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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:25:22 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:25:22 +0000 |
commit | f6ad4dcef54c5ce997a4bad5a6d86de229015700 (patch) | |
tree | 7cfa4e31ace5c2bd95c72b154d15af494b2bcbef /src/cmd/internal/goobj | |
parent | Initial commit. (diff) | |
download | golang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.tar.xz golang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.zip |
Adding upstream version 1.22.1.upstream/1.22.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/cmd/internal/goobj')
-rw-r--r-- | src/cmd/internal/goobj/builtin.go | 47 | ||||
-rw-r--r-- | src/cmd/internal/goobj/builtinlist.go | 262 | ||||
-rw-r--r-- | src/cmd/internal/goobj/funcinfo.go | 145 | ||||
-rw-r--r-- | src/cmd/internal/goobj/mkbuiltin.go | 160 | ||||
-rw-r--r-- | src/cmd/internal/goobj/objfile.go | 882 | ||||
-rw-r--r-- | src/cmd/internal/goobj/objfile_test.go | 133 |
6 files changed, 1629 insertions, 0 deletions
diff --git a/src/cmd/internal/goobj/builtin.go b/src/cmd/internal/goobj/builtin.go new file mode 100644 index 0000000..aa665fd --- /dev/null +++ b/src/cmd/internal/goobj/builtin.go @@ -0,0 +1,47 @@ +// Copyright 2019 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 goobj + +import "internal/buildcfg" + +// Builtin (compiler-generated) function references appear +// frequently. We assign special indices for them, so they +// don't need to be referenced by name. + +// NBuiltin returns the number of listed builtin +// symbols. +func NBuiltin() int { + return len(builtins) +} + +// BuiltinName returns the name and ABI of the i-th +// builtin symbol. +func BuiltinName(i int) (string, int) { + return builtins[i].name, builtins[i].abi +} + +// BuiltinIdx returns the index of the builtin with the +// given name and abi, or -1 if it is not a builtin. +func BuiltinIdx(name string, abi int) int { + i, ok := builtinMap[name] + if !ok { + return -1 + } + if buildcfg.Experiment.RegabiWrappers && builtins[i].abi != abi { + return -1 + } + return i +} + +//go:generate go run mkbuiltin.go + +var builtinMap map[string]int + +func init() { + builtinMap = make(map[string]int, len(builtins)) + for i, b := range builtins { + builtinMap[b.name] = i + } +} diff --git a/src/cmd/internal/goobj/builtinlist.go b/src/cmd/internal/goobj/builtinlist.go new file mode 100644 index 0000000..fb729f5 --- /dev/null +++ b/src/cmd/internal/goobj/builtinlist.go @@ -0,0 +1,262 @@ +// Code generated by mkbuiltin.go. DO NOT EDIT. + +package goobj + +var builtins = [...]struct { + name string + abi int +}{ + {"runtime.newobject", 1}, + {"runtime.mallocgc", 1}, + {"runtime.panicdivide", 1}, + {"runtime.panicshift", 1}, + {"runtime.panicmakeslicelen", 1}, + {"runtime.panicmakeslicecap", 1}, + {"runtime.throwinit", 1}, + {"runtime.panicwrap", 1}, + {"runtime.gopanic", 1}, + {"runtime.gorecover", 1}, + {"runtime.goschedguarded", 1}, + {"runtime.goPanicIndex", 1}, + {"runtime.goPanicIndexU", 1}, + {"runtime.goPanicSliceAlen", 1}, + {"runtime.goPanicSliceAlenU", 1}, + {"runtime.goPanicSliceAcap", 1}, + {"runtime.goPanicSliceAcapU", 1}, + {"runtime.goPanicSliceB", 1}, + {"runtime.goPanicSliceBU", 1}, + {"runtime.goPanicSlice3Alen", 1}, + {"runtime.goPanicSlice3AlenU", 1}, + {"runtime.goPanicSlice3Acap", 1}, + {"runtime.goPanicSlice3AcapU", 1}, + {"runtime.goPanicSlice3B", 1}, + {"runtime.goPanicSlice3BU", 1}, + {"runtime.goPanicSlice3C", 1}, + {"runtime.goPanicSlice3CU", 1}, + {"runtime.goPanicSliceConvert", 1}, + {"runtime.printbool", 1}, + {"runtime.printfloat", 1}, + {"runtime.printint", 1}, + {"runtime.printhex", 1}, + {"runtime.printuint", 1}, + {"runtime.printcomplex", 1}, + {"runtime.printstring", 1}, + {"runtime.printpointer", 1}, + {"runtime.printuintptr", 1}, + {"runtime.printiface", 1}, + {"runtime.printeface", 1}, + {"runtime.printslice", 1}, + {"runtime.printnl", 1}, + {"runtime.printsp", 1}, + {"runtime.printlock", 1}, + {"runtime.printunlock", 1}, + {"runtime.concatstring2", 1}, + {"runtime.concatstring3", 1}, + {"runtime.concatstring4", 1}, + {"runtime.concatstring5", 1}, + {"runtime.concatstrings", 1}, + {"runtime.cmpstring", 1}, + {"runtime.intstring", 1}, + {"runtime.slicebytetostring", 1}, + {"runtime.slicebytetostringtmp", 1}, + {"runtime.slicerunetostring", 1}, + {"runtime.stringtoslicebyte", 1}, + {"runtime.stringtoslicerune", 1}, + {"runtime.slicecopy", 1}, + {"runtime.decoderune", 1}, + {"runtime.countrunes", 1}, + {"runtime.convT", 1}, + {"runtime.convTnoptr", 1}, + {"runtime.convT16", 1}, + {"runtime.convT32", 1}, + {"runtime.convT64", 1}, + {"runtime.convTstring", 1}, + {"runtime.convTslice", 1}, + {"runtime.assertE2I", 1}, + {"runtime.assertE2I2", 1}, + {"runtime.panicdottypeE", 1}, + {"runtime.panicdottypeI", 1}, + {"runtime.panicnildottype", 1}, + {"runtime.typeAssert", 1}, + {"runtime.interfaceSwitch", 1}, + {"runtime.ifaceeq", 1}, + {"runtime.efaceeq", 1}, + {"runtime.panicrangeexit", 1}, + {"runtime.deferrangefunc", 1}, + {"runtime.rand32", 1}, + {"runtime.makemap64", 1}, + {"runtime.makemap", 1}, + {"runtime.makemap_small", 1}, + {"runtime.mapaccess1", 1}, + {"runtime.mapaccess1_fast32", 1}, + {"runtime.mapaccess1_fast64", 1}, + {"runtime.mapaccess1_faststr", 1}, + {"runtime.mapaccess1_fat", 1}, + {"runtime.mapaccess2", 1}, + {"runtime.mapaccess2_fast32", 1}, + {"runtime.mapaccess2_fast64", 1}, + {"runtime.mapaccess2_faststr", 1}, + {"runtime.mapaccess2_fat", 1}, + {"runtime.mapassign", 1}, + {"runtime.mapassign_fast32", 1}, + {"runtime.mapassign_fast32ptr", 1}, + {"runtime.mapassign_fast64", 1}, + {"runtime.mapassign_fast64ptr", 1}, + {"runtime.mapassign_faststr", 1}, + {"runtime.mapiterinit", 1}, + {"runtime.mapdelete", 1}, + {"runtime.mapdelete_fast32", 1}, + {"runtime.mapdelete_fast64", 1}, + {"runtime.mapdelete_faststr", 1}, + {"runtime.mapiternext", 1}, + {"runtime.mapclear", 1}, + {"runtime.makechan64", 1}, + {"runtime.makechan", 1}, + {"runtime.chanrecv1", 1}, + {"runtime.chanrecv2", 1}, + {"runtime.chansend1", 1}, + {"runtime.closechan", 1}, + {"runtime.writeBarrier", 0}, + {"runtime.typedmemmove", 1}, + {"runtime.typedmemclr", 1}, + {"runtime.typedslicecopy", 1}, + {"runtime.selectnbsend", 1}, + {"runtime.selectnbrecv", 1}, + {"runtime.selectsetpc", 1}, + {"runtime.selectgo", 1}, + {"runtime.block", 1}, + {"runtime.makeslice", 1}, + {"runtime.makeslice64", 1}, + {"runtime.makeslicecopy", 1}, + {"runtime.growslice", 1}, + {"runtime.unsafeslicecheckptr", 1}, + {"runtime.panicunsafeslicelen", 1}, + {"runtime.panicunsafeslicenilptr", 1}, + {"runtime.unsafestringcheckptr", 1}, + {"runtime.panicunsafestringlen", 1}, + {"runtime.panicunsafestringnilptr", 1}, + {"runtime.memmove", 1}, + {"runtime.memclrNoHeapPointers", 1}, + {"runtime.memclrHasPointers", 1}, + {"runtime.memequal", 1}, + {"runtime.memequal0", 1}, + {"runtime.memequal8", 1}, + {"runtime.memequal16", 1}, + {"runtime.memequal32", 1}, + {"runtime.memequal64", 1}, + {"runtime.memequal128", 1}, + {"runtime.f32equal", 1}, + {"runtime.f64equal", 1}, + {"runtime.c64equal", 1}, + {"runtime.c128equal", 1}, + {"runtime.strequal", 1}, + {"runtime.interequal", 1}, + {"runtime.nilinterequal", 1}, + {"runtime.memhash", 1}, + {"runtime.memhash0", 1}, + {"runtime.memhash8", 1}, + {"runtime.memhash16", 1}, + {"runtime.memhash32", 1}, + {"runtime.memhash64", 1}, + {"runtime.memhash128", 1}, + {"runtime.f32hash", 1}, + {"runtime.f64hash", 1}, + {"runtime.c64hash", 1}, + {"runtime.c128hash", 1}, + {"runtime.strhash", 1}, + {"runtime.interhash", 1}, + {"runtime.nilinterhash", 1}, + {"runtime.int64div", 1}, + {"runtime.uint64div", 1}, + {"runtime.int64mod", 1}, + {"runtime.uint64mod", 1}, + {"runtime.float64toint64", 1}, + {"runtime.float64touint64", 1}, + {"runtime.float64touint32", 1}, + {"runtime.int64tofloat64", 1}, + {"runtime.int64tofloat32", 1}, + {"runtime.uint64tofloat64", 1}, + {"runtime.uint64tofloat32", 1}, + {"runtime.uint32tofloat64", 1}, + {"runtime.complex128div", 1}, + {"runtime.getcallerpc", 1}, + {"runtime.getcallersp", 1}, + {"runtime.racefuncenter", 1}, + {"runtime.racefuncexit", 1}, + {"runtime.raceread", 1}, + {"runtime.racewrite", 1}, + {"runtime.racereadrange", 1}, + {"runtime.racewriterange", 1}, + {"runtime.msanread", 1}, + {"runtime.msanwrite", 1}, + {"runtime.msanmove", 1}, + {"runtime.asanread", 1}, + {"runtime.asanwrite", 1}, + {"runtime.checkptrAlignment", 1}, + {"runtime.checkptrArithmetic", 1}, + {"runtime.libfuzzerTraceCmp1", 1}, + {"runtime.libfuzzerTraceCmp2", 1}, + {"runtime.libfuzzerTraceCmp4", 1}, + {"runtime.libfuzzerTraceCmp8", 1}, + {"runtime.libfuzzerTraceConstCmp1", 1}, + {"runtime.libfuzzerTraceConstCmp2", 1}, + {"runtime.libfuzzerTraceConstCmp4", 1}, + {"runtime.libfuzzerTraceConstCmp8", 1}, + {"runtime.libfuzzerHookStrCmp", 1}, + {"runtime.libfuzzerHookEqualFold", 1}, + {"runtime.addCovMeta", 1}, + {"runtime.x86HasPOPCNT", 0}, + {"runtime.x86HasSSE41", 0}, + {"runtime.x86HasFMA", 0}, + {"runtime.armHasVFPv4", 0}, + {"runtime.arm64HasATOMICS", 0}, + {"runtime.asanregisterglobals", 1}, + {"runtime.deferproc", 1}, + {"runtime.deferprocStack", 1}, + {"runtime.deferreturn", 1}, + {"runtime.newproc", 1}, + {"runtime.panicoverflow", 1}, + {"runtime.sigpanic", 1}, + {"runtime.gcWriteBarrier", 1}, + {"runtime.duffzero", 1}, + {"runtime.duffcopy", 1}, + {"runtime.morestack", 0}, + {"runtime.morestackc", 0}, + {"runtime.morestack_noctxt", 0}, + {"type:int8", 0}, + {"type:*int8", 0}, + {"type:uint8", 0}, + {"type:*uint8", 0}, + {"type:int16", 0}, + {"type:*int16", 0}, + {"type:uint16", 0}, + {"type:*uint16", 0}, + {"type:int32", 0}, + {"type:*int32", 0}, + {"type:uint32", 0}, + {"type:*uint32", 0}, + {"type:int64", 0}, + {"type:*int64", 0}, + {"type:uint64", 0}, + {"type:*uint64", 0}, + {"type:float32", 0}, + {"type:*float32", 0}, + {"type:float64", 0}, + {"type:*float64", 0}, + {"type:complex64", 0}, + {"type:*complex64", 0}, + {"type:complex128", 0}, + {"type:*complex128", 0}, + {"type:unsafe.Pointer", 0}, + {"type:*unsafe.Pointer", 0}, + {"type:uintptr", 0}, + {"type:*uintptr", 0}, + {"type:bool", 0}, + {"type:*bool", 0}, + {"type:string", 0}, + {"type:*string", 0}, + {"type:error", 0}, + {"type:*error", 0}, + {"type:func(error) string", 0}, + {"type:*func(error) string", 0}, +} diff --git a/src/cmd/internal/goobj/funcinfo.go b/src/cmd/internal/goobj/funcinfo.go new file mode 100644 index 0000000..9aa1188 --- /dev/null +++ b/src/cmd/internal/goobj/funcinfo.go @@ -0,0 +1,145 @@ +// Copyright 2019 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 goobj + +import ( + "bytes" + "encoding/binary" + "internal/abi" +) + +// CUFileIndex is used to index the filenames that are stored in the +// per-package/per-CU FileList. +type CUFileIndex uint32 + +// FuncInfo is serialized as a symbol (aux symbol). The symbol data is +// the binary encoding of the struct below. +type FuncInfo struct { + Args uint32 + Locals uint32 + FuncID abi.FuncID + FuncFlag abi.FuncFlag + StartLine int32 + File []CUFileIndex + InlTree []InlTreeNode +} + +func (a *FuncInfo) Write(w *bytes.Buffer) { + writeUint8 := func(x uint8) { + w.WriteByte(x) + } + var b [4]byte + writeUint32 := func(x uint32) { + binary.LittleEndian.PutUint32(b[:], x) + w.Write(b[:]) + } + + writeUint32(a.Args) + writeUint32(a.Locals) + writeUint8(uint8(a.FuncID)) + writeUint8(uint8(a.FuncFlag)) + writeUint8(0) // pad to uint32 boundary + writeUint8(0) + writeUint32(uint32(a.StartLine)) + + writeUint32(uint32(len(a.File))) + for _, f := range a.File { + writeUint32(uint32(f)) + } + writeUint32(uint32(len(a.InlTree))) + for i := range a.InlTree { + a.InlTree[i].Write(w) + } +} + +// FuncInfoLengths is a cache containing a roadmap of offsets and +// lengths for things within a serialized FuncInfo. Each length field +// stores the number of items (e.g. files, inltree nodes, etc), and the +// corresponding "off" field stores the byte offset of the start of +// the items in question. +type FuncInfoLengths struct { + NumFile uint32 + FileOff uint32 + NumInlTree uint32 + InlTreeOff uint32 + Initialized bool +} + +func (*FuncInfo) ReadFuncInfoLengths(b []byte) FuncInfoLengths { + var result FuncInfoLengths + + // Offset to the number of the file table. This value is determined by counting + // the number of bytes until we write funcdataoff to the file. + const numfileOff = 16 + result.NumFile = binary.LittleEndian.Uint32(b[numfileOff:]) + result.FileOff = numfileOff + 4 + + numinltreeOff := result.FileOff + 4*result.NumFile + result.NumInlTree = binary.LittleEndian.Uint32(b[numinltreeOff:]) + result.InlTreeOff = numinltreeOff + 4 + + result.Initialized = true + + return result +} + +func (*FuncInfo) ReadArgs(b []byte) uint32 { return binary.LittleEndian.Uint32(b) } + +func (*FuncInfo) ReadLocals(b []byte) uint32 { return binary.LittleEndian.Uint32(b[4:]) } + +func (*FuncInfo) ReadFuncID(b []byte) abi.FuncID { return abi.FuncID(b[8]) } + +func (*FuncInfo) ReadFuncFlag(b []byte) abi.FuncFlag { return abi.FuncFlag(b[9]) } + +func (*FuncInfo) ReadStartLine(b []byte) int32 { return int32(binary.LittleEndian.Uint32(b[12:])) } + +func (*FuncInfo) ReadFile(b []byte, filesoff uint32, k uint32) CUFileIndex { + return CUFileIndex(binary.LittleEndian.Uint32(b[filesoff+4*k:])) +} + +func (*FuncInfo) ReadInlTree(b []byte, inltreeoff uint32, k uint32) InlTreeNode { + const inlTreeNodeSize = 4 * 6 + var result InlTreeNode + result.Read(b[inltreeoff+k*inlTreeNodeSize:]) + return result +} + +// InlTreeNode is the serialized form of FileInfo.InlTree. +type InlTreeNode struct { + Parent int32 + File CUFileIndex + Line int32 + Func SymRef + ParentPC int32 +} + +func (inl *InlTreeNode) Write(w *bytes.Buffer) { + var b [4]byte + writeUint32 := func(x uint32) { + binary.LittleEndian.PutUint32(b[:], x) + w.Write(b[:]) + } + writeUint32(uint32(inl.Parent)) + writeUint32(uint32(inl.File)) + writeUint32(uint32(inl.Line)) + writeUint32(inl.Func.PkgIdx) + writeUint32(inl.Func.SymIdx) + writeUint32(uint32(inl.ParentPC)) +} + +// Read an InlTreeNode from b, return the remaining bytes. +func (inl *InlTreeNode) Read(b []byte) []byte { + readUint32 := func() uint32 { + x := binary.LittleEndian.Uint32(b) + b = b[4:] + return x + } + inl.Parent = int32(readUint32()) + inl.File = CUFileIndex(readUint32()) + inl.Line = int32(readUint32()) + inl.Func = SymRef{readUint32(), readUint32()} + inl.ParentPC = int32(readUint32()) + return b +} diff --git a/src/cmd/internal/goobj/mkbuiltin.go b/src/cmd/internal/goobj/mkbuiltin.go new file mode 100644 index 0000000..5ddf0e7 --- /dev/null +++ b/src/cmd/internal/goobj/mkbuiltin.go @@ -0,0 +1,160 @@ +// Copyright 2019 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. + +//go:build ignore + +// Generate builtinlist.go from cmd/compile/internal/typecheck/builtin/runtime.go. + +package main + +import ( + "bytes" + "flag" + "fmt" + "go/ast" + "go/format" + "go/parser" + "go/token" + "io" + "log" + "os" + "path/filepath" + "strings" +) + +var stdout = flag.Bool("stdout", false, "write to stdout instead of builtinlist.go") + +func main() { + flag.Parse() + + var b bytes.Buffer + fmt.Fprintln(&b, "// Code generated by mkbuiltin.go. DO NOT EDIT.") + fmt.Fprintln(&b) + fmt.Fprintln(&b, "package goobj") + + mkbuiltin(&b) + + out, err := format.Source(b.Bytes()) + if err != nil { + log.Fatal(err) + } + if *stdout { + _, err = os.Stdout.Write(out) + } else { + err = os.WriteFile("builtinlist.go", out, 0666) + } + if err != nil { + log.Fatal(err) + } +} + +func mkbuiltin(w io.Writer) { + pkg := "runtime" + fset := token.NewFileSet() + path := filepath.Join("..", "..", "compile", "internal", "typecheck", "_builtin", "runtime.go") + f, err := parser.ParseFile(fset, path, nil, 0) + if err != nil { + log.Fatal(err) + } + + decls := make(map[string]bool) + + fmt.Fprintf(w, "var builtins = [...]struct{ name string; abi int }{\n") + for _, decl := range f.Decls { + switch decl := decl.(type) { + case *ast.FuncDecl: + if decl.Recv != nil { + log.Fatal("methods unsupported") + } + if decl.Body != nil { + log.Fatal("unexpected function body") + } + declName := pkg + "." + decl.Name.Name + decls[declName] = true + fmt.Fprintf(w, "{%q, 1},\n", declName) // functions are ABIInternal (1) + case *ast.GenDecl: + if decl.Tok == token.IMPORT { + continue + } + if decl.Tok != token.VAR { + log.Fatal("unhandled declaration kind", decl.Tok) + } + for _, spec := range decl.Specs { + spec := spec.(*ast.ValueSpec) + if len(spec.Values) != 0 { + log.Fatal("unexpected values") + } + for _, name := range spec.Names { + declName := pkg + "." + name.Name + decls[declName] = true + fmt.Fprintf(w, "{%q, 0},\n", declName) // variables are ABI0 + } + } + default: + log.Fatal("unhandled decl type", decl) + } + } + + // The list above only contains ones that are used by the frontend. + // The backend may create more references of builtin functions. + // We also want to include predefined types. + // Add them. + extras := append(fextras[:], enumerateBasicTypes()...) + for _, b := range extras { + prefix := "" + if !strings.HasPrefix(b.name, "type:") { + prefix = pkg + "." + } + name := prefix + b.name + if decls[name] { + log.Fatalf("%q already added -- mkbuiltin.go out of sync?", name) + } + fmt.Fprintf(w, "{%q, %d},\n", name, b.abi) + } + fmt.Fprintln(w, "}") +} + +// enumerateBasicTypes returns the symbol names for basic types that are +// defined in the runtime and referenced in other packages. +// Needs to be kept in sync with reflect.go:WriteBasicTypes() and +// reflect.go:writeType() in the compiler. +func enumerateBasicTypes() []extra { + names := [...]string{ + "int8", "uint8", "int16", "uint16", + "int32", "uint32", "int64", "uint64", + "float32", "float64", "complex64", "complex128", + "unsafe.Pointer", "uintptr", "bool", "string", "error", + "func(error) string"} + result := []extra{} + for _, n := range names { + result = append(result, extra{"type:" + n, 0}) + result = append(result, extra{"type:*" + n, 0}) + } + return result +} + +type extra struct { + name string + abi int +} + +var fextras = [...]extra{ + // compiler frontend inserted calls (sysfunc) + {"deferproc", 1}, + {"deferprocStack", 1}, + {"deferreturn", 1}, + {"newproc", 1}, + {"panicoverflow", 1}, + {"sigpanic", 1}, + + // compiler backend inserted calls + {"gcWriteBarrier", 1}, + {"duffzero", 1}, + {"duffcopy", 1}, + + // assembler backend inserted calls + {"morestack", 0}, // asm function, ABI0 + {"morestackc", 0}, // asm function, ABI0 + {"morestack_noctxt", 0}, // asm function, ABI0 +} diff --git a/src/cmd/internal/goobj/objfile.go b/src/cmd/internal/goobj/objfile.go new file mode 100644 index 0000000..6c0f5e6 --- /dev/null +++ b/src/cmd/internal/goobj/objfile.go @@ -0,0 +1,882 @@ +// Copyright 2019 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This package defines the Go object file format, and provide "low-level" functions +// for reading and writing object files. + +// The object file is understood by the compiler, assembler, linker, and tools. They +// have "high level" code that operates on object files, handling application-specific +// logics, and use this package for the actual reading and writing. Specifically, the +// code below: +// +// - cmd/internal/obj/objfile.go (used by cmd/asm and cmd/compile) +// - cmd/internal/objfile/goobj.go (used cmd/nm, cmd/objdump) +// - cmd/link/internal/loader package (used by cmd/link) +// +// If the object file format changes, they may (or may not) need to change. + +package goobj + +import ( + "cmd/internal/bio" + "encoding/binary" + "errors" + "fmt" + "unsafe" +) + +// New object file format. +// +// Header struct { +// Magic [...]byte // "\x00go120ld" +// Fingerprint [8]byte +// Flags uint32 +// Offsets [...]uint32 // byte offset of each block below +// } +// +// Strings [...]struct { +// Data [...]byte +// } +// +// Autolib [...]struct { // imported packages (for file loading) +// Pkg string +// Fingerprint [8]byte +// } +// +// PkgIndex [...]string // referenced packages by index +// +// Files [...]string +// +// SymbolDefs [...]struct { +// Name string +// ABI uint16 +// Type uint8 +// Flag uint8 +// Flag2 uint8 +// Size uint32 +// } +// Hashed64Defs [...]struct { // short hashed (content-addressable) symbol definitions +// ... // same as SymbolDefs +// } +// HashedDefs [...]struct { // hashed (content-addressable) symbol definitions +// ... // same as SymbolDefs +// } +// NonPkgDefs [...]struct { // non-pkg symbol definitions +// ... // same as SymbolDefs +// } +// NonPkgRefs [...]struct { // non-pkg symbol references +// ... // same as SymbolDefs +// } +// +// RefFlags [...]struct { // referenced symbol flags +// Sym symRef +// Flag uint8 +// Flag2 uint8 +// } +// +// Hash64 [...][8]byte +// Hash [...][N]byte +// +// RelocIndex [...]uint32 // index to Relocs +// AuxIndex [...]uint32 // index to Aux +// DataIndex [...]uint32 // offset to Data +// +// Relocs [...]struct { +// Off int32 +// Size uint8 +// Type uint16 +// Add int64 +// Sym symRef +// } +// +// Aux [...]struct { +// Type uint8 +// Sym symRef +// } +// +// Data [...]byte +// +// // blocks only used by tools (objdump, nm) +// +// RefNames [...]struct { // referenced symbol names +// Sym symRef +// Name string +// // TODO: include ABI version as well? +// } +// +// string is encoded as is a uint32 length followed by a uint32 offset +// that points to the corresponding string bytes. +// +// symRef is struct { PkgIdx, SymIdx uint32 }. +// +// Slice type (e.g. []symRef) is encoded as a length prefix (uint32) +// followed by that number of elements. +// +// The types below correspond to the encoded data structure in the +// object file. + +// Symbol indexing. +// +// Each symbol is referenced with a pair of indices, { PkgIdx, SymIdx }, +// as the symRef struct above. +// +// PkgIdx is either a predeclared index (see PkgIdxNone below) or +// an index of an imported package. For the latter case, PkgIdx is the +// index of the package in the PkgIndex array. 0 is an invalid index. +// +// SymIdx is the index of the symbol in the given package. +// - If PkgIdx is PkgIdxSelf, SymIdx is the index of the symbol in the +// SymbolDefs array. +// - If PkgIdx is PkgIdxHashed64, SymIdx is the index of the symbol in the +// Hashed64Defs array. +// - If PkgIdx is PkgIdxHashed, SymIdx is the index of the symbol in the +// HashedDefs array. +// - If PkgIdx is PkgIdxNone, SymIdx is the index of the symbol in the +// NonPkgDefs array (could naturally overflow to NonPkgRefs array). +// - Otherwise, SymIdx is the index of the symbol in some other package's +// SymbolDefs array. +// +// {0, 0} represents a nil symbol. Otherwise PkgIdx should not be 0. +// +// Hash contains the content hashes of content-addressable symbols, of +// which PkgIdx is PkgIdxHashed, in the same order of HashedDefs array. +// Hash64 is similar, for PkgIdxHashed64 symbols. +// +// RelocIndex, AuxIndex, and DataIndex contains indices/offsets to +// Relocs/Aux/Data blocks, one element per symbol, first for all the +// defined symbols, then all the defined hashed and non-package symbols, +// in the same order of SymbolDefs/Hashed64Defs/HashedDefs/NonPkgDefs +// arrays. For N total defined symbols, the array is of length N+1. The +// last element is the total number of relocations (aux symbols, data +// blocks, etc.). +// +// They can be accessed by index. For the i-th symbol, its relocations +// are the RelocIndex[i]-th (inclusive) to RelocIndex[i+1]-th (exclusive) +// elements in the Relocs array. Aux/Data are likewise. (The index is +// 0-based.) + +// Auxiliary symbols. +// +// Each symbol may (or may not) be associated with a number of auxiliary +// symbols. They are described in the Aux block. See Aux struct below. +// Currently a symbol's Gotype, FuncInfo, and associated DWARF symbols +// are auxiliary symbols. + +const stringRefSize = 8 // two uint32s + +type FingerprintType [8]byte + +func (fp FingerprintType) IsZero() bool { return fp == FingerprintType{} } + +// Package Index. +const ( + PkgIdxNone = (1<<31 - 1) - iota // Non-package symbols + PkgIdxHashed64 // Short hashed (content-addressable) symbols + PkgIdxHashed // Hashed (content-addressable) symbols + PkgIdxBuiltin // Predefined runtime symbols (ex: runtime.newobject) + PkgIdxSelf // Symbols defined in the current package + PkgIdxSpecial = PkgIdxSelf // Indices above it has special meanings + PkgIdxInvalid = 0 + // The index of other referenced packages starts from 1. +) + +// Blocks +const ( + BlkAutolib = iota + BlkPkgIdx + BlkFile + BlkSymdef + BlkHashed64def + BlkHasheddef + BlkNonpkgdef + BlkNonpkgref + BlkRefFlags + BlkHash64 + BlkHash + BlkRelocIdx + BlkAuxIdx + BlkDataIdx + BlkReloc + BlkAux + BlkData + BlkRefName + BlkEnd + NBlk +) + +// File header. +// TODO: probably no need to export this. +type Header struct { + Magic string + Fingerprint FingerprintType + Flags uint32 + Offsets [NBlk]uint32 +} + +const Magic = "\x00go120ld" + +func (h *Header) Write(w *Writer) { + w.RawString(h.Magic) + w.Bytes(h.Fingerprint[:]) + w.Uint32(h.Flags) + for _, x := range h.Offsets { + w.Uint32(x) + } +} + +func (h *Header) Read(r *Reader) error { + b := r.BytesAt(0, len(Magic)) + h.Magic = string(b) + if h.Magic != Magic { + return errors.New("wrong magic, not a Go object file") + } + off := uint32(len(h.Magic)) + copy(h.Fingerprint[:], r.BytesAt(off, len(h.Fingerprint))) + off += 8 + h.Flags = r.uint32At(off) + off += 4 + for i := range h.Offsets { + h.Offsets[i] = r.uint32At(off) + off += 4 + } + return nil +} + +func (h *Header) Size() int { + return len(h.Magic) + len(h.Fingerprint) + 4 + 4*len(h.Offsets) +} + +// Autolib +type ImportedPkg struct { + Pkg string + Fingerprint FingerprintType +} + +const importedPkgSize = stringRefSize + 8 + +func (p *ImportedPkg) Write(w *Writer) { + w.StringRef(p.Pkg) + w.Bytes(p.Fingerprint[:]) +} + +// Symbol definition. +// +// Serialized format: +// +// Sym struct { +// Name string +// ABI uint16 +// Type uint8 +// Flag uint8 +// Flag2 uint8 +// Siz uint32 +// Align uint32 +// } +type Sym [SymSize]byte + +const SymSize = stringRefSize + 2 + 1 + 1 + 1 + 4 + 4 + +const SymABIstatic = ^uint16(0) + +const ( + ObjFlagShared = 1 << iota // this object is built with -shared + _ // was ObjFlagNeedNameExpansion + ObjFlagFromAssembly // object is from asm src, not go + ObjFlagUnlinkable // unlinkable package (linker will emit an error) +) + +// Sym.Flag +const ( + SymFlagDupok = 1 << iota + SymFlagLocal + SymFlagTypelink + SymFlagLeaf + SymFlagNoSplit + SymFlagReflectMethod + SymFlagGoType +) + +// Sym.Flag2 +const ( + SymFlagUsedInIface = 1 << iota + SymFlagItab + SymFlagDict + SymFlagPkgInit +) + +// Returns the length of the name of the symbol. +func (s *Sym) NameLen(r *Reader) int { + return int(binary.LittleEndian.Uint32(s[:])) +} + +func (s *Sym) Name(r *Reader) string { + len := binary.LittleEndian.Uint32(s[:]) + off := binary.LittleEndian.Uint32(s[4:]) + return r.StringAt(off, len) +} + +func (s *Sym) ABI() uint16 { return binary.LittleEndian.Uint16(s[8:]) } +func (s *Sym) Type() uint8 { return s[10] } +func (s *Sym) Flag() uint8 { return s[11] } +func (s *Sym) Flag2() uint8 { return s[12] } +func (s *Sym) Siz() uint32 { return binary.LittleEndian.Uint32(s[13:]) } +func (s *Sym) Align() uint32 { return binary.LittleEndian.Uint32(s[17:]) } + +func (s *Sym) Dupok() bool { return s.Flag()&SymFlagDupok != 0 } +func (s *Sym) Local() bool { return s.Flag()&SymFlagLocal != 0 } +func (s *Sym) Typelink() bool { return s.Flag()&SymFlagTypelink != 0 } +func (s *Sym) Leaf() bool { return s.Flag()&SymFlagLeaf != 0 } +func (s *Sym) NoSplit() bool { return s.Flag()&SymFlagNoSplit != 0 } +func (s *Sym) ReflectMethod() bool { return s.Flag()&SymFlagReflectMethod != 0 } +func (s *Sym) IsGoType() bool { return s.Flag()&SymFlagGoType != 0 } +func (s *Sym) UsedInIface() bool { return s.Flag2()&SymFlagUsedInIface != 0 } +func (s *Sym) IsItab() bool { return s.Flag2()&SymFlagItab != 0 } +func (s *Sym) IsDict() bool { return s.Flag2()&SymFlagDict != 0 } +func (s *Sym) IsPkgInit() bool { return s.Flag2()&SymFlagPkgInit != 0 } + +func (s *Sym) SetName(x string, w *Writer) { + binary.LittleEndian.PutUint32(s[:], uint32(len(x))) + binary.LittleEndian.PutUint32(s[4:], w.stringOff(x)) +} + +func (s *Sym) SetABI(x uint16) { binary.LittleEndian.PutUint16(s[8:], x) } +func (s *Sym) SetType(x uint8) { s[10] = x } +func (s *Sym) SetFlag(x uint8) { s[11] = x } +func (s *Sym) SetFlag2(x uint8) { s[12] = x } +func (s *Sym) SetSiz(x uint32) { binary.LittleEndian.PutUint32(s[13:], x) } +func (s *Sym) SetAlign(x uint32) { binary.LittleEndian.PutUint32(s[17:], x) } + +func (s *Sym) Write(w *Writer) { w.Bytes(s[:]) } + +// for testing +func (s *Sym) fromBytes(b []byte) { copy(s[:], b) } + +// Symbol reference. +type SymRef struct { + PkgIdx uint32 + SymIdx uint32 +} + +func (s SymRef) IsZero() bool { return s == SymRef{} } + +// Hash64 +type Hash64Type [Hash64Size]byte + +const Hash64Size = 8 + +// Hash +type HashType [HashSize]byte + +const HashSize = 16 // truncated SHA256 + +// Relocation. +// +// Serialized format: +// +// Reloc struct { +// Off int32 +// Siz uint8 +// Type uint16 +// Add int64 +// Sym SymRef +// } +type Reloc [RelocSize]byte + +const RelocSize = 4 + 1 + 2 + 8 + 8 + +func (r *Reloc) Off() int32 { return int32(binary.LittleEndian.Uint32(r[:])) } +func (r *Reloc) Siz() uint8 { return r[4] } +func (r *Reloc) Type() uint16 { return binary.LittleEndian.Uint16(r[5:]) } +func (r *Reloc) Add() int64 { return int64(binary.LittleEndian.Uint64(r[7:])) } +func (r *Reloc) Sym() SymRef { + return SymRef{binary.LittleEndian.Uint32(r[15:]), binary.LittleEndian.Uint32(r[19:])} +} + +func (r *Reloc) SetOff(x int32) { binary.LittleEndian.PutUint32(r[:], uint32(x)) } +func (r *Reloc) SetSiz(x uint8) { r[4] = x } +func (r *Reloc) SetType(x uint16) { binary.LittleEndian.PutUint16(r[5:], x) } +func (r *Reloc) SetAdd(x int64) { binary.LittleEndian.PutUint64(r[7:], uint64(x)) } +func (r *Reloc) SetSym(x SymRef) { + binary.LittleEndian.PutUint32(r[15:], x.PkgIdx) + binary.LittleEndian.PutUint32(r[19:], x.SymIdx) +} + +func (r *Reloc) Set(off int32, size uint8, typ uint16, add int64, sym SymRef) { + r.SetOff(off) + r.SetSiz(size) + r.SetType(typ) + r.SetAdd(add) + r.SetSym(sym) +} + +func (r *Reloc) Write(w *Writer) { w.Bytes(r[:]) } + +// for testing +func (r *Reloc) fromBytes(b []byte) { copy(r[:], b) } + +// Aux symbol info. +// +// Serialized format: +// +// Aux struct { +// Type uint8 +// Sym SymRef +// } +type Aux [AuxSize]byte + +const AuxSize = 1 + 8 + +// Aux Type +const ( + AuxGotype = iota + AuxFuncInfo + AuxFuncdata + AuxDwarfInfo + AuxDwarfLoc + AuxDwarfRanges + AuxDwarfLines + AuxPcsp + AuxPcfile + AuxPcline + AuxPcinline + AuxPcdata + AuxWasmImport + AuxSehUnwindInfo +) + +func (a *Aux) Type() uint8 { return a[0] } +func (a *Aux) Sym() SymRef { + return SymRef{binary.LittleEndian.Uint32(a[1:]), binary.LittleEndian.Uint32(a[5:])} +} + +func (a *Aux) SetType(x uint8) { a[0] = x } +func (a *Aux) SetSym(x SymRef) { + binary.LittleEndian.PutUint32(a[1:], x.PkgIdx) + binary.LittleEndian.PutUint32(a[5:], x.SymIdx) +} + +func (a *Aux) Write(w *Writer) { w.Bytes(a[:]) } + +// for testing +func (a *Aux) fromBytes(b []byte) { copy(a[:], b) } + +// Referenced symbol flags. +// +// Serialized format: +// +// RefFlags struct { +// Sym symRef +// Flag uint8 +// Flag2 uint8 +// } +type RefFlags [RefFlagsSize]byte + +const RefFlagsSize = 8 + 1 + 1 + +func (r *RefFlags) Sym() SymRef { + return SymRef{binary.LittleEndian.Uint32(r[:]), binary.LittleEndian.Uint32(r[4:])} +} +func (r *RefFlags) Flag() uint8 { return r[8] } +func (r *RefFlags) Flag2() uint8 { return r[9] } + +func (r *RefFlags) SetSym(x SymRef) { + binary.LittleEndian.PutUint32(r[:], x.PkgIdx) + binary.LittleEndian.PutUint32(r[4:], x.SymIdx) +} +func (r *RefFlags) SetFlag(x uint8) { r[8] = x } +func (r *RefFlags) SetFlag2(x uint8) { r[9] = x } + +func (r *RefFlags) Write(w *Writer) { w.Bytes(r[:]) } + +// Used to construct an artificially large array type when reading an +// item from the object file relocs section or aux sym section (needs +// to work on 32-bit as well as 64-bit). See issue 41621. +const huge = (1<<31 - 1) / RelocSize + +// Referenced symbol name. +// +// Serialized format: +// +// RefName struct { +// Sym symRef +// Name string +// } +type RefName [RefNameSize]byte + +const RefNameSize = 8 + stringRefSize + +func (n *RefName) Sym() SymRef { + return SymRef{binary.LittleEndian.Uint32(n[:]), binary.LittleEndian.Uint32(n[4:])} +} +func (n *RefName) Name(r *Reader) string { + len := binary.LittleEndian.Uint32(n[8:]) + off := binary.LittleEndian.Uint32(n[12:]) + return r.StringAt(off, len) +} + +func (n *RefName) SetSym(x SymRef) { + binary.LittleEndian.PutUint32(n[:], x.PkgIdx) + binary.LittleEndian.PutUint32(n[4:], x.SymIdx) +} +func (n *RefName) SetName(x string, w *Writer) { + binary.LittleEndian.PutUint32(n[8:], uint32(len(x))) + binary.LittleEndian.PutUint32(n[12:], w.stringOff(x)) +} + +func (n *RefName) Write(w *Writer) { w.Bytes(n[:]) } + +type Writer struct { + wr *bio.Writer + stringMap map[string]uint32 + off uint32 // running offset + + b [8]byte // scratch space for writing bytes +} + +func NewWriter(wr *bio.Writer) *Writer { + return &Writer{wr: wr, stringMap: make(map[string]uint32)} +} + +func (w *Writer) AddString(s string) { + if _, ok := w.stringMap[s]; ok { + return + } + w.stringMap[s] = w.off + w.RawString(s) +} + +func (w *Writer) stringOff(s string) uint32 { + off, ok := w.stringMap[s] + if !ok { + panic(fmt.Sprintf("writeStringRef: string not added: %q", s)) + } + return off +} + +func (w *Writer) StringRef(s string) { + w.Uint32(uint32(len(s))) + w.Uint32(w.stringOff(s)) +} + +func (w *Writer) RawString(s string) { + w.wr.WriteString(s) + w.off += uint32(len(s)) +} + +func (w *Writer) Bytes(s []byte) { + w.wr.Write(s) + w.off += uint32(len(s)) +} + +func (w *Writer) Uint64(x uint64) { + binary.LittleEndian.PutUint64(w.b[:], x) + w.wr.Write(w.b[:]) + w.off += 8 +} + +func (w *Writer) Uint32(x uint32) { + binary.LittleEndian.PutUint32(w.b[:4], x) + w.wr.Write(w.b[:4]) + w.off += 4 +} + +func (w *Writer) Uint16(x uint16) { + binary.LittleEndian.PutUint16(w.b[:2], x) + w.wr.Write(w.b[:2]) + w.off += 2 +} + +func (w *Writer) Uint8(x uint8) { + w.wr.WriteByte(x) + w.off++ +} + +func (w *Writer) Offset() uint32 { + return w.off +} + +type Reader struct { + b []byte // mmapped bytes, if not nil + readonly bool // whether b is backed with read-only memory + + start uint32 + h Header // keep block offsets +} + +func NewReaderFromBytes(b []byte, readonly bool) *Reader { + r := &Reader{b: b, readonly: readonly, start: 0} + err := r.h.Read(r) + if err != nil { + return nil + } + return r +} + +func (r *Reader) BytesAt(off uint32, len int) []byte { + if len == 0 { + return nil + } + end := int(off) + len + return r.b[int(off):end:end] +} + +func (r *Reader) uint64At(off uint32) uint64 { + b := r.BytesAt(off, 8) + return binary.LittleEndian.Uint64(b) +} + +func (r *Reader) int64At(off uint32) int64 { + return int64(r.uint64At(off)) +} + +func (r *Reader) uint32At(off uint32) uint32 { + b := r.BytesAt(off, 4) + return binary.LittleEndian.Uint32(b) +} + +func (r *Reader) int32At(off uint32) int32 { + return int32(r.uint32At(off)) +} + +func (r *Reader) uint16At(off uint32) uint16 { + b := r.BytesAt(off, 2) + return binary.LittleEndian.Uint16(b) +} + +func (r *Reader) uint8At(off uint32) uint8 { + b := r.BytesAt(off, 1) + return b[0] +} + +func (r *Reader) StringAt(off uint32, len uint32) string { + b := r.b[off : off+len] + if r.readonly { + return toString(b) // backed by RO memory, ok to make unsafe string + } + return string(b) +} + +func toString(b []byte) string { + if len(b) == 0 { + return "" + } + return unsafe.String(&b[0], len(b)) +} + +func (r *Reader) StringRef(off uint32) string { + l := r.uint32At(off) + return r.StringAt(r.uint32At(off+4), l) +} + +func (r *Reader) Fingerprint() FingerprintType { + return r.h.Fingerprint +} + +func (r *Reader) Autolib() []ImportedPkg { + n := (r.h.Offsets[BlkAutolib+1] - r.h.Offsets[BlkAutolib]) / importedPkgSize + s := make([]ImportedPkg, n) + off := r.h.Offsets[BlkAutolib] + for i := range s { + s[i].Pkg = r.StringRef(off) + copy(s[i].Fingerprint[:], r.BytesAt(off+stringRefSize, len(s[i].Fingerprint))) + off += importedPkgSize + } + return s +} + +func (r *Reader) Pkglist() []string { + n := (r.h.Offsets[BlkPkgIdx+1] - r.h.Offsets[BlkPkgIdx]) / stringRefSize + s := make([]string, n) + off := r.h.Offsets[BlkPkgIdx] + for i := range s { + s[i] = r.StringRef(off) + off += stringRefSize + } + return s +} + +func (r *Reader) NPkg() int { + return int(r.h.Offsets[BlkPkgIdx+1]-r.h.Offsets[BlkPkgIdx]) / stringRefSize +} + +func (r *Reader) Pkg(i int) string { + off := r.h.Offsets[BlkPkgIdx] + uint32(i)*stringRefSize + return r.StringRef(off) +} + +func (r *Reader) NFile() int { + return int(r.h.Offsets[BlkFile+1]-r.h.Offsets[BlkFile]) / stringRefSize +} + +func (r *Reader) File(i int) string { + off := r.h.Offsets[BlkFile] + uint32(i)*stringRefSize + return r.StringRef(off) +} + +func (r *Reader) NSym() int { + return int(r.h.Offsets[BlkSymdef+1]-r.h.Offsets[BlkSymdef]) / SymSize +} + +func (r *Reader) NHashed64def() int { + return int(r.h.Offsets[BlkHashed64def+1]-r.h.Offsets[BlkHashed64def]) / SymSize +} + +func (r *Reader) NHasheddef() int { + return int(r.h.Offsets[BlkHasheddef+1]-r.h.Offsets[BlkHasheddef]) / SymSize +} + +func (r *Reader) NNonpkgdef() int { + return int(r.h.Offsets[BlkNonpkgdef+1]-r.h.Offsets[BlkNonpkgdef]) / SymSize +} + +func (r *Reader) NNonpkgref() int { + return int(r.h.Offsets[BlkNonpkgref+1]-r.h.Offsets[BlkNonpkgref]) / SymSize +} + +// SymOff returns the offset of the i-th symbol. +func (r *Reader) SymOff(i uint32) uint32 { + return r.h.Offsets[BlkSymdef] + uint32(i*SymSize) +} + +// Sym returns a pointer to the i-th symbol. +func (r *Reader) Sym(i uint32) *Sym { + off := r.SymOff(i) + return (*Sym)(unsafe.Pointer(&r.b[off])) +} + +// NRefFlags returns the number of referenced symbol flags. +func (r *Reader) NRefFlags() int { + return int(r.h.Offsets[BlkRefFlags+1]-r.h.Offsets[BlkRefFlags]) / RefFlagsSize +} + +// RefFlags returns a pointer to the i-th referenced symbol flags. +// Note: here i is not a local symbol index, just a counter. +func (r *Reader) RefFlags(i int) *RefFlags { + off := r.h.Offsets[BlkRefFlags] + uint32(i*RefFlagsSize) + return (*RefFlags)(unsafe.Pointer(&r.b[off])) +} + +// Hash64 returns the i-th short hashed symbol's hash. +// Note: here i is the index of short hashed symbols, not all symbols +// (unlike other accessors). +func (r *Reader) Hash64(i uint32) uint64 { + off := r.h.Offsets[BlkHash64] + uint32(i*Hash64Size) + return r.uint64At(off) +} + +// Hash returns a pointer to the i-th hashed symbol's hash. +// Note: here i is the index of hashed symbols, not all symbols +// (unlike other accessors). +func (r *Reader) Hash(i uint32) *HashType { + off := r.h.Offsets[BlkHash] + uint32(i*HashSize) + return (*HashType)(unsafe.Pointer(&r.b[off])) +} + +// NReloc returns the number of relocations of the i-th symbol. +func (r *Reader) NReloc(i uint32) int { + relocIdxOff := r.h.Offsets[BlkRelocIdx] + uint32(i*4) + return int(r.uint32At(relocIdxOff+4) - r.uint32At(relocIdxOff)) +} + +// RelocOff returns the offset of the j-th relocation of the i-th symbol. +func (r *Reader) RelocOff(i uint32, j int) uint32 { + relocIdxOff := r.h.Offsets[BlkRelocIdx] + uint32(i*4) + relocIdx := r.uint32At(relocIdxOff) + return r.h.Offsets[BlkReloc] + (relocIdx+uint32(j))*uint32(RelocSize) +} + +// Reloc returns a pointer to the j-th relocation of the i-th symbol. +func (r *Reader) Reloc(i uint32, j int) *Reloc { + off := r.RelocOff(i, j) + return (*Reloc)(unsafe.Pointer(&r.b[off])) +} + +// Relocs returns a pointer to the relocations of the i-th symbol. +func (r *Reader) Relocs(i uint32) []Reloc { + off := r.RelocOff(i, 0) + n := r.NReloc(i) + return (*[huge]Reloc)(unsafe.Pointer(&r.b[off]))[:n:n] +} + +// NAux returns the number of aux symbols of the i-th symbol. +func (r *Reader) NAux(i uint32) int { + auxIdxOff := r.h.Offsets[BlkAuxIdx] + i*4 + return int(r.uint32At(auxIdxOff+4) - r.uint32At(auxIdxOff)) +} + +// AuxOff returns the offset of the j-th aux symbol of the i-th symbol. +func (r *Reader) AuxOff(i uint32, j int) uint32 { + auxIdxOff := r.h.Offsets[BlkAuxIdx] + i*4 + auxIdx := r.uint32At(auxIdxOff) + return r.h.Offsets[BlkAux] + (auxIdx+uint32(j))*uint32(AuxSize) +} + +// Aux returns a pointer to the j-th aux symbol of the i-th symbol. +func (r *Reader) Aux(i uint32, j int) *Aux { + off := r.AuxOff(i, j) + return (*Aux)(unsafe.Pointer(&r.b[off])) +} + +// Auxs returns the aux symbols of the i-th symbol. +func (r *Reader) Auxs(i uint32) []Aux { + off := r.AuxOff(i, 0) + n := r.NAux(i) + return (*[huge]Aux)(unsafe.Pointer(&r.b[off]))[:n:n] +} + +// DataOff returns the offset of the i-th symbol's data. +func (r *Reader) DataOff(i uint32) uint32 { + dataIdxOff := r.h.Offsets[BlkDataIdx] + i*4 + return r.h.Offsets[BlkData] + r.uint32At(dataIdxOff) +} + +// DataSize returns the size of the i-th symbol's data. +func (r *Reader) DataSize(i uint32) int { + dataIdxOff := r.h.Offsets[BlkDataIdx] + i*4 + return int(r.uint32At(dataIdxOff+4) - r.uint32At(dataIdxOff)) +} + +// Data returns the i-th symbol's data. +func (r *Reader) Data(i uint32) []byte { + dataIdxOff := r.h.Offsets[BlkDataIdx] + i*4 + base := r.h.Offsets[BlkData] + off := r.uint32At(dataIdxOff) + end := r.uint32At(dataIdxOff + 4) + return r.BytesAt(base+off, int(end-off)) +} + +// DataString returns the i-th symbol's data as a string. +func (r *Reader) DataString(i uint32) string { + dataIdxOff := r.h.Offsets[BlkDataIdx] + i*4 + base := r.h.Offsets[BlkData] + off := r.uint32At(dataIdxOff) + end := r.uint32At(dataIdxOff + 4) + return r.StringAt(base+off, end-off) +} + +// NRefName returns the number of referenced symbol names. +func (r *Reader) NRefName() int { + return int(r.h.Offsets[BlkRefName+1]-r.h.Offsets[BlkRefName]) / RefNameSize +} + +// RefName returns a pointer to the i-th referenced symbol name. +// Note: here i is not a local symbol index, just a counter. +func (r *Reader) RefName(i int) *RefName { + off := r.h.Offsets[BlkRefName] + uint32(i*RefNameSize) + return (*RefName)(unsafe.Pointer(&r.b[off])) +} + +// ReadOnly returns whether r.BytesAt returns read-only bytes. +func (r *Reader) ReadOnly() bool { + return r.readonly +} + +// Flags returns the flag bits read from the object file header. +func (r *Reader) Flags() uint32 { + return r.h.Flags +} + +func (r *Reader) Shared() bool { return r.Flags()&ObjFlagShared != 0 } +func (r *Reader) FromAssembly() bool { return r.Flags()&ObjFlagFromAssembly != 0 } +func (r *Reader) Unlinkable() bool { return r.Flags()&ObjFlagUnlinkable != 0 } diff --git a/src/cmd/internal/goobj/objfile_test.go b/src/cmd/internal/goobj/objfile_test.go new file mode 100644 index 0000000..10e0564 --- /dev/null +++ b/src/cmd/internal/goobj/objfile_test.go @@ -0,0 +1,133 @@ +// Copyright 2020 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 goobj + +import ( + "bufio" + "bytes" + "fmt" + "internal/buildcfg" + "internal/testenv" + "os" + "testing" + + "cmd/internal/bio" + "cmd/internal/objabi" +) + +func dummyWriter(buf *bytes.Buffer) *Writer { + wr := &bio.Writer{Writer: bufio.NewWriter(buf)} // hacky: no file, so cannot seek + return NewWriter(wr) +} + +func TestReadWrite(t *testing.T) { + // Test that we get the same data in a write-read roundtrip. + + // Write a symbol, a relocation, and an aux info. + var buf bytes.Buffer + w := dummyWriter(&buf) + + var s Sym + s.SetABI(1) + s.SetType(uint8(objabi.STEXT)) + s.SetFlag(0x12) + s.SetSiz(12345) + s.SetAlign(8) + s.Write(w) + + var r Reloc + r.SetOff(12) + r.SetSiz(4) + r.SetType(uint16(objabi.R_ADDR)) + r.SetAdd(54321) + r.SetSym(SymRef{11, 22}) + r.Write(w) + + var a Aux + a.SetType(AuxFuncInfo) + a.SetSym(SymRef{33, 44}) + a.Write(w) + + w.wr.Flush() + + // Read them back and check. + b := buf.Bytes() + var s2 Sym + s2.fromBytes(b) + if s2.ABI() != 1 || s2.Type() != uint8(objabi.STEXT) || s2.Flag() != 0x12 || s2.Siz() != 12345 || s2.Align() != 8 { + t.Errorf("read Sym2 mismatch: got %v %v %v %v %v", s2.ABI(), s2.Type(), s2.Flag(), s2.Siz(), s2.Align()) + } + + b = b[SymSize:] + var r2 Reloc + r2.fromBytes(b) + if r2.Off() != 12 || r2.Siz() != 4 || r2.Type() != uint16(objabi.R_ADDR) || r2.Add() != 54321 || r2.Sym() != (SymRef{11, 22}) { + t.Errorf("read Reloc2 mismatch: got %v %v %v %v %v", r2.Off(), r2.Siz(), r2.Type(), r2.Add(), r2.Sym()) + } + + b = b[RelocSize:] + var a2 Aux + a2.fromBytes(b) + if a2.Type() != AuxFuncInfo || a2.Sym() != (SymRef{33, 44}) { + t.Errorf("read Aux2 mismatch: got %v %v", a2.Type(), a2.Sym()) + } +} + +var issue41621prolog = ` +package main +var lines = []string{ +` + +var issue41621epilog = ` +} +func getLines() []string { + return lines +} +func main() { + println(getLines()) +} +` + +func TestIssue41621LargeNumberOfRelocations(t *testing.T) { + if testing.Short() || (buildcfg.GOARCH != "amd64") { + t.Skipf("Skipping large number of relocations test in short mode or on %s", buildcfg.GOARCH) + } + testenv.MustHaveGoBuild(t) + + tmpdir, err := os.MkdirTemp("", "lotsofrelocs") + if err != nil { + t.Fatalf("can't create temp directory: %v\n", err) + } + defer os.RemoveAll(tmpdir) + + // Emit testcase. + var w bytes.Buffer + fmt.Fprintf(&w, issue41621prolog) + for i := 0; i < 1048576+13; i++ { + fmt.Fprintf(&w, "\t\"%d\",\n", i) + } + fmt.Fprintf(&w, issue41621epilog) + err = os.WriteFile(tmpdir+"/large.go", w.Bytes(), 0666) + if err != nil { + t.Fatalf("can't write output: %v\n", err) + } + + // Emit go.mod + w.Reset() + fmt.Fprintf(&w, "module issue41621\n\ngo 1.12\n") + err = os.WriteFile(tmpdir+"/go.mod", w.Bytes(), 0666) + if err != nil { + t.Fatalf("can't write output: %v\n", err) + } + w.Reset() + + // Build. + cmd := testenv.Command(t, testenv.GoToolPath(t), "build", "-o", "large") + cmd.Dir = tmpdir + out, err := cmd.CombinedOutput() + if err != nil { + t.Fatalf("Build failed: %v, output: %s", err, out) + } +} |