison redzones.
+			// runtime.asanregisterglobals(unsafe.Pointer(&globals[0]), ni)
+			asanf := typecheck.NewName(ir.Pkgs.Runtime.Lookup("asanregisterglobals"))
+			ir.MarkFunc(asanf)
+			asanf.SetType(types.NewSignature(nil, []*types.Field{
+				types.NewField(base.Pos, nil, types.Types[types.TUNSAFEPTR]),
+				types.NewField(base.Pos, nil, types.Types[types.TUINTPTR]),
+			}, nil))
+			asancall := ir.NewCallExpr(base.Pos, ir.OCALL, asanf, nil)
+			asancall.Args.Append(typecheck.ConvNop(typecheck.NodAddr(
+				ir.NewIndexExpr(base.Pos, globals, ir.NewInt(base.Pos, 0))), types.Types[types.TUNSAFEPTR]))
+			asancall.Args.Append(typecheck.DefaultLit(ir.NewInt(base.Pos, int64(ni)), types.Types[types.TUINTPTR]))
+
+			fnInit.Body.Append(asancall)
+			typecheck.FinishFuncBody()
+			typecheck.Func(fnInit)
+			ir.CurFunc = fnInit
+			typecheck.Stmts(fnInit.Body)
+			ir.CurFunc = nil
+
+			typecheck.Target.Decls = append(typecheck.Target.Decls, fnInit)
+			typecheck.Target.Inits = append(typecheck.Target.Inits, fnInit)
+		}
+	}
+
+	// Record user init functions.
+	for _, fn := range typecheck.Target.Inits {
+		if fn.Sym().Name == "init" {
+			// Synthetic init function for initialization of package-scope
+			// variables. We can use staticinit to optimize away static
+			// assignments.
+			s := staticinit.Schedule{
+				Plans: make(map[ir.Node]*staticinit.Plan),
+				Temps: make(map[ir.Node]*ir.Name),
+			}
+			for _, n := range fn.Body {
+				s.StaticInit(n)
+			}
+			fn.Body = s.Out
+			ir.WithFunc(fn, func() {
+				typecheck.Stmts(fn.Body)
+			})
+
+			if len(fn.Body) == 0 {
+				fn.Body = []ir.Node{ir.NewBlockStmt(src.NoXPos, nil)}
+			}
+		}
+
+		// Skip init functions with empty bodies.
+		if len(fn.Body) == 1 {
+			if stmt := fn.Body[0]; stmt.Op() == ir.OBLOCK && len(stmt.(*ir.BlockStmt).List) == 0 {
+				continue
+			}
+		}
+		fns = append(fns, fn.Nname.Linksym())
+	}
+
+	if len(deps) == 0 && len(fns) == 0 && types.LocalPkg.Path != "main" && types.LocalPkg.Path != "runtime" {
+		return nil // nothing to initialize
+	}
+
+	// Make an .inittask structure.
+	sym := typecheck.Lookup(".inittask")
+	task := typecheck.NewName(sym)
+	task.SetType(types.Types[types.TUINT8]) // fake type
+	task.Class = ir.PEXTERN
+	sym.Def = task
+	lsym := task.Linksym()
+	ot := 0
+	ot = objw.Uint32(lsym, ot, 0) // state: not initialized yet
+	ot = objw.Uint32(lsym, ot, uint32(len(fns)))
+	for _, f := range fns {
+		ot = objw.SymPtr(lsym, ot, f, 0)
+	}
+
+	// Add relocations which tell the linker all of the packages
+	// that this package depends on (and thus, all of the packages
+	// that need to be initialized before this one).
+	for _, d := range deps {
+		r := obj.Addrel(lsym)
+		r.Type = objabi.R_INITORDER
+		r.Sym = d
+	}
+	// An initTask has pointers, but none into the Go heap.
+	// It's not quite read only, the state field must be modifiable.
+	objw.Global(lsym, int32(ot), obj.NOPTR)
+	return task
+}
+
+// initRequiredForCoverage returns TRUE if we need to force creation
+// of an init function for the package so as to insert a coverage
+// runtime registration call.
+func initRequiredForCoverage(l []ir.Node) bool {
+	if base.Flag.Cfg.CoverageInfo == nil {
+		return false
+	}
+	for _, n := range l {
+		if n.Op() == ir.ODCLFUNC {
+			return true
+		}
+	}
+	return false
+}