diff --git a/src/cmd/compile/internal/noder/codes.go b/src/cmd/compile/internal/noder/codes.go new file mode 100644 index 0000000000..4a6a4e8307 --- /dev/null +++ b/src/cmd/compile/internal/noder/codes.go @@ -0,0 +1,126 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +type code interface { + marker() syncMarker + value() int +} + +type codeVal int + +func (c codeVal) marker() syncMarker { return syncVal } +func (c codeVal) value() int { return int(c) } + +const ( + valBool codeVal = iota + valString + valInt64 + valBigInt + valBigRat + valBigFloat +) + +type codeType int + +func (c codeType) marker() syncMarker { return syncType } +func (c codeType) value() int { return int(c) } + +const ( + typeBasic codeType = iota + typeNamed + typePointer + typeSlice + typeArray + typeChan + typeMap + typeSignature + typeStruct + typeInterface + typeUnion + typeTypeParam +) + +type codeObj int + +func (c codeObj) marker() syncMarker { return syncCodeObj } +func (c codeObj) value() int { return int(c) } + +const ( + objAlias codeObj = iota + objConst + objType + objFunc + objVar + objStub +) + +type codeStmt int + +func (c codeStmt) marker() syncMarker { return syncStmt1 } +func (c codeStmt) value() int { return int(c) } + +const ( + stmtEnd codeStmt = iota + stmtLabel + stmtBlock + stmtExpr + stmtSend + stmtAssign + stmtAssignOp + stmtIncDec + stmtBranch + stmtCall + stmtReturn + stmtIf + stmtFor + stmtSwitch + stmtSelect + + // TODO(mdempsky): Remove after we don't care about toolstash -cmp. + stmtTypeDeclHack +) + +type codeExpr int + +func (c codeExpr) marker() syncMarker { return syncExpr } +func (c codeExpr) value() int { return int(c) } + +// TODO(mdempsky): Split expr into addr, for lvalues. +const ( + exprNone codeExpr = iota + exprConst + exprType // type expression + exprLocal // local variable + exprName // global variable or function + exprBlank + exprCompLit + exprFuncLit + exprSelector + exprIndex + exprSlice + exprAssert + exprUnaryOp + exprBinaryOp + exprCall + + // TODO(mdempsky): Handle in switchStmt directly instead. + exprTypeSwitchGuard +) + +type codeDecl int + +func (c codeDecl) marker() syncMarker { return syncDecl } +func (c codeDecl) value() int { return int(c) } + +const ( + declEnd codeDecl = iota + declFunc + declMethod + declVar + declOther +) diff --git a/src/cmd/compile/internal/noder/decoder.go b/src/cmd/compile/internal/noder/decoder.go new file mode 100644 index 0000000000..023388875c --- /dev/null +++ b/src/cmd/compile/internal/noder/decoder.go @@ -0,0 +1,243 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "encoding/binary" + "fmt" + "go/constant" + "go/token" + "math/big" + "os" + "strings" + + "cmd/compile/internal/base" +) + +type pkgDecoder struct { + pkgPath string + + elemEndsEnds [numRelocs]uint32 + elemEnds []uint32 + elemData string +} + +func newPkgDecoder(pkgPath, input string) pkgDecoder { + pr := pkgDecoder{ + pkgPath: pkgPath, + } + + // TODO(mdempsky): Implement direct indexing of input string to + // avoid copying the position information. + + r := strings.NewReader(input) + + assert(binary.Read(r, binary.LittleEndian, pr.elemEndsEnds[:]) == nil) + + pr.elemEnds = make([]uint32, pr.elemEndsEnds[len(pr.elemEndsEnds)-1]) + assert(binary.Read(r, binary.LittleEndian, pr.elemEnds[:]) == nil) + + pos, err := r.Seek(0, os.SEEK_CUR) + assert(err == nil) + + pr.elemData = input[pos:] + assert(len(pr.elemData) == int(pr.elemEnds[len(pr.elemEnds)-1])) + + return pr +} + +func (pr *pkgDecoder) numElems(k reloc) int { + count := int(pr.elemEndsEnds[k]) + if k > 0 { + count -= int(pr.elemEndsEnds[k-1]) + } + return count +} + +func (pr *pkgDecoder) totalElems() int { + return len(pr.elemEnds) +} + +func (pr *pkgDecoder) absIdx(k reloc, idx int) int { + absIdx := idx + if k > 0 { + absIdx += int(pr.elemEndsEnds[k-1]) + } + if absIdx >= int(pr.elemEndsEnds[k]) { + base.Fatalf("%v:%v is out of bounds; %v", k, idx, pr.elemEndsEnds) + } + return absIdx +} + +func (pr *pkgDecoder) dataIdx(k reloc, idx int) string { + absIdx := pr.absIdx(k, idx) + + var start uint32 + if absIdx > 0 { + start = pr.elemEnds[absIdx-1] + } + end := pr.elemEnds[absIdx] + + return pr.elemData[start:end] +} + +func (pr *pkgDecoder) stringIdx(idx int) string { + return pr.dataIdx(relocString, idx) +} + +func (pr *pkgDecoder) newDecoder(k reloc, idx int, marker syncMarker) decoder { + r := pr.newDecoderRaw(k, idx) + r.sync(marker) + return r +} + +func (pr *pkgDecoder) newDecoderRaw(k reloc, idx int) decoder { + r := decoder{ + common: pr, + k: k, + idx: idx, + } + + // TODO(mdempsky) r.data.Reset(...) after #44505 is resolved. + r.data = *strings.NewReader(pr.dataIdx(k, idx)) + + r.sync(syncRelocs) + r.relocs = make([]relocEnt, r.len()) + for i := range r.relocs { + r.sync(syncReloc) + r.relocs[i] = relocEnt{reloc(r.len()), r.len()} + } + + return r +} + +type decoder struct { + common *pkgDecoder + + relocs []relocEnt + data strings.Reader + + k reloc + idx int +} + +func (r *decoder) checkErr(err error) { + if err != nil { + base.Fatalf("unexpected error: %v", err) + } +} + +func (r *decoder) sync(m syncMarker) { + if debug { + pos, err0 := r.data.Seek(0, os.SEEK_CUR) + x, err := r.data.ReadByte() + r.checkErr(err) + if x != byte(m) { + // TODO(mdempsky): Revisit this error message, and make it more + // useful (e.g., include r.p.pkgPath). + base.Fatalf("data sync error: found %v at %v (%v) in (%v:%v), but expected %v", syncMarker(x), pos, err0, r.k, r.idx, m) + } + } +} + +func (r *decoder) bool() bool { + r.sync(syncBool) + x, err := r.data.ReadByte() + r.checkErr(err) + assert(x < 2) + return x != 0 +} + +func (r *decoder) int64() int64 { + r.sync(syncInt64) + x, err := binary.ReadVarint(&r.data) + r.checkErr(err) + return x +} + +func (r *decoder) uint64() uint64 { + r.sync(syncUint64) + x, err := binary.ReadUvarint(&r.data) + r.checkErr(err) + return x +} + +func (r *decoder) len() int { x := r.uint64(); v := int(x); assert(uint64(v) == x); return v } +func (r *decoder) int() int { x := r.int64(); v := int(x); assert(int64(v) == x); return v } +func (r *decoder) uint() uint { x := r.uint64(); v := uint(x); assert(uint64(v) == x); return v } + +func (r *decoder) code(mark syncMarker) int { + r.sync(mark) + return r.len() +} + +func (r *decoder) reloc(k reloc) int { + r.sync(syncUseReloc) + idx := r.len() + + e := r.relocs[idx] + assert(e.kind == k) + return e.idx +} + +func (r *decoder) string() string { + r.sync(syncString) + return r.common.stringIdx(r.reloc(relocString)) +} + +func (r *decoder) strings() []string { + res := make([]string, r.len()) + for i := range res { + res[i] = r.string() + } + return res +} + +func (r *decoder) rawValue() constant.Value { + isComplex := r.bool() + val := r.scalar() + if isComplex { + val = constant.BinaryOp(val, token.ADD, constant.MakeImag(r.scalar())) + } + return val +} + +func (r *decoder) scalar() constant.Value { + switch tag := codeVal(r.code(syncVal)); tag { + default: + panic(fmt.Sprintf("unexpected scalar tag: %v", tag)) + + case valBool: + return constant.MakeBool(r.bool()) + case valString: + return constant.MakeString(r.string()) + case valInt64: + return constant.MakeInt64(r.int64()) + case valBigInt: + return constant.Make(r.bigInt()) + case valBigRat: + num := r.bigInt() + denom := r.bigInt() + return constant.Make(new(big.Rat).SetFrac(num, denom)) + case valBigFloat: + return constant.Make(r.bigFloat()) + } +} + +func (r *decoder) bigInt() *big.Int { + v := new(big.Int).SetBytes([]byte(r.string())) + if r.bool() { + v.Neg(v) + } + return v +} + +func (r *decoder) bigFloat() *big.Float { + v := new(big.Float).SetPrec(512) + assert(v.UnmarshalText([]byte(r.string())) == nil) + return v +} diff --git a/src/cmd/compile/internal/noder/encoder.go b/src/cmd/compile/internal/noder/encoder.go new file mode 100644 index 0000000000..dc288dc29f --- /dev/null +++ b/src/cmd/compile/internal/noder/encoder.go @@ -0,0 +1,245 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "bytes" + "encoding/binary" + "fmt" + "go/constant" + "io" + "math/big" + + "cmd/compile/internal/base" +) + +type pkgEncoder struct { + elems [numRelocs][]string + + stringsIdx map[string]int +} + +func newPkgEncoder() pkgEncoder { + return pkgEncoder{ + stringsIdx: make(map[string]int), + } +} + +func (pw *pkgEncoder) dump(out io.Writer) { + writeUint32 := func(x uint32) { + assert(binary.Write(out, binary.LittleEndian, x) == nil) + } + + var sum uint32 + for _, elems := range &pw.elems { + sum += uint32(len(elems)) + writeUint32(sum) + } + + sum = 0 + for _, elems := range &pw.elems { + for _, elem := range elems { + sum += uint32(len(elem)) + writeUint32(sum) + } + } + + for _, elems := range &pw.elems { + for _, elem := range elems { + _, err := io.WriteString(out, elem) + assert(err == nil) + } + } +} + +func (pw *pkgEncoder) stringIdx(s string) int { + if idx, ok := pw.stringsIdx[s]; ok { + assert(pw.elems[relocString][idx] == s) + return idx + } + + idx := len(pw.elems[relocString]) + pw.elems[relocString] = append(pw.elems[relocString], s) + pw.stringsIdx[s] = idx + return idx +} + +func (pw *pkgEncoder) newEncoder(k reloc, marker syncMarker) encoder { + e := pw.newEncoderRaw(k) + e.sync(marker) + return e +} + +func (pw *pkgEncoder) newEncoderRaw(k reloc) encoder { + idx := len(pw.elems[k]) + pw.elems[k] = append(pw.elems[k], "") // placeholder + + return encoder{ + p: pw, + k: k, + idx: idx, + } +} + +// Encoders + +type encoder struct { + p *pkgEncoder + + relocs []relocEnt + data bytes.Buffer + + k reloc + idx int +} + +func (w *encoder) flush() int { + var sb bytes.Buffer // TODO(mdempsky): strings.Builder after #44505 is resolved + + // Backup the data so we write the relocations at the front. + var tmp bytes.Buffer + io.Copy(&tmp, &w.data) + + // TODO(mdempsky): Consider writing these out separately so they're + // easier to strip, along with function bodies, so that we can prune + // down to just the data that's relevant to go/types. + w.sync(syncRelocs) + w.len(len(w.relocs)) + for _, rent := range w.relocs { + w.sync(syncReloc) + w.len(int(rent.kind)) + w.len(rent.idx) + } + + io.Copy(&sb, &w.data) + io.Copy(&sb, &tmp) + w.p.elems[w.k][w.idx] = sb.String() + + return w.idx +} + +func (w *encoder) checkErr(err error) { + if err != nil { + base.Fatalf("unexpected error: %v", err) + } +} + +func (w *encoder) sync(m syncMarker) { + if debug { + err := w.data.WriteByte(byte(m)) + w.checkErr(err) + } +} + +func (w *encoder) bool(b bool) bool { + w.sync(syncBool) + var x byte + if b { + x = 1 + } + err := w.data.WriteByte(x) + w.checkErr(err) + return b +} + +func (w *encoder) int64(x int64) { + w.sync(syncInt64) + var buf [binary.MaxVarintLen64]byte + n := binary.PutVarint(buf[:], x) + _, err := w.data.Write(buf[:n]) + w.checkErr(err) +} + +func (w *encoder) uint64(x uint64) { + w.sync(syncUint64) + var buf [binary.MaxVarintLen64]byte + n := binary.PutUvarint(buf[:], x) + _, err := w.data.Write(buf[:n]) + w.checkErr(err) +} + +func (w *encoder) len(x int) { assert(x >= 0); w.uint64(uint64(x)) } +func (w *encoder) int(x int) { w.int64(int64(x)) } +func (w *encoder) uint(x uint) { w.uint64(uint64(x)) } + +func (w *encoder) reloc(r reloc, idx int) { + w.sync(syncUseReloc) + + // TODO(mdempsky): Use map for lookup. + for i, rent := range w.relocs { + if rent.kind == r && rent.idx == idx { + w.len(i) + return + } + } + + w.len(len(w.relocs)) + w.relocs = append(w.relocs, relocEnt{r, idx}) +} + +func (w *encoder) code(c code) { + w.sync(c.marker()) + w.len(c.value()) +} + +func (w *encoder) string(s string) { + w.sync(syncString) + w.reloc(relocString, w.p.stringIdx(s)) +} + +func (w *encoder) strings(ss []string) { + w.len(len(ss)) + for _, s := range ss { + w.string(s) + } +} + +func (w *encoder) rawValue(val constant.Value) { + if w.bool(val.Kind() == constant.Complex) { + w.scalar(constant.Real(val)) + w.scalar(constant.Imag(val)) + } else { + w.scalar(val) + } +} + +func (w *encoder) scalar(val constant.Value) { + switch v := constant.Val(val).(type) { + default: + panic(fmt.Sprintf("unhandled %v (%v)", val, val.Kind())) + case bool: + w.code(valBool) + w.bool(v) + case string: + w.code(valString) + w.string(v) + case int64: + w.code(valInt64) + w.int64(v) + case *big.Int: + w.code(valBigInt) + w.bigInt(v) + case *big.Rat: + w.code(valBigRat) + w.bigInt(v.Num()) + w.bigInt(v.Denom()) + case *big.Float: + w.code(valBigFloat) + w.bigFloat(v) + } +} + +func (w *encoder) bigInt(v *big.Int) { + b := v.Bytes() + w.string(string(b)) // TODO: More efficient encoding. + w.bool(v.Sign() < 0) +} + +func (w *encoder) bigFloat(v *big.Float) { + b := v.Append(nil, 'p', -1) + w.string(string(b)) // TODO: More efficient encoding. +} diff --git a/src/cmd/compile/internal/noder/linker.go b/src/cmd/compile/internal/noder/linker.go new file mode 100644 index 0000000000..324902d246 --- /dev/null +++ b/src/cmd/compile/internal/noder/linker.go @@ -0,0 +1,296 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "io" + + "cmd/compile/internal/base" + "cmd/compile/internal/ir" + "cmd/compile/internal/reflectdata" + "cmd/compile/internal/types" + "cmd/internal/goobj" + "cmd/internal/obj" +) + +// This file implements the unified IR linker, which combines the +// local package's stub data with imported package data to produce a +// complete export data file. It also rewrites the compiler's +// extension data sections based on the results of compilation (e.g., +// the function inlining cost and linker symbol index assignments). +// +// TODO(mdempsky): Using the name "linker" here is confusing, because +// readers are likely to mistake references to it for cmd/link. But +// there's a shortage of good names for "something that combines +// multiple parts into a cohesive whole"... e.g., "assembler" and +// "compiler" are also already taken. + +type linker struct { + pw pkgEncoder + + pkgs map[string]int + decls map[*types.Sym]int +} + +func (l *linker) relocAll(pr *pkgReader, relocs []relocEnt) []relocEnt { + res := make([]relocEnt, len(relocs)) + for i, rent := range relocs { + rent.idx = l.relocIdx(pr, rent.kind, rent.idx) + res[i] = rent + } + return res +} + +func (l *linker) relocIdx(pr *pkgReader, k reloc, idx int) int { + assert(pr != nil) + + absIdx := pr.absIdx(k, idx) + + if newidx := pr.newindex[absIdx]; newidx != 0 { + return ^newidx + } + + var newidx int + switch k { + case relocString: + newidx = l.relocString(pr, idx) + case relocPkg: + newidx = l.relocPkg(pr, idx) + case relocObj: + newidx = l.relocObj(pr, idx) + + default: + // Generic relocations. + // + // TODO(mdempsky): Deduplicate more sections? In fact, I think + // every section could be deduplicated. This would also be easier + // if we do external relocations. + + w := l.pw.newEncoderRaw(k) + l.relocCommon(pr, &w, k, idx) + newidx = w.idx + } + + pr.newindex[absIdx] = ^newidx + + return newidx +} + +func (l *linker) relocString(pr *pkgReader, idx int) int { + return l.pw.stringIdx(pr.stringIdx(idx)) +} + +func (l *linker) relocPkg(pr *pkgReader, idx int) int { + path := pr.peekPkgPath(idx) + + if newidx, ok := l.pkgs[path]; ok { + return newidx + } + + r := pr.newDecoder(relocPkg, idx, syncPkgDef) + w := l.pw.newEncoder(relocPkg, syncPkgDef) + l.pkgs[path] = w.idx + + // TODO(mdempsky): We end up leaving an empty string reference here + // from when the package was originally written as "". Probably not + // a big deal, but a little annoying. Maybe relocating + // cross-references in place is the way to go after all. + w.relocs = l.relocAll(pr, r.relocs) + + _ = r.string() // original path + w.string(path) + + io.Copy(&w.data, &r.data) + + return w.flush() +} + +func (l *linker) relocObj(pr *pkgReader, idx int) int { + path, name, tag, _ := pr.peekObj(idx) + sym := types.NewPkg(path, "").Lookup(name) + + if newidx, ok := l.decls[sym]; ok { + return newidx + } + + if tag == objStub && path != "builtin" && path != "unsafe" { + pri, ok := objReader[sym] + if !ok { + base.Fatalf("missing reader for %q.%v", path, name) + } + assert(ok) + + pr = pri.pr + idx = pri.idx + + path2, name2, tag2, _ := pr.peekObj(idx) + sym2 := types.NewPkg(path2, "").Lookup(name2) + assert(sym == sym2) + assert(tag2 != objStub) + } + + w := l.pw.newEncoderRaw(relocObj) + bside := l.pw.newEncoderRaw(relocObjExt) + assert(bside.idx == w.idx) + l.decls[sym] = w.idx + + l.relocCommon(pr, &w, relocObj, idx) + + var obj *ir.Name + if path == "" { + var ok bool + obj, ok = sym.Def.(*ir.Name) + + // Generic types and functions won't have definitions. + // For now, just generically copy their extension data. + if !ok && base.Flag.G == 0 { + base.Fatalf("missing definition for %v", sym) + } + } + + if obj != nil { + bside.sync(syncObject1) + switch tag { + case objFunc: + l.relocFuncExt(&bside, obj) + case objType: + l.relocTypeExt(&bside, obj) + case objVar: + l.relocVarExt(&bside, obj) + } + bside.flush() + } else { + l.relocCommon(pr, &bside, relocObjExt, idx) + } + + return w.idx +} + +func (l *linker) relocCommon(pr *pkgReader, w *encoder, k reloc, idx int) { + r := pr.newDecoderRaw(k, idx) + w.relocs = l.relocAll(pr, r.relocs) + io.Copy(&w.data, &r.data) + w.flush() +} + +func (l *linker) pragmaFlag(w *encoder, pragma ir.PragmaFlag) { + w.sync(syncPragma) + w.int(int(pragma)) +} + +func (l *linker) relocFuncExt(w *encoder, name *ir.Name) { + w.sync(syncFuncExt) + + l.pragmaFlag(w, name.Func.Pragma) + l.linkname(w, name) + + // Relocated extension data. + w.bool(true) + + // Record definition ABI so cross-ABI calls can be direct. + // This is important for the performance of calling some + // common functions implemented in assembly (e.g., bytealg). + w.uint64(uint64(name.Func.ABI)) + + // Escape analysis. + for _, fs := range &types.RecvsParams { + for _, f := range fs(name.Type()).FieldSlice() { + w.string(f.Note) + } + } + + if inl := name.Func.Inl; w.bool(inl != nil) { + w.len(int(inl.Cost)) + w.bool(inl.CanDelayResults) + + pri, ok := bodyReader[name.Func] + assert(ok) + w.sync(syncAddBody) + w.reloc(relocBody, l.relocIdx(pri.pr, relocBody, pri.idx)) + } + + w.sync(syncEOF) +} + +func (l *linker) relocTypeExt(w *encoder, name *ir.Name) { + w.sync(syncTypeExt) + + typ := name.Type() + + l.pragmaFlag(w, name.Pragma()) + + // For type T, export the index of type descriptor symbols of T and *T. + l.lsymIdx(w, "", reflectdata.TypeLinksym(typ)) + l.lsymIdx(w, "", reflectdata.TypeLinksym(typ.PtrTo())) + + if typ.Kind() != types.TINTER { + for _, method := range typ.Methods().Slice() { + l.relocFuncExt(w, method.Nname.(*ir.Name)) + } + } +} + +func (l *linker) relocVarExt(w *encoder, name *ir.Name) { + w.sync(syncVarExt) + l.linkname(w, name) +} + +func (l *linker) linkname(w *encoder, name *ir.Name) { + w.sync(syncLinkname) + + linkname := name.Sym().Linkname + if !l.lsymIdx(w, linkname, name.Linksym()) { + w.string(linkname) + } +} + +func (l *linker) lsymIdx(w *encoder, linkname string, lsym *obj.LSym) bool { + if lsym.PkgIdx > goobj.PkgIdxSelf || (lsym.PkgIdx == goobj.PkgIdxInvalid && !lsym.Indexed()) || linkname != "" { + w.int64(-1) + return false + } + + // For a defined symbol, export its index. + // For re-exporting an imported symbol, pass its index through. + w.int64(int64(lsym.SymIdx)) + return true +} + +// @@@ Helpers + +// TODO(mdempsky): These should probably be removed. I think they're a +// smell that the export data format is not yet quite right. + +func (pr *pkgDecoder) peekPkgPath(idx int) string { + r := pr.newDecoder(relocPkg, idx, syncPkgDef) + path := r.string() + if path == "" { + path = pr.pkgPath + } + return path +} + +func (pr *pkgDecoder) peekObj(idx int) (string, string, codeObj, []int) { + r := pr.newDecoder(relocObj, idx, syncObject1) + r.sync(syncSym) + r.sync(syncPkg) + path := pr.peekPkgPath(r.reloc(relocPkg)) + name := r.string() + assert(name != "") + + r.sync(syncTypeParamBounds) + r.len() // implicits + bounds := make([]int, r.len()) + for i := range bounds { + r.sync(syncType) + bounds[i] = r.reloc(relocType) + } + + tag := codeObj(r.code(syncCodeObj)) + + return path, name, tag, bounds +} diff --git a/src/cmd/compile/internal/noder/quirks.go b/src/cmd/compile/internal/noder/quirks.go new file mode 100644 index 0000000000..9f33fc576d --- /dev/null +++ b/src/cmd/compile/internal/noder/quirks.go @@ -0,0 +1,453 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "fmt" + + "cmd/compile/internal/base" + "cmd/compile/internal/ir" + "cmd/compile/internal/syntax" + "cmd/compile/internal/types2" + "cmd/internal/src" +) + +// This file defines helper functions useful for satisfying toolstash +// -cmp when compared against the legacy frontend behavior, but can be +// removed after that's no longer a concern. + +// quirksMode controls whether behavior specific to satsifying +// toolstash -cmp is used. +func quirksMode() bool { + // Currently, unified IR doesn't try to be compatible with + // -d=inlfuncswithclosures=1, so we overload this as a flag for + // enabling quirks mode. + return base.Debug.InlFuncsWithClosures == 0 +} + +// posBasesOf returns all of the position bases in the source files, +// as seen in a straightforward traversal. +// +// This is necessary to ensure position bases (and thus file names) +// get registered in the same order as noder would visit them. +func posBasesOf(noders []*noder) []*syntax.PosBase { + seen := make(map[*syntax.PosBase]bool) + var bases []*syntax.PosBase + + for _, p := range noders { + syntax.Walk(p.file, func(n syntax.Node) bool { + if b := n.Pos().Base(); !seen[b] { + bases = append(bases, b) + seen[b] = true + } + return false + }) + } + + return bases +} + +// importedObjsOf returns the imported objects (i.e., referenced +// objects not declared by curpkg) from the parsed source files, in +// the order that typecheck used to load their definitions. +// +// This is needed because loading the definitions for imported objects +// can also add file names. +func importedObjsOf(curpkg *types2.Package, info *types2.Info, noders []*noder) []types2.Object { + // This code is complex because it matches the precise order that + // typecheck recursively and repeatedly traverses the IR. It's meant + // to be thrown away eventually anyway. + + seen := make(map[types2.Object]bool) + var objs []types2.Object + + var phase int + + decls := make(map[types2.Object]syntax.Decl) + assoc := func(decl syntax.Decl, names ...*syntax.Name) { + for _, name := range names { + obj, ok := info.Defs[name] + assert(ok) + decls[obj] = decl + } + } + + for _, p := range noders { + syntax.Walk(p.file, func(n syntax.Node) bool { + switch n := n.(type) { + case *syntax.ConstDecl: + assoc(n, n.NameList...) + case *syntax.FuncDecl: + assoc(n, n.Name) + case *syntax.TypeDecl: + assoc(n, n.Name) + case *syntax.VarDecl: + assoc(n, n.NameList...) + case *syntax.BlockStmt: + return true + } + return false + }) + } + + var visited map[syntax.Decl]bool + + var resolveDecl func(n syntax.Decl) + var resolveNode func(n syntax.Node, top bool) + + resolveDecl = func(n syntax.Decl) { + if visited[n] { + return + } + visited[n] = true + + switch n := n.(type) { + case *syntax.ConstDecl: + resolveNode(n.Type, true) + resolveNode(n.Values, true) + + case *syntax.FuncDecl: + if n.Recv != nil { + resolveNode(n.Recv, true) + } + resolveNode(n.Type, true) + + case *syntax.TypeDecl: + resolveNode(n.Type, true) + + case *syntax.VarDecl: + if n.Type != nil { + resolveNode(n.Type, true) + } else { + resolveNode(n.Values, true) + } + } + } + + resolveObj := func(pos syntax.Pos, obj types2.Object) { + switch obj.Pkg() { + case nil: + // builtin; nothing to do + + case curpkg: + if decl, ok := decls[obj]; ok { + resolveDecl(decl) + } + + default: + if obj.Parent() == obj.Pkg().Scope() && !seen[obj] { + seen[obj] = true + objs = append(objs, obj) + } + } + } + + checkdefat := func(pos syntax.Pos, n *syntax.Name) { + if n.Value == "_" { + return + } + obj, ok := info.Uses[n] + if !ok { + obj, ok = info.Defs[n] + if !ok { + return + } + } + if obj == nil { + return + } + resolveObj(pos, obj) + } + checkdef := func(n *syntax.Name) { checkdefat(n.Pos(), n) } + + var later []syntax.Node + + resolveNode = func(n syntax.Node, top bool) { + if n == nil { + return + } + syntax.Walk(n, func(n syntax.Node) bool { + switch n := n.(type) { + case *syntax.Name: + checkdef(n) + + case *syntax.SelectorExpr: + if name, ok := n.X.(*syntax.Name); ok { + if _, isPkg := info.Uses[name].(*types2.PkgName); isPkg { + checkdefat(n.X.Pos(), n.Sel) + return true + } + } + + case *syntax.AssignStmt: + resolveNode(n.Rhs, top) + resolveNode(n.Lhs, top) + return true + + case *syntax.VarDecl: + resolveNode(n.Values, top) + + case *syntax.FuncLit: + if top { + resolveNode(n.Type, top) + later = append(later, n.Body) + return true + } + + case *syntax.BlockStmt: + if phase >= 3 { + for _, stmt := range n.List { + resolveNode(stmt, false) + } + } + return true + } + + return false + }) + } + + for phase = 1; phase <= 5; phase++ { + visited = map[syntax.Decl]bool{} + + for _, p := range noders { + for _, decl := range p.file.DeclList { + switch decl := decl.(type) { + case *syntax.ConstDecl: + resolveDecl(decl) + + case *syntax.FuncDecl: + resolveDecl(decl) + if phase >= 3 && decl.Body != nil { + resolveNode(decl.Body, true) + } + + case *syntax.TypeDecl: + if !decl.Alias || phase >= 2 { + resolveDecl(decl) + } + + case *syntax.VarDecl: + if phase >= 2 { + resolveNode(decl.Values, true) + resolveDecl(decl) + } + } + } + + if phase >= 5 { + syntax.Walk(p.file, func(n syntax.Node) bool { + if name, ok := n.(*syntax.Name); ok { + if obj, ok := info.Uses[name]; ok { + resolveObj(name.Pos(), obj) + } + } + return false + }) + } + } + + for i := 0; i < len(later); i++ { + resolveNode(later[i], true) + } + later = nil + } + + return objs +} + +// typeExprEndPos returns the position that noder would leave base.Pos +// after parsing the given type expression. +func typeExprEndPos(expr0 syntax.Expr) syntax.Pos { + for { + switch expr := expr0.(type) { + case *syntax.Name: + return expr.Pos() + case *syntax.SelectorExpr: + return expr.X.Pos() + + case *syntax.ParenExpr: + expr0 = expr.X + + case *syntax.Operation: + assert(expr.Op == syntax.Mul) + assert(expr.Y == nil) + expr0 = expr.X + + case *syntax.ArrayType: + expr0 = expr.Elem + case *syntax.ChanType: + expr0 = expr.Elem + case *syntax.DotsType: + expr0 = expr.Elem + case *syntax.MapType: + expr0 = expr.Value + case *syntax.SliceType: + expr0 = expr.Elem + + case *syntax.StructType: + return expr.Pos() + + case *syntax.InterfaceType: + expr0 = lastFieldType(expr.MethodList) + if expr0 == nil { + return expr.Pos() + } + + case *syntax.FuncType: + expr0 = lastFieldType(expr.ResultList) + if expr0 == nil { + expr0 = lastFieldType(expr.ParamList) + if expr0 == nil { + return expr.Pos() + } + } + + case *syntax.IndexExpr: // explicit type instantiation + targs := unpackListExpr(expr.Index) + expr0 = targs[len(targs)-1] + + default: + panic(fmt.Sprintf("%s: unexpected type expression %v", expr.Pos(), syntax.String(expr))) + } + } +} + +func lastFieldType(fields []*syntax.Field) syntax.Expr { + if len(fields) == 0 { + return nil + } + return fields[len(fields)-1].Type +} + +// sumPos returns the position that noder.sum would produce for +// constant expression x. +func sumPos(x syntax.Expr) syntax.Pos { + orig := x + for { + switch x1 := x.(type) { + case *syntax.BasicLit: + assert(x1.Kind == syntax.StringLit) + return x1.Pos() + case *syntax.Operation: + assert(x1.Op == syntax.Add && x1.Y != nil) + if r, ok := x1.Y.(*syntax.BasicLit); ok { + assert(r.Kind == syntax.StringLit) + x = x1.X + continue + } + } + return orig.Pos() + } +} + +// funcParamsEndPos returns the value of base.Pos left by noder after +// processing a function signature. +func funcParamsEndPos(fn *ir.Func) src.XPos { + sig := fn.Nname.Type() + + fields := sig.Results().FieldSlice() + if len(fields) == 0 { + fields = sig.Params().FieldSlice() + if len(fields) == 0 { + fields = sig.Recvs().FieldSlice() + if len(fields) == 0 { + if fn.OClosure != nil { + return fn.Nname.Ntype.Pos() + } + return fn.Pos() + } + } + } + + return fields[len(fields)-1].Pos +} + +type dupTypes struct { + origs map[types2.Type]types2.Type +} + +func (d *dupTypes) orig(t types2.Type) types2.Type { + if orig, ok := d.origs[t]; ok { + return orig + } + return t +} + +func (d *dupTypes) add(t, orig types2.Type) { + if t == orig { + return + } + + if d.origs == nil { + d.origs = make(map[types2.Type]types2.Type) + } + assert(d.origs[t] == nil) + d.origs[t] = orig + + switch t := t.(type) { + case *types2.Pointer: + orig := orig.(*types2.Pointer) + d.add(t.Elem(), orig.Elem()) + + case *types2.Slice: + orig := orig.(*types2.Slice) + d.add(t.Elem(), orig.Elem()) + + case *types2.Map: + orig := orig.(*types2.Map) + d.add(t.Key(), orig.Key()) + d.add(t.Elem(), orig.Elem()) + + case *types2.Array: + orig := orig.(*types2.Array) + assert(t.Len() == orig.Len()) + d.add(t.Elem(), orig.Elem()) + + case *types2.Chan: + orig := orig.(*types2.Chan) + assert(t.Dir() == orig.Dir()) + d.add(t.Elem(), orig.Elem()) + + case *types2.Struct: + orig := orig.(*types2.Struct) + assert(t.NumFields() == orig.NumFields()) + for i := 0; i < t.NumFields(); i++ { + d.add(t.Field(i).Type(), orig.Field(i).Type()) + } + + case *types2.Interface: + orig := orig.(*types2.Interface) + assert(t.NumExplicitMethods() == orig.NumExplicitMethods()) + assert(t.NumEmbeddeds() == orig.NumEmbeddeds()) + for i := 0; i < t.NumExplicitMethods(); i++ { + d.add(t.ExplicitMethod(i).Type(), orig.ExplicitMethod(i).Type()) + } + for i := 0; i < t.NumEmbeddeds(); i++ { + d.add(t.EmbeddedType(i), orig.EmbeddedType(i)) + } + + case *types2.Signature: + orig := orig.(*types2.Signature) + assert((t.Recv() == nil) == (orig.Recv() == nil)) + if t.Recv() != nil { + d.add(t.Recv().Type(), orig.Recv().Type()) + } + d.add(t.Params(), orig.Params()) + d.add(t.Results(), orig.Results()) + + case *types2.Tuple: + orig := orig.(*types2.Tuple) + assert(t.Len() == orig.Len()) + for i := 0; i < t.Len(); i++ { + d.add(t.At(i).Type(), orig.At(i).Type()) + } + + default: + assert(types2.Identical(t, orig)) + } +} diff --git a/src/cmd/compile/internal/noder/reader.go b/src/cmd/compile/internal/noder/reader.go new file mode 100644 index 0000000000..18ecbff3cc --- /dev/null +++ b/src/cmd/compile/internal/noder/reader.go @@ -0,0 +1,1970 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "bytes" + "fmt" + "go/constant" + "strings" + + "cmd/compile/internal/base" + "cmd/compile/internal/deadcode" + "cmd/compile/internal/dwarfgen" + "cmd/compile/internal/ir" + "cmd/compile/internal/typecheck" + "cmd/compile/internal/types" + "cmd/internal/obj" + "cmd/internal/src" +) + +// TODO(mdempsky): Suppress duplicate type/const errors that can arise +// during typecheck due to naive type substitution (e.g., see #42758). +// I anticipate these will be handled as a consequence of adding +// dictionaries support, so it's probably not important to focus on +// this until after that's done. + +type pkgReader struct { + pkgDecoder + + posBases []*src.PosBase + pkgs []*types.Pkg + typs []*types.Type + + // offset for rewriting the given index into the output, + // but bitwise inverted so we can detect if we're missing the entry or not. + newindex []int +} + +func newPkgReader(pr pkgDecoder) *pkgReader { + return &pkgReader{ + pkgDecoder: pr, + + posBases: make([]*src.PosBase, pr.numElems(relocPosBase)), + pkgs: make([]*types.Pkg, pr.numElems(relocPkg)), + typs: make([]*types.Type, pr.numElems(relocType)), + + newindex: make([]int, pr.totalElems()), + } +} + +type pkgReaderIndex struct { + pr *pkgReader + idx int + implicits []*types.Type +} + +func (pri pkgReaderIndex) asReader(k reloc, marker syncMarker) *reader { + r := pri.pr.newReader(k, pri.idx, marker) + r.implicits = pri.implicits + return r +} + +func (pr *pkgReader) newReader(k reloc, idx int, marker syncMarker) *reader { + return &reader{ + decoder: pr.newDecoder(k, idx, marker), + p: pr, + } +} + +type reader struct { + decoder + + p *pkgReader + + // Implicit and explicit type arguments in use for reading the + // current object. For example: + // + // func F[T any]() { + // type X[U any] struct { t T; u U } + // var _ X[string] + // } + // + // var _ = F[int] + // + // While instantiating F[int], we need to in turn instantiate + // X[string]. [int] and [string] are explicit type arguments for F + // and X, respectively; but [int] is also the implicit type + // arguments for X. + // + // (As an analogy to function literals, explicits are the function + // literal's formal parameters, while implicits are variables + // captured by the function literal.) + implicits []*types.Type + explicits []*types.Type + + ext *reader + + // TODO(mdempsky): The state below is all specific to reading + // function bodies. It probably makes sense to split it out + // separately so that it doesn't take up space in every reader + // instance. + + curfn *ir.Func + locals []*ir.Name + + funarghack bool + + // scopeVars is a stack tracking the number of variables declared in + // the current function at the moment each open scope was opened. + scopeVars []int + marker dwarfgen.ScopeMarker + lastCloseScopePos src.XPos + + // === details for handling inline body expansion === + + // If we're reading in a function body because of inlining, this is + // the call that we're inlining for. + inlCaller *ir.Func + inlCall *ir.CallExpr + inlFunc *ir.Func + inlTreeIndex int + inlPosBases map[*src.PosBase]*src.PosBase + + delayResults bool + + // Label to return to. + retlabel *types.Sym + + inlvars, retvars ir.Nodes +} + +func (r *reader) setType(n ir.Node, typ *types.Type) { + n.SetType(typ) + n.SetTypecheck(1) + + if name, ok := n.(*ir.Name); ok { + name.SetWalkdef(1) + name.Ntype = ir.TypeNode(name.Type()) + } +} + +func (r *reader) setValue(name *ir.Name, val constant.Value) { + name.SetVal(val) + name.Defn = nil +} + +// @@@ Positions + +func (r *reader) pos() src.XPos { + return base.Ctxt.PosTable.XPos(r.pos0()) +} + +func (r *reader) pos0() src.Pos { + r.sync(syncPos) + if !r.bool() { + return src.NoPos + } + + posBase := r.posBase() + line := r.uint() + col := r.uint() + return src.MakePos(posBase, line, col) +} + +func (r *reader) posBase() *src.PosBase { + return r.inlPosBase(r.p.posBaseIdx(r.reloc(relocPosBase))) +} + +func (pr *pkgReader) posBaseIdx(idx int) *src.PosBase { + if b := pr.posBases[idx]; b != nil { + return b + } + + r := pr.newReader(relocPosBase, idx, syncPosBase) + var b *src.PosBase + + fn := r.string() + absfn := r.string() + + if r.bool() { + b = src.NewFileBase(fn, absfn) + } else { + pos := r.pos0() + line := r.uint() + col := r.uint() + b = src.NewLinePragmaBase(pos, fn, absfn, line, col) + } + + pr.posBases[idx] = b + return b +} + +func (r *reader) inlPosBase(oldBase *src.PosBase) *src.PosBase { + if r.inlCall == nil { + return oldBase + } + + if newBase, ok := r.inlPosBases[oldBase]; ok { + return newBase + } + + newBase := src.NewInliningBase(oldBase, r.inlTreeIndex) + r.inlPosBases[oldBase] = newBase + return newBase +} + +func (r *reader) updatePos(xpos src.XPos) src.XPos { + pos := base.Ctxt.PosTable.Pos(xpos) + pos.SetBase(r.inlPosBase(pos.Base())) + return base.Ctxt.PosTable.XPos(pos) +} + +func (r *reader) origPos(xpos src.XPos) src.XPos { + if r.inlCall == nil { + return xpos + } + + pos := base.Ctxt.PosTable.Pos(xpos) + for old, new := range r.inlPosBases { + if pos.Base() == new { + pos.SetBase(old) + return base.Ctxt.PosTable.XPos(pos) + } + } + + base.FatalfAt(xpos, "pos base missing from inlPosBases") + panic("unreachable") +} + +// @@@ Packages + +func (r *reader) pkg() *types.Pkg { + r.sync(syncPkg) + return r.p.pkgIdx(r.reloc(relocPkg)) +} + +func (pr *pkgReader) pkgIdx(idx int) *types.Pkg { + if pkg := pr.pkgs[idx]; pkg != nil { + return pkg + } + + pkg := pr.newReader(relocPkg, idx, syncPkgDef).doPkg() + pr.pkgs[idx] = pkg + return pkg +} + +func (r *reader) doPkg() *types.Pkg { + path := r.string() + if path == "builtin" { + return types.BuiltinPkg + } + if path == "" { + path = r.p.pkgPath + } + + name := r.string() + height := r.len() + + pkg := types.NewPkg(path, "") + + if pkg.Name == "" { + pkg.Name = name + } else { + assert(pkg.Name == name) + } + + if pkg.Height == 0 { + pkg.Height = height + } else { + assert(pkg.Height == height) + } + + return pkg +} + +// @@@ Types + +func (r *reader) typ() *types.Type { + r.sync(syncType) + return r.p.typIdx(r.reloc(relocType), r.implicits, r.explicits) +} + +func (pr *pkgReader) typIdx(idx int, implicits, explicits []*types.Type) *types.Type { + if typ := pr.typs[idx]; typ != nil { + return typ + } + + r := pr.newReader(relocType, idx, syncTypeIdx) + r.implicits = implicits + r.explicits = explicits + typ := r.doTyp() + assert(typ != nil) + + if typ := pr.typs[idx]; typ != nil { + // This happens in fixedbugs/issue27232.go. + // TODO(mdempsky): Explain why/how this happens. + return typ + } + + // If we have type parameters, the type might refer to them, and it + // wouldn't be safe to reuse those in other contexts. So we + // conservatively avoid caching them in that case. + // + // TODO(mdempsky): If we're clever, we should be able to still cache + // types by tracking which type parameters are used. However, in my + // attempts so far, I haven't yet succeeded in being clever enough. + if len(implicits)+len(explicits) == 0 { + pr.typs[idx] = typ + } + + if !typ.IsUntyped() { + types.CheckSize(typ) + } + + return typ +} + +func (r *reader) doTyp() *types.Type { + switch tag := codeType(r.code(syncType)); tag { + default: + panic(fmt.Sprintf("unexpected type: %v", tag)) + + case typeBasic: + return *basics[r.len()] + + case typeNamed: + obj := r.obj() + assert(obj.Op() == ir.OTYPE) + return obj.Type() + + case typeTypeParam: + idx := r.len() + if idx < len(r.implicits) { + return r.implicits[idx] + } + return r.explicits[idx-len(r.implicits)] + + case typeArray: + len := int64(r.uint64()) + return types.NewArray(r.typ(), len) + case typeChan: + dir := dirs[r.len()] + return types.NewChan(r.typ(), dir) + case typeMap: + return types.NewMap(r.typ(), r.typ()) + case typePointer: + return types.NewPtr(r.typ()) + case typeSignature: + return r.signature(types.LocalPkg, nil) + case typeSlice: + return types.NewSlice(r.typ()) + case typeStruct: + return r.structType() + case typeInterface: + return r.interfaceType() + } +} + +func (r *reader) interfaceType() *types.Type { + tpkg := types.LocalPkg // TODO(mdempsky): Remove after iexport is gone. + + nmethods, nembeddeds := r.len(), r.len() + + fields := make([]*types.Field, nmethods+nembeddeds) + methods, embeddeds := fields[:nmethods], fields[nmethods:] + + for i := range methods { + pos := r.pos() + pkg, sym := r.selector() + tpkg = pkg + mtyp := r.signature(pkg, typecheck.FakeRecv()) + methods[i] = types.NewField(pos, sym, mtyp) + } + for i := range embeddeds { + embeddeds[i] = types.NewField(src.NoXPos, nil, r.typ()) + } + + if len(fields) == 0 { + return types.Types[types.TINTER] // empty interface + } + return types.NewInterface(tpkg, fields) +} + +func (r *reader) structType() *types.Type { + tpkg := types.LocalPkg // TODO(mdempsky): Remove after iexport is gone. + fields := make([]*types.Field, r.len()) + for i := range fields { + pos := r.pos() + pkg, sym := r.selector() + tpkg = pkg + ftyp := r.typ() + tag := r.string() + embedded := r.bool() + + f := types.NewField(pos, sym, ftyp) + f.Note = tag + if embedded { + f.Embedded = 1 + } + fields[i] = f + } + return types.NewStruct(tpkg, fields) +} + +func (r *reader) signature(tpkg *types.Pkg, recv *types.Field) *types.Type { + r.sync(syncSignature) + + params := r.params(&tpkg) + results := r.params(&tpkg) + if r.bool() { // variadic + params[len(params)-1].SetIsDDD(true) + } + + return types.NewSignature(tpkg, recv, nil, params, results) +} + +func (r *reader) params(tpkg **types.Pkg) []*types.Field { + r.sync(syncParams) + fields := make([]*types.Field, r.len()) + for i := range fields { + *tpkg, fields[i] = r.param() + } + return fields +} + +func (r *reader) param() (*types.Pkg, *types.Field) { + r.sync(syncParam) + + pos := r.pos() + pkg, sym := r.localIdent() + typ := r.typ() + + return pkg, types.NewField(pos, sym, typ) +} + +// @@@ Objects + +var objReader = map[*types.Sym]pkgReaderIndex{} + +func (r *reader) obj() ir.Node { + r.sync(syncObject) + + idx := r.reloc(relocObj) + + explicits := make([]*types.Type, r.len()) + for i := range explicits { + explicits[i] = r.typ() + } + + return r.p.objIdx(idx, r.implicits, explicits) +} + +func (pr *pkgReader) objIdx(idx int, implicits, explicits []*types.Type) ir.Node { + r := pr.newReader(relocObj, idx, syncObject1) + r.ext = pr.newReader(relocObjExt, idx, syncObject1) + + _, sym := r.qualifiedIdent() + + // Middle dot indicates local defined type; see writer.sym. + // TODO(mdempsky): Come up with a better way to handle this. + if strings.Contains(sym.Name, "·") { + r.implicits = implicits + r.ext.implicits = implicits + } + r.explicits = explicits + r.ext.explicits = explicits + + origSym := sym + + sym = r.mangle(sym) + if !sym.IsBlank() && sym.Def != nil { + return sym.Def.(ir.Node) + } + + r.typeParamBounds(origSym) + tag := codeObj(r.code(syncCodeObj)) + + do := func(op ir.Op, hasTParams bool) *ir.Name { + pos := r.pos() + if hasTParams { + r.typeParamNames() + } + + name := ir.NewDeclNameAt(pos, op, sym) + name.Class = ir.PEXTERN // may be overridden later + if !sym.IsBlank() { + if sym.Def != nil { + base.FatalfAt(name.Pos(), "already have a definition for %v", name) + } + assert(sym.Def == nil) + sym.Def = name + } + return name + } + + switch tag { + default: + panic("unexpected object") + + case objStub: + if pri, ok := objReader[origSym]; ok { + return pri.pr.objIdx(pri.idx, pri.implicits, r.explicits) + } + if haveLegacyImports { + assert(len(r.implicits)+len(r.explicits) == 0) + return typecheck.Resolve(ir.NewIdent(src.NoXPos, origSym)) + } + base.Fatalf("unresolved stub: %v", origSym) + panic("unreachable") + + case objAlias: + name := do(ir.OTYPE, false) + r.setType(name, r.typ()) + name.SetAlias(true) + return name + + case objConst: + name := do(ir.OLITERAL, false) + typ, val := r.value() + r.setType(name, typ) + r.setValue(name, val) + return name + + case objFunc: + if sym.Name == "init" { + sym = renameinit() + } + name := do(ir.ONAME, true) + r.setType(name, r.signature(sym.Pkg, nil)) + + name.Func = ir.NewFunc(r.pos()) + name.Func.Nname = name + + r.ext.funcExt(name) + return name + + case objType: + name := do(ir.OTYPE, true) + typ := types.NewNamed(name) + r.setType(name, typ) + + // Important: We need to do this before SetUnderlying. + r.ext.typeExt(name) + + // We need to defer CheckSize until we've called SetUnderlying to + // handle recursive types. + types.DeferCheckSize() + typ.SetUnderlying(r.typ()) + types.ResumeCheckSize() + + methods := make([]*types.Field, r.len()) + for i := range methods { + methods[i] = r.method() + } + if len(methods) != 0 { + typ.Methods().Set(methods) + } + + return name + + case objVar: + name := do(ir.ONAME, false) + r.setType(name, r.typ()) + r.ext.varExt(name) + return name + } +} + +func (r *reader) mangle(sym *types.Sym) *types.Sym { + if len(r.implicits)+len(r.explicits) == 0 { + return sym + } + + var buf bytes.Buffer + buf.WriteString(sym.Name) + buf.WriteByte('[') + for i, targs := range [2][]*types.Type{r.implicits, r.explicits} { + if i > 0 && len(r.implicits) != 0 && len(r.explicits) != 0 { + buf.WriteByte(';') + } + for j, targ := range targs { + if j > 0 { + buf.WriteByte(',') + } + // TODO(mdempsky): We need the linker to replace "" in the symbol + // names here. + buf.WriteString(targ.ShortString()) + } + } + buf.WriteByte(']') + return sym.Pkg.Lookup(buf.String()) +} + +func (r *reader) typeParamBounds(sym *types.Sym) { + r.sync(syncTypeParamBounds) + + nimplicits := r.len() + nexplicits := r.len() + + if len(r.implicits) != nimplicits || len(r.explicits) != nexplicits { + base.Fatalf("%v has %v+%v params, but instantiated with %v+%v args", sym, nimplicits, nexplicits, len(r.implicits), len(r.explicits)) + } + + // For stenciling, we can just skip over the type parameters. + + for range r.explicits { + // Skip past bounds without actually evaluating them. + r.sync(syncType) + r.reloc(relocType) + } +} + +func (r *reader) typeParamNames() { + r.sync(syncTypeParamNames) + + for range r.explicits { + r.pos() + r.localIdent() + } +} + +func (r *reader) value() (*types.Type, constant.Value) { + r.sync(syncValue) + typ := r.typ() + return typ, FixValue(typ, r.rawValue()) +} + +func (r *reader) method() *types.Field { + r.sync(syncMethod) + pos := r.pos() + pkg, sym := r.selector() + r.typeParamNames() + _, recv := r.param() + typ := r.signature(pkg, recv) + + fnsym := sym + fnsym = ir.MethodSym(recv.Type, fnsym) + name := ir.NewNameAt(pos, fnsym) + r.setType(name, typ) + + name.Func = ir.NewFunc(r.pos()) + name.Func.Nname = name + + // TODO(mdempsky): Make sure we're handling //go:nointerface + // correctly. I don't think this is exercised within the Go repo. + + r.ext.funcExt(name) + + meth := types.NewField(name.Func.Pos(), sym, typ) + meth.Nname = name + return meth +} + +func (r *reader) qualifiedIdent() (pkg *types.Pkg, sym *types.Sym) { + r.sync(syncSym) + pkg = r.pkg() + if name := r.string(); name != "" { + sym = pkg.Lookup(name) + } + return +} + +func (r *reader) localIdent() (pkg *types.Pkg, sym *types.Sym) { + r.sync(syncLocalIdent) + pkg = r.pkg() + if name := r.string(); name != "" { + sym = pkg.Lookup(name) + } + return +} + +func (r *reader) selector() (origPkg *types.Pkg, sym *types.Sym) { + r.sync(syncSelector) + origPkg = r.pkg() + name := r.string() + pkg := origPkg + if types.IsExported(name) { + pkg = types.LocalPkg + } + sym = pkg.Lookup(name) + return +} + +// @@@ Compiler extensions + +func (r *reader) funcExt(name *ir.Name) { + r.sync(syncFuncExt) + + name.Class = 0 // so MarkFunc doesn't complain + ir.MarkFunc(name) + + fn := name.Func + + // XXX: Workaround because linker doesn't know how to copy Pos. + if !fn.Pos().IsKnown() { + fn.SetPos(name.Pos()) + } + + // TODO(mdempsky): Remember why I wrote this code. I think it has to + // do with how ir.VisitFuncsBottomUp works? + if name.Sym().Pkg == types.LocalPkg || len(r.implicits)+len(r.explicits) != 0 { + name.Defn = fn + } + + fn.Pragma = r.pragmaFlag() + r.linkname(name) + + if r.bool() { + fn.ABI = obj.ABI(r.uint64()) + + // Escape analysis. + for _, fs := range &types.RecvsParams { + for _, f := range fs(name.Type()).FieldSlice() { + f.Note = r.string() + } + } + + if r.bool() { + fn.Inl = &ir.Inline{ + Cost: int32(r.len()), + CanDelayResults: r.bool(), + } + r.addBody(name.Func) + } + } else { + r.addBody(name.Func) + } + r.sync(syncEOF) +} + +func (r *reader) typeExt(name *ir.Name) { + r.sync(syncTypeExt) + + typ := name.Type() + + if len(r.implicits)+len(r.explicits) != 0 { + // Set "RParams" (really type arguments here, not parameters) so + // this type is treated as "fully instantiated". This ensures the + // type descriptor is written out as DUPOK and method wrappers are + // generated even for imported types. + var targs []*types.Type + targs = append(targs, r.implicits...) + targs = append(targs, r.explicits...) + typ.SetRParams(targs) + } + + name.SetPragma(r.pragmaFlag()) + if name.Pragma()&ir.NotInHeap != 0 { + typ.SetNotInHeap(true) + } + + typecheck.SetBaseTypeIndex(typ, r.int64(), r.int64()) +} + +func (r *reader) varExt(name *ir.Name) { + r.sync(syncVarExt) + r.linkname(name) +} + +func (r *reader) linkname(name *ir.Name) { + assert(name.Op() == ir.ONAME) + r.sync(syncLinkname) + + if idx := r.int64(); idx >= 0 { + lsym := name.Linksym() + lsym.SymIdx = int32(idx) + lsym.Set(obj.AttrIndexed, true) + } else { + name.Sym().Linkname = r.string() + } +} + +func (r *reader) pragmaFlag() ir.PragmaFlag { + r.sync(syncPragma) + return ir.PragmaFlag(r.int()) +} + +// @@@ Function bodies + +// bodyReader tracks where the serialized IR for a function's body can +// be found. +var bodyReader = map[*ir.Func]pkgReaderIndex{} + +// todoBodies holds the list of function bodies that still need to be +// constructed. +var todoBodies []*ir.Func + +func (r *reader) addBody(fn *ir.Func) { + r.sync(syncAddBody) + + // See commont in writer.addBody for why r.implicits and r.explicits + // should never both be non-empty. + implicits := r.implicits + if len(implicits) == 0 { + implicits = r.explicits + } else { + assert(len(r.explicits) == 0) + } + + pri := pkgReaderIndex{r.p, r.reloc(relocBody), implicits} + bodyReader[fn] = pri + + if r.curfn == nil { + todoBodies = append(todoBodies, fn) + return + } + + pri.funcBody(fn) +} + +func (pri pkgReaderIndex) funcBody(fn *ir.Func) { + r := pri.asReader(relocBody, syncFuncBody) + r.funcBody(fn) +} + +func (r *reader) funcBody(fn *ir.Func) { + r.curfn = fn + r.locals = fn.ClosureVars + + // TODO(mdempsky): Get rid of uses of typecheck.NodAddrAt so we + // don't have to set ir.CurFunc. + outerCurFunc := ir.CurFunc + ir.CurFunc = fn + + r.funcargs(fn) + + if r.bool() { + body := r.stmts() + if body == nil { + pos := src.NoXPos + if quirksMode() { + pos = funcParamsEndPos(fn) + } + body = []ir.Node{ir.NewBlockStmt(pos, nil)} + } + fn.Body = body + fn.Endlineno = r.pos() + } + + ir.CurFunc = outerCurFunc + r.marker.WriteTo(fn) +} + +func (r *reader) funcargs(fn *ir.Func) { + sig := fn.Nname.Type() + + if recv := sig.Recv(); recv != nil { + r.funcarg(recv, recv.Sym, ir.PPARAM) + } + for _, param := range sig.Params().FieldSlice() { + r.funcarg(param, param.Sym, ir.PPARAM) + } + + for i, param := range sig.Results().FieldSlice() { + sym := types.OrigSym(param.Sym) + + if sym == nil || sym.IsBlank() { + prefix := "~r" + if r.inlCall != nil { + prefix = "~R" + } else if sym != nil { + prefix = "~b" + } + sym = typecheck.LookupNum(prefix, i) + } + + r.funcarg(param, sym, ir.PPARAMOUT) + } +} + +func (r *reader) funcarg(param *types.Field, sym *types.Sym, ctxt ir.Class) { + if sym == nil { + assert(ctxt == ir.PPARAM) + if r.inlCall != nil { + r.inlvars.Append(ir.BlankNode) + } + return + } + + name := ir.NewNameAt(r.updatePos(param.Pos), sym) + r.setType(name, param.Type) + r.addLocal(name, ctxt) + + if r.inlCall == nil { + if !r.funarghack { + param.Sym = sym + param.Nname = name + } + } else { + if ctxt == ir.PPARAMOUT { + r.retvars.Append(name) + } else { + r.inlvars.Append(name) + } + } +} + +func (r *reader) addLocal(name *ir.Name, ctxt ir.Class) { + assert(ctxt == ir.PAUTO || ctxt == ir.PPARAM || ctxt == ir.PPARAMOUT) + + r.sync(syncAddLocal) + if debug { + want := r.int() + if have := len(r.locals); have != want { + base.FatalfAt(name.Pos(), "locals table has desynced") + } + } + + name.SetUsed(true) + r.locals = append(r.locals, name) + + // TODO(mdempsky): Move earlier. + if ir.IsBlank(name) { + return + } + + if r.inlCall != nil { + if ctxt == ir.PAUTO { + name.SetInlLocal(true) + } else { + name.SetInlFormal(true) + ctxt = ir.PAUTO + } + + // TODO(mdempsky): Rethink this hack. + if strings.HasPrefix(name.Sym().Name, "~") || base.Flag.GenDwarfInl == 0 { + name.SetPos(r.inlCall.Pos()) + name.SetInlFormal(false) + name.SetInlLocal(false) + } + } + + name.Class = ctxt + name.Curfn = r.curfn + + r.curfn.Dcl = append(r.curfn.Dcl, name) + + if ctxt == ir.PAUTO { + name.SetFrameOffset(0) + } +} + +func (r *reader) useLocal() *ir.Name { + r.sync(syncUseObjLocal) + return r.locals[r.len()] +} + +func (r *reader) openScope() { + r.sync(syncOpenScope) + pos := r.pos() + + if base.Flag.Dwarf { + r.scopeVars = append(r.scopeVars, len(r.curfn.Dcl)) + r.marker.Push(pos) + } +} + +func (r *reader) closeScope() { + r.sync(syncCloseScope) + r.lastCloseScopePos = r.pos() + + r.closeAnotherScope() +} + +// closeAnotherScope is like closeScope, but it reuses the same mark +// position as the last closeScope call. This is useful for "for" and +// "if" statements, as their implicit blocks always end at the same +// position as an explicit block. +func (r *reader) closeAnotherScope() { + r.sync(syncCloseAnotherScope) + + if base.Flag.Dwarf { + scopeVars := r.scopeVars[len(r.scopeVars)-1] + r.scopeVars = r.scopeVars[:len(r.scopeVars)-1] + + if scopeVars == len(r.curfn.Dcl) { + // no variables were declared in this scope, so we can retract it. + r.marker.Unpush() + } else { + r.marker.Pop(r.lastCloseScopePos) + } + } +} + +// @@@ Statements + +func (r *reader) stmt() ir.Node { + switch stmts := r.stmts(); len(stmts) { + case 0: + return nil + case 1: + return stmts[0] + default: + return ir.NewBlockStmt(stmts[0].Pos(), stmts) + } +} + +func (r *reader) stmts() []ir.Node { + var res ir.Nodes + + r.sync(syncStmts) + for { + tag := codeStmt(r.code(syncStmt1)) + if tag == stmtEnd { + r.sync(syncStmtsEnd) + return res + } + + if n := r.stmt1(tag, &res); n != nil { + res.Append(n) + } + } +} + +func (r *reader) stmt1(tag codeStmt, out *ir.Nodes) ir.Node { + var label *types.Sym + if n := len(*out); n > 0 { + if ls, ok := (*out)[n-1].(*ir.LabelStmt); ok { + label = ls.Label + } + } + + switch tag { + default: + panic("unexpected statement") + + case stmtAssign: + pos := r.pos() + names, lhs := r.assignList() + rhs := r.exprList() + + if len(rhs) == 0 { + for _, name := range names { + as := ir.NewAssignStmt(pos, name, nil) + as.PtrInit().Append(ir.NewDecl(pos, ir.ODCL, name)) + out.Append(as) + } + return nil + } + + if len(lhs) == 1 && len(rhs) == 1 { + n := ir.NewAssignStmt(pos, lhs[0], rhs[0]) + n.Def = r.initDefn(n, names) + return n + } + + n := ir.NewAssignListStmt(pos, ir.OAS2, lhs, rhs) + n.Def = r.initDefn(n, names) + return n + + case stmtAssignOp: + op := r.op() + lhs := r.expr() + pos := r.pos() + rhs := r.expr() + return ir.NewAssignOpStmt(pos, op, lhs, rhs) + + case stmtIncDec: + op := r.op() + lhs := r.expr() + pos := r.pos() + n := ir.NewAssignOpStmt(pos, op, lhs, ir.NewBasicLit(pos, one)) + n.IncDec = true + return n + + case stmtBlock: + out.Append(r.blockStmt()...) + return nil + + case stmtBranch: + pos := r.pos() + op := r.op() + sym := r.optLabel() + return ir.NewBranchStmt(pos, op, sym) + + case stmtCall: + pos := r.pos() + op := r.op() + call := r.expr() + return ir.NewGoDeferStmt(pos, op, call) + + case stmtExpr: + return r.expr() + + case stmtFor: + return r.forStmt(label) + + case stmtIf: + return r.ifStmt() + + case stmtLabel: + pos := r.pos() + sym := r.label() + return ir.NewLabelStmt(pos, sym) + + case stmtReturn: + pos := r.pos() + results := r.exprList() + return ir.NewReturnStmt(pos, results) + + case stmtSelect: + return r.selectStmt(label) + + case stmtSend: + pos := r.pos() + ch := r.expr() + value := r.expr() + return ir.NewSendStmt(pos, ch, value) + + case stmtSwitch: + return r.switchStmt(label) + + case stmtTypeDeclHack: + // fake "type _ = int" declaration to prevent inlining in quirks mode. + assert(quirksMode()) + + name := ir.NewDeclNameAt(src.NoXPos, ir.OTYPE, ir.BlankNode.Sym()) + name.SetAlias(true) + r.setType(name, types.Types[types.TINT]) + + n := ir.NewDecl(src.NoXPos, ir.ODCLTYPE, name) + n.SetTypecheck(1) + return n + } +} + +func (r *reader) assignList() ([]*ir.Name, []ir.Node) { + lhs := make([]ir.Node, r.len()) + var names []*ir.Name + + for i := range lhs { + if r.bool() { + pos := r.pos() + _, sym := r.localIdent() + typ := r.typ() + + name := ir.NewNameAt(pos, sym) + lhs[i] = name + names = append(names, name) + r.setType(name, typ) + r.addLocal(name, ir.PAUTO) + continue + } + + lhs[i] = r.expr() + } + + return names, lhs +} + +func (r *reader) blockStmt() []ir.Node { + r.sync(syncBlockStmt) + r.openScope() + stmts := r.stmts() + r.closeScope() + return stmts +} + +func (r *reader) forStmt(label *types.Sym) ir.Node { + r.sync(syncForStmt) + + r.openScope() + + if r.bool() { + pos := r.pos() + names, lhs := r.assignList() + x := r.expr() + body := r.blockStmt() + r.closeAnotherScope() + + rang := ir.NewRangeStmt(pos, nil, nil, x, body) + if len(lhs) >= 1 { + rang.Key = lhs[0] + if len(lhs) >= 2 { + rang.Value = lhs[1] + } + } + rang.Def = r.initDefn(rang, names) + rang.Label = label + return rang + } + + pos := r.pos() + init := r.stmt() + cond := r.expr() + post := r.stmt() + body := r.blockStmt() + r.closeAnotherScope() + + stmt := ir.NewForStmt(pos, init, cond, post, body) + stmt.Label = label + return stmt +} + +func (r *reader) ifStmt() ir.Node { + r.sync(syncIfStmt) + r.openScope() + pos := r.pos() + init := r.stmts() + cond := r.expr() + then := r.blockStmt() + els := r.stmts() + n := ir.NewIfStmt(pos, cond, then, els) + n.SetInit(init) + r.closeAnotherScope() + return n +} + +func (r *reader) selectStmt(label *types.Sym) ir.Node { + r.sync(syncSelectStmt) + + pos := r.pos() + clauses := make([]*ir.CommClause, r.len()) + for i := range clauses { + if i > 0 { + r.closeScope() + } + r.openScope() + + pos := r.pos() + comm := r.stmt() + body := r.stmts() + + clauses[i] = ir.NewCommStmt(pos, comm, body) + } + if len(clauses) > 0 { + r.closeScope() + } + n := ir.NewSelectStmt(pos, clauses) + n.Label = label + return n +} + +func (r *reader) switchStmt(label *types.Sym) ir.Node { + r.sync(syncSwitchStmt) + + r.openScope() + pos := r.pos() + init := r.stmt() + tag := r.expr() + + tswitch, ok := tag.(*ir.TypeSwitchGuard) + if ok && tswitch.Tag == nil { + tswitch = nil + } + + clauses := make([]*ir.CaseClause, r.len()) + for i := range clauses { + if i > 0 { + r.closeScope() + } + r.openScope() + + pos := r.pos() + cases := r.exprList() + + clause := ir.NewCaseStmt(pos, cases, nil) + if tswitch != nil { + pos := r.pos() + typ := r.typ() + + name := ir.NewNameAt(pos, tswitch.Tag.Sym()) + r.setType(name, typ) + r.addLocal(name, ir.PAUTO) + clause.Var = name + name.Defn = tswitch + } + + clause.Body = r.stmts() + clauses[i] = clause + } + if len(clauses) > 0 { + r.closeScope() + } + r.closeScope() + + n := ir.NewSwitchStmt(pos, tag, clauses) + n.Label = label + if init != nil { + n.SetInit([]ir.Node{init}) + } + return n +} + +func (r *reader) label() *types.Sym { + r.sync(syncLabel) + name := r.string() + if r.inlCall != nil { + name = fmt.Sprintf("~%s·%d", name, inlgen) + } + return typecheck.Lookup(name) +} + +func (r *reader) optLabel() *types.Sym { + r.sync(syncOptLabel) + if r.bool() { + return r.label() + } + return nil +} + +// initDefn marks the given names as declared by defn and populates +// its Init field with ODCL nodes. It then reports whether any names +// were so declared, which can be used to initialize defn.Def. +func (r *reader) initDefn(defn ir.InitNode, names []*ir.Name) bool { + if len(names) == 0 { + return false + } + + init := make([]ir.Node, len(names)) + for i, name := range names { + name.Defn = defn + init[i] = ir.NewDecl(name.Pos(), ir.ODCL, name) + } + defn.SetInit(init) + return true +} + +// @@@ Expressions + +func (r *reader) expr() ir.Node { + switch tag := codeExpr(r.code(syncExpr)); tag { + default: + panic("unhandled expression") + + case exprNone: + return nil + + case exprBlank: + return ir.BlankNode + + case exprLocal: + return r.useLocal() + + case exprName: + return r.obj() + + case exprType: + return ir.TypeNode(r.typ()) + + case exprConst: + pos := r.pos() + typ, val := r.value() + op := r.op() + orig := r.string() + return OrigConst(pos, typ, val, op, orig) + + case exprCompLit: + return r.compLit() + + case exprFuncLit: + return r.funcLit() + + case exprSelector: + x := r.expr() + pos := r.pos() + _, sym := r.selector() + return ir.NewSelectorExpr(pos, ir.OXDOT, x, sym) + + case exprIndex: + x := r.expr() + pos := r.pos() + index := r.expr() + return ir.NewIndexExpr(pos, x, index) + + case exprSlice: + x := r.expr() + pos := r.pos() + var index [3]ir.Node + for i := range index { + index[i] = r.expr() + } + op := ir.OSLICE + if index[2] != nil { + op = ir.OSLICE3 + } + return ir.NewSliceExpr(pos, op, x, index[0], index[1], index[2]) + + case exprAssert: + x := r.expr() + pos := r.pos() + typ := r.expr().(ir.Ntype) + return ir.NewTypeAssertExpr(pos, x, typ) + + case exprUnaryOp: + op := r.op() + pos := r.pos() + x := r.expr() + + switch op { + case ir.OADDR: + return typecheck.NodAddrAt(pos, x) + case ir.ODEREF: + return ir.NewStarExpr(pos, x) + } + return ir.NewUnaryExpr(pos, op, x) + + case exprBinaryOp: + op := r.op() + x := r.expr() + pos := r.pos() + y := r.expr() + + switch op { + case ir.OANDAND, ir.OOROR: + return ir.NewLogicalExpr(pos, op, x, y) + } + return ir.NewBinaryExpr(pos, op, x, y) + + case exprCall: + fun := r.expr() + pos := r.pos() + args := r.exprs() + dots := r.bool() + n := ir.NewCallExpr(pos, ir.OCALL, fun, args) + n.IsDDD = dots + return n + + case exprTypeSwitchGuard: + pos := r.pos() + var tag *ir.Ident + if r.bool() { + pos := r.pos() + sym := typecheck.Lookup(r.string()) + tag = ir.NewIdent(pos, sym) + } + x := r.expr() + return ir.NewTypeSwitchGuard(pos, tag, x) + } +} + +func (r *reader) compLit() ir.Node { + r.sync(syncCompLit) + pos := r.pos() + typ := r.typ() + + isPtrLit := typ.IsPtr() + if isPtrLit { + typ = typ.Elem() + } + if typ.Kind() == types.TFORW { + base.FatalfAt(pos, "unresolved composite literal type: %v", typ) + } + isStruct := typ.Kind() == types.TSTRUCT + + elems := make([]ir.Node, r.len()) + for i := range elems { + elemp := &elems[i] + + if isStruct { + sk := ir.NewStructKeyExpr(r.pos(), typ.Field(r.len()), nil) + *elemp, elemp = sk, &sk.Value + } else if r.bool() { + kv := ir.NewKeyExpr(r.pos(), r.expr(), nil) + *elemp, elemp = kv, &kv.Value + } + + *elemp = wrapName(r.pos(), r.expr()) + } + + lit := ir.NewCompLitExpr(pos, ir.OCOMPLIT, ir.TypeNode(typ), elems) + if isPtrLit { + return typecheck.NodAddrAt(pos, lit) + } + return lit +} + +func wrapName(pos src.XPos, x ir.Node) ir.Node { + // These nodes do not carry line numbers. + // Introduce a wrapper node to give them the correct line. + switch ir.Orig(x).Op() { + case ir.OTYPE, ir.OLITERAL: + if x.Sym() == nil { + break + } + fallthrough + case ir.ONAME, ir.ONONAME, ir.OPACK, ir.ONIL: + p := ir.NewParenExpr(pos, x) + p.SetImplicit(true) + return p + } + return x +} + +func (r *reader) funcLit() ir.Node { + r.sync(syncFuncLit) + + pos := r.pos() + typPos := r.pos() + xtype2 := r.signature(types.LocalPkg, nil) + + opos := pos + if quirksMode() { + opos = r.origPos(pos) + } + + fn := ir.NewClosureFunc(opos, r.curfn != nil) + + r.setType(fn.Nname, xtype2) + if quirksMode() { + fn.Nname.Ntype = ir.TypeNodeAt(typPos, xtype2) + } + + fn.ClosureVars = make([]*ir.Name, r.len()) + for i := range fn.ClosureVars { + pos := r.pos() + outer := r.useLocal() + + cv := ir.NewNameAt(pos, outer.Sym()) + r.setType(cv, outer.Type()) + cv.Curfn = fn + cv.Class = ir.PAUTOHEAP + cv.SetIsClosureVar(true) + cv.Defn = outer.Canonical() + cv.Outer = outer + + fn.ClosureVars[i] = cv + } + + r.addBody(fn) + + return fn.OClosure +} + +func (r *reader) exprList() []ir.Node { + r.sync(syncExprList) + return r.exprs() +} + +func (r *reader) exprs() []ir.Node { + r.sync(syncExprs) + nodes := make([]ir.Node, r.len()) + if len(nodes) == 0 { + return nil // TODO(mdempsky): Unclear if this matters. + } + for i := range nodes { + nodes[i] = r.expr() + } + return nodes +} + +func (r *reader) op() ir.Op { + r.sync(syncOp) + return ir.Op(r.len()) +} + +// @@@ Package initialization + +func (r *reader) pkgInit(self *types.Pkg, target *ir.Package) { + if quirksMode() { + for i, n := 0, r.len(); i < n; i++ { + // Eagerly register position bases, so their filenames are + // assigned stable indices. + posBase := r.posBase() + _ = base.Ctxt.PosTable.XPos(src.MakePos(posBase, 0, 0)) + } + + for i, n := 0, r.len(); i < n; i++ { + // Eagerly resolve imported objects, so any filenames registered + // in the process are assigned stable indices too. + _, sym := r.qualifiedIdent() + typecheck.Resolve(ir.NewIdent(src.NoXPos, sym)) + assert(sym.Def != nil) + } + } + + cgoPragmas := make([][]string, r.len()) + for i := range cgoPragmas { + cgoPragmas[i] = r.strings() + } + target.CgoPragmas = cgoPragmas + + r.pkgDecls(target) + + r.sync(syncEOF) +} + +func (r *reader) pkgDecls(target *ir.Package) { + r.sync(syncDecls) + for { + switch code := codeDecl(r.code(syncDecl)); code { + default: + panic(fmt.Sprintf("unhandled decl: %v", code)) + + case declEnd: + return + + case declFunc: + names := r.pkgObjs(target) + assert(len(names) == 1) + target.Decls = append(target.Decls, names[0].Func) + + case declMethod: + typ := r.typ() + _, sym := r.selector() + + method := typecheck.Lookdot1(nil, sym, typ, typ.Methods(), 0) + target.Decls = append(target.Decls, method.Nname.(*ir.Name).Func) + + case declVar: + pos := r.pos() + names := r.pkgObjs(target) + values := r.exprList() + + if len(names) > 1 && len(values) == 1 { + as := ir.NewAssignListStmt(pos, ir.OAS2, nil, values) + for _, name := range names { + as.Lhs.Append(name) + name.Defn = as + } + target.Decls = append(target.Decls, as) + } else { + for i, name := range names { + as := ir.NewAssignStmt(pos, name, nil) + if i < len(values) { + as.Y = values[i] + } + name.Defn = as + target.Decls = append(target.Decls, as) + } + } + + if n := r.len(); n > 0 { + assert(len(names) == 1) + embeds := make([]ir.Embed, n) + for i := range embeds { + embeds[i] = ir.Embed{Pos: r.pos(), Patterns: r.strings()} + } + names[0].Embed = &embeds + target.Embeds = append(target.Embeds, names[0]) + } + + case declOther: + r.pkgObjs(target) + } + } +} + +func (r *reader) pkgObjs(target *ir.Package) []*ir.Name { + r.sync(syncDeclNames) + nodes := make([]*ir.Name, r.len()) + for i := range nodes { + r.sync(syncDeclName) + + name := r.obj().(*ir.Name) + nodes[i] = name + + sym := name.Sym() + if sym.IsBlank() { + continue + } + + switch name.Class { + default: + base.FatalfAt(name.Pos(), "unexpected class: %v", name.Class) + + case ir.PEXTERN: + target.Externs = append(target.Externs, name) + + case ir.PFUNC: + assert(name.Type().Recv() == nil) + + // TODO(mdempsky): Cleaner way to recognize init? + if strings.HasPrefix(sym.Name, "init.") { + target.Inits = append(target.Inits, name.Func) + } + } + + if types.IsExported(sym.Name) { + assert(!sym.OnExportList()) + target.Exports = append(target.Exports, name) + sym.SetOnExportList(true) + } + + if base.Flag.AsmHdr != "" { + assert(!sym.Asm()) + target.Asms = append(target.Asms, name) + sym.SetAsm(true) + } + } + + return nodes +} + +// @@@ Inlining + +var inlgen = 0 + +func InlineCall(call *ir.CallExpr, fn *ir.Func, inlIndex int) *ir.InlinedCallExpr { + // TODO(mdempsky): Turn callerfn into an explicit parameter. + callerfn := ir.CurFunc + + pri, ok := bodyReader[fn] + if !ok { + // Assume it's an imported function or something that we don't + // have access to in quirks mode. + if haveLegacyImports { + return nil + } + + base.FatalfAt(call.Pos(), "missing function body for call to %v", fn) + } + + if fn.Inl.Body == nil { + expandInline(fn, pri) + } + + r := pri.asReader(relocBody, syncFuncBody) + + // TODO(mdempsky): This still feels clumsy. Can we do better? + tmpfn := ir.NewFunc(fn.Pos()) + tmpfn.Nname = ir.NewNameAt(fn.Nname.Pos(), callerfn.Sym()) + tmpfn.Closgen = callerfn.Closgen + defer func() { callerfn.Closgen = tmpfn.Closgen }() + + r.setType(tmpfn.Nname, fn.Type()) + r.curfn = tmpfn + + r.inlCaller = ir.CurFunc + r.inlCall = call + r.inlFunc = fn + r.inlTreeIndex = inlIndex + r.inlPosBases = make(map[*src.PosBase]*src.PosBase) + + for _, cv := range r.inlFunc.ClosureVars { + r.locals = append(r.locals, cv.Outer) + } + + r.funcargs(fn) + + assert(r.bool()) // have body + r.delayResults = fn.Inl.CanDelayResults + + r.retlabel = typecheck.AutoLabel(".i") + inlgen++ + + init := ir.TakeInit(call) + + // For normal function calls, the function callee expression + // may contain side effects (e.g., added by addinit during + // inlconv2expr or inlconv2list). Make sure to preserve these, + // if necessary (#42703). + if call.Op() == ir.OCALLFUNC { + callee := call.X + for callee.Op() == ir.OCONVNOP { + conv := callee.(*ir.ConvExpr) + init.Append(ir.TakeInit(conv)...) + callee = conv.X + } + + switch callee.Op() { + case ir.ONAME, ir.OCLOSURE, ir.OMETHEXPR: + // ok + default: + base.Fatalf("unexpected callee expression: %v", callee) + } + } + + var args ir.Nodes + if call.Op() == ir.OCALLMETH { + assert(call.X.Op() == ir.ODOTMETH) + args.Append(call.X.(*ir.SelectorExpr).X) + } + args.Append(call.Args...) + + // Create assignment to declare and initialize inlvars. + as2 := ir.NewAssignListStmt(call.Pos(), ir.OAS2, r.inlvars, args) + as2.Def = true + var as2init ir.Nodes + for _, name := range r.inlvars { + if ir.IsBlank(name) { + continue + } + // TODO(mdempsky): Use inlined position of name.Pos() instead? + name := name.(*ir.Name) + as2init.Append(ir.NewDecl(call.Pos(), ir.ODCL, name)) + name.Defn = as2 + } + as2.SetInit(as2init) + init.Append(typecheck.Stmt(as2)) + + if !r.delayResults { + // If not delaying retvars, declare and zero initialize the + // result variables now. + for _, name := range r.retvars { + // TODO(mdempsky): Use inlined position of name.Pos() instead? + name := name.(*ir.Name) + init.Append(ir.NewDecl(call.Pos(), ir.ODCL, name)) + ras := ir.NewAssignStmt(call.Pos(), name, nil) + init.Append(typecheck.Stmt(ras)) + } + } + + // Add an inline mark just before the inlined body. + // This mark is inline in the code so that it's a reasonable spot + // to put a breakpoint. Not sure if that's really necessary or not + // (in which case it could go at the end of the function instead). + // Note issue 28603. + init.Append(ir.NewInlineMarkStmt(call.Pos().WithIsStmt(), int64(r.inlTreeIndex))) + + nparams := len(r.curfn.Dcl) + + oldcurfn := ir.CurFunc + ir.CurFunc = r.curfn + + r.curfn.Body = r.stmts() + r.curfn.Endlineno = r.pos() + + typecheck.Stmts(r.curfn.Body) + deadcode.Func(r.curfn) + + // Replace any "return" statements within the function body. + { + var edit func(ir.Node) ir.Node + edit = func(n ir.Node) ir.Node { + if ret, ok := n.(*ir.ReturnStmt); ok { + n = typecheck.Stmt(r.inlReturn(ret)) + } + ir.EditChildren(n, edit) + return n + } + edit(r.curfn) + } + + ir.CurFunc = oldcurfn + + body := ir.Nodes(r.curfn.Body) + + // Quirk: If deadcode elimination turned a non-empty function into + // an empty one, we need to set the position for the empty block + // left behind to the the inlined position for src.NoXPos, so that + // an empty string gets added into the DWARF file name listing at + // the appropriate index. + if quirksMode() && len(body) == 1 { + if block, ok := body[0].(*ir.BlockStmt); ok && len(block.List) == 0 { + block.SetPos(r.updatePos(src.NoXPos)) + } + } + + // Quirkish: We need to eagerly prune variables added during + // inlining, but removed by deadcode.FuncBody above. Unused + // variables will get removed during stack frame layout anyway, but + // len(fn.Dcl) ends up influencing things like autotmp naming. + + used := usedLocals(body) + + for i, name := range r.curfn.Dcl { + if i < nparams || used.Has(name) { + name.Curfn = callerfn + callerfn.Dcl = append(callerfn.Dcl, name) + + // Quirkish. TODO(mdempsky): Document why. + if name.AutoTemp() { + name.SetEsc(ir.EscUnknown) + + if base.Flag.GenDwarfInl != 0 { + name.SetInlLocal(true) + } else { + name.SetPos(r.inlCall.Pos()) + } + } + } + } + + body.Append(ir.NewLabelStmt(call.Pos(), r.retlabel)) + + res := ir.NewInlinedCallExpr(call.Pos(), body, append([]ir.Node(nil), r.retvars...)) + res.SetInit(init) + res.SetType(call.Type()) + res.SetTypecheck(1) + + // Inlining shouldn't add any functions to todoBodies. + assert(len(todoBodies) == 0) + + return res +} + +// inlReturn returns a statement that can substitute for the given +// return statement when inlining. +func (r *reader) inlReturn(ret *ir.ReturnStmt) *ir.BlockStmt { + pos := r.inlCall.Pos() + + block := ir.TakeInit(ret) + + if results := ret.Results; len(results) != 0 { + assert(len(r.retvars) == len(results)) + + as2 := ir.NewAssignListStmt(pos, ir.OAS2, append([]ir.Node(nil), r.retvars...), ret.Results) + + if r.delayResults { + for _, name := range r.retvars { + // TODO(mdempsky): Use inlined position of name.Pos() instead? + name := name.(*ir.Name) + block.Append(ir.NewDecl(pos, ir.ODCL, name)) + name.Defn = as2 + } + } + + block.Append(as2) + } + + block.Append(ir.NewBranchStmt(pos, ir.OGOTO, r.retlabel)) + return ir.NewBlockStmt(pos, block) +} + +// expandInline reads in an extra copy of IR to populate +// fn.Inl.{Dcl,Body}. +func expandInline(fn *ir.Func, pri pkgReaderIndex) { + // TODO(mdempsky): Remove this function. It's currently needed for + // dwarfgen for some reason, but we should be able to provide it + // with the same information some other way. + + fndcls := len(fn.Dcl) + topdcls := len(typecheck.Target.Decls) + + tmpfn := ir.NewFunc(fn.Pos()) + tmpfn.Nname = ir.NewNameAt(fn.Nname.Pos(), fn.Sym()) + tmpfn.ClosureVars = fn.ClosureVars + + { + r := pri.asReader(relocBody, syncFuncBody) + r.setType(tmpfn.Nname, fn.Type()) + + // Don't change parameter's Sym/Nname fields. + r.funarghack = true + + r.funcBody(tmpfn) + } + + oldcurfn := ir.CurFunc + ir.CurFunc = tmpfn + + typecheck.Stmts(tmpfn.Body) + deadcode.Func(tmpfn) + + ir.CurFunc = oldcurfn + + used := usedLocals(tmpfn.Body) + + for _, name := range tmpfn.Dcl { + if name.Class != ir.PAUTO || used.Has(name) { + name.Curfn = fn + fn.Inl.Dcl = append(fn.Inl.Dcl, name) + } + } + fn.Inl.Body = tmpfn.Body + + // Double check that we didn't change fn.Dcl by accident. + assert(fndcls == len(fn.Dcl)) + + // typecheck.Stmts may have added function literals to + // typecheck.Target.Decls. Remove them again so we don't risk trying + // to compile them multiple times. + typecheck.Target.Decls = typecheck.Target.Decls[:topdcls] +} + +// usedLocals returns a set of local variables that are used within body. +func usedLocals(body []ir.Node) ir.NameSet { + var used ir.NameSet + ir.VisitList(body, func(n ir.Node) { + if n, ok := n.(*ir.Name); ok && n.Op() == ir.ONAME && n.Class == ir.PAUTO { + used.Add(n) + } + }) + return used +} diff --git a/src/cmd/compile/internal/noder/reader2.go b/src/cmd/compile/internal/noder/reader2.go new file mode 100644 index 0000000000..174bd3f5bd --- /dev/null +++ b/src/cmd/compile/internal/noder/reader2.go @@ -0,0 +1,463 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "go/constant" + + "cmd/compile/internal/base" + "cmd/compile/internal/syntax" + "cmd/compile/internal/types2" + "cmd/internal/src" +) + +type pkgReader2 struct { + pkgDecoder + + check *types2.Checker + imports map[string]*types2.Package + + posBases []*syntax.PosBase + pkgs []*types2.Package + typs []types2.Type +} + +func readPackage2(check *types2.Checker, imports map[string]*types2.Package, input pkgDecoder) *types2.Package { + pr := pkgReader2{ + pkgDecoder: input, + + check: check, + imports: imports, + + posBases: make([]*syntax.PosBase, input.numElems(relocPosBase)), + pkgs: make([]*types2.Package, input.numElems(relocPkg)), + typs: make([]types2.Type, input.numElems(relocType)), + } + + r := pr.newReader(relocMeta, publicRootIdx, syncPublic) + pkg := r.pkg() + r.bool() // has init + + for i, n := 0, r.len(); i < n; i++ { + r.obj() + } + + r.sync(syncEOF) + + pkg.MarkComplete() + return pkg +} + +type reader2 struct { + decoder + + p *pkgReader2 + + tparams []*types2.TypeName +} + +func (pr *pkgReader2) newReader(k reloc, idx int, marker syncMarker) *reader2 { + return &reader2{ + decoder: pr.newDecoder(k, idx, marker), + p: pr, + } +} + +// @@@ Positions + +func (r *reader2) pos() syntax.Pos { + r.sync(syncPos) + if !r.bool() { + return syntax.Pos{} + } + + // TODO(mdempsky): Delta encoding. + posBase := r.posBase() + line := r.uint() + col := r.uint() + return syntax.MakePos(posBase, line, col) +} + +func (r *reader2) posBase() *syntax.PosBase { + return r.p.posBaseIdx(r.reloc(relocPosBase)) +} + +func (pr *pkgReader2) posBaseIdx(idx int) *syntax.PosBase { + if b := pr.posBases[idx]; b != nil { + return b + } + + r := pr.newReader(relocPosBase, idx, syncPosBase) + var b *syntax.PosBase + + filename := r.string() + _ = r.string() // absolute file name + + if r.bool() { + b = syntax.NewFileBase(filename) + } else { + pos := r.pos() + line := r.uint() + col := r.uint() + b = syntax.NewLineBase(pos, filename, line, col) + } + + pr.posBases[idx] = b + return b +} + +// @@@ Packages + +func (r *reader2) pkg() *types2.Package { + r.sync(syncPkg) + return r.p.pkgIdx(r.reloc(relocPkg)) +} + +func (pr *pkgReader2) pkgIdx(idx int) *types2.Package { + // TODO(mdempsky): Consider using some non-nil pointer to indicate + // the universe scope, so we don't need to keep re-reading it. + if pkg := pr.pkgs[idx]; pkg != nil { + return pkg + } + + pkg := pr.newReader(relocPkg, idx, syncPkgDef).doPkg() + pr.pkgs[idx] = pkg + return pkg +} + +func (r *reader2) doPkg() *types2.Package { + path := r.string() + if path == "builtin" { + return nil // universe + } + if path == "" { + path = r.p.pkgPath + } + + if pkg := r.p.imports[path]; pkg != nil { + return pkg + } + + name := r.string() + height := r.len() + + pkg := types2.NewPackageHeight(path, name, height) + r.p.imports[path] = pkg + + // TODO(mdempsky): The list of imported packages is important for + // go/types, but we could probably skip populating it for types2. + imports := make([]*types2.Package, r.len()) + for i := range imports { + imports[i] = r.pkg() + } + pkg.SetImports(imports) + + return pkg +} + +// @@@ Types + +func (r *reader2) typ() types2.Type { + r.sync(syncType) + return r.p.typIdx(r.reloc(relocType), r.tparams) +} + +func (pr *pkgReader2) typIdx(idx int, tparams []*types2.TypeName) types2.Type { + if typ := pr.typs[idx]; typ != nil { + return typ + } + + r := pr.newReader(relocType, idx, syncTypeIdx) + r.tparams = tparams + typ := r.doTyp() + assert(typ != nil) + + if pr.typs[idx] != nil { + // See comment in pkgReader.typIdx. + return pr.typs[idx] + } + + if len(tparams) == 0 { + pr.typs[idx] = typ + } + + return typ +} + +func (r *reader2) doTyp() (res types2.Type) { + switch tag := codeType(r.code(syncType)); tag { + default: + base.FatalfAt(src.NoXPos, "unhandled type tag: %v", tag) + panic("unreachable") + + case typeBasic: + return types2.Typ[r.len()] + + case typeNamed: + obj, targs := r.obj() + name := obj.(*types2.TypeName) + if len(targs) != 0 { + return r.p.check.InstantiateLazy(syntax.Pos{}, name.Type(), targs) + } + return name.Type() + + case typeTypeParam: + idx := r.len() + return r.tparams[idx].Type().(*types2.TypeParam) + + case typeArray: + len := int64(r.uint64()) + return types2.NewArray(r.typ(), len) + case typeChan: + dir := types2.ChanDir(r.len()) + return types2.NewChan(dir, r.typ()) + case typeMap: + return types2.NewMap(r.typ(), r.typ()) + case typePointer: + return types2.NewPointer(r.typ()) + case typeSignature: + return r.signature(nil) + case typeSlice: + return types2.NewSlice(r.typ()) + case typeStruct: + return r.structType() + case typeInterface: + return r.interfaceType() + case typeUnion: + return r.unionType() + } +} + +func (r *reader2) structType() *types2.Struct { + fields := make([]*types2.Var, r.len()) + var tags []string + for i := range fields { + pos := r.pos() + pkg, name := r.selector() + ftyp := r.typ() + tag := r.string() + embedded := r.bool() + + fields[i] = types2.NewField(pos, pkg, name, ftyp, embedded) + if tag != "" { + for len(tags) < i { + tags = append(tags, "") + } + tags = append(tags, tag) + } + } + return types2.NewStruct(fields, tags) +} + +func (r *reader2) unionType() *types2.Union { + terms := make([]types2.Type, r.len()) + tildes := make([]bool, len(terms)) + for i := range terms { + terms[i] = r.typ() + tildes[i] = r.bool() + } + return types2.NewUnion(terms, tildes) +} + +func (r *reader2) interfaceType() *types2.Interface { + methods := make([]*types2.Func, r.len()) + embeddeds := make([]types2.Type, r.len()) + + for i := range methods { + pos := r.pos() + pkg, name := r.selector() + mtyp := r.signature(nil) + methods[i] = types2.NewFunc(pos, pkg, name, mtyp) + } + + for i := range embeddeds { + embeddeds[i] = r.typ() + } + + typ := types2.NewInterfaceType(methods, embeddeds) + typ.Complete() + return typ +} + +func (r *reader2) signature(recv *types2.Var) *types2.Signature { + r.sync(syncSignature) + + params := r.params() + results := r.params() + variadic := r.bool() + + return types2.NewSignature(recv, params, results, variadic) +} + +func (r *reader2) params() *types2.Tuple { + r.sync(syncParams) + params := make([]*types2.Var, r.len()) + for i := range params { + params[i] = r.param() + } + return types2.NewTuple(params...) +} + +func (r *reader2) param() *types2.Var { + r.sync(syncParam) + + pos := r.pos() + pkg, name := r.localIdent() + typ := r.typ() + + return types2.NewParam(pos, pkg, name, typ) +} + +// @@@ Objects + +func (r *reader2) obj() (types2.Object, []types2.Type) { + r.sync(syncObject) + + pkg, name := r.p.objIdx(r.reloc(relocObj)) + obj := pkg.Scope().Lookup(name) + + targs := make([]types2.Type, r.len()) + for i := range targs { + targs[i] = r.typ() + } + + return obj, targs +} + +func (pr *pkgReader2) objIdx(idx int) (*types2.Package, string) { + r := pr.newReader(relocObj, idx, syncObject1) + objPkg, objName := r.qualifiedIdent() + assert(objName != "") + + bounds := r.typeParamBounds() + tag := codeObj(r.code(syncCodeObj)) + + if tag == objStub { + assert(objPkg == nil) + return objPkg, objName + } + + objPkg.Scope().InsertLazy(objName, func() types2.Object { + switch tag { + default: + panic("weird") + + case objAlias: + pos := r.pos() + typ := r.typ() + return types2.NewTypeName(pos, objPkg, objName, typ) + + case objConst: + pos := r.pos() + typ, val := r.value() + return types2.NewConst(pos, objPkg, objName, typ, val) + + case objFunc: + pos := r.pos() + r.typeParamNames(bounds) + sig := r.signature(nil) + if len(r.tparams) != 0 { + sig.SetTParams(r.tparams) + } + return types2.NewFunc(pos, objPkg, objName, sig) + + case objType: + pos := r.pos() + + return types2.NewTypeNameLazy(pos, objPkg, objName, func(named *types2.Named) (tparams []*types2.TypeName, underlying types2.Type, methods []*types2.Func) { + r.typeParamNames(bounds) + if len(r.tparams) != 0 { + tparams = r.tparams + } + + // TODO(mdempsky): Rewrite receiver types to underlying is an + // Interface? The go/types importer does this (I think because + // unit tests expected that), but cmd/compile doesn't care + // about it, so maybe we can avoid worrying about that here. + underlying = r.typ().Underlying() + + methods = make([]*types2.Func, r.len()) + for i := range methods { + methods[i] = r.method(bounds) + } + + return + }) + + case objVar: + pos := r.pos() + typ := r.typ() + return types2.NewVar(pos, objPkg, objName, typ) + } + }) + + return objPkg, objName +} + +func (r *reader2) value() (types2.Type, constant.Value) { + r.sync(syncValue) + return r.typ(), r.rawValue() +} + +func (r *reader2) typeParamBounds() []int { + r.sync(syncTypeParamBounds) + + // exported types never have implicit type parameters + // TODO(mdempsky): Hide this from public importer. + assert(r.len() == 0) + + bounds := make([]int, r.len()) + for i := range bounds { + r.sync(syncType) + bounds[i] = r.reloc(relocType) + } + return bounds +} + +func (r *reader2) typeParamNames(bounds []int) { + r.sync(syncTypeParamNames) + + r.tparams = make([]*types2.TypeName, len(bounds)) + + for i := range r.tparams { + pos := r.pos() + pkg, name := r.localIdent() + + obj := types2.NewTypeName(pos, pkg, name, nil) + r.p.check.NewTypeParam(obj, i, nil) + r.tparams[i] = obj + } + + for i, tparam := range r.tparams { + bound := r.p.typIdx(bounds[i], r.tparams) + tparam.Type().(*types2.TypeParam).SetBound(bound) + } +} + +func (r *reader2) method(bounds []int) *types2.Func { + r.sync(syncMethod) + pos := r.pos() + pkg, name := r.selector() + + r.typeParamNames(bounds) + sig := r.signature(r.param()) + if len(r.tparams) != 0 { + sig.SetRParams(r.tparams) + } + + _ = r.pos() // TODO(mdempsky): Remove; this is a hacker for linker.go. + return types2.NewFunc(pos, pkg, name, sig) +} + +func (r *reader2) qualifiedIdent() (*types2.Package, string) { return r.ident(syncSym) } +func (r *reader2) localIdent() (*types2.Package, string) { return r.ident(syncLocalIdent) } +func (r *reader2) selector() (*types2.Package, string) { return r.ident(syncSelector) } + +func (r *reader2) ident(marker syncMarker) (*types2.Package, string) { + r.sync(marker) + return r.pkg(), r.string() +} diff --git a/src/cmd/compile/internal/noder/reloc.go b/src/cmd/compile/internal/noder/reloc.go new file mode 100644 index 0000000000..961de49419 --- /dev/null +++ b/src/cmd/compile/internal/noder/reloc.go @@ -0,0 +1,40 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +// A reloc indicates a particular section within a unified IR export. +// +// TODO(mdempsky): Rename to "section" or something similar? +type reloc int + +// A relocEnt (relocation entry) is an entry in an atom's local +// reference table. +// +// TODO(mdempsky): Rename this too. +type relocEnt struct { + kind reloc + idx int +} + +// Reserved indices within the meta relocation section. +const ( + publicRootIdx = 0 + privateRootIdx = 1 +) + +const ( + relocString reloc = iota + relocMeta + relocPosBase + relocPkg + relocType + relocObj + relocObjExt + relocBody + + numRelocs = iota +) diff --git a/src/cmd/compile/internal/noder/sync.go b/src/cmd/compile/internal/noder/sync.go new file mode 100644 index 0000000000..d77a784479 --- /dev/null +++ b/src/cmd/compile/internal/noder/sync.go @@ -0,0 +1,154 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +const debug = true + +type syncMarker int + +//go:generate stringer -type=syncMarker -trimprefix=sync + +// TODO(mdempsky): Cleanup unneeded sync markers. + +// TODO(mdempsky): Split these markers into public/stable markers, and +// private ones. Also, trim unused ones. +const ( + _ syncMarker = iota + syncNode + syncBool + syncInt64 + syncUint64 + syncString + syncPos + syncPkg + syncSym + syncSelector + syncKind + syncType + syncTypePkg + syncSignature + syncParam + syncOp + syncObject + syncExpr + syncStmt + syncDecl + syncConstDecl + syncFuncDecl + syncTypeDecl + syncVarDecl + syncPragma + syncValue + syncEOF + syncMethod + syncFuncBody + syncUse + syncUseObj + syncObjectIdx + syncTypeIdx + syncBOF + syncEntry + syncOpenScope + syncCloseScope + syncGlobal + syncLocal + syncDefine + syncDefLocal + syncUseLocal + syncDefGlobal + syncUseGlobal + syncTypeParams + syncUseLabel + syncDefLabel + syncFuncLit + syncCommonFunc + syncBodyRef + syncLinksymExt + syncHack + syncSetlineno + syncName + syncImportDecl + syncDeclNames + syncDeclName + syncExprList + syncExprs + syncWrapname + syncTypeExpr + syncTypeExprOrNil + syncChanDir + syncParams + syncCloseAnotherScope + syncSum + syncUnOp + syncBinOp + syncStructType + syncInterfaceType + syncPackname + syncEmbedded + syncStmts + syncStmtsFall + syncStmtFall + syncBlockStmt + syncIfStmt + syncForStmt + syncSwitchStmt + syncRangeStmt + syncCaseClause + syncCommClause + syncSelectStmt + syncDecls + syncLabeledStmt + syncCompLit + + sync1 + sync2 + sync3 + sync4 + + syncN + syncDefImplicit + syncUseName + syncUseObjLocal + syncAddLocal + syncBothSignature + syncSetUnderlying + syncLinkname + syncStmt1 + syncStmtsEnd + syncDeclare + syncTopDecls + syncTopConstDecl + syncTopFuncDecl + syncTopTypeDecl + syncTopVarDecl + syncObject1 + syncAddBody + syncLabel + syncFuncExt + syncMethExt + syncOptLabel + syncScalar + syncStmtDecls + syncDeclLocal + syncObjLocal + syncObjLocal1 + syncDeclareLocal + syncPublic + syncPrivate + syncRelocs + syncReloc + syncUseReloc + syncVarExt + syncPkgDef + syncTypeExt + syncVal + syncCodeObj + syncPosBase + syncLocalIdent + syncTypeParamNames + syncTypeParamBounds +) diff --git a/src/cmd/compile/internal/noder/syncmarker_string.go b/src/cmd/compile/internal/noder/syncmarker_string.go new file mode 100644 index 0000000000..3eb88fb911 --- /dev/null +++ b/src/cmd/compile/internal/noder/syncmarker_string.go @@ -0,0 +1,152 @@ +// Code generated by "stringer -type=syncMarker -trimprefix=sync"; DO NOT EDIT. + +package noder + +import "strconv" + +func _() { + // An "invalid array index" compiler error signifies that the constant values have changed. + // Re-run the stringer command to generate them again. + var x [1]struct{} + _ = x[syncNode-1] + _ = x[syncBool-2] + _ = x[syncInt64-3] + _ = x[syncUint64-4] + _ = x[syncString-5] + _ = x[syncPos-6] + _ = x[syncPkg-7] + _ = x[syncSym-8] + _ = x[syncSelector-9] + _ = x[syncKind-10] + _ = x[syncType-11] + _ = x[syncTypePkg-12] + _ = x[syncSignature-13] + _ = x[syncParam-14] + _ = x[syncOp-15] + _ = x[syncObject-16] + _ = x[syncExpr-17] + _ = x[syncStmt-18] + _ = x[syncDecl-19] + _ = x[syncConstDecl-20] + _ = x[syncFuncDecl-21] + _ = x[syncTypeDecl-22] + _ = x[syncVarDecl-23] + _ = x[syncPragma-24] + _ = x[syncValue-25] + _ = x[syncEOF-26] + _ = x[syncMethod-27] + _ = x[syncFuncBody-28] + _ = x[syncUse-29] + _ = x[syncUseObj-30] + _ = x[syncObjectIdx-31] + _ = x[syncTypeIdx-32] + _ = x[syncBOF-33] + _ = x[syncEntry-34] + _ = x[syncOpenScope-35] + _ = x[syncCloseScope-36] + _ = x[syncGlobal-37] + _ = x[syncLocal-38] + _ = x[syncDefine-39] + _ = x[syncDefLocal-40] + _ = x[syncUseLocal-41] + _ = x[syncDefGlobal-42] + _ = x[syncUseGlobal-43] + _ = x[syncTypeParams-44] + _ = x[syncUseLabel-45] + _ = x[syncDefLabel-46] + _ = x[syncFuncLit-47] + _ = x[syncCommonFunc-48] + _ = x[syncBodyRef-49] + _ = x[syncLinksymExt-50] + _ = x[syncHack-51] + _ = x[syncSetlineno-52] + _ = x[syncName-53] + _ = x[syncImportDecl-54] + _ = x[syncDeclNames-55] + _ = x[syncDeclName-56] + _ = x[syncExprList-57] + _ = x[syncExprs-58] + _ = x[syncWrapname-59] + _ = x[syncTypeExpr-60] + _ = x[syncTypeExprOrNil-61] + _ = x[syncChanDir-62] + _ = x[syncParams-63] + _ = x[syncCloseAnotherScope-64] + _ = x[syncSum-65] + _ = x[syncUnOp-66] + _ = x[syncBinOp-67] + _ = x[syncStructType-68] + _ = x[syncInterfaceType-69] + _ = x[syncPackname-70] + _ = x[syncEmbedded-71] + _ = x[syncStmts-72] + _ = x[syncStmtsFall-73] + _ = x[syncStmtFall-74] + _ = x[syncBlockStmt-75] + _ = x[syncIfStmt-76] + _ = x[syncForStmt-77] + _ = x[syncSwitchStmt-78] + _ = x[syncRangeStmt-79] + _ = x[syncCaseClause-80] + _ = x[syncCommClause-81] + _ = x[syncSelectStmt-82] + _ = x[syncDecls-83] + _ = x[syncLabeledStmt-84] + _ = x[syncCompLit-85] + _ = x[sync1-86] + _ = x[sync2-87] + _ = x[sync3-88] + _ = x[sync4-89] + _ = x[syncN-90] + _ = x[syncDefImplicit-91] + _ = x[syncUseName-92] + _ = x[syncUseObjLocal-93] + _ = x[syncAddLocal-94] + _ = x[syncBothSignature-95] + _ = x[syncSetUnderlying-96] + _ = x[syncLinkname-97] + _ = x[syncStmt1-98] + _ = x[syncStmtsEnd-99] + _ = x[syncDeclare-100] + _ = x[syncTopDecls-101] + _ = x[syncTopConstDecl-102] + _ = x[syncTopFuncDecl-103] + _ = x[syncTopTypeDecl-104] + _ = x[syncTopVarDecl-105] + _ = x[syncObject1-106] + _ = x[syncAddBody-107] + _ = x[syncLabel-108] + _ = x[syncFuncExt-109] + _ = x[syncMethExt-110] + _ = x[syncOptLabel-111] + _ = x[syncScalar-112] + _ = x[syncStmtDecls-113] + _ = x[syncDeclLocal-114] + _ = x[syncObjLocal-115] + _ = x[syncObjLocal1-116] + _ = x[syncDeclareLocal-117] + _ = x[syncPublic-118] + _ = x[syncPrivate-119] + _ = x[syncRelocs-120] + _ = x[syncReloc-121] + _ = x[syncUseReloc-122] + _ = x[syncVarExt-123] + _ = x[syncPkgDef-124] + _ = x[syncTypeExt-125] + _ = x[syncVal-126] + _ = x[syncCodeObj-127] + _ = x[syncPosBase-128] + _ = x[syncLocalIdent-129] +} + +const _syncMarker_name = "NodeBoolInt64Uint64StringPosPkgSymSelectorKindTypeTypePkgSignatureParamOpObjectExprStmtDeclConstDeclFuncDeclTypeDeclVarDeclPragmaValueEOFMethodFuncBodyUseUseObjObjectIdxTypeIdxBOFEntryOpenScopeCloseScopeGlobalLocalDefineDefLocalUseLocalDefGlobalUseGlobalTypeParamsUseLabelDefLabelFuncLitCommonFuncBodyRefLinksymExtHackSetlinenoNameImportDeclDeclNamesDeclNameExprListExprsWrapnameTypeExprTypeExprOrNilChanDirParamsCloseAnotherScopeSumUnOpBinOpStructTypeInterfaceTypePacknameEmbeddedStmtsStmtsFallStmtFallBlockStmtIfStmtForStmtSwitchStmtRangeStmtCaseClauseCommClauseSelectStmtDeclsLabeledStmtCompLit1234NDefImplicitUseNameUseObjLocalAddLocalBothSignatureSetUnderlyingLinknameStmt1StmtsEndDeclareTopDeclsTopConstDeclTopFuncDeclTopTypeDeclTopVarDeclObject1AddBodyLabelFuncExtMethExtOptLabelScalarStmtDeclsDeclLocalObjLocalObjLocal1DeclareLocalPublicPrivateRelocsRelocUseRelocVarExtPkgDefTypeExtValCodeObjPosBaseLocalIdent" + +var _syncMarker_index = [...]uint16{0, 4, 8, 13, 19, 25, 28, 31, 34, 42, 46, 50, 57, 66, 71, 73, 79, 83, 87, 91, 100, 108, 116, 123, 129, 134, 137, 143, 151, 154, 160, 169, 176, 179, 184, 193, 203, 209, 214, 220, 228, 236, 245, 254, 264, 272, 280, 287, 297, 304, 314, 318, 327, 331, 341, 350, 358, 366, 371, 379, 387, 400, 407, 413, 430, 433, 437, 442, 452, 465, 473, 481, 486, 495, 503, 512, 518, 525, 535, 544, 554, 564, 574, 579, 590, 597, 598, 599, 600, 601, 602, 613, 620, 631, 639, 652, 665, 673, 678, 686, 693, 701, 713, 724, 735, 745, 752, 759, 764, 771, 778, 786, 792, 801, 810, 818, 827, 839, 845, 852, 858, 863, 871, 877, 883, 890, 893, 900, 907, 917} + +func (i syncMarker) String() string { + i -= 1 + if i < 0 || i >= syncMarker(len(_syncMarker_index)-1) { + return "syncMarker(" + strconv.FormatInt(int64(i+1), 10) + ")" + } + return _syncMarker_name[_syncMarker_index[i]:_syncMarker_index[i+1]] +} diff --git a/src/cmd/compile/internal/noder/unified.go b/src/cmd/compile/internal/noder/unified.go new file mode 100644 index 0000000000..9a41ea9dfe --- /dev/null +++ b/src/cmd/compile/internal/noder/unified.go @@ -0,0 +1,276 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "bytes" + "fmt" + "internal/goversion" + "io" + "runtime" + "sort" + + "cmd/compile/internal/base" + "cmd/compile/internal/inline" + "cmd/compile/internal/ir" + "cmd/compile/internal/typecheck" + "cmd/compile/internal/types" + "cmd/compile/internal/types2" + "cmd/internal/src" +) + +// localPkgReader holds the package reader used for reading the local +// package. It exists so the unified IR linker can refer back to it +// later. +var localPkgReader *pkgReader + +// useUnifiedIR reports whether the unified IR frontend should be +// used; and if so, uses it to construct the local package's IR. +func useUnifiedIR(noders []*noder) { + inline.NewInline = InlineCall + + if !quirksMode() { + writeNewExportFunc = writeNewExport + } + + newReadImportFunc = func(data string, pkg1 *types.Pkg, check *types2.Checker, packages map[string]*types2.Package) (pkg2 *types2.Package, err error) { + pr := newPkgDecoder(pkg1.Path, data) + + // Read package descriptors for both types2 and compiler backend. + readPackage(newPkgReader(pr), pkg1) + pkg2 = readPackage2(check, packages, pr) + return + } + + data := writePkgStub(noders) + + // We already passed base.Flag.Lang to types2 to handle validating + // the user's source code. Bump it up now to the current version and + // re-parse, so typecheck doesn't complain if we construct IR that + // utilizes newer Go features. + base.Flag.Lang = fmt.Sprintf("go1.%d", goversion.Version) + types.ParseLangFlag() + + assert(types.LocalPkg.Path == "") + types.LocalPkg.Height = 0 // reset so pkgReader.pkgIdx doesn't complain + target := typecheck.Target + + typecheck.TypecheckAllowed = true + + localPkgReader = newPkgReader(newPkgDecoder(types.LocalPkg.Path, data)) + readPackage(localPkgReader, types.LocalPkg) + + r := localPkgReader.newReader(relocMeta, privateRootIdx, syncPrivate) + r.ext = r + r.pkgInit(types.LocalPkg, target) + + // Don't use range--bodyIdx can add closures to todoBodies. + for len(todoBodies) > 0 { + // The order we expand bodies doesn't matter, so pop from the end + // to reduce todoBodies reallocations if it grows further. + fn := todoBodies[len(todoBodies)-1] + todoBodies = todoBodies[:len(todoBodies)-1] + + pri, ok := bodyReader[fn] + assert(ok) + pri.funcBody(fn) + + // Instantiated generic function: add to Decls for typechecking + // and compilation. + if len(pri.implicits) != 0 && fn.OClosure == nil { + target.Decls = append(target.Decls, fn) + } + } + todoBodies = nil + + // Don't use range--typecheck can add closures to Target.Decls. + for i := 0; i < len(target.Decls); i++ { + target.Decls[i] = typecheck.Stmt(target.Decls[i]) + } + + // Don't use range--typecheck can add closures to Target.Decls. + for i := 0; i < len(target.Decls); i++ { + if fn, ok := target.Decls[i].(*ir.Func); ok { + if base.Flag.W > 1 { + s := fmt.Sprintf("\nbefore typecheck %v", fn) + ir.Dump(s, fn) + } + ir.CurFunc = fn + typecheck.Stmts(fn.Body) + if base.Flag.W > 1 { + s := fmt.Sprintf("\nafter typecheck %v", fn) + ir.Dump(s, fn) + } + } + } + + base.ExitIfErrors() // just in case +} + +// writePkgStub type checks the given parsed source files and then +// returns +func writePkgStub(noders []*noder) string { + m, pkg, info := checkFiles(noders) + + pw := newPkgWriter(m, pkg, info) + + pw.collectDecls(noders) + + publicRootWriter := pw.newWriter(relocMeta, syncPublic) + privateRootWriter := pw.newWriter(relocMeta, syncPrivate) + + assert(publicRootWriter.idx == publicRootIdx) + assert(privateRootWriter.idx == privateRootIdx) + + { + w := publicRootWriter + w.pkg(pkg) + w.bool(false) // has init; XXX + + scope := pkg.Scope() + names := scope.Names() + w.len(len(names)) + for _, name := range scope.Names() { + w.obj(scope.Lookup(name), nil) + } + + w.sync(syncEOF) + w.flush() + } + + { + w := privateRootWriter + w.ext = w + w.pkgInit(noders) + w.flush() + } + + var sb bytes.Buffer // TODO(mdempsky): strings.Builder after #44505 is resolved + pw.dump(&sb) + + // At this point, we're done with types2. Make sure the package is + // garbage collected. + freePackage(pkg) + + return sb.String() +} + +// freePackage ensures the given package is garbage collected. +func freePackage(pkg *types2.Package) { + // Set a finalizer on pkg so we can detect if/when it's collected. + done := make(chan struct{}) + runtime.SetFinalizer(pkg, func(*types2.Package) { close(done) }) + + // Important: objects involved in cycles are not finalized, so zero + // out pkg to break its cycles and allow the finalizer to run. + *pkg = types2.Package{} + + // It typically takes just 1 or 2 cycles to release pkg, but it + // doesn't hurt to try a few more times. + for i := 0; i < 10; i++ { + select { + case <-done: + return + default: + runtime.GC() + } + } + + base.Fatalf("package never finalized") +} + +func readPackage(pr *pkgReader, importpkg *types.Pkg) { + r := pr.newReader(relocMeta, publicRootIdx, syncPublic) + + pkg := r.pkg() + assert(pkg == importpkg) + + if r.bool() { + sym := pkg.Lookup(".inittask") + task := ir.NewNameAt(src.NoXPos, sym) + task.Class = ir.PEXTERN + sym.Def = task + } + + for i, n := 0, r.len(); i < n; i++ { + r.sync(syncObject) + idx := r.reloc(relocObj) + assert(r.len() == 0) + + path, name, code, _ := r.p.peekObj(idx) + if code != objStub { + objReader[types.NewPkg(path, "").Lookup(name)] = pkgReaderIndex{pr, idx, nil} + } + } +} + +func writeNewExport(out io.Writer) { + l := linker{ + pw: newPkgEncoder(), + + pkgs: make(map[string]int), + decls: make(map[*types.Sym]int), + } + + publicRootWriter := l.pw.newEncoder(relocMeta, syncPublic) + assert(publicRootWriter.idx == publicRootIdx) + + var selfPkgIdx int + + { + pr := localPkgReader + r := pr.newDecoder(relocMeta, publicRootIdx, syncPublic) + + r.sync(syncPkg) + selfPkgIdx = l.relocIdx(pr, relocPkg, r.reloc(relocPkg)) + + r.bool() // has init + + for i, n := 0, r.len(); i < n; i++ { + r.sync(syncObject) + idx := r.reloc(relocObj) + assert(r.len() == 0) + + xpath, xname, xtag, _ := pr.peekObj(idx) + assert(xpath == pr.pkgPath) + assert(xtag != objStub) + + if types.IsExported(xname) { + l.relocIdx(pr, relocObj, idx) + } + } + + r.sync(syncEOF) + } + + { + var idxs []int + for _, idx := range l.decls { + idxs = append(idxs, idx) + } + sort.Ints(idxs) + + w := publicRootWriter + + w.sync(syncPkg) + w.reloc(relocPkg, selfPkgIdx) + + w.bool(typecheck.Lookup(".inittask").Def != nil) + + w.len(len(idxs)) + for _, idx := range idxs { + w.sync(syncObject) + w.reloc(relocObj, idx) + w.len(0) + } + + w.sync(syncEOF) + w.flush() + } + + l.pw.dump(out) +} diff --git a/src/cmd/compile/internal/noder/writer.go b/src/cmd/compile/internal/noder/writer.go new file mode 100644 index 0000000000..b39dd8651b --- /dev/null +++ b/src/cmd/compile/internal/noder/writer.go @@ -0,0 +1,1746 @@ +// UNREVIEWED + +// Copyright 2021 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package noder + +import ( + "fmt" + "go/constant" + + "cmd/compile/internal/base" + "cmd/compile/internal/ir" + "cmd/compile/internal/syntax" + "cmd/compile/internal/types2" +) + +type pkgWriter struct { + pkgEncoder + + m posMap + curpkg *types2.Package + info *types2.Info + + posBasesIdx map[*syntax.PosBase]int + pkgsIdx map[*types2.Package]int + typsIdx map[types2.Type]int + globalsIdx map[types2.Object]int + + funDecls map[*types2.Func]*syntax.FuncDecl + typDecls map[*types2.TypeName]typeDeclGen + + linknames map[types2.Object]string + cgoPragmas [][]string + + dups dupTypes +} + +func newPkgWriter(m posMap, pkg *types2.Package, info *types2.Info) *pkgWriter { + return &pkgWriter{ + pkgEncoder: newPkgEncoder(), + + m: m, + curpkg: pkg, + info: info, + + pkgsIdx: make(map[*types2.Package]int), + globalsIdx: make(map[types2.Object]int), + typsIdx: make(map[types2.Type]int), + + posBasesIdx: make(map[*syntax.PosBase]int), + + funDecls: make(map[*types2.Func]*syntax.FuncDecl), + typDecls: make(map[*types2.TypeName]typeDeclGen), + + linknames: make(map[types2.Object]string), + } +} + +func (pw *pkgWriter) errorf(p poser, msg string, args ...interface{}) { + base.ErrorfAt(pw.m.pos(p), msg, args...) +} + +func (pw *pkgWriter) fatalf(p poser, msg string, args ...interface{}) { + base.FatalfAt(pw.m.pos(p), msg, args...) +} + +func (pw *pkgWriter) unexpected(what string, p poser) { + pw.fatalf(p, "unexpected %s: %v (%T)", what, p, p) +} + +type writer struct { + p *pkgWriter + + encoder + + // For writing out object descriptions, ext points to the extension + // writer for where we can write the compiler's private extension + // details for the object. + // + // TODO(mdempsky): This is a little hacky, but works easiest with + // the way things are currently. + ext *writer + + // TODO(mdempsky): We should be able to prune localsIdx whenever a + // scope closes, and then maybe we can just use the same map for + // storing the TypeParams too (as their TypeName instead). + + // type parameters. explicitIdx has the type parameters declared on + // the current object, while implicitIdx has the type parameters + // declared on the enclosing object (if any). + // + // TODO(mdempsky): Merge these back together, now that I've got them + // working. + implicitIdx map[*types2.TypeParam]int + explicitIdx map[*types2.TypeParam]int + + // variables declared within this function + localsIdx map[types2.Object]int +} + +func (pw *pkgWriter) newWriter(k reloc, marker syncMarker) *writer { + return &writer{ + encoder: pw.newEncoder(k, marker), + p: pw, + } +} + +// @@@ Positions + +func (w *writer) pos(p poser) { + w.sync(syncPos) + pos := p.Pos() + + // TODO(mdempsky): Track down the remaining cases here and fix them. + if !w.bool(pos.IsKnown()) { + return + } + + // TODO(mdempsky): Delta encoding. Also, if there's a b-side, update + // its position base too (but not vice versa!). + w.posBase(pos.Base()) + w.uint(pos.Line()) + w.uint(pos.Col()) +} + +func (w *writer) posBase(b *syntax.PosBase) { + w.reloc(relocPosBase, w.p.posBaseIdx(b)) +} + +func (pw *pkgWriter) posBaseIdx(b *syntax.PosBase) int { + if idx, ok := pw.posBasesIdx[b]; ok { + return idx + } + + w := pw.newWriter(relocPosBase, syncPosBase) + w.p.posBasesIdx[b] = w.idx + + // TODO(mdempsky): What exactly does "fileh" do anyway? Is writing + // out both of these strings really the right thing to do here? + fn := b.Filename() + w.string(fn) + w.string(fileh(fn)) + + if !w.bool(b.IsFileBase()) { + w.pos(b) + w.uint(b.Line()) + w.uint(b.Col()) + } + + return w.flush() +} + +// @@@ Packages + +func (w *writer) pkg(pkg *types2.Package) { + w.sync(syncPkg) + w.reloc(relocPkg, w.p.pkgIdx(pkg)) +} + +func (pw *pkgWriter) pkgIdx(pkg *types2.Package) int { + if idx, ok := pw.pkgsIdx[pkg]; ok { + return idx + } + + w := pw.newWriter(relocPkg, syncPkgDef) + pw.pkgsIdx[pkg] = w.idx + + if pkg == nil { + w.string("builtin") + } else { + var path string + if pkg != w.p.curpkg { + path = pkg.Path() + } + w.string(path) + w.string(pkg.Name()) + w.len(pkg.Height()) + + w.len(len(pkg.Imports())) + for _, imp := range pkg.Imports() { + w.pkg(imp) + } + } + + return w.flush() +} + +// @@@ Types + +func (w *writer) typ(typ types2.Type) { + w.sync(syncType) + + if quirksMode() { + typ = w.p.dups.orig(typ) + } + + w.reloc(relocType, w.p.typIdx(typ, w.implicitIdx, w.explicitIdx)) +} + +func (pw *pkgWriter) typIdx(typ types2.Type, implicitIdx, explicitIdx map[*types2.TypeParam]int) int { + if idx, ok := pw.typsIdx[typ]; ok { + return idx + } + + w := pw.newWriter(relocType, syncTypeIdx) + w.implicitIdx = implicitIdx + w.explicitIdx = explicitIdx + + pw.typsIdx[typ] = w.idx // handle cycles + w.doTyp(typ) + return w.flush() +} + +func (w *writer) doTyp(typ types2.Type) { + switch typ := typ.(type) { + default: + base.Fatalf("unexpected type: %v (%T)", typ, typ) + + case *types2.Basic: + if kind := typ.Kind(); types2.Typ[kind] == typ { + w.code(typeBasic) + w.len(int(kind)) + break + } + + // Handle "byte" and "rune" as references to their TypeName. + obj := types2.Universe.Lookup(typ.Name()) + assert(obj.Type() == typ) + + w.code(typeNamed) + w.obj(obj, nil) + + case *types2.Named: + // Type aliases can refer to uninstantiated generic types, so we + // might see len(TParams) != 0 && len(TArgs) == 0 here. + // TODO(mdempsky): Revisit after #46477 is resolved. + assert(len(typ.TParams()) == len(typ.TArgs()) || len(typ.TArgs()) == 0) + + // TODO(mdempsky): Why do we need to loop here? + orig := typ + for orig.TArgs() != nil { + orig = orig.Orig() + } + + w.code(typeNamed) + w.obj(orig.Obj(), typ.TArgs()) + + case *types2.TypeParam: + w.code(typeTypeParam) + if idx, ok := w.implicitIdx[typ]; ok { + w.len(idx) + } else if idx, ok := w.explicitIdx[typ]; ok { + w.len(len(w.implicitIdx) + idx) + } else { + w.p.fatalf(typ.Obj(), "%v not in %v or %v", typ, w.implicitIdx, w.explicitIdx) + } + + case *types2.Array: + w.code(typeArray) + w.uint64(uint64(typ.Len())) + w.typ(typ.Elem()) + + case *types2.Chan: + w.code(typeChan) + w.len(int(typ.Dir())) + w.typ(typ.Elem()) + + case *types2.Map: + w.code(typeMap) + w.typ(typ.Key()) + w.typ(typ.Elem()) + + case *types2.Pointer: + w.code(typePointer) + w.typ(typ.Elem()) + + case *types2.Signature: + assert(typ.TParams() == nil) + w.code(typeSignature) + w.signature(typ) + + case *types2.Slice: + w.code(typeSlice) + w.typ(typ.Elem()) + + case *types2.Struct: + w.code(typeStruct) + w.structType(typ) + + case *types2.Interface: + w.code(typeInterface) + w.interfaceType(typ) + + case *types2.Union: + w.code(typeUnion) + w.unionType(typ) + } +} + +func (w *writer) structType(typ *types2.Struct) { + w.len(typ.NumFields()) + for i := 0; i < typ.NumFields(); i++ { + f := typ.Field(i) + w.pos(f) + w.selector(f) + w.typ(f.Type()) + w.string(typ.Tag(i)) + w.bool(f.Embedded()) + } +} + +func (w *writer) unionType(typ *types2.Union) { + w.len(typ.NumTerms()) + for i := 0; i < typ.NumTerms(); i++ { + term, tilde := typ.Term(i) + w.typ(term) + w.bool(tilde) + } +} + +func (w *writer) interfaceType(typ *types2.Interface) { + w.len(typ.NumExplicitMethods()) + w.len(typ.NumEmbeddeds()) + + for i := 0; i < typ.NumExplicitMethods(); i++ { + m := typ.ExplicitMethod(i) + sig := m.Type().(*types2.Signature) + assert(sig.TParams() == nil) + + w.pos(m) + w.selector(m) + w.signature(sig) + } + + for i := 0; i < typ.NumEmbeddeds(); i++ { + w.typ(typ.EmbeddedType(i)) + } +} + +func (w *writer) signature(sig *types2.Signature) { + w.sync(syncSignature) + w.params(sig.Params()) + w.params(sig.Results()) + w.bool(sig.Variadic()) +} + +func (w *writer) params(typ *types2.Tuple) { + w.sync(syncParams) + w.len(typ.Len()) + for i := 0; i < typ.Len(); i++ { + w.param(typ.At(i)) + } +} + +func (w *writer) param(param *types2.Var) { + w.sync(syncParam) + w.pos(param) + w.localIdent(param) + w.typ(param.Type()) +} + +// @@@ Objects + +func (w *writer) obj(obj types2.Object, explicits []types2.Type) { + w.sync(syncObject) + + var implicitIdx map[*types2.TypeParam]int + if isDefinedType(obj) && !isGlobal(obj) { + implicitIdx = w.implicitIdx + } + w.reloc(relocObj, w.p.objIdx(obj, implicitIdx)) + + w.len(len(explicits)) + for _, explicit := range explicits { + w.typ(explicit) + } +} + +func (pw *pkgWriter) objIdx(obj types2.Object, implicitIdx map[*types2.TypeParam]int) int { + if idx, ok := pw.globalsIdx[obj]; ok { + return idx + } + + w := pw.newWriter(relocObj, syncObject1) + w.ext = pw.newWriter(relocObjExt, syncObject1) + assert(w.ext.idx == w.idx) + + pw.globalsIdx[obj] = w.idx + + w.implicitIdx = implicitIdx + w.ext.implicitIdx = implicitIdx + + w.doObj(obj) + + w.flush() + w.ext.flush() + + return w.idx +} + +func (w *writer) doObj(obj types2.Object) { + // Ident goes first so importer can avoid unnecessary work if + // they've already resolved this object. + w.qualifiedIdent(obj) + + tparams := objTypeParams(obj) + w.setTypeParams(tparams) + w.typeParamBounds(tparams) + + if obj.Pkg() != w.p.curpkg { + w.code(objStub) + return + } + + switch obj := obj.(type) { + default: + w.p.unexpected("object", obj) + + case *types2.Const: + w.code(objConst) + w.pos(obj) + w.value(obj.Type(), obj.Val()) + + case *types2.Func: + decl, ok := w.p.funDecls[obj] + assert(ok) + sig := obj.Type().(*types2.Signature) + + // Rewrite blank methods into blank functions. + // They aren't included in the receiver type's method set, + // and we still want to write them out to be compiled + // for regression tests. + // TODO(mdempsky): Change regress tests to avoid relying + // on blank functions/methods, so we can just ignore them + // altogether. + if recv := sig.Recv(); recv != nil { + assert(obj.Name() == "_") + assert(sig.TParams() == nil) + + params := make([]*types2.Var, 1+sig.Params().Len()) + params[0] = recv + for i := 0; i < sig.Params().Len(); i++ { + params[1+i] = sig.Params().At(i) + } + sig = types2.NewSignature(nil, types2.NewTuple(params...), sig.Results(), sig.Variadic()) + } + + w.code(objFunc) + w.pos(obj) + w.typeParamNames(sig.TParams()) + w.signature(sig) + w.pos(decl) + w.ext.funcExt(obj) + + case *types2.TypeName: + decl, ok := w.p.typDecls[obj] + assert(ok) + + if obj.IsAlias() { + w.code(objAlias) + w.pos(obj) + w.typ(obj.Type()) + break + } + + named := obj.Type().(*types2.Named) + assert(named.TArgs() == nil) + + w.code(objType) + w.pos(obj) + w.typeParamNames(named.TParams()) + w.ext.typeExt(obj) + w.typExpr(decl.Type) + + w.len(named.NumMethods()) + for i := 0; i < named.NumMethods(); i++ { + w.method(named.Method(i)) + } + + case *types2.Var: + w.code(objVar) + w.pos(obj) + w.typ(obj.Type()) + w.ext.varExt(obj) + } +} + +// typExpr writes the type represented by the given expression. +func (w *writer) typExpr(expr syntax.Expr) { + tv, ok := w.p.info.Types[expr] + assert(ok) + assert(tv.IsType()) + w.typ(tv.Type) +} + +func (w *writer) value(typ types2.Type, val constant.Value) { + w.sync(syncValue) + w.typ(typ) + w.rawValue(val) +} + +func (w *writer) setTypeParams(tparams []*types2.TypeName) { + if len(tparams) == 0 { + return + } + + explicitIdx := make(map[*types2.TypeParam]int) + for _, tparam := range tparams { + explicitIdx[tparam.Type().(*types2.TypeParam)] = len(explicitIdx) + } + + w.explicitIdx = explicitIdx + w.ext.explicitIdx = explicitIdx +} + +func (w *writer) typeParamBounds(tparams []*types2.TypeName) { + w.sync(syncTypeParamBounds) + + // TODO(mdempsky): Remove. It's useful for debugging at the moment, + // but it doesn't belong here. + w.len(len(w.implicitIdx)) + w.len(len(w.explicitIdx)) + assert(len(w.explicitIdx) == len(tparams)) + + for _, tparam := range tparams { + w.typ(tparam.Type().(*types2.TypeParam).Bound()) + } +} + +func (w *writer) typeParamNames(tparams []*types2.TypeName) { + w.sync(syncTypeParamNames) + + for _, tparam := range tparams { + w.pos(tparam) + w.localIdent(tparam) + } +} + +func (w *writer) method(meth *types2.Func) { + decl, ok := w.p.funDecls[meth] + assert(ok) + sig := meth.Type().(*types2.Signature) + + assert(len(w.explicitIdx) == len(sig.RParams())) + w.setTypeParams(sig.RParams()) + + w.sync(syncMethod) + w.pos(meth) + w.selector(meth) + w.typeParamNames(sig.RParams()) + w.param(sig.Recv()) + w.signature(sig) + + w.pos(decl) // XXX: Hack to workaround linker limitations. + w.ext.funcExt(meth) +} + +// qualifiedIdent writes out the name of an object declared at package +// scope. (For now, it's also used to refer to local defined types.) +func (w *writer) qualifiedIdent(obj types2.Object) { + w.sync(syncSym) + + name := obj.Name() + if isDefinedType(obj) && !isGlobal(obj) { + // TODO(mdempsky): Find a better solution, this is terrible. + decl, ok := w.p.typDecls[obj.(*types2.TypeName)] + assert(ok) + name = fmt.Sprintf("%s·%v", name, decl.gen) + } + + w.pkg(obj.Pkg()) + w.string(name) +} + +// TODO(mdempsky): We should be able to omit pkg from both localIdent +// and selector, because they should always be known from context. +// However, past frustrations with this optimization in iexport make +// me a little nervous to try it again. + +// localIdent writes the name of a locally declared object (i.e., +// objects that can only be accessed by name, within the context of a +// particular function). +func (w *writer) localIdent(obj types2.Object) { + assert(!isGlobal(obj)) + w.sync(syncLocalIdent) + w.pkg(obj.Pkg()) + w.string(obj.Name()) +} + +// selector writes the name of a field or method (i.e., objects that +// can only be accessed using selector expressions). +func (w *writer) selector(obj types2.Object) { + w.sync(syncSelector) + w.pkg(obj.Pkg()) + w.string(obj.Name()) +} + +// @@@ Compiler extensions + +func (w *writer) funcExt(obj *types2.Func) { + decl, ok := w.p.funDecls[obj] + assert(ok) + + // TODO(mdempsky): Extend these pragma validation flags to account + // for generics. E.g., linkname probably doesn't make sense at + // least. + + pragma := asPragmaFlag(decl.Pragma) + if pragma&ir.Systemstack != 0 && pragma&ir.Nosplit != 0 { + w.p.errorf(decl, "go:nosplit and go:systemstack cannot be combined") + } + + if decl.Body != nil { + if pragma&ir.Noescape != 0 { + w.p.errorf(decl, "can only use //go:noescape with external func implementations") + } + } else { + if base.Flag.Complete || decl.Name.Value == "init" { + // Linknamed functions are allowed to have no body. Hopefully + // the linkname target has a body. See issue 23311. + if _, ok := w.p.linknames[obj]; !ok { + w.p.errorf(decl, "missing function body") + } + } + } + + w.sync(syncFuncExt) + w.pragmaFlag(pragma) + w.linkname(obj) + w.bool(false) // stub extension + w.addBody(obj.Type().(*types2.Signature), decl.Body, make(map[types2.Object]int)) + w.sync(syncEOF) +} + +func (w *writer) typeExt(obj *types2.TypeName) { + decl, ok := w.p.typDecls[obj] + assert(ok) + + w.sync(syncTypeExt) + + w.pragmaFlag(asPragmaFlag(decl.Pragma)) + + // No LSym.SymIdx info yet. + w.int64(-1) + w.int64(-1) +} + +func (w *writer) varExt(obj *types2.Var) { + w.sync(syncVarExt) + w.linkname(obj) +} + +func (w *writer) linkname(obj types2.Object) { + w.sync(syncLinkname) + w.int64(-1) + w.string(w.p.linknames[obj]) +} + +func (w *writer) pragmaFlag(p ir.PragmaFlag) { + w.sync(syncPragma) + w.int(int(p)) +} + +// @@@ Function bodies + +func (w *writer) addBody(sig *types2.Signature, block *syntax.BlockStmt, localsIdx map[types2.Object]int) { + // TODO(mdempsky): Theoretically, I think at this point we want to + // extend the implicit type parameters list with any new explicit + // type parameters. + // + // However, I believe that's moot: declared functions and methods + // have explicit type parameters, but are always declared at package + // scope (which has no implicit type parameters); and function + // literals can appear within a type-parameterized function (i.e., + // implicit type parameters), but cannot have explicit type + // parameters of their own. + // + // So I think it's safe to just use whichever is non-empty. + implicitIdx := w.implicitIdx + if len(implicitIdx) == 0 { + implicitIdx = w.explicitIdx + } else { + assert(len(w.explicitIdx) == 0) + } + + w.sync(syncAddBody) + w.reloc(relocBody, w.p.bodyIdx(w.p.curpkg, sig, block, implicitIdx, localsIdx)) +} + +func (pw *pkgWriter) bodyIdx(pkg *types2.Package, sig *types2.Signature, block *syntax.BlockStmt, implicitIdx map[*types2.TypeParam]int, localsIdx map[types2.Object]int) int { + w := pw.newWriter(relocBody, syncFuncBody) + w.implicitIdx = implicitIdx + w.localsIdx = localsIdx + + w.funcargs(sig) + if w.bool(block != nil) { + w.stmts(block.List) + w.pos(block.Rbrace) + } + + return w.flush() +} + +func (w *writer) funcargs(sig *types2.Signature) { + do := func(params *types2.Tuple, result bool) { + for i := 0; i < params.Len(); i++ { + w.funcarg(params.At(i), result) + } + } + + if recv := sig.Recv(); recv != nil { + w.funcarg(recv, false) + } + do(sig.Params(), false) + do(sig.Results(), true) +} + +func (w *writer) funcarg(param *types2.Var, result bool) { + if param.Name() != "" || result { + w.addLocal(param) + } +} + +func (w *writer) addLocal(obj types2.Object) { + w.sync(syncAddLocal) + idx := len(w.localsIdx) + if debug { + w.int(idx) + } + w.localsIdx[obj] = idx +} + +func (w *writer) useLocal(obj types2.Object) { + w.sync(syncUseObjLocal) + idx, ok := w.localsIdx[obj] + assert(ok) + w.len(idx) +} + +func (w *writer) openScope(pos syntax.Pos) { + w.sync(syncOpenScope) + w.pos(pos) +} + +func (w *writer) closeScope(pos syntax.Pos) { + w.sync(syncCloseScope) + w.pos(pos) + w.closeAnotherScope() +} + +func (w *writer) closeAnotherScope() { + w.sync(syncCloseAnotherScope) +} + +// @@@ Statements + +func (w *writer) stmt(stmt syntax.Stmt) { + var stmts []syntax.Stmt + if stmt != nil { + stmts = []syntax.Stmt{stmt} + } + w.stmts(stmts) +} + +func (w *writer) stmts(stmts []syntax.Stmt) { + w.sync(syncStmts) + for _, stmt := range stmts { + w.stmt1(stmt) + } + w.code(stmtEnd) + w.sync(syncStmtsEnd) +} + +func (w *writer) stmt1(stmt syntax.Stmt) { + switch stmt := stmt.(type) { + default: + w.p.unexpected("statement", stmt) + + case nil, *syntax.EmptyStmt: + return + + case *syntax.AssignStmt: + switch { + case stmt.Rhs == nil: + w.code(stmtIncDec) + w.op(binOps[stmt.Op]) + w.expr(stmt.Lhs) + w.pos(stmt) + + case stmt.Op != 0 && stmt.Op != syntax.Def: + w.code(stmtAssignOp) + w.op(binOps[stmt.Op]) + w.expr(stmt.Lhs) + w.pos(stmt) + w.expr(stmt.Rhs) + + default: + w.code(stmtAssign) + w.pos(stmt) + w.assignList(stmt.Lhs) + w.exprList(stmt.Rhs) + } + + case *syntax.BlockStmt: + w.code(stmtBlock) + w.blockStmt(stmt) + + case *syntax.BranchStmt: + w.code(stmtBranch) + w.pos(stmt) + w.op(branchOps[stmt.Tok]) + w.optLabel(stmt.Label) + + case *syntax.CallStmt: + w.code(stmtCall) + w.pos(stmt) + w.op(callOps[stmt.Tok]) + w.expr(stmt.Call) + + case *syntax.DeclStmt: + for _, decl := range stmt.DeclList { + w.declStmt(decl) + } + + case *syntax.ExprStmt: + w.code(stmtExpr) + w.expr(stmt.X) + + case *syntax.ForStmt: + w.code(stmtFor) + w.forStmt(stmt) + + case *syntax.IfStmt: + w.code(stmtIf) + w.ifStmt(stmt) + + case *syntax.LabeledStmt: + w.code(stmtLabel) + w.pos(stmt) + w.label(stmt.Label) + w.stmt1(stmt.Stmt) + + case *syntax.ReturnStmt: + w.code(stmtReturn) + w.pos(stmt) + w.exprList(stmt.Results) + + case *syntax.SelectStmt: + w.code(stmtSelect) + w.selectStmt(stmt) + + case *syntax.SendStmt: + w.code(stmtSend) + w.pos(stmt) + w.expr(stmt.Chan) + w.expr(stmt.Value) + + case *syntax.SwitchStmt: + w.code(stmtSwitch) + w.switchStmt(stmt) + } +} + +func (w *writer) assignList(expr syntax.Expr) { + exprs := unpackListExpr(expr) + w.len(len(exprs)) + + for _, expr := range exprs { + if name, ok := expr.(*syntax.Name); ok && name.Value != "_" { + if obj, ok := w.p.info.Defs[name]; ok { + w.bool(true) + w.pos(obj) + w.localIdent(obj) + w.typ(obj.Type()) + + // TODO(mdempsky): Minimize locals index size by deferring + // this until the variables actually come into scope. + w.addLocal(obj) + continue + } + } + + w.bool(false) + w.expr(expr) + } +} + +func (w *writer) declStmt(decl syntax.Decl) { + switch decl := decl.(type) { + default: + w.p.unexpected("declaration", decl) + + case *syntax.ConstDecl: + + case *syntax.TypeDecl: + // Quirk: The legacy inliner doesn't support inlining functions + // with type declarations. Unified IR doesn't have any need to + // write out type declarations explicitly (they're always looked + // up via global index tables instead), so we just write out a + // marker so the reader knows to synthesize a fake declaration to + // prevent inlining. + if quirksMode() { + w.code(stmtTypeDeclHack) + } + + case *syntax.VarDecl: + values := unpackListExpr(decl.Values) + + // Quirk: When N variables are declared with N initialization + // values, we need to decompose that into N interleaved + // declarations+initializations, because it leads to different + // (albeit semantically equivalent) code generation. + if quirksMode() && len(decl.NameList) == len(values) { + for i, name := range decl.NameList { + w.code(stmtAssign) + w.pos(decl) + w.assignList(name) + w.exprList(values[i]) + } + break + } + + w.code(stmtAssign) + w.pos(decl) + w.assignList(namesAsExpr(decl.NameList)) + w.exprList(decl.Values) + } +} + +func (w *writer) blockStmt(stmt *syntax.BlockStmt) { + w.sync(syncBlockStmt) + w.openScope(stmt.Pos()) + w.stmts(stmt.List) + w.closeScope(stmt.Rbrace) +} + +func (w *writer) forStmt(stmt *syntax.ForStmt) { + w.sync(syncForStmt) + w.openScope(stmt.Pos()) + + if rang, ok := stmt.Init.(*syntax.RangeClause); w.bool(ok) { + w.pos(rang) + w.assignList(rang.Lhs) + w.expr(rang.X) + } else { + w.pos(stmt) + w.stmt(stmt.Init) + w.expr(stmt.Cond) + w.stmt(stmt.Post) + } + + w.blockStmt(stmt.Body) + w.closeAnotherScope() +} + +func (w *writer) ifStmt(stmt *syntax.IfStmt) { + w.sync(syncIfStmt) + w.openScope(stmt.Pos()) + w.pos(stmt) + w.stmt(stmt.Init) + w.expr(stmt.Cond) + w.blockStmt(stmt.Then) + w.stmt(stmt.Else) + w.closeAnotherScope() +} + +func (w *writer) selectStmt(stmt *syntax.SelectStmt) { + w.sync(syncSelectStmt) + + w.pos(stmt) + w.len(len(stmt.Body)) + for i, clause := range stmt.Body { + if i > 0 { + w.closeScope(clause.Pos()) + } + w.openScope(clause.Pos()) + + w.pos(clause) + w.stmt(clause.Comm) + w.stmts(clause.Body) + } + if len(stmt.Body) > 0 { + w.closeScope(stmt.Rbrace) + } +} + +func (w *writer) switchStmt(stmt *syntax.SwitchStmt) { + w.sync(syncSwitchStmt) + + w.openScope(stmt.Pos()) + w.pos(stmt) + w.stmt(stmt.Init) + w.expr(stmt.Tag) + + w.len(len(stmt.Body)) + for i, clause := range stmt.Body { + if i > 0 { + w.closeScope(clause.Pos()) + } + w.openScope(clause.Pos()) + + w.pos(clause) + w.exprList(clause.Cases) + + if obj, ok := w.p.info.Implicits[clause]; ok { + // TODO(mdempsky): These pos details are quirkish, but also + // necessary so the variable's position is correct for DWARF + // scope assignment later. It would probably be better for us to + // instead just set the variable's DWARF scoping info earlier so + // we can give it the correct position information. + pos := clause.Pos() + if typs := unpackListExpr(clause.Cases); len(typs) != 0 { + pos = typeExprEndPos(typs[len(typs)-1]) + } + w.pos(pos) + + obj := obj.(*types2.Var) + w.typ(obj.Type()) + w.addLocal(obj) + } + + w.stmts(clause.Body) + } + if len(stmt.Body) > 0 { + w.closeScope(stmt.Rbrace) + } + + w.closeScope(stmt.Rbrace) +} + +func (w *writer) label(label *syntax.Name) { + w.sync(syncLabel) + + // TODO(mdempsky): Replace label strings with dense indices. + w.string(label.Value) +} + +func (w *writer) optLabel(label *syntax.Name) { + w.sync(syncOptLabel) + if w.bool(label != nil) { + w.label(label) + } +} + +// @@@ Expressions + +func (w *writer) expr(expr syntax.Expr) { + expr = unparen(expr) // skip parens; unneeded after typecheck + + obj, targs := lookupObj(w.p.info, expr) + + if tv, ok := w.p.info.Types[expr]; ok { + if tv.IsType() { + w.code(exprType) + w.typ(tv.Type) + return + } + + if tv.Value != nil { + pos := expr.Pos() + if quirksMode() { + if obj != nil { + // Quirk: IR (and thus iexport) doesn't track position + // information for uses of declared objects. + pos = syntax.Pos{} + } else if tv.Value.Kind() == constant.String { + // Quirk: noder.sum picks a particular position for certain + // string concatenations. + pos = sumPos(expr) + } + } + + w.code(exprConst) + w.pos(pos) + w.value(tv.Type, tv.Value) + + // TODO(mdempsky): These details are only important for backend + // diagnostics. Explore writing them out separately. + w.op(constExprOp(expr)) + w.string(syntax.String(expr)) + return + } + } + + if obj != nil { + if _, ok := w.localsIdx[obj]; ok { + assert(len(targs) == 0) + w.code(exprLocal) + w.useLocal(obj) + return + } + + w.code(exprName) + w.obj(obj, targs) + return + } + + switch expr := expr.(type) { + default: + w.p.unexpected("expression", expr) + + case nil: // absent slice index, for condition, or switch tag + w.code(exprNone) + + case *syntax.Name: + assert(expr.Value == "_") + w.code(exprBlank) + + case *syntax.CompositeLit: + w.code(exprCompLit) + w.compLit(expr) + + case *syntax.FuncLit: + w.code(exprFuncLit) + w.funcLit(expr) + + case *syntax.SelectorExpr: + sel, ok := w.p.info.Selections[expr] + assert(ok) + + w.code(exprSelector) + w.expr(expr.X) + w.pos(expr) + w.selector(sel.Obj()) + + case *syntax.IndexExpr: + tv, ok := w.p.info.Types[expr.Index] + assert(ok && tv.IsValue()) + + w.code(exprIndex) + w.expr(expr.X) + w.pos(expr) + w.expr(expr.Index) + + case *syntax.SliceExpr: + w.code(exprSlice) + w.expr(expr.X) + w.pos(expr) + for _, n := range &expr.Index { + w.expr(n) + } + + case *syntax.AssertExpr: + w.code(exprAssert) + w.expr(expr.X) + w.pos(expr) + w.expr(expr.Type) + + case *syntax.Operation: + if expr.Y == nil { + w.code(exprUnaryOp) + w.op(unOps[expr.Op]) + w.pos(expr) + w.expr(expr.X) + break + } + + w.code(exprBinaryOp) + w.op(binOps[expr.Op]) + w.expr(expr.X) + w.pos(expr) + w.expr(expr.Y) + + case *syntax.CallExpr: + w.code(exprCall) + + if inf, ok := w.p.info.Inferred[expr]; ok { + obj, _ := lookupObj(w.p.info, expr.Fun) + assert(obj != nil) + + // As if w.expr(expr.Fun), but using inf.TArgs instead. + w.code(exprName) + w.obj(obj, inf.TArgs) + } else { + w.expr(expr.Fun) + } + + w.pos(expr) + w.exprs(expr.ArgList) + w.bool(expr.HasDots) + + case *syntax.TypeSwitchGuard: + w.code(exprTypeSwitchGuard) + w.pos(expr) + if tag := expr.Lhs; w.bool(tag != nil) { + w.pos(tag) + w.string(tag.Value) + } + w.expr(expr.X) + } +} + +func (w *writer) compLit(lit *syntax.CompositeLit) { + tv, ok := w.p.info.Types[lit] + assert(ok) + + w.sync(syncCompLit) + w.pos(lit) + w.typ(tv.Type) + + typ := tv.Type + if ptr, ok := typ.Underlying().(*types2.Pointer); ok { + typ = ptr.Elem() + } + str, isStruct := typ.Underlying().(*types2.Struct) + + w.len(len(lit.ElemList)) + for i, elem := range lit.ElemList { + if isStruct { + if kv, ok := elem.(*syntax.KeyValueExpr); ok { + // use position of expr.Key rather than of elem (which has position of ':') + w.pos(kv.Key) + w.len(fieldIndex(w.p.info, str, kv.Key.(*syntax.Name))) + elem = kv.Value + } else { + w.pos(elem) + w.len(i) + } + } else { + if kv, ok := elem.(*syntax.KeyValueExpr); w.bool(ok) { + // use position of expr.Key rather than of elem (which has position of ':') + w.pos(kv.Key) + w.expr(kv.Key) + elem = kv.Value + } + } + w.pos(elem) + w.expr(elem) + } +} + +func (w *writer) funcLit(expr *syntax.FuncLit) { + tv, ok := w.p.info.Types[expr] + assert(ok) + sig := tv.Type.(*types2.Signature) + + w.sync(syncFuncLit) + w.pos(expr) + w.pos(expr.Type) // for QuirksMode + w.signature(sig) + + closureVars, localsIdx := w.captureVars(expr) + w.len(len(closureVars)) + for _, closureVar := range closureVars { + w.pos(closureVar.pos) + w.useLocal(closureVar.obj) + } + + w.addBody(sig, expr.Body, localsIdx) +} + +type posObj struct { + pos syntax.Pos + obj types2.Object +} + +// captureVars returns the free variables used by the given function +// literal. +func (w *writer) captureVars(expr *syntax.FuncLit) (closureVars []posObj, localsIdx map[types2.Object]int) { + scope, ok := w.p.info.Scopes[expr.Type] + assert(ok) + + localsIdx = make(map[types2.Object]int) + + // TODO(mdempsky): This code needs to be cleaned up (e.g., to avoid + // traversing nested function literals multiple times). This will be + // easier after we drop quirks mode. + + var rbracePos syntax.Pos + + var visitor func(n syntax.Node) bool + visitor = func(n syntax.Node) bool { + + // Constant expressions don't count towards capturing. + if n, ok := n.(syntax.Expr); ok { + if tv, ok := w.p.info.Types[n]; ok && tv.Value != nil { + return true + } + } + + switch n := n.(type) { + case *syntax.Name: + if obj, ok := w.p.info.Uses[n].(*types2.Var); ok && !obj.IsField() && obj.Pkg() == w.p.curpkg && obj.Parent() != obj.Pkg().Scope() { + // Found a local variable. See if it chains up to scope. + parent := obj.Parent() + for { + if parent == scope { + break + } + if parent == obj.Pkg().Scope() { + if _, present := localsIdx[obj]; !present { + pos := rbracePos + if pos == (syntax.Pos{}) { + pos = n.Pos() + } + + idx := len(closureVars) + closureVars = append(closureVars, posObj{pos, obj}) + localsIdx[obj] = idx + } + break + } + parent = parent.Parent() + } + } + + case *syntax.FuncLit: + // Quirk: typecheck uses the rbrace position position of the + // function literal as the position of the intermediary capture. + if quirksMode() && rbracePos == (syntax.Pos{}) { + rbracePos = n.Body.Rbrace + syntax.Walk(n.Body, visitor) + rbracePos = syntax.Pos{} + return true + } + + case *syntax.AssignStmt: + // Quirk: typecheck visits (and thus captures) the RHS of + // assignment statements before the LHS. + if quirksMode() && (n.Op == 0 || n.Op == syntax.Def) { + syntax.Walk(n.Rhs, visitor) + syntax.Walk(n.Lhs, visitor) + return true + } + case *syntax.RangeClause: + // Quirk: Similarly, it visits the expression to be iterated + // over before the iteration variables. + if quirksMode() { + syntax.Walk(n.X, visitor) + if n.Lhs != nil { + syntax.Walk(n.Lhs, visitor) + } + return true + } + } + + return false + } + syntax.Walk(expr.Body, visitor) + + return +} + +func (w *writer) exprList(expr syntax.Expr) { + w.sync(syncExprList) + w.exprs(unpackListExpr(expr)) +} + +func (w *writer) exprs(exprs []syntax.Expr) { + if len(exprs) == 0 { + assert(exprs == nil) + } + + w.sync(syncExprs) + w.len(len(exprs)) + for _, expr := range exprs { + w.expr(expr) + } +} + +func (w *writer) op(op ir.Op) { + // TODO(mdempsky): Remove in favor of explicit codes? Would make + // export data more stable against internal refactorings, but low + // priority at the moment. + assert(op != 0) + w.sync(syncOp) + w.len(int(op)) +} + +// @@@ Package initialization + +// Caution: This code is still clumsy, because toolstash -cmp is +// particularly sensitive to it. + +type typeDeclGen struct { + *syntax.TypeDecl + gen int +} + +func (pw *pkgWriter) collectDecls(noders []*noder) { + var typegen int + + for _, p := range noders { + var importedEmbed, importedUnsafe bool + + syntax.Walk(p.file, func(n syntax.Node) bool { + switch n := n.(type) { + case *syntax.File: + pw.checkPragmas(n.Pragma, ir.GoBuildPragma, false) + + case *syntax.ImportDecl: + pw.checkPragmas(n.Pragma, 0, false) + + switch pkgNameOf(pw.info, n).Imported().Path() { + case "embed": + importedEmbed = true + case "unsafe": + importedUnsafe = true + } + + case *syntax.ConstDecl: + pw.checkPragmas(n.Pragma, 0, false) + + case *syntax.FuncDecl: + pw.checkPragmas(n.Pragma, funcPragmas, false) + + obj := pw.info.Defs[n.Name].(*types2.Func) + pw.funDecls[obj] = n + + case *syntax.TypeDecl: + obj := pw.info.Defs[n.Name].(*types2.TypeName) + d := typeDeclGen{TypeDecl: n} + + if n.Alias { + pw.checkPragmas(n.Pragma, 0, false) + } else { + pw.checkPragmas(n.Pragma, typePragmas, false) + + // Assign a unique ID to function-scoped defined types. + if !isGlobal(obj) { + typegen++ + d.gen = typegen + } + } + + pw.typDecls[obj] = d + + case *syntax.VarDecl: + pw.checkPragmas(n.Pragma, 0, true) + + if p, ok := n.Pragma.(*pragmas); ok && len(p.Embeds) > 0 { + obj := pw.info.Defs[n.NameList[0]].(*types2.Var) + // TODO(mdempsky): isGlobal(obj) gives false positive errors + // for //go:embed directives on package-scope blank + // variables. + if err := checkEmbed(n, importedEmbed, !isGlobal(obj)); err != nil { + pw.errorf(p.Embeds[0].Pos, "%s", err) + } + } + + // Workaround for #46208. For variable declarations that + // declare multiple variables and have an explicit type + // expression, the type expression is evaluated multiple + // times. This affects toolstash -cmp, because iexport is + // sensitive to *types.Type pointer identity. + if quirksMode() && n.Type != nil { + tv, ok := pw.info.Types[n.Type] + assert(ok) + assert(tv.IsType()) + for _, name := range n.NameList { + obj := pw.info.Defs[name].(*types2.Var) + pw.dups.add(obj.Type(), tv.Type) + } + } + } + return false + }) + + pw.cgoPragmas = append(pw.cgoPragmas, p.pragcgobuf...) + + for _, l := range p.linknames { + if !importedUnsafe { + pw.errorf(l.pos, "//go:linkname only allowed in Go files that import \"unsafe\"") + continue + } + + switch obj := pw.curpkg.Scope().Lookup(l.local).(type) { + case *types2.Func, *types2.Var: + if _, ok := pw.linknames[obj]; !ok { + pw.linknames[obj] = l.remote + } else { + pw.errorf(l.pos, "duplicate //go:linkname for %s", l.local) + } + + default: + // TODO(mdempsky): Enable after #42938 is fixed. + if false { + pw.errorf(l.pos, "//go:linkname must refer to declared function or variable") + } + } + } + } +} + +func (pw *pkgWriter) checkPragmas(p syntax.Pragma, allowed ir.PragmaFlag, embedOK bool) { + if p == nil { + return + } + pragma := p.(*pragmas) + + for _, pos := range pragma.Pos { + if pos.Flag&^allowed != 0 { + pw.errorf(pos.Pos, "misplaced compiler directive") + } + } + + if !embedOK { + for _, e := range pragma.Embeds { + pw.errorf(e.Pos, "misplaced go:embed directive") + } + } +} + +func (w *writer) pkgInit(noders []*noder) { + if quirksMode() { + posBases := posBasesOf(noders) + w.len(len(posBases)) + for _, posBase := range posBases { + w.posBase(posBase) + } + + objs := importedObjsOf(w.p.curpkg, w.p.info, noders) + w.len(len(objs)) + for _, obj := range objs { + w.qualifiedIdent(obj) + } + } + + w.len(len(w.p.cgoPragmas)) + for _, cgoPragma := range w.p.cgoPragmas { + w.strings(cgoPragma) + } + + w.sync(syncDecls) + for _, p := range noders { + for _, decl := range p.file.DeclList { + w.pkgDecl(decl) + } + } + w.code(declEnd) + + w.sync(syncEOF) +} + +func (w *writer) pkgDecl(decl syntax.Decl) { + switch decl := decl.(type) { + default: + w.p.unexpected("declaration", decl) + + case *syntax.ImportDecl: + + case *syntax.ConstDecl: + w.code(declOther) + w.pkgObjs(decl.NameList...) + + case *syntax.FuncDecl: + obj := w.p.info.Defs[decl.Name].(*types2.Func) + sig := obj.Type().(*types2.Signature) + + if sig.RParams() != nil || sig.TParams() != nil { + break // skip generic functions + } + + if recv := sig.Recv(); recv != nil && obj.Name() != "_" { + w.code(declMethod) + w.typ(recvBase(recv)) + w.selector(obj) + break + } + + w.code(declFunc) + w.pkgObjs(decl.Name) + + case *syntax.TypeDecl: + if len(decl.TParamList) != 0 { + break // skip generic type decls + } + + name := w.p.info.Defs[decl.Name].(*types2.TypeName) + + // Skip type declarations for interfaces that are only usable as + // type parameter bounds. + if iface, ok := name.Type().Underlying().(*types2.Interface); ok && iface.IsConstraint() { + break + } + + // Skip aliases to uninstantiated generic types. + // TODO(mdempsky): Revisit after #46477 is resolved. + if name.IsAlias() { + named, ok := name.Type().(*types2.Named) + if ok && len(named.TParams()) != 0 && len(named.TArgs()) == 0 { + break + } + } + + w.code(declOther) + w.pkgObjs(decl.Name) + + case *syntax.VarDecl: + w.code(declVar) + w.pos(decl) + w.pkgObjs(decl.NameList...) + w.exprList(decl.Values) + + var embeds []pragmaEmbed + if p, ok := decl.Pragma.(*pragmas); ok { + embeds = p.Embeds + } + w.len(len(embeds)) + for _, embed := range embeds { + w.pos(embed.Pos) + w.strings(embed.Patterns) + } + } +} + +func (w *writer) pkgObjs(names ...*syntax.Name) { + w.sync(syncDeclNames) + w.len(len(names)) + + for _, name := range names { + obj, ok := w.p.info.Defs[name] + assert(ok) + + w.sync(syncDeclName) + w.obj(obj, nil) + } +} + +// @@@ Helpers + +// isDefinedType reports whether obj is a defined type. +func isDefinedType(obj types2.Object) bool { + if obj, ok := obj.(*types2.TypeName); ok { + return !obj.IsAlias() + } + return false +} + +// isGlobal reports whether obj was declared at package scope. +// +// Caveat: blank objects are not declared. +func isGlobal(obj types2.Object) bool { + return obj.Parent() == obj.Pkg().Scope() +} + +// lookupObj returns the object that expr refers to, if any. If expr +// is an explicit instantiation of a generic object, then the type +// arguments are returned as well. +func lookupObj(info *types2.Info, expr syntax.Expr) (obj types2.Object, targs []types2.Type) { + if index, ok := expr.(*syntax.IndexExpr); ok { + if inf, ok := info.Inferred[index]; ok { + targs = inf.TArgs + } else { + args := unpackListExpr(index.Index) + + if len(args) == 1 { + tv, ok := info.Types[args[0]] + assert(ok) + if tv.IsValue() { + return // normal index expression + } + } + + targs = make([]types2.Type, len(args)) + for i, arg := range args { + tv, ok := info.Types[arg] + assert(ok) + assert(tv.IsType()) + targs[i] = tv.Type + } + } + + expr = index.X + } + + // Strip package qualifier, if present. + if sel, ok := expr.(*syntax.SelectorExpr); ok { + if !isPkgQual(info, sel) { + return // normal selector expression + } + expr = sel.Sel + } + + if name, ok := expr.(*syntax.Name); ok { + obj, _ = info.Uses[name] + } + return +} + +// isPkgQual reports whether the given selector expression is a +// package-qualified identifier. +func isPkgQual(info *types2.Info, sel *syntax.SelectorExpr) bool { + if name, ok := sel.X.(*syntax.Name); ok { + _, isPkgName := info.Uses[name].(*types2.PkgName) + return isPkgName + } + return false +} + +// recvBase returns the base type for the given receiver parameter. +func recvBase(recv *types2.Var) *types2.Named { + typ := recv.Type() + if ptr, ok := typ.(*types2.Pointer); ok { + typ = ptr.Elem() + } + return typ.(*types2.Named) +} + +// namesAsExpr returns a list of names as a syntax.Expr. +func namesAsExpr(names []*syntax.Name) syntax.Expr { + if len(names) == 1 { + return names[0] + } + + exprs := make([]syntax.Expr, len(names)) + for i, name := range names { + exprs[i] = name + } + return &syntax.ListExpr{ElemList: exprs} +} + +// fieldIndex returns the index of the struct field named by key. +func fieldIndex(info *types2.Info, str *types2.Struct, key *syntax.Name) int { + field := info.Uses[key].(*types2.Var) + + for i := 0; i < str.NumFields(); i++ { + if str.Field(i) == field { + return i + } + } + + panic(fmt.Sprintf("%s: %v is not a field of %v", key.Pos(), field, str)) +} + +// objTypeParams returns the type parameters on the given object. +func objTypeParams(obj types2.Object) []*types2.TypeName { + switch obj := obj.(type) { + case *types2.Func: + return obj.Type().(*types2.Signature).TParams() + case *types2.TypeName: + if !obj.IsAlias() { + return obj.Type().(*types2.Named).TParams() + } + } + return nil +} + +func asPragmaFlag(p syntax.Pragma) ir.PragmaFlag { + if p == nil { + return 0 + } + return p.(*pragmas).Flag +}