/
reader.go
2800 lines (2312 loc) · 66.6 KB
/
reader.go
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// 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"
"internal/buildcfg"
"internal/pkgbits"
"strings"
"cmd/compile/internal/base"
"cmd/compile/internal/deadcode"
"cmd/compile/internal/dwarfgen"
"cmd/compile/internal/inline"
"cmd/compile/internal/ir"
"cmd/compile/internal/reflectdata"
"cmd/compile/internal/typecheck"
"cmd/compile/internal/types"
"cmd/internal/obj"
"cmd/internal/src"
)
// This file implements cmd/compile backend's reader for the Unified
// IR export data.
// A pkgReader reads Unified IR export data.
type pkgReader struct {
pkgbits.PkgDecoder
// Indices for encoded things; lazily populated as needed.
//
// Note: Objects (i.e., ir.Names) are lazily instantiated by
// populating their types.Sym.Def; see objReader below.
posBases []*src.PosBase
pkgs []*types.Pkg
typs []*types.Type
// offset for rewriting the given (absolute!) index into the output,
// but bitwise inverted so we can detect if we're missing the entry
// or not.
newindex []pkgbits.Index
}
func newPkgReader(pr pkgbits.PkgDecoder) *pkgReader {
return &pkgReader{
PkgDecoder: pr,
posBases: make([]*src.PosBase, pr.NumElems(pkgbits.RelocPosBase)),
pkgs: make([]*types.Pkg, pr.NumElems(pkgbits.RelocPkg)),
typs: make([]*types.Type, pr.NumElems(pkgbits.RelocType)),
newindex: make([]pkgbits.Index, pr.TotalElems()),
}
}
// A pkgReaderIndex compactly identifies an index (and its
// corresponding dictionary) within a package's export data.
type pkgReaderIndex struct {
pr *pkgReader
idx pkgbits.Index
dict *readerDict
}
func (pri pkgReaderIndex) asReader(k pkgbits.RelocKind, marker pkgbits.SyncMarker) *reader {
r := pri.pr.newReader(k, pri.idx, marker)
r.dict = pri.dict
return r
}
func (pr *pkgReader) newReader(k pkgbits.RelocKind, idx pkgbits.Index, marker pkgbits.SyncMarker) *reader {
return &reader{
Decoder: pr.NewDecoder(k, idx, marker),
p: pr,
}
}
// A writer provides APIs for reading an individual element.
type reader struct {
pkgbits.Decoder
p *pkgReader
dict *readerDict
// TODO(mdempsky): The state below is all specific to reading
// function bodies. It probably makes sense to split it out
// separately so that it doesn't take up space in every reader
// instance.
curfn *ir.Func
locals []*ir.Name
closureVars []*ir.Name
funarghack bool
// 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
}
type readerDict struct {
// targs holds the implicit and explicit type arguments in use for
// reading the current object. For example:
//
// func F[T any]() {
// type X[U any] struct { t T; u U }
// var _ X[string]
// }
//
// var _ = F[int]
//
// While instantiating F[int], we need to in turn instantiate
// X[string]. [int] and [string] are explicit type arguments for F
// and X, respectively; but [int] is also the implicit type
// arguments for X.
//
// (As an analogy to function literals, explicits are the function
// literal's formal parameters, while implicits are variables
// captured by the function literal.)
targs []*types.Type
// implicits counts how many of types within targs are implicit type
// arguments; the rest are explicit.
implicits int
derived []derivedInfo // reloc index of the derived type's descriptor
derivedTypes []*types.Type // slice of previously computed derived types
funcs []objInfo
funcsObj []ir.Node
itabs []itabInfo2
}
type itabInfo2 struct {
typ *types.Type
lsym *obj.LSym
}
func setType(n ir.Node, typ *types.Type) {
n.SetType(typ)
n.SetTypecheck(1)
}
func setValue(name *ir.Name, val constant.Value) {
name.SetVal(val)
name.Defn = nil
}
// @@@ Positions
// pos reads a position from the bitstream.
func (r *reader) pos() src.XPos {
return base.Ctxt.PosTable.XPos(r.pos0())
}
func (r *reader) pos0() src.Pos {
r.Sync(pkgbits.SyncPos)
if !r.Bool() {
return src.NoPos
}
posBase := r.posBase()
line := r.Uint()
col := r.Uint()
return src.MakePos(posBase, line, col)
}
// posBase reads a position base from the bitstream.
func (r *reader) posBase() *src.PosBase {
return r.inlPosBase(r.p.posBaseIdx(r.Reloc(pkgbits.RelocPosBase)))
}
// posBaseIdx returns the specified position base, reading it first if
// needed.
func (pr *pkgReader) posBaseIdx(idx pkgbits.Index) *src.PosBase {
if b := pr.posBases[idx]; b != nil {
return b
}
r := pr.newReader(pkgbits.RelocPosBase, idx, pkgbits.SyncPosBase)
var b *src.PosBase
absFilename := r.String()
filename := absFilename
// For build artifact stability, the export data format only
// contains the "absolute" filename as returned by objabi.AbsFile.
// However, some tests (e.g., test/run.go's asmcheck tests) expect
// to see the full, original filename printed out. Re-expanding
// "$GOROOT" to buildcfg.GOROOT is a close-enough approximation to
// satisfy this.
//
// TODO(mdempsky): De-duplicate this logic with similar logic in
// cmd/link/internal/ld's expandGoroot. However, this will probably
// require being more consistent about when we use native vs UNIX
// file paths.
const dollarGOROOT = "$GOROOT"
if buildcfg.GOROOT != "" && strings.HasPrefix(filename, dollarGOROOT) {
filename = buildcfg.GOROOT + filename[len(dollarGOROOT):]
}
if r.Bool() {
b = src.NewFileBase(filename, absFilename)
} else {
pos := r.pos0()
line := r.Uint()
col := r.Uint()
b = src.NewLinePragmaBase(pos, filename, absFilename, line, col)
}
pr.posBases[idx] = b
return b
}
// TODO(mdempsky): Document this.
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
}
// TODO(mdempsky): Document this.
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)
}
// @@@ Packages
// pkg reads a package reference from the bitstream.
func (r *reader) pkg() *types.Pkg {
r.Sync(pkgbits.SyncPkg)
return r.p.pkgIdx(r.Reloc(pkgbits.RelocPkg))
}
// pkgIdx returns the specified package from the export data, reading
// it first if needed.
func (pr *pkgReader) pkgIdx(idx pkgbits.Index) *types.Pkg {
if pkg := pr.pkgs[idx]; pkg != nil {
return pkg
}
pkg := pr.newReader(pkgbits.RelocPkg, idx, pkgbits.SyncPkgDef).doPkg()
pr.pkgs[idx] = pkg
return pkg
}
// doPkg reads a package definition from the bitstream.
func (r *reader) doPkg() *types.Pkg {
path := r.String()
switch path {
case "":
path = r.p.PkgPath()
case "builtin":
return types.BuiltinPkg
case "unsafe":
return types.UnsafePkg
}
name := r.String()
pkg := types.NewPkg(path, "")
if pkg.Name == "" {
pkg.Name = name
} else {
base.Assertf(pkg.Name == name, "package %q has name %q, but want %q", pkg.Path, pkg.Name, name)
}
return pkg
}
// @@@ Types
func (r *reader) typ() *types.Type {
return r.typWrapped(true)
}
// typWrapped is like typ, but allows suppressing generation of
// unnecessary wrappers as a compile-time optimization.
func (r *reader) typWrapped(wrapped bool) *types.Type {
return r.p.typIdx(r.typInfo(), r.dict, wrapped)
}
func (r *reader) typInfo() typeInfo {
r.Sync(pkgbits.SyncType)
if r.Bool() {
return typeInfo{idx: pkgbits.Index(r.Len()), derived: true}
}
return typeInfo{idx: r.Reloc(pkgbits.RelocType), derived: false}
}
func (pr *pkgReader) typIdx(info typeInfo, dict *readerDict, wrapped bool) *types.Type {
idx := info.idx
var where **types.Type
if info.derived {
where = &dict.derivedTypes[idx]
idx = dict.derived[idx].idx
} else {
where = &pr.typs[idx]
}
if typ := *where; typ != nil {
return typ
}
r := pr.newReader(pkgbits.RelocType, idx, pkgbits.SyncTypeIdx)
r.dict = dict
typ := r.doTyp()
assert(typ != nil)
// For recursive type declarations involving interfaces and aliases,
// above r.doTyp() call may have already set pr.typs[idx], so just
// double check and return the type.
//
// Example:
//
// type F = func(I)
//
// type I interface {
// m(F)
// }
//
// The writer writes data types in following index order:
//
// 0: func(I)
// 1: I
// 2: interface{m(func(I))}
//
// The reader resolves it in following index order:
//
// 0 -> 1 -> 2 -> 0 -> 1
//
// and can divide in logically 2 steps:
//
// - 0 -> 1 : first time the reader reach type I,
// it creates new named type with symbol I.
//
// - 2 -> 0 -> 1: the reader ends up reaching symbol I again,
// now the symbol I was setup in above step, so
// the reader just return the named type.
//
// Now, the functions called return, the pr.typs looks like below:
//
// - 0 -> 1 -> 2 -> 0 : [<T> I <T>]
// - 0 -> 1 -> 2 : [func(I) I <T>]
// - 0 -> 1 : [func(I) I interface { "".m(func("".I)) }]
//
// The idx 1, corresponding with type I was resolved successfully
// after r.doTyp() call.
if prev := *where; prev != nil {
return prev
}
if wrapped {
// Only cache if we're adding wrappers, so that other callers that
// find a cached type know it was wrapped.
*where = typ
r.needWrapper(typ)
}
if !typ.IsUntyped() {
types.CheckSize(typ)
}
return typ
}
func (r *reader) doTyp() *types.Type {
switch tag := pkgbits.CodeType(r.Code(pkgbits.SyncType)); tag {
default:
panic(fmt.Sprintf("unexpected type: %v", tag))
case pkgbits.TypeBasic:
return *basics[r.Len()]
case pkgbits.TypeNamed:
obj := r.obj()
assert(obj.Op() == ir.OTYPE)
return obj.Type()
case pkgbits.TypeTypeParam:
return r.dict.targs[r.Len()]
case pkgbits.TypeArray:
len := int64(r.Uint64())
return types.NewArray(r.typ(), len)
case pkgbits.TypeChan:
dir := dirs[r.Len()]
return types.NewChan(r.typ(), dir)
case pkgbits.TypeMap:
return types.NewMap(r.typ(), r.typ())
case pkgbits.TypePointer:
return types.NewPtr(r.typ())
case pkgbits.TypeSignature:
return r.signature(types.LocalPkg, nil)
case pkgbits.TypeSlice:
return types.NewSlice(r.typ())
case pkgbits.TypeStruct:
return r.structType()
case pkgbits.TypeInterface:
return r.interfaceType()
case pkgbits.TypeUnion:
return r.unionType()
}
}
func (r *reader) unionType() *types.Type {
terms := make([]*types.Type, r.Len())
tildes := make([]bool, len(terms))
for i := range terms {
tildes[i] = r.Bool()
terms[i] = r.typ()
}
return types.NewUnion(terms, tildes)
}
func (r *reader) interfaceType() *types.Type {
tpkg := types.LocalPkg // TODO(mdempsky): Remove after iexport is gone.
nmethods, nembeddeds := r.Len(), r.Len()
implicit := nmethods == 0 && nembeddeds == 1 && r.Bool()
assert(!implicit) // implicit interfaces only appear in constraints
fields := make([]*types.Field, nmethods+nembeddeds)
methods, embeddeds := fields[:nmethods], fields[nmethods:]
for i := range methods {
pos := r.pos()
pkg, sym := r.selector()
tpkg = pkg
mtyp := r.signature(pkg, types.FakeRecv())
methods[i] = types.NewField(pos, sym, mtyp)
}
for i := range embeddeds {
embeddeds[i] = types.NewField(src.NoXPos, nil, r.typ())
}
if len(fields) == 0 {
return types.Types[types.TINTER] // empty interface
}
return types.NewInterface(tpkg, fields, false)
}
func (r *reader) structType() *types.Type {
tpkg := types.LocalPkg // TODO(mdempsky): Remove after iexport is gone.
fields := make([]*types.Field, r.Len())
for i := range fields {
pos := r.pos()
pkg, sym := r.selector()
tpkg = pkg
ftyp := r.typ()
tag := r.String()
embedded := r.Bool()
f := types.NewField(pos, sym, ftyp)
f.Note = tag
if embedded {
f.Embedded = 1
}
fields[i] = f
}
return types.NewStruct(tpkg, fields)
}
func (r *reader) signature(tpkg *types.Pkg, recv *types.Field) *types.Type {
r.Sync(pkgbits.SyncSignature)
params := r.params(&tpkg)
results := r.params(&tpkg)
if r.Bool() { // variadic
params[len(params)-1].SetIsDDD(true)
}
return types.NewSignature(tpkg, recv, nil, params, results)
}
func (r *reader) params(tpkg **types.Pkg) []*types.Field {
r.Sync(pkgbits.SyncParams)
fields := make([]*types.Field, r.Len())
for i := range fields {
*tpkg, fields[i] = r.param()
}
return fields
}
func (r *reader) param() (*types.Pkg, *types.Field) {
r.Sync(pkgbits.SyncParam)
pos := r.pos()
pkg, sym := r.localIdent()
typ := r.typ()
return pkg, types.NewField(pos, sym, typ)
}
// @@@ Objects
// objReader maps qualified identifiers (represented as *types.Sym) to
// a pkgReader and corresponding index that can be used for reading
// that object's definition.
var objReader = map[*types.Sym]pkgReaderIndex{}
// obj reads an instantiated object reference from the bitstream.
func (r *reader) obj() ir.Node {
r.Sync(pkgbits.SyncObject)
if r.Bool() {
idx := r.Len()
obj := r.dict.funcsObj[idx]
if obj == nil {
fn := r.dict.funcs[idx]
targs := make([]*types.Type, len(fn.explicits))
for i, targ := range fn.explicits {
targs[i] = r.p.typIdx(targ, r.dict, true)
}
obj = r.p.objIdx(fn.idx, nil, targs)
assert(r.dict.funcsObj[idx] == nil)
r.dict.funcsObj[idx] = obj
}
return obj
}
idx := r.Reloc(pkgbits.RelocObj)
explicits := make([]*types.Type, r.Len())
for i := range explicits {
explicits[i] = r.typ()
}
var implicits []*types.Type
if r.dict != nil {
implicits = r.dict.targs
}
return r.p.objIdx(idx, implicits, explicits)
}
// objIdx returns the specified object from the bitstream,
// instantiated with the given type arguments, if any.
func (pr *pkgReader) objIdx(idx pkgbits.Index, implicits, explicits []*types.Type) ir.Node {
rname := pr.newReader(pkgbits.RelocName, idx, pkgbits.SyncObject1)
_, sym := rname.qualifiedIdent()
tag := pkgbits.CodeObj(rname.Code(pkgbits.SyncCodeObj))
if tag == pkgbits.ObjStub {
assert(!sym.IsBlank())
switch sym.Pkg {
case types.BuiltinPkg, types.UnsafePkg:
return sym.Def.(ir.Node)
}
if pri, ok := objReader[sym]; ok {
return pri.pr.objIdx(pri.idx, nil, explicits)
}
base.Fatalf("unresolved stub: %v", sym)
}
dict := pr.objDictIdx(sym, idx, implicits, explicits)
r := pr.newReader(pkgbits.RelocObj, idx, pkgbits.SyncObject1)
rext := pr.newReader(pkgbits.RelocObjExt, idx, pkgbits.SyncObject1)
r.dict = dict
rext.dict = dict
sym = r.mangle(sym)
if !sym.IsBlank() && sym.Def != nil {
return sym.Def.(*ir.Name)
}
do := func(op ir.Op, hasTParams bool) *ir.Name {
pos := r.pos()
setBasePos(pos)
if hasTParams {
r.typeParamNames()
}
name := ir.NewDeclNameAt(pos, op, sym)
name.Class = ir.PEXTERN // may be overridden later
if !sym.IsBlank() {
if sym.Def != nil {
base.FatalfAt(name.Pos(), "already have a definition for %v", name)
}
assert(sym.Def == nil)
sym.Def = name
}
return name
}
switch tag {
default:
panic("unexpected object")
case pkgbits.ObjAlias:
name := do(ir.OTYPE, false)
setType(name, r.typ())
name.SetAlias(true)
return name
case pkgbits.ObjConst:
name := do(ir.OLITERAL, false)
typ := r.typ()
val := FixValue(typ, r.Value())
setType(name, typ)
setValue(name, val)
return name
case pkgbits.ObjFunc:
if sym.Name == "init" {
sym = Renameinit()
}
name := do(ir.ONAME, true)
setType(name, r.signature(sym.Pkg, nil))
name.Func = ir.NewFunc(r.pos())
name.Func.Nname = name
if r.hasTypeParams() {
name.Func.SetDupok(true)
}
rext.funcExt(name)
return name
case pkgbits.ObjType:
name := do(ir.OTYPE, true)
typ := types.NewNamed(name)
setType(name, typ)
// Important: We need to do this before SetUnderlying.
rext.typeExt(name)
// We need to defer CheckSize until we've called SetUnderlying to
// handle recursive types.
types.DeferCheckSize()
typ.SetUnderlying(r.typWrapped(false))
types.ResumeCheckSize()
methods := make([]*types.Field, r.Len())
for i := range methods {
methods[i] = r.method(rext)
}
if len(methods) != 0 {
typ.Methods().Set(methods)
}
r.needWrapper(typ)
return name
case pkgbits.ObjVar:
name := do(ir.ONAME, false)
setType(name, r.typ())
rext.varExt(name)
return name
}
}
func (r *reader) mangle(sym *types.Sym) *types.Sym {
if !r.hasTypeParams() {
return sym
}
var buf bytes.Buffer
buf.WriteString(sym.Name)
buf.WriteByte('[')
for i, targ := range r.dict.targs {
if i > 0 {
if i == r.dict.implicits {
buf.WriteByte(';')
} else {
buf.WriteByte(',')
}
}
buf.WriteString(targ.LinkString())
}
buf.WriteByte(']')
return sym.Pkg.Lookup(buf.String())
}
// objDictIdx reads and returns the specified object dictionary.
func (pr *pkgReader) objDictIdx(sym *types.Sym, idx pkgbits.Index, implicits, explicits []*types.Type) *readerDict {
r := pr.newReader(pkgbits.RelocObjDict, idx, pkgbits.SyncObject1)
var dict readerDict
nimplicits := r.Len()
nexplicits := r.Len()
if nimplicits > len(implicits) || nexplicits != len(explicits) {
base.Fatalf("%v has %v+%v params, but instantiated with %v+%v args", sym, nimplicits, nexplicits, len(implicits), len(explicits))
}
dict.targs = append(implicits[:nimplicits:nimplicits], explicits...)
dict.implicits = nimplicits
// For stenciling, we can just skip over the type parameters.
for range dict.targs[dict.implicits:] {
// Skip past bounds without actually evaluating them.
r.Sync(pkgbits.SyncType)
if r.Bool() {
r.Len()
} else {
r.Reloc(pkgbits.RelocType)
}
}
dict.derived = make([]derivedInfo, r.Len())
dict.derivedTypes = make([]*types.Type, len(dict.derived))
for i := range dict.derived {
dict.derived[i] = derivedInfo{r.Reloc(pkgbits.RelocType), r.Bool()}
}
dict.funcs = make([]objInfo, r.Len())
dict.funcsObj = make([]ir.Node, len(dict.funcs))
for i := range dict.funcs {
objIdx := r.Reloc(pkgbits.RelocObj)
targs := make([]typeInfo, r.Len())
for j := range targs {
targs[j] = r.typInfo()
}
dict.funcs[i] = objInfo{idx: objIdx, explicits: targs}
}
dict.itabs = make([]itabInfo2, r.Len())
for i := range dict.itabs {
typ := pr.typIdx(typeInfo{idx: pkgbits.Index(r.Len()), derived: true}, &dict, true)
ifaceInfo := r.typInfo()
var lsym *obj.LSym
if typ.IsInterface() {
lsym = reflectdata.TypeLinksym(typ)
} else {
iface := pr.typIdx(ifaceInfo, &dict, true)
lsym = reflectdata.ITabLsym(typ, iface)
}
dict.itabs[i] = itabInfo2{typ: typ, lsym: lsym}
}
return &dict
}
func (r *reader) typeParamNames() {
r.Sync(pkgbits.SyncTypeParamNames)
for range r.dict.targs[r.dict.implicits:] {
r.pos()
r.localIdent()
}
}
func (r *reader) method(rext *reader) *types.Field {
r.Sync(pkgbits.SyncMethod)
pos := r.pos()
pkg, sym := r.selector()
r.typeParamNames()
_, recv := r.param()
typ := r.signature(pkg, recv)
fnsym := sym
fnsym = ir.MethodSym(recv.Type, fnsym)
name := ir.NewNameAt(pos, fnsym)
setType(name, typ)
name.Func = ir.NewFunc(r.pos())
name.Func.Nname = name
if r.hasTypeParams() {
name.Func.SetDupok(true)
}
rext.funcExt(name)
meth := types.NewField(name.Func.Pos(), sym, typ)
meth.Nname = name
meth.SetNointerface(name.Func.Pragma&ir.Nointerface != 0)
return meth
}
func (r *reader) qualifiedIdent() (pkg *types.Pkg, sym *types.Sym) {
r.Sync(pkgbits.SyncSym)
pkg = r.pkg()
if name := r.String(); name != "" {
sym = pkg.Lookup(name)
}
return
}
func (r *reader) localIdent() (pkg *types.Pkg, sym *types.Sym) {
r.Sync(pkgbits.SyncLocalIdent)
pkg = r.pkg()
if name := r.String(); name != "" {
sym = pkg.Lookup(name)
}
return
}
func (r *reader) selector() (origPkg *types.Pkg, sym *types.Sym) {
r.Sync(pkgbits.SyncSelector)
origPkg = r.pkg()
name := r.String()
pkg := origPkg
if types.IsExported(name) {
pkg = types.LocalPkg
}
sym = pkg.Lookup(name)
return
}
func (r *reader) hasTypeParams() bool {
return r.dict.hasTypeParams()
}
func (dict *readerDict) hasTypeParams() bool {
return dict != nil && len(dict.targs) != 0
}
// @@@ Compiler extensions
func (r *reader) funcExt(name *ir.Name) {
r.Sync(pkgbits.SyncFuncExt)
name.Class = 0 // so MarkFunc doesn't complain
ir.MarkFunc(name)
fn := name.Func
// XXX: Workaround because linker doesn't know how to copy Pos.
if !fn.Pos().IsKnown() {
fn.SetPos(name.Pos())
}
// Normally, we only compile local functions, which saves redundant compilation work.
// n.Defn is not nil for local functions, and is nil for imported function. But for
// generic functions, we might have an instantiation that no other package has seen before.
// So we need to be conservative and compile it again.
//
// That's why name.Defn is set here, so ir.VisitFuncsBottomUp can analyze function.
// TODO(mdempsky,cuonglm): find a cleaner way to handle this.
if name.Sym().Pkg == types.LocalPkg || r.hasTypeParams() {
name.Defn = fn
}
fn.Pragma = r.pragmaFlag()
r.linkname(name)
typecheck.Func(fn)
if r.Bool() {
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(pkgbits.SyncEOF)
}
func (r *reader) typeExt(name *ir.Name) {
r.Sync(pkgbits.SyncTypeExt)
typ := name.Type()
if r.hasTypeParams() {
// Set "RParams" (really type arguments here, not parameters) so
// this type is treated as "fully instantiated". This ensures the
// type descriptor is written out as DUPOK and method wrappers are
// generated even for imported types.
var targs []*types.Type
targs = append(targs, r.dict.targs...)
typ.SetRParams(targs)
}
name.SetPragma(r.pragmaFlag())
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(pkgbits.SyncVarExt)
r.linkname(name)
}
func (r *reader) linkname(name *ir.Name) {
assert(name.Op() == ir.ONAME)
r.Sync(pkgbits.SyncLinkname)
if idx := r.Int64(); idx >= 0 {
lsym := name.Linksym()
lsym.SymIdx = int32(idx)
lsym.Set(obj.AttrIndexed, true)
} else {
name.Sym().Linkname = r.String()
}
}
func (r *reader) pragmaFlag() ir.PragmaFlag {
r.Sync(pkgbits.SyncPragma)
return ir.PragmaFlag(r.Int())
}
// @@@ Function bodies
// bodyReader tracks where the serialized IR for a 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
// addBody reads a function body reference from the element bitstream,
// and associates it with fn.
func (r *reader) addBody(fn *ir.Func) {
pri := pkgReaderIndex{r.p, r.Reloc(pkgbits.RelocBody), r.dict}
bodyReader[fn] = pri
if fn.Nname.Defn == nil {
// Don't read in function body for imported functions.
// See comment in funcExt.
return
}
if r.curfn == nil {
todoBodies = append(todoBodies, fn)
return
}
pri.funcBody(fn)
}
func (pri pkgReaderIndex) funcBody(fn *ir.Func) {
r := pri.asReader(pkgbits.RelocBody, pkgbits.SyncFuncBody)
r.funcBody(fn)
}
// funcBody reads a function body definition from the element
// bitstream, and populates fn with it.
func (r *reader) funcBody(fn *ir.Func) {
r.curfn = fn
r.closureVars = fn.ClosureVars
ir.WithFunc(fn, func() {
r.funcargs(fn)