diff options
Diffstat (limited to 'src/cmd/compile/internal/ssagen')
| -rw-r--r-- | src/cmd/compile/internal/ssagen/abi.go | 451 | ||||
| -rw-r--r-- | src/cmd/compile/internal/ssagen/arch.go | 51 | ||||
| -rw-r--r-- | src/cmd/compile/internal/ssagen/nowb.go | 206 | ||||
| -rw-r--r-- | src/cmd/compile/internal/ssagen/pgen.go | 335 | ||||
| -rw-r--r-- | src/cmd/compile/internal/ssagen/phi.go | 557 | ||||
| -rw-r--r-- | src/cmd/compile/internal/ssagen/ssa.go | 8150 |
6 files changed, 9750 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/ssagen/abi.go b/src/cmd/compile/internal/ssagen/abi.go new file mode 100644 index 0000000..c97d60b --- /dev/null +++ b/src/cmd/compile/internal/ssagen/abi.go @@ -0,0 +1,451 @@ +// 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 ssagen + +import ( + "fmt" + "internal/buildcfg" + "log" + "os" + "strings" + + "cmd/compile/internal/abi" + "cmd/compile/internal/base" + "cmd/compile/internal/ir" + "cmd/compile/internal/objw" + "cmd/compile/internal/typecheck" + "cmd/compile/internal/types" + "cmd/internal/obj" + "cmd/internal/obj/wasm" +) + +// SymABIs records information provided by the assembler about symbol +// definition ABIs and reference ABIs. +type SymABIs struct { + defs map[string]obj.ABI + refs map[string]obj.ABISet +} + +func NewSymABIs() *SymABIs { + return &SymABIs{ + defs: make(map[string]obj.ABI), + refs: make(map[string]obj.ABISet), + } +} + +// canonicalize returns the canonical name used for a linker symbol in +// s's maps. Symbols in this package may be written either as "".X or +// with the package's import path already in the symbol. This rewrites +// both to use the full path, which matches compiler-generated linker +// symbol names. +func (s *SymABIs) canonicalize(linksym string) string { + // If the symbol is already prefixed with "", rewrite it to start + // with LocalPkg.Prefix. + // + // TODO(mdempsky): Have cmd/asm stop writing out symbols like this. + if strings.HasPrefix(linksym, `"".`) { + return types.LocalPkg.Prefix + linksym[2:] + } + return linksym +} + +// ReadSymABIs reads a symabis file that specifies definitions and +// references of text symbols by ABI. +// +// The symabis format is a set of lines, where each line is a sequence +// of whitespace-separated fields. The first field is a verb and is +// either "def" for defining a symbol ABI or "ref" for referencing a +// symbol using an ABI. For both "def" and "ref", the second field is +// the symbol name and the third field is the ABI name, as one of the +// named cmd/internal/obj.ABI constants. +func (s *SymABIs) ReadSymABIs(file string) { + data, err := os.ReadFile(file) + if err != nil { + log.Fatalf("-symabis: %v", err) + } + + for lineNum, line := range strings.Split(string(data), "\n") { + lineNum++ // 1-based + line = strings.TrimSpace(line) + if line == "" || strings.HasPrefix(line, "#") { + continue + } + + parts := strings.Fields(line) + switch parts[0] { + case "def", "ref": + // Parse line. + if len(parts) != 3 { + log.Fatalf(`%s:%d: invalid symabi: syntax is "%s sym abi"`, file, lineNum, parts[0]) + } + sym, abistr := parts[1], parts[2] + abi, valid := obj.ParseABI(abistr) + if !valid { + log.Fatalf(`%s:%d: invalid symabi: unknown abi "%s"`, file, lineNum, abistr) + } + + sym = s.canonicalize(sym) + + // Record for later. + if parts[0] == "def" { + s.defs[sym] = abi + } else { + s.refs[sym] |= obj.ABISetOf(abi) + } + default: + log.Fatalf(`%s:%d: invalid symabi type "%s"`, file, lineNum, parts[0]) + } + } +} + +// GenABIWrappers applies ABI information to Funcs and generates ABI +// wrapper functions where necessary. +func (s *SymABIs) GenABIWrappers() { + // For cgo exported symbols, we tell the linker to export the + // definition ABI to C. That also means that we don't want to + // create ABI wrappers even if there's a linkname. + // + // TODO(austin): Maybe we want to create the ABI wrappers, but + // ensure the linker exports the right ABI definition under + // the unmangled name? + cgoExports := make(map[string][]*[]string) + for i, prag := range typecheck.Target.CgoPragmas { + switch prag[0] { + case "cgo_export_static", "cgo_export_dynamic": + symName := s.canonicalize(prag[1]) + pprag := &typecheck.Target.CgoPragmas[i] + cgoExports[symName] = append(cgoExports[symName], pprag) + } + } + + // Apply ABI defs and refs to Funcs and generate wrappers. + // + // This may generate new decls for the wrappers, but we + // specifically *don't* want to visit those, lest we create + // wrappers for wrappers. + for _, fn := range typecheck.Target.Decls { + if fn.Op() != ir.ODCLFUNC { + continue + } + fn := fn.(*ir.Func) + nam := fn.Nname + if ir.IsBlank(nam) { + continue + } + sym := nam.Sym() + + symName := sym.Linkname + if symName == "" { + symName = sym.Pkg.Prefix + "." + sym.Name + } + symName = s.canonicalize(symName) + + // Apply definitions. + defABI, hasDefABI := s.defs[symName] + if hasDefABI { + if len(fn.Body) != 0 { + base.ErrorfAt(fn.Pos(), 0, "%v defined in both Go and assembly", fn) + } + fn.ABI = defABI + } + + if fn.Pragma&ir.CgoUnsafeArgs != 0 { + // CgoUnsafeArgs indicates the function (or its callee) uses + // offsets to dispatch arguments, which currently using ABI0 + // frame layout. Pin it to ABI0. + fn.ABI = obj.ABI0 + } + + // If cgo-exported, add the definition ABI to the cgo + // pragmas. + cgoExport := cgoExports[symName] + for _, pprag := range cgoExport { + // The export pragmas have the form: + // + // cgo_export_* <local> [<remote>] + // + // If <remote> is omitted, it's the same as + // <local>. + // + // Expand to + // + // cgo_export_* <local> <remote> <ABI> + if len(*pprag) == 2 { + *pprag = append(*pprag, (*pprag)[1]) + } + // Add the ABI argument. + *pprag = append(*pprag, fn.ABI.String()) + } + + // Apply references. + if abis, ok := s.refs[symName]; ok { + fn.ABIRefs |= abis + } + // Assume all functions are referenced at least as + // ABIInternal, since they may be referenced from + // other packages. + fn.ABIRefs.Set(obj.ABIInternal, true) + + // If a symbol is defined in this package (either in + // Go or assembly) and given a linkname, it may be + // referenced from another package, so make it + // callable via any ABI. It's important that we know + // it's defined in this package since other packages + // may "pull" symbols using linkname and we don't want + // to create duplicate ABI wrappers. + // + // However, if it's given a linkname for exporting to + // C, then we don't make ABI wrappers because the cgo + // tool wants the original definition. + hasBody := len(fn.Body) != 0 + if sym.Linkname != "" && (hasBody || hasDefABI) && len(cgoExport) == 0 { + fn.ABIRefs |= obj.ABISetCallable + } + + // Double check that cgo-exported symbols don't get + // any wrappers. + if len(cgoExport) > 0 && fn.ABIRefs&^obj.ABISetOf(fn.ABI) != 0 { + base.Fatalf("cgo exported function %v cannot have ABI wrappers", fn) + } + + if !buildcfg.Experiment.RegabiWrappers { + continue + } + + forEachWrapperABI(fn, makeABIWrapper) + } +} + +func forEachWrapperABI(fn *ir.Func, cb func(fn *ir.Func, wrapperABI obj.ABI)) { + need := fn.ABIRefs &^ obj.ABISetOf(fn.ABI) + if need == 0 { + return + } + + for wrapperABI := obj.ABI(0); wrapperABI < obj.ABICount; wrapperABI++ { + if !need.Get(wrapperABI) { + continue + } + cb(fn, wrapperABI) + } +} + +// makeABIWrapper creates a new function that will be called with +// wrapperABI and calls "f" using f.ABI. +func makeABIWrapper(f *ir.Func, wrapperABI obj.ABI) { + if base.Debug.ABIWrap != 0 { + fmt.Fprintf(os.Stderr, "=-= %v to %v wrapper for %v\n", wrapperABI, f.ABI, f) + } + + // Q: is this needed? + savepos := base.Pos + savedclcontext := typecheck.DeclContext + savedcurfn := ir.CurFunc + + base.Pos = base.AutogeneratedPos + typecheck.DeclContext = ir.PEXTERN + + // At the moment we don't support wrapping a method, we'd need machinery + // below to handle the receiver. Panic if we see this scenario. + ft := f.Nname.Type() + if ft.NumRecvs() != 0 { + base.ErrorfAt(f.Pos(), 0, "makeABIWrapper support for wrapping methods not implemented") + return + } + + // Reuse f's types.Sym to create a new ODCLFUNC/function. + fn := typecheck.DeclFunc(f.Nname.Sym(), nil, + typecheck.NewFuncParams(ft.Params(), true), + typecheck.NewFuncParams(ft.Results(), false)) + fn.ABI = wrapperABI + + fn.SetABIWrapper(true) + fn.SetDupok(true) + + // ABI0-to-ABIInternal wrappers will be mainly loading params from + // stack into registers (and/or storing stack locations back to + // registers after the wrapped call); in most cases they won't + // need to allocate stack space, so it should be OK to mark them + // as NOSPLIT in these cases. In addition, my assumption is that + // functions written in assembly are NOSPLIT in most (but not all) + // cases. In the case of an ABIInternal target that has too many + // parameters to fit into registers, the wrapper would need to + // allocate stack space, but this seems like an unlikely scenario. + // Hence: mark these wrappers NOSPLIT. + // + // ABIInternal-to-ABI0 wrappers on the other hand will be taking + // things in registers and pushing them onto the stack prior to + // the ABI0 call, meaning that they will always need to allocate + // stack space. If the compiler marks them as NOSPLIT this seems + // as though it could lead to situations where the linker's + // nosplit-overflow analysis would trigger a link failure. On the + // other hand if they not tagged NOSPLIT then this could cause + // problems when building the runtime (since there may be calls to + // asm routine in cases where it's not safe to grow the stack). In + // most cases the wrapper would be (in effect) inlined, but are + // there (perhaps) indirect calls from the runtime that could run + // into trouble here. + // FIXME: at the moment all.bash does not pass when I leave out + // NOSPLIT for these wrappers, so all are currently tagged with NOSPLIT. + fn.Pragma |= ir.Nosplit + + // Generate call. Use tail call if no params and no returns, + // but a regular call otherwise. + // + // Note: ideally we would be using a tail call in cases where + // there are params but no returns for ABI0->ABIInternal wrappers, + // provided that all params fit into registers (e.g. we don't have + // to allocate any stack space). Doing this will require some + // extra work in typecheck/walk/ssa, might want to add a new node + // OTAILCALL or something to this effect. + tailcall := fn.Type().NumResults() == 0 && fn.Type().NumParams() == 0 && fn.Type().NumRecvs() == 0 + if base.Ctxt.Arch.Name == "ppc64le" && base.Ctxt.Flag_dynlink { + // cannot tailcall on PPC64 with dynamic linking, as we need + // to restore R2 after call. + tailcall = false + } + if base.Ctxt.Arch.Name == "amd64" && wrapperABI == obj.ABIInternal { + // cannot tailcall from ABIInternal to ABI0 on AMD64, as we need + // to special registers (X15) when returning to ABIInternal. + tailcall = false + } + + var tail ir.Node + call := ir.NewCallExpr(base.Pos, ir.OCALL, f.Nname, nil) + call.Args = ir.ParamNames(fn.Type()) + call.IsDDD = fn.Type().IsVariadic() + tail = call + if tailcall { + tail = ir.NewTailCallStmt(base.Pos, call) + } else if fn.Type().NumResults() > 0 { + n := ir.NewReturnStmt(base.Pos, nil) + n.Results = []ir.Node{call} + tail = n + } + fn.Body.Append(tail) + + typecheck.FinishFuncBody() + + typecheck.Func(fn) + ir.CurFunc = fn + typecheck.Stmts(fn.Body) + + typecheck.Target.Decls = append(typecheck.Target.Decls, fn) + + // Restore previous context. + base.Pos = savepos + typecheck.DeclContext = savedclcontext + ir.CurFunc = savedcurfn +} + +// CreateWasmImportWrapper creates a wrapper for imported WASM functions to +// adapt them to the Go calling convention. The body for this function is +// generated in cmd/internal/obj/wasm/wasmobj.go +func CreateWasmImportWrapper(fn *ir.Func) bool { + if fn.WasmImport == nil { + return false + } + if buildcfg.GOARCH != "wasm" { + base.FatalfAt(fn.Pos(), "CreateWasmImportWrapper call not supported on %s: func was %v", buildcfg.GOARCH, fn) + } + + ir.InitLSym(fn, true) + + setupWasmABI(fn) + + pp := objw.NewProgs(fn, 0) + defer pp.Free() + pp.Text.To.Type = obj.TYPE_TEXTSIZE + pp.Text.To.Val = int32(types.RoundUp(fn.Type().ArgWidth(), int64(types.RegSize))) + // Wrapper functions never need their own stack frame + pp.Text.To.Offset = 0 + pp.Flush() + + return true +} + +func paramsToWasmFields(f *ir.Func, result *abi.ABIParamResultInfo, abiParams []abi.ABIParamAssignment) []obj.WasmField { + wfs := make([]obj.WasmField, len(abiParams)) + for i, p := range abiParams { + t := p.Type + switch t.Kind() { + case types.TINT32, types.TUINT32: + wfs[i].Type = obj.WasmI32 + case types.TINT64, types.TUINT64: + wfs[i].Type = obj.WasmI64 + case types.TFLOAT32: + wfs[i].Type = obj.WasmF32 + case types.TFLOAT64: + wfs[i].Type = obj.WasmF64 + case types.TUNSAFEPTR: + wfs[i].Type = obj.WasmPtr + default: + base.ErrorfAt(f.Pos(), 0, "go:wasmimport %s %s: unsupported parameter type %s", f.WasmImport.Module, f.WasmImport.Name, t.String()) + } + wfs[i].Offset = p.FrameOffset(result) + } + return wfs +} + +func resultsToWasmFields(f *ir.Func, result *abi.ABIParamResultInfo, abiParams []abi.ABIParamAssignment) []obj.WasmField { + if len(abiParams) > 1 { + base.ErrorfAt(f.Pos(), 0, "go:wasmimport %s %s: too many return values", f.WasmImport.Module, f.WasmImport.Name) + return nil + } + wfs := make([]obj.WasmField, len(abiParams)) + for i, p := range abiParams { + t := p.Type + switch t.Kind() { + case types.TINT32, types.TUINT32: + wfs[i].Type = obj.WasmI32 + case types.TINT64, types.TUINT64: + wfs[i].Type = obj.WasmI64 + case types.TFLOAT32: + wfs[i].Type = obj.WasmF32 + case types.TFLOAT64: + wfs[i].Type = obj.WasmF64 + default: + base.ErrorfAt(f.Pos(), 0, "go:wasmimport %s %s: unsupported result type %s", f.WasmImport.Module, f.WasmImport.Name, t.String()) + } + wfs[i].Offset = p.FrameOffset(result) + } + return wfs +} + +// setupTextLSym initializes the LSym for a with-body text symbol. +func setupWasmABI(f *ir.Func) { + wi := obj.WasmImport{ + Module: f.WasmImport.Module, + Name: f.WasmImport.Name, + } + if wi.Module == wasm.GojsModule { + // Functions that are imported from the "gojs" module use a special + // ABI that just accepts the stack pointer. + // Example: + // + // //go:wasmimport gojs add + // func importedAdd(a, b uint) uint + // + // will roughly become + // + // (import "gojs" "add" (func (param i32))) + wi.Params = []obj.WasmField{{Type: obj.WasmI32}} + } else { + // All other imported functions use the normal WASM ABI. + // Example: + // + // //go:wasmimport a_module add + // func importedAdd(a, b uint) uint + // + // will roughly become + // + // (import "a_module" "add" (func (param i32 i32) (result i32))) + abiConfig := AbiForBodylessFuncStackMap(f) + abiInfo := abiConfig.ABIAnalyzeFuncType(f.Type().FuncType()) + wi.Params = paramsToWasmFields(f, abiInfo, abiInfo.InParams()) + wi.Results = resultsToWasmFields(f, abiInfo, abiInfo.OutParams()) + } + f.LSym.Func().WasmImport = &wi +} diff --git a/src/cmd/compile/internal/ssagen/arch.go b/src/cmd/compile/internal/ssagen/arch.go new file mode 100644 index 0000000..483e45c --- /dev/null +++ b/src/cmd/compile/internal/ssagen/arch.go @@ -0,0 +1,51 @@ +// 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 ssagen + +import ( + "cmd/compile/internal/ir" + "cmd/compile/internal/objw" + "cmd/compile/internal/ssa" + "cmd/compile/internal/types" + "cmd/internal/obj" +) + +var Arch ArchInfo + +// interface to back end + +type ArchInfo struct { + LinkArch *obj.LinkArch + + REGSP int + MAXWIDTH int64 + SoftFloat bool + + PadFrame func(int64) int64 + + // ZeroRange zeroes a range of memory on stack. It is only inserted + // at function entry, and it is ok to clobber registers. + ZeroRange func(*objw.Progs, *obj.Prog, int64, int64, *uint32) *obj.Prog + + Ginsnop func(*objw.Progs) *obj.Prog + + // SSAMarkMoves marks any MOVXconst ops that need to avoid clobbering flags. + SSAMarkMoves func(*State, *ssa.Block) + + // SSAGenValue emits Prog(s) for the Value. + SSAGenValue func(*State, *ssa.Value) + + // SSAGenBlock emits end-of-block Progs. SSAGenValue should be called + // for all values in the block before SSAGenBlock. + SSAGenBlock func(s *State, b, next *ssa.Block) + + // LoadRegResult emits instructions that loads register-assigned result + // at n+off (n is PPARAMOUT) to register reg. The result is already in + // memory. Used in open-coded defer return path. + LoadRegResult func(s *State, f *ssa.Func, t *types.Type, reg int16, n *ir.Name, off int64) *obj.Prog + + // SpillArgReg emits instructions that spill reg to n+off. + SpillArgReg func(pp *objw.Progs, p *obj.Prog, f *ssa.Func, t *types.Type, reg int16, n *ir.Name, off int64) *obj.Prog +} diff --git a/src/cmd/compile/internal/ssagen/nowb.go b/src/cmd/compile/internal/ssagen/nowb.go new file mode 100644 index 0000000..9de1b9a --- /dev/null +++ b/src/cmd/compile/internal/ssagen/nowb.go @@ -0,0 +1,206 @@ +// 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 ssagen + +import ( + "fmt" + "strings" + + "cmd/compile/internal/base" + "cmd/compile/internal/ir" + "cmd/compile/internal/typecheck" + "cmd/compile/internal/types" + "cmd/internal/obj" + "cmd/internal/src" +) + +func EnableNoWriteBarrierRecCheck() { + nowritebarrierrecCheck = newNowritebarrierrecChecker() +} + +func NoWriteBarrierRecCheck() { + // Write barriers are now known. Check the + // call graph. + nowritebarrierrecCheck.check() + nowritebarrierrecCheck = nil +} + +var nowritebarrierrecCheck *nowritebarrierrecChecker + +type nowritebarrierrecChecker struct { + // extraCalls contains extra function calls that may not be + // visible during later analysis. It maps from the ODCLFUNC of + // the caller to a list of callees. + extraCalls map[*ir.Func][]nowritebarrierrecCall + + // curfn is the current function during AST walks. + curfn *ir.Func +} + +type nowritebarrierrecCall struct { + target *ir.Func // caller or callee + lineno src.XPos // line of call +} + +// newNowritebarrierrecChecker creates a nowritebarrierrecChecker. It +// must be called before walk. +func newNowritebarrierrecChecker() *nowritebarrierrecChecker { + c := &nowritebarrierrecChecker{ + extraCalls: make(map[*ir.Func][]nowritebarrierrecCall), + } + + // Find all systemstack calls and record their targets. In + // general, flow analysis can't see into systemstack, but it's + // important to handle it for this check, so we model it + // directly. This has to happen before transforming closures in walk since + // it's a lot harder to work out the argument after. + for _, n := range typecheck.Target.Decls { + if n.Op() != ir.ODCLFUNC { + continue + } + c.curfn = n.(*ir.Func) + if c.curfn.ABIWrapper() { + // We only want "real" calls to these + // functions, not the generated ones within + // their own ABI wrappers. + continue + } + ir.Visit(n, c.findExtraCalls) + } + c.curfn = nil + return c +} + +func (c *nowritebarrierrecChecker) findExtraCalls(nn ir.Node) { + if nn.Op() != ir.OCALLFUNC { + return + } + n := nn.(*ir.CallExpr) + if n.X == nil || n.X.Op() != ir.ONAME { + return + } + fn := n.X.(*ir.Name) + if fn.Class != ir.PFUNC || fn.Defn == nil { + return + } + if !types.IsRuntimePkg(fn.Sym().Pkg) || fn.Sym().Name != "systemstack" { + return + } + + var callee *ir.Func + arg := n.Args[0] + switch arg.Op() { + case ir.ONAME: + arg := arg.(*ir.Name) + callee = arg.Defn.(*ir.Func) + case ir.OCLOSURE: + arg := arg.(*ir.ClosureExpr) + callee = arg.Func + default: + base.Fatalf("expected ONAME or OCLOSURE node, got %+v", arg) + } + if callee.Op() != ir.ODCLFUNC { + base.Fatalf("expected ODCLFUNC node, got %+v", callee) + } + c.extraCalls[c.curfn] = append(c.extraCalls[c.curfn], nowritebarrierrecCall{callee, n.Pos()}) +} + +// recordCall records a call from ODCLFUNC node "from", to function +// symbol "to" at position pos. +// +// This should be done as late as possible during compilation to +// capture precise call graphs. The target of the call is an LSym +// because that's all we know after we start SSA. +// +// This can be called concurrently for different from Nodes. +func (c *nowritebarrierrecChecker) recordCall(fn *ir.Func, to *obj.LSym, pos src.XPos) { + // We record this information on the *Func so this is concurrent-safe. + if fn.NWBRCalls == nil { + fn.NWBRCalls = new([]ir.SymAndPos) + } + *fn.NWBRCalls = append(*fn.NWBRCalls, ir.SymAndPos{Sym: to, Pos: pos}) +} + +func (c *nowritebarrierrecChecker) check() { + // We walk the call graph as late as possible so we can + // capture all calls created by lowering, but this means we + // only get to see the obj.LSyms of calls. symToFunc lets us + // get back to the ODCLFUNCs. + symToFunc := make(map[*obj.LSym]*ir.Func) + // funcs records the back-edges of the BFS call graph walk. It + // maps from the ODCLFUNC of each function that must not have + // write barriers to the call that inhibits them. Functions + // that are directly marked go:nowritebarrierrec are in this + // map with a zero-valued nowritebarrierrecCall. This also + // acts as the set of marks for the BFS of the call graph. + funcs := make(map[*ir.Func]nowritebarrierrecCall) + // q is the queue of ODCLFUNC Nodes to visit in BFS order. + var q ir.NameQueue + + for _, n := range typecheck.Target.Decls { + if n.Op() != ir.ODCLFUNC { + continue + } + fn := n.(*ir.Func) + + symToFunc[fn.LSym] = fn + + // Make nowritebarrierrec functions BFS roots. + if fn.Pragma&ir.Nowritebarrierrec != 0 { + funcs[fn] = nowritebarrierrecCall{} + q.PushRight(fn.Nname) + } + // Check go:nowritebarrier functions. + if fn.Pragma&ir.Nowritebarrier != 0 && fn.WBPos.IsKnown() { + base.ErrorfAt(fn.WBPos, 0, "write barrier prohibited") + } + } + + // Perform a BFS of the call graph from all + // go:nowritebarrierrec functions. + enqueue := func(src, target *ir.Func, pos src.XPos) { + if target.Pragma&ir.Yeswritebarrierrec != 0 { + // Don't flow into this function. + return + } + if _, ok := funcs[target]; ok { + // Already found a path to target. + return + } + + // Record the path. + funcs[target] = nowritebarrierrecCall{target: src, lineno: pos} + q.PushRight(target.Nname) + } + for !q.Empty() { + fn := q.PopLeft().Func + + // Check fn. + if fn.WBPos.IsKnown() { + var err strings.Builder + call := funcs[fn] + for call.target != nil { + fmt.Fprintf(&err, "\n\t%v: called by %v", base.FmtPos(call.lineno), call.target.Nname) + call = funcs[call.target] + } + base.ErrorfAt(fn.WBPos, 0, "write barrier prohibited by caller; %v%s", fn.Nname, err.String()) + continue + } + + // Enqueue fn's calls. + for _, callee := range c.extraCalls[fn] { + enqueue(fn, callee.target, callee.lineno) + } + if fn.NWBRCalls == nil { + continue + } + for _, callee := range *fn.NWBRCalls { + target := symToFunc[callee.Sym] + if target != nil { + enqueue(fn, target, callee.Pos) + } + } + } +} diff --git a/src/cmd/compile/internal/ssagen/pgen.go b/src/cmd/compile/internal/ssagen/pgen.go new file mode 100644 index 0000000..9fd3f2a --- /dev/null +++ b/src/cmd/compile/internal/ssagen/pgen.go @@ -0,0 +1,335 @@ +// Copyright 2011 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 ssagen + +import ( + "fmt" + "internal/buildcfg" + "os" + "sort" + "sync" + + "cmd/compile/internal/base" + "cmd/compile/internal/ir" + "cmd/compile/internal/objw" + "cmd/compile/internal/ssa" + "cmd/compile/internal/types" + "cmd/internal/obj" + "cmd/internal/objabi" + "cmd/internal/src" +) + +// cmpstackvarlt reports whether the stack variable a sorts before b. +// +// Sort the list of stack variables. Autos after anything else, +// within autos, unused after used, within used, things with +// pointers first, zeroed things first, and then decreasing size. +// Because autos are laid out in decreasing addresses +// on the stack, pointers first, zeroed things first and decreasing size +// really means, in memory, things with pointers needing zeroing at +// the top of the stack and increasing in size. +// Non-autos sort on offset. +func cmpstackvarlt(a, b *ir.Name) bool { + if needAlloc(a) != needAlloc(b) { + return needAlloc(b) + } + + if !needAlloc(a) { + return a.FrameOffset() < b.FrameOffset() + } + + if a.Used() != b.Used() { + return a.Used() + } + + ap := a.Type().HasPointers() + bp := b.Type().HasPointers() + if ap != bp { + return ap + } + + ap = a.Needzero() + bp = b.Needzero() + if ap != bp { + return ap + } + + if a.Type().Size() != b.Type().Size() { + return a.Type().Size() > b.Type().Size() + } + + return a.Sym().Name < b.Sym().Name +} + +// byStackVar implements sort.Interface for []*Node using cmpstackvarlt. +type byStackVar []*ir.Name + +func (s byStackVar) Len() int { return len(s) } +func (s byStackVar) Less(i, j int) bool { return cmpstackvarlt(s[i], s[j]) } +func (s byStackVar) Swap(i, j int) { s[i], s[j] = s[j], s[i] } + +// needAlloc reports whether n is within the current frame, for which we need to +// allocate space. In particular, it excludes arguments and results, which are in +// the callers frame. +func needAlloc(n *ir.Name) bool { + if n.Op() != ir.ONAME { + base.FatalfAt(n.Pos(), "%v has unexpected Op %v", n, n.Op()) + } + + switch n.Class { + case ir.PAUTO: + return true + case ir.PPARAM: + return false + case ir.PPARAMOUT: + return n.IsOutputParamInRegisters() + + default: + base.FatalfAt(n.Pos(), "%v has unexpected Class %v", n, n.Class) + return false + } +} + +func (s *ssafn) AllocFrame(f *ssa.Func) { + s.stksize = 0 + s.stkptrsize = 0 + s.stkalign = int64(types.RegSize) + fn := s.curfn + + // Mark the PAUTO's unused. + for _, ln := range fn.Dcl { + if needAlloc(ln) { + ln.SetUsed(false) + } + } + + for _, l := range f.RegAlloc { + if ls, ok := l.(ssa.LocalSlot); ok { + ls.N.SetUsed(true) + } + } + + for _, b := range f.Blocks { + for _, v := range b.Values { + if n, ok := v.Aux.(*ir.Name); ok { + switch n.Class { + case ir.PPARAMOUT: + if n.IsOutputParamInRegisters() && v.Op == ssa.OpVarDef { + // ignore VarDef, look for "real" uses. + // TODO: maybe do this for PAUTO as well? + continue + } + fallthrough + case ir.PPARAM, ir.PAUTO: + n.SetUsed(true) + } + } + } + } + + // Use sort.Stable instead of sort.Sort so stack layout (and thus + // compiler output) is less sensitive to frontend changes that + // introduce or remove unused variables. + sort.Stable(byStackVar(fn.Dcl)) + + // Reassign stack offsets of the locals that are used. + lastHasPtr := false + for i, n := range fn.Dcl { + if n.Op() != ir.ONAME || n.Class != ir.PAUTO && !(n.Class == ir.PPARAMOUT && n.IsOutputParamInRegisters()) { + // i.e., stack assign if AUTO, or if PARAMOUT in registers (which has no predefined spill locations) + continue + } + if !n.Used() { + fn.DebugInfo.(*ssa.FuncDebug).OptDcl = fn.Dcl[i:] + fn.Dcl = fn.Dcl[:i] + break + } + + types.CalcSize(n.Type()) + w := n.Type().Size() + if w >= types.MaxWidth || w < 0 { + base.Fatalf("bad width") + } + if w == 0 && lastHasPtr { + // Pad between a pointer-containing object and a zero-sized object. + // This prevents a pointer to the zero-sized object from being interpreted + // as a pointer to the pointer-containing object (and causing it + // to be scanned when it shouldn't be). See issue 24993. + w = 1 + } + s.stksize += w + s.stksize = types.RoundUp(s.stksize, n.Type().Alignment()) + if n.Type().Alignment() > int64(types.RegSize) { + s.stkalign = n.Type().Alignment() + } + if n.Type().HasPointers() { + s.stkptrsize = s.stksize + lastHasPtr = true + } else { + lastHasPtr = false + } + n.SetFrameOffset(-s.stksize) + } + + s.stksize = types.RoundUp(s.stksize, s.stkalign) + s.stkptrsize = types.RoundUp(s.stkptrsize, s.stkalign) +} + +const maxStackSize = 1 << 30 + +// Compile builds an SSA backend function, +// uses it to generate a plist, +// and flushes that plist to machine code. +// worker indicates which of the backend workers is doing the processing. +func Compile(fn *ir.Func, worker int) { + f := buildssa(fn, worker) + // Note: check arg size to fix issue 25507. + if f.Frontend().(*ssafn).stksize >= maxStackSize || f.OwnAux.ArgWidth() >= maxStackSize { + largeStackFramesMu.Lock() + largeStackFrames = append(largeStackFrames, largeStack{locals: f.Frontend().(*ssafn).stksize, args: f.OwnAux.ArgWidth(), pos: fn.Pos()}) + largeStackFramesMu.Unlock() + return + } + pp := objw.NewProgs(fn, worker) + defer pp.Free() + genssa(f, pp) + // Check frame size again. + // The check above included only the space needed for local variables. + // After genssa, the space needed includes local variables and the callee arg region. + // We must do this check prior to calling pp.Flush. + // If there are any oversized stack frames, + // the assembler may emit inscrutable complaints about invalid instructions. + if pp.Text.To.Offset >= maxStackSize { + largeStackFramesMu.Lock() + locals := f.Frontend().(*ssafn).stksize + largeStackFrames = append(largeStackFrames, largeStack{locals: locals, args: f.OwnAux.ArgWidth(), callee: pp.Text.To.Offset - locals, pos: fn.Pos()}) + largeStackFramesMu.Unlock() + return + } + + pp.Flush() // assemble, fill in boilerplate, etc. + + // If we're compiling the package init function, search for any + // relocations that target global map init outline functions and + // turn them into weak relocs. + if fn.IsPackageInit() && base.Debug.WrapGlobalMapCtl != 1 { + weakenGlobalMapInitRelocs(fn) + } + + // fieldtrack must be called after pp.Flush. See issue 20014. + fieldtrack(pp.Text.From.Sym, fn.FieldTrack) +} + +// globalMapInitLsyms records the LSym of each map.init.NNN outlined +// map initializer function created by the compiler. +var globalMapInitLsyms map[*obj.LSym]struct{} + +// RegisterMapInitLsym records "s" in the set of outlined map initializer +// functions. +func RegisterMapInitLsym(s *obj.LSym) { + if globalMapInitLsyms == nil { + globalMapInitLsyms = make(map[*obj.LSym]struct{}) + } + globalMapInitLsyms[s] = struct{}{} +} + +// weakenGlobalMapInitRelocs walks through all of the relocations on a +// given a package init function "fn" and looks for relocs that target +// outlined global map initializer functions; if it finds any such +// relocs, it flags them as R_WEAK. +func weakenGlobalMapInitRelocs(fn *ir.Func) { + if globalMapInitLsyms == nil { + return + } + for i := range fn.LSym.R { + tgt := fn.LSym.R[i].Sym + if tgt == nil { + continue + } + if _, ok := globalMapInitLsyms[tgt]; !ok { + continue + } + if base.Debug.WrapGlobalMapDbg > 1 { + fmt.Fprintf(os.Stderr, "=-= weakify fn %v reloc %d %+v\n", fn, i, + fn.LSym.R[i]) + } + // set the R_WEAK bit, leave rest of reloc type intact + fn.LSym.R[i].Type |= objabi.R_WEAK + } +} + +// StackOffset returns the stack location of a LocalSlot relative to the +// stack pointer, suitable for use in a DWARF location entry. This has nothing +// to do with its offset in the user variable. +func StackOffset(slot ssa.LocalSlot) int32 { + n := slot.N + var off int64 + switch n.Class { + case ir.PPARAM, ir.PPARAMOUT: + if !n.IsOutputParamInRegisters() { + off = n.FrameOffset() + base.Ctxt.Arch.FixedFrameSize + break + } + fallthrough // PPARAMOUT in registers allocates like an AUTO + case ir.PAUTO: + off = n.FrameOffset() + if base.Ctxt.Arch.FixedFrameSize == 0 { + off -= int64(types.PtrSize) + } + if buildcfg.FramePointerEnabled { + off -= int64(types.PtrSize) + } + } + return int32(off + slot.Off) +} + +// fieldtrack adds R_USEFIELD relocations to fnsym to record any +// struct fields that it used. +func fieldtrack(fnsym *obj.LSym, tracked map[*obj.LSym]struct{}) { + if fnsym == nil { + return + } + if !buildcfg.Experiment.FieldTrack || len(tracked) == 0 { + return + } + + trackSyms := make([]*obj.LSym, 0, len(tracked)) + for sym := range tracked { + trackSyms = append(trackSyms, sym) + } + sort.Slice(trackSyms, func(i, j int) bool { return trackSyms[i].Name < trackSyms[j].Name }) + for _, sym := range trackSyms { + r := obj.Addrel(fnsym) + r.Sym = sym + r.Type = objabi.R_USEFIELD + } +} + +// largeStack is info about a function whose stack frame is too large (rare). +type largeStack struct { + locals int64 + args int64 + callee int64 + pos src.XPos +} + +var ( + largeStackFramesMu sync.Mutex // protects largeStackFrames + largeStackFrames []largeStack +) + +func CheckLargeStacks() { + // Check whether any of the functions we have compiled have gigantic stack frames. + sort.Slice(largeStackFrames, func(i, j int) bool { + return largeStackFrames[i].pos.Before(largeStackFrames[j].pos) + }) + for _, large := range largeStackFrames { + if large.callee != 0 { + base.ErrorfAt(large.pos, 0, "stack frame too large (>1GB): %d MB locals + %d MB args + %d MB callee", large.locals>>20, large.args>>20, large.callee>>20) + } else { + base.ErrorfAt(large.pos, 0, "stack frame too large (>1GB): %d MB locals + %d MB args", large.locals>>20, large.args>>20) + } + } +} diff --git a/src/cmd/compile/internal/ssagen/phi.go b/src/cmd/compile/internal/ssagen/phi.go new file mode 100644 index 0000000..19b6920 --- /dev/null +++ b/src/cmd/compile/internal/ssagen/phi.go @@ -0,0 +1,557 @@ +// 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 ssagen + +import ( + "container/heap" + "fmt" + + "cmd/compile/internal/ir" + "cmd/compile/internal/ssa" + "cmd/compile/internal/types" + "cmd/internal/src" +) + +// This file contains the algorithm to place phi nodes in a function. +// For small functions, we use Braun, Buchwald, Hack, Leißa, Mallon, and Zwinkau. +// https://pp.info.uni-karlsruhe.de/uploads/publikationen/braun13cc.pdf +// For large functions, we use Sreedhar & Gao: A Linear Time Algorithm for Placing Φ-Nodes. +// http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.8.1979&rep=rep1&type=pdf + +const smallBlocks = 500 + +const debugPhi = false + +// fwdRefAux wraps an arbitrary ir.Node as an ssa.Aux for use with OpFwdref. +type fwdRefAux struct { + _ [0]func() // ensure ir.Node isn't compared for equality + N ir.Node +} + +func (fwdRefAux) CanBeAnSSAAux() {} + +// insertPhis finds all the places in the function where a phi is +// necessary and inserts them. +// Uses FwdRef ops to find all uses of variables, and s.defvars to find +// all definitions. +// Phi values are inserted, and all FwdRefs are changed to a Copy +// of the appropriate phi or definition. +// TODO: make this part of cmd/compile/internal/ssa somehow? +func (s *state) insertPhis() { + if len(s.f.Blocks) <= smallBlocks { + sps := simplePhiState{s: s, f: s.f, defvars: s.defvars} + sps.insertPhis() + return + } + ps := phiState{s: s, f: s.f, defvars: s.defvars} + ps.insertPhis() +} + +type phiState struct { + s *state // SSA state + f *ssa.Func // function to work on + defvars []map[ir.Node]*ssa.Value // defined variables at end of each block + + varnum map[ir.Node]int32 // variable numbering + + // properties of the dominator tree + idom []*ssa.Block // dominator parents + tree []domBlock // dominator child+sibling + level []int32 // level in dominator tree (0 = root or unreachable, 1 = children of root, ...) + + // scratch locations + priq blockHeap // priority queue of blocks, higher level (toward leaves) = higher priority + q []*ssa.Block // inner loop queue + queued *sparseSet // has been put in q + hasPhi *sparseSet // has a phi + hasDef *sparseSet // has a write of the variable we're processing + + // miscellaneous + placeholder *ssa.Value // value to use as a "not set yet" placeholder. +} + +func (s *phiState) insertPhis() { + if debugPhi { + fmt.Println(s.f.String()) + } + + // Find all the variables for which we need to match up reads & writes. + // This step prunes any basic-block-only variables from consideration. + // Generate a numbering for these variables. + s.varnum = map[ir.Node]int32{} + var vars []ir.Node + var vartypes []*types.Type + for _, b := range s.f.Blocks { + for _, v := range b.Values { + if v.Op != ssa.OpFwdRef { + continue + } + var_ := v.Aux.(fwdRefAux).N + + // Optimization: look back 1 block for the definition. + if len(b.Preds) == 1 { + c := b.Preds[0].Block() + if w := s.defvars[c.ID][var_]; w != nil { + v.Op = ssa.OpCopy + v.Aux = nil + v.AddArg(w) + continue + } + } + + if _, ok := s.varnum[var_]; ok { + continue + } + s.varnum[var_] = int32(len(vartypes)) + if debugPhi { + fmt.Printf("var%d = %v\n", len(vartypes), var_) + } + vars = append(vars, var_) + vartypes = append(vartypes, v.Type) + } + } + + if len(vartypes) == 0 { + return + } + + // Find all definitions of the variables we need to process. + // defs[n] contains all the blocks in which variable number n is assigned. + defs := make([][]*ssa.Block, len(vartypes)) + for _, b := range s.f.Blocks { + for var_ := range s.defvars[b.ID] { // TODO: encode defvars some other way (explicit ops)? make defvars[n] a slice instead of a map. + if n, ok := s.varnum[var_]; ok { + defs[n] = append(defs[n], b) + } + } + } + + // Make dominator tree. + s.idom = s.f.Idom() + s.tree = make([]domBlock, s.f.NumBlocks()) + for _, b := range s.f.Blocks { + p := s.idom[b.ID] + if p != nil { + s.tree[b.ID].sibling = s.tree[p.ID].firstChild + s.tree[p.ID].firstChild = b + } + } + // Compute levels in dominator tree. + // With parent pointers we can do a depth-first walk without + // any auxiliary storage. + s.level = make([]int32, s.f.NumBlocks()) + b := s.f.Entry +levels: + for { + if p := s.idom[b.ID]; p != nil { + s.level[b.ID] = s.level[p.ID] + 1 + if debugPhi { + fmt.Printf("level %s = %d\n", b, s.level[b.ID]) + } + } + if c := s.tree[b.ID].firstChild; c != nil { + b = c + continue + } + for { + if c := s.tree[b.ID].sibling; c != nil { + b = c + continue levels + } + b = s.idom[b.ID] + if b == nil { + break levels + } + } + } + + // Allocate scratch locations. + s.priq.level = s.level + s.q = make([]*ssa.Block, 0, s.f.NumBlocks()) + s.queued = newSparseSet(s.f.NumBlocks()) + s.hasPhi = newSparseSet(s.f.NumBlocks()) + s.hasDef = newSparseSet(s.f.NumBlocks()) + s.placeholder = s.s.entryNewValue0(ssa.OpUnknown, types.TypeInvalid) + + // Generate phi ops for each variable. + for n := range vartypes { + s.insertVarPhis(n, vars[n], defs[n], vartypes[n]) + } + + // Resolve FwdRefs to the correct write or phi. + s.resolveFwdRefs() + + // Erase variable numbers stored in AuxInt fields of phi ops. They are no longer needed. + for _, b := range s.f.Blocks { + for _, v := range b.Values { + if v.Op == ssa.OpPhi { + v.AuxInt = 0 + } + // Any remaining FwdRefs are dead code. + if v.Op == ssa.OpFwdRef { + v.Op = ssa.OpUnknown + v.Aux = nil + } + } + } +} + +func (s *phiState) insertVarPhis(n int, var_ ir.Node, defs []*ssa.Block, typ *types.Type) { + priq := &s.priq + q := s.q + queued := s.queued + queued.clear() + hasPhi := s.hasPhi + hasPhi.clear() + hasDef := s.hasDef + hasDef.clear() + + // Add defining blocks to priority queue. + for _, b := range defs { + priq.a = append(priq.a, b) + hasDef.add(b.ID) + if debugPhi { + fmt.Printf("def of var%d in %s\n", n, b) + } + } + heap.Init(priq) + + // Visit blocks defining variable n, from deepest to shallowest. + for len(priq.a) > 0 { + currentRoot := heap.Pop(priq).(*ssa.Block) + if debugPhi { + fmt.Printf("currentRoot %s\n", currentRoot) + } + // Walk subtree below definition. + // Skip subtrees we've done in previous iterations. + // Find edges exiting tree dominated by definition (the dominance frontier). + // Insert phis at target blocks. + if queued.contains(currentRoot.ID) { + s.s.Fatalf("root already in queue") + } + q = append(q, currentRoot) + queued.add(currentRoot.ID) + for len(q) > 0 { + b := q[len(q)-1] + q = q[:len(q)-1] + if debugPhi { + fmt.Printf(" processing %s\n", b) + } + + currentRootLevel := s.level[currentRoot.ID] + for _, e := range b.Succs { + c := e.Block() + // TODO: if the variable is dead at c, skip it. + if s.level[c.ID] > currentRootLevel { + // a D-edge, or an edge whose target is in currentRoot's subtree. + continue + } + if hasPhi.contains(c.ID) { + continue + } + // Add a phi to block c for variable n. + hasPhi.add(c.ID) + v := c.NewValue0I(currentRoot.Pos, ssa.OpPhi, typ, int64(n)) // TODO: line number right? + // Note: we store the variable number in the phi's AuxInt field. Used temporarily by phi building. + if var_.Op() == ir.ONAME { + s.s.addNamedValue(var_.(*ir.Name), v) + } + for range c.Preds { + v.AddArg(s.placeholder) // Actual args will be filled in by resolveFwdRefs. + } + if debugPhi { + fmt.Printf("new phi for var%d in %s: %s\n", n, c, v) + } + if !hasDef.contains(c.ID) { + // There's now a new definition of this variable in block c. + // Add it to the priority queue to explore. + heap.Push(priq, c) + hasDef.add(c.ID) + } + } + + // Visit children if they have not been visited yet. + for c := s.tree[b.ID].firstChild; c != nil; c = s.tree[c.ID].sibling { + if !queued.contains(c.ID) { + q = append(q, c) + queued.add(c.ID) + } + } + } + } +} + +// resolveFwdRefs links all FwdRef uses up to their nearest dominating definition. +func (s *phiState) resolveFwdRefs() { + // Do a depth-first walk of the dominator tree, keeping track + // of the most-recently-seen value for each variable. + + // Map from variable ID to SSA value at the current point of the walk. + values := make([]*ssa.Value, len(s.varnum)) + for i := range values { + values[i] = s.placeholder + } + + // Stack of work to do. + type stackEntry struct { + b *ssa.Block // block to explore + + // variable/value pair to reinstate on exit + n int32 // variable ID + v *ssa.Value + + // Note: only one of b or n,v will be set. + } + var stk []stackEntry + + stk = append(stk, stackEntry{b: s.f.Entry}) + for len(stk) > 0 { + work := stk[len(stk)-1] + stk = stk[:len(stk)-1] + + b := work.b + if b == nil { + // On exit from a block, this case will undo any assignments done below. + values[work.n] = work.v + continue + } + + // Process phis as new defs. They come before FwdRefs in this block. + for _, v := range b.Values { + if v.Op != ssa.OpPhi { + continue + } + n := int32(v.AuxInt) + // Remember the old assignment so we can undo it when we exit b. + stk = append(stk, stackEntry{n: n, v: values[n]}) + // Record the new assignment. + values[n] = v + } + + // Replace a FwdRef op with the current incoming value for its variable. + for _, v := range b.Values { + if v.Op != ssa.OpFwdRef { + continue + } + n := s.varnum[v.Aux.(fwdRefAux).N] + v.Op = ssa.OpCopy + v.Aux = nil + v.AddArg(values[n]) + } + + // Establish values for variables defined in b. + for var_, v := range s.defvars[b.ID] { + n, ok := s.varnum[var_] + if !ok { + // some variable not live across a basic block boundary. + continue + } + // Remember the old assignment so we can undo it when we exit b. + stk = append(stk, stackEntry{n: n, v: values[n]}) + // Record the new assignment. + values[n] = v + } + + // Replace phi args in successors with the current incoming value. + for _, e := range b.Succs { + c, i := e.Block(), e.Index() + for j := len(c.Values) - 1; j >= 0; j-- { + v := c.Values[j] + if v.Op != ssa.OpPhi { + break // All phis will be at the end of the block during phi building. + } + // Only set arguments that have been resolved. + // For very wide CFGs, this significantly speeds up phi resolution. + // See golang.org/issue/8225. + if w := values[v.AuxInt]; w.Op != ssa.OpUnknown { + v.SetArg(i, w) + } + } + } + + // Walk children in dominator tree. + for c := s.tree[b.ID].firstChild; c != nil; c = s.tree[c.ID].sibling { + stk = append(stk, stackEntry{b: c}) + } + } +} + +// domBlock contains extra per-block information to record the dominator tree. +type domBlock struct { + firstChild *ssa.Block // first child of block in dominator tree + sibling *ssa.Block // next child of parent in dominator tree +} + +// A block heap is used as a priority queue to implement the PiggyBank +// from Sreedhar and Gao. That paper uses an array which is better +// asymptotically but worse in the common case when the PiggyBank +// holds a sparse set of blocks. +type blockHeap struct { + a []*ssa.Block // block IDs in heap + level []int32 // depth in dominator tree (static, used for determining priority) +} + +func (h *blockHeap) Len() int { return len(h.a) } +func (h *blockHeap) Swap(i, j int) { a := h.a; a[i], a[j] = a[j], a[i] } + +func (h *blockHeap) Push(x interface{}) { + v := x.(*ssa.Block) + h.a = append(h.a, v) +} +func (h *blockHeap) Pop() interface{} { + old := h.a + n := len(old) + x := old[n-1] + h.a = old[:n-1] + return x +} +func (h *blockHeap) Less(i, j int) bool { + return h.level[h.a[i].ID] > h.level[h.a[j].ID] +} + +// TODO: stop walking the iterated domininance frontier when +// the variable is dead. Maybe detect that by checking if the +// node we're on is reverse dominated by all the reads? +// Reverse dominated by the highest common successor of all the reads? + +// copy of ../ssa/sparseset.go +// TODO: move this file to ../ssa, then use sparseSet there. +type sparseSet struct { + dense []ssa.ID + sparse []int32 +} + +// newSparseSet returns a sparseSet that can represent +// integers between 0 and n-1. +func newSparseSet(n int) *sparseSet { + return &sparseSet{dense: nil, sparse: make([]int32, n)} +} + +func (s *sparseSet) contains(x ssa.ID) bool { + i := s.sparse[x] + return i < int32(len(s.dense)) && s.dense[i] == x +} + +func (s *sparseSet) add(x ssa.ID) { + i := s.sparse[x] + if i < int32(len(s.dense)) && s.dense[i] == x { + return + } + s.dense = append(s.dense, x) + s.sparse[x] = int32(len(s.dense)) - 1 +} + +func (s *sparseSet) clear() { + s.dense = s.dense[:0] +} + +// Variant to use for small functions. +type simplePhiState struct { + s *state // SSA state + f *ssa.Func // function to work on + fwdrefs []*ssa.Value // list of FwdRefs to be processed + defvars []map[ir.Node]*ssa.Value // defined variables at end of each block + reachable []bool // which blocks are reachable +} + +func (s *simplePhiState) insertPhis() { + s.reachable = ssa.ReachableBlocks(s.f) + + // Find FwdRef ops. + for _, b := range s.f.Blocks { + for _, v := range b.Values { + if v.Op != ssa.OpFwdRef { + continue + } + s.fwdrefs = append(s.fwdrefs, v) + var_ := v.Aux.(fwdRefAux).N + if _, ok := s.defvars[b.ID][var_]; !ok { + s.defvars[b.ID][var_] = v // treat FwdDefs as definitions. + } + } + } + + var args []*ssa.Value + +loop: + for len(s.fwdrefs) > 0 { + v := s.fwdrefs[len(s.fwdrefs)-1] + s.fwdrefs = s.fwdrefs[:len(s.fwdrefs)-1] + b := v.Block + var_ := v.Aux.(fwdRefAux).N + if b == s.f.Entry { + // No variable should be live at entry. + s.s.Fatalf("value %v (%v) incorrectly live at entry", var_, v) + } + if !s.reachable[b.ID] { + // This block is dead. + // It doesn't matter what we use here as long as it is well-formed. + v.Op = ssa.OpUnknown + v.Aux = nil + continue + } + // Find variable value on each predecessor. + args = args[:0] + for _, e := range b.Preds { + args = append(args, s.lookupVarOutgoing(e.Block(), v.Type, var_, v.Pos)) + } + + // Decide if we need a phi or not. We need a phi if there + // are two different args (which are both not v). + var w *ssa.Value + for _, a := range args { + if a == v { + continue // self-reference + } + if a == w { + continue // already have this witness + } + if w != nil { + // two witnesses, need a phi value + v.Op = ssa.OpPhi + v.AddArgs(args...) + v.Aux = nil + continue loop + } + w = a // save witness + } + if w == nil { + s.s.Fatalf("no witness for reachable phi %s", v) + } + // One witness. Make v a copy of w. + v.Op = ssa.OpCopy + v.Aux = nil + v.AddArg(w) + } +} + +// lookupVarOutgoing finds the variable's value at the end of block b. +func (s *simplePhiState) lookupVarOutgoing(b *ssa.Block, t *types.Type, var_ ir.Node, line src.XPos) *ssa.Value { + for { + if v := s.defvars[b.ID][var_]; v != nil { + return v + } + // The variable is not defined by b and we haven't looked it up yet. + // If b has exactly one predecessor, loop to look it up there. + // Otherwise, give up and insert a new FwdRef and resolve it later. + if len(b.Preds) != 1 { + break + } + b = b.Preds[0].Block() + if !s.reachable[b.ID] { + // This is rare; it happens with oddly interleaved infinite loops in dead code. + // See issue 19783. + break + } + } + // Generate a FwdRef for the variable and return that. + v := b.NewValue0A(line, ssa.OpFwdRef, t, fwdRefAux{N: var_}) + s.defvars[b.ID][var_] = v + if var_.Op() == ir.ONAME { + s.s.addNamedValue(var_.(*ir.Name), v) + } + s.fwdrefs = append(s.fwdrefs, v) + return v +} diff --git a/src/cmd/compile/internal/ssagen/ssa.go b/src/cmd/compile/internal/ssagen/ssa.go new file mode 100644 index 0000000..e994577 --- /dev/null +++ b/src/cmd/compile/internal/ssagen/ssa.go @@ -0,0 +1,8150 @@ +// Copyright 2015 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 ssagen + +import ( + "bufio" + "bytes" + "fmt" + "go/constant" + "html" + "internal/buildcfg" + "os" + "path/filepath" + "sort" + "strings" + + "cmd/compile/internal/abi" + "cmd/compile/internal/base" + "cmd/compile/internal/ir" + "cmd/compile/internal/liveness" + "cmd/compile/internal/objw" + "cmd/compile/internal/reflectdata" + "cmd/compile/internal/ssa" + "cmd/compile/internal/staticdata" + "cmd/compile/internal/typecheck" + "cmd/compile/internal/types" + "cmd/internal/obj" + "cmd/internal/src" + "cmd/internal/sys" + + rtabi "internal/abi" +) + +var ssaConfig *ssa.Config +var ssaCaches []ssa.Cache + +var ssaDump string // early copy of $GOSSAFUNC; the func name to dump output for +var ssaDir string // optional destination for ssa dump file +var ssaDumpStdout bool // whether to dump to stdout +var ssaDumpCFG string // generate CFGs for these phases +const ssaDumpFile = "ssa.html" + +// ssaDumpInlined holds all inlined functions when ssaDump contains a function name. +var ssaDumpInlined []*ir.Func + +func DumpInline(fn *ir.Func) { + if ssaDump != "" && ssaDump == ir.FuncName(fn) { + ssaDumpInlined = append(ssaDumpInlined, fn) + } +} + +func InitEnv() { + ssaDump = os.Getenv("GOSSAFUNC") + ssaDir = os.Getenv("GOSSADIR") + if ssaDump != "" { + if strings.HasSuffix(ssaDump, "+") { + ssaDump = ssaDump[:len(ssaDump)-1] + ssaDumpStdout = true + } + spl := strings.Split(ssaDump, ":") + if len(spl) > 1 { + ssaDump = spl[0] + ssaDumpCFG = spl[1] + } + } +} + +func InitConfig() { + types_ := ssa.NewTypes() + + if Arch.SoftFloat { + softfloatInit() + } + + // Generate a few pointer types that are uncommon in the frontend but common in the backend. + // Caching is disabled in the backend, so generating these here avoids allocations. + _ = types.NewPtr(types.Types[types.TINTER]) // *interface{} + _ = types.NewPtr(types.NewPtr(types.Types[types.TSTRING])) // **string + _ = types.NewPtr(types.NewSlice(types.Types[types.TINTER])) // *[]interface{} + _ = types.NewPtr(types.NewPtr(types.ByteType)) // **byte + _ = types.NewPtr(types.NewSlice(types.ByteType)) // *[]byte + _ = types.NewPtr(types.NewSlice(types.Types[types.TSTRING])) // *[]string + _ = types.NewPtr(types.NewPtr(types.NewPtr(types.Types[types.TUINT8]))) // ***uint8 + _ = types.NewPtr(types.Types[types.TINT16]) // *int16 + _ = types.NewPtr(types.Types[types.TINT64]) // *int64 + _ = types.NewPtr(types.ErrorType) // *error + types.NewPtrCacheEnabled = false + ssaConfig = ssa.NewConfig(base.Ctxt.Arch.Name, *types_, base.Ctxt, base.Flag.N == 0, Arch.SoftFloat) + ssaConfig.Race = base.Flag.Race + ssaCaches = make([]ssa.Cache, base.Flag.LowerC) + + // Set up some runtime functions we'll need to call. + ir.Syms.AssertE2I = typecheck.LookupRuntimeFunc("assertE2I") + ir.Syms.AssertE2I2 = typecheck.LookupRuntimeFunc("assertE2I2") + ir.Syms.AssertI2I = typecheck.LookupRuntimeFunc("assertI2I") + ir.Syms.AssertI2I2 = typecheck.LookupRuntimeFunc("assertI2I2") + ir.Syms.CgoCheckMemmove = typecheck.LookupRuntimeFunc("cgoCheckMemmove") + ir.Syms.CgoCheckPtrWrite = typecheck.LookupRuntimeFunc("cgoCheckPtrWrite") + ir.Syms.CheckPtrAlignment = typecheck.LookupRuntimeFunc("checkptrAlignment") + ir.Syms.Deferproc = typecheck.LookupRuntimeFunc("deferproc") + ir.Syms.DeferprocStack = typecheck.LookupRuntimeFunc("deferprocStack") + ir.Syms.Deferreturn = typecheck.LookupRuntimeFunc("deferreturn") + ir.Syms.Duffcopy = typecheck.LookupRuntimeFunc("duffcopy") + ir.Syms.Duffzero = typecheck.LookupRuntimeFunc("duffzero") + ir.Syms.GCWriteBarrier[0] = typecheck.LookupRuntimeFunc("gcWriteBarrier1") + ir.Syms.GCWriteBarrier[1] = typecheck.LookupRuntimeFunc("gcWriteBarrier2") + ir.Syms.GCWriteBarrier[2] = typecheck.LookupRuntimeFunc("gcWriteBarrier3") + ir.Syms.GCWriteBarrier[3] = typecheck.LookupRuntimeFunc("gcWriteBarrier4") + ir.Syms.GCWriteBarrier[4] = typecheck.LookupRuntimeFunc("gcWriteBarrier5") + ir.Syms.GCWriteBarrier[5] = typecheck.LookupRuntimeFunc("gcWriteBarrier6") + ir.Syms.GCWriteBarrier[6] = typecheck.LookupRuntimeFunc("gcWriteBarrier7") + ir.Syms.GCWriteBarrier[7] = typecheck.LookupRuntimeFunc("gcWriteBarrier8") + ir.Syms.Goschedguarded = typecheck.LookupRuntimeFunc("goschedguarded") + ir.Syms.Growslice = typecheck.LookupRuntimeFunc("growslice") + ir.Syms.Memmove = typecheck.LookupRuntimeFunc("memmove") + ir.Syms.Msanread = typecheck.LookupRuntimeFunc("msanread") + ir.Syms.Msanwrite = typecheck.LookupRuntimeFunc("msanwrite") + ir.Syms.Msanmove = typecheck.LookupRuntimeFunc("msanmove") + ir.Syms.Asanread = typecheck.LookupRuntimeFunc("asanread") + ir.Syms.Asanwrite = typecheck.LookupRuntimeFunc("asanwrite") + ir.Syms.Newobject = typecheck.LookupRuntimeFunc("newobject") + ir.Syms.Newproc = typecheck.LookupRuntimeFunc("newproc") + ir.Syms.Panicdivide = typecheck.LookupRuntimeFunc("panicdivide") + ir.Syms.PanicdottypeE = typecheck.LookupRuntimeFunc("panicdottypeE") + ir.Syms.PanicdottypeI = typecheck.LookupRuntimeFunc("panicdottypeI") + ir.Syms.Panicnildottype = typecheck.LookupRuntimeFunc("panicnildottype") + ir.Syms.Panicoverflow = typecheck.LookupRuntimeFunc("panicoverflow") + ir.Syms.Panicshift = typecheck.LookupRuntimeFunc("panicshift") + ir.Syms.Raceread = typecheck.LookupRuntimeFunc("raceread") + ir.Syms.Racereadrange = typecheck.LookupRuntimeFunc("racereadrange") + ir.Syms.Racewrite = typecheck.LookupRuntimeFunc("racewrite") + ir.Syms.Racewriterange = typecheck.LookupRuntimeFunc("racewriterange") + ir.Syms.WBZero = typecheck.LookupRuntimeFunc("wbZero") + ir.Syms.WBMove = typecheck.LookupRuntimeFunc("wbMove") + ir.Syms.X86HasPOPCNT = typecheck.LookupRuntimeVar("x86HasPOPCNT") // bool + ir.Syms.X86HasSSE41 = typecheck.LookupRuntimeVar("x86HasSSE41") // bool + ir.Syms.X86HasFMA = typecheck.LookupRuntimeVar("x86HasFMA") // bool + ir.Syms.ARMHasVFPv4 = typecheck.LookupRuntimeVar("armHasVFPv4") // bool + ir.Syms.ARM64HasATOMICS = typecheck.LookupRuntimeVar("arm64HasATOMICS") // bool + ir.Syms.Staticuint64s = typecheck.LookupRuntimeVar("staticuint64s") + ir.Syms.Typedmemmove = typecheck.LookupRuntimeFunc("typedmemmove") + ir.Syms.Udiv = typecheck.LookupRuntimeVar("udiv") // asm func with special ABI + ir.Syms.WriteBarrier = typecheck.LookupRuntimeVar("writeBarrier") // struct { bool; ... } + ir.Syms.Zerobase = typecheck.LookupRuntimeVar("zerobase") + + if Arch.LinkArch.Family == sys.Wasm { + BoundsCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeFunc("goPanicIndex") + BoundsCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeFunc("goPanicIndexU") + BoundsCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeFunc("goPanicSliceAlen") + BoundsCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeFunc("goPanicSliceAlenU") + BoundsCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeFunc("goPanicSliceAcap") + BoundsCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeFunc("goPanicSliceAcapU") + BoundsCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeFunc("goPanicSliceB") + BoundsCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeFunc("goPanicSliceBU") + BoundsCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeFunc("goPanicSlice3Alen") + BoundsCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeFunc("goPanicSlice3AlenU") + BoundsCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeFunc("goPanicSlice3Acap") + BoundsCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeFunc("goPanicSlice3AcapU") + BoundsCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeFunc("goPanicSlice3B") + BoundsCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeFunc("goPanicSlice3BU") + BoundsCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeFunc("goPanicSlice3C") + BoundsCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeFunc("goPanicSlice3CU") + BoundsCheckFunc[ssa.BoundsConvert] = typecheck.LookupRuntimeFunc("goPanicSliceConvert") + } else { + BoundsCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeFunc("panicIndex") + BoundsCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeFunc("panicIndexU") + BoundsCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeFunc("panicSliceAlen") + BoundsCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeFunc("panicSliceAlenU") + BoundsCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeFunc("panicSliceAcap") + BoundsCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeFunc("panicSliceAcapU") + BoundsCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeFunc("panicSliceB") + BoundsCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeFunc("panicSliceBU") + BoundsCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeFunc("panicSlice3Alen") + BoundsCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeFunc("panicSlice3AlenU") + BoundsCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeFunc("panicSlice3Acap") + BoundsCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeFunc("panicSlice3AcapU") + BoundsCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeFunc("panicSlice3B") + BoundsCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeFunc("panicSlice3BU") + BoundsCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeFunc("panicSlice3C") + BoundsCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeFunc("panicSlice3CU") + BoundsCheckFunc[ssa.BoundsConvert] = typecheck.LookupRuntimeFunc("panicSliceConvert") + } + if Arch.LinkArch.PtrSize == 4 { + ExtendCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeVar("panicExtendIndex") + ExtendCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeVar("panicExtendIndexU") + ExtendCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeVar("panicExtendSliceAlen") + ExtendCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeVar("panicExtendSliceAlenU") + ExtendCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeVar("panicExtendSliceAcap") + ExtendCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeVar("panicExtendSliceAcapU") + ExtendCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeVar("panicExtendSliceB") + ExtendCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeVar("panicExtendSliceBU") + ExtendCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeVar("panicExtendSlice3Alen") + ExtendCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeVar("panicExtendSlice3AlenU") + ExtendCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeVar("panicExtendSlice3Acap") + ExtendCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeVar("panicExtendSlice3AcapU") + ExtendCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeVar("panicExtendSlice3B") + ExtendCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeVar("panicExtendSlice3BU") + ExtendCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeVar("panicExtendSlice3C") + ExtendCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeVar("panicExtendSlice3CU") + } + + // Wasm (all asm funcs with special ABIs) + ir.Syms.WasmDiv = typecheck.LookupRuntimeVar("wasmDiv") + ir.Syms.WasmTruncS = typecheck.LookupRuntimeVar("wasmTruncS") + ir.Syms.WasmTruncU = typecheck.LookupRuntimeVar("wasmTruncU") + ir.Syms.SigPanic = typecheck.LookupRuntimeFunc("sigpanic") +} + +// AbiForBodylessFuncStackMap returns the ABI for a bodyless function's stack map. +// This is not necessarily the ABI used to call it. +// Currently (1.17 dev) such a stack map is always ABI0; +// any ABI wrapper that is present is nosplit, hence a precise +// stack map is not needed there (the parameters survive only long +// enough to call the wrapped assembly function). +// This always returns a freshly copied ABI. +func AbiForBodylessFuncStackMap(fn *ir.Func) *abi.ABIConfig { + return ssaConfig.ABI0.Copy() // No idea what races will result, be safe +} + +// abiForFunc implements ABI policy for a function, but does not return a copy of the ABI. +// Passing a nil function returns the default ABI based on experiment configuration. +func abiForFunc(fn *ir.Func, abi0, abi1 *abi.ABIConfig) *abi.ABIConfig { + if buildcfg.Experiment.RegabiArgs { + // Select the ABI based on the function's defining ABI. + if fn == nil { + return abi1 + } + switch fn.ABI { + case obj.ABI0: + return abi0 + case obj.ABIInternal: + // TODO(austin): Clean up the nomenclature here. + // It's not clear that "abi1" is ABIInternal. + return abi1 + } + base.Fatalf("function %v has unknown ABI %v", fn, fn.ABI) + panic("not reachable") + } + + a := abi0 + if fn != nil { + if fn.Pragma&ir.RegisterParams != 0 { // TODO(register args) remove after register abi is working + a = abi1 + } + } + return a +} + +// dvarint writes a varint v to the funcdata in symbol x and returns the new offset. +func dvarint(x *obj.LSym, off int, v int64) int { + if v < 0 || v > 1e9 { + panic(fmt.Sprintf("dvarint: bad offset for funcdata - %v", v)) + } + if v < 1<<7 { + return objw.Uint8(x, off, uint8(v)) + } + off = objw.Uint8(x, off, uint8((v&127)|128)) + if v < 1<<14 { + return objw.Uint8(x, off, uint8(v>>7)) + } + off = objw.Uint8(x, off, uint8(((v>>7)&127)|128)) + if v < 1<<21 { + return objw.Uint8(x, off, uint8(v>>14)) + } + off = objw.Uint8(x, off, uint8(((v>>14)&127)|128)) + if v < 1<<28 { + return objw.Uint8(x, off, uint8(v>>21)) + } + off = objw.Uint8(x, off, uint8(((v>>21)&127)|128)) + return objw.Uint8(x, off, uint8(v>>28)) +} + +// emitOpenDeferInfo emits FUNCDATA information about the defers in a function +// that is using open-coded defers. This funcdata is used to determine the active +// defers in a function and execute those defers during panic processing. +// +// The funcdata is all encoded in varints (since values will almost always be less than +// 128, but stack offsets could potentially be up to 2Gbyte). All "locations" (offsets) +// for stack variables are specified as the number of bytes below varp (pointer to the +// top of the local variables) for their starting address. The format is: +// +// - Offset of the deferBits variable +// - Number of defers in the function +// - Information about each defer call, in reverse order of appearance in the function: +// - Offset of the closure value to call +func (s *state) emitOpenDeferInfo() { + x := base.Ctxt.Lookup(s.curfn.LSym.Name + ".opendefer") + x.Set(obj.AttrContentAddressable, true) + s.curfn.LSym.Func().OpenCodedDeferInfo = x + off := 0 + off = dvarint(x, off, -s.deferBitsTemp.FrameOffset()) + off = dvarint(x, off, int64(len(s.openDefers))) + + // Write in reverse-order, for ease of running in that order at runtime + for i := len(s.openDefers) - 1; i >= 0; i-- { + r := s.openDefers[i] + off = dvarint(x, off, -r.closureNode.FrameOffset()) + } +} + +func okOffset(offset int64) int64 { + if offset == types.BOGUS_FUNARG_OFFSET { + panic(fmt.Errorf("Bogus offset %d", offset)) + } + return offset +} + +// buildssa builds an SSA function for fn. +// worker indicates which of the backend workers is doing the processing. +func buildssa(fn *ir.Func, worker int) *ssa.Func { + name := ir.FuncName(fn) + printssa := false + if ssaDump != "" { // match either a simple name e.g. "(*Reader).Reset", package.name e.g. "compress/gzip.(*Reader).Reset", or subpackage name "gzip.(*Reader).Reset" + pkgDotName := base.Ctxt.Pkgpath + "." + name + printssa = name == ssaDump || + strings.HasSuffix(pkgDotName, ssaDump) && (pkgDotName == ssaDump || strings.HasSuffix(pkgDotName, "/"+ssaDump)) + } + var astBuf *bytes.Buffer + if printssa { + astBuf = &bytes.Buffer{} + ir.FDumpList(astBuf, "buildssa-enter", fn.Enter) + ir.FDumpList(astBuf, "buildssa-body", fn.Body) + ir.FDumpList(astBuf, "buildssa-exit", fn.Exit) + if ssaDumpStdout { + fmt.Println("generating SSA for", name) + fmt.Print(astBuf.String()) + } + } + + var s state + s.pushLine(fn.Pos()) + defer s.popLine() + + s.hasdefer = fn.HasDefer() + if fn.Pragma&ir.CgoUnsafeArgs != 0 { + s.cgoUnsafeArgs = true + } + s.checkPtrEnabled = ir.ShouldCheckPtr(fn, 1) + + fe := ssafn{ + curfn: fn, + log: printssa && ssaDumpStdout, + } + s.curfn = fn + + s.f = ssa.NewFunc(&fe) + s.config = ssaConfig + s.f.Type = fn.Type() + s.f.Config = ssaConfig + s.f.Cache = &ssaCaches[worker] + s.f.Cache.Reset() + s.f.Name = name + s.f.PrintOrHtmlSSA = printssa + if fn.Pragma&ir.Nosplit != 0 { + s.f.NoSplit = true + } + s.f.ABI0 = ssaConfig.ABI0.Copy() // Make a copy to avoid racy map operations in type-register-width cache. + s.f.ABI1 = ssaConfig.ABI1.Copy() + s.f.ABIDefault = abiForFunc(nil, s.f.ABI0, s.f.ABI1) + s.f.ABISelf = abiForFunc(fn, s.f.ABI0, s.f.ABI1) + + s.panics = map[funcLine]*ssa.Block{} + s.softFloat = s.config.SoftFloat + + // Allocate starting block + s.f.Entry = s.f.NewBlock(ssa.BlockPlain) + s.f.Entry.Pos = fn.Pos() + + if printssa { + ssaDF := ssaDumpFile + if ssaDir != "" { + ssaDF = filepath.Join(ssaDir, base.Ctxt.Pkgpath+"."+name+".html") + ssaD := filepath.Dir(ssaDF) + os.MkdirAll(ssaD, 0755) + } + s.f.HTMLWriter = ssa.NewHTMLWriter(ssaDF, s.f, ssaDumpCFG) + // TODO: generate and print a mapping from nodes to values and blocks + dumpSourcesColumn(s.f.HTMLWriter, fn) + s.f.HTMLWriter.WriteAST("AST", astBuf) + } + + // Allocate starting values + s.labels = map[string]*ssaLabel{} + s.fwdVars = map[ir.Node]*ssa.Value{} + s.startmem = s.entryNewValue0(ssa.OpInitMem, types.TypeMem) + + s.hasOpenDefers = base.Flag.N == 0 && s.hasdefer && !s.curfn.OpenCodedDeferDisallowed() + switch { + case base.Debug.NoOpenDefer != 0: + s.hasOpenDefers = false + case s.hasOpenDefers && (base.Ctxt.Flag_shared || base.Ctxt.Flag_dynlink) && base.Ctxt.Arch.Name == "386": + // Don't support open-coded defers for 386 ONLY when using shared + // libraries, because there is extra code (added by rewriteToUseGot()) + // preceding the deferreturn/ret code that we don't track correctly. + s.hasOpenDefers = false + } + if s.hasOpenDefers && len(s.curfn.Exit) > 0 { + // Skip doing open defers if there is any extra exit code (likely + // race detection), since we will not generate that code in the + // case of the extra deferreturn/ret segment. + s.hasOpenDefers = false + } + if s.hasOpenDefers { + // Similarly, skip if there are any heap-allocated result + // parameters that need to be copied back to their stack slots. + for _, f := range s.curfn.Type().Results().FieldSlice() { + if !f.Nname.(*ir.Name).OnStack() { + s.hasOpenDefers = false + break + } + } + } + if s.hasOpenDefers && + s.curfn.NumReturns*s.curfn.NumDefers > 15 { + // Since we are generating defer calls at every exit for + // open-coded defers, skip doing open-coded defers if there are + // too many returns (especially if there are multiple defers). + // Open-coded defers are most important for improving performance + // for smaller functions (which don't have many returns). + s.hasOpenDefers = false + } + + s.sp = s.entryNewValue0(ssa.OpSP, types.Types[types.TUINTPTR]) // TODO: use generic pointer type (unsafe.Pointer?) instead + s.sb = s.entryNewValue0(ssa.OpSB, types.Types[types.TUINTPTR]) + + s.startBlock(s.f.Entry) + s.vars[memVar] = s.startmem + if s.hasOpenDefers { + // Create the deferBits variable and stack slot. deferBits is a + // bitmask showing which of the open-coded defers in this function + // have been activated. + deferBitsTemp := typecheck.TempAt(src.NoXPos, s.curfn, types.Types[types.TUINT8]) + deferBitsTemp.SetAddrtaken(true) + s.deferBitsTemp = deferBitsTemp + // For this value, AuxInt is initialized to zero by default + startDeferBits := s.entryNewValue0(ssa.OpConst8, types.Types[types.TUINT8]) + s.vars[deferBitsVar] = startDeferBits + s.deferBitsAddr = s.addr(deferBitsTemp) + s.store(types.Types[types.TUINT8], s.deferBitsAddr, startDeferBits) + // Make sure that the deferBits stack slot is kept alive (for use + // by panics) and stores to deferBits are not eliminated, even if + // all checking code on deferBits in the function exit can be + // eliminated, because the defer statements were all + // unconditional. + s.vars[memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, deferBitsTemp, s.mem(), false) + } + + var params *abi.ABIParamResultInfo + params = s.f.ABISelf.ABIAnalyze(fn.Type(), true) + + // The backend's stackframe pass prunes away entries from the fn's + // Dcl list, including PARAMOUT nodes that correspond to output + // params passed in registers. Walk the Dcl list and capture these + // nodes to a side list, so that we'll have them available during + // DWARF-gen later on. See issue 48573 for more details. + var debugInfo ssa.FuncDebug + for _, n := range fn.Dcl { + if n.Class == ir.PPARAMOUT && n.IsOutputParamInRegisters() { + debugInfo.RegOutputParams = append(debugInfo.RegOutputParams, n) + } + } + fn.DebugInfo = &debugInfo + + // Generate addresses of local declarations + s.decladdrs = map[*ir.Name]*ssa.Value{} + for _, n := range fn.Dcl { + switch n.Class { + case ir.PPARAM: + // Be aware that blank and unnamed input parameters will not appear here, but do appear in the type + s.decladdrs[n] = s.entryNewValue2A(ssa.OpLocalAddr, types.NewPtr(n.Type()), n, s.sp, s.startmem) + case ir.PPARAMOUT: + s.decladdrs[n] = s.entryNewValue2A(ssa.OpLocalAddr, types.NewPtr(n.Type()), n, s.sp, s.startmem) + case ir.PAUTO: + // processed at each use, to prevent Addr coming + // before the decl. + default: + s.Fatalf("local variable with class %v unimplemented", n.Class) + } + } + + s.f.OwnAux = ssa.OwnAuxCall(fn.LSym, params) + + // Populate SSAable arguments. + for _, n := range fn.Dcl { + if n.Class == ir.PPARAM { + if s.canSSA(n) { + v := s.newValue0A(ssa.OpArg, n.Type(), n) + s.vars[n] = v + s.addNamedValue(n, v) // This helps with debugging information, not needed for compilation itself. + } else { // address was taken AND/OR too large for SSA + paramAssignment := ssa.ParamAssignmentForArgName(s.f, n) + if len(paramAssignment.Registers) > 0 { + if TypeOK(n.Type()) { // SSA-able type, so address was taken -- receive value in OpArg, DO NOT bind to var, store immediately to memory. + v := s.newValue0A(ssa.OpArg, n.Type(), n) + s.store(n.Type(), s.decladdrs[n], v) + } else { // Too big for SSA. + // Brute force, and early, do a bunch of stores from registers + // TODO fix the nasty storeArgOrLoad recursion in ssa/expand_calls.go so this Just Works with store of a big Arg. + s.storeParameterRegsToStack(s.f.ABISelf, paramAssignment, n, s.decladdrs[n], false) + } + } + } + } + } + + // Populate closure variables. + if fn.Needctxt() { + clo := s.entryNewValue0(ssa.OpGetClosurePtr, s.f.Config.Types.BytePtr) + offset := int64(types.PtrSize) // PtrSize to skip past function entry PC field + for _, n := range fn.ClosureVars { + typ := n.Type() + if !n.Byval() { + typ = types.NewPtr(typ) + } + + offset = types.RoundUp(offset, typ.Alignment()) + ptr := s.newValue1I(ssa.OpOffPtr, types.NewPtr(typ), offset, clo) + offset += typ.Size() + + // If n is a small variable captured by value, promote + // it to PAUTO so it can be converted to SSA. + // + // Note: While we never capture a variable by value if + // the user took its address, we may have generated + // runtime calls that did (#43701). Since we don't + // convert Addrtaken variables to SSA anyway, no point + // in promoting them either. + if n.Byval() && !n.Addrtaken() && TypeOK(n.Type()) { + n.Class = ir.PAUTO + fn.Dcl = append(fn.Dcl, n) + s.assign(n, s.load(n.Type(), ptr), false, 0) + continue + } + + if !n.Byval() { + ptr = s.load(typ, ptr) + } + s.setHeapaddr(fn.Pos(), n, ptr) + } + } + + // Convert the AST-based IR to the SSA-based IR + s.stmtList(fn.Enter) + s.zeroResults() + s.paramsToHeap() + s.stmtList(fn.Body) + + // fallthrough to exit + if s.curBlock != nil { + s.pushLine(fn.Endlineno) + s.exit() + s.popLine() + } + + for _, b := range s.f.Blocks { + if b.Pos != src.NoXPos { + s.updateUnsetPredPos(b) + } + } + + s.f.HTMLWriter.WritePhase("before insert phis", "before insert phis") + + s.insertPhis() + + // Main call to ssa package to compile function + ssa.Compile(s.f) + + if s.hasOpenDefers { + s.emitOpenDeferInfo() + } + + // Record incoming parameter spill information for morestack calls emitted in the assembler. + // This is done here, using all the parameters (used, partially used, and unused) because + // it mimics the behavior of the former ABI (everything stored) and because it's not 100% + // clear if naming conventions are respected in autogenerated code. + // TODO figure out exactly what's unused, don't spill it. Make liveness fine-grained, also. + for _, p := range params.InParams() { + typs, offs := p.RegisterTypesAndOffsets() + for i, t := range typs { + o := offs[i] // offset within parameter + fo := p.FrameOffset(params) // offset of parameter in frame + reg := ssa.ObjRegForAbiReg(p.Registers[i], s.f.Config) + s.f.RegArgs = append(s.f.RegArgs, ssa.Spill{Reg: reg, Offset: fo + o, Type: t}) + } + } + + return s.f +} + +func (s *state) storeParameterRegsToStack(abi *abi.ABIConfig, paramAssignment *abi.ABIParamAssignment, n *ir.Name, addr *ssa.Value, pointersOnly bool) { + typs, offs := paramAssignment.RegisterTypesAndOffsets() + for i, t := range typs { + if pointersOnly && !t.IsPtrShaped() { + continue + } + r := paramAssignment.Registers[i] + o := offs[i] + op, reg := ssa.ArgOpAndRegisterFor(r, abi) + aux := &ssa.AuxNameOffset{Name: n, Offset: o} + v := s.newValue0I(op, t, reg) + v.Aux = aux + p := s.newValue1I(ssa.OpOffPtr, types.NewPtr(t), o, addr) + s.store(t, p, v) + } +} + +// zeroResults zeros the return values at the start of the function. +// We need to do this very early in the function. Defer might stop a +// panic and show the return values as they exist at the time of +// panic. For precise stacks, the garbage collector assumes results +// are always live, so we need to zero them before any allocations, +// even allocations to move params/results to the heap. +func (s *state) zeroResults() { + for _, f := range s.curfn.Type().Results().FieldSlice() { + n := f.Nname.(*ir.Name) + if !n.OnStack() { + // The local which points to the return value is the + // thing that needs zeroing. This is already handled + // by a Needzero annotation in plive.go:(*liveness).epilogue. + continue + } + // Zero the stack location containing f. + if typ := n.Type(); TypeOK(typ) { + s.assign(n, s.zeroVal(typ), false, 0) + } else { + if typ.HasPointers() { + s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, n, s.mem()) + } + s.zero(n.Type(), s.decladdrs[n]) + } + } +} + +// paramsToHeap produces code to allocate memory for heap-escaped parameters +// and to copy non-result parameters' values from the stack. +func (s *state) paramsToHeap() { + do := func(params *types.Type) { + for _, f := range params.FieldSlice() { + if f.Nname == nil { + continue // anonymous or blank parameter + } + n := f.Nname.(*ir.Name) + if ir.IsBlank(n) || n.OnStack() { + continue + } + s.newHeapaddr(n) + if n.Class == ir.PPARAM { + s.move(n.Type(), s.expr(n.Heapaddr), s.decladdrs[n]) + } + } + } + + typ := s.curfn.Type() + do(typ.Recvs()) + do(typ.Params()) + do(typ.Results()) +} + +// newHeapaddr allocates heap memory for n and sets its heap address. +func (s *state) newHeapaddr(n *ir.Name) { + s.setHeapaddr(n.Pos(), n, s.newObject(n.Type(), nil)) +} + +// setHeapaddr allocates a new PAUTO variable to store ptr (which must be non-nil) +// and then sets it as n's heap address. +func (s *state) setHeapaddr(pos src.XPos, n *ir.Name, ptr *ssa.Value) { + if !ptr.Type.IsPtr() || !types.Identical(n.Type(), ptr.Type.Elem()) { + base.FatalfAt(n.Pos(), "setHeapaddr %L with type %v", n, ptr.Type) + } + + // Declare variable to hold address. + addr := ir.NewNameAt(pos, &types.Sym{Name: "&" + n.Sym().Name, Pkg: types.LocalPkg}) + addr.SetType(types.NewPtr(n.Type())) + addr.Class = ir.PAUTO + addr.SetUsed(true) + addr.Curfn = s.curfn + s.curfn.Dcl = append(s.curfn.Dcl, addr) + types.CalcSize(addr.Type()) + + if n.Class == ir.PPARAMOUT { + addr.SetIsOutputParamHeapAddr(true) + } + + n.Heapaddr = addr + s.assign(addr, ptr, false, 0) +} + +// newObject returns an SSA value denoting new(typ). +func (s *state) newObject(typ *types.Type, rtype *ssa.Value) *ssa.Value { + if typ.Size() == 0 { + return s.newValue1A(ssa.OpAddr, types.NewPtr(typ), ir.Syms.Zerobase, s.sb) + } + if rtype == nil { + rtype = s.reflectType(typ) + } + return s.rtcall(ir.Syms.Newobject, true, []*types.Type{types.NewPtr(typ)}, rtype)[0] +} + +func (s *state) checkPtrAlignment(n *ir.ConvExpr, v *ssa.Value, count *ssa.Value) { + if !n.Type().IsPtr() { + s.Fatalf("expected pointer type: %v", n.Type()) + } + elem, rtypeExpr := n.Type().Elem(), n.ElemRType + if count != nil { + if !elem.IsArray() { + s.Fatalf("expected array type: %v", elem) + } + elem, rtypeExpr = elem.Elem(), n.ElemElemRType + } + size := elem.Size() + // Casting from larger type to smaller one is ok, so for smallest type, do nothing. + if elem.Alignment() == 1 && (size == 0 || size == 1 || count == nil) { + return + } + if count == nil { + count = s.constInt(types.Types[types.TUINTPTR], 1) + } + if count.Type.Size() != s.config.PtrSize { + s.Fatalf("expected count fit to a uintptr size, have: %d, want: %d", count.Type.Size(), s.config.PtrSize) + } + var rtype *ssa.Value + if rtypeExpr != nil { + rtype = s.expr(rtypeExpr) + } else { + rtype = s.reflectType(elem) + } + s.rtcall(ir.Syms.CheckPtrAlignment, true, nil, v, rtype, count) +} + +// reflectType returns an SSA value representing a pointer to typ's +// reflection type descriptor. +func (s *state) reflectType(typ *types.Type) *ssa.Value { + // TODO(mdempsky): Make this Fatalf under Unified IR; frontend needs + // to supply RType expressions. + lsym := reflectdata.TypeLinksym(typ) + return s.entryNewValue1A(ssa.OpAddr, types.NewPtr(types.Types[types.TUINT8]), lsym, s.sb) +} + +func dumpSourcesColumn(writer *ssa.HTMLWriter, fn *ir.Func) { + // Read sources of target function fn. + fname := base.Ctxt.PosTable.Pos(fn.Pos()).Filename() + targetFn, err := readFuncLines(fname, fn.Pos().Line(), fn.Endlineno.Line()) + if err != nil { + writer.Logf("cannot read sources for function %v: %v", fn, err) + } + + // Read sources of inlined functions. + var inlFns []*ssa.FuncLines + for _, fi := range ssaDumpInlined { + elno := fi.Endlineno + fname := base.Ctxt.PosTable.Pos(fi.Pos()).Filename() + fnLines, err := readFuncLines(fname, fi.Pos().Line(), elno.Line()) + if err != nil { + writer.Logf("cannot read sources for inlined function %v: %v", fi, err) + continue + } + inlFns = append(inlFns, fnLines) + } + + sort.Sort(ssa.ByTopo(inlFns)) + if targetFn != nil { + inlFns = append([]*ssa.FuncLines{targetFn}, inlFns...) + } + + writer.WriteSources("sources", inlFns) +} + +func readFuncLines(file string, start, end uint) (*ssa.FuncLines, error) { + f, err := os.Open(os.ExpandEnv(file)) + if err != nil { + return nil, err + } + defer f.Close() + var lines []string + ln := uint(1) + scanner := bufio.NewScanner(f) + for scanner.Scan() && ln <= end { + if ln >= start { + lines = append(lines, scanner.Text()) + } + ln++ + } + return &ssa.FuncLines{Filename: file, StartLineno: start, Lines: lines}, nil +} + +// updateUnsetPredPos propagates the earliest-value position information for b +// towards all of b's predecessors that need a position, and recurs on that +// predecessor if its position is updated. B should have a non-empty position. +func (s *state) updateUnsetPredPos(b *ssa.Block) { + if b.Pos == src.NoXPos { + s.Fatalf("Block %s should have a position", b) + } + bestPos := src.NoXPos + for _, e := range b.Preds { + p := e.Block() + if !p.LackingPos() { + continue + } + if bestPos == src.NoXPos { + bestPos = b.Pos + for _, v := range b.Values { + if v.LackingPos() { + continue + } + if v.Pos != src.NoXPos { + // Assume values are still in roughly textual order; + // TODO: could also seek minimum position? + bestPos = v.Pos + break + } + } + } + p.Pos = bestPos + s.updateUnsetPredPos(p) // We do not expect long chains of these, thus recursion is okay. + } +} + +// Information about each open-coded defer. +type openDeferInfo struct { + // The node representing the call of the defer + n *ir.CallExpr + // If defer call is closure call, the address of the argtmp where the + // closure is stored. + closure *ssa.Value + // The node representing the argtmp where the closure is stored - used for + // function, method, or interface call, to store a closure that panic + // processing can use for this defer. + closureNode *ir.Name +} + +type state struct { + // configuration (arch) information + config *ssa.Config + + // function we're building + f *ssa.Func + + // Node for function + curfn *ir.Func + + // labels in f + labels map[string]*ssaLabel + + // unlabeled break and continue statement tracking + breakTo *ssa.Block // current target for plain break statement + continueTo *ssa.Block // current target for plain continue statement + + // current location where we're interpreting the AST + curBlock *ssa.Block + + // variable assignments in the current block (map from variable symbol to ssa value) + // *Node is the unique identifier (an ONAME Node) for the variable. + // TODO: keep a single varnum map, then make all of these maps slices instead? + vars map[ir.Node]*ssa.Value + + // fwdVars are variables that are used before they are defined in the current block. + // This map exists just to coalesce multiple references into a single FwdRef op. + // *Node is the unique identifier (an ONAME Node) for the variable. + fwdVars map[ir.Node]*ssa.Value + + // all defined variables at the end of each block. Indexed by block ID. + defvars []map[ir.Node]*ssa.Value + + // addresses of PPARAM and PPARAMOUT variables on the stack. + decladdrs map[*ir.Name]*ssa.Value + + // starting values. Memory, stack pointer, and globals pointer + startmem *ssa.Value + sp *ssa.Value + sb *ssa.Value + // value representing address of where deferBits autotmp is stored + deferBitsAddr *ssa.Value + deferBitsTemp *ir.Name + + // line number stack. The current line number is top of stack + line []src.XPos + // the last line number processed; it may have been popped + lastPos src.XPos + + // list of panic calls by function name and line number. + // Used to deduplicate panic calls. + panics map[funcLine]*ssa.Block + + cgoUnsafeArgs bool + hasdefer bool // whether the function contains a defer statement + softFloat bool + hasOpenDefers bool // whether we are doing open-coded defers + checkPtrEnabled bool // whether to insert checkptr instrumentation + + // If doing open-coded defers, list of info about the defer calls in + // scanning order. Hence, at exit we should run these defers in reverse + // order of this list + openDefers []*openDeferInfo + // For open-coded defers, this is the beginning and end blocks of the last + // defer exit code that we have generated so far. We use these to share + // code between exits if the shareDeferExits option (disabled by default) + // is on. + lastDeferExit *ssa.Block // Entry block of last defer exit code we generated + lastDeferFinalBlock *ssa.Block // Final block of last defer exit code we generated + lastDeferCount int // Number of defers encountered at that point + + prevCall *ssa.Value // the previous call; use this to tie results to the call op. +} + +type funcLine struct { + f *obj.LSym + base *src.PosBase + line uint +} + +type ssaLabel struct { + target *ssa.Block // block identified by this label + breakTarget *ssa.Block // block to break to in control flow node identified by this label + continueTarget *ssa.Block // block to continue to in control flow node identified by this label +} + +// label returns the label associated with sym, creating it if necessary. +func (s *state) label(sym *types.Sym) *ssaLabel { + lab := s.labels[sym.Name] + if lab == nil { + lab = new(ssaLabel) + s.labels[sym.Name] = lab + } + return lab +} + +func (s *state) Logf(msg string, args ...interface{}) { s.f.Logf(msg, args...) } +func (s *state) Log() bool { return s.f.Log() } +func (s *state) Fatalf(msg string, args ...interface{}) { + s.f.Frontend().Fatalf(s.peekPos(), msg, args...) +} +func (s *state) Warnl(pos src.XPos, msg string, args ...interface{}) { s.f.Warnl(pos, msg, args...) } +func (s *state) Debug_checknil() bool { return s.f.Frontend().Debug_checknil() } + +func ssaMarker(name string) *ir.Name { + return typecheck.NewName(&types.Sym{Name: name}) +} + +var ( + // marker node for the memory variable + memVar = ssaMarker("mem") + + // marker nodes for temporary variables + ptrVar = ssaMarker("ptr") + lenVar = ssaMarker("len") + capVar = ssaMarker("cap") + typVar = ssaMarker("typ") + okVar = ssaMarker("ok") + deferBitsVar = ssaMarker("deferBits") +) + +// startBlock sets the current block we're generating code in to b. +func (s *state) startBlock(b *ssa.Block) { + if s.curBlock != nil { + s.Fatalf("starting block %v when block %v has not ended", b, s.curBlock) + } + s.curBlock = b + s.vars = map[ir.Node]*ssa.Value{} + for n := range s.fwdVars { + delete(s.fwdVars, n) + } +} + +// endBlock marks the end of generating code for the current block. +// Returns the (former) current block. Returns nil if there is no current +// block, i.e. if no code flows to the current execution point. +func (s *state) endBlock() *ssa.Block { + b := s.curBlock + if b == nil { + return nil + } + for len(s.defvars) <= int(b.ID) { + s.defvars = append(s.defvars, nil) + } + s.defvars[b.ID] = s.vars + s.curBlock = nil + s.vars = nil + if b.LackingPos() { + // Empty plain blocks get the line of their successor (handled after all blocks created), + // except for increment blocks in For statements (handled in ssa conversion of OFOR), + // and for blocks ending in GOTO/BREAK/CONTINUE. + b.Pos = src.NoXPos + } else { + b.Pos = s.lastPos + } + return b +} + +// pushLine pushes a line number on the line number stack. +func (s *state) pushLine(line src.XPos) { + if !line.IsKnown() { + // the frontend may emit node with line number missing, + // use the parent line number in this case. + line = s.peekPos() + if base.Flag.K != 0 { + base.Warn("buildssa: unknown position (line 0)") + } + } else { + s.lastPos = line + } + + s.line = append(s.line, line) +} + +// popLine pops the top of the line number stack. +func (s *state) popLine() { + s.line = s.line[:len(s.line)-1] +} + +// peekPos peeks the top of the line number stack. +func (s *state) peekPos() src.XPos { + return s.line[len(s.line)-1] +} + +// newValue0 adds a new value with no arguments to the current block. +func (s *state) newValue0(op ssa.Op, t *types.Type) *ssa.Value { + return s.curBlock.NewValue0(s.peekPos(), op, t) +} + +// newValue0A adds a new value with no arguments and an aux value to the current block. +func (s *state) newValue0A(op ssa.Op, t *types.Type, aux ssa.Aux) *ssa.Value { + return s.curBlock.NewValue0A(s.peekPos(), op, t, aux) +} + +// newValue0I adds a new value with no arguments and an auxint value to the current block. +func (s *state) newValue0I(op ssa.Op, t *types.Type, auxint int64) *ssa.Value { + return s.curBlock.NewValue0I(s.peekPos(), op, t, auxint) +} + +// newValue1 adds a new value with one argument to the current block. +func (s *state) newValue1(op ssa.Op, t *types.Type, arg *ssa.Value) *ssa.Value { + return s.curBlock.NewValue1(s.peekPos(), op, t, arg) +} + +// newValue1A adds a new value with one argument and an aux value to the current block. +func (s *state) newValue1A(op ssa.Op, t *types.Type, aux ssa.Aux, arg *ssa.Value) *ssa.Value { + return s.curBlock.NewValue1A(s.peekPos(), op, t, aux, arg) +} + +// newValue1Apos adds a new value with one argument and an aux value to the current block. +// isStmt determines whether the created values may be a statement or not +// (i.e., false means never, yes means maybe). +func (s *state) newValue1Apos(op ssa.Op, t *types.Type, aux ssa.Aux, arg *ssa.Value, isStmt bool) *ssa.Value { + if isStmt { + return s.curBlock.NewValue1A(s.peekPos(), op, t, aux, arg) + } + return s.curBlock.NewValue1A(s.peekPos().WithNotStmt(), op, t, aux, arg) +} + +// newValue1I adds a new value with one argument and an auxint value to the current block. +func (s *state) newValue1I(op ssa.Op, t *types.Type, aux int64, arg *ssa.Value) *ssa.Value { + return s.curBlock.NewValue1I(s.peekPos(), op, t, aux, arg) +} + +// newValue2 adds a new value with two arguments to the current block. +func (s *state) newValue2(op ssa.Op, t *types.Type, arg0, arg1 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue2(s.peekPos(), op, t, arg0, arg1) +} + +// newValue2A adds a new value with two arguments and an aux value to the current block. +func (s *state) newValue2A(op ssa.Op, t *types.Type, aux ssa.Aux, arg0, arg1 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue2A(s.peekPos(), op, t, aux, arg0, arg1) +} + +// newValue2Apos adds a new value with two arguments and an aux value to the current block. +// isStmt determines whether the created values may be a statement or not +// (i.e., false means never, yes means maybe). +func (s *state) newValue2Apos(op ssa.Op, t *types.Type, aux ssa.Aux, arg0, arg1 *ssa.Value, isStmt bool) *ssa.Value { + if isStmt { + return s.curBlock.NewValue2A(s.peekPos(), op, t, aux, arg0, arg1) + } + return s.curBlock.NewValue2A(s.peekPos().WithNotStmt(), op, t, aux, arg0, arg1) +} + +// newValue2I adds a new value with two arguments and an auxint value to the current block. +func (s *state) newValue2I(op ssa.Op, t *types.Type, aux int64, arg0, arg1 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue2I(s.peekPos(), op, t, aux, arg0, arg1) +} + +// newValue3 adds a new value with three arguments to the current block. +func (s *state) newValue3(op ssa.Op, t *types.Type, arg0, arg1, arg2 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue3(s.peekPos(), op, t, arg0, arg1, arg2) +} + +// newValue3I adds a new value with three arguments and an auxint value to the current block. +func (s *state) newValue3I(op ssa.Op, t *types.Type, aux int64, arg0, arg1, arg2 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue3I(s.peekPos(), op, t, aux, arg0, arg1, arg2) +} + +// newValue3A adds a new value with three arguments and an aux value to the current block. +func (s *state) newValue3A(op ssa.Op, t *types.Type, aux ssa.Aux, arg0, arg1, arg2 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue3A(s.peekPos(), op, t, aux, arg0, arg1, arg2) +} + +// newValue3Apos adds a new value with three arguments and an aux value to the current block. +// isStmt determines whether the created values may be a statement or not +// (i.e., false means never, yes means maybe). +func (s *state) newValue3Apos(op ssa.Op, t *types.Type, aux ssa.Aux, arg0, arg1, arg2 *ssa.Value, isStmt bool) *ssa.Value { + if isStmt { + return s.curBlock.NewValue3A(s.peekPos(), op, t, aux, arg0, arg1, arg2) + } + return s.curBlock.NewValue3A(s.peekPos().WithNotStmt(), op, t, aux, arg0, arg1, arg2) +} + +// newValue4 adds a new value with four arguments to the current block. +func (s *state) newValue4(op ssa.Op, t *types.Type, arg0, arg1, arg2, arg3 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue4(s.peekPos(), op, t, arg0, arg1, arg2, arg3) +} + +// newValue4I adds a new value with four arguments and an auxint value to the current block. +func (s *state) newValue4I(op ssa.Op, t *types.Type, aux int64, arg0, arg1, arg2, arg3 *ssa.Value) *ssa.Value { + return s.curBlock.NewValue4I(s.peekPos(), op, t, aux, arg0, arg1, arg2, arg3) +} + +func (s *state) entryBlock() *ssa.Block { + b := s.f.Entry + if base.Flag.N > 0 && s.curBlock != nil { + // If optimizations are off, allocate in current block instead. Since with -N + // we're not doing the CSE or tighten passes, putting lots of stuff in the + // entry block leads to O(n^2) entries in the live value map during regalloc. + // See issue 45897. + b = s.curBlock + } + return b +} + +// entryNewValue0 adds a new value with no arguments to the entry block. +func (s *state) entryNewValue0(op ssa.Op, t *types.Type) *ssa.Value { + return s.entryBlock().NewValue0(src.NoXPos, op, t) +} + +// entryNewValue0A adds a new value with no arguments and an aux value to the entry block. +func (s *state) entryNewValue0A(op ssa.Op, t *types.Type, aux ssa.Aux) *ssa.Value { + return s.entryBlock().NewValue0A(src.NoXPos, op, t, aux) +} + +// entryNewValue1 adds a new value with one argument to the entry block. +func (s *state) entryNewValue1(op ssa.Op, t *types.Type, arg *ssa.Value) *ssa.Value { + return s.entryBlock().NewValue1(src.NoXPos, op, t, arg) +} + +// entryNewValue1I adds a new value with one argument and an auxint value to the entry block. +func (s *state) entryNewValue1I(op ssa.Op, t *types.Type, auxint int64, arg *ssa.Value) *ssa.Value { + return s.entryBlock().NewValue1I(src.NoXPos, op, t, auxint, arg) +} + +// entryNewValue1A adds a new value with one argument and an aux value to the entry block. +func (s *state) entryNewValue1A(op ssa.Op, t *types.Type, aux ssa.Aux, arg *ssa.Value) *ssa.Value { + return s.entryBlock().NewValue1A(src.NoXPos, op, t, aux, arg) +} + +// entryNewValue2 adds a new value with two arguments to the entry block. +func (s *state) entryNewValue2(op ssa.Op, t *types.Type, arg0, arg1 *ssa.Value) *ssa.Value { + return s.entryBlock().NewValue2(src.NoXPos, op, t, arg0, arg1) +} + +// entryNewValue2A adds a new value with two arguments and an aux value to the entry block. +func (s *state) entryNewValue2A(op ssa.Op, t *types.Type, aux ssa.Aux, arg0, arg1 *ssa.Value) *ssa.Value { + return s.entryBlock().NewValue2A(src.NoXPos, op, t, aux, arg0, arg1) +} + +// const* routines add a new const value to the entry block. +func (s *state) constSlice(t *types.Type) *ssa.Value { + return s.f.ConstSlice(t) +} +func (s *state) constInterface(t *types.Type) *ssa.Value { + return s.f.ConstInterface(t) +} +func (s *state) constNil(t *types.Type) *ssa.Value { return s.f.ConstNil(t) } +func (s *state) constEmptyString(t *types.Type) *ssa.Value { + return s.f.ConstEmptyString(t) +} +func (s *state) constBool(c bool) *ssa.Value { + return s.f.ConstBool(types.Types[types.TBOOL], c) +} +func (s *state) constInt8(t *types.Type, c int8) *ssa.Value { + return s.f.ConstInt8(t, c) +} +func (s *state) constInt16(t *types.Type, c int16) *ssa.Value { + return s.f.ConstInt16(t, c) +} +func (s *state) constInt32(t *types.Type, c int32) *ssa.Value { + return s.f.ConstInt32(t, c) +} +func (s *state) constInt64(t *types.Type, c int64) *ssa.Value { + return s.f.ConstInt64(t, c) +} +func (s *state) constFloat32(t *types.Type, c float64) *ssa.Value { + return s.f.ConstFloat32(t, c) +} +func (s *state) constFloat64(t *types.Type, c float64) *ssa.Value { + return s.f.ConstFloat64(t, c) +} +func (s *state) constInt(t *types.Type, c int64) *ssa.Value { + if s.config.PtrSize == 8 { + return s.constInt64(t, c) + } + if int64(int32(c)) != c { + s.Fatalf("integer constant too big %d", c) + } + return s.constInt32(t, int32(c)) +} +func (s *state) constOffPtrSP(t *types.Type, c int64) *ssa.Value { + return s.f.ConstOffPtrSP(t, c, s.sp) +} + +// newValueOrSfCall* are wrappers around newValue*, which may create a call to a +// soft-float runtime function instead (when emitting soft-float code). +func (s *state) newValueOrSfCall1(op ssa.Op, t *types.Type, arg *ssa.Value) *ssa.Value { + if s.softFloat { + if c, ok := s.sfcall(op, arg); ok { + return c + } + } + return s.newValue1(op, t, arg) +} +func (s *state) newValueOrSfCall2(op ssa.Op, t *types.Type, arg0, arg1 *ssa.Value) *ssa.Value { + if s.softFloat { + if c, ok := s.sfcall(op, arg0, arg1); ok { + return c + } + } + return s.newValue2(op, t, arg0, arg1) +} + +type instrumentKind uint8 + +const ( + instrumentRead = iota + instrumentWrite + instrumentMove +) + +func (s *state) instrument(t *types.Type, addr *ssa.Value, kind instrumentKind) { + s.instrument2(t, addr, nil, kind) +} + +// instrumentFields instruments a read/write operation on addr. +// If it is instrumenting for MSAN or ASAN and t is a struct type, it instruments +// operation for each field, instead of for the whole struct. +func (s *state) instrumentFields(t *types.Type, addr *ssa.Value, kind instrumentKind) { + if !(base.Flag.MSan || base.Flag.ASan) || !t.IsStruct() { + s.instrument(t, addr, kind) + return + } + for _, f := range t.Fields().Slice() { + if f.Sym.IsBlank() { + continue + } + offptr := s.newValue1I(ssa.OpOffPtr, types.NewPtr(f.Type), f.Offset, addr) + s.instrumentFields(f.Type, offptr, kind) + } +} + +func (s *state) instrumentMove(t *types.Type, dst, src *ssa.Value) { + if base.Flag.MSan { + s.instrument2(t, dst, src, instrumentMove) + } else { + s.instrument(t, src, instrumentRead) + s.instrument(t, dst, instrumentWrite) + } +} + +func (s *state) instrument2(t *types.Type, addr, addr2 *ssa.Value, kind instrumentKind) { + if !s.curfn.InstrumentBody() { + return + } + + w := t.Size() + if w == 0 { + return // can't race on zero-sized things + } + + if ssa.IsSanitizerSafeAddr(addr) { + return + } + + var fn *obj.LSym + needWidth := false + + if addr2 != nil && kind != instrumentMove { + panic("instrument2: non-nil addr2 for non-move instrumentation") + } + + if base.Flag.MSan { + switch kind { + case instrumentRead: + fn = ir.Syms.Msanread + case instrumentWrite: + fn = ir.Syms.Msanwrite + case instrumentMove: + fn = ir.Syms.Msanmove + default: + panic("unreachable") + } + needWidth = true + } else if base.Flag.Race && t.NumComponents(types.CountBlankFields) > 1 { + // for composite objects we have to write every address + // because a write might happen to any subobject. + // composites with only one element don't have subobjects, though. + switch kind { + case instrumentRead: + fn = ir.Syms.Racereadrange + case instrumentWrite: + fn = ir.Syms.Racewriterange + default: + panic("unreachable") + } + needWidth = true + } else if base.Flag.Race { + // for non-composite objects we can write just the start + // address, as any write must write the first byte. + switch kind { + case instrumentRead: + fn = ir.Syms.Raceread + case instrumentWrite: + fn = ir.Syms.Racewrite + default: + panic("unreachable") + } + } else if base.Flag.ASan { + switch kind { + case instrumentRead: + fn = ir.Syms.Asanread + case instrumentWrite: + fn = ir.Syms.Asanwrite + default: + panic("unreachable") + } + needWidth = true + } else { + panic("unreachable") + } + + args := []*ssa.Value{addr} + if addr2 != nil { + args = append(args, addr2) + } + if needWidth { + args = append(args, s.constInt(types.Types[types.TUINTPTR], w)) + } + s.rtcall(fn, true, nil, args...) +} + +func (s *state) load(t *types.Type, src *ssa.Value) *ssa.Value { + s.instrumentFields(t, src, instrumentRead) + return s.rawLoad(t, src) +} + +func (s *state) rawLoad(t *types.Type, src *ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpLoad, t, src, s.mem()) +} + +func (s *state) store(t *types.Type, dst, val *ssa.Value) { + s.vars[memVar] = s.newValue3A(ssa.OpStore, types.TypeMem, t, dst, val, s.mem()) +} + +func (s *state) zero(t *types.Type, dst *ssa.Value) { + s.instrument(t, dst, instrumentWrite) + store := s.newValue2I(ssa.OpZero, types.TypeMem, t.Size(), dst, s.mem()) + store.Aux = t + s.vars[memVar] = store +} + +func (s *state) move(t *types.Type, dst, src *ssa.Value) { + s.moveWhichMayOverlap(t, dst, src, false) +} +func (s *state) moveWhichMayOverlap(t *types.Type, dst, src *ssa.Value, mayOverlap bool) { + s.instrumentMove(t, dst, src) + if mayOverlap && t.IsArray() && t.NumElem() > 1 && !ssa.IsInlinableMemmove(dst, src, t.Size(), s.f.Config) { + // Normally, when moving Go values of type T from one location to another, + // we don't need to worry about partial overlaps. The two Ts must either be + // in disjoint (nonoverlapping) memory or in exactly the same location. + // There are 2 cases where this isn't true: + // 1) Using unsafe you can arrange partial overlaps. + // 2) Since Go 1.17, you can use a cast from a slice to a ptr-to-array. + // https://go.dev/ref/spec#Conversions_from_slice_to_array_pointer + // This feature can be used to construct partial overlaps of array types. + // var a [3]int + // p := (*[2]int)(a[:]) + // q := (*[2]int)(a[1:]) + // *p = *q + // We don't care about solving 1. Or at least, we haven't historically + // and no one has complained. + // For 2, we need to ensure that if there might be partial overlap, + // then we can't use OpMove; we must use memmove instead. + // (memmove handles partial overlap by copying in the correct + // direction. OpMove does not.) + // + // Note that we have to be careful here not to introduce a call when + // we're marshaling arguments to a call or unmarshaling results from a call. + // Cases where this is happening must pass mayOverlap to false. + // (Currently this only happens when unmarshaling results of a call.) + if t.HasPointers() { + s.rtcall(ir.Syms.Typedmemmove, true, nil, s.reflectType(t), dst, src) + // We would have otherwise implemented this move with straightline code, + // including a write barrier. Pretend we issue a write barrier here, + // so that the write barrier tests work. (Otherwise they'd need to know + // the details of IsInlineableMemmove.) + s.curfn.SetWBPos(s.peekPos()) + } else { + s.rtcall(ir.Syms.Memmove, true, nil, dst, src, s.constInt(types.Types[types.TUINTPTR], t.Size())) + } + ssa.LogLargeCopy(s.f.Name, s.peekPos(), t.Size()) + return + } + store := s.newValue3I(ssa.OpMove, types.TypeMem, t.Size(), dst, src, s.mem()) + store.Aux = t + s.vars[memVar] = store +} + +// stmtList converts the statement list n to SSA and adds it to s. +func (s *state) stmtList(l ir.Nodes) { + for _, n := range l { + s.stmt(n) + } +} + +// stmt converts the statement n to SSA and adds it to s. +func (s *state) stmt(n ir.Node) { + s.pushLine(n.Pos()) + defer s.popLine() + + // If s.curBlock is nil, and n isn't a label (which might have an associated goto somewhere), + // then this code is dead. Stop here. + if s.curBlock == nil && n.Op() != ir.OLABEL { + return + } + + s.stmtList(n.Init()) + switch n.Op() { + + case ir.OBLOCK: + n := n.(*ir.BlockStmt) + s.stmtList(n.List) + + // No-ops + case ir.ODCLCONST, ir.ODCLTYPE, ir.OFALL: + + // Expression statements + case ir.OCALLFUNC: + n := n.(*ir.CallExpr) + if ir.IsIntrinsicCall(n) { + s.intrinsicCall(n) + return + } + fallthrough + + case ir.OCALLINTER: + n := n.(*ir.CallExpr) + s.callResult(n, callNormal) + if n.Op() == ir.OCALLFUNC && n.X.Op() == ir.ONAME && n.X.(*ir.Name).Class == ir.PFUNC { + if fn := n.X.Sym().Name; base.Flag.CompilingRuntime && fn == "throw" || + n.X.Sym().Pkg == ir.Pkgs.Runtime && (fn == "throwinit" || fn == "gopanic" || fn == "panicwrap" || fn == "block" || fn == "panicmakeslicelen" || fn == "panicmakeslicecap" || fn == "panicunsafeslicelen" || fn == "panicunsafeslicenilptr" || fn == "panicunsafestringlen" || fn == "panicunsafestringnilptr") { + m := s.mem() + b := s.endBlock() + b.Kind = ssa.BlockExit + b.SetControl(m) + // TODO: never rewrite OPANIC to OCALLFUNC in the + // first place. Need to wait until all backends + // go through SSA. + } + } + case ir.ODEFER: + n := n.(*ir.GoDeferStmt) + if base.Debug.Defer > 0 { + var defertype string + if s.hasOpenDefers { + defertype = "open-coded" + } else if n.Esc() == ir.EscNever { + defertype = "stack-allocated" + } else { + defertype = "heap-allocated" + } + base.WarnfAt(n.Pos(), "%s defer", defertype) + } + if s.hasOpenDefers { + s.openDeferRecord(n.Call.(*ir.CallExpr)) + } else { + d := callDefer + if n.Esc() == ir.EscNever { + d = callDeferStack + } + s.callResult(n.Call.(*ir.CallExpr), d) + } + case ir.OGO: + n := n.(*ir.GoDeferStmt) + s.callResult(n.Call.(*ir.CallExpr), callGo) + + case ir.OAS2DOTTYPE: + n := n.(*ir.AssignListStmt) + var res, resok *ssa.Value + if n.Rhs[0].Op() == ir.ODOTTYPE2 { + res, resok = s.dottype(n.Rhs[0].(*ir.TypeAssertExpr), true) + } else { + res, resok = s.dynamicDottype(n.Rhs[0].(*ir.DynamicTypeAssertExpr), true) + } + deref := false + if !TypeOK(n.Rhs[0].Type()) { + if res.Op != ssa.OpLoad { + s.Fatalf("dottype of non-load") + } + mem := s.mem() + if res.Args[1] != mem { + s.Fatalf("memory no longer live from 2-result dottype load") + } + deref = true + res = res.Args[0] + } + s.assign(n.Lhs[0], res, deref, 0) + s.assign(n.Lhs[1], resok, false, 0) + return + + case ir.OAS2FUNC: + // We come here only when it is an intrinsic call returning two values. + n := n.(*ir.AssignListStmt) + call := n.Rhs[0].(*ir.CallExpr) + if !ir.IsIntrinsicCall(call) { + s.Fatalf("non-intrinsic AS2FUNC not expanded %v", call) + } + v := s.intrinsicCall(call) + v1 := s.newValue1(ssa.OpSelect0, n.Lhs[0].Type(), v) + v2 := s.newValue1(ssa.OpSelect1, n.Lhs[1].Type(), v) + s.assign(n.Lhs[0], v1, false, 0) + s.assign(n.Lhs[1], v2, false, 0) + return + + case ir.ODCL: + n := n.(*ir.Decl) + if v := n.X; v.Esc() == ir.EscHeap { + s.newHeapaddr(v) + } + + case ir.OLABEL: + n := n.(*ir.LabelStmt) + sym := n.Label + if sym.IsBlank() { + // Nothing to do because the label isn't targetable. See issue 52278. + break + } + lab := s.label(sym) + + // The label might already have a target block via a goto. + if lab.target == nil { + lab.target = s.f.NewBlock(ssa.BlockPlain) + } + + // Go to that label. + // (We pretend "label:" is preceded by "goto label", unless the predecessor is unreachable.) + if s.curBlock != nil { + b := s.endBlock() + b.AddEdgeTo(lab.target) + } + s.startBlock(lab.target) + + case ir.OGOTO: + n := n.(*ir.BranchStmt) + sym := n.Label + + lab := s.label(sym) + if lab.target == nil { + lab.target = s.f.NewBlock(ssa.BlockPlain) + } + + b := s.endBlock() + b.Pos = s.lastPos.WithIsStmt() // Do this even if b is an empty block. + b.AddEdgeTo(lab.target) + + case ir.OAS: + n := n.(*ir.AssignStmt) + if n.X == n.Y && n.X.Op() == ir.ONAME { + // An x=x assignment. No point in doing anything + // here. In addition, skipping this assignment + // prevents generating: + // VARDEF x + // COPY x -> x + // which is bad because x is incorrectly considered + // dead before the vardef. See issue #14904. + return + } + + // mayOverlap keeps track of whether the LHS and RHS might + // refer to partially overlapping memory. Partial overlapping can + // only happen for arrays, see the comment in moveWhichMayOverlap. + // + // If both sides of the assignment are not dereferences, then partial + // overlap can't happen. Partial overlap can only occur only when the + // arrays referenced are strictly smaller parts of the same base array. + // If one side of the assignment is a full array, then partial overlap + // can't happen. (The arrays are either disjoint or identical.) + mayOverlap := n.X.Op() == ir.ODEREF && (n.Y != nil && n.Y.Op() == ir.ODEREF) + if n.Y != nil && n.Y.Op() == ir.ODEREF { + p := n.Y.(*ir.StarExpr).X + for p.Op() == ir.OCONVNOP { + p = p.(*ir.ConvExpr).X + } + if p.Op() == ir.OSPTR && p.(*ir.UnaryExpr).X.Type().IsString() { + // Pointer fields of strings point to unmodifiable memory. + // That memory can't overlap with the memory being written. + mayOverlap = false + } + } + + // Evaluate RHS. + rhs := n.Y + if rhs != nil { + switch rhs.Op() { + case ir.OSTRUCTLIT, ir.OARRAYLIT, ir.OSLICELIT: + // All literals with nonzero fields have already been + // rewritten during walk. Any that remain are just T{} + // or equivalents. Use the zero value. + if !ir.IsZero(rhs) { + s.Fatalf("literal with nonzero value in SSA: %v", rhs) + } + rhs = nil + case ir.OAPPEND: + rhs := rhs.(*ir.CallExpr) + // Check whether we're writing the result of an append back to the same slice. + // If so, we handle it specially to avoid write barriers on the fast + // (non-growth) path. + if !ir.SameSafeExpr(n.X, rhs.Args[0]) || base.Flag.N != 0 { + break + } + // If the slice can be SSA'd, it'll be on the stack, + // so there will be no write barriers, + // so there's no need to attempt to prevent them. + if s.canSSA(n.X) { + if base.Debug.Append > 0 { // replicating old diagnostic message + base.WarnfAt(n.Pos(), "append: len-only update (in local slice)") + } + break + } + if base.Debug.Append > 0 { + base.WarnfAt(n.Pos(), "append: len-only update") + } + s.append(rhs, true) + return + } + } + + if ir.IsBlank(n.X) { + // _ = rhs + // Just evaluate rhs for side-effects. + if rhs != nil { + s.expr(rhs) + } + return + } + + var t *types.Type + if n.Y != nil { + t = n.Y.Type() + } else { + t = n.X.Type() + } + + var r *ssa.Value + deref := !TypeOK(t) + if deref { + if rhs == nil { + r = nil // Signal assign to use OpZero. + } else { + r = s.addr(rhs) + } + } else { + if rhs == nil { + r = s.zeroVal(t) + } else { + r = s.expr(rhs) + } + } + + var skip skipMask + if rhs != nil && (rhs.Op() == ir.OSLICE || rhs.Op() == ir.OSLICE3 || rhs.Op() == ir.OSLICESTR) && ir.SameSafeExpr(rhs.(*ir.SliceExpr).X, n.X) { + // We're assigning a slicing operation back to its source. + // Don't write back fields we aren't changing. See issue #14855. + rhs := rhs.(*ir.SliceExpr) + i, j, k := rhs.Low, rhs.High, rhs.Max + if i != nil && (i.Op() == ir.OLITERAL && i.Val().Kind() == constant.Int && ir.Int64Val(i) == 0) { + // [0:...] is the same as [:...] + i = nil + } + // TODO: detect defaults for len/cap also. + // Currently doesn't really work because (*p)[:len(*p)] appears here as: + // tmp = len(*p) + // (*p)[:tmp] + // if j != nil && (j.Op == OLEN && SameSafeExpr(j.Left, n.Left)) { + // j = nil + // } + // if k != nil && (k.Op == OCAP && SameSafeExpr(k.Left, n.Left)) { + // k = nil + // } + if i == nil { + skip |= skipPtr + if j == nil { + skip |= skipLen + } + if k == nil { + skip |= skipCap + } + } + } + + s.assignWhichMayOverlap(n.X, r, deref, skip, mayOverlap) + + case ir.OIF: + n := n.(*ir.IfStmt) + if ir.IsConst(n.Cond, constant.Bool) { + s.stmtList(n.Cond.Init()) + if ir.BoolVal(n.Cond) { + s.stmtList(n.Body) + } else { + s.stmtList(n.Else) + } + break + } + + bEnd := s.f.NewBlock(ssa.BlockPlain) + var likely int8 + if n.Likely { + likely = 1 + } + var bThen *ssa.Block + if len(n.Body) != 0 { + bThen = s.f.NewBlock(ssa.BlockPlain) + } else { + bThen = bEnd + } + var bElse *ssa.Block + if len(n.Else) != 0 { + bElse = s.f.NewBlock(ssa.BlockPlain) + } else { + bElse = bEnd + } + s.condBranch(n.Cond, bThen, bElse, likely) + + if len(n.Body) != 0 { + s.startBlock(bThen) + s.stmtList(n.Body) + if b := s.endBlock(); b != nil { + b.AddEdgeTo(bEnd) + } + } + if len(n.Else) != 0 { + s.startBlock(bElse) + s.stmtList(n.Else) + if b := s.endBlock(); b != nil { + b.AddEdgeTo(bEnd) + } + } + s.startBlock(bEnd) + + case ir.ORETURN: + n := n.(*ir.ReturnStmt) + s.stmtList(n.Results) + b := s.exit() + b.Pos = s.lastPos.WithIsStmt() + + case ir.OTAILCALL: + n := n.(*ir.TailCallStmt) + s.callResult(n.Call, callTail) + call := s.mem() + b := s.endBlock() + b.Kind = ssa.BlockRetJmp // could use BlockExit. BlockRetJmp is mostly for clarity. + b.SetControl(call) + + case ir.OCONTINUE, ir.OBREAK: + n := n.(*ir.BranchStmt) + var to *ssa.Block + if n.Label == nil { + // plain break/continue + switch n.Op() { + case ir.OCONTINUE: + to = s.continueTo + case ir.OBREAK: + to = s.breakTo + } + } else { + // labeled break/continue; look up the target + sym := n.Label + lab := s.label(sym) + switch n.Op() { + case ir.OCONTINUE: + to = lab.continueTarget + case ir.OBREAK: + to = lab.breakTarget + } + } + + b := s.endBlock() + b.Pos = s.lastPos.WithIsStmt() // Do this even if b is an empty block. + b.AddEdgeTo(to) + + case ir.OFOR: + // OFOR: for Ninit; Left; Right { Nbody } + // cond (Left); body (Nbody); incr (Right) + n := n.(*ir.ForStmt) + base.Assert(!n.DistinctVars) // Should all be rewritten before escape analysis + bCond := s.f.NewBlock(ssa.BlockPlain) + bBody := s.f.NewBlock(ssa.BlockPlain) + bIncr := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + + // ensure empty for loops have correct position; issue #30167 + bBody.Pos = n.Pos() + + // first, jump to condition test + b := s.endBlock() + b.AddEdgeTo(bCond) + + // generate code to test condition + s.startBlock(bCond) + if n.Cond != nil { + s.condBranch(n.Cond, bBody, bEnd, 1) + } else { + b := s.endBlock() + b.Kind = ssa.BlockPlain + b.AddEdgeTo(bBody) + } + + // set up for continue/break in body + prevContinue := s.continueTo + prevBreak := s.breakTo + s.continueTo = bIncr + s.breakTo = bEnd + var lab *ssaLabel + if sym := n.Label; sym != nil { + // labeled for loop + lab = s.label(sym) + lab.continueTarget = bIncr + lab.breakTarget = bEnd + } + + // generate body + s.startBlock(bBody) + s.stmtList(n.Body) + + // tear down continue/break + s.continueTo = prevContinue + s.breakTo = prevBreak + if lab != nil { + lab.continueTarget = nil + lab.breakTarget = nil + } + + // done with body, goto incr + if b := s.endBlock(); b != nil { + b.AddEdgeTo(bIncr) + } + + // generate incr + s.startBlock(bIncr) + if n.Post != nil { + s.stmt(n.Post) + } + if b := s.endBlock(); b != nil { + b.AddEdgeTo(bCond) + // It can happen that bIncr ends in a block containing only VARKILL, + // and that muddles the debugging experience. + if b.Pos == src.NoXPos { + b.Pos = bCond.Pos + } + } + + s.startBlock(bEnd) + + case ir.OSWITCH, ir.OSELECT: + // These have been mostly rewritten by the front end into their Nbody fields. + // Our main task is to correctly hook up any break statements. + bEnd := s.f.NewBlock(ssa.BlockPlain) + + prevBreak := s.breakTo + s.breakTo = bEnd + var sym *types.Sym + var body ir.Nodes + if n.Op() == ir.OSWITCH { + n := n.(*ir.SwitchStmt) + sym = n.Label + body = n.Compiled + } else { + n := n.(*ir.SelectStmt) + sym = n.Label + body = n.Compiled + } + + var lab *ssaLabel + if sym != nil { + // labeled + lab = s.label(sym) + lab.breakTarget = bEnd + } + + // generate body code + s.stmtList(body) + + s.breakTo = prevBreak + if lab != nil { + lab.breakTarget = nil + } + + // walk adds explicit OBREAK nodes to the end of all reachable code paths. + // If we still have a current block here, then mark it unreachable. + if s.curBlock != nil { + m := s.mem() + b := s.endBlock() + b.Kind = ssa.BlockExit + b.SetControl(m) + } + s.startBlock(bEnd) + + case ir.OJUMPTABLE: + n := n.(*ir.JumpTableStmt) + + // Make blocks we'll need. + jt := s.f.NewBlock(ssa.BlockJumpTable) + bEnd := s.f.NewBlock(ssa.BlockPlain) + + // The only thing that needs evaluating is the index we're looking up. + idx := s.expr(n.Idx) + unsigned := idx.Type.IsUnsigned() + + // Extend so we can do everything in uintptr arithmetic. + t := types.Types[types.TUINTPTR] + idx = s.conv(nil, idx, idx.Type, t) + + // The ending condition for the current block decides whether we'll use + // the jump table at all. + // We check that min <= idx <= max and jump around the jump table + // if that test fails. + // We implement min <= idx <= max with 0 <= idx-min <= max-min, because + // we'll need idx-min anyway as the control value for the jump table. + var min, max uint64 + if unsigned { + min, _ = constant.Uint64Val(n.Cases[0]) + max, _ = constant.Uint64Val(n.Cases[len(n.Cases)-1]) + } else { + mn, _ := constant.Int64Val(n.Cases[0]) + mx, _ := constant.Int64Val(n.Cases[len(n.Cases)-1]) + min = uint64(mn) + max = uint64(mx) + } + // Compare idx-min with max-min, to see if we can use the jump table. + idx = s.newValue2(s.ssaOp(ir.OSUB, t), t, idx, s.uintptrConstant(min)) + width := s.uintptrConstant(max - min) + cmp := s.newValue2(s.ssaOp(ir.OLE, t), types.Types[types.TBOOL], idx, width) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.AddEdgeTo(jt) // in range - use jump table + b.AddEdgeTo(bEnd) // out of range - no case in the jump table will trigger + b.Likely = ssa.BranchLikely // TODO: assumes missing the table entirely is unlikely. True? + + // Build jump table block. + s.startBlock(jt) + jt.Pos = n.Pos() + if base.Flag.Cfg.SpectreIndex { + idx = s.newValue2(ssa.OpSpectreSliceIndex, t, idx, width) + } + jt.SetControl(idx) + + // Figure out where we should go for each index in the table. + table := make([]*ssa.Block, max-min+1) + for i := range table { + table[i] = bEnd // default target + } + for i := range n.Targets { + c := n.Cases[i] + lab := s.label(n.Targets[i]) + if lab.target == nil { + lab.target = s.f.NewBlock(ssa.BlockPlain) + } + var val uint64 + if unsigned { + val, _ = constant.Uint64Val(c) + } else { + vl, _ := constant.Int64Val(c) + val = uint64(vl) + } + // Overwrite the default target. + table[val-min] = lab.target + } + for _, t := range table { + jt.AddEdgeTo(t) + } + s.endBlock() + + s.startBlock(bEnd) + + case ir.OCHECKNIL: + n := n.(*ir.UnaryExpr) + p := s.expr(n.X) + _ = s.nilCheck(p) + // TODO: check that throwing away the nilcheck result is ok. + + case ir.OINLMARK: + n := n.(*ir.InlineMarkStmt) + s.newValue1I(ssa.OpInlMark, types.TypeVoid, n.Index, s.mem()) + + default: + s.Fatalf("unhandled stmt %v", n.Op()) + } +} + +// If true, share as many open-coded defer exits as possible (with the downside of +// worse line-number information) +const shareDeferExits = false + +// exit processes any code that needs to be generated just before returning. +// It returns a BlockRet block that ends the control flow. Its control value +// will be set to the final memory state. +func (s *state) exit() *ssa.Block { + if s.hasdefer { + if s.hasOpenDefers { + if shareDeferExits && s.lastDeferExit != nil && len(s.openDefers) == s.lastDeferCount { + if s.curBlock.Kind != ssa.BlockPlain { + panic("Block for an exit should be BlockPlain") + } + s.curBlock.AddEdgeTo(s.lastDeferExit) + s.endBlock() + return s.lastDeferFinalBlock + } + s.openDeferExit() + } else { + s.rtcall(ir.Syms.Deferreturn, true, nil) + } + } + + var b *ssa.Block + var m *ssa.Value + // Do actual return. + // These currently turn into self-copies (in many cases). + resultFields := s.curfn.Type().Results().FieldSlice() + results := make([]*ssa.Value, len(resultFields)+1, len(resultFields)+1) + m = s.newValue0(ssa.OpMakeResult, s.f.OwnAux.LateExpansionResultType()) + // Store SSAable and heap-escaped PPARAMOUT variables back to stack locations. + for i, f := range resultFields { + n := f.Nname.(*ir.Name) + if s.canSSA(n) { // result is in some SSA variable + if !n.IsOutputParamInRegisters() && n.Type().HasPointers() { + // We are about to store to the result slot. + s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, n, s.mem()) + } + results[i] = s.variable(n, n.Type()) + } else if !n.OnStack() { // result is actually heap allocated + // We are about to copy the in-heap result to the result slot. + if n.Type().HasPointers() { + s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, n, s.mem()) + } + ha := s.expr(n.Heapaddr) + s.instrumentFields(n.Type(), ha, instrumentRead) + results[i] = s.newValue2(ssa.OpDereference, n.Type(), ha, s.mem()) + } else { // result is not SSA-able; not escaped, so not on heap, but too large for SSA. + // Before register ABI this ought to be a self-move, home=dest, + // With register ABI, it's still a self-move if parameter is on stack (i.e., too big or overflowed) + // No VarDef, as the result slot is already holding live value. + results[i] = s.newValue2(ssa.OpDereference, n.Type(), s.addr(n), s.mem()) + } + } + + // Run exit code. Today, this is just racefuncexit, in -race mode. + // TODO(register args) this seems risky here with a register-ABI, but not clear it is right to do it earlier either. + // Spills in register allocation might just fix it. + s.stmtList(s.curfn.Exit) + + results[len(results)-1] = s.mem() + m.AddArgs(results...) + + b = s.endBlock() + b.Kind = ssa.BlockRet + b.SetControl(m) + if s.hasdefer && s.hasOpenDefers { + s.lastDeferFinalBlock = b + } + return b +} + +type opAndType struct { + op ir.Op + etype types.Kind +} + +var opToSSA = map[opAndType]ssa.Op{ + {ir.OADD, types.TINT8}: ssa.OpAdd8, + {ir.OADD, types.TUINT8}: ssa.OpAdd8, + {ir.OADD, types.TINT16}: ssa.OpAdd16, + {ir.OADD, types.TUINT16}: ssa.OpAdd16, + {ir.OADD, types.TINT32}: ssa.OpAdd32, + {ir.OADD, types.TUINT32}: ssa.OpAdd32, + {ir.OADD, types.TINT64}: ssa.OpAdd64, + {ir.OADD, types.TUINT64}: ssa.OpAdd64, + {ir.OADD, types.TFLOAT32}: ssa.OpAdd32F, + {ir.OADD, types.TFLOAT64}: ssa.OpAdd64F, + + {ir.OSUB, types.TINT8}: ssa.OpSub8, + {ir.OSUB, types.TUINT8}: ssa.OpSub8, + {ir.OSUB, types.TINT16}: ssa.OpSub16, + {ir.OSUB, types.TUINT16}: ssa.OpSub16, + {ir.OSUB, types.TINT32}: ssa.OpSub32, + {ir.OSUB, types.TUINT32}: ssa.OpSub32, + {ir.OSUB, types.TINT64}: ssa.OpSub64, + {ir.OSUB, types.TUINT64}: ssa.OpSub64, + {ir.OSUB, types.TFLOAT32}: ssa.OpSub32F, + {ir.OSUB, types.TFLOAT64}: ssa.OpSub64F, + + {ir.ONOT, types.TBOOL}: ssa.OpNot, + + {ir.ONEG, types.TINT8}: ssa.OpNeg8, + {ir.ONEG, types.TUINT8}: ssa.OpNeg8, + {ir.ONEG, types.TINT16}: ssa.OpNeg16, + {ir.ONEG, types.TUINT16}: ssa.OpNeg16, + {ir.ONEG, types.TINT32}: ssa.OpNeg32, + {ir.ONEG, types.TUINT32}: ssa.OpNeg32, + {ir.ONEG, types.TINT64}: ssa.OpNeg64, + {ir.ONEG, types.TUINT64}: ssa.OpNeg64, + {ir.ONEG, types.TFLOAT32}: ssa.OpNeg32F, + {ir.ONEG, types.TFLOAT64}: ssa.OpNeg64F, + + {ir.OBITNOT, types.TINT8}: ssa.OpCom8, + {ir.OBITNOT, types.TUINT8}: ssa.OpCom8, + {ir.OBITNOT, types.TINT16}: ssa.OpCom16, + {ir.OBITNOT, types.TUINT16}: ssa.OpCom16, + {ir.OBITNOT, types.TINT32}: ssa.OpCom32, + {ir.OBITNOT, types.TUINT32}: ssa.OpCom32, + {ir.OBITNOT, types.TINT64}: ssa.OpCom64, + {ir.OBITNOT, types.TUINT64}: ssa.OpCom64, + + {ir.OIMAG, types.TCOMPLEX64}: ssa.OpComplexImag, + {ir.OIMAG, types.TCOMPLEX128}: ssa.OpComplexImag, + {ir.OREAL, types.TCOMPLEX64}: ssa.OpComplexReal, + {ir.OREAL, types.TCOMPLEX128}: ssa.OpComplexReal, + + {ir.OMUL, types.TINT8}: ssa.OpMul8, + {ir.OMUL, types.TUINT8}: ssa.OpMul8, + {ir.OMUL, types.TINT16}: ssa.OpMul16, + {ir.OMUL, types.TUINT16}: ssa.OpMul16, + {ir.OMUL, types.TINT32}: ssa.OpMul32, + {ir.OMUL, types.TUINT32}: ssa.OpMul32, + {ir.OMUL, types.TINT64}: ssa.OpMul64, + {ir.OMUL, types.TUINT64}: ssa.OpMul64, + {ir.OMUL, types.TFLOAT32}: ssa.OpMul32F, + {ir.OMUL, types.TFLOAT64}: ssa.OpMul64F, + + {ir.ODIV, types.TFLOAT32}: ssa.OpDiv32F, + {ir.ODIV, types.TFLOAT64}: ssa.OpDiv64F, + + {ir.ODIV, types.TINT8}: ssa.OpDiv8, + {ir.ODIV, types.TUINT8}: ssa.OpDiv8u, + {ir.ODIV, types.TINT16}: ssa.OpDiv16, + {ir.ODIV, types.TUINT16}: ssa.OpDiv16u, + {ir.ODIV, types.TINT32}: ssa.OpDiv32, + {ir.ODIV, types.TUINT32}: ssa.OpDiv32u, + {ir.ODIV, types.TINT64}: ssa.OpDiv64, + {ir.ODIV, types.TUINT64}: ssa.OpDiv64u, + + {ir.OMOD, types.TINT8}: ssa.OpMod8, + {ir.OMOD, types.TUINT8}: ssa.OpMod8u, + {ir.OMOD, types.TINT16}: ssa.OpMod16, + {ir.OMOD, types.TUINT16}: ssa.OpMod16u, + {ir.OMOD, types.TINT32}: ssa.OpMod32, + {ir.OMOD, types.TUINT32}: ssa.OpMod32u, + {ir.OMOD, types.TINT64}: ssa.OpMod64, + {ir.OMOD, types.TUINT64}: ssa.OpMod64u, + + {ir.OAND, types.TINT8}: ssa.OpAnd8, + {ir.OAND, types.TUINT8}: ssa.OpAnd8, + {ir.OAND, types.TINT16}: ssa.OpAnd16, + {ir.OAND, types.TUINT16}: ssa.OpAnd16, + {ir.OAND, types.TINT32}: ssa.OpAnd32, + {ir.OAND, types.TUINT32}: ssa.OpAnd32, + {ir.OAND, types.TINT64}: ssa.OpAnd64, + {ir.OAND, types.TUINT64}: ssa.OpAnd64, + + {ir.OOR, types.TINT8}: ssa.OpOr8, + {ir.OOR, types.TUINT8}: ssa.OpOr8, + {ir.OOR, types.TINT16}: ssa.OpOr16, + {ir.OOR, types.TUINT16}: ssa.OpOr16, + {ir.OOR, types.TINT32}: ssa.OpOr32, + {ir.OOR, types.TUINT32}: ssa.OpOr32, + {ir.OOR, types.TINT64}: ssa.OpOr64, + {ir.OOR, types.TUINT64}: ssa.OpOr64, + + {ir.OXOR, types.TINT8}: ssa.OpXor8, + {ir.OXOR, types.TUINT8}: ssa.OpXor8, + {ir.OXOR, types.TINT16}: ssa.OpXor16, + {ir.OXOR, types.TUINT16}: ssa.OpXor16, + {ir.OXOR, types.TINT32}: ssa.OpXor32, + {ir.OXOR, types.TUINT32}: ssa.OpXor32, + {ir.OXOR, types.TINT64}: ssa.OpXor64, + {ir.OXOR, types.TUINT64}: ssa.OpXor64, + + {ir.OEQ, types.TBOOL}: ssa.OpEqB, + {ir.OEQ, types.TINT8}: ssa.OpEq8, + {ir.OEQ, types.TUINT8}: ssa.OpEq8, + {ir.OEQ, types.TINT16}: ssa.OpEq16, + {ir.OEQ, types.TUINT16}: ssa.OpEq16, + {ir.OEQ, types.TINT32}: ssa.OpEq32, + {ir.OEQ, types.TUINT32}: ssa.OpEq32, + {ir.OEQ, types.TINT64}: ssa.OpEq64, + {ir.OEQ, types.TUINT64}: ssa.OpEq64, + {ir.OEQ, types.TINTER}: ssa.OpEqInter, + {ir.OEQ, types.TSLICE}: ssa.OpEqSlice, + {ir.OEQ, types.TFUNC}: ssa.OpEqPtr, + {ir.OEQ, types.TMAP}: ssa.OpEqPtr, + {ir.OEQ, types.TCHAN}: ssa.OpEqPtr, + {ir.OEQ, types.TPTR}: ssa.OpEqPtr, + {ir.OEQ, types.TUINTPTR}: ssa.OpEqPtr, + {ir.OEQ, types.TUNSAFEPTR}: ssa.OpEqPtr, + {ir.OEQ, types.TFLOAT64}: ssa.OpEq64F, + {ir.OEQ, types.TFLOAT32}: ssa.OpEq32F, + + {ir.ONE, types.TBOOL}: ssa.OpNeqB, + {ir.ONE, types.TINT8}: ssa.OpNeq8, + {ir.ONE, types.TUINT8}: ssa.OpNeq8, + {ir.ONE, types.TINT16}: ssa.OpNeq16, + {ir.ONE, types.TUINT16}: ssa.OpNeq16, + {ir.ONE, types.TINT32}: ssa.OpNeq32, + {ir.ONE, types.TUINT32}: ssa.OpNeq32, + {ir.ONE, types.TINT64}: ssa.OpNeq64, + {ir.ONE, types.TUINT64}: ssa.OpNeq64, + {ir.ONE, types.TINTER}: ssa.OpNeqInter, + {ir.ONE, types.TSLICE}: ssa.OpNeqSlice, + {ir.ONE, types.TFUNC}: ssa.OpNeqPtr, + {ir.ONE, types.TMAP}: ssa.OpNeqPtr, + {ir.ONE, types.TCHAN}: ssa.OpNeqPtr, + {ir.ONE, types.TPTR}: ssa.OpNeqPtr, + {ir.ONE, types.TUINTPTR}: ssa.OpNeqPtr, + {ir.ONE, types.TUNSAFEPTR}: ssa.OpNeqPtr, + {ir.ONE, types.TFLOAT64}: ssa.OpNeq64F, + {ir.ONE, types.TFLOAT32}: ssa.OpNeq32F, + + {ir.OLT, types.TINT8}: ssa.OpLess8, + {ir.OLT, types.TUINT8}: ssa.OpLess8U, + {ir.OLT, types.TINT16}: ssa.OpLess16, + {ir.OLT, types.TUINT16}: ssa.OpLess16U, + {ir.OLT, types.TINT32}: ssa.OpLess32, + {ir.OLT, types.TUINT32}: ssa.OpLess32U, + {ir.OLT, types.TINT64}: ssa.OpLess64, + {ir.OLT, types.TUINT64}: ssa.OpLess64U, + {ir.OLT, types.TFLOAT64}: ssa.OpLess64F, + {ir.OLT, types.TFLOAT32}: ssa.OpLess32F, + + {ir.OLE, types.TINT8}: ssa.OpLeq8, + {ir.OLE, types.TUINT8}: ssa.OpLeq8U, + {ir.OLE, types.TINT16}: ssa.OpLeq16, + {ir.OLE, types.TUINT16}: ssa.OpLeq16U, + {ir.OLE, types.TINT32}: ssa.OpLeq32, + {ir.OLE, types.TUINT32}: ssa.OpLeq32U, + {ir.OLE, types.TINT64}: ssa.OpLeq64, + {ir.OLE, types.TUINT64}: ssa.OpLeq64U, + {ir.OLE, types.TFLOAT64}: ssa.OpLeq64F, + {ir.OLE, types.TFLOAT32}: ssa.OpLeq32F, +} + +func (s *state) concreteEtype(t *types.Type) types.Kind { + e := t.Kind() + switch e { + default: + return e + case types.TINT: + if s.config.PtrSize == 8 { + return types.TINT64 + } + return types.TINT32 + case types.TUINT: + if s.config.PtrSize == 8 { + return types.TUINT64 + } + return types.TUINT32 + case types.TUINTPTR: + if s.config.PtrSize == 8 { + return types.TUINT64 + } + return types.TUINT32 + } +} + +func (s *state) ssaOp(op ir.Op, t *types.Type) ssa.Op { + etype := s.concreteEtype(t) + x, ok := opToSSA[opAndType{op, etype}] + if !ok { + s.Fatalf("unhandled binary op %v %s", op, etype) + } + return x +} + +type opAndTwoTypes struct { + op ir.Op + etype1 types.Kind + etype2 types.Kind +} + +type twoTypes struct { + etype1 types.Kind + etype2 types.Kind +} + +type twoOpsAndType struct { + op1 ssa.Op + op2 ssa.Op + intermediateType types.Kind +} + +var fpConvOpToSSA = map[twoTypes]twoOpsAndType{ + + {types.TINT8, types.TFLOAT32}: {ssa.OpSignExt8to32, ssa.OpCvt32to32F, types.TINT32}, + {types.TINT16, types.TFLOAT32}: {ssa.OpSignExt16to32, ssa.OpCvt32to32F, types.TINT32}, + {types.TINT32, types.TFLOAT32}: {ssa.OpCopy, ssa.OpCvt32to32F, types.TINT32}, + {types.TINT64, types.TFLOAT32}: {ssa.OpCopy, ssa.OpCvt64to32F, types.TINT64}, + + {types.TINT8, types.TFLOAT64}: {ssa.OpSignExt8to32, ssa.OpCvt32to64F, types.TINT32}, + {types.TINT16, types.TFLOAT64}: {ssa.OpSignExt16to32, ssa.OpCvt32to64F, types.TINT32}, + {types.TINT32, types.TFLOAT64}: {ssa.OpCopy, ssa.OpCvt32to64F, types.TINT32}, + {types.TINT64, types.TFLOAT64}: {ssa.OpCopy, ssa.OpCvt64to64F, types.TINT64}, + + {types.TFLOAT32, types.TINT8}: {ssa.OpCvt32Fto32, ssa.OpTrunc32to8, types.TINT32}, + {types.TFLOAT32, types.TINT16}: {ssa.OpCvt32Fto32, ssa.OpTrunc32to16, types.TINT32}, + {types.TFLOAT32, types.TINT32}: {ssa.OpCvt32Fto32, ssa.OpCopy, types.TINT32}, + {types.TFLOAT32, types.TINT64}: {ssa.OpCvt32Fto64, ssa.OpCopy, types.TINT64}, + + {types.TFLOAT64, types.TINT8}: {ssa.OpCvt64Fto32, ssa.OpTrunc32to8, types.TINT32}, + {types.TFLOAT64, types.TINT16}: {ssa.OpCvt64Fto32, ssa.OpTrunc32to16, types.TINT32}, + {types.TFLOAT64, types.TINT32}: {ssa.OpCvt64Fto32, ssa.OpCopy, types.TINT32}, + {types.TFLOAT64, types.TINT64}: {ssa.OpCvt64Fto64, ssa.OpCopy, types.TINT64}, + // unsigned + {types.TUINT8, types.TFLOAT32}: {ssa.OpZeroExt8to32, ssa.OpCvt32to32F, types.TINT32}, + {types.TUINT16, types.TFLOAT32}: {ssa.OpZeroExt16to32, ssa.OpCvt32to32F, types.TINT32}, + {types.TUINT32, types.TFLOAT32}: {ssa.OpZeroExt32to64, ssa.OpCvt64to32F, types.TINT64}, // go wide to dodge unsigned + {types.TUINT64, types.TFLOAT32}: {ssa.OpCopy, ssa.OpInvalid, types.TUINT64}, // Cvt64Uto32F, branchy code expansion instead + + {types.TUINT8, types.TFLOAT64}: {ssa.OpZeroExt8to32, ssa.OpCvt32to64F, types.TINT32}, + {types.TUINT16, types.TFLOAT64}: {ssa.OpZeroExt16to32, ssa.OpCvt32to64F, types.TINT32}, + {types.TUINT32, types.TFLOAT64}: {ssa.OpZeroExt32to64, ssa.OpCvt64to64F, types.TINT64}, // go wide to dodge unsigned + {types.TUINT64, types.TFLOAT64}: {ssa.OpCopy, ssa.OpInvalid, types.TUINT64}, // Cvt64Uto64F, branchy code expansion instead + + {types.TFLOAT32, types.TUINT8}: {ssa.OpCvt32Fto32, ssa.OpTrunc32to8, types.TINT32}, + {types.TFLOAT32, types.TUINT16}: {ssa.OpCvt32Fto32, ssa.OpTrunc32to16, types.TINT32}, + {types.TFLOAT32, types.TUINT32}: {ssa.OpCvt32Fto64, ssa.OpTrunc64to32, types.TINT64}, // go wide to dodge unsigned + {types.TFLOAT32, types.TUINT64}: {ssa.OpInvalid, ssa.OpCopy, types.TUINT64}, // Cvt32Fto64U, branchy code expansion instead + + {types.TFLOAT64, types.TUINT8}: {ssa.OpCvt64Fto32, ssa.OpTrunc32to8, types.TINT32}, + {types.TFLOAT64, types.TUINT16}: {ssa.OpCvt64Fto32, ssa.OpTrunc32to16, types.TINT32}, + {types.TFLOAT64, types.TUINT32}: {ssa.OpCvt64Fto64, ssa.OpTrunc64to32, types.TINT64}, // go wide to dodge unsigned + {types.TFLOAT64, types.TUINT64}: {ssa.OpInvalid, ssa.OpCopy, types.TUINT64}, // Cvt64Fto64U, branchy code expansion instead + + // float + {types.TFLOAT64, types.TFLOAT32}: {ssa.OpCvt64Fto32F, ssa.OpCopy, types.TFLOAT32}, + {types.TFLOAT64, types.TFLOAT64}: {ssa.OpRound64F, ssa.OpCopy, types.TFLOAT64}, + {types.TFLOAT32, types.TFLOAT32}: {ssa.OpRound32F, ssa.OpCopy, types.TFLOAT32}, + {types.TFLOAT32, types.TFLOAT64}: {ssa.OpCvt32Fto64F, ssa.OpCopy, types.TFLOAT64}, +} + +// this map is used only for 32-bit arch, and only includes the difference +// on 32-bit arch, don't use int64<->float conversion for uint32 +var fpConvOpToSSA32 = map[twoTypes]twoOpsAndType{ + {types.TUINT32, types.TFLOAT32}: {ssa.OpCopy, ssa.OpCvt32Uto32F, types.TUINT32}, + {types.TUINT32, types.TFLOAT64}: {ssa.OpCopy, ssa.OpCvt32Uto64F, types.TUINT32}, + {types.TFLOAT32, types.TUINT32}: {ssa.OpCvt32Fto32U, ssa.OpCopy, types.TUINT32}, + {types.TFLOAT64, types.TUINT32}: {ssa.OpCvt64Fto32U, ssa.OpCopy, types.TUINT32}, +} + +// uint64<->float conversions, only on machines that have instructions for that +var uint64fpConvOpToSSA = map[twoTypes]twoOpsAndType{ + {types.TUINT64, types.TFLOAT32}: {ssa.OpCopy, ssa.OpCvt64Uto32F, types.TUINT64}, + {types.TUINT64, types.TFLOAT64}: {ssa.OpCopy, ssa.OpCvt64Uto64F, types.TUINT64}, + {types.TFLOAT32, types.TUINT64}: {ssa.OpCvt32Fto64U, ssa.OpCopy, types.TUINT64}, + {types.TFLOAT64, types.TUINT64}: {ssa.OpCvt64Fto64U, ssa.OpCopy, types.TUINT64}, +} + +var shiftOpToSSA = map[opAndTwoTypes]ssa.Op{ + {ir.OLSH, types.TINT8, types.TUINT8}: ssa.OpLsh8x8, + {ir.OLSH, types.TUINT8, types.TUINT8}: ssa.OpLsh8x8, + {ir.OLSH, types.TINT8, types.TUINT16}: ssa.OpLsh8x16, + {ir.OLSH, types.TUINT8, types.TUINT16}: ssa.OpLsh8x16, + {ir.OLSH, types.TINT8, types.TUINT32}: ssa.OpLsh8x32, + {ir.OLSH, types.TUINT8, types.TUINT32}: ssa.OpLsh8x32, + {ir.OLSH, types.TINT8, types.TUINT64}: ssa.OpLsh8x64, + {ir.OLSH, types.TUINT8, types.TUINT64}: ssa.OpLsh8x64, + + {ir.OLSH, types.TINT16, types.TUINT8}: ssa.OpLsh16x8, + {ir.OLSH, types.TUINT16, types.TUINT8}: ssa.OpLsh16x8, + {ir.OLSH, types.TINT16, types.TUINT16}: ssa.OpLsh16x16, + {ir.OLSH, types.TUINT16, types.TUINT16}: ssa.OpLsh16x16, + {ir.OLSH, types.TINT16, types.TUINT32}: ssa.OpLsh16x32, + {ir.OLSH, types.TUINT16, types.TUINT32}: ssa.OpLsh16x32, + {ir.OLSH, types.TINT16, types.TUINT64}: ssa.OpLsh16x64, + {ir.OLSH, types.TUINT16, types.TUINT64}: ssa.OpLsh16x64, + + {ir.OLSH, types.TINT32, types.TUINT8}: ssa.OpLsh32x8, + {ir.OLSH, types.TUINT32, types.TUINT8}: ssa.OpLsh32x8, + {ir.OLSH, types.TINT32, types.TUINT16}: ssa.OpLsh32x16, + {ir.OLSH, types.TUINT32, types.TUINT16}: ssa.OpLsh32x16, + {ir.OLSH, types.TINT32, types.TUINT32}: ssa.OpLsh32x32, + {ir.OLSH, types.TUINT32, types.TUINT32}: ssa.OpLsh32x32, + {ir.OLSH, types.TINT32, types.TUINT64}: ssa.OpLsh32x64, + {ir.OLSH, types.TUINT32, types.TUINT64}: ssa.OpLsh32x64, + + {ir.OLSH, types.TINT64, types.TUINT8}: ssa.OpLsh64x8, + {ir.OLSH, types.TUINT64, types.TUINT8}: ssa.OpLsh64x8, + {ir.OLSH, types.TINT64, types.TUINT16}: ssa.OpLsh64x16, + {ir.OLSH, types.TUINT64, types.TUINT16}: ssa.OpLsh64x16, + {ir.OLSH, types.TINT64, types.TUINT32}: ssa.OpLsh64x32, + {ir.OLSH, types.TUINT64, types.TUINT32}: ssa.OpLsh64x32, + {ir.OLSH, types.TINT64, types.TUINT64}: ssa.OpLsh64x64, + {ir.OLSH, types.TUINT64, types.TUINT64}: ssa.OpLsh64x64, + + {ir.ORSH, types.TINT8, types.TUINT8}: ssa.OpRsh8x8, + {ir.ORSH, types.TUINT8, types.TUINT8}: ssa.OpRsh8Ux8, + {ir.ORSH, types.TINT8, types.TUINT16}: ssa.OpRsh8x16, + {ir.ORSH, types.TUINT8, types.TUINT16}: ssa.OpRsh8Ux16, + {ir.ORSH, types.TINT8, types.TUINT32}: ssa.OpRsh8x32, + {ir.ORSH, types.TUINT8, types.TUINT32}: ssa.OpRsh8Ux32, + {ir.ORSH, types.TINT8, types.TUINT64}: ssa.OpRsh8x64, + {ir.ORSH, types.TUINT8, types.TUINT64}: ssa.OpRsh8Ux64, + + {ir.ORSH, types.TINT16, types.TUINT8}: ssa.OpRsh16x8, + {ir.ORSH, types.TUINT16, types.TUINT8}: ssa.OpRsh16Ux8, + {ir.ORSH, types.TINT16, types.TUINT16}: ssa.OpRsh16x16, + {ir.ORSH, types.TUINT16, types.TUINT16}: ssa.OpRsh16Ux16, + {ir.ORSH, types.TINT16, types.TUINT32}: ssa.OpRsh16x32, + {ir.ORSH, types.TUINT16, types.TUINT32}: ssa.OpRsh16Ux32, + {ir.ORSH, types.TINT16, types.TUINT64}: ssa.OpRsh16x64, + {ir.ORSH, types.TUINT16, types.TUINT64}: ssa.OpRsh16Ux64, + + {ir.ORSH, types.TINT32, types.TUINT8}: ssa.OpRsh32x8, + {ir.ORSH, types.TUINT32, types.TUINT8}: ssa.OpRsh32Ux8, + {ir.ORSH, types.TINT32, types.TUINT16}: ssa.OpRsh32x16, + {ir.ORSH, types.TUINT32, types.TUINT16}: ssa.OpRsh32Ux16, + {ir.ORSH, types.TINT32, types.TUINT32}: ssa.OpRsh32x32, + {ir.ORSH, types.TUINT32, types.TUINT32}: ssa.OpRsh32Ux32, + {ir.ORSH, types.TINT32, types.TUINT64}: ssa.OpRsh32x64, + {ir.ORSH, types.TUINT32, types.TUINT64}: ssa.OpRsh32Ux64, + + {ir.ORSH, types.TINT64, types.TUINT8}: ssa.OpRsh64x8, + {ir.ORSH, types.TUINT64, types.TUINT8}: ssa.OpRsh64Ux8, + {ir.ORSH, types.TINT64, types.TUINT16}: ssa.OpRsh64x16, + {ir.ORSH, types.TUINT64, types.TUINT16}: ssa.OpRsh64Ux16, + {ir.ORSH, types.TINT64, types.TUINT32}: ssa.OpRsh64x32, + {ir.ORSH, types.TUINT64, types.TUINT32}: ssa.OpRsh64Ux32, + {ir.ORSH, types.TINT64, types.TUINT64}: ssa.OpRsh64x64, + {ir.ORSH, types.TUINT64, types.TUINT64}: ssa.OpRsh64Ux64, +} + +func (s *state) ssaShiftOp(op ir.Op, t *types.Type, u *types.Type) ssa.Op { + etype1 := s.concreteEtype(t) + etype2 := s.concreteEtype(u) + x, ok := shiftOpToSSA[opAndTwoTypes{op, etype1, etype2}] + if !ok { + s.Fatalf("unhandled shift op %v etype=%s/%s", op, etype1, etype2) + } + return x +} + +func (s *state) uintptrConstant(v uint64) *ssa.Value { + if s.config.PtrSize == 4 { + return s.newValue0I(ssa.OpConst32, types.Types[types.TUINTPTR], int64(v)) + } + return s.newValue0I(ssa.OpConst64, types.Types[types.TUINTPTR], int64(v)) +} + +func (s *state) conv(n ir.Node, v *ssa.Value, ft, tt *types.Type) *ssa.Value { + if ft.IsBoolean() && tt.IsKind(types.TUINT8) { + // Bool -> uint8 is generated internally when indexing into runtime.staticbyte. + return s.newValue1(ssa.OpCvtBoolToUint8, tt, v) + } + if ft.IsInteger() && tt.IsInteger() { + var op ssa.Op + if tt.Size() == ft.Size() { + op = ssa.OpCopy + } else if tt.Size() < ft.Size() { + // truncation + switch 10*ft.Size() + tt.Size() { + case 21: + op = ssa.OpTrunc16to8 + case 41: + op = ssa.OpTrunc32to8 + case 42: + op = ssa.OpTrunc32to16 + case 81: + op = ssa.OpTrunc64to8 + case 82: + op = ssa.OpTrunc64to16 + case 84: + op = ssa.OpTrunc64to32 + default: + s.Fatalf("weird integer truncation %v -> %v", ft, tt) + } + } else if ft.IsSigned() { + // sign extension + switch 10*ft.Size() + tt.Size() { + case 12: + op = ssa.OpSignExt8to16 + case 14: + op = ssa.OpSignExt8to32 + case 18: + op = ssa.OpSignExt8to64 + case 24: + op = ssa.OpSignExt16to32 + case 28: + op = ssa.OpSignExt16to64 + case 48: + op = ssa.OpSignExt32to64 + default: + s.Fatalf("bad integer sign extension %v -> %v", ft, tt) + } + } else { + // zero extension + switch 10*ft.Size() + tt.Size() { + case 12: + op = ssa.OpZeroExt8to16 + case 14: + op = ssa.OpZeroExt8to32 + case 18: + op = ssa.OpZeroExt8to64 + case 24: + op = ssa.OpZeroExt16to32 + case 28: + op = ssa.OpZeroExt16to64 + case 48: + op = ssa.OpZeroExt32to64 + default: + s.Fatalf("weird integer sign extension %v -> %v", ft, tt) + } + } + return s.newValue1(op, tt, v) + } + + if ft.IsComplex() && tt.IsComplex() { + var op ssa.Op + if ft.Size() == tt.Size() { + switch ft.Size() { + case 8: + op = ssa.OpRound32F + case 16: + op = ssa.OpRound64F + default: + s.Fatalf("weird complex conversion %v -> %v", ft, tt) + } + } else if ft.Size() == 8 && tt.Size() == 16 { + op = ssa.OpCvt32Fto64F + } else if ft.Size() == 16 && tt.Size() == 8 { + op = ssa.OpCvt64Fto32F + } else { + s.Fatalf("weird complex conversion %v -> %v", ft, tt) + } + ftp := types.FloatForComplex(ft) + ttp := types.FloatForComplex(tt) + return s.newValue2(ssa.OpComplexMake, tt, + s.newValueOrSfCall1(op, ttp, s.newValue1(ssa.OpComplexReal, ftp, v)), + s.newValueOrSfCall1(op, ttp, s.newValue1(ssa.OpComplexImag, ftp, v))) + } + + if tt.IsComplex() { // and ft is not complex + // Needed for generics support - can't happen in normal Go code. + et := types.FloatForComplex(tt) + v = s.conv(n, v, ft, et) + return s.newValue2(ssa.OpComplexMake, tt, v, s.zeroVal(et)) + } + + if ft.IsFloat() || tt.IsFloat() { + conv, ok := fpConvOpToSSA[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}] + if s.config.RegSize == 4 && Arch.LinkArch.Family != sys.MIPS && !s.softFloat { + if conv1, ok1 := fpConvOpToSSA32[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]; ok1 { + conv = conv1 + } + } + if Arch.LinkArch.Family == sys.ARM64 || Arch.LinkArch.Family == sys.Wasm || Arch.LinkArch.Family == sys.S390X || s.softFloat { + if conv1, ok1 := uint64fpConvOpToSSA[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]; ok1 { + conv = conv1 + } + } + + if Arch.LinkArch.Family == sys.MIPS && !s.softFloat { + if ft.Size() == 4 && ft.IsInteger() && !ft.IsSigned() { + // tt is float32 or float64, and ft is also unsigned + if tt.Size() == 4 { + return s.uint32Tofloat32(n, v, ft, tt) + } + if tt.Size() == 8 { + return s.uint32Tofloat64(n, v, ft, tt) + } + } else if tt.Size() == 4 && tt.IsInteger() && !tt.IsSigned() { + // ft is float32 or float64, and tt is unsigned integer + if ft.Size() == 4 { + return s.float32ToUint32(n, v, ft, tt) + } + if ft.Size() == 8 { + return s.float64ToUint32(n, v, ft, tt) + } + } + } + + if !ok { + s.Fatalf("weird float conversion %v -> %v", ft, tt) + } + op1, op2, it := conv.op1, conv.op2, conv.intermediateType + + if op1 != ssa.OpInvalid && op2 != ssa.OpInvalid { + // normal case, not tripping over unsigned 64 + if op1 == ssa.OpCopy { + if op2 == ssa.OpCopy { + return v + } + return s.newValueOrSfCall1(op2, tt, v) + } + if op2 == ssa.OpCopy { + return s.newValueOrSfCall1(op1, tt, v) + } + return s.newValueOrSfCall1(op2, tt, s.newValueOrSfCall1(op1, types.Types[it], v)) + } + // Tricky 64-bit unsigned cases. + if ft.IsInteger() { + // tt is float32 or float64, and ft is also unsigned + if tt.Size() == 4 { + return s.uint64Tofloat32(n, v, ft, tt) + } + if tt.Size() == 8 { + return s.uint64Tofloat64(n, v, ft, tt) + } + s.Fatalf("weird unsigned integer to float conversion %v -> %v", ft, tt) + } + // ft is float32 or float64, and tt is unsigned integer + if ft.Size() == 4 { + return s.float32ToUint64(n, v, ft, tt) + } + if ft.Size() == 8 { + return s.float64ToUint64(n, v, ft, tt) + } + s.Fatalf("weird float to unsigned integer conversion %v -> %v", ft, tt) + return nil + } + + s.Fatalf("unhandled OCONV %s -> %s", ft.Kind(), tt.Kind()) + return nil +} + +// expr converts the expression n to ssa, adds it to s and returns the ssa result. +func (s *state) expr(n ir.Node) *ssa.Value { + return s.exprCheckPtr(n, true) +} + +func (s *state) exprCheckPtr(n ir.Node, checkPtrOK bool) *ssa.Value { + if ir.HasUniquePos(n) { + // ONAMEs and named OLITERALs have the line number + // of the decl, not the use. See issue 14742. + s.pushLine(n.Pos()) + defer s.popLine() + } + + s.stmtList(n.Init()) + switch n.Op() { + case ir.OBYTES2STRTMP: + n := n.(*ir.ConvExpr) + slice := s.expr(n.X) + ptr := s.newValue1(ssa.OpSlicePtr, s.f.Config.Types.BytePtr, slice) + len := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], slice) + return s.newValue2(ssa.OpStringMake, n.Type(), ptr, len) + case ir.OSTR2BYTESTMP: + n := n.(*ir.ConvExpr) + str := s.expr(n.X) + ptr := s.newValue1(ssa.OpStringPtr, s.f.Config.Types.BytePtr, str) + len := s.newValue1(ssa.OpStringLen, types.Types[types.TINT], str) + return s.newValue3(ssa.OpSliceMake, n.Type(), ptr, len, len) + case ir.OCFUNC: + n := n.(*ir.UnaryExpr) + aux := n.X.(*ir.Name).Linksym() + // OCFUNC is used to build function values, which must + // always reference ABIInternal entry points. + if aux.ABI() != obj.ABIInternal { + s.Fatalf("expected ABIInternal: %v", aux.ABI()) + } + return s.entryNewValue1A(ssa.OpAddr, n.Type(), aux, s.sb) + case ir.ONAME: + n := n.(*ir.Name) + if n.Class == ir.PFUNC { + // "value" of a function is the address of the function's closure + sym := staticdata.FuncLinksym(n) + return s.entryNewValue1A(ssa.OpAddr, types.NewPtr(n.Type()), sym, s.sb) + } + if s.canSSA(n) { + return s.variable(n, n.Type()) + } + return s.load(n.Type(), s.addr(n)) + case ir.OLINKSYMOFFSET: + n := n.(*ir.LinksymOffsetExpr) + return s.load(n.Type(), s.addr(n)) + case ir.ONIL: + n := n.(*ir.NilExpr) + t := n.Type() + switch { + case t.IsSlice(): + return s.constSlice(t) + case t.IsInterface(): + return s.constInterface(t) + default: + return s.constNil(t) + } + case ir.OLITERAL: + switch u := n.Val(); u.Kind() { + case constant.Int: + i := ir.IntVal(n.Type(), u) + switch n.Type().Size() { + case 1: + return s.constInt8(n.Type(), int8(i)) + case 2: + return s.constInt16(n.Type(), int16(i)) + case 4: + return s.constInt32(n.Type(), int32(i)) + case 8: + return s.constInt64(n.Type(), i) + default: + s.Fatalf("bad integer size %d", n.Type().Size()) + return nil + } + case constant.String: + i := constant.StringVal(u) + if i == "" { + return s.constEmptyString(n.Type()) + } + return s.entryNewValue0A(ssa.OpConstString, n.Type(), ssa.StringToAux(i)) + case constant.Bool: + return s.constBool(constant.BoolVal(u)) + case constant.Float: + f, _ := constant.Float64Val(u) + switch n.Type().Size() { + case 4: + return s.constFloat32(n.Type(), f) + case 8: + return s.constFloat64(n.Type(), f) + default: + s.Fatalf("bad float size %d", n.Type().Size()) + return nil + } + case constant.Complex: + re, _ := constant.Float64Val(constant.Real(u)) + im, _ := constant.Float64Val(constant.Imag(u)) + switch n.Type().Size() { + case 8: + pt := types.Types[types.TFLOAT32] + return s.newValue2(ssa.OpComplexMake, n.Type(), + s.constFloat32(pt, re), + s.constFloat32(pt, im)) + case 16: + pt := types.Types[types.TFLOAT64] + return s.newValue2(ssa.OpComplexMake, n.Type(), + s.constFloat64(pt, re), + s.constFloat64(pt, im)) + default: + s.Fatalf("bad complex size %d", n.Type().Size()) + return nil + } + default: + s.Fatalf("unhandled OLITERAL %v", u.Kind()) + return nil + } + case ir.OCONVNOP: + n := n.(*ir.ConvExpr) + to := n.Type() + from := n.X.Type() + + // Assume everything will work out, so set up our return value. + // Anything interesting that happens from here is a fatal. + x := s.expr(n.X) + if to == from { + return x + } + + // Special case for not confusing GC and liveness. + // We don't want pointers accidentally classified + // as not-pointers or vice-versa because of copy + // elision. + if to.IsPtrShaped() != from.IsPtrShaped() { + return s.newValue2(ssa.OpConvert, to, x, s.mem()) + } + + v := s.newValue1(ssa.OpCopy, to, x) // ensure that v has the right type + + // CONVNOP closure + if to.Kind() == types.TFUNC && from.IsPtrShaped() { + return v + } + + // named <--> unnamed type or typed <--> untyped const + if from.Kind() == to.Kind() { + return v + } + + // unsafe.Pointer <--> *T + if to.IsUnsafePtr() && from.IsPtrShaped() || from.IsUnsafePtr() && to.IsPtrShaped() { + if s.checkPtrEnabled && checkPtrOK && to.IsPtr() && from.IsUnsafePtr() { + s.checkPtrAlignment(n, v, nil) + } + return v + } + + // map <--> *hmap + if to.Kind() == types.TMAP && from.IsPtr() && + to.MapType().Hmap == from.Elem() { + return v + } + + types.CalcSize(from) + types.CalcSize(to) + if from.Size() != to.Size() { + s.Fatalf("CONVNOP width mismatch %v (%d) -> %v (%d)\n", from, from.Size(), to, to.Size()) + return nil + } + if etypesign(from.Kind()) != etypesign(to.Kind()) { + s.Fatalf("CONVNOP sign mismatch %v (%s) -> %v (%s)\n", from, from.Kind(), to, to.Kind()) + return nil + } + + if base.Flag.Cfg.Instrumenting { + // These appear to be fine, but they fail the + // integer constraint below, so okay them here. + // Sample non-integer conversion: map[string]string -> *uint8 + return v + } + + if etypesign(from.Kind()) == 0 { + s.Fatalf("CONVNOP unrecognized non-integer %v -> %v\n", from, to) + return nil + } + + // integer, same width, same sign + return v + + case ir.OCONV: + n := n.(*ir.ConvExpr) + x := s.expr(n.X) + return s.conv(n, x, n.X.Type(), n.Type()) + + case ir.ODOTTYPE: + n := n.(*ir.TypeAssertExpr) + res, _ := s.dottype(n, false) + return res + + case ir.ODYNAMICDOTTYPE: + n := n.(*ir.DynamicTypeAssertExpr) + res, _ := s.dynamicDottype(n, false) + return res + + // binary ops + case ir.OLT, ir.OEQ, ir.ONE, ir.OLE, ir.OGE, ir.OGT: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + if n.X.Type().IsComplex() { + pt := types.FloatForComplex(n.X.Type()) + op := s.ssaOp(ir.OEQ, pt) + r := s.newValueOrSfCall2(op, types.Types[types.TBOOL], s.newValue1(ssa.OpComplexReal, pt, a), s.newValue1(ssa.OpComplexReal, pt, b)) + i := s.newValueOrSfCall2(op, types.Types[types.TBOOL], s.newValue1(ssa.OpComplexImag, pt, a), s.newValue1(ssa.OpComplexImag, pt, b)) + c := s.newValue2(ssa.OpAndB, types.Types[types.TBOOL], r, i) + switch n.Op() { + case ir.OEQ: + return c + case ir.ONE: + return s.newValue1(ssa.OpNot, types.Types[types.TBOOL], c) + default: + s.Fatalf("ordered complex compare %v", n.Op()) + } + } + + // Convert OGE and OGT into OLE and OLT. + op := n.Op() + switch op { + case ir.OGE: + op, a, b = ir.OLE, b, a + case ir.OGT: + op, a, b = ir.OLT, b, a + } + if n.X.Type().IsFloat() { + // float comparison + return s.newValueOrSfCall2(s.ssaOp(op, n.X.Type()), types.Types[types.TBOOL], a, b) + } + // integer comparison + return s.newValue2(s.ssaOp(op, n.X.Type()), types.Types[types.TBOOL], a, b) + case ir.OMUL: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + if n.Type().IsComplex() { + mulop := ssa.OpMul64F + addop := ssa.OpAdd64F + subop := ssa.OpSub64F + pt := types.FloatForComplex(n.Type()) // Could be Float32 or Float64 + wt := types.Types[types.TFLOAT64] // Compute in Float64 to minimize cancellation error + + areal := s.newValue1(ssa.OpComplexReal, pt, a) + breal := s.newValue1(ssa.OpComplexReal, pt, b) + aimag := s.newValue1(ssa.OpComplexImag, pt, a) + bimag := s.newValue1(ssa.OpComplexImag, pt, b) + + if pt != wt { // Widen for calculation + areal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, areal) + breal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, breal) + aimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, aimag) + bimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, bimag) + } + + xreal := s.newValueOrSfCall2(subop, wt, s.newValueOrSfCall2(mulop, wt, areal, breal), s.newValueOrSfCall2(mulop, wt, aimag, bimag)) + ximag := s.newValueOrSfCall2(addop, wt, s.newValueOrSfCall2(mulop, wt, areal, bimag), s.newValueOrSfCall2(mulop, wt, aimag, breal)) + + if pt != wt { // Narrow to store back + xreal = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, xreal) + ximag = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, ximag) + } + + return s.newValue2(ssa.OpComplexMake, n.Type(), xreal, ximag) + } + + if n.Type().IsFloat() { + return s.newValueOrSfCall2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b) + } + + return s.newValue2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b) + + case ir.ODIV: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + if n.Type().IsComplex() { + // TODO this is not executed because the front-end substitutes a runtime call. + // That probably ought to change; with modest optimization the widen/narrow + // conversions could all be elided in larger expression trees. + mulop := ssa.OpMul64F + addop := ssa.OpAdd64F + subop := ssa.OpSub64F + divop := ssa.OpDiv64F + pt := types.FloatForComplex(n.Type()) // Could be Float32 or Float64 + wt := types.Types[types.TFLOAT64] // Compute in Float64 to minimize cancellation error + + areal := s.newValue1(ssa.OpComplexReal, pt, a) + breal := s.newValue1(ssa.OpComplexReal, pt, b) + aimag := s.newValue1(ssa.OpComplexImag, pt, a) + bimag := s.newValue1(ssa.OpComplexImag, pt, b) + + if pt != wt { // Widen for calculation + areal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, areal) + breal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, breal) + aimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, aimag) + bimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, bimag) + } + + denom := s.newValueOrSfCall2(addop, wt, s.newValueOrSfCall2(mulop, wt, breal, breal), s.newValueOrSfCall2(mulop, wt, bimag, bimag)) + xreal := s.newValueOrSfCall2(addop, wt, s.newValueOrSfCall2(mulop, wt, areal, breal), s.newValueOrSfCall2(mulop, wt, aimag, bimag)) + ximag := s.newValueOrSfCall2(subop, wt, s.newValueOrSfCall2(mulop, wt, aimag, breal), s.newValueOrSfCall2(mulop, wt, areal, bimag)) + + // TODO not sure if this is best done in wide precision or narrow + // Double-rounding might be an issue. + // Note that the pre-SSA implementation does the entire calculation + // in wide format, so wide is compatible. + xreal = s.newValueOrSfCall2(divop, wt, xreal, denom) + ximag = s.newValueOrSfCall2(divop, wt, ximag, denom) + + if pt != wt { // Narrow to store back + xreal = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, xreal) + ximag = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, ximag) + } + return s.newValue2(ssa.OpComplexMake, n.Type(), xreal, ximag) + } + if n.Type().IsFloat() { + return s.newValueOrSfCall2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b) + } + return s.intDivide(n, a, b) + case ir.OMOD: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + return s.intDivide(n, a, b) + case ir.OADD, ir.OSUB: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + if n.Type().IsComplex() { + pt := types.FloatForComplex(n.Type()) + op := s.ssaOp(n.Op(), pt) + return s.newValue2(ssa.OpComplexMake, n.Type(), + s.newValueOrSfCall2(op, pt, s.newValue1(ssa.OpComplexReal, pt, a), s.newValue1(ssa.OpComplexReal, pt, b)), + s.newValueOrSfCall2(op, pt, s.newValue1(ssa.OpComplexImag, pt, a), s.newValue1(ssa.OpComplexImag, pt, b))) + } + if n.Type().IsFloat() { + return s.newValueOrSfCall2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b) + } + return s.newValue2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b) + case ir.OAND, ir.OOR, ir.OXOR: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + return s.newValue2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b) + case ir.OANDNOT: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + b = s.newValue1(s.ssaOp(ir.OBITNOT, b.Type), b.Type, b) + return s.newValue2(s.ssaOp(ir.OAND, n.Type()), a.Type, a, b) + case ir.OLSH, ir.ORSH: + n := n.(*ir.BinaryExpr) + a := s.expr(n.X) + b := s.expr(n.Y) + bt := b.Type + if bt.IsSigned() { + cmp := s.newValue2(s.ssaOp(ir.OLE, bt), types.Types[types.TBOOL], s.zeroVal(bt), b) + s.check(cmp, ir.Syms.Panicshift) + bt = bt.ToUnsigned() + } + return s.newValue2(s.ssaShiftOp(n.Op(), n.Type(), bt), a.Type, a, b) + case ir.OANDAND, ir.OOROR: + // To implement OANDAND (and OOROR), we introduce a + // new temporary variable to hold the result. The + // variable is associated with the OANDAND node in the + // s.vars table (normally variables are only + // associated with ONAME nodes). We convert + // A && B + // to + // var = A + // if var { + // var = B + // } + // Using var in the subsequent block introduces the + // necessary phi variable. + n := n.(*ir.LogicalExpr) + el := s.expr(n.X) + s.vars[n] = el + + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(el) + // In theory, we should set b.Likely here based on context. + // However, gc only gives us likeliness hints + // in a single place, for plain OIF statements, + // and passing around context is finnicky, so don't bother for now. + + bRight := s.f.NewBlock(ssa.BlockPlain) + bResult := s.f.NewBlock(ssa.BlockPlain) + if n.Op() == ir.OANDAND { + b.AddEdgeTo(bRight) + b.AddEdgeTo(bResult) + } else if n.Op() == ir.OOROR { + b.AddEdgeTo(bResult) + b.AddEdgeTo(bRight) + } + + s.startBlock(bRight) + er := s.expr(n.Y) + s.vars[n] = er + + b = s.endBlock() + b.AddEdgeTo(bResult) + + s.startBlock(bResult) + return s.variable(n, types.Types[types.TBOOL]) + case ir.OCOMPLEX: + n := n.(*ir.BinaryExpr) + r := s.expr(n.X) + i := s.expr(n.Y) + return s.newValue2(ssa.OpComplexMake, n.Type(), r, i) + + // unary ops + case ir.ONEG: + n := n.(*ir.UnaryExpr) + a := s.expr(n.X) + if n.Type().IsComplex() { + tp := types.FloatForComplex(n.Type()) + negop := s.ssaOp(n.Op(), tp) + return s.newValue2(ssa.OpComplexMake, n.Type(), + s.newValue1(negop, tp, s.newValue1(ssa.OpComplexReal, tp, a)), + s.newValue1(negop, tp, s.newValue1(ssa.OpComplexImag, tp, a))) + } + return s.newValue1(s.ssaOp(n.Op(), n.Type()), a.Type, a) + case ir.ONOT, ir.OBITNOT: + n := n.(*ir.UnaryExpr) + a := s.expr(n.X) + return s.newValue1(s.ssaOp(n.Op(), n.Type()), a.Type, a) + case ir.OIMAG, ir.OREAL: + n := n.(*ir.UnaryExpr) + a := s.expr(n.X) + return s.newValue1(s.ssaOp(n.Op(), n.X.Type()), n.Type(), a) + case ir.OPLUS: + n := n.(*ir.UnaryExpr) + return s.expr(n.X) + + case ir.OADDR: + n := n.(*ir.AddrExpr) + return s.addr(n.X) + + case ir.ORESULT: + n := n.(*ir.ResultExpr) + if s.prevCall == nil || s.prevCall.Op != ssa.OpStaticLECall && s.prevCall.Op != ssa.OpInterLECall && s.prevCall.Op != ssa.OpClosureLECall { + panic("Expected to see a previous call") + } + which := n.Index + if which == -1 { + panic(fmt.Errorf("ORESULT %v does not match call %s", n, s.prevCall)) + } + return s.resultOfCall(s.prevCall, which, n.Type()) + + case ir.ODEREF: + n := n.(*ir.StarExpr) + p := s.exprPtr(n.X, n.Bounded(), n.Pos()) + return s.load(n.Type(), p) + + case ir.ODOT: + n := n.(*ir.SelectorExpr) + if n.X.Op() == ir.OSTRUCTLIT { + // All literals with nonzero fields have already been + // rewritten during walk. Any that remain are just T{} + // or equivalents. Use the zero value. + if !ir.IsZero(n.X) { + s.Fatalf("literal with nonzero value in SSA: %v", n.X) + } + return s.zeroVal(n.Type()) + } + // If n is addressable and can't be represented in + // SSA, then load just the selected field. This + // prevents false memory dependencies in race/msan/asan + // instrumentation. + if ir.IsAddressable(n) && !s.canSSA(n) { + p := s.addr(n) + return s.load(n.Type(), p) + } + v := s.expr(n.X) + return s.newValue1I(ssa.OpStructSelect, n.Type(), int64(fieldIdx(n)), v) + + case ir.ODOTPTR: + n := n.(*ir.SelectorExpr) + p := s.exprPtr(n.X, n.Bounded(), n.Pos()) + p = s.newValue1I(ssa.OpOffPtr, types.NewPtr(n.Type()), n.Offset(), p) + return s.load(n.Type(), p) + + case ir.OINDEX: + n := n.(*ir.IndexExpr) + switch { + case n.X.Type().IsString(): + if n.Bounded() && ir.IsConst(n.X, constant.String) && ir.IsConst(n.Index, constant.Int) { + // Replace "abc"[1] with 'b'. + // Delayed until now because "abc"[1] is not an ideal constant. + // See test/fixedbugs/issue11370.go. + return s.newValue0I(ssa.OpConst8, types.Types[types.TUINT8], int64(int8(ir.StringVal(n.X)[ir.Int64Val(n.Index)]))) + } + a := s.expr(n.X) + i := s.expr(n.Index) + len := s.newValue1(ssa.OpStringLen, types.Types[types.TINT], a) + i = s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded()) + ptrtyp := s.f.Config.Types.BytePtr + ptr := s.newValue1(ssa.OpStringPtr, ptrtyp, a) + if ir.IsConst(n.Index, constant.Int) { + ptr = s.newValue1I(ssa.OpOffPtr, ptrtyp, ir.Int64Val(n.Index), ptr) + } else { + ptr = s.newValue2(ssa.OpAddPtr, ptrtyp, ptr, i) + } + return s.load(types.Types[types.TUINT8], ptr) + case n.X.Type().IsSlice(): + p := s.addr(n) + return s.load(n.X.Type().Elem(), p) + case n.X.Type().IsArray(): + if TypeOK(n.X.Type()) { + // SSA can handle arrays of length at most 1. + bound := n.X.Type().NumElem() + a := s.expr(n.X) + i := s.expr(n.Index) + if bound == 0 { + // Bounds check will never succeed. Might as well + // use constants for the bounds check. + z := s.constInt(types.Types[types.TINT], 0) + s.boundsCheck(z, z, ssa.BoundsIndex, false) + // The return value won't be live, return junk. + // But not quite junk, in case bounds checks are turned off. See issue 48092. + return s.zeroVal(n.Type()) + } + len := s.constInt(types.Types[types.TINT], bound) + s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded()) // checks i == 0 + return s.newValue1I(ssa.OpArraySelect, n.Type(), 0, a) + } + p := s.addr(n) + return s.load(n.X.Type().Elem(), p) + default: + s.Fatalf("bad type for index %v", n.X.Type()) + return nil + } + + case ir.OLEN, ir.OCAP: + n := n.(*ir.UnaryExpr) + switch { + case n.X.Type().IsSlice(): + op := ssa.OpSliceLen + if n.Op() == ir.OCAP { + op = ssa.OpSliceCap + } + return s.newValue1(op, types.Types[types.TINT], s.expr(n.X)) + case n.X.Type().IsString(): // string; not reachable for OCAP + return s.newValue1(ssa.OpStringLen, types.Types[types.TINT], s.expr(n.X)) + case n.X.Type().IsMap(), n.X.Type().IsChan(): + return s.referenceTypeBuiltin(n, s.expr(n.X)) + default: // array + return s.constInt(types.Types[types.TINT], n.X.Type().NumElem()) + } + + case ir.OSPTR: + n := n.(*ir.UnaryExpr) + a := s.expr(n.X) + if n.X.Type().IsSlice() { + if n.Bounded() { + return s.newValue1(ssa.OpSlicePtr, n.Type(), a) + } + return s.newValue1(ssa.OpSlicePtrUnchecked, n.Type(), a) + } else { + return s.newValue1(ssa.OpStringPtr, n.Type(), a) + } + + case ir.OITAB: + n := n.(*ir.UnaryExpr) + a := s.expr(n.X) + return s.newValue1(ssa.OpITab, n.Type(), a) + + case ir.OIDATA: + n := n.(*ir.UnaryExpr) + a := s.expr(n.X) + return s.newValue1(ssa.OpIData, n.Type(), a) + + case ir.OEFACE: + n := n.(*ir.BinaryExpr) + tab := s.expr(n.X) + data := s.expr(n.Y) + return s.newValue2(ssa.OpIMake, n.Type(), tab, data) + + case ir.OSLICEHEADER: + n := n.(*ir.SliceHeaderExpr) + p := s.expr(n.Ptr) + l := s.expr(n.Len) + c := s.expr(n.Cap) + return s.newValue3(ssa.OpSliceMake, n.Type(), p, l, c) + + case ir.OSTRINGHEADER: + n := n.(*ir.StringHeaderExpr) + p := s.expr(n.Ptr) + l := s.expr(n.Len) + return s.newValue2(ssa.OpStringMake, n.Type(), p, l) + + case ir.OSLICE, ir.OSLICEARR, ir.OSLICE3, ir.OSLICE3ARR: + n := n.(*ir.SliceExpr) + check := s.checkPtrEnabled && n.Op() == ir.OSLICE3ARR && n.X.Op() == ir.OCONVNOP && n.X.(*ir.ConvExpr).X.Type().IsUnsafePtr() + v := s.exprCheckPtr(n.X, !check) + var i, j, k *ssa.Value + if n.Low != nil { + i = s.expr(n.Low) + } + if n.High != nil { + j = s.expr(n.High) + } + if n.Max != nil { + k = s.expr(n.Max) + } + p, l, c := s.slice(v, i, j, k, n.Bounded()) + if check { + // Emit checkptr instrumentation after bound check to prevent false positive, see #46938. + s.checkPtrAlignment(n.X.(*ir.ConvExpr), v, s.conv(n.Max, k, k.Type, types.Types[types.TUINTPTR])) + } + return s.newValue3(ssa.OpSliceMake, n.Type(), p, l, c) + + case ir.OSLICESTR: + n := n.(*ir.SliceExpr) + v := s.expr(n.X) + var i, j *ssa.Value + if n.Low != nil { + i = s.expr(n.Low) + } + if n.High != nil { + j = s.expr(n.High) + } + p, l, _ := s.slice(v, i, j, nil, n.Bounded()) + return s.newValue2(ssa.OpStringMake, n.Type(), p, l) + + case ir.OSLICE2ARRPTR: + // if arrlen > slice.len { + // panic(...) + // } + // slice.ptr + n := n.(*ir.ConvExpr) + v := s.expr(n.X) + nelem := n.Type().Elem().NumElem() + arrlen := s.constInt(types.Types[types.TINT], nelem) + cap := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], v) + s.boundsCheck(arrlen, cap, ssa.BoundsConvert, false) + op := ssa.OpSlicePtr + if nelem == 0 { + op = ssa.OpSlicePtrUnchecked + } + return s.newValue1(op, n.Type(), v) + + case ir.OCALLFUNC: + n := n.(*ir.CallExpr) + if ir.IsIntrinsicCall(n) { + return s.intrinsicCall(n) + } + fallthrough + + case ir.OCALLINTER: + n := n.(*ir.CallExpr) + return s.callResult(n, callNormal) + + case ir.OGETG: + n := n.(*ir.CallExpr) + return s.newValue1(ssa.OpGetG, n.Type(), s.mem()) + + case ir.OGETCALLERPC: + n := n.(*ir.CallExpr) + return s.newValue0(ssa.OpGetCallerPC, n.Type()) + + case ir.OGETCALLERSP: + n := n.(*ir.CallExpr) + return s.newValue1(ssa.OpGetCallerSP, n.Type(), s.mem()) + + case ir.OAPPEND: + return s.append(n.(*ir.CallExpr), false) + + case ir.OMIN, ir.OMAX: + return s.minMax(n.(*ir.CallExpr)) + + case ir.OSTRUCTLIT, ir.OARRAYLIT: + // All literals with nonzero fields have already been + // rewritten during walk. Any that remain are just T{} + // or equivalents. Use the zero value. + n := n.(*ir.CompLitExpr) + if !ir.IsZero(n) { + s.Fatalf("literal with nonzero value in SSA: %v", n) + } + return s.zeroVal(n.Type()) + + case ir.ONEW: + n := n.(*ir.UnaryExpr) + var rtype *ssa.Value + if x, ok := n.X.(*ir.DynamicType); ok && x.Op() == ir.ODYNAMICTYPE { + rtype = s.expr(x.RType) + } + return s.newObject(n.Type().Elem(), rtype) + + case ir.OUNSAFEADD: + n := n.(*ir.BinaryExpr) + ptr := s.expr(n.X) + len := s.expr(n.Y) + + // Force len to uintptr to prevent misuse of garbage bits in the + // upper part of the register (#48536). + len = s.conv(n, len, len.Type, types.Types[types.TUINTPTR]) + + return s.newValue2(ssa.OpAddPtr, n.Type(), ptr, len) + + default: + s.Fatalf("unhandled expr %v", n.Op()) + return nil + } +} + +func (s *state) resultOfCall(c *ssa.Value, which int64, t *types.Type) *ssa.Value { + aux := c.Aux.(*ssa.AuxCall) + pa := aux.ParamAssignmentForResult(which) + // TODO(register args) determine if in-memory TypeOK is better loaded early from SelectNAddr or later when SelectN is expanded. + // SelectN is better for pattern-matching and possible call-aware analysis we might want to do in the future. + if len(pa.Registers) == 0 && !TypeOK(t) { + addr := s.newValue1I(ssa.OpSelectNAddr, types.NewPtr(t), which, c) + return s.rawLoad(t, addr) + } + return s.newValue1I(ssa.OpSelectN, t, which, c) +} + +func (s *state) resultAddrOfCall(c *ssa.Value, which int64, t *types.Type) *ssa.Value { + aux := c.Aux.(*ssa.AuxCall) + pa := aux.ParamAssignmentForResult(which) + if len(pa.Registers) == 0 { + return s.newValue1I(ssa.OpSelectNAddr, types.NewPtr(t), which, c) + } + _, addr := s.temp(c.Pos, t) + rval := s.newValue1I(ssa.OpSelectN, t, which, c) + s.vars[memVar] = s.newValue3Apos(ssa.OpStore, types.TypeMem, t, addr, rval, s.mem(), false) + return addr +} + +// append converts an OAPPEND node to SSA. +// If inplace is false, it converts the OAPPEND expression n to an ssa.Value, +// adds it to s, and returns the Value. +// If inplace is true, it writes the result of the OAPPEND expression n +// back to the slice being appended to, and returns nil. +// inplace MUST be set to false if the slice can be SSA'd. +// Note: this code only handles fixed-count appends. Dotdotdot appends +// have already been rewritten at this point (by walk). +func (s *state) append(n *ir.CallExpr, inplace bool) *ssa.Value { + // If inplace is false, process as expression "append(s, e1, e2, e3)": + // + // ptr, len, cap := s + // len += 3 + // if uint(len) > uint(cap) { + // ptr, len, cap = growslice(ptr, len, cap, 3, typ) + // Note that len is unmodified by growslice. + // } + // // with write barriers, if needed: + // *(ptr+(len-3)) = e1 + // *(ptr+(len-2)) = e2 + // *(ptr+(len-1)) = e3 + // return makeslice(ptr, len, cap) + // + // + // If inplace is true, process as statement "s = append(s, e1, e2, e3)": + // + // a := &s + // ptr, len, cap := s + // len += 3 + // if uint(len) > uint(cap) { + // ptr, len, cap = growslice(ptr, len, cap, 3, typ) + // vardef(a) // if necessary, advise liveness we are writing a new a + // *a.cap = cap // write before ptr to avoid a spill + // *a.ptr = ptr // with write barrier + // } + // *a.len = len + // // with write barriers, if needed: + // *(ptr+(len-3)) = e1 + // *(ptr+(len-2)) = e2 + // *(ptr+(len-1)) = e3 + + et := n.Type().Elem() + pt := types.NewPtr(et) + + // Evaluate slice + sn := n.Args[0] // the slice node is the first in the list + var slice, addr *ssa.Value + if inplace { + addr = s.addr(sn) + slice = s.load(n.Type(), addr) + } else { + slice = s.expr(sn) + } + + // Allocate new blocks + grow := s.f.NewBlock(ssa.BlockPlain) + assign := s.f.NewBlock(ssa.BlockPlain) + + // Decomposse input slice. + p := s.newValue1(ssa.OpSlicePtr, pt, slice) + l := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], slice) + c := s.newValue1(ssa.OpSliceCap, types.Types[types.TINT], slice) + + // Add number of new elements to length. + nargs := s.constInt(types.Types[types.TINT], int64(len(n.Args)-1)) + l = s.newValue2(s.ssaOp(ir.OADD, types.Types[types.TINT]), types.Types[types.TINT], l, nargs) + + // Decide if we need to grow + cmp := s.newValue2(s.ssaOp(ir.OLT, types.Types[types.TUINT]), types.Types[types.TBOOL], c, l) + + // Record values of ptr/len/cap before branch. + s.vars[ptrVar] = p + s.vars[lenVar] = l + if !inplace { + s.vars[capVar] = c + } + + b := s.endBlock() + b.Kind = ssa.BlockIf + b.Likely = ssa.BranchUnlikely + b.SetControl(cmp) + b.AddEdgeTo(grow) + b.AddEdgeTo(assign) + + // Call growslice + s.startBlock(grow) + taddr := s.expr(n.X) + r := s.rtcall(ir.Syms.Growslice, true, []*types.Type{n.Type()}, p, l, c, nargs, taddr) + + // Decompose output slice + p = s.newValue1(ssa.OpSlicePtr, pt, r[0]) + l = s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], r[0]) + c = s.newValue1(ssa.OpSliceCap, types.Types[types.TINT], r[0]) + + s.vars[ptrVar] = p + s.vars[lenVar] = l + s.vars[capVar] = c + if inplace { + if sn.Op() == ir.ONAME { + sn := sn.(*ir.Name) + if sn.Class != ir.PEXTERN { + // Tell liveness we're about to build a new slice + s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, sn, s.mem()) + } + } + capaddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, types.SliceCapOffset, addr) + s.store(types.Types[types.TINT], capaddr, c) + s.store(pt, addr, p) + } + + b = s.endBlock() + b.AddEdgeTo(assign) + + // assign new elements to slots + s.startBlock(assign) + p = s.variable(ptrVar, pt) // generates phi for ptr + l = s.variable(lenVar, types.Types[types.TINT]) // generates phi for len + if !inplace { + c = s.variable(capVar, types.Types[types.TINT]) // generates phi for cap + } + + if inplace { + // Update length in place. + // We have to wait until here to make sure growslice succeeded. + lenaddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, types.SliceLenOffset, addr) + s.store(types.Types[types.TINT], lenaddr, l) + } + + // Evaluate args + type argRec struct { + // if store is true, we're appending the value v. If false, we're appending the + // value at *v. + v *ssa.Value + store bool + } + args := make([]argRec, 0, len(n.Args[1:])) + for _, n := range n.Args[1:] { + if TypeOK(n.Type()) { + args = append(args, argRec{v: s.expr(n), store: true}) + } else { + v := s.addr(n) + args = append(args, argRec{v: v}) + } + } + + // Write args into slice. + oldLen := s.newValue2(s.ssaOp(ir.OSUB, types.Types[types.TINT]), types.Types[types.TINT], l, nargs) + p2 := s.newValue2(ssa.OpPtrIndex, pt, p, oldLen) + for i, arg := range args { + addr := s.newValue2(ssa.OpPtrIndex, pt, p2, s.constInt(types.Types[types.TINT], int64(i))) + if arg.store { + s.storeType(et, addr, arg.v, 0, true) + } else { + s.move(et, addr, arg.v) + } + } + + // The following deletions have no practical effect at this time + // because state.vars has been reset by the preceding state.startBlock. + // They only enforce the fact that these variables are no longer need in + // the current scope. + delete(s.vars, ptrVar) + delete(s.vars, lenVar) + if !inplace { + delete(s.vars, capVar) + } + + // make result + if inplace { + return nil + } + return s.newValue3(ssa.OpSliceMake, n.Type(), p, l, c) +} + +// minMax converts an OMIN/OMAX builtin call into SSA. +func (s *state) minMax(n *ir.CallExpr) *ssa.Value { + // The OMIN/OMAX builtin is variadic, but its semantics are + // equivalent to left-folding a binary min/max operation across the + // arguments list. + fold := func(op func(x, a *ssa.Value) *ssa.Value) *ssa.Value { + x := s.expr(n.Args[0]) + for _, arg := range n.Args[1:] { + x = op(x, s.expr(arg)) + } + return x + } + + typ := n.Type() + + if typ.IsFloat() || typ.IsString() { + // min/max semantics for floats are tricky because of NaNs and + // negative zero, so we let the runtime handle this instead. + // + // Strings are conceptually simpler, but we currently desugar + // string comparisons during walk, not ssagen. + + var name string + switch typ.Kind() { + case types.TFLOAT32: + switch n.Op() { + case ir.OMIN: + name = "fmin32" + case ir.OMAX: + name = "fmax32" + } + case types.TFLOAT64: + switch n.Op() { + case ir.OMIN: + name = "fmin64" + case ir.OMAX: + name = "fmax64" + } + case types.TSTRING: + switch n.Op() { + case ir.OMIN: + name = "strmin" + case ir.OMAX: + name = "strmax" + } + } + fn := typecheck.LookupRuntimeFunc(name) + + return fold(func(x, a *ssa.Value) *ssa.Value { + return s.rtcall(fn, true, []*types.Type{typ}, x, a)[0] + }) + } + + lt := s.ssaOp(ir.OLT, typ) + + return fold(func(x, a *ssa.Value) *ssa.Value { + switch n.Op() { + case ir.OMIN: + // a < x ? a : x + return s.ternary(s.newValue2(lt, types.Types[types.TBOOL], a, x), a, x) + case ir.OMAX: + // x < a ? a : x + return s.ternary(s.newValue2(lt, types.Types[types.TBOOL], x, a), a, x) + } + panic("unreachable") + }) +} + +// ternary emits code to evaluate cond ? x : y. +func (s *state) ternary(cond, x, y *ssa.Value) *ssa.Value { + // Note that we need a new ternaryVar each time (unlike okVar where we can + // reuse the variable) because it might have a different type every time. + ternaryVar := ssaMarker("ternary") + + bThen := s.f.NewBlock(ssa.BlockPlain) + bElse := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cond) + b.AddEdgeTo(bThen) + b.AddEdgeTo(bElse) + + s.startBlock(bThen) + s.vars[ternaryVar] = x + s.endBlock().AddEdgeTo(bEnd) + + s.startBlock(bElse) + s.vars[ternaryVar] = y + s.endBlock().AddEdgeTo(bEnd) + + s.startBlock(bEnd) + r := s.variable(ternaryVar, x.Type) + delete(s.vars, ternaryVar) + return r +} + +// condBranch evaluates the boolean expression cond and branches to yes +// if cond is true and no if cond is false. +// This function is intended to handle && and || better than just calling +// s.expr(cond) and branching on the result. +func (s *state) condBranch(cond ir.Node, yes, no *ssa.Block, likely int8) { + switch cond.Op() { + case ir.OANDAND: + cond := cond.(*ir.LogicalExpr) + mid := s.f.NewBlock(ssa.BlockPlain) + s.stmtList(cond.Init()) + s.condBranch(cond.X, mid, no, max8(likely, 0)) + s.startBlock(mid) + s.condBranch(cond.Y, yes, no, likely) + return + // Note: if likely==1, then both recursive calls pass 1. + // If likely==-1, then we don't have enough information to decide + // whether the first branch is likely or not. So we pass 0 for + // the likeliness of the first branch. + // TODO: have the frontend give us branch prediction hints for + // OANDAND and OOROR nodes (if it ever has such info). + case ir.OOROR: + cond := cond.(*ir.LogicalExpr) + mid := s.f.NewBlock(ssa.BlockPlain) + s.stmtList(cond.Init()) + s.condBranch(cond.X, yes, mid, min8(likely, 0)) + s.startBlock(mid) + s.condBranch(cond.Y, yes, no, likely) + return + // Note: if likely==-1, then both recursive calls pass -1. + // If likely==1, then we don't have enough info to decide + // the likelihood of the first branch. + case ir.ONOT: + cond := cond.(*ir.UnaryExpr) + s.stmtList(cond.Init()) + s.condBranch(cond.X, no, yes, -likely) + return + case ir.OCONVNOP: + cond := cond.(*ir.ConvExpr) + s.stmtList(cond.Init()) + s.condBranch(cond.X, yes, no, likely) + return + } + c := s.expr(cond) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(c) + b.Likely = ssa.BranchPrediction(likely) // gc and ssa both use -1/0/+1 for likeliness + b.AddEdgeTo(yes) + b.AddEdgeTo(no) +} + +type skipMask uint8 + +const ( + skipPtr skipMask = 1 << iota + skipLen + skipCap +) + +// assign does left = right. +// Right has already been evaluated to ssa, left has not. +// If deref is true, then we do left = *right instead (and right has already been nil-checked). +// If deref is true and right == nil, just do left = 0. +// skip indicates assignments (at the top level) that can be avoided. +// mayOverlap indicates whether left&right might partially overlap in memory. Default is false. +func (s *state) assign(left ir.Node, right *ssa.Value, deref bool, skip skipMask) { + s.assignWhichMayOverlap(left, right, deref, skip, false) +} +func (s *state) assignWhichMayOverlap(left ir.Node, right *ssa.Value, deref bool, skip skipMask, mayOverlap bool) { + if left.Op() == ir.ONAME && ir.IsBlank(left) { + return + } + t := left.Type() + types.CalcSize(t) + if s.canSSA(left) { + if deref { + s.Fatalf("can SSA LHS %v but not RHS %s", left, right) + } + if left.Op() == ir.ODOT { + // We're assigning to a field of an ssa-able value. + // We need to build a new structure with the new value for the + // field we're assigning and the old values for the other fields. + // For instance: + // type T struct {a, b, c int} + // var T x + // x.b = 5 + // For the x.b = 5 assignment we want to generate x = T{x.a, 5, x.c} + + // Grab information about the structure type. + left := left.(*ir.SelectorExpr) + t := left.X.Type() + nf := t.NumFields() + idx := fieldIdx(left) + + // Grab old value of structure. + old := s.expr(left.X) + + // Make new structure. + new := s.newValue0(ssa.StructMakeOp(t.NumFields()), t) + + // Add fields as args. + for i := 0; i < nf; i++ { + if i == idx { + new.AddArg(right) + } else { + new.AddArg(s.newValue1I(ssa.OpStructSelect, t.FieldType(i), int64(i), old)) + } + } + + // Recursively assign the new value we've made to the base of the dot op. + s.assign(left.X, new, false, 0) + // TODO: do we need to update named values here? + return + } + if left.Op() == ir.OINDEX && left.(*ir.IndexExpr).X.Type().IsArray() { + left := left.(*ir.IndexExpr) + s.pushLine(left.Pos()) + defer s.popLine() + // We're assigning to an element of an ssa-able array. + // a[i] = v + t := left.X.Type() + n := t.NumElem() + + i := s.expr(left.Index) // index + if n == 0 { + // The bounds check must fail. Might as well + // ignore the actual index and just use zeros. + z := s.constInt(types.Types[types.TINT], 0) + s.boundsCheck(z, z, ssa.BoundsIndex, false) + return + } + if n != 1 { + s.Fatalf("assigning to non-1-length array") + } + // Rewrite to a = [1]{v} + len := s.constInt(types.Types[types.TINT], 1) + s.boundsCheck(i, len, ssa.BoundsIndex, false) // checks i == 0 + v := s.newValue1(ssa.OpArrayMake1, t, right) + s.assign(left.X, v, false, 0) + return + } + left := left.(*ir.Name) + // Update variable assignment. + s.vars[left] = right + s.addNamedValue(left, right) + return + } + + // If this assignment clobbers an entire local variable, then emit + // OpVarDef so liveness analysis knows the variable is redefined. + if base, ok := clobberBase(left).(*ir.Name); ok && base.OnStack() && skip == 0 && t.HasPointers() { + s.vars[memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, base, s.mem(), !ir.IsAutoTmp(base)) + } + + // Left is not ssa-able. Compute its address. + addr := s.addr(left) + if ir.IsReflectHeaderDataField(left) { + // Package unsafe's documentation says storing pointers into + // reflect.SliceHeader and reflect.StringHeader's Data fields + // is valid, even though they have type uintptr (#19168). + // Mark it pointer type to signal the writebarrier pass to + // insert a write barrier. + t = types.Types[types.TUNSAFEPTR] + } + if deref { + // Treat as a mem->mem move. + if right == nil { + s.zero(t, addr) + } else { + s.moveWhichMayOverlap(t, addr, right, mayOverlap) + } + return + } + // Treat as a store. + s.storeType(t, addr, right, skip, !ir.IsAutoTmp(left)) +} + +// zeroVal returns the zero value for type t. +func (s *state) zeroVal(t *types.Type) *ssa.Value { + switch { + case t.IsInteger(): + switch t.Size() { + case 1: + return s.constInt8(t, 0) + case 2: + return s.constInt16(t, 0) + case 4: + return s.constInt32(t, 0) + case 8: + return s.constInt64(t, 0) + default: + s.Fatalf("bad sized integer type %v", t) + } + case t.IsFloat(): + switch t.Size() { + case 4: + return s.constFloat32(t, 0) + case 8: + return s.constFloat64(t, 0) + default: + s.Fatalf("bad sized float type %v", t) + } + case t.IsComplex(): + switch t.Size() { + case 8: + z := s.constFloat32(types.Types[types.TFLOAT32], 0) + return s.entryNewValue2(ssa.OpComplexMake, t, z, z) + case 16: + z := s.constFloat64(types.Types[types.TFLOAT64], 0) + return s.entryNewValue2(ssa.OpComplexMake, t, z, z) + default: + s.Fatalf("bad sized complex type %v", t) + } + + case t.IsString(): + return s.constEmptyString(t) + case t.IsPtrShaped(): + return s.constNil(t) + case t.IsBoolean(): + return s.constBool(false) + case t.IsInterface(): + return s.constInterface(t) + case t.IsSlice(): + return s.constSlice(t) + case t.IsStruct(): + n := t.NumFields() + v := s.entryNewValue0(ssa.StructMakeOp(t.NumFields()), t) + for i := 0; i < n; i++ { + v.AddArg(s.zeroVal(t.FieldType(i))) + } + return v + case t.IsArray(): + switch t.NumElem() { + case 0: + return s.entryNewValue0(ssa.OpArrayMake0, t) + case 1: + return s.entryNewValue1(ssa.OpArrayMake1, t, s.zeroVal(t.Elem())) + } + } + s.Fatalf("zero for type %v not implemented", t) + return nil +} + +type callKind int8 + +const ( + callNormal callKind = iota + callDefer + callDeferStack + callGo + callTail +) + +type sfRtCallDef struct { + rtfn *obj.LSym + rtype types.Kind +} + +var softFloatOps map[ssa.Op]sfRtCallDef + +func softfloatInit() { + // Some of these operations get transformed by sfcall. + softFloatOps = map[ssa.Op]sfRtCallDef{ + ssa.OpAdd32F: {typecheck.LookupRuntimeFunc("fadd32"), types.TFLOAT32}, + ssa.OpAdd64F: {typecheck.LookupRuntimeFunc("fadd64"), types.TFLOAT64}, + ssa.OpSub32F: {typecheck.LookupRuntimeFunc("fadd32"), types.TFLOAT32}, + ssa.OpSub64F: {typecheck.LookupRuntimeFunc("fadd64"), types.TFLOAT64}, + ssa.OpMul32F: {typecheck.LookupRuntimeFunc("fmul32"), types.TFLOAT32}, + ssa.OpMul64F: {typecheck.LookupRuntimeFunc("fmul64"), types.TFLOAT64}, + ssa.OpDiv32F: {typecheck.LookupRuntimeFunc("fdiv32"), types.TFLOAT32}, + ssa.OpDiv64F: {typecheck.LookupRuntimeFunc("fdiv64"), types.TFLOAT64}, + + ssa.OpEq64F: {typecheck.LookupRuntimeFunc("feq64"), types.TBOOL}, + ssa.OpEq32F: {typecheck.LookupRuntimeFunc("feq32"), types.TBOOL}, + ssa.OpNeq64F: {typecheck.LookupRuntimeFunc("feq64"), types.TBOOL}, + ssa.OpNeq32F: {typecheck.LookupRuntimeFunc("feq32"), types.TBOOL}, + ssa.OpLess64F: {typecheck.LookupRuntimeFunc("fgt64"), types.TBOOL}, + ssa.OpLess32F: {typecheck.LookupRuntimeFunc("fgt32"), types.TBOOL}, + ssa.OpLeq64F: {typecheck.LookupRuntimeFunc("fge64"), types.TBOOL}, + ssa.OpLeq32F: {typecheck.LookupRuntimeFunc("fge32"), types.TBOOL}, + + ssa.OpCvt32to32F: {typecheck.LookupRuntimeFunc("fint32to32"), types.TFLOAT32}, + ssa.OpCvt32Fto32: {typecheck.LookupRuntimeFunc("f32toint32"), types.TINT32}, + ssa.OpCvt64to32F: {typecheck.LookupRuntimeFunc("fint64to32"), types.TFLOAT32}, + ssa.OpCvt32Fto64: {typecheck.LookupRuntimeFunc("f32toint64"), types.TINT64}, + ssa.OpCvt64Uto32F: {typecheck.LookupRuntimeFunc("fuint64to32"), types.TFLOAT32}, + ssa.OpCvt32Fto64U: {typecheck.LookupRuntimeFunc("f32touint64"), types.TUINT64}, + ssa.OpCvt32to64F: {typecheck.LookupRuntimeFunc("fint32to64"), types.TFLOAT64}, + ssa.OpCvt64Fto32: {typecheck.LookupRuntimeFunc("f64toint32"), types.TINT32}, + ssa.OpCvt64to64F: {typecheck.LookupRuntimeFunc("fint64to64"), types.TFLOAT64}, + ssa.OpCvt64Fto64: {typecheck.LookupRuntimeFunc("f64toint64"), types.TINT64}, + ssa.OpCvt64Uto64F: {typecheck.LookupRuntimeFunc("fuint64to64"), types.TFLOAT64}, + ssa.OpCvt64Fto64U: {typecheck.LookupRuntimeFunc("f64touint64"), types.TUINT64}, + ssa.OpCvt32Fto64F: {typecheck.LookupRuntimeFunc("f32to64"), types.TFLOAT64}, + ssa.OpCvt64Fto32F: {typecheck.LookupRuntimeFunc("f64to32"), types.TFLOAT32}, + } +} + +// TODO: do not emit sfcall if operation can be optimized to constant in later +// opt phase +func (s *state) sfcall(op ssa.Op, args ...*ssa.Value) (*ssa.Value, bool) { + f2i := func(t *types.Type) *types.Type { + switch t.Kind() { + case types.TFLOAT32: + return types.Types[types.TUINT32] + case types.TFLOAT64: + return types.Types[types.TUINT64] + } + return t + } + + if callDef, ok := softFloatOps[op]; ok { + switch op { + case ssa.OpLess32F, + ssa.OpLess64F, + ssa.OpLeq32F, + ssa.OpLeq64F: + args[0], args[1] = args[1], args[0] + case ssa.OpSub32F, + ssa.OpSub64F: + args[1] = s.newValue1(s.ssaOp(ir.ONEG, types.Types[callDef.rtype]), args[1].Type, args[1]) + } + + // runtime functions take uints for floats and returns uints. + // Convert to uints so we use the right calling convention. + for i, a := range args { + if a.Type.IsFloat() { + args[i] = s.newValue1(ssa.OpCopy, f2i(a.Type), a) + } + } + + rt := types.Types[callDef.rtype] + result := s.rtcall(callDef.rtfn, true, []*types.Type{f2i(rt)}, args...)[0] + if rt.IsFloat() { + result = s.newValue1(ssa.OpCopy, rt, result) + } + if op == ssa.OpNeq32F || op == ssa.OpNeq64F { + result = s.newValue1(ssa.OpNot, result.Type, result) + } + return result, true + } + return nil, false +} + +var intrinsics map[intrinsicKey]intrinsicBuilder + +// An intrinsicBuilder converts a call node n into an ssa value that +// implements that call as an intrinsic. args is a list of arguments to the func. +type intrinsicBuilder func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value + +type intrinsicKey struct { + arch *sys.Arch + pkg string + fn string +} + +func InitTables() { + intrinsics = map[intrinsicKey]intrinsicBuilder{} + + var all []*sys.Arch + var p4 []*sys.Arch + var p8 []*sys.Arch + var lwatomics []*sys.Arch + for _, a := range &sys.Archs { + all = append(all, a) + if a.PtrSize == 4 { + p4 = append(p4, a) + } else { + p8 = append(p8, a) + } + if a.Family != sys.PPC64 { + lwatomics = append(lwatomics, a) + } + } + + // add adds the intrinsic b for pkg.fn for the given list of architectures. + add := func(pkg, fn string, b intrinsicBuilder, archs ...*sys.Arch) { + for _, a := range archs { + intrinsics[intrinsicKey{a, pkg, fn}] = b + } + } + // addF does the same as add but operates on architecture families. + addF := func(pkg, fn string, b intrinsicBuilder, archFamilies ...sys.ArchFamily) { + m := 0 + for _, f := range archFamilies { + if f >= 32 { + panic("too many architecture families") + } + m |= 1 << uint(f) + } + for _, a := range all { + if m>>uint(a.Family)&1 != 0 { + intrinsics[intrinsicKey{a, pkg, fn}] = b + } + } + } + // alias defines pkg.fn = pkg2.fn2 for all architectures in archs for which pkg2.fn2 exists. + alias := func(pkg, fn, pkg2, fn2 string, archs ...*sys.Arch) { + aliased := false + for _, a := range archs { + if b, ok := intrinsics[intrinsicKey{a, pkg2, fn2}]; ok { + intrinsics[intrinsicKey{a, pkg, fn}] = b + aliased = true + } + } + if !aliased { + panic(fmt.Sprintf("attempted to alias undefined intrinsic: %s.%s", pkg, fn)) + } + } + + /******** runtime ********/ + if !base.Flag.Cfg.Instrumenting { + add("runtime", "slicebytetostringtmp", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + // Compiler frontend optimizations emit OBYTES2STRTMP nodes + // for the backend instead of slicebytetostringtmp calls + // when not instrumenting. + return s.newValue2(ssa.OpStringMake, n.Type(), args[0], args[1]) + }, + all...) + } + addF("runtime/internal/math", "MulUintptr", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if s.config.PtrSize == 4 { + return s.newValue2(ssa.OpMul32uover, types.NewTuple(types.Types[types.TUINT], types.Types[types.TUINT]), args[0], args[1]) + } + return s.newValue2(ssa.OpMul64uover, types.NewTuple(types.Types[types.TUINT], types.Types[types.TUINT]), args[0], args[1]) + }, + sys.AMD64, sys.I386, sys.Loong64, sys.MIPS64, sys.RISCV64, sys.ARM64) + alias("runtime", "mulUintptr", "runtime/internal/math", "MulUintptr", all...) + add("runtime", "KeepAlive", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + data := s.newValue1(ssa.OpIData, s.f.Config.Types.BytePtr, args[0]) + s.vars[memVar] = s.newValue2(ssa.OpKeepAlive, types.TypeMem, data, s.mem()) + return nil + }, + all...) + add("runtime", "getclosureptr", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue0(ssa.OpGetClosurePtr, s.f.Config.Types.Uintptr) + }, + all...) + + add("runtime", "getcallerpc", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue0(ssa.OpGetCallerPC, s.f.Config.Types.Uintptr) + }, + all...) + + add("runtime", "getcallersp", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpGetCallerSP, s.f.Config.Types.Uintptr, s.mem()) + }, + all...) + + addF("runtime", "publicationBarrier", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue1(ssa.OpPubBarrier, types.TypeMem, s.mem()) + return nil + }, + sys.ARM64, sys.PPC64) + + brev_arch := []sys.ArchFamily{sys.AMD64, sys.I386, sys.ARM64, sys.ARM, sys.S390X} + if buildcfg.GOPPC64 >= 10 { + // Use only on Power10 as the new byte reverse instructions that Power10 provide + // make it worthwhile as an intrinsic + brev_arch = append(brev_arch, sys.PPC64) + } + /******** runtime/internal/sys ********/ + addF("runtime/internal/sys", "Bswap32", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBswap32, types.Types[types.TUINT32], args[0]) + }, + brev_arch...) + addF("runtime/internal/sys", "Bswap64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBswap64, types.Types[types.TUINT64], args[0]) + }, + brev_arch...) + + /****** Prefetch ******/ + makePrefetchFunc := func(op ssa.Op) func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue2(op, types.TypeMem, args[0], s.mem()) + return nil + } + } + + // Make Prefetch intrinsics for supported platforms + // On the unsupported platforms stub function will be eliminated + addF("runtime/internal/sys", "Prefetch", makePrefetchFunc(ssa.OpPrefetchCache), + sys.AMD64, sys.ARM64, sys.PPC64) + addF("runtime/internal/sys", "PrefetchStreamed", makePrefetchFunc(ssa.OpPrefetchCacheStreamed), + sys.AMD64, sys.ARM64, sys.PPC64) + + /******** runtime/internal/atomic ********/ + addF("runtime/internal/atomic", "Load", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue2(ssa.OpAtomicLoad32, types.NewTuple(types.Types[types.TUINT32], types.TypeMem), args[0], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT32], v) + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Load8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue2(ssa.OpAtomicLoad8, types.NewTuple(types.Types[types.TUINT8], types.TypeMem), args[0], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT8], v) + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Load64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue2(ssa.OpAtomicLoad64, types.NewTuple(types.Types[types.TUINT64], types.TypeMem), args[0], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT64], v) + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "LoadAcq", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue2(ssa.OpAtomicLoadAcq32, types.NewTuple(types.Types[types.TUINT32], types.TypeMem), args[0], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT32], v) + }, + sys.PPC64, sys.S390X) + addF("runtime/internal/atomic", "LoadAcq64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue2(ssa.OpAtomicLoadAcq64, types.NewTuple(types.Types[types.TUINT64], types.TypeMem), args[0], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT64], v) + }, + sys.PPC64) + addF("runtime/internal/atomic", "Loadp", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue2(ssa.OpAtomicLoadPtr, types.NewTuple(s.f.Config.Types.BytePtr, types.TypeMem), args[0], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, s.f.Config.Types.BytePtr, v) + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + + addF("runtime/internal/atomic", "Store", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicStore32, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Store8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicStore8, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Store64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicStore64, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "StorepNoWB", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicStorePtrNoWB, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "StoreRel", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicStoreRel32, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.PPC64, sys.S390X) + addF("runtime/internal/atomic", "StoreRel64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicStoreRel64, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.PPC64) + + addF("runtime/internal/atomic", "Xchg", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue3(ssa.OpAtomicExchange32, types.NewTuple(types.Types[types.TUINT32], types.TypeMem), args[0], args[1], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT32], v) + }, + sys.AMD64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Xchg64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue3(ssa.OpAtomicExchange64, types.NewTuple(types.Types[types.TUINT64], types.TypeMem), args[0], args[1], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT64], v) + }, + sys.AMD64, sys.Loong64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + + type atomicOpEmitter func(s *state, n *ir.CallExpr, args []*ssa.Value, op ssa.Op, typ types.Kind) + + makeAtomicGuardedIntrinsicARM64 := func(op0, op1 ssa.Op, typ, rtyp types.Kind, emit atomicOpEmitter) intrinsicBuilder { + + return func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + // Target Atomic feature is identified by dynamic detection + addr := s.entryNewValue1A(ssa.OpAddr, types.Types[types.TBOOL].PtrTo(), ir.Syms.ARM64HasATOMICS, s.sb) + v := s.load(types.Types[types.TBOOL], addr) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(v) + bTrue := s.f.NewBlock(ssa.BlockPlain) + bFalse := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bTrue) + b.AddEdgeTo(bFalse) + b.Likely = ssa.BranchLikely + + // We have atomic instructions - use it directly. + s.startBlock(bTrue) + emit(s, n, args, op1, typ) + s.endBlock().AddEdgeTo(bEnd) + + // Use original instruction sequence. + s.startBlock(bFalse) + emit(s, n, args, op0, typ) + s.endBlock().AddEdgeTo(bEnd) + + // Merge results. + s.startBlock(bEnd) + if rtyp == types.TNIL { + return nil + } else { + return s.variable(n, types.Types[rtyp]) + } + } + } + + atomicXchgXaddEmitterARM64 := func(s *state, n *ir.CallExpr, args []*ssa.Value, op ssa.Op, typ types.Kind) { + v := s.newValue3(op, types.NewTuple(types.Types[typ], types.TypeMem), args[0], args[1], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + s.vars[n] = s.newValue1(ssa.OpSelect0, types.Types[typ], v) + } + addF("runtime/internal/atomic", "Xchg", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicExchange32, ssa.OpAtomicExchange32Variant, types.TUINT32, types.TUINT32, atomicXchgXaddEmitterARM64), + sys.ARM64) + addF("runtime/internal/atomic", "Xchg64", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicExchange64, ssa.OpAtomicExchange64Variant, types.TUINT64, types.TUINT64, atomicXchgXaddEmitterARM64), + sys.ARM64) + + addF("runtime/internal/atomic", "Xadd", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue3(ssa.OpAtomicAdd32, types.NewTuple(types.Types[types.TUINT32], types.TypeMem), args[0], args[1], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT32], v) + }, + sys.AMD64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Xadd64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue3(ssa.OpAtomicAdd64, types.NewTuple(types.Types[types.TUINT64], types.TypeMem), args[0], args[1], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TUINT64], v) + }, + sys.AMD64, sys.Loong64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + + addF("runtime/internal/atomic", "Xadd", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicAdd32, ssa.OpAtomicAdd32Variant, types.TUINT32, types.TUINT32, atomicXchgXaddEmitterARM64), + sys.ARM64) + addF("runtime/internal/atomic", "Xadd64", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicAdd64, ssa.OpAtomicAdd64Variant, types.TUINT64, types.TUINT64, atomicXchgXaddEmitterARM64), + sys.ARM64) + + addF("runtime/internal/atomic", "Cas", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue4(ssa.OpAtomicCompareAndSwap32, types.NewTuple(types.Types[types.TBOOL], types.TypeMem), args[0], args[1], args[2], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TBOOL], v) + }, + sys.AMD64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Cas64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue4(ssa.OpAtomicCompareAndSwap64, types.NewTuple(types.Types[types.TBOOL], types.TypeMem), args[0], args[1], args[2], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TBOOL], v) + }, + sys.AMD64, sys.Loong64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "CasRel", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + v := s.newValue4(ssa.OpAtomicCompareAndSwap32, types.NewTuple(types.Types[types.TBOOL], types.TypeMem), args[0], args[1], args[2], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + return s.newValue1(ssa.OpSelect0, types.Types[types.TBOOL], v) + }, + sys.PPC64) + + atomicCasEmitterARM64 := func(s *state, n *ir.CallExpr, args []*ssa.Value, op ssa.Op, typ types.Kind) { + v := s.newValue4(op, types.NewTuple(types.Types[types.TBOOL], types.TypeMem), args[0], args[1], args[2], s.mem()) + s.vars[memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v) + s.vars[n] = s.newValue1(ssa.OpSelect0, types.Types[typ], v) + } + + addF("runtime/internal/atomic", "Cas", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicCompareAndSwap32, ssa.OpAtomicCompareAndSwap32Variant, types.TUINT32, types.TBOOL, atomicCasEmitterARM64), + sys.ARM64) + addF("runtime/internal/atomic", "Cas64", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicCompareAndSwap64, ssa.OpAtomicCompareAndSwap64Variant, types.TUINT64, types.TBOOL, atomicCasEmitterARM64), + sys.ARM64) + + addF("runtime/internal/atomic", "And8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicAnd8, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "And", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicAnd32, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Or8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicOr8, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("runtime/internal/atomic", "Or", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + s.vars[memVar] = s.newValue3(ssa.OpAtomicOr32, types.TypeMem, args[0], args[1], s.mem()) + return nil + }, + sys.AMD64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X) + + atomicAndOrEmitterARM64 := func(s *state, n *ir.CallExpr, args []*ssa.Value, op ssa.Op, typ types.Kind) { + s.vars[memVar] = s.newValue3(op, types.TypeMem, args[0], args[1], s.mem()) + } + + addF("runtime/internal/atomic", "And8", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicAnd8, ssa.OpAtomicAnd8Variant, types.TNIL, types.TNIL, atomicAndOrEmitterARM64), + sys.ARM64) + addF("runtime/internal/atomic", "And", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicAnd32, ssa.OpAtomicAnd32Variant, types.TNIL, types.TNIL, atomicAndOrEmitterARM64), + sys.ARM64) + addF("runtime/internal/atomic", "Or8", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicOr8, ssa.OpAtomicOr8Variant, types.TNIL, types.TNIL, atomicAndOrEmitterARM64), + sys.ARM64) + addF("runtime/internal/atomic", "Or", + makeAtomicGuardedIntrinsicARM64(ssa.OpAtomicOr32, ssa.OpAtomicOr32Variant, types.TNIL, types.TNIL, atomicAndOrEmitterARM64), + sys.ARM64) + + // Aliases for atomic load operations + alias("runtime/internal/atomic", "Loadint32", "runtime/internal/atomic", "Load", all...) + alias("runtime/internal/atomic", "Loadint64", "runtime/internal/atomic", "Load64", all...) + alias("runtime/internal/atomic", "Loaduintptr", "runtime/internal/atomic", "Load", p4...) + alias("runtime/internal/atomic", "Loaduintptr", "runtime/internal/atomic", "Load64", p8...) + alias("runtime/internal/atomic", "Loaduint", "runtime/internal/atomic", "Load", p4...) + alias("runtime/internal/atomic", "Loaduint", "runtime/internal/atomic", "Load64", p8...) + alias("runtime/internal/atomic", "LoadAcq", "runtime/internal/atomic", "Load", lwatomics...) + alias("runtime/internal/atomic", "LoadAcq64", "runtime/internal/atomic", "Load64", lwatomics...) + alias("runtime/internal/atomic", "LoadAcquintptr", "runtime/internal/atomic", "LoadAcq", p4...) + alias("sync", "runtime_LoadAcquintptr", "runtime/internal/atomic", "LoadAcq", p4...) // linknamed + alias("runtime/internal/atomic", "LoadAcquintptr", "runtime/internal/atomic", "LoadAcq64", p8...) + alias("sync", "runtime_LoadAcquintptr", "runtime/internal/atomic", "LoadAcq64", p8...) // linknamed + + // Aliases for atomic store operations + alias("runtime/internal/atomic", "Storeint32", "runtime/internal/atomic", "Store", all...) + alias("runtime/internal/atomic", "Storeint64", "runtime/internal/atomic", "Store64", all...) + alias("runtime/internal/atomic", "Storeuintptr", "runtime/internal/atomic", "Store", p4...) + alias("runtime/internal/atomic", "Storeuintptr", "runtime/internal/atomic", "Store64", p8...) + alias("runtime/internal/atomic", "StoreRel", "runtime/internal/atomic", "Store", lwatomics...) + alias("runtime/internal/atomic", "StoreRel64", "runtime/internal/atomic", "Store64", lwatomics...) + alias("runtime/internal/atomic", "StoreReluintptr", "runtime/internal/atomic", "StoreRel", p4...) + alias("sync", "runtime_StoreReluintptr", "runtime/internal/atomic", "StoreRel", p4...) // linknamed + alias("runtime/internal/atomic", "StoreReluintptr", "runtime/internal/atomic", "StoreRel64", p8...) + alias("sync", "runtime_StoreReluintptr", "runtime/internal/atomic", "StoreRel64", p8...) // linknamed + + // Aliases for atomic swap operations + alias("runtime/internal/atomic", "Xchgint32", "runtime/internal/atomic", "Xchg", all...) + alias("runtime/internal/atomic", "Xchgint64", "runtime/internal/atomic", "Xchg64", all...) + alias("runtime/internal/atomic", "Xchguintptr", "runtime/internal/atomic", "Xchg", p4...) + alias("runtime/internal/atomic", "Xchguintptr", "runtime/internal/atomic", "Xchg64", p8...) + + // Aliases for atomic add operations + alias("runtime/internal/atomic", "Xaddint32", "runtime/internal/atomic", "Xadd", all...) + alias("runtime/internal/atomic", "Xaddint64", "runtime/internal/atomic", "Xadd64", all...) + alias("runtime/internal/atomic", "Xadduintptr", "runtime/internal/atomic", "Xadd", p4...) + alias("runtime/internal/atomic", "Xadduintptr", "runtime/internal/atomic", "Xadd64", p8...) + + // Aliases for atomic CAS operations + alias("runtime/internal/atomic", "Casint32", "runtime/internal/atomic", "Cas", all...) + alias("runtime/internal/atomic", "Casint64", "runtime/internal/atomic", "Cas64", all...) + alias("runtime/internal/atomic", "Casuintptr", "runtime/internal/atomic", "Cas", p4...) + alias("runtime/internal/atomic", "Casuintptr", "runtime/internal/atomic", "Cas64", p8...) + alias("runtime/internal/atomic", "Casp1", "runtime/internal/atomic", "Cas", p4...) + alias("runtime/internal/atomic", "Casp1", "runtime/internal/atomic", "Cas64", p8...) + alias("runtime/internal/atomic", "CasRel", "runtime/internal/atomic", "Cas", lwatomics...) + + /******** math ********/ + addF("math", "sqrt", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpSqrt, types.Types[types.TFLOAT64], args[0]) + }, + sys.I386, sys.AMD64, sys.ARM, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X, sys.Wasm) + addF("math", "Trunc", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpTrunc, types.Types[types.TFLOAT64], args[0]) + }, + sys.ARM64, sys.PPC64, sys.S390X, sys.Wasm) + addF("math", "Ceil", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpCeil, types.Types[types.TFLOAT64], args[0]) + }, + sys.ARM64, sys.PPC64, sys.S390X, sys.Wasm) + addF("math", "Floor", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpFloor, types.Types[types.TFLOAT64], args[0]) + }, + sys.ARM64, sys.PPC64, sys.S390X, sys.Wasm) + addF("math", "Round", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpRound, types.Types[types.TFLOAT64], args[0]) + }, + sys.ARM64, sys.PPC64, sys.S390X) + addF("math", "RoundToEven", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpRoundToEven, types.Types[types.TFLOAT64], args[0]) + }, + sys.ARM64, sys.S390X, sys.Wasm) + addF("math", "Abs", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpAbs, types.Types[types.TFLOAT64], args[0]) + }, + sys.ARM64, sys.ARM, sys.PPC64, sys.RISCV64, sys.Wasm, sys.MIPS, sys.MIPS64) + addF("math", "Copysign", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpCopysign, types.Types[types.TFLOAT64], args[0], args[1]) + }, + sys.PPC64, sys.RISCV64, sys.Wasm) + addF("math", "FMA", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue3(ssa.OpFMA, types.Types[types.TFLOAT64], args[0], args[1], args[2]) + }, + sys.ARM64, sys.PPC64, sys.RISCV64, sys.S390X) + addF("math", "FMA", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if !s.config.UseFMA { + s.vars[n] = s.callResult(n, callNormal) // types.Types[TFLOAT64] + return s.variable(n, types.Types[types.TFLOAT64]) + } + + if buildcfg.GOAMD64 >= 3 { + return s.newValue3(ssa.OpFMA, types.Types[types.TFLOAT64], args[0], args[1], args[2]) + } + + v := s.entryNewValue0A(ssa.OpHasCPUFeature, types.Types[types.TBOOL], ir.Syms.X86HasFMA) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(v) + bTrue := s.f.NewBlock(ssa.BlockPlain) + bFalse := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bTrue) + b.AddEdgeTo(bFalse) + b.Likely = ssa.BranchLikely // >= haswell cpus are common + + // We have the intrinsic - use it directly. + s.startBlock(bTrue) + s.vars[n] = s.newValue3(ssa.OpFMA, types.Types[types.TFLOAT64], args[0], args[1], args[2]) + s.endBlock().AddEdgeTo(bEnd) + + // Call the pure Go version. + s.startBlock(bFalse) + s.vars[n] = s.callResult(n, callNormal) // types.Types[TFLOAT64] + s.endBlock().AddEdgeTo(bEnd) + + // Merge results. + s.startBlock(bEnd) + return s.variable(n, types.Types[types.TFLOAT64]) + }, + sys.AMD64) + addF("math", "FMA", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if !s.config.UseFMA { + s.vars[n] = s.callResult(n, callNormal) // types.Types[TFLOAT64] + return s.variable(n, types.Types[types.TFLOAT64]) + } + addr := s.entryNewValue1A(ssa.OpAddr, types.Types[types.TBOOL].PtrTo(), ir.Syms.ARMHasVFPv4, s.sb) + v := s.load(types.Types[types.TBOOL], addr) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(v) + bTrue := s.f.NewBlock(ssa.BlockPlain) + bFalse := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bTrue) + b.AddEdgeTo(bFalse) + b.Likely = ssa.BranchLikely + + // We have the intrinsic - use it directly. + s.startBlock(bTrue) + s.vars[n] = s.newValue3(ssa.OpFMA, types.Types[types.TFLOAT64], args[0], args[1], args[2]) + s.endBlock().AddEdgeTo(bEnd) + + // Call the pure Go version. + s.startBlock(bFalse) + s.vars[n] = s.callResult(n, callNormal) // types.Types[TFLOAT64] + s.endBlock().AddEdgeTo(bEnd) + + // Merge results. + s.startBlock(bEnd) + return s.variable(n, types.Types[types.TFLOAT64]) + }, + sys.ARM) + + makeRoundAMD64 := func(op ssa.Op) func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if buildcfg.GOAMD64 >= 2 { + return s.newValue1(op, types.Types[types.TFLOAT64], args[0]) + } + + v := s.entryNewValue0A(ssa.OpHasCPUFeature, types.Types[types.TBOOL], ir.Syms.X86HasSSE41) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(v) + bTrue := s.f.NewBlock(ssa.BlockPlain) + bFalse := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bTrue) + b.AddEdgeTo(bFalse) + b.Likely = ssa.BranchLikely // most machines have sse4.1 nowadays + + // We have the intrinsic - use it directly. + s.startBlock(bTrue) + s.vars[n] = s.newValue1(op, types.Types[types.TFLOAT64], args[0]) + s.endBlock().AddEdgeTo(bEnd) + + // Call the pure Go version. + s.startBlock(bFalse) + s.vars[n] = s.callResult(n, callNormal) // types.Types[TFLOAT64] + s.endBlock().AddEdgeTo(bEnd) + + // Merge results. + s.startBlock(bEnd) + return s.variable(n, types.Types[types.TFLOAT64]) + } + } + addF("math", "RoundToEven", + makeRoundAMD64(ssa.OpRoundToEven), + sys.AMD64) + addF("math", "Floor", + makeRoundAMD64(ssa.OpFloor), + sys.AMD64) + addF("math", "Ceil", + makeRoundAMD64(ssa.OpCeil), + sys.AMD64) + addF("math", "Trunc", + makeRoundAMD64(ssa.OpTrunc), + sys.AMD64) + + /******** math/bits ********/ + addF("math/bits", "TrailingZeros64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpCtz64, types.Types[types.TINT], args[0]) + }, + sys.AMD64, sys.I386, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm) + addF("math/bits", "TrailingZeros32", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpCtz32, types.Types[types.TINT], args[0]) + }, + sys.AMD64, sys.I386, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm) + addF("math/bits", "TrailingZeros16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + x := s.newValue1(ssa.OpZeroExt16to32, types.Types[types.TUINT32], args[0]) + c := s.constInt32(types.Types[types.TUINT32], 1<<16) + y := s.newValue2(ssa.OpOr32, types.Types[types.TUINT32], x, c) + return s.newValue1(ssa.OpCtz32, types.Types[types.TINT], y) + }, + sys.MIPS) + addF("math/bits", "TrailingZeros16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpCtz16, types.Types[types.TINT], args[0]) + }, + sys.AMD64, sys.I386, sys.ARM, sys.ARM64, sys.Wasm) + addF("math/bits", "TrailingZeros16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + x := s.newValue1(ssa.OpZeroExt16to64, types.Types[types.TUINT64], args[0]) + c := s.constInt64(types.Types[types.TUINT64], 1<<16) + y := s.newValue2(ssa.OpOr64, types.Types[types.TUINT64], x, c) + return s.newValue1(ssa.OpCtz64, types.Types[types.TINT], y) + }, + sys.S390X, sys.PPC64) + addF("math/bits", "TrailingZeros8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + x := s.newValue1(ssa.OpZeroExt8to32, types.Types[types.TUINT32], args[0]) + c := s.constInt32(types.Types[types.TUINT32], 1<<8) + y := s.newValue2(ssa.OpOr32, types.Types[types.TUINT32], x, c) + return s.newValue1(ssa.OpCtz32, types.Types[types.TINT], y) + }, + sys.MIPS) + addF("math/bits", "TrailingZeros8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpCtz8, types.Types[types.TINT], args[0]) + }, + sys.AMD64, sys.I386, sys.ARM, sys.ARM64, sys.Wasm) + addF("math/bits", "TrailingZeros8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + x := s.newValue1(ssa.OpZeroExt8to64, types.Types[types.TUINT64], args[0]) + c := s.constInt64(types.Types[types.TUINT64], 1<<8) + y := s.newValue2(ssa.OpOr64, types.Types[types.TUINT64], x, c) + return s.newValue1(ssa.OpCtz64, types.Types[types.TINT], y) + }, + sys.S390X) + alias("math/bits", "ReverseBytes64", "runtime/internal/sys", "Bswap64", all...) + alias("math/bits", "ReverseBytes32", "runtime/internal/sys", "Bswap32", all...) + // ReverseBytes inlines correctly, no need to intrinsify it. + // Nothing special is needed for targets where ReverseBytes16 lowers to a rotate + // On Power10, 16-bit rotate is not available so use BRH instruction + if buildcfg.GOPPC64 >= 10 { + addF("math/bits", "ReverseBytes16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBswap16, types.Types[types.TUINT], args[0]) + }, + sys.PPC64) + } + + addF("math/bits", "Len64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitLen64, types.Types[types.TINT], args[0]) + }, + sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm) + addF("math/bits", "Len32", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitLen32, types.Types[types.TINT], args[0]) + }, + sys.AMD64, sys.ARM64, sys.PPC64) + addF("math/bits", "Len32", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if s.config.PtrSize == 4 { + return s.newValue1(ssa.OpBitLen32, types.Types[types.TINT], args[0]) + } + x := s.newValue1(ssa.OpZeroExt32to64, types.Types[types.TUINT64], args[0]) + return s.newValue1(ssa.OpBitLen64, types.Types[types.TINT], x) + }, + sys.ARM, sys.S390X, sys.MIPS, sys.Wasm) + addF("math/bits", "Len16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if s.config.PtrSize == 4 { + x := s.newValue1(ssa.OpZeroExt16to32, types.Types[types.TUINT32], args[0]) + return s.newValue1(ssa.OpBitLen32, types.Types[types.TINT], x) + } + x := s.newValue1(ssa.OpZeroExt16to64, types.Types[types.TUINT64], args[0]) + return s.newValue1(ssa.OpBitLen64, types.Types[types.TINT], x) + }, + sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm) + addF("math/bits", "Len16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitLen16, types.Types[types.TINT], args[0]) + }, + sys.AMD64) + addF("math/bits", "Len8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if s.config.PtrSize == 4 { + x := s.newValue1(ssa.OpZeroExt8to32, types.Types[types.TUINT32], args[0]) + return s.newValue1(ssa.OpBitLen32, types.Types[types.TINT], x) + } + x := s.newValue1(ssa.OpZeroExt8to64, types.Types[types.TUINT64], args[0]) + return s.newValue1(ssa.OpBitLen64, types.Types[types.TINT], x) + }, + sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm) + addF("math/bits", "Len8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitLen8, types.Types[types.TINT], args[0]) + }, + sys.AMD64) + addF("math/bits", "Len", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if s.config.PtrSize == 4 { + return s.newValue1(ssa.OpBitLen32, types.Types[types.TINT], args[0]) + } + return s.newValue1(ssa.OpBitLen64, types.Types[types.TINT], args[0]) + }, + sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm) + // LeadingZeros is handled because it trivially calls Len. + addF("math/bits", "Reverse64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitRev64, types.Types[types.TINT], args[0]) + }, + sys.ARM64) + addF("math/bits", "Reverse32", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitRev32, types.Types[types.TINT], args[0]) + }, + sys.ARM64) + addF("math/bits", "Reverse16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitRev16, types.Types[types.TINT], args[0]) + }, + sys.ARM64) + addF("math/bits", "Reverse8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitRev8, types.Types[types.TINT], args[0]) + }, + sys.ARM64) + addF("math/bits", "Reverse", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpBitRev64, types.Types[types.TINT], args[0]) + }, + sys.ARM64) + addF("math/bits", "RotateLeft8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpRotateLeft8, types.Types[types.TUINT8], args[0], args[1]) + }, + sys.AMD64) + addF("math/bits", "RotateLeft16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpRotateLeft16, types.Types[types.TUINT16], args[0], args[1]) + }, + sys.AMD64) + addF("math/bits", "RotateLeft32", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpRotateLeft32, types.Types[types.TUINT32], args[0], args[1]) + }, + sys.AMD64, sys.ARM, sys.ARM64, sys.S390X, sys.PPC64, sys.Wasm, sys.Loong64) + addF("math/bits", "RotateLeft64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpRotateLeft64, types.Types[types.TUINT64], args[0], args[1]) + }, + sys.AMD64, sys.ARM64, sys.S390X, sys.PPC64, sys.Wasm, sys.Loong64) + alias("math/bits", "RotateLeft", "math/bits", "RotateLeft64", p8...) + + makeOnesCountAMD64 := func(op ssa.Op) func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + if buildcfg.GOAMD64 >= 2 { + return s.newValue1(op, types.Types[types.TINT], args[0]) + } + + v := s.entryNewValue0A(ssa.OpHasCPUFeature, types.Types[types.TBOOL], ir.Syms.X86HasPOPCNT) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(v) + bTrue := s.f.NewBlock(ssa.BlockPlain) + bFalse := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bTrue) + b.AddEdgeTo(bFalse) + b.Likely = ssa.BranchLikely // most machines have popcnt nowadays + + // We have the intrinsic - use it directly. + s.startBlock(bTrue) + s.vars[n] = s.newValue1(op, types.Types[types.TINT], args[0]) + s.endBlock().AddEdgeTo(bEnd) + + // Call the pure Go version. + s.startBlock(bFalse) + s.vars[n] = s.callResult(n, callNormal) // types.Types[TINT] + s.endBlock().AddEdgeTo(bEnd) + + // Merge results. + s.startBlock(bEnd) + return s.variable(n, types.Types[types.TINT]) + } + } + addF("math/bits", "OnesCount64", + makeOnesCountAMD64(ssa.OpPopCount64), + sys.AMD64) + addF("math/bits", "OnesCount64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpPopCount64, types.Types[types.TINT], args[0]) + }, + sys.PPC64, sys.ARM64, sys.S390X, sys.Wasm) + addF("math/bits", "OnesCount32", + makeOnesCountAMD64(ssa.OpPopCount32), + sys.AMD64) + addF("math/bits", "OnesCount32", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpPopCount32, types.Types[types.TINT], args[0]) + }, + sys.PPC64, sys.ARM64, sys.S390X, sys.Wasm) + addF("math/bits", "OnesCount16", + makeOnesCountAMD64(ssa.OpPopCount16), + sys.AMD64) + addF("math/bits", "OnesCount16", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpPopCount16, types.Types[types.TINT], args[0]) + }, + sys.ARM64, sys.S390X, sys.PPC64, sys.Wasm) + addF("math/bits", "OnesCount8", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue1(ssa.OpPopCount8, types.Types[types.TINT], args[0]) + }, + sys.S390X, sys.PPC64, sys.Wasm) + addF("math/bits", "OnesCount", + makeOnesCountAMD64(ssa.OpPopCount64), + sys.AMD64) + addF("math/bits", "Mul64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpMul64uhilo, types.NewTuple(types.Types[types.TUINT64], types.Types[types.TUINT64]), args[0], args[1]) + }, + sys.AMD64, sys.ARM64, sys.PPC64, sys.S390X, sys.MIPS64, sys.RISCV64, sys.Loong64) + alias("math/bits", "Mul", "math/bits", "Mul64", p8...) + alias("runtime/internal/math", "Mul64", "math/bits", "Mul64", p8...) + addF("math/bits", "Add64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue3(ssa.OpAdd64carry, types.NewTuple(types.Types[types.TUINT64], types.Types[types.TUINT64]), args[0], args[1], args[2]) + }, + sys.AMD64, sys.ARM64, sys.PPC64, sys.S390X, sys.RISCV64, sys.Loong64) + alias("math/bits", "Add", "math/bits", "Add64", p8...) + addF("math/bits", "Sub64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + return s.newValue3(ssa.OpSub64borrow, types.NewTuple(types.Types[types.TUINT64], types.Types[types.TUINT64]), args[0], args[1], args[2]) + }, + sys.AMD64, sys.ARM64, sys.PPC64, sys.S390X, sys.RISCV64, sys.Loong64) + alias("math/bits", "Sub", "math/bits", "Sub64", p8...) + addF("math/bits", "Div64", + func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value { + // check for divide-by-zero/overflow and panic with appropriate message + cmpZero := s.newValue2(s.ssaOp(ir.ONE, types.Types[types.TUINT64]), types.Types[types.TBOOL], args[2], s.zeroVal(types.Types[types.TUINT64])) + s.check(cmpZero, ir.Syms.Panicdivide) + cmpOverflow := s.newValue2(s.ssaOp(ir.OLT, types.Types[types.TUINT64]), types.Types[types.TBOOL], args[0], args[2]) + s.check(cmpOverflow, ir.Syms.Panicoverflow) + return s.newValue3(ssa.OpDiv128u, types.NewTuple(types.Types[types.TUINT64], types.Types[types.TUINT64]), args[0], args[1], args[2]) + }, + sys.AMD64) + alias("math/bits", "Div", "math/bits", "Div64", sys.ArchAMD64) + + alias("runtime/internal/sys", "TrailingZeros8", "math/bits", "TrailingZeros8", all...) + alias("runtime/internal/sys", "TrailingZeros32", "math/bits", "TrailingZeros32", all...) + alias("runtime/internal/sys", "TrailingZeros64", "math/bits", "TrailingZeros64", all...) + alias("runtime/internal/sys", "Len8", "math/bits", "Len8", all...) + alias("runtime/internal/sys", "Len64", "math/bits", "Len64", all...) + alias("runtime/internal/sys", "OnesCount64", "math/bits", "OnesCount64", all...) + + /******** sync/atomic ********/ + + // Note: these are disabled by flag_race in findIntrinsic below. + alias("sync/atomic", "LoadInt32", "runtime/internal/atomic", "Load", all...) + alias("sync/atomic", "LoadInt64", "runtime/internal/atomic", "Load64", all...) + alias("sync/atomic", "LoadPointer", "runtime/internal/atomic", "Loadp", all...) + alias("sync/atomic", "LoadUint32", "runtime/internal/atomic", "Load", all...) + alias("sync/atomic", "LoadUint64", "runtime/internal/atomic", "Load64", all...) + alias("sync/atomic", "LoadUintptr", "runtime/internal/atomic", "Load", p4...) + alias("sync/atomic", "LoadUintptr", "runtime/internal/atomic", "Load64", p8...) + + alias("sync/atomic", "StoreInt32", "runtime/internal/atomic", "Store", all...) + alias("sync/atomic", "StoreInt64", "runtime/internal/atomic", "Store64", all...) + // Note: not StorePointer, that needs a write barrier. Same below for {CompareAnd}Swap. + alias("sync/atomic", "StoreUint32", "runtime/internal/atomic", "Store", all...) + alias("sync/atomic", "StoreUint64", "runtime/internal/atomic", "Store64", all...) + alias("sync/atomic", "StoreUintptr", "runtime/internal/atomic", "Store", p4...) + alias("sync/atomic", "StoreUintptr", "runtime/internal/atomic", "Store64", p8...) + + alias("sync/atomic", "SwapInt32", "runtime/internal/atomic", "Xchg", all...) + alias("sync/atomic", "SwapInt64", "runtime/internal/atomic", "Xchg64", all...) + alias("sync/atomic", "SwapUint32", "runtime/internal/atomic", "Xchg", all...) + alias("sync/atomic", "SwapUint64", "runtime/internal/atomic", "Xchg64", all...) + alias("sync/atomic", "SwapUintptr", "runtime/internal/atomic", "Xchg", p4...) + alias("sync/atomic", "SwapUintptr", "runtime/internal/atomic", "Xchg64", p8...) + + alias("sync/atomic", "CompareAndSwapInt32", "runtime/internal/atomic", "Cas", all...) + alias("sync/atomic", "CompareAndSwapInt64", "runtime/internal/atomic", "Cas64", all...) + alias("sync/atomic", "CompareAndSwapUint32", "runtime/internal/atomic", "Cas", all...) + alias("sync/atomic", "CompareAndSwapUint64", "runtime/internal/atomic", "Cas64", all...) + alias("sync/atomic", "CompareAndSwapUintptr", "runtime/internal/atomic", "Cas", p4...) + alias("sync/atomic", "CompareAndSwapUintptr", "runtime/internal/atomic", "Cas64", p8...) + + alias("sync/atomic", "AddInt32", "runtime/internal/atomic", "Xadd", all...) + alias("sync/atomic", "AddInt64", "runtime/internal/atomic", "Xadd64", all...) + alias("sync/atomic", "AddUint32", "runtime/internal/atomic", "Xadd", all...) + alias("sync/atomic", "AddUint64", "runtime/internal/atomic", "Xadd64", all...) + alias("sync/atomic", "AddUintptr", "runtime/internal/atomic", "Xadd", p4...) + alias("sync/atomic", "AddUintptr", "runtime/internal/atomic", "Xadd64", p8...) + + /******** math/big ********/ + alias("math/big", "mulWW", "math/bits", "Mul64", p8...) +} + +// findIntrinsic returns a function which builds the SSA equivalent of the +// function identified by the symbol sym. If sym is not an intrinsic call, returns nil. +func findIntrinsic(sym *types.Sym) intrinsicBuilder { + if sym == nil || sym.Pkg == nil { + return nil + } + pkg := sym.Pkg.Path + if sym.Pkg == ir.Pkgs.Runtime { + pkg = "runtime" + } + if base.Flag.Race && pkg == "sync/atomic" { + // The race detector needs to be able to intercept these calls. + // We can't intrinsify them. + return nil + } + // Skip intrinsifying math functions (which may contain hard-float + // instructions) when soft-float + if Arch.SoftFloat && pkg == "math" { + return nil + } + + fn := sym.Name + if ssa.IntrinsicsDisable { + if pkg == "runtime" && (fn == "getcallerpc" || fn == "getcallersp" || fn == "getclosureptr") { + // These runtime functions don't have definitions, must be intrinsics. + } else { + return nil + } + } + return intrinsics[intrinsicKey{Arch.LinkArch.Arch, pkg, fn}] +} + +func IsIntrinsicCall(n *ir.CallExpr) bool { + if n == nil { + return false + } + name, ok := n.X.(*ir.Name) + if !ok { + return false + } + return findIntrinsic(name.Sym()) != nil +} + +// intrinsicCall converts a call to a recognized intrinsic function into the intrinsic SSA operation. +func (s *state) intrinsicCall(n *ir.CallExpr) *ssa.Value { + v := findIntrinsic(n.X.Sym())(s, n, s.intrinsicArgs(n)) + if ssa.IntrinsicsDebug > 0 { + x := v + if x == nil { + x = s.mem() + } + if x.Op == ssa.OpSelect0 || x.Op == ssa.OpSelect1 { + x = x.Args[0] + } + base.WarnfAt(n.Pos(), "intrinsic substitution for %v with %s", n.X.Sym().Name, x.LongString()) + } + return v +} + +// intrinsicArgs extracts args from n, evaluates them to SSA values, and returns them. +func (s *state) intrinsicArgs(n *ir.CallExpr) []*ssa.Value { + args := make([]*ssa.Value, len(n.Args)) + for i, n := range n.Args { + args[i] = s.expr(n) + } + return args +} + +// openDeferRecord adds code to evaluate and store the function for an open-code defer +// call, and records info about the defer, so we can generate proper code on the +// exit paths. n is the sub-node of the defer node that is the actual function +// call. We will also record funcdata information on where the function is stored +// (as well as the deferBits variable), and this will enable us to run the proper +// defer calls during panics. +func (s *state) openDeferRecord(n *ir.CallExpr) { + if len(n.Args) != 0 || n.Op() != ir.OCALLFUNC || n.X.Type().NumResults() != 0 { + s.Fatalf("defer call with arguments or results: %v", n) + } + + opendefer := &openDeferInfo{ + n: n, + } + fn := n.X + // We must always store the function value in a stack slot for the + // runtime panic code to use. But in the defer exit code, we will + // call the function directly if it is a static function. + closureVal := s.expr(fn) + closure := s.openDeferSave(fn.Type(), closureVal) + opendefer.closureNode = closure.Aux.(*ir.Name) + if !(fn.Op() == ir.ONAME && fn.(*ir.Name).Class == ir.PFUNC) { + opendefer.closure = closure + } + index := len(s.openDefers) + s.openDefers = append(s.openDefers, opendefer) + + // Update deferBits only after evaluation and storage to stack of + // the function is successful. + bitvalue := s.constInt8(types.Types[types.TUINT8], 1<<uint(index)) + newDeferBits := s.newValue2(ssa.OpOr8, types.Types[types.TUINT8], s.variable(deferBitsVar, types.Types[types.TUINT8]), bitvalue) + s.vars[deferBitsVar] = newDeferBits + s.store(types.Types[types.TUINT8], s.deferBitsAddr, newDeferBits) +} + +// openDeferSave generates SSA nodes to store a value (with type t) for an +// open-coded defer at an explicit autotmp location on the stack, so it can be +// reloaded and used for the appropriate call on exit. Type t must be a function type +// (therefore SSAable). val is the value to be stored. The function returns an SSA +// value representing a pointer to the autotmp location. +func (s *state) openDeferSave(t *types.Type, val *ssa.Value) *ssa.Value { + if !TypeOK(t) { + s.Fatalf("openDeferSave of non-SSA-able type %v val=%v", t, val) + } + if !t.HasPointers() { + s.Fatalf("openDeferSave of pointerless type %v val=%v", t, val) + } + pos := val.Pos + temp := typecheck.TempAt(pos.WithNotStmt(), s.curfn, t) + temp.SetOpenDeferSlot(true) + var addrTemp *ssa.Value + // Use OpVarLive to make sure stack slot for the closure is not removed by + // dead-store elimination + if s.curBlock.ID != s.f.Entry.ID { + // Force the tmp storing this defer function to be declared in the entry + // block, so that it will be live for the defer exit code (which will + // actually access it only if the associated defer call has been activated). + if t.HasPointers() { + s.defvars[s.f.Entry.ID][memVar] = s.f.Entry.NewValue1A(src.NoXPos, ssa.OpVarDef, types.TypeMem, temp, s.defvars[s.f.Entry.ID][memVar]) + } + s.defvars[s.f.Entry.ID][memVar] = s.f.Entry.NewValue1A(src.NoXPos, ssa.OpVarLive, types.TypeMem, temp, s.defvars[s.f.Entry.ID][memVar]) + addrTemp = s.f.Entry.NewValue2A(src.NoXPos, ssa.OpLocalAddr, types.NewPtr(temp.Type()), temp, s.sp, s.defvars[s.f.Entry.ID][memVar]) + } else { + // Special case if we're still in the entry block. We can't use + // the above code, since s.defvars[s.f.Entry.ID] isn't defined + // until we end the entry block with s.endBlock(). + if t.HasPointers() { + s.vars[memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, temp, s.mem(), false) + } + s.vars[memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, temp, s.mem(), false) + addrTemp = s.newValue2Apos(ssa.OpLocalAddr, types.NewPtr(temp.Type()), temp, s.sp, s.mem(), false) + } + // Since we may use this temp during exit depending on the + // deferBits, we must define it unconditionally on entry. + // Therefore, we must make sure it is zeroed out in the entry + // block if it contains pointers, else GC may wrongly follow an + // uninitialized pointer value. + temp.SetNeedzero(true) + // We are storing to the stack, hence we can avoid the full checks in + // storeType() (no write barrier) and do a simple store(). + s.store(t, addrTemp, val) + return addrTemp +} + +// openDeferExit generates SSA for processing all the open coded defers at exit. +// The code involves loading deferBits, and checking each of the bits to see if +// the corresponding defer statement was executed. For each bit that is turned +// on, the associated defer call is made. +func (s *state) openDeferExit() { + deferExit := s.f.NewBlock(ssa.BlockPlain) + s.endBlock().AddEdgeTo(deferExit) + s.startBlock(deferExit) + s.lastDeferExit = deferExit + s.lastDeferCount = len(s.openDefers) + zeroval := s.constInt8(types.Types[types.TUINT8], 0) + // Test for and run defers in reverse order + for i := len(s.openDefers) - 1; i >= 0; i-- { + r := s.openDefers[i] + bCond := s.f.NewBlock(ssa.BlockPlain) + bEnd := s.f.NewBlock(ssa.BlockPlain) + + deferBits := s.variable(deferBitsVar, types.Types[types.TUINT8]) + // Generate code to check if the bit associated with the current + // defer is set. + bitval := s.constInt8(types.Types[types.TUINT8], 1<<uint(i)) + andval := s.newValue2(ssa.OpAnd8, types.Types[types.TUINT8], deferBits, bitval) + eqVal := s.newValue2(ssa.OpEq8, types.Types[types.TBOOL], andval, zeroval) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(eqVal) + b.AddEdgeTo(bEnd) + b.AddEdgeTo(bCond) + bCond.AddEdgeTo(bEnd) + s.startBlock(bCond) + + // Clear this bit in deferBits and force store back to stack, so + // we will not try to re-run this defer call if this defer call panics. + nbitval := s.newValue1(ssa.OpCom8, types.Types[types.TUINT8], bitval) + maskedval := s.newValue2(ssa.OpAnd8, types.Types[types.TUINT8], deferBits, nbitval) + s.store(types.Types[types.TUINT8], s.deferBitsAddr, maskedval) + // Use this value for following tests, so we keep previous + // bits cleared. + s.vars[deferBitsVar] = maskedval + + // Generate code to call the function call of the defer, using the + // closure that were stored in argtmps at the point of the defer + // statement. + fn := r.n.X + stksize := fn.Type().ArgWidth() + var callArgs []*ssa.Value + var call *ssa.Value + if r.closure != nil { + v := s.load(r.closure.Type.Elem(), r.closure) + s.maybeNilCheckClosure(v, callDefer) + codeptr := s.rawLoad(types.Types[types.TUINTPTR], v) + aux := ssa.ClosureAuxCall(s.f.ABIDefault.ABIAnalyzeTypes(nil, nil, nil)) + call = s.newValue2A(ssa.OpClosureLECall, aux.LateExpansionResultType(), aux, codeptr, v) + } else { + aux := ssa.StaticAuxCall(fn.(*ir.Name).Linksym(), s.f.ABIDefault.ABIAnalyzeTypes(nil, nil, nil)) + call = s.newValue0A(ssa.OpStaticLECall, aux.LateExpansionResultType(), aux) + } + callArgs = append(callArgs, s.mem()) + call.AddArgs(callArgs...) + call.AuxInt = stksize + s.vars[memVar] = s.newValue1I(ssa.OpSelectN, types.TypeMem, 0, call) + // Make sure that the stack slots with pointers are kept live + // through the call (which is a pre-emption point). Also, we will + // use the first call of the last defer exit to compute liveness + // for the deferreturn, so we want all stack slots to be live. + if r.closureNode != nil { + s.vars[memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, r.closureNode, s.mem(), false) + } + + s.endBlock() + s.startBlock(bEnd) + } +} + +func (s *state) callResult(n *ir.CallExpr, k callKind) *ssa.Value { + return s.call(n, k, false) +} + +func (s *state) callAddr(n *ir.CallExpr, k callKind) *ssa.Value { + return s.call(n, k, true) +} + +// Calls the function n using the specified call type. +// Returns the address of the return value (or nil if none). +func (s *state) call(n *ir.CallExpr, k callKind, returnResultAddr bool) *ssa.Value { + s.prevCall = nil + var callee *ir.Name // target function (if static) + var closure *ssa.Value // ptr to closure to run (if dynamic) + var codeptr *ssa.Value // ptr to target code (if dynamic) + var rcvr *ssa.Value // receiver to set + fn := n.X + var ACArgs []*types.Type // AuxCall args + var ACResults []*types.Type // AuxCall results + var callArgs []*ssa.Value // For late-expansion, the args themselves (not stored, args to the call instead). + + callABI := s.f.ABIDefault + + if k != callNormal && k != callTail && (len(n.Args) != 0 || n.Op() == ir.OCALLINTER || n.X.Type().NumResults() != 0) { + s.Fatalf("go/defer call with arguments: %v", n) + } + + switch n.Op() { + case ir.OCALLFUNC: + if (k == callNormal || k == callTail) && fn.Op() == ir.ONAME && fn.(*ir.Name).Class == ir.PFUNC { + fn := fn.(*ir.Name) + callee = fn + if buildcfg.Experiment.RegabiArgs { + // This is a static call, so it may be + // a direct call to a non-ABIInternal + // function. fn.Func may be nil for + // some compiler-generated functions, + // but those are all ABIInternal. + if fn.Func != nil { + callABI = abiForFunc(fn.Func, s.f.ABI0, s.f.ABI1) + } + } else { + // TODO(register args) remove after register abi is working + inRegistersImported := fn.Pragma()&ir.RegisterParams != 0 + inRegistersSamePackage := fn.Func != nil && fn.Func.Pragma&ir.RegisterParams != 0 + if inRegistersImported || inRegistersSamePackage { + callABI = s.f.ABI1 + } + } + break + } + closure = s.expr(fn) + if k != callDefer && k != callDeferStack { + // Deferred nil function needs to panic when the function is invoked, + // not the point of defer statement. + s.maybeNilCheckClosure(closure, k) + } + case ir.OCALLINTER: + if fn.Op() != ir.ODOTINTER { + s.Fatalf("OCALLINTER: n.Left not an ODOTINTER: %v", fn.Op()) + } + fn := fn.(*ir.SelectorExpr) + var iclosure *ssa.Value + iclosure, rcvr = s.getClosureAndRcvr(fn) + if k == callNormal { + codeptr = s.load(types.Types[types.TUINTPTR], iclosure) + } else { + closure = iclosure + } + } + + params := callABI.ABIAnalyze(n.X.Type(), false /* Do not set (register) nNames from caller side -- can cause races. */) + types.CalcSize(fn.Type()) + stksize := params.ArgWidth() // includes receiver, args, and results + + res := n.X.Type().Results() + if k == callNormal || k == callTail { + for _, p := range params.OutParams() { + ACResults = append(ACResults, p.Type) + } + } + + var call *ssa.Value + if k == callDeferStack { + // Make a defer struct d on the stack. + if stksize != 0 { + s.Fatalf("deferprocStack with non-zero stack size %d: %v", stksize, n) + } + + t := deferstruct() + d := typecheck.TempAt(n.Pos(), s.curfn, t) + + if t.HasPointers() { + s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, d, s.mem()) + } + addr := s.addr(d) + + // Must match deferstruct() below and src/runtime/runtime2.go:_defer. + // 0: started, set in deferprocStack + // 1: heap, set in deferprocStack + // 2: openDefer + // 3: sp, set in deferprocStack + // 4: pc, set in deferprocStack + // 5: fn + s.store(closure.Type, + s.newValue1I(ssa.OpOffPtr, closure.Type.PtrTo(), t.FieldOff(5), addr), + closure) + // 6: panic, set in deferprocStack + // 7: link, set in deferprocStack + // 8: fd + // 9: varp + // 10: framepc + + // Call runtime.deferprocStack with pointer to _defer record. + ACArgs = append(ACArgs, types.Types[types.TUINTPTR]) + aux := ssa.StaticAuxCall(ir.Syms.DeferprocStack, s.f.ABIDefault.ABIAnalyzeTypes(nil, ACArgs, ACResults)) + callArgs = append(callArgs, addr, s.mem()) + call = s.newValue0A(ssa.OpStaticLECall, aux.LateExpansionResultType(), aux) + call.AddArgs(callArgs...) + call.AuxInt = int64(types.PtrSize) // deferprocStack takes a *_defer arg + } else { + // Store arguments to stack, including defer/go arguments and receiver for method calls. + // These are written in SP-offset order. + argStart := base.Ctxt.Arch.FixedFrameSize + // Defer/go args. + if k != callNormal && k != callTail { + // Write closure (arg to newproc/deferproc). + ACArgs = append(ACArgs, types.Types[types.TUINTPTR]) // not argExtra + callArgs = append(callArgs, closure) + stksize += int64(types.PtrSize) + argStart += int64(types.PtrSize) + } + + // Set receiver (for interface calls). + if rcvr != nil { + callArgs = append(callArgs, rcvr) + } + + // Write args. + t := n.X.Type() + args := n.Args + + for _, p := range params.InParams() { // includes receiver for interface calls + ACArgs = append(ACArgs, p.Type) + } + + // Split the entry block if there are open defers, because later calls to + // openDeferSave may cause a mismatch between the mem for an OpDereference + // and the call site which uses it. See #49282. + if s.curBlock.ID == s.f.Entry.ID && s.hasOpenDefers { + b := s.endBlock() + b.Kind = ssa.BlockPlain + curb := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(curb) + s.startBlock(curb) + } + + for i, n := range args { + callArgs = append(callArgs, s.putArg(n, t.Params().Field(i).Type)) + } + + callArgs = append(callArgs, s.mem()) + + // call target + switch { + case k == callDefer: + aux := ssa.StaticAuxCall(ir.Syms.Deferproc, s.f.ABIDefault.ABIAnalyzeTypes(nil, ACArgs, ACResults)) // TODO paramResultInfo for DeferProc + call = s.newValue0A(ssa.OpStaticLECall, aux.LateExpansionResultType(), aux) + case k == callGo: + aux := ssa.StaticAuxCall(ir.Syms.Newproc, s.f.ABIDefault.ABIAnalyzeTypes(nil, ACArgs, ACResults)) + call = s.newValue0A(ssa.OpStaticLECall, aux.LateExpansionResultType(), aux) // TODO paramResultInfo for NewProc + case closure != nil: + // rawLoad because loading the code pointer from a + // closure is always safe, but IsSanitizerSafeAddr + // can't always figure that out currently, and it's + // critical that we not clobber any arguments already + // stored onto the stack. + codeptr = s.rawLoad(types.Types[types.TUINTPTR], closure) + aux := ssa.ClosureAuxCall(callABI.ABIAnalyzeTypes(nil, ACArgs, ACResults)) + call = s.newValue2A(ssa.OpClosureLECall, aux.LateExpansionResultType(), aux, codeptr, closure) + case codeptr != nil: + // Note that the "receiver" parameter is nil because the actual receiver is the first input parameter. + aux := ssa.InterfaceAuxCall(params) + call = s.newValue1A(ssa.OpInterLECall, aux.LateExpansionResultType(), aux, codeptr) + case callee != nil: + aux := ssa.StaticAuxCall(callTargetLSym(callee), params) + call = s.newValue0A(ssa.OpStaticLECall, aux.LateExpansionResultType(), aux) + if k == callTail { + call.Op = ssa.OpTailLECall + stksize = 0 // Tail call does not use stack. We reuse caller's frame. + } + default: + s.Fatalf("bad call type %v %v", n.Op(), n) + } + call.AddArgs(callArgs...) + call.AuxInt = stksize // Call operations carry the argsize of the callee along with them + } + s.prevCall = call + s.vars[memVar] = s.newValue1I(ssa.OpSelectN, types.TypeMem, int64(len(ACResults)), call) + // Insert VarLive opcodes. + for _, v := range n.KeepAlive { + if !v.Addrtaken() { + s.Fatalf("KeepAlive variable %v must have Addrtaken set", v) + } + switch v.Class { + case ir.PAUTO, ir.PPARAM, ir.PPARAMOUT: + default: + s.Fatalf("KeepAlive variable %v must be Auto or Arg", v) + } + s.vars[memVar] = s.newValue1A(ssa.OpVarLive, types.TypeMem, v, s.mem()) + } + + // Finish block for defers + if k == callDefer || k == callDeferStack { + b := s.endBlock() + b.Kind = ssa.BlockDefer + b.SetControl(call) + bNext := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bNext) + // Add recover edge to exit code. + r := s.f.NewBlock(ssa.BlockPlain) + s.startBlock(r) + s.exit() + b.AddEdgeTo(r) + b.Likely = ssa.BranchLikely + s.startBlock(bNext) + } + + if res.NumFields() == 0 || k != callNormal { + // call has no return value. Continue with the next statement. + return nil + } + fp := res.Field(0) + if returnResultAddr { + return s.resultAddrOfCall(call, 0, fp.Type) + } + return s.newValue1I(ssa.OpSelectN, fp.Type, 0, call) +} + +// maybeNilCheckClosure checks if a nil check of a closure is needed in some +// architecture-dependent situations and, if so, emits the nil check. +func (s *state) maybeNilCheckClosure(closure *ssa.Value, k callKind) { + if Arch.LinkArch.Family == sys.Wasm || buildcfg.GOOS == "aix" && k != callGo { + // On AIX, the closure needs to be verified as fn can be nil, except if it's a call go. This needs to be handled by the runtime to have the "go of nil func value" error. + // TODO(neelance): On other architectures this should be eliminated by the optimization steps + s.nilCheck(closure) + } +} + +// getClosureAndRcvr returns values for the appropriate closure and receiver of an +// interface call +func (s *state) getClosureAndRcvr(fn *ir.SelectorExpr) (*ssa.Value, *ssa.Value) { + i := s.expr(fn.X) + itab := s.newValue1(ssa.OpITab, types.Types[types.TUINTPTR], i) + s.nilCheck(itab) + itabidx := fn.Offset() + 2*int64(types.PtrSize) + 8 // offset of fun field in runtime.itab + closure := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.UintptrPtr, itabidx, itab) + rcvr := s.newValue1(ssa.OpIData, s.f.Config.Types.BytePtr, i) + return closure, rcvr +} + +// etypesign returns the signed-ness of e, for integer/pointer etypes. +// -1 means signed, +1 means unsigned, 0 means non-integer/non-pointer. +func etypesign(e types.Kind) int8 { + switch e { + case types.TINT8, types.TINT16, types.TINT32, types.TINT64, types.TINT: + return -1 + case types.TUINT8, types.TUINT16, types.TUINT32, types.TUINT64, types.TUINT, types.TUINTPTR, types.TUNSAFEPTR: + return +1 + } + return 0 +} + +// addr converts the address of the expression n to SSA, adds it to s and returns the SSA result. +// The value that the returned Value represents is guaranteed to be non-nil. +func (s *state) addr(n ir.Node) *ssa.Value { + if n.Op() != ir.ONAME { + s.pushLine(n.Pos()) + defer s.popLine() + } + + if s.canSSA(n) { + s.Fatalf("addr of canSSA expression: %+v", n) + } + + t := types.NewPtr(n.Type()) + linksymOffset := func(lsym *obj.LSym, offset int64) *ssa.Value { + v := s.entryNewValue1A(ssa.OpAddr, t, lsym, s.sb) + // TODO: Make OpAddr use AuxInt as well as Aux. + if offset != 0 { + v = s.entryNewValue1I(ssa.OpOffPtr, v.Type, offset, v) + } + return v + } + switch n.Op() { + case ir.OLINKSYMOFFSET: + no := n.(*ir.LinksymOffsetExpr) + return linksymOffset(no.Linksym, no.Offset_) + case ir.ONAME: + n := n.(*ir.Name) + if n.Heapaddr != nil { + return s.expr(n.Heapaddr) + } + switch n.Class { + case ir.PEXTERN: + // global variable + return linksymOffset(n.Linksym(), 0) + case ir.PPARAM: + // parameter slot + v := s.decladdrs[n] + if v != nil { + return v + } + s.Fatalf("addr of undeclared ONAME %v. declared: %v", n, s.decladdrs) + return nil + case ir.PAUTO: + return s.newValue2Apos(ssa.OpLocalAddr, t, n, s.sp, s.mem(), !ir.IsAutoTmp(n)) + + case ir.PPARAMOUT: // Same as PAUTO -- cannot generate LEA early. + // ensure that we reuse symbols for out parameters so + // that cse works on their addresses + return s.newValue2Apos(ssa.OpLocalAddr, t, n, s.sp, s.mem(), true) + default: + s.Fatalf("variable address class %v not implemented", n.Class) + return nil + } + case ir.ORESULT: + // load return from callee + n := n.(*ir.ResultExpr) + return s.resultAddrOfCall(s.prevCall, n.Index, n.Type()) + case ir.OINDEX: + n := n.(*ir.IndexExpr) + if n.X.Type().IsSlice() { + a := s.expr(n.X) + i := s.expr(n.Index) + len := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], a) + i = s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded()) + p := s.newValue1(ssa.OpSlicePtr, t, a) + return s.newValue2(ssa.OpPtrIndex, t, p, i) + } else { // array + a := s.addr(n.X) + i := s.expr(n.Index) + len := s.constInt(types.Types[types.TINT], n.X.Type().NumElem()) + i = s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded()) + return s.newValue2(ssa.OpPtrIndex, types.NewPtr(n.X.Type().Elem()), a, i) + } + case ir.ODEREF: + n := n.(*ir.StarExpr) + return s.exprPtr(n.X, n.Bounded(), n.Pos()) + case ir.ODOT: + n := n.(*ir.SelectorExpr) + p := s.addr(n.X) + return s.newValue1I(ssa.OpOffPtr, t, n.Offset(), p) + case ir.ODOTPTR: + n := n.(*ir.SelectorExpr) + p := s.exprPtr(n.X, n.Bounded(), n.Pos()) + return s.newValue1I(ssa.OpOffPtr, t, n.Offset(), p) + case ir.OCONVNOP: + n := n.(*ir.ConvExpr) + if n.Type() == n.X.Type() { + return s.addr(n.X) + } + addr := s.addr(n.X) + return s.newValue1(ssa.OpCopy, t, addr) // ensure that addr has the right type + case ir.OCALLFUNC, ir.OCALLINTER: + n := n.(*ir.CallExpr) + return s.callAddr(n, callNormal) + case ir.ODOTTYPE, ir.ODYNAMICDOTTYPE: + var v *ssa.Value + if n.Op() == ir.ODOTTYPE { + v, _ = s.dottype(n.(*ir.TypeAssertExpr), false) + } else { + v, _ = s.dynamicDottype(n.(*ir.DynamicTypeAssertExpr), false) + } + if v.Op != ssa.OpLoad { + s.Fatalf("dottype of non-load") + } + if v.Args[1] != s.mem() { + s.Fatalf("memory no longer live from dottype load") + } + return v.Args[0] + default: + s.Fatalf("unhandled addr %v", n.Op()) + return nil + } +} + +// canSSA reports whether n is SSA-able. +// n must be an ONAME (or an ODOT sequence with an ONAME base). +func (s *state) canSSA(n ir.Node) bool { + if base.Flag.N != 0 { + return false + } + for { + nn := n + if nn.Op() == ir.ODOT { + nn := nn.(*ir.SelectorExpr) + n = nn.X + continue + } + if nn.Op() == ir.OINDEX { + nn := nn.(*ir.IndexExpr) + if nn.X.Type().IsArray() { + n = nn.X + continue + } + } + break + } + if n.Op() != ir.ONAME { + return false + } + return s.canSSAName(n.(*ir.Name)) && TypeOK(n.Type()) +} + +func (s *state) canSSAName(name *ir.Name) bool { + if name.Addrtaken() || !name.OnStack() { + return false + } + switch name.Class { + case ir.PPARAMOUT: + if s.hasdefer { + // TODO: handle this case? Named return values must be + // in memory so that the deferred function can see them. + // Maybe do: if !strings.HasPrefix(n.String(), "~") { return false } + // Or maybe not, see issue 18860. Even unnamed return values + // must be written back so if a defer recovers, the caller can see them. + return false + } + if s.cgoUnsafeArgs { + // Cgo effectively takes the address of all result args, + // but the compiler can't see that. + return false + } + } + return true + // TODO: try to make more variables SSAable? +} + +// TypeOK reports whether variables of type t are SSA-able. +func TypeOK(t *types.Type) bool { + types.CalcSize(t) + if t.Size() > int64(4*types.PtrSize) { + // 4*Widthptr is an arbitrary constant. We want it + // to be at least 3*Widthptr so slices can be registerized. + // Too big and we'll introduce too much register pressure. + return false + } + switch t.Kind() { + case types.TARRAY: + // We can't do larger arrays because dynamic indexing is + // not supported on SSA variables. + // TODO: allow if all indexes are constant. + if t.NumElem() <= 1 { + return TypeOK(t.Elem()) + } + return false + case types.TSTRUCT: + if t.NumFields() > ssa.MaxStruct { + return false + } + for _, t1 := range t.Fields().Slice() { + if !TypeOK(t1.Type) { + return false + } + } + return true + default: + return true + } +} + +// exprPtr evaluates n to a pointer and nil-checks it. +func (s *state) exprPtr(n ir.Node, bounded bool, lineno src.XPos) *ssa.Value { + p := s.expr(n) + if bounded || n.NonNil() { + if s.f.Frontend().Debug_checknil() && lineno.Line() > 1 { + s.f.Warnl(lineno, "removed nil check") + } + return p + } + p = s.nilCheck(p) + return p +} + +// nilCheck generates nil pointer checking code. +// Used only for automatically inserted nil checks, +// not for user code like 'x != nil'. +// Returns a "definitely not nil" copy of x to ensure proper ordering +// of the uses of the post-nilcheck pointer. +func (s *state) nilCheck(ptr *ssa.Value) *ssa.Value { + if base.Debug.DisableNil != 0 || s.curfn.NilCheckDisabled() { + return ptr + } + return s.newValue2(ssa.OpNilCheck, ptr.Type, ptr, s.mem()) +} + +// boundsCheck generates bounds checking code. Checks if 0 <= idx <[=] len, branches to exit if not. +// Starts a new block on return. +// On input, len must be converted to full int width and be nonnegative. +// Returns idx converted to full int width. +// If bounded is true then caller guarantees the index is not out of bounds +// (but boundsCheck will still extend the index to full int width). +func (s *state) boundsCheck(idx, len *ssa.Value, kind ssa.BoundsKind, bounded bool) *ssa.Value { + idx = s.extendIndex(idx, len, kind, bounded) + + if bounded || base.Flag.B != 0 { + // If bounded or bounds checking is flag-disabled, then no check necessary, + // just return the extended index. + // + // Here, bounded == true if the compiler generated the index itself, + // such as in the expansion of a slice initializer. These indexes are + // compiler-generated, not Go program variables, so they cannot be + // attacker-controlled, so we can omit Spectre masking as well. + // + // Note that we do not want to omit Spectre masking in code like: + // + // if 0 <= i && i < len(x) { + // use(x[i]) + // } + // + // Lucky for us, bounded==false for that code. + // In that case (handled below), we emit a bound check (and Spectre mask) + // and then the prove pass will remove the bounds check. + // In theory the prove pass could potentially remove certain + // Spectre masks, but it's very delicate and probably better + // to be conservative and leave them all in. + return idx + } + + bNext := s.f.NewBlock(ssa.BlockPlain) + bPanic := s.f.NewBlock(ssa.BlockExit) + + if !idx.Type.IsSigned() { + switch kind { + case ssa.BoundsIndex: + kind = ssa.BoundsIndexU + case ssa.BoundsSliceAlen: + kind = ssa.BoundsSliceAlenU + case ssa.BoundsSliceAcap: + kind = ssa.BoundsSliceAcapU + case ssa.BoundsSliceB: + kind = ssa.BoundsSliceBU + case ssa.BoundsSlice3Alen: + kind = ssa.BoundsSlice3AlenU + case ssa.BoundsSlice3Acap: + kind = ssa.BoundsSlice3AcapU + case ssa.BoundsSlice3B: + kind = ssa.BoundsSlice3BU + case ssa.BoundsSlice3C: + kind = ssa.BoundsSlice3CU + } + } + + var cmp *ssa.Value + if kind == ssa.BoundsIndex || kind == ssa.BoundsIndexU { + cmp = s.newValue2(ssa.OpIsInBounds, types.Types[types.TBOOL], idx, len) + } else { + cmp = s.newValue2(ssa.OpIsSliceInBounds, types.Types[types.TBOOL], idx, len) + } + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.Likely = ssa.BranchLikely + b.AddEdgeTo(bNext) + b.AddEdgeTo(bPanic) + + s.startBlock(bPanic) + if Arch.LinkArch.Family == sys.Wasm { + // TODO(khr): figure out how to do "register" based calling convention for bounds checks. + // Should be similar to gcWriteBarrier, but I can't make it work. + s.rtcall(BoundsCheckFunc[kind], false, nil, idx, len) + } else { + mem := s.newValue3I(ssa.OpPanicBounds, types.TypeMem, int64(kind), idx, len, s.mem()) + s.endBlock().SetControl(mem) + } + s.startBlock(bNext) + + // In Spectre index mode, apply an appropriate mask to avoid speculative out-of-bounds accesses. + if base.Flag.Cfg.SpectreIndex { + op := ssa.OpSpectreIndex + if kind != ssa.BoundsIndex && kind != ssa.BoundsIndexU { + op = ssa.OpSpectreSliceIndex + } + idx = s.newValue2(op, types.Types[types.TINT], idx, len) + } + + return idx +} + +// If cmp (a bool) is false, panic using the given function. +func (s *state) check(cmp *ssa.Value, fn *obj.LSym) { + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.Likely = ssa.BranchLikely + bNext := s.f.NewBlock(ssa.BlockPlain) + line := s.peekPos() + pos := base.Ctxt.PosTable.Pos(line) + fl := funcLine{f: fn, base: pos.Base(), line: pos.Line()} + bPanic := s.panics[fl] + if bPanic == nil { + bPanic = s.f.NewBlock(ssa.BlockPlain) + s.panics[fl] = bPanic + s.startBlock(bPanic) + // The panic call takes/returns memory to ensure that the right + // memory state is observed if the panic happens. + s.rtcall(fn, false, nil) + } + b.AddEdgeTo(bNext) + b.AddEdgeTo(bPanic) + s.startBlock(bNext) +} + +func (s *state) intDivide(n ir.Node, a, b *ssa.Value) *ssa.Value { + needcheck := true + switch b.Op { + case ssa.OpConst8, ssa.OpConst16, ssa.OpConst32, ssa.OpConst64: + if b.AuxInt != 0 { + needcheck = false + } + } + if needcheck { + // do a size-appropriate check for zero + cmp := s.newValue2(s.ssaOp(ir.ONE, n.Type()), types.Types[types.TBOOL], b, s.zeroVal(n.Type())) + s.check(cmp, ir.Syms.Panicdivide) + } + return s.newValue2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b) +} + +// rtcall issues a call to the given runtime function fn with the listed args. +// Returns a slice of results of the given result types. +// The call is added to the end of the current block. +// If returns is false, the block is marked as an exit block. +func (s *state) rtcall(fn *obj.LSym, returns bool, results []*types.Type, args ...*ssa.Value) []*ssa.Value { + s.prevCall = nil + // Write args to the stack + off := base.Ctxt.Arch.FixedFrameSize + var callArgs []*ssa.Value + var callArgTypes []*types.Type + + for _, arg := range args { + t := arg.Type + off = types.RoundUp(off, t.Alignment()) + size := t.Size() + callArgs = append(callArgs, arg) + callArgTypes = append(callArgTypes, t) + off += size + } + off = types.RoundUp(off, int64(types.RegSize)) + + // Issue call + var call *ssa.Value + aux := ssa.StaticAuxCall(fn, s.f.ABIDefault.ABIAnalyzeTypes(nil, callArgTypes, results)) + callArgs = append(callArgs, s.mem()) + call = s.newValue0A(ssa.OpStaticLECall, aux.LateExpansionResultType(), aux) + call.AddArgs(callArgs...) + s.vars[memVar] = s.newValue1I(ssa.OpSelectN, types.TypeMem, int64(len(results)), call) + + if !returns { + // Finish block + b := s.endBlock() + b.Kind = ssa.BlockExit + b.SetControl(call) + call.AuxInt = off - base.Ctxt.Arch.FixedFrameSize + if len(results) > 0 { + s.Fatalf("panic call can't have results") + } + return nil + } + + // Load results + res := make([]*ssa.Value, len(results)) + for i, t := range results { + off = types.RoundUp(off, t.Alignment()) + res[i] = s.resultOfCall(call, int64(i), t) + off += t.Size() + } + off = types.RoundUp(off, int64(types.PtrSize)) + + // Remember how much callee stack space we needed. + call.AuxInt = off + + return res +} + +// do *left = right for type t. +func (s *state) storeType(t *types.Type, left, right *ssa.Value, skip skipMask, leftIsStmt bool) { + s.instrument(t, left, instrumentWrite) + + if skip == 0 && (!t.HasPointers() || ssa.IsStackAddr(left)) { + // Known to not have write barrier. Store the whole type. + s.vars[memVar] = s.newValue3Apos(ssa.OpStore, types.TypeMem, t, left, right, s.mem(), leftIsStmt) + return + } + + // store scalar fields first, so write barrier stores for + // pointer fields can be grouped together, and scalar values + // don't need to be live across the write barrier call. + // TODO: if the writebarrier pass knows how to reorder stores, + // we can do a single store here as long as skip==0. + s.storeTypeScalars(t, left, right, skip) + if skip&skipPtr == 0 && t.HasPointers() { + s.storeTypePtrs(t, left, right) + } +} + +// do *left = right for all scalar (non-pointer) parts of t. +func (s *state) storeTypeScalars(t *types.Type, left, right *ssa.Value, skip skipMask) { + switch { + case t.IsBoolean() || t.IsInteger() || t.IsFloat() || t.IsComplex(): + s.store(t, left, right) + case t.IsPtrShaped(): + if t.IsPtr() && t.Elem().NotInHeap() { + s.store(t, left, right) // see issue 42032 + } + // otherwise, no scalar fields. + case t.IsString(): + if skip&skipLen != 0 { + return + } + len := s.newValue1(ssa.OpStringLen, types.Types[types.TINT], right) + lenAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, s.config.PtrSize, left) + s.store(types.Types[types.TINT], lenAddr, len) + case t.IsSlice(): + if skip&skipLen == 0 { + len := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], right) + lenAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, s.config.PtrSize, left) + s.store(types.Types[types.TINT], lenAddr, len) + } + if skip&skipCap == 0 { + cap := s.newValue1(ssa.OpSliceCap, types.Types[types.TINT], right) + capAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, 2*s.config.PtrSize, left) + s.store(types.Types[types.TINT], capAddr, cap) + } + case t.IsInterface(): + // itab field doesn't need a write barrier (even though it is a pointer). + itab := s.newValue1(ssa.OpITab, s.f.Config.Types.BytePtr, right) + s.store(types.Types[types.TUINTPTR], left, itab) + case t.IsStruct(): + n := t.NumFields() + for i := 0; i < n; i++ { + ft := t.FieldType(i) + addr := s.newValue1I(ssa.OpOffPtr, ft.PtrTo(), t.FieldOff(i), left) + val := s.newValue1I(ssa.OpStructSelect, ft, int64(i), right) + s.storeTypeScalars(ft, addr, val, 0) + } + case t.IsArray() && t.NumElem() == 0: + // nothing + case t.IsArray() && t.NumElem() == 1: + s.storeTypeScalars(t.Elem(), left, s.newValue1I(ssa.OpArraySelect, t.Elem(), 0, right), 0) + default: + s.Fatalf("bad write barrier type %v", t) + } +} + +// do *left = right for all pointer parts of t. +func (s *state) storeTypePtrs(t *types.Type, left, right *ssa.Value) { + switch { + case t.IsPtrShaped(): + if t.IsPtr() && t.Elem().NotInHeap() { + break // see issue 42032 + } + s.store(t, left, right) + case t.IsString(): + ptr := s.newValue1(ssa.OpStringPtr, s.f.Config.Types.BytePtr, right) + s.store(s.f.Config.Types.BytePtr, left, ptr) + case t.IsSlice(): + elType := types.NewPtr(t.Elem()) + ptr := s.newValue1(ssa.OpSlicePtr, elType, right) + s.store(elType, left, ptr) + case t.IsInterface(): + // itab field is treated as a scalar. + idata := s.newValue1(ssa.OpIData, s.f.Config.Types.BytePtr, right) + idataAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.BytePtrPtr, s.config.PtrSize, left) + s.store(s.f.Config.Types.BytePtr, idataAddr, idata) + case t.IsStruct(): + n := t.NumFields() + for i := 0; i < n; i++ { + ft := t.FieldType(i) + if !ft.HasPointers() { + continue + } + addr := s.newValue1I(ssa.OpOffPtr, ft.PtrTo(), t.FieldOff(i), left) + val := s.newValue1I(ssa.OpStructSelect, ft, int64(i), right) + s.storeTypePtrs(ft, addr, val) + } + case t.IsArray() && t.NumElem() == 0: + // nothing + case t.IsArray() && t.NumElem() == 1: + s.storeTypePtrs(t.Elem(), left, s.newValue1I(ssa.OpArraySelect, t.Elem(), 0, right)) + default: + s.Fatalf("bad write barrier type %v", t) + } +} + +// putArg evaluates n for the purpose of passing it as an argument to a function and returns the value for the call. +func (s *state) putArg(n ir.Node, t *types.Type) *ssa.Value { + var a *ssa.Value + if !TypeOK(t) { + a = s.newValue2(ssa.OpDereference, t, s.addr(n), s.mem()) + } else { + a = s.expr(n) + } + return a +} + +func (s *state) storeArgWithBase(n ir.Node, t *types.Type, base *ssa.Value, off int64) { + pt := types.NewPtr(t) + var addr *ssa.Value + if base == s.sp { + // Use special routine that avoids allocation on duplicate offsets. + addr = s.constOffPtrSP(pt, off) + } else { + addr = s.newValue1I(ssa.OpOffPtr, pt, off, base) + } + + if !TypeOK(t) { + a := s.addr(n) + s.move(t, addr, a) + return + } + + a := s.expr(n) + s.storeType(t, addr, a, 0, false) +} + +// slice computes the slice v[i:j:k] and returns ptr, len, and cap of result. +// i,j,k may be nil, in which case they are set to their default value. +// v may be a slice, string or pointer to an array. +func (s *state) slice(v, i, j, k *ssa.Value, bounded bool) (p, l, c *ssa.Value) { + t := v.Type + var ptr, len, cap *ssa.Value + switch { + case t.IsSlice(): + ptr = s.newValue1(ssa.OpSlicePtr, types.NewPtr(t.Elem()), v) + len = s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], v) + cap = s.newValue1(ssa.OpSliceCap, types.Types[types.TINT], v) + case t.IsString(): + ptr = s.newValue1(ssa.OpStringPtr, types.NewPtr(types.Types[types.TUINT8]), v) + len = s.newValue1(ssa.OpStringLen, types.Types[types.TINT], v) + cap = len + case t.IsPtr(): + if !t.Elem().IsArray() { + s.Fatalf("bad ptr to array in slice %v\n", t) + } + nv := s.nilCheck(v) + ptr = s.newValue1(ssa.OpCopy, types.NewPtr(t.Elem().Elem()), nv) + len = s.constInt(types.Types[types.TINT], t.Elem().NumElem()) + cap = len + default: + s.Fatalf("bad type in slice %v\n", t) + } + + // Set default values + if i == nil { + i = s.constInt(types.Types[types.TINT], 0) + } + if j == nil { + j = len + } + three := true + if k == nil { + three = false + k = cap + } + + // Panic if slice indices are not in bounds. + // Make sure we check these in reverse order so that we're always + // comparing against a value known to be nonnegative. See issue 28797. + if three { + if k != cap { + kind := ssa.BoundsSlice3Alen + if t.IsSlice() { + kind = ssa.BoundsSlice3Acap + } + k = s.boundsCheck(k, cap, kind, bounded) + } + if j != k { + j = s.boundsCheck(j, k, ssa.BoundsSlice3B, bounded) + } + i = s.boundsCheck(i, j, ssa.BoundsSlice3C, bounded) + } else { + if j != k { + kind := ssa.BoundsSliceAlen + if t.IsSlice() { + kind = ssa.BoundsSliceAcap + } + j = s.boundsCheck(j, k, kind, bounded) + } + i = s.boundsCheck(i, j, ssa.BoundsSliceB, bounded) + } + + // Word-sized integer operations. + subOp := s.ssaOp(ir.OSUB, types.Types[types.TINT]) + mulOp := s.ssaOp(ir.OMUL, types.Types[types.TINT]) + andOp := s.ssaOp(ir.OAND, types.Types[types.TINT]) + + // Calculate the length (rlen) and capacity (rcap) of the new slice. + // For strings the capacity of the result is unimportant. However, + // we use rcap to test if we've generated a zero-length slice. + // Use length of strings for that. + rlen := s.newValue2(subOp, types.Types[types.TINT], j, i) + rcap := rlen + if j != k && !t.IsString() { + rcap = s.newValue2(subOp, types.Types[types.TINT], k, i) + } + + if (i.Op == ssa.OpConst64 || i.Op == ssa.OpConst32) && i.AuxInt == 0 { + // No pointer arithmetic necessary. + return ptr, rlen, rcap + } + + // Calculate the base pointer (rptr) for the new slice. + // + // Generate the following code assuming that indexes are in bounds. + // The masking is to make sure that we don't generate a slice + // that points to the next object in memory. We cannot just set + // the pointer to nil because then we would create a nil slice or + // string. + // + // rcap = k - i + // rlen = j - i + // rptr = ptr + (mask(rcap) & (i * stride)) + // + // Where mask(x) is 0 if x==0 and -1 if x>0 and stride is the width + // of the element type. + stride := s.constInt(types.Types[types.TINT], ptr.Type.Elem().Size()) + + // The delta is the number of bytes to offset ptr by. + delta := s.newValue2(mulOp, types.Types[types.TINT], i, stride) + + // If we're slicing to the point where the capacity is zero, + // zero out the delta. + mask := s.newValue1(ssa.OpSlicemask, types.Types[types.TINT], rcap) + delta = s.newValue2(andOp, types.Types[types.TINT], delta, mask) + + // Compute rptr = ptr + delta. + rptr := s.newValue2(ssa.OpAddPtr, ptr.Type, ptr, delta) + + return rptr, rlen, rcap +} + +type u642fcvtTab struct { + leq, cvt2F, and, rsh, or, add ssa.Op + one func(*state, *types.Type, int64) *ssa.Value +} + +var u64_f64 = u642fcvtTab{ + leq: ssa.OpLeq64, + cvt2F: ssa.OpCvt64to64F, + and: ssa.OpAnd64, + rsh: ssa.OpRsh64Ux64, + or: ssa.OpOr64, + add: ssa.OpAdd64F, + one: (*state).constInt64, +} + +var u64_f32 = u642fcvtTab{ + leq: ssa.OpLeq64, + cvt2F: ssa.OpCvt64to32F, + and: ssa.OpAnd64, + rsh: ssa.OpRsh64Ux64, + or: ssa.OpOr64, + add: ssa.OpAdd32F, + one: (*state).constInt64, +} + +func (s *state) uint64Tofloat64(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.uint64Tofloat(&u64_f64, n, x, ft, tt) +} + +func (s *state) uint64Tofloat32(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.uint64Tofloat(&u64_f32, n, x, ft, tt) +} + +func (s *state) uint64Tofloat(cvttab *u642fcvtTab, n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + // if x >= 0 { + // result = (floatY) x + // } else { + // y = uintX(x) ; y = x & 1 + // z = uintX(x) ; z = z >> 1 + // z = z | y + // result = floatY(z) + // result = result + result + // } + // + // Code borrowed from old code generator. + // What's going on: large 64-bit "unsigned" looks like + // negative number to hardware's integer-to-float + // conversion. However, because the mantissa is only + // 63 bits, we don't need the LSB, so instead we do an + // unsigned right shift (divide by two), convert, and + // double. However, before we do that, we need to be + // sure that we do not lose a "1" if that made the + // difference in the resulting rounding. Therefore, we + // preserve it, and OR (not ADD) it back in. The case + // that matters is when the eleven discarded bits are + // equal to 10000000001; that rounds up, and the 1 cannot + // be lost else it would round down if the LSB of the + // candidate mantissa is 0. + cmp := s.newValue2(cvttab.leq, types.Types[types.TBOOL], s.zeroVal(ft), x) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.Likely = ssa.BranchLikely + + bThen := s.f.NewBlock(ssa.BlockPlain) + bElse := s.f.NewBlock(ssa.BlockPlain) + bAfter := s.f.NewBlock(ssa.BlockPlain) + + b.AddEdgeTo(bThen) + s.startBlock(bThen) + a0 := s.newValue1(cvttab.cvt2F, tt, x) + s.vars[n] = a0 + s.endBlock() + bThen.AddEdgeTo(bAfter) + + b.AddEdgeTo(bElse) + s.startBlock(bElse) + one := cvttab.one(s, ft, 1) + y := s.newValue2(cvttab.and, ft, x, one) + z := s.newValue2(cvttab.rsh, ft, x, one) + z = s.newValue2(cvttab.or, ft, z, y) + a := s.newValue1(cvttab.cvt2F, tt, z) + a1 := s.newValue2(cvttab.add, tt, a, a) + s.vars[n] = a1 + s.endBlock() + bElse.AddEdgeTo(bAfter) + + s.startBlock(bAfter) + return s.variable(n, n.Type()) +} + +type u322fcvtTab struct { + cvtI2F, cvtF2F ssa.Op +} + +var u32_f64 = u322fcvtTab{ + cvtI2F: ssa.OpCvt32to64F, + cvtF2F: ssa.OpCopy, +} + +var u32_f32 = u322fcvtTab{ + cvtI2F: ssa.OpCvt32to32F, + cvtF2F: ssa.OpCvt64Fto32F, +} + +func (s *state) uint32Tofloat64(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.uint32Tofloat(&u32_f64, n, x, ft, tt) +} + +func (s *state) uint32Tofloat32(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.uint32Tofloat(&u32_f32, n, x, ft, tt) +} + +func (s *state) uint32Tofloat(cvttab *u322fcvtTab, n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + // if x >= 0 { + // result = floatY(x) + // } else { + // result = floatY(float64(x) + (1<<32)) + // } + cmp := s.newValue2(ssa.OpLeq32, types.Types[types.TBOOL], s.zeroVal(ft), x) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.Likely = ssa.BranchLikely + + bThen := s.f.NewBlock(ssa.BlockPlain) + bElse := s.f.NewBlock(ssa.BlockPlain) + bAfter := s.f.NewBlock(ssa.BlockPlain) + + b.AddEdgeTo(bThen) + s.startBlock(bThen) + a0 := s.newValue1(cvttab.cvtI2F, tt, x) + s.vars[n] = a0 + s.endBlock() + bThen.AddEdgeTo(bAfter) + + b.AddEdgeTo(bElse) + s.startBlock(bElse) + a1 := s.newValue1(ssa.OpCvt32to64F, types.Types[types.TFLOAT64], x) + twoToThe32 := s.constFloat64(types.Types[types.TFLOAT64], float64(1<<32)) + a2 := s.newValue2(ssa.OpAdd64F, types.Types[types.TFLOAT64], a1, twoToThe32) + a3 := s.newValue1(cvttab.cvtF2F, tt, a2) + + s.vars[n] = a3 + s.endBlock() + bElse.AddEdgeTo(bAfter) + + s.startBlock(bAfter) + return s.variable(n, n.Type()) +} + +// referenceTypeBuiltin generates code for the len/cap builtins for maps and channels. +func (s *state) referenceTypeBuiltin(n *ir.UnaryExpr, x *ssa.Value) *ssa.Value { + if !n.X.Type().IsMap() && !n.X.Type().IsChan() { + s.Fatalf("node must be a map or a channel") + } + // if n == nil { + // return 0 + // } else { + // // len + // return *((*int)n) + // // cap + // return *(((*int)n)+1) + // } + lenType := n.Type() + nilValue := s.constNil(types.Types[types.TUINTPTR]) + cmp := s.newValue2(ssa.OpEqPtr, types.Types[types.TBOOL], x, nilValue) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.Likely = ssa.BranchUnlikely + + bThen := s.f.NewBlock(ssa.BlockPlain) + bElse := s.f.NewBlock(ssa.BlockPlain) + bAfter := s.f.NewBlock(ssa.BlockPlain) + + // length/capacity of a nil map/chan is zero + b.AddEdgeTo(bThen) + s.startBlock(bThen) + s.vars[n] = s.zeroVal(lenType) + s.endBlock() + bThen.AddEdgeTo(bAfter) + + b.AddEdgeTo(bElse) + s.startBlock(bElse) + switch n.Op() { + case ir.OLEN: + // length is stored in the first word for map/chan + s.vars[n] = s.load(lenType, x) + case ir.OCAP: + // capacity is stored in the second word for chan + sw := s.newValue1I(ssa.OpOffPtr, lenType.PtrTo(), lenType.Size(), x) + s.vars[n] = s.load(lenType, sw) + default: + s.Fatalf("op must be OLEN or OCAP") + } + s.endBlock() + bElse.AddEdgeTo(bAfter) + + s.startBlock(bAfter) + return s.variable(n, lenType) +} + +type f2uCvtTab struct { + ltf, cvt2U, subf, or ssa.Op + floatValue func(*state, *types.Type, float64) *ssa.Value + intValue func(*state, *types.Type, int64) *ssa.Value + cutoff uint64 +} + +var f32_u64 = f2uCvtTab{ + ltf: ssa.OpLess32F, + cvt2U: ssa.OpCvt32Fto64, + subf: ssa.OpSub32F, + or: ssa.OpOr64, + floatValue: (*state).constFloat32, + intValue: (*state).constInt64, + cutoff: 1 << 63, +} + +var f64_u64 = f2uCvtTab{ + ltf: ssa.OpLess64F, + cvt2U: ssa.OpCvt64Fto64, + subf: ssa.OpSub64F, + or: ssa.OpOr64, + floatValue: (*state).constFloat64, + intValue: (*state).constInt64, + cutoff: 1 << 63, +} + +var f32_u32 = f2uCvtTab{ + ltf: ssa.OpLess32F, + cvt2U: ssa.OpCvt32Fto32, + subf: ssa.OpSub32F, + or: ssa.OpOr32, + floatValue: (*state).constFloat32, + intValue: func(s *state, t *types.Type, v int64) *ssa.Value { return s.constInt32(t, int32(v)) }, + cutoff: 1 << 31, +} + +var f64_u32 = f2uCvtTab{ + ltf: ssa.OpLess64F, + cvt2U: ssa.OpCvt64Fto32, + subf: ssa.OpSub64F, + or: ssa.OpOr32, + floatValue: (*state).constFloat64, + intValue: func(s *state, t *types.Type, v int64) *ssa.Value { return s.constInt32(t, int32(v)) }, + cutoff: 1 << 31, +} + +func (s *state) float32ToUint64(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.floatToUint(&f32_u64, n, x, ft, tt) +} +func (s *state) float64ToUint64(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.floatToUint(&f64_u64, n, x, ft, tt) +} + +func (s *state) float32ToUint32(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.floatToUint(&f32_u32, n, x, ft, tt) +} + +func (s *state) float64ToUint32(n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + return s.floatToUint(&f64_u32, n, x, ft, tt) +} + +func (s *state) floatToUint(cvttab *f2uCvtTab, n ir.Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value { + // cutoff:=1<<(intY_Size-1) + // if x < floatX(cutoff) { + // result = uintY(x) + // } else { + // y = x - floatX(cutoff) + // z = uintY(y) + // result = z | -(cutoff) + // } + cutoff := cvttab.floatValue(s, ft, float64(cvttab.cutoff)) + cmp := s.newValue2(cvttab.ltf, types.Types[types.TBOOL], x, cutoff) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.Likely = ssa.BranchLikely + + bThen := s.f.NewBlock(ssa.BlockPlain) + bElse := s.f.NewBlock(ssa.BlockPlain) + bAfter := s.f.NewBlock(ssa.BlockPlain) + + b.AddEdgeTo(bThen) + s.startBlock(bThen) + a0 := s.newValue1(cvttab.cvt2U, tt, x) + s.vars[n] = a0 + s.endBlock() + bThen.AddEdgeTo(bAfter) + + b.AddEdgeTo(bElse) + s.startBlock(bElse) + y := s.newValue2(cvttab.subf, ft, x, cutoff) + y = s.newValue1(cvttab.cvt2U, tt, y) + z := cvttab.intValue(s, tt, int64(-cvttab.cutoff)) + a1 := s.newValue2(cvttab.or, tt, y, z) + s.vars[n] = a1 + s.endBlock() + bElse.AddEdgeTo(bAfter) + + s.startBlock(bAfter) + return s.variable(n, n.Type()) +} + +// dottype generates SSA for a type assertion node. +// commaok indicates whether to panic or return a bool. +// If commaok is false, resok will be nil. +func (s *state) dottype(n *ir.TypeAssertExpr, commaok bool) (res, resok *ssa.Value) { + iface := s.expr(n.X) // input interface + target := s.reflectType(n.Type()) // target type + var targetItab *ssa.Value + if n.ITab != nil { + targetItab = s.expr(n.ITab) + } + return s.dottype1(n.Pos(), n.X.Type(), n.Type(), iface, nil, target, targetItab, commaok) +} + +func (s *state) dynamicDottype(n *ir.DynamicTypeAssertExpr, commaok bool) (res, resok *ssa.Value) { + iface := s.expr(n.X) + var source, target, targetItab *ssa.Value + if n.SrcRType != nil { + source = s.expr(n.SrcRType) + } + if !n.X.Type().IsEmptyInterface() && !n.Type().IsInterface() { + byteptr := s.f.Config.Types.BytePtr + targetItab = s.expr(n.ITab) + // TODO(mdempsky): Investigate whether compiling n.RType could be + // better than loading itab.typ. + target = s.load(byteptr, s.newValue1I(ssa.OpOffPtr, byteptr, int64(types.PtrSize), targetItab)) // itab.typ + } else { + target = s.expr(n.RType) + } + return s.dottype1(n.Pos(), n.X.Type(), n.Type(), iface, source, target, targetItab, commaok) +} + +// dottype1 implements a x.(T) operation. iface is the argument (x), dst is the type we're asserting to (T) +// and src is the type we're asserting from. +// source is the *runtime._type of src +// target is the *runtime._type of dst. +// If src is a nonempty interface and dst is not an interface, targetItab is an itab representing (dst, src). Otherwise it is nil. +// commaok is true if the caller wants a boolean success value. Otherwise, the generated code panics if the conversion fails. +func (s *state) dottype1(pos src.XPos, src, dst *types.Type, iface, source, target, targetItab *ssa.Value, commaok bool) (res, resok *ssa.Value) { + byteptr := s.f.Config.Types.BytePtr + if dst.IsInterface() { + if dst.IsEmptyInterface() { + // Converting to an empty interface. + // Input could be an empty or nonempty interface. + if base.Debug.TypeAssert > 0 { + base.WarnfAt(pos, "type assertion inlined") + } + + // Get itab/type field from input. + itab := s.newValue1(ssa.OpITab, byteptr, iface) + // Conversion succeeds iff that field is not nil. + cond := s.newValue2(ssa.OpNeqPtr, types.Types[types.TBOOL], itab, s.constNil(byteptr)) + + if src.IsEmptyInterface() && commaok { + // Converting empty interface to empty interface with ,ok is just a nil check. + return iface, cond + } + + // Branch on nilness. + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cond) + b.Likely = ssa.BranchLikely + bOk := s.f.NewBlock(ssa.BlockPlain) + bFail := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bOk) + b.AddEdgeTo(bFail) + + if !commaok { + // On failure, panic by calling panicnildottype. + s.startBlock(bFail) + s.rtcall(ir.Syms.Panicnildottype, false, nil, target) + + // On success, return (perhaps modified) input interface. + s.startBlock(bOk) + if src.IsEmptyInterface() { + res = iface // Use input interface unchanged. + return + } + // Load type out of itab, build interface with existing idata. + off := s.newValue1I(ssa.OpOffPtr, byteptr, int64(types.PtrSize), itab) + typ := s.load(byteptr, off) + idata := s.newValue1(ssa.OpIData, byteptr, iface) + res = s.newValue2(ssa.OpIMake, dst, typ, idata) + return + } + + s.startBlock(bOk) + // nonempty -> empty + // Need to load type from itab + off := s.newValue1I(ssa.OpOffPtr, byteptr, int64(types.PtrSize), itab) + s.vars[typVar] = s.load(byteptr, off) + s.endBlock() + + // itab is nil, might as well use that as the nil result. + s.startBlock(bFail) + s.vars[typVar] = itab + s.endBlock() + + // Merge point. + bEnd := s.f.NewBlock(ssa.BlockPlain) + bOk.AddEdgeTo(bEnd) + bFail.AddEdgeTo(bEnd) + s.startBlock(bEnd) + idata := s.newValue1(ssa.OpIData, byteptr, iface) + res = s.newValue2(ssa.OpIMake, dst, s.variable(typVar, byteptr), idata) + resok = cond + delete(s.vars, typVar) // no practical effect, just to indicate typVar is no longer live. + return + } + // converting to a nonempty interface needs a runtime call. + if base.Debug.TypeAssert > 0 { + base.WarnfAt(pos, "type assertion not inlined") + } + if !commaok { + fn := ir.Syms.AssertI2I + if src.IsEmptyInterface() { + fn = ir.Syms.AssertE2I + } + data := s.newValue1(ssa.OpIData, types.Types[types.TUNSAFEPTR], iface) + tab := s.newValue1(ssa.OpITab, byteptr, iface) + tab = s.rtcall(fn, true, []*types.Type{byteptr}, target, tab)[0] + return s.newValue2(ssa.OpIMake, dst, tab, data), nil + } + fn := ir.Syms.AssertI2I2 + if src.IsEmptyInterface() { + fn = ir.Syms.AssertE2I2 + } + res = s.rtcall(fn, true, []*types.Type{dst}, target, iface)[0] + resok = s.newValue2(ssa.OpNeqInter, types.Types[types.TBOOL], res, s.constInterface(dst)) + return + } + + if base.Debug.TypeAssert > 0 { + base.WarnfAt(pos, "type assertion inlined") + } + + // Converting to a concrete type. + direct := types.IsDirectIface(dst) + itab := s.newValue1(ssa.OpITab, byteptr, iface) // type word of interface + if base.Debug.TypeAssert > 0 { + base.WarnfAt(pos, "type assertion inlined") + } + var wantedFirstWord *ssa.Value + if src.IsEmptyInterface() { + // Looking for pointer to target type. + wantedFirstWord = target + } else { + // Looking for pointer to itab for target type and source interface. + wantedFirstWord = targetItab + } + + var tmp ir.Node // temporary for use with large types + var addr *ssa.Value // address of tmp + if commaok && !TypeOK(dst) { + // unSSAable type, use temporary. + // TODO: get rid of some of these temporaries. + tmp, addr = s.temp(pos, dst) + } + + cond := s.newValue2(ssa.OpEqPtr, types.Types[types.TBOOL], itab, wantedFirstWord) + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cond) + b.Likely = ssa.BranchLikely + + bOk := s.f.NewBlock(ssa.BlockPlain) + bFail := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(bOk) + b.AddEdgeTo(bFail) + + if !commaok { + // on failure, panic by calling panicdottype + s.startBlock(bFail) + taddr := source + if taddr == nil { + taddr = s.reflectType(src) + } + if src.IsEmptyInterface() { + s.rtcall(ir.Syms.PanicdottypeE, false, nil, itab, target, taddr) + } else { + s.rtcall(ir.Syms.PanicdottypeI, false, nil, itab, target, taddr) + } + + // on success, return data from interface + s.startBlock(bOk) + if direct { + return s.newValue1(ssa.OpIData, dst, iface), nil + } + p := s.newValue1(ssa.OpIData, types.NewPtr(dst), iface) + return s.load(dst, p), nil + } + + // commaok is the more complicated case because we have + // a control flow merge point. + bEnd := s.f.NewBlock(ssa.BlockPlain) + // Note that we need a new valVar each time (unlike okVar where we can + // reuse the variable) because it might have a different type every time. + valVar := ssaMarker("val") + + // type assertion succeeded + s.startBlock(bOk) + if tmp == nil { + if direct { + s.vars[valVar] = s.newValue1(ssa.OpIData, dst, iface) + } else { + p := s.newValue1(ssa.OpIData, types.NewPtr(dst), iface) + s.vars[valVar] = s.load(dst, p) + } + } else { + p := s.newValue1(ssa.OpIData, types.NewPtr(dst), iface) + s.move(dst, addr, p) + } + s.vars[okVar] = s.constBool(true) + s.endBlock() + bOk.AddEdgeTo(bEnd) + + // type assertion failed + s.startBlock(bFail) + if tmp == nil { + s.vars[valVar] = s.zeroVal(dst) + } else { + s.zero(dst, addr) + } + s.vars[okVar] = s.constBool(false) + s.endBlock() + bFail.AddEdgeTo(bEnd) + + // merge point + s.startBlock(bEnd) + if tmp == nil { + res = s.variable(valVar, dst) + delete(s.vars, valVar) // no practical effect, just to indicate typVar is no longer live. + } else { + res = s.load(dst, addr) + } + resok = s.variable(okVar, types.Types[types.TBOOL]) + delete(s.vars, okVar) // ditto + return res, resok +} + +// temp allocates a temp of type t at position pos +func (s *state) temp(pos src.XPos, t *types.Type) (*ir.Name, *ssa.Value) { + tmp := typecheck.TempAt(pos, s.curfn, t) + if t.HasPointers() { + s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, tmp, s.mem()) + } + addr := s.addr(tmp) + return tmp, addr +} + +// variable returns the value of a variable at the current location. +func (s *state) variable(n ir.Node, t *types.Type) *ssa.Value { + v := s.vars[n] + if v != nil { + return v + } + v = s.fwdVars[n] + if v != nil { + return v + } + + if s.curBlock == s.f.Entry { + // No variable should be live at entry. + s.f.Fatalf("value %v (%v) incorrectly live at entry", n, v) + } + // Make a FwdRef, which records a value that's live on block input. + // We'll find the matching definition as part of insertPhis. + v = s.newValue0A(ssa.OpFwdRef, t, fwdRefAux{N: n}) + s.fwdVars[n] = v + if n.Op() == ir.ONAME { + s.addNamedValue(n.(*ir.Name), v) + } + return v +} + +func (s *state) mem() *ssa.Value { + return s.variable(memVar, types.TypeMem) +} + +func (s *state) addNamedValue(n *ir.Name, v *ssa.Value) { + if n.Class == ir.Pxxx { + // Don't track our marker nodes (memVar etc.). + return + } + if ir.IsAutoTmp(n) { + // Don't track temporary variables. + return + } + if n.Class == ir.PPARAMOUT { + // Don't track named output values. This prevents return values + // from being assigned too early. See #14591 and #14762. TODO: allow this. + return + } + loc := ssa.LocalSlot{N: n, Type: n.Type(), Off: 0} + values, ok := s.f.NamedValues[loc] + if !ok { + s.f.Names = append(s.f.Names, &loc) + s.f.CanonicalLocalSlots[loc] = &loc + } + s.f.NamedValues[loc] = append(values, v) +} + +// Branch is an unresolved branch. +type Branch struct { + P *obj.Prog // branch instruction + B *ssa.Block // target +} + +// State contains state needed during Prog generation. +type State struct { + ABI obj.ABI + + pp *objw.Progs + + // Branches remembers all the branch instructions we've seen + // and where they would like to go. + Branches []Branch + + // JumpTables remembers all the jump tables we've seen. + JumpTables []*ssa.Block + + // bstart remembers where each block starts (indexed by block ID) + bstart []*obj.Prog + + maxarg int64 // largest frame size for arguments to calls made by the function + + // Map from GC safe points to liveness index, generated by + // liveness analysis. + livenessMap liveness.Map + + // partLiveArgs includes arguments that may be partially live, for which we + // need to generate instructions that spill the argument registers. + partLiveArgs map[*ir.Name]bool + + // lineRunStart records the beginning of the current run of instructions + // within a single block sharing the same line number + // Used to move statement marks to the beginning of such runs. + lineRunStart *obj.Prog + + // wasm: The number of values on the WebAssembly stack. This is only used as a safeguard. + OnWasmStackSkipped int +} + +func (s *State) FuncInfo() *obj.FuncInfo { + return s.pp.CurFunc.LSym.Func() +} + +// Prog appends a new Prog. +func (s *State) Prog(as obj.As) *obj.Prog { + p := s.pp.Prog(as) + if objw.LosesStmtMark(as) { + return p + } + // Float a statement start to the beginning of any same-line run. + // lineRunStart is reset at block boundaries, which appears to work well. + if s.lineRunStart == nil || s.lineRunStart.Pos.Line() != p.Pos.Line() { + s.lineRunStart = p + } else if p.Pos.IsStmt() == src.PosIsStmt { + s.lineRunStart.Pos = s.lineRunStart.Pos.WithIsStmt() + p.Pos = p.Pos.WithNotStmt() + } + return p +} + +// Pc returns the current Prog. +func (s *State) Pc() *obj.Prog { + return s.pp.Next +} + +// SetPos sets the current source position. +func (s *State) SetPos(pos src.XPos) { + s.pp.Pos = pos +} + +// Br emits a single branch instruction and returns the instruction. +// Not all architectures need the returned instruction, but otherwise +// the boilerplate is common to all. +func (s *State) Br(op obj.As, target *ssa.Block) *obj.Prog { + p := s.Prog(op) + p.To.Type = obj.TYPE_BRANCH + s.Branches = append(s.Branches, Branch{P: p, B: target}) + return p +} + +// DebugFriendlySetPosFrom adjusts Pos.IsStmt subject to heuristics +// that reduce "jumpy" line number churn when debugging. +// Spill/fill/copy instructions from the register allocator, +// phi functions, and instructions with a no-pos position +// are examples of instructions that can cause churn. +func (s *State) DebugFriendlySetPosFrom(v *ssa.Value) { + switch v.Op { + case ssa.OpPhi, ssa.OpCopy, ssa.OpLoadReg, ssa.OpStoreReg: + // These are not statements + s.SetPos(v.Pos.WithNotStmt()) + default: + p := v.Pos + if p != src.NoXPos { + // If the position is defined, update the position. + // Also convert default IsStmt to NotStmt; only + // explicit statement boundaries should appear + // in the generated code. + if p.IsStmt() != src.PosIsStmt { + if s.pp.Pos.IsStmt() == src.PosIsStmt && s.pp.Pos.SameFileAndLine(p) { + // If s.pp.Pos already has a statement mark, then it was set here (below) for + // the previous value. If an actual instruction had been emitted for that + // value, then the statement mark would have been reset. Since the statement + // mark of s.pp.Pos was not reset, this position (file/line) still needs a + // statement mark on an instruction. If file and line for this value are + // the same as the previous value, then the first instruction for this + // value will work to take the statement mark. Return early to avoid + // resetting the statement mark. + // + // The reset of s.pp.Pos occurs in (*Progs).Prog() -- if it emits + // an instruction, and the instruction's statement mark was set, + // and it is not one of the LosesStmtMark instructions, + // then Prog() resets the statement mark on the (*Progs).Pos. + return + } + p = p.WithNotStmt() + // Calls use the pos attached to v, but copy the statement mark from State + } + s.SetPos(p) + } else { + s.SetPos(s.pp.Pos.WithNotStmt()) + } + } +} + +// emit argument info (locations on stack) for traceback. +func emitArgInfo(e *ssafn, f *ssa.Func, pp *objw.Progs) { + ft := e.curfn.Type() + if ft.NumRecvs() == 0 && ft.NumParams() == 0 { + return + } + + x := EmitArgInfo(e.curfn, f.OwnAux.ABIInfo()) + x.Set(obj.AttrContentAddressable, true) + e.curfn.LSym.Func().ArgInfo = x + + // Emit a funcdata pointing at the arg info data. + p := pp.Prog(obj.AFUNCDATA) + p.From.SetConst(rtabi.FUNCDATA_ArgInfo) + p.To.Type = obj.TYPE_MEM + p.To.Name = obj.NAME_EXTERN + p.To.Sym = x +} + +// emit argument info (locations on stack) of f for traceback. +func EmitArgInfo(f *ir.Func, abiInfo *abi.ABIParamResultInfo) *obj.LSym { + x := base.Ctxt.Lookup(fmt.Sprintf("%s.arginfo%d", f.LSym.Name, f.ABI)) + // NOTE: do not set ContentAddressable here. This may be referenced from + // assembly code by name (in this case f is a declaration). + // Instead, set it in emitArgInfo above. + + PtrSize := int64(types.PtrSize) + uintptrTyp := types.Types[types.TUINTPTR] + + isAggregate := func(t *types.Type) bool { + return t.IsStruct() || t.IsArray() || t.IsComplex() || t.IsInterface() || t.IsString() || t.IsSlice() + } + + // Populate the data. + // The data is a stream of bytes, which contains the offsets and sizes of the + // non-aggregate arguments or non-aggregate fields/elements of aggregate-typed + // arguments, along with special "operators". Specifically, + // - for each non-aggrgate arg/field/element, its offset from FP (1 byte) and + // size (1 byte) + // - special operators: + // - 0xff - end of sequence + // - 0xfe - print { (at the start of an aggregate-typed argument) + // - 0xfd - print } (at the end of an aggregate-typed argument) + // - 0xfc - print ... (more args/fields/elements) + // - 0xfb - print _ (offset too large) + // These constants need to be in sync with runtime.traceback.go:printArgs. + const ( + _endSeq = 0xff + _startAgg = 0xfe + _endAgg = 0xfd + _dotdotdot = 0xfc + _offsetTooLarge = 0xfb + _special = 0xf0 // above this are operators, below this are ordinary offsets + ) + + const ( + limit = 10 // print no more than 10 args/components + maxDepth = 5 // no more than 5 layers of nesting + + // maxLen is a (conservative) upper bound of the byte stream length. For + // each arg/component, it has no more than 2 bytes of data (size, offset), + // and no more than one {, }, ... at each level (it cannot have both the + // data and ... unless it is the last one, just be conservative). Plus 1 + // for _endSeq. + maxLen = (maxDepth*3+2)*limit + 1 + ) + + wOff := 0 + n := 0 + writebyte := func(o uint8) { wOff = objw.Uint8(x, wOff, o) } + + // Write one non-aggrgate arg/field/element. + write1 := func(sz, offset int64) { + if offset >= _special { + writebyte(_offsetTooLarge) + } else { + writebyte(uint8(offset)) + writebyte(uint8(sz)) + } + n++ + } + + // Visit t recursively and write it out. + // Returns whether to continue visiting. + var visitType func(baseOffset int64, t *types.Type, depth int) bool + visitType = func(baseOffset int64, t *types.Type, depth int) bool { + if n >= limit { + writebyte(_dotdotdot) + return false + } + if !isAggregate(t) { + write1(t.Size(), baseOffset) + return true + } + writebyte(_startAgg) + depth++ + if depth >= maxDepth { + writebyte(_dotdotdot) + writebyte(_endAgg) + n++ + return true + } + switch { + case t.IsInterface(), t.IsString(): + _ = visitType(baseOffset, uintptrTyp, depth) && + visitType(baseOffset+PtrSize, uintptrTyp, depth) + case t.IsSlice(): + _ = visitType(baseOffset, uintptrTyp, depth) && + visitType(baseOffset+PtrSize, uintptrTyp, depth) && + visitType(baseOffset+PtrSize*2, uintptrTyp, depth) + case t.IsComplex(): + _ = visitType(baseOffset, types.FloatForComplex(t), depth) && + visitType(baseOffset+t.Size()/2, types.FloatForComplex(t), depth) + case t.IsArray(): + if t.NumElem() == 0 { + n++ // {} counts as a component + break + } + for i := int64(0); i < t.NumElem(); i++ { + if !visitType(baseOffset, t.Elem(), depth) { + break + } + baseOffset += t.Elem().Size() + } + case t.IsStruct(): + if t.NumFields() == 0 { + n++ // {} counts as a component + break + } + for _, field := range t.Fields().Slice() { + if !visitType(baseOffset+field.Offset, field.Type, depth) { + break + } + } + } + writebyte(_endAgg) + return true + } + + start := 0 + if strings.Contains(f.LSym.Name, "[") { + // Skip the dictionary argument - it is implicit and the user doesn't need to see it. + start = 1 + } + + for _, a := range abiInfo.InParams()[start:] { + if !visitType(a.FrameOffset(abiInfo), a.Type, 0) { + break + } + } + writebyte(_endSeq) + if wOff > maxLen { + base.Fatalf("ArgInfo too large") + } + + return x +} + +// for wrapper, emit info of wrapped function. +func emitWrappedFuncInfo(e *ssafn, pp *objw.Progs) { + if base.Ctxt.Flag_linkshared { + // Relative reference (SymPtrOff) to another shared object doesn't work. + // Unfortunate. + return + } + + wfn := e.curfn.WrappedFunc + if wfn == nil { + return + } + + wsym := wfn.Linksym() + x := base.Ctxt.LookupInit(fmt.Sprintf("%s.wrapinfo", wsym.Name), func(x *obj.LSym) { + objw.SymPtrOff(x, 0, wsym) + x.Set(obj.AttrContentAddressable, true) + }) + e.curfn.LSym.Func().WrapInfo = x + + // Emit a funcdata pointing at the wrap info data. + p := pp.Prog(obj.AFUNCDATA) + p.From.SetConst(rtabi.FUNCDATA_WrapInfo) + p.To.Type = obj.TYPE_MEM + p.To.Name = obj.NAME_EXTERN + p.To.Sym = x +} + +// genssa appends entries to pp for each instruction in f. +func genssa(f *ssa.Func, pp *objw.Progs) { + var s State + s.ABI = f.OwnAux.Fn.ABI() + + e := f.Frontend().(*ssafn) + + s.livenessMap, s.partLiveArgs = liveness.Compute(e.curfn, f, e.stkptrsize, pp) + emitArgInfo(e, f, pp) + argLiveBlockMap, argLiveValueMap := liveness.ArgLiveness(e.curfn, f, pp) + + openDeferInfo := e.curfn.LSym.Func().OpenCodedDeferInfo + if openDeferInfo != nil { + // This function uses open-coded defers -- write out the funcdata + // info that we computed at the end of genssa. + p := pp.Prog(obj.AFUNCDATA) + p.From.SetConst(rtabi.FUNCDATA_OpenCodedDeferInfo) + p.To.Type = obj.TYPE_MEM + p.To.Name = obj.NAME_EXTERN + p.To.Sym = openDeferInfo + } + + emitWrappedFuncInfo(e, pp) + + // Remember where each block starts. + s.bstart = make([]*obj.Prog, f.NumBlocks()) + s.pp = pp + var progToValue map[*obj.Prog]*ssa.Value + var progToBlock map[*obj.Prog]*ssa.Block + var valueToProgAfter []*obj.Prog // The first Prog following computation of a value v; v is visible at this point. + gatherPrintInfo := f.PrintOrHtmlSSA || ssa.GenssaDump[f.Name] + if gatherPrintInfo { + progToValue = make(map[*obj.Prog]*ssa.Value, f.NumValues()) + progToBlock = make(map[*obj.Prog]*ssa.Block, f.NumBlocks()) + f.Logf("genssa %s\n", f.Name) + progToBlock[s.pp.Next] = f.Blocks[0] + } + + if base.Ctxt.Flag_locationlists { + if cap(f.Cache.ValueToProgAfter) < f.NumValues() { + f.Cache.ValueToProgAfter = make([]*obj.Prog, f.NumValues()) + } + valueToProgAfter = f.Cache.ValueToProgAfter[:f.NumValues()] + for i := range valueToProgAfter { + valueToProgAfter[i] = nil + } + } + + // If the very first instruction is not tagged as a statement, + // debuggers may attribute it to previous function in program. + firstPos := src.NoXPos + for _, v := range f.Entry.Values { + if v.Pos.IsStmt() == src.PosIsStmt && v.Op != ssa.OpArg && v.Op != ssa.OpArgIntReg && v.Op != ssa.OpArgFloatReg && v.Op != ssa.OpLoadReg && v.Op != ssa.OpStoreReg { + firstPos = v.Pos + v.Pos = firstPos.WithDefaultStmt() + break + } + } + + // inlMarks has an entry for each Prog that implements an inline mark. + // It maps from that Prog to the global inlining id of the inlined body + // which should unwind to this Prog's location. + var inlMarks map[*obj.Prog]int32 + var inlMarkList []*obj.Prog + + // inlMarksByPos maps from a (column 1) source position to the set of + // Progs that are in the set above and have that source position. + var inlMarksByPos map[src.XPos][]*obj.Prog + + var argLiveIdx int = -1 // argument liveness info index + + // Emit basic blocks + for i, b := range f.Blocks { + s.bstart[b.ID] = s.pp.Next + s.lineRunStart = nil + s.SetPos(s.pp.Pos.WithNotStmt()) // It needs a non-empty Pos, but cannot be a statement boundary (yet). + + // Attach a "default" liveness info. Normally this will be + // overwritten in the Values loop below for each Value. But + // for an empty block this will be used for its control + // instruction. We won't use the actual liveness map on a + // control instruction. Just mark it something that is + // preemptible, unless this function is "all unsafe", or + // the empty block is in a write barrier. + unsafe := liveness.IsUnsafe(f) + if b.Kind == ssa.BlockPlain { + // Empty blocks that are part of write barriers need + // to have their control instructions marked unsafe. + c := b.Succs[0].Block() + for _, v := range c.Values { + if v.Op == ssa.OpWBend { + unsafe = true + break + } + } + } + s.pp.NextLive = objw.LivenessIndex{StackMapIndex: -1, IsUnsafePoint: unsafe} + + if idx, ok := argLiveBlockMap[b.ID]; ok && idx != argLiveIdx { + argLiveIdx = idx + p := s.pp.Prog(obj.APCDATA) + p.From.SetConst(rtabi.PCDATA_ArgLiveIndex) + p.To.SetConst(int64(idx)) + } + + // Emit values in block + Arch.SSAMarkMoves(&s, b) + for _, v := range b.Values { + x := s.pp.Next + s.DebugFriendlySetPosFrom(v) + + if v.Op.ResultInArg0() && v.ResultReg() != v.Args[0].Reg() { + v.Fatalf("input[0] and output not in same register %s", v.LongString()) + } + + switch v.Op { + case ssa.OpInitMem: + // memory arg needs no code + case ssa.OpArg: + // input args need no code + case ssa.OpSP, ssa.OpSB: + // nothing to do + case ssa.OpSelect0, ssa.OpSelect1, ssa.OpSelectN, ssa.OpMakeResult: + // nothing to do + case ssa.OpGetG: + // nothing to do when there's a g register, + // and checkLower complains if there's not + case ssa.OpVarDef, ssa.OpVarLive, ssa.OpKeepAlive, ssa.OpWBend: + // nothing to do; already used by liveness + case ssa.OpPhi: + CheckLoweredPhi(v) + case ssa.OpConvert: + // nothing to do; no-op conversion for liveness + if v.Args[0].Reg() != v.Reg() { + v.Fatalf("OpConvert should be a no-op: %s; %s", v.Args[0].LongString(), v.LongString()) + } + case ssa.OpInlMark: + p := Arch.Ginsnop(s.pp) + if inlMarks == nil { + inlMarks = map[*obj.Prog]int32{} + inlMarksByPos = map[src.XPos][]*obj.Prog{} + } + inlMarks[p] = v.AuxInt32() + inlMarkList = append(inlMarkList, p) + pos := v.Pos.AtColumn1() + inlMarksByPos[pos] = append(inlMarksByPos[pos], p) + firstPos = src.NoXPos + + default: + // Special case for first line in function; move it to the start (which cannot be a register-valued instruction) + if firstPos != src.NoXPos && v.Op != ssa.OpArgIntReg && v.Op != ssa.OpArgFloatReg && v.Op != ssa.OpLoadReg && v.Op != ssa.OpStoreReg { + s.SetPos(firstPos) + firstPos = src.NoXPos + } + // Attach this safe point to the next + // instruction. + s.pp.NextLive = s.livenessMap.Get(v) + + // let the backend handle it + Arch.SSAGenValue(&s, v) + } + + if idx, ok := argLiveValueMap[v.ID]; ok && idx != argLiveIdx { + argLiveIdx = idx + p := s.pp.Prog(obj.APCDATA) + p.From.SetConst(rtabi.PCDATA_ArgLiveIndex) + p.To.SetConst(int64(idx)) + } + + if base.Ctxt.Flag_locationlists { + valueToProgAfter[v.ID] = s.pp.Next + } + + if gatherPrintInfo { + for ; x != s.pp.Next; x = x.Link { + progToValue[x] = v + } + } + } + // If this is an empty infinite loop, stick a hardware NOP in there so that debuggers are less confused. + if s.bstart[b.ID] == s.pp.Next && len(b.Succs) == 1 && b.Succs[0].Block() == b { + p := Arch.Ginsnop(s.pp) + p.Pos = p.Pos.WithIsStmt() + if b.Pos == src.NoXPos { + b.Pos = p.Pos // It needs a file, otherwise a no-file non-zero line causes confusion. See #35652. + if b.Pos == src.NoXPos { + b.Pos = pp.Text.Pos // Sometimes p.Pos is empty. See #35695. + } + } + b.Pos = b.Pos.WithBogusLine() // Debuggers are not good about infinite loops, force a change in line number + } + // Emit control flow instructions for block + var next *ssa.Block + if i < len(f.Blocks)-1 && base.Flag.N == 0 { + // If -N, leave next==nil so every block with successors + // ends in a JMP (except call blocks - plive doesn't like + // select{send,recv} followed by a JMP call). Helps keep + // line numbers for otherwise empty blocks. + next = f.Blocks[i+1] + } + x := s.pp.Next + s.SetPos(b.Pos) + Arch.SSAGenBlock(&s, b, next) + if gatherPrintInfo { + for ; x != s.pp.Next; x = x.Link { + progToBlock[x] = b + } + } + } + if f.Blocks[len(f.Blocks)-1].Kind == ssa.BlockExit { + // We need the return address of a panic call to + // still be inside the function in question. So if + // it ends in a call which doesn't return, add a + // nop (which will never execute) after the call. + Arch.Ginsnop(pp) + } + if openDeferInfo != nil { + // When doing open-coded defers, generate a disconnected call to + // deferreturn and a return. This will be used to during panic + // recovery to unwind the stack and return back to the runtime. + s.pp.NextLive = s.livenessMap.DeferReturn + p := pp.Prog(obj.ACALL) + p.To.Type = obj.TYPE_MEM + p.To.Name = obj.NAME_EXTERN + p.To.Sym = ir.Syms.Deferreturn + + // Load results into registers. So when a deferred function + // recovers a panic, it will return to caller with right results. + // The results are already in memory, because they are not SSA'd + // when the function has defers (see canSSAName). + for _, o := range f.OwnAux.ABIInfo().OutParams() { + n := o.Name.(*ir.Name) + rts, offs := o.RegisterTypesAndOffsets() + for i := range o.Registers { + Arch.LoadRegResult(&s, f, rts[i], ssa.ObjRegForAbiReg(o.Registers[i], f.Config), n, offs[i]) + } + } + + pp.Prog(obj.ARET) + } + + if inlMarks != nil { + hasCall := false + + // We have some inline marks. Try to find other instructions we're + // going to emit anyway, and use those instructions instead of the + // inline marks. + for p := pp.Text; p != nil; p = p.Link { + if p.As == obj.ANOP || p.As == obj.AFUNCDATA || p.As == obj.APCDATA || p.As == obj.ATEXT || p.As == obj.APCALIGN || Arch.LinkArch.Family == sys.Wasm { + // Don't use 0-sized instructions as inline marks, because we need + // to identify inline mark instructions by pc offset. + // (Some of these instructions are sometimes zero-sized, sometimes not. + // We must not use anything that even might be zero-sized.) + // TODO: are there others? + continue + } + if _, ok := inlMarks[p]; ok { + // Don't use inline marks themselves. We don't know + // whether they will be zero-sized or not yet. + continue + } + if p.As == obj.ACALL || p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO { + hasCall = true + } + pos := p.Pos.AtColumn1() + s := inlMarksByPos[pos] + if len(s) == 0 { + continue + } + for _, m := range s { + // We found an instruction with the same source position as + // some of the inline marks. + // Use this instruction instead. + p.Pos = p.Pos.WithIsStmt() // promote position to a statement + pp.CurFunc.LSym.Func().AddInlMark(p, inlMarks[m]) + // Make the inline mark a real nop, so it doesn't generate any code. + m.As = obj.ANOP + m.Pos = src.NoXPos + m.From = obj.Addr{} + m.To = obj.Addr{} + } + delete(inlMarksByPos, pos) + } + // Any unmatched inline marks now need to be added to the inlining tree (and will generate a nop instruction). + for _, p := range inlMarkList { + if p.As != obj.ANOP { + pp.CurFunc.LSym.Func().AddInlMark(p, inlMarks[p]) + } + } + + if e.stksize == 0 && !hasCall { + // Frameless leaf function. It doesn't need any preamble, + // so make sure its first instruction isn't from an inlined callee. + // If it is, add a nop at the start of the function with a position + // equal to the start of the function. + // This ensures that runtime.FuncForPC(uintptr(reflect.ValueOf(fn).Pointer())).Name() + // returns the right answer. See issue 58300. + for p := pp.Text; p != nil; p = p.Link { + if p.As == obj.AFUNCDATA || p.As == obj.APCDATA || p.As == obj.ATEXT || p.As == obj.ANOP { + continue + } + if base.Ctxt.PosTable.Pos(p.Pos).Base().InliningIndex() >= 0 { + // Make a real (not 0-sized) nop. + nop := Arch.Ginsnop(pp) + nop.Pos = e.curfn.Pos().WithIsStmt() + + // Unfortunately, Ginsnop puts the instruction at the + // end of the list. Move it up to just before p. + + // Unlink from the current list. + for x := pp.Text; x != nil; x = x.Link { + if x.Link == nop { + x.Link = nop.Link + break + } + } + // Splice in right before p. + for x := pp.Text; x != nil; x = x.Link { + if x.Link == p { + nop.Link = p + x.Link = nop + break + } + } + } + break + } + } + } + + if base.Ctxt.Flag_locationlists { + var debugInfo *ssa.FuncDebug + debugInfo = e.curfn.DebugInfo.(*ssa.FuncDebug) + if e.curfn.ABI == obj.ABIInternal && base.Flag.N != 0 { + ssa.BuildFuncDebugNoOptimized(base.Ctxt, f, base.Debug.LocationLists > 1, StackOffset, debugInfo) + } else { + ssa.BuildFuncDebug(base.Ctxt, f, base.Debug.LocationLists, StackOffset, debugInfo) + } + bstart := s.bstart + idToIdx := make([]int, f.NumBlocks()) + for i, b := range f.Blocks { + idToIdx[b.ID] = i + } + // Note that at this moment, Prog.Pc is a sequence number; it's + // not a real PC until after assembly, so this mapping has to + // be done later. + debugInfo.GetPC = func(b, v ssa.ID) int64 { + switch v { + case ssa.BlockStart.ID: + if b == f.Entry.ID { + return 0 // Start at the very beginning, at the assembler-generated prologue. + // this should only happen for function args (ssa.OpArg) + } + return bstart[b].Pc + case ssa.BlockEnd.ID: + blk := f.Blocks[idToIdx[b]] + nv := len(blk.Values) + return valueToProgAfter[blk.Values[nv-1].ID].Pc + case ssa.FuncEnd.ID: + return e.curfn.LSym.Size + default: + return valueToProgAfter[v].Pc + } + } + } + + // Resolve branches, and relax DefaultStmt into NotStmt + for _, br := range s.Branches { + br.P.To.SetTarget(s.bstart[br.B.ID]) + if br.P.Pos.IsStmt() != src.PosIsStmt { + br.P.Pos = br.P.Pos.WithNotStmt() + } else if v0 := br.B.FirstPossibleStmtValue(); v0 != nil && v0.Pos.Line() == br.P.Pos.Line() && v0.Pos.IsStmt() == src.PosIsStmt { + br.P.Pos = br.P.Pos.WithNotStmt() + } + + } + + // Resolve jump table destinations. + for _, jt := range s.JumpTables { + // Convert from *Block targets to *Prog targets. + targets := make([]*obj.Prog, len(jt.Succs)) + for i, e := range jt.Succs { + targets[i] = s.bstart[e.Block().ID] + } + // Add to list of jump tables to be resolved at assembly time. + // The assembler converts from *Prog entries to absolute addresses + // once it knows instruction byte offsets. + fi := pp.CurFunc.LSym.Func() + fi.JumpTables = append(fi.JumpTables, obj.JumpTable{Sym: jt.Aux.(*obj.LSym), Targets: targets}) + } + + if e.log { // spew to stdout + filename := "" + for p := pp.Text; p != nil; p = p.Link { + if p.Pos.IsKnown() && p.InnermostFilename() != filename { + filename = p.InnermostFilename() + f.Logf("# %s\n", filename) + } + + var s string + if v, ok := progToValue[p]; ok { + s = v.String() + } else if b, ok := progToBlock[p]; ok { + s = b.String() + } else { + s = " " // most value and branch strings are 2-3 characters long + } + f.Logf(" %-6s\t%.5d (%s)\t%s\n", s, p.Pc, p.InnermostLineNumber(), p.InstructionString()) + } + } + if f.HTMLWriter != nil { // spew to ssa.html + var buf strings.Builder + buf.WriteString("<code>") + buf.WriteString("<dl class=\"ssa-gen\">") + filename := "" + for p := pp.Text; p != nil; p = p.Link { + // Don't spam every line with the file name, which is often huge. + // Only print changes, and "unknown" is not a change. + if p.Pos.IsKnown() && p.InnermostFilename() != filename { + filename = p.InnermostFilename() + buf.WriteString("<dt class=\"ssa-prog-src\"></dt><dd class=\"ssa-prog\">") + buf.WriteString(html.EscapeString("# " + filename)) + buf.WriteString("</dd>") + } + + buf.WriteString("<dt class=\"ssa-prog-src\">") + if v, ok := progToValue[p]; ok { + buf.WriteString(v.HTML()) + } else if b, ok := progToBlock[p]; ok { + buf.WriteString("<b>" + b.HTML() + "</b>") + } + buf.WriteString("</dt>") + buf.WriteString("<dd class=\"ssa-prog\">") + fmt.Fprintf(&buf, "%.5d <span class=\"l%v line-number\">(%s)</span> %s", p.Pc, p.InnermostLineNumber(), p.InnermostLineNumberHTML(), html.EscapeString(p.InstructionString())) + buf.WriteString("</dd>") + } + buf.WriteString("</dl>") + buf.WriteString("</code>") + f.HTMLWriter.WriteColumn("genssa", "genssa", "ssa-prog", buf.String()) + } + if ssa.GenssaDump[f.Name] { + fi := f.DumpFileForPhase("genssa") + if fi != nil { + + // inliningDiffers if any filename changes or if any line number except the innermost (last index) changes. + inliningDiffers := func(a, b []src.Pos) bool { + if len(a) != len(b) { + return true + } + for i := range a { + if a[i].Filename() != b[i].Filename() { + return true + } + if i != len(a)-1 && a[i].Line() != b[i].Line() { + return true + } + } + return false + } + + var allPosOld []src.Pos + var allPos []src.Pos + + for p := pp.Text; p != nil; p = p.Link { + if p.Pos.IsKnown() { + allPos = allPos[:0] + p.Ctxt.AllPos(p.Pos, func(pos src.Pos) { allPos = append(allPos, pos) }) + if inliningDiffers(allPos, allPosOld) { + for _, pos := range allPos { + fmt.Fprintf(fi, "# %s:%d\n", pos.Filename(), pos.Line()) + } + allPos, allPosOld = allPosOld, allPos // swap, not copy, so that they do not share slice storage. + } + } + + var s string + if v, ok := progToValue[p]; ok { + s = v.String() + } else if b, ok := progToBlock[p]; ok { + s = b.String() + } else { + s = " " // most value and branch strings are 2-3 characters long + } + fmt.Fprintf(fi, " %-6s\t%.5d %s\t%s\n", s, p.Pc, ssa.StmtString(p.Pos), p.InstructionString()) + } + fi.Close() + } + } + + defframe(&s, e, f) + + f.HTMLWriter.Close() + f.HTMLWriter = nil +} + +func defframe(s *State, e *ssafn, f *ssa.Func) { + pp := s.pp + + s.maxarg = types.RoundUp(s.maxarg, e.stkalign) + frame := s.maxarg + e.stksize + if Arch.PadFrame != nil { + frame = Arch.PadFrame(frame) + } + + // Fill in argument and frame size. + pp.Text.To.Type = obj.TYPE_TEXTSIZE + pp.Text.To.Val = int32(types.RoundUp(f.OwnAux.ArgWidth(), int64(types.RegSize))) + pp.Text.To.Offset = frame + + p := pp.Text + + // Insert code to spill argument registers if the named slot may be partially + // live. That is, the named slot is considered live by liveness analysis, + // (because a part of it is live), but we may not spill all parts into the + // slot. This can only happen with aggregate-typed arguments that are SSA-able + // and not address-taken (for non-SSA-able or address-taken arguments we always + // spill upfront). + // Note: spilling is unnecessary in the -N/no-optimize case, since all values + // will be considered non-SSAable and spilled up front. + // TODO(register args) Make liveness more fine-grained to that partial spilling is okay. + if f.OwnAux.ABIInfo().InRegistersUsed() != 0 && base.Flag.N == 0 { + // First, see if it is already spilled before it may be live. Look for a spill + // in the entry block up to the first safepoint. + type nameOff struct { + n *ir.Name + off int64 + } + partLiveArgsSpilled := make(map[nameOff]bool) + for _, v := range f.Entry.Values { + if v.Op.IsCall() { + break + } + if v.Op != ssa.OpStoreReg || v.Args[0].Op != ssa.OpArgIntReg { + continue + } + n, off := ssa.AutoVar(v) + if n.Class != ir.PPARAM || n.Addrtaken() || !TypeOK(n.Type()) || !s.partLiveArgs[n] { + continue + } + partLiveArgsSpilled[nameOff{n, off}] = true + } + + // Then, insert code to spill registers if not already. + for _, a := range f.OwnAux.ABIInfo().InParams() { + n, ok := a.Name.(*ir.Name) + if !ok || n.Addrtaken() || !TypeOK(n.Type()) || !s.partLiveArgs[n] || len(a.Registers) <= 1 { + continue + } + rts, offs := a.RegisterTypesAndOffsets() + for i := range a.Registers { + if !rts[i].HasPointers() { + continue + } + if partLiveArgsSpilled[nameOff{n, offs[i]}] { + continue // already spilled + } + reg := ssa.ObjRegForAbiReg(a.Registers[i], f.Config) + p = Arch.SpillArgReg(pp, p, f, rts[i], reg, n, offs[i]) + } + } + } + + // Insert code to zero ambiguously live variables so that the + // garbage collector only sees initialized values when it + // looks for pointers. + var lo, hi int64 + + // Opaque state for backend to use. Current backends use it to + // keep track of which helper registers have been zeroed. + var state uint32 + + // Iterate through declarations. Autos are sorted in decreasing + // frame offset order. + for _, n := range e.curfn.Dcl { + if !n.Needzero() { + continue + } + if n.Class != ir.PAUTO { + e.Fatalf(n.Pos(), "needzero class %d", n.Class) + } + if n.Type().Size()%int64(types.PtrSize) != 0 || n.FrameOffset()%int64(types.PtrSize) != 0 || n.Type().Size() == 0 { + e.Fatalf(n.Pos(), "var %L has size %d offset %d", n, n.Type().Size(), n.Offset_) + } + + if lo != hi && n.FrameOffset()+n.Type().Size() >= lo-int64(2*types.RegSize) { + // Merge with range we already have. + lo = n.FrameOffset() + continue + } + + // Zero old range + p = Arch.ZeroRange(pp, p, frame+lo, hi-lo, &state) + + // Set new range. + lo = n.FrameOffset() + hi = lo + n.Type().Size() + } + + // Zero final range. + Arch.ZeroRange(pp, p, frame+lo, hi-lo, &state) +} + +// For generating consecutive jump instructions to model a specific branching +type IndexJump struct { + Jump obj.As + Index int +} + +func (s *State) oneJump(b *ssa.Block, jump *IndexJump) { + p := s.Br(jump.Jump, b.Succs[jump.Index].Block()) + p.Pos = b.Pos +} + +// CombJump generates combinational instructions (2 at present) for a block jump, +// thereby the behaviour of non-standard condition codes could be simulated +func (s *State) CombJump(b, next *ssa.Block, jumps *[2][2]IndexJump) { + switch next { + case b.Succs[0].Block(): + s.oneJump(b, &jumps[0][0]) + s.oneJump(b, &jumps[0][1]) + case b.Succs[1].Block(): + s.oneJump(b, &jumps[1][0]) + s.oneJump(b, &jumps[1][1]) + default: + var q *obj.Prog + if b.Likely != ssa.BranchUnlikely { + s.oneJump(b, &jumps[1][0]) + s.oneJump(b, &jumps[1][1]) + q = s.Br(obj.AJMP, b.Succs[1].Block()) + } else { + s.oneJump(b, &jumps[0][0]) + s.oneJump(b, &jumps[0][1]) + q = s.Br(obj.AJMP, b.Succs[0].Block()) + } + q.Pos = b.Pos + } +} + +// AddAux adds the offset in the aux fields (AuxInt and Aux) of v to a. +func AddAux(a *obj.Addr, v *ssa.Value) { + AddAux2(a, v, v.AuxInt) +} +func AddAux2(a *obj.Addr, v *ssa.Value, offset int64) { + if a.Type != obj.TYPE_MEM && a.Type != obj.TYPE_ADDR { + v.Fatalf("bad AddAux addr %v", a) + } + // add integer offset + a.Offset += offset + + // If no additional symbol offset, we're done. + if v.Aux == nil { + return + } + // Add symbol's offset from its base register. + switch n := v.Aux.(type) { + case *ssa.AuxCall: + a.Name = obj.NAME_EXTERN + a.Sym = n.Fn + case *obj.LSym: + a.Name = obj.NAME_EXTERN + a.Sym = n + case *ir.Name: + if n.Class == ir.PPARAM || (n.Class == ir.PPARAMOUT && !n.IsOutputParamInRegisters()) { + a.Name = obj.NAME_PARAM + a.Sym = ir.Orig(n).(*ir.Name).Linksym() + a.Offset += n.FrameOffset() + break + } + a.Name = obj.NAME_AUTO + if n.Class == ir.PPARAMOUT { + a.Sym = ir.Orig(n).(*ir.Name).Linksym() + } else { + a.Sym = n.Linksym() + } + a.Offset += n.FrameOffset() + default: + v.Fatalf("aux in %s not implemented %#v", v, v.Aux) + } +} + +// extendIndex extends v to a full int width. +// panic with the given kind if v does not fit in an int (only on 32-bit archs). +func (s *state) extendIndex(idx, len *ssa.Value, kind ssa.BoundsKind, bounded bool) *ssa.Value { + size := idx.Type.Size() + if size == s.config.PtrSize { + return idx + } + if size > s.config.PtrSize { + // truncate 64-bit indexes on 32-bit pointer archs. Test the + // high word and branch to out-of-bounds failure if it is not 0. + var lo *ssa.Value + if idx.Type.IsSigned() { + lo = s.newValue1(ssa.OpInt64Lo, types.Types[types.TINT], idx) + } else { + lo = s.newValue1(ssa.OpInt64Lo, types.Types[types.TUINT], idx) + } + if bounded || base.Flag.B != 0 { + return lo + } + bNext := s.f.NewBlock(ssa.BlockPlain) + bPanic := s.f.NewBlock(ssa.BlockExit) + hi := s.newValue1(ssa.OpInt64Hi, types.Types[types.TUINT32], idx) + cmp := s.newValue2(ssa.OpEq32, types.Types[types.TBOOL], hi, s.constInt32(types.Types[types.TUINT32], 0)) + if !idx.Type.IsSigned() { + switch kind { + case ssa.BoundsIndex: + kind = ssa.BoundsIndexU + case ssa.BoundsSliceAlen: + kind = ssa.BoundsSliceAlenU + case ssa.BoundsSliceAcap: + kind = ssa.BoundsSliceAcapU + case ssa.BoundsSliceB: + kind = ssa.BoundsSliceBU + case ssa.BoundsSlice3Alen: + kind = ssa.BoundsSlice3AlenU + case ssa.BoundsSlice3Acap: + kind = ssa.BoundsSlice3AcapU + case ssa.BoundsSlice3B: + kind = ssa.BoundsSlice3BU + case ssa.BoundsSlice3C: + kind = ssa.BoundsSlice3CU + } + } + b := s.endBlock() + b.Kind = ssa.BlockIf + b.SetControl(cmp) + b.Likely = ssa.BranchLikely + b.AddEdgeTo(bNext) + b.AddEdgeTo(bPanic) + + s.startBlock(bPanic) + mem := s.newValue4I(ssa.OpPanicExtend, types.TypeMem, int64(kind), hi, lo, len, s.mem()) + s.endBlock().SetControl(mem) + s.startBlock(bNext) + + return lo + } + + // Extend value to the required size + var op ssa.Op + if idx.Type.IsSigned() { + switch 10*size + s.config.PtrSize { + case 14: + op = ssa.OpSignExt8to32 + case 18: + op = ssa.OpSignExt8to64 + case 24: + op = ssa.OpSignExt16to32 + case 28: + op = ssa.OpSignExt16to64 + case 48: + op = ssa.OpSignExt32to64 + default: + s.Fatalf("bad signed index extension %s", idx.Type) + } + } else { + switch 10*size + s.config.PtrSize { + case 14: + op = ssa.OpZeroExt8to32 + case 18: + op = ssa.OpZeroExt8to64 + case 24: + op = ssa.OpZeroExt16to32 + case 28: + op = ssa.OpZeroExt16to64 + case 48: + op = ssa.OpZeroExt32to64 + default: + s.Fatalf("bad unsigned index extension %s", idx.Type) + } + } + return s.newValue1(op, types.Types[types.TINT], idx) +} + +// CheckLoweredPhi checks that regalloc and stackalloc correctly handled phi values. +// Called during ssaGenValue. +func CheckLoweredPhi(v *ssa.Value) { + if v.Op != ssa.OpPhi { + v.Fatalf("CheckLoweredPhi called with non-phi value: %v", v.LongString()) + } + if v.Type.IsMemory() { + return + } + f := v.Block.Func + loc := f.RegAlloc[v.ID] + for _, a := range v.Args { + if aloc := f.RegAlloc[a.ID]; aloc != loc { // TODO: .Equal() instead? + v.Fatalf("phi arg at different location than phi: %v @ %s, but arg %v @ %s\n%s\n", v, loc, a, aloc, v.Block.Func) + } + } +} + +// CheckLoweredGetClosurePtr checks that v is the first instruction in the function's entry block, +// except for incoming in-register arguments. +// The output of LoweredGetClosurePtr is generally hardwired to the correct register. +// That register contains the closure pointer on closure entry. +func CheckLoweredGetClosurePtr(v *ssa.Value) { + entry := v.Block.Func.Entry + if entry != v.Block { + base.Fatalf("in %s, badly placed LoweredGetClosurePtr: %v %v", v.Block.Func.Name, v.Block, v) + } + for _, w := range entry.Values { + if w == v { + break + } + switch w.Op { + case ssa.OpArgIntReg, ssa.OpArgFloatReg: + // okay + default: + base.Fatalf("in %s, badly placed LoweredGetClosurePtr: %v %v", v.Block.Func.Name, v.Block, v) + } + } +} + +// CheckArgReg ensures that v is in the function's entry block. +func CheckArgReg(v *ssa.Value) { + entry := v.Block.Func.Entry + if entry != v.Block { + base.Fatalf("in %s, badly placed ArgIReg or ArgFReg: %v %v", v.Block.Func.Name, v.Block, v) + } +} + +func AddrAuto(a *obj.Addr, v *ssa.Value) { + n, off := ssa.AutoVar(v) + a.Type = obj.TYPE_MEM + a.Sym = n.Linksym() + a.Reg = int16(Arch.REGSP) + a.Offset = n.FrameOffset() + off + if n.Class == ir.PPARAM || (n.Class == ir.PPARAMOUT && !n.IsOutputParamInRegisters()) { + a.Name = obj.NAME_PARAM + } else { + a.Name = obj.NAME_AUTO + } +} + +// Call returns a new CALL instruction for the SSA value v. +// It uses PrepareCall to prepare the call. +func (s *State) Call(v *ssa.Value) *obj.Prog { + pPosIsStmt := s.pp.Pos.IsStmt() // The statement-ness fo the call comes from ssaGenState + s.PrepareCall(v) + + p := s.Prog(obj.ACALL) + if pPosIsStmt == src.PosIsStmt { + p.Pos = v.Pos.WithIsStmt() + } else { + p.Pos = v.Pos.WithNotStmt() + } + if sym, ok := v.Aux.(*ssa.AuxCall); ok && sym.Fn != nil { + p.To.Type = obj.TYPE_MEM + p.To.Name = obj.NAME_EXTERN + p.To.Sym = sym.Fn + } else { + // TODO(mdempsky): Can these differences be eliminated? + switch Arch.LinkArch.Family { + case sys.AMD64, sys.I386, sys.PPC64, sys.RISCV64, sys.S390X, sys.Wasm: + p.To.Type = obj.TYPE_REG + case sys.ARM, sys.ARM64, sys.Loong64, sys.MIPS, sys.MIPS64: + p.To.Type = obj.TYPE_MEM + default: + base.Fatalf("unknown indirect call family") + } + p.To.Reg = v.Args[0].Reg() + } + return p +} + +// TailCall returns a new tail call instruction for the SSA value v. +// It is like Call, but for a tail call. +func (s *State) TailCall(v *ssa.Value) *obj.Prog { + p := s.Call(v) + p.As = obj.ARET + return p +} + +// PrepareCall prepares to emit a CALL instruction for v and does call-related bookkeeping. +// It must be called immediately before emitting the actual CALL instruction, +// since it emits PCDATA for the stack map at the call (calls are safe points). +func (s *State) PrepareCall(v *ssa.Value) { + idx := s.livenessMap.Get(v) + if !idx.StackMapValid() { + // See Liveness.hasStackMap. + if sym, ok := v.Aux.(*ssa.AuxCall); !ok || !(sym.Fn == ir.Syms.WBZero || sym.Fn == ir.Syms.WBMove) { + base.Fatalf("missing stack map index for %v", v.LongString()) + } + } + + call, ok := v.Aux.(*ssa.AuxCall) + + if ok { + // Record call graph information for nowritebarrierrec + // analysis. + if nowritebarrierrecCheck != nil { + nowritebarrierrecCheck.recordCall(s.pp.CurFunc, call.Fn, v.Pos) + } + } + + if s.maxarg < v.AuxInt { + s.maxarg = v.AuxInt + } +} + +// UseArgs records the fact that an instruction needs a certain amount of +// callee args space for its use. +func (s *State) UseArgs(n int64) { + if s.maxarg < n { + s.maxarg = n + } +} + +// fieldIdx finds the index of the field referred to by the ODOT node n. +func fieldIdx(n *ir.SelectorExpr) int { + t := n.X.Type() + if !t.IsStruct() { + panic("ODOT's LHS is not a struct") + } + + for i, f := range t.Fields().Slice() { + if f.Sym == n.Sel { + if f.Offset != n.Offset() { + panic("field offset doesn't match") + } + return i + } + } + panic(fmt.Sprintf("can't find field in expr %v\n", n)) + + // TODO: keep the result of this function somewhere in the ODOT Node + // so we don't have to recompute it each time we need it. +} + +// ssafn holds frontend information about a function that the backend is processing. +// It also exports a bunch of compiler services for the ssa backend. +type ssafn struct { + curfn *ir.Func + strings map[string]*obj.LSym // map from constant string to data symbols + stksize int64 // stack size for current frame + stkptrsize int64 // prefix of stack containing pointers + + // alignment for current frame. + // NOTE: when stkalign > PtrSize, currently this only ensures the offsets of + // objects in the stack frame are aligned. The stack pointer is still aligned + // only PtrSize. + stkalign int64 + + log bool // print ssa debug to the stdout +} + +// StringData returns a symbol which +// is the data component of a global string constant containing s. +func (e *ssafn) StringData(s string) *obj.LSym { + if aux, ok := e.strings[s]; ok { + return aux + } + if e.strings == nil { + e.strings = make(map[string]*obj.LSym) + } + data := staticdata.StringSym(e.curfn.Pos(), s) + e.strings[s] = data + return data +} + +func (e *ssafn) Auto(pos src.XPos, t *types.Type) *ir.Name { + return typecheck.TempAt(pos, e.curfn, t) // Note: adds new auto to e.curfn.Func.Dcl list +} + +// SplitSlot returns a slot representing the data of parent starting at offset. +func (e *ssafn) SplitSlot(parent *ssa.LocalSlot, suffix string, offset int64, t *types.Type) ssa.LocalSlot { + node := parent.N + + if node.Class != ir.PAUTO || node.Addrtaken() { + // addressed things and non-autos retain their parents (i.e., cannot truly be split) + return ssa.LocalSlot{N: node, Type: t, Off: parent.Off + offset} + } + + s := &types.Sym{Name: node.Sym().Name + suffix, Pkg: types.LocalPkg} + n := ir.NewNameAt(parent.N.Pos(), s) + s.Def = n + ir.AsNode(s.Def).Name().SetUsed(true) + n.SetType(t) + n.Class = ir.PAUTO + n.SetEsc(ir.EscNever) + n.Curfn = e.curfn + e.curfn.Dcl = append(e.curfn.Dcl, n) + types.CalcSize(t) + return ssa.LocalSlot{N: n, Type: t, Off: 0, SplitOf: parent, SplitOffset: offset} +} + +func (e *ssafn) CanSSA(t *types.Type) bool { + return TypeOK(t) +} + +// Logf logs a message from the compiler. +func (e *ssafn) Logf(msg string, args ...interface{}) { + if e.log { + fmt.Printf(msg, args...) + } +} + +func (e *ssafn) Log() bool { + return e.log +} + +// Fatalf reports a compiler error and exits. +func (e *ssafn) Fatalf(pos src.XPos, msg string, args ...interface{}) { + base.Pos = pos + nargs := append([]interface{}{ir.FuncName(e.curfn)}, args...) + base.Fatalf("'%s': "+msg, nargs...) +} + +// Warnl reports a "warning", which is usually flag-triggered +// logging output for the benefit of tests. +func (e *ssafn) Warnl(pos src.XPos, fmt_ string, args ...interface{}) { + base.WarnfAt(pos, fmt_, args...) +} + +func (e *ssafn) Debug_checknil() bool { + return base.Debug.Nil != 0 +} + +func (e *ssafn) UseWriteBarrier() bool { + return base.Flag.WB +} + +func (e *ssafn) Syslook(name string) *obj.LSym { + switch name { + case "goschedguarded": + return ir.Syms.Goschedguarded + case "writeBarrier": + return ir.Syms.WriteBarrier + case "wbZero": + return ir.Syms.WBZero + case "wbMove": + return ir.Syms.WBMove + case "cgoCheckMemmove": + return ir.Syms.CgoCheckMemmove + case "cgoCheckPtrWrite": + return ir.Syms.CgoCheckPtrWrite + } + e.Fatalf(src.NoXPos, "unknown Syslook func %v", name) + return nil +} + +func (e *ssafn) MyImportPath() string { + return base.Ctxt.Pkgpath +} + +func (e *ssafn) Func() *ir.Func { + return e.curfn +} + +func clobberBase(n ir.Node) ir.Node { + if n.Op() == ir.ODOT { + n := n.(*ir.SelectorExpr) + if n.X.Type().NumFields() == 1 { + return clobberBase(n.X) + } + } + if n.Op() == ir.OINDEX { + n := n.(*ir.IndexExpr) + if n.X.Type().IsArray() && n.X.Type().NumElem() == 1 { + return clobberBase(n.X) + } + } + return n +} + +// callTargetLSym returns the correct LSym to call 'callee' using its ABI. +func callTargetLSym(callee *ir.Name) *obj.LSym { + if callee.Func == nil { + // TODO(austin): This happens in case of interface method I.M from imported package. + // It's ABIInternal, and would be better if callee.Func was never nil and we didn't + // need this case. + return callee.Linksym() + } + + return callee.LinksymABI(callee.Func.ABI) +} + +func min8(a, b int8) int8 { + if a < b { + return a + } + return b +} + +func max8(a, b int8) int8 { + if a > b { + return a + } + return b +} + +// deferstruct makes a runtime._defer structure. +func deferstruct() *types.Type { + makefield := func(name string, typ *types.Type) *types.Field { + // Unlike the global makefield function, this one needs to set Pkg + // because these types might be compared (in SSA CSE sorting). + // TODO: unify this makefield and the global one above. + sym := &types.Sym{Name: name, Pkg: types.LocalPkg} + return types.NewField(src.NoXPos, sym, typ) + } + // These fields must match the ones in runtime/runtime2.go:_defer and + // (*state).call above. + fields := []*types.Field{ + makefield("started", types.Types[types.TBOOL]), + makefield("heap", types.Types[types.TBOOL]), + makefield("openDefer", types.Types[types.TBOOL]), + makefield("sp", types.Types[types.TUINTPTR]), + makefield("pc", types.Types[types.TUINTPTR]), + // Note: the types here don't really matter. Defer structures + // are always scanned explicitly during stack copying and GC, + // so we make them uintptr type even though they are real pointers. + makefield("fn", types.Types[types.TUINTPTR]), + makefield("_panic", types.Types[types.TUINTPTR]), + makefield("link", types.Types[types.TUINTPTR]), + makefield("fd", types.Types[types.TUINTPTR]), + makefield("varp", types.Types[types.TUINTPTR]), + makefield("framepc", types.Types[types.TUINTPTR]), + } + + // build struct holding the above fields + s := types.NewStruct(fields) + s.SetNoalg(true) + types.CalcStructSize(s) + return s +} + +// SpillSlotAddr uses LocalSlot information to initialize an obj.Addr +// The resulting addr is used in a non-standard context -- in the prologue +// of a function, before the frame has been constructed, so the standard +// addressing for the parameters will be wrong. +func SpillSlotAddr(spill ssa.Spill, baseReg int16, extraOffset int64) obj.Addr { + return obj.Addr{ + Name: obj.NAME_NONE, + Type: obj.TYPE_MEM, + Reg: baseReg, + Offset: spill.Offset + extraOffset, + } +} + +var ( + BoundsCheckFunc [ssa.BoundsKindCount]*obj.LSym + ExtendCheckFunc [ssa.BoundsKindCount]*obj.LSym +) |