go parser 源码
golang parser 代码
文件路径：/src/go/internal/gccgoimporter/parser.go
// Copyright 2013 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 gccgoimporter
import (
"bytes"
"errors"
"fmt"
"go/constant"
"go/token"
"go/types"
"io"
"strconv"
"strings"
"text/scanner"
"unicode/utf8"
)
type parser struct {
scanner *scanner.Scanner
version string // format version
tok rune // current token
lit string // literal string; only valid for Ident, Int, String tokens
pkgpath string // package path of imported package
pkgname string // name of imported package
pkg *types.Package // reference to imported package
imports map[string]*types.Package // package path -> package object
typeList []types.Type // type number -> type
typeData []string // unparsed type data (v3 and later)
fixups []fixupRecord // fixups to apply at end of parsing
initdata InitData // package init priority data
aliases map[int]string // maps saved type number to alias name
}
// When reading export data it's possible to encounter a defined type
// N1 with an underlying defined type N2 while we are still reading in
// that defined type N2; see issues #29006 and #29198 for instances
// of this. Example:
//
// type N1 N2
// type N2 struct {
// ...
// p *N1
// }
//
// To handle such cases, the parser generates a fixup record (below) and
// delays setting of N1's underlying type until parsing is complete, at
// which point fixups are applied.
type fixupRecord struct {
toUpdate *types.Named // type to modify when fixup is processed
target types.Type // type that was incomplete when fixup was created
}
func (p *parser) init(filename string, src io.Reader, imports map[string]*types.Package) {
p.scanner = new(scanner.Scanner)
p.initScanner(filename, src)
p.imports = imports
p.aliases = make(map[int]string)
p.typeList = make([]types.Type, 1 /* type numbers start at 1 */, 16)
}
func (p *parser) initScanner(filename string, src io.Reader) {
p.scanner.Init(src)
p.scanner.Error = func(_ *scanner.Scanner, msg string) { p.error(msg) }
p.scanner.Mode = scanner.ScanIdents | scanner.ScanInts | scanner.ScanFloats | scanner.ScanStrings
p.scanner.Whitespace = 1<<'\t' | 1<<' '
p.scanner.Filename = filename // for good error messages
p.next()
}
type importError struct {
pos scanner.Position
err error
}
func (e importError) Error() string {
return fmt.Sprintf("import error %s (byte offset = %d): %s", e.pos, e.pos.Offset, e.err)
}
func (p *parser) error(err any) {
if s, ok := err.(string); ok {
err = errors.New(s)
}
// panic with a runtime.Error if err is not an error
panic(importError{p.scanner.Pos(), err.(error)})
}
func (p *parser) errorf(format string, args ...any) {
p.error(fmt.Errorf(format, args...))
}
func (p *parser) expect(tok rune) string {
lit := p.lit
if p.tok != tok {
p.errorf("expected %s, got %s (%s)", scanner.TokenString(tok), scanner.TokenString(p.tok), lit)
}
p.next()
return lit
}
func (p *parser) expectEOL() {
if p.version == "v1" || p.version == "v2" {
p.expect(';')
}
p.expect('\n')
}
func (p *parser) expectKeyword(keyword string) {
lit := p.expect(scanner.Ident)
if lit != keyword {
p.errorf("expected keyword %s, got %q", keyword, lit)
}
}
func (p *parser) parseString() string {
str, err := strconv.Unquote(p.expect(scanner.String))
if err != nil {
p.error(err)
}
return str
}
// unquotedString = { unquotedStringChar } .
// unquotedStringChar = <neither a whitespace nor a ';' char> .
func (p *parser) parseUnquotedString() string {
if p.tok == scanner.EOF {
p.error("unexpected EOF")
}
var buf bytes.Buffer
buf.WriteString(p.scanner.TokenText())
// This loop needs to examine each character before deciding whether to consume it. If we see a semicolon,
// we need to let it be consumed by p.next().
for ch := p.scanner.Peek(); ch != '\n' && ch != ';' && ch != scanner.EOF && p.scanner.Whitespace&(1<<uint(ch)) == 0; ch = p.scanner.Peek() {
buf.WriteRune(ch)
p.scanner.Next()
}
p.next()
return buf.String()
}
func (p *parser) next() {
p.tok = p.scanner.Scan()
switch p.tok {
case scanner.Ident, scanner.Int, scanner.Float, scanner.String, '·':
p.lit = p.scanner.TokenText()
default:
p.lit = ""
}
}
func (p *parser) parseQualifiedName() (path, name string) {
return p.parseQualifiedNameStr(p.parseString())
}
func (p *parser) parseUnquotedQualifiedName() (path, name string) {
return p.parseQualifiedNameStr(p.parseUnquotedString())
}
// qualifiedName = [ ["."] unquotedString "." ] unquotedString .
//
// The above production uses greedy matching.
func (p *parser) parseQualifiedNameStr(unquotedName string) (pkgpath, name string) {
parts := strings.Split(unquotedName, ".")
if parts[0] == "" {
parts = parts[1:]
}
switch len(parts) {
case 0:
p.errorf("malformed qualified name: %q", unquotedName)
case 1:
// unqualified name
pkgpath = p.pkgpath
name = parts[0]
default:
// qualified name, which may contain periods
pkgpath = strings.Join(parts[0:len(parts)-1], ".")
name = parts[len(parts)-1]
}
return
}
// getPkg returns the package for a given path. If the package is
// not found but we have a package name, create the package and
// add it to the p.imports map.
func (p *parser) getPkg(pkgpath, name string) *types.Package {
// package unsafe is not in the imports map - handle explicitly
if pkgpath == "unsafe" {
return types.Unsafe
}
pkg := p.imports[pkgpath]
if pkg == nil && name != "" {
pkg = types.NewPackage(pkgpath, name)
p.imports[pkgpath] = pkg
}
return pkg
}
// parseExportedName is like parseQualifiedName, but
// the package path is resolved to an imported *types.Package.
//
// ExportedName = string [string] .
func (p *parser) parseExportedName() (pkg *types.Package, name string) {
path, name := p.parseQualifiedName()
var pkgname string
if p.tok == scanner.String {
pkgname = p.parseString()
}
pkg = p.getPkg(path, pkgname)
if pkg == nil {
p.errorf("package %s (path = %q) not found", name, path)
}
return
}
// Name = QualifiedName | "?" .
func (p *parser) parseName() string {
if p.tok == '?' {
// Anonymous.
p.next()
return ""
}
// The package path is redundant for us. Don't try to parse it.
_, name := p.parseUnquotedQualifiedName()
return name
}
func deref(typ types.Type) types.Type {
if p, _ := typ.(*types.Pointer); p != nil {
typ = p.Elem()
}
return typ
}
// Field = Name Type [string] .
func (p *parser) parseField(pkg *types.Package) (field *types.Var, tag string) {
name := p.parseName()
typ, n := p.parseTypeExtended(pkg)
anon := false
if name == "" {
anon = true
// Alias?
if aname, ok := p.aliases[n]; ok {
name = aname
} else {
switch typ := deref(typ).(type) {
case *types.Basic:
name = typ.Name()
case *types.Named:
name = typ.Obj().Name()
default:
p.error("embedded field expected")
}
}
}
field = types.NewField(token.NoPos, pkg, name, typ, anon)
if p.tok == scanner.String {
tag = p.parseString()
}
return
}
// Param = Name ["..."] Type .
func (p *parser) parseParam(pkg *types.Package) (param *types.Var, isVariadic bool) {
name := p.parseName()
// Ignore names invented for inlinable functions.
if strings.HasPrefix(name, "p.") || strings.HasPrefix(name, "r.") || strings.HasPrefix(name, "$ret") {
name = ""
}
if p.tok == '<' && p.scanner.Peek() == 'e' {
// EscInfo = "<esc:" int ">" . (optional and ignored)
p.next()
p.expectKeyword("esc")
p.expect(':')
p.expect(scanner.Int)
p.expect('>')
}
if p.tok == '.' {
p.next()
p.expect('.')
p.expect('.')
isVariadic = true
}
typ := p.parseType(pkg)
if isVariadic {
typ = types.NewSlice(typ)
}
param = types.NewParam(token.NoPos, pkg, name, typ)
return
}
// Var = Name Type .
func (p *parser) parseVar(pkg *types.Package) *types.Var {
name := p.parseName()
v := types.NewVar(token.NoPos, pkg, name, p.parseType(pkg))
if name[0] == '.' || name[0] == '<' {
// This is an unexported variable,
// or a variable defined in a different package.
// We only want to record exported variables.
return nil
}
return v
}
// Conversion = "convert" "(" Type "," ConstValue ")" .
func (p *parser) parseConversion(pkg *types.Package) (val constant.Value, typ types.Type) {
p.expectKeyword("convert")
p.expect('(')
typ = p.parseType(pkg)
p.expect(',')
val, _ = p.parseConstValue(pkg)
p.expect(')')
return
}
// ConstValue = string | "false" | "true" | ["-"] (int ["'"] | FloatOrComplex) | Conversion .
// FloatOrComplex = float ["i" | ("+"|"-") float "i"] .
func (p *parser) parseConstValue(pkg *types.Package) (val constant.Value, typ types.Type) {
// v3 changed to $false, $true, $convert, to avoid confusion
// with variable names in inline function bodies.
if p.tok == '$' {
p.next()
if p.tok != scanner.Ident {
p.errorf("expected identifier after '$', got %s (%q)", scanner.TokenString(p.tok), p.lit)
}
}
switch p.tok {
case scanner.String:
str := p.parseString()
val = constant.MakeString(str)
typ = types.Typ[types.UntypedString]
return
case scanner.Ident:
b := false
switch p.lit {
case "false":
case "true":
b = true
case "convert":
return p.parseConversion(pkg)
default:
p.errorf("expected const value, got %s (%q)", scanner.TokenString(p.tok), p.lit)
}
p.next()
val = constant.MakeBool(b)
typ = types.Typ[types.UntypedBool]
return
}
sign := ""
if p.tok == '-' {
p.next()
sign = "-"
}
switch p.tok {
case scanner.Int:
val = constant.MakeFromLiteral(sign+p.lit, token.INT, 0)
if val == nil {
p.error("could not parse integer literal")
}
p.next()
if p.tok == '\'' {
p.next()
typ = types.Typ[types.UntypedRune]
} else {
typ = types.Typ[types.UntypedInt]
}
case scanner.Float:
re := sign + p.lit
p.next()
var im string
switch p.tok {
case '+':
p.next()
im = p.expect(scanner.Float)
case '-':
p.next()
im = "-" + p.expect(scanner.Float)
case scanner.Ident:
// re is in fact the imaginary component. Expect "i" below.
im = re
re = "0"
default:
val = constant.MakeFromLiteral(re, token.FLOAT, 0)
if val == nil {
p.error("could not parse float literal")
}
typ = types.Typ[types.UntypedFloat]
return
}
p.expectKeyword("i")
reval := constant.MakeFromLiteral(re, token.FLOAT, 0)
if reval == nil {
p.error("could not parse real component of complex literal")
}
imval := constant.MakeFromLiteral(im+"i", token.IMAG, 0)
if imval == nil {
p.error("could not parse imag component of complex literal")
}
val = constant.BinaryOp(reval, token.ADD, imval)
typ = types.Typ[types.UntypedComplex]
default:
p.errorf("expected const value, got %s (%q)", scanner.TokenString(p.tok), p.lit)
}
return
}
// Const = Name [Type] "=" ConstValue .
func (p *parser) parseConst(pkg *types.Package) *types.Const {
name := p.parseName()
var typ types.Type
if p.tok == '<' {
typ = p.parseType(pkg)
}
p.expect('=')
val, vtyp := p.parseConstValue(pkg)
if typ == nil {
typ = vtyp
}
return types.NewConst(token.NoPos, pkg, name, typ, val)
}
// reserved is a singleton type used to fill type map slots that have
// been reserved (i.e., for which a type number has been parsed) but
// which don't have their actual type yet. When the type map is updated,
// the actual type must replace a reserved entry (or we have an internal
// error). Used for self-verification only - not required for correctness.
var reserved = new(struct{ types.Type })
// reserve reserves the type map entry n for future use.
func (p *parser) reserve(n int) {
// Notes:
// - for pre-V3 export data, the type numbers we see are
// guaranteed to be in increasing order, so we append a
// reserved entry onto the list.
// - for V3+ export data, type numbers can appear in
// any order, however the 'types' section tells us the
// total number of types, hence typeList is pre-allocated.
if len(p.typeData) == 0 {
if n != len(p.typeList) {
p.errorf("invalid type number %d (out of sync)", n)
}
p.typeList = append(p.typeList, reserved)
} else {
if p.typeList[n] != nil {
p.errorf("previously visited type number %d", n)
}
p.typeList[n] = reserved
}
}
// update sets the type map entries for the entries in nlist to t.
// An entry in nlist can be a type number in p.typeList,
// used to resolve named types, or it can be a *types.Pointer,
// used to resolve pointers to named types in case they are referenced
// by embedded fields.
func (p *parser) update(t types.Type, nlist []any) {
if t == reserved {
p.errorf("internal error: update(%v) invoked on reserved", nlist)
}
if t == nil {
p.errorf("internal error: update(%v) invoked on nil", nlist)
}
for _, n := range nlist {
switch n := n.(type) {
case int:
if p.typeList[n] == t {
continue
}
if p.typeList[n] != reserved {
p.errorf("internal error: update(%v): %d not reserved", nlist, n)
}
p.typeList[n] = t
case *types.Pointer:
if *n != (types.Pointer{}) {
elem := n.Elem()
if elem == t {
continue
}
p.errorf("internal error: update: pointer already set to %v, expected %v", elem, t)
}
*n = *types.NewPointer(t)
default:
p.errorf("internal error: %T on nlist", n)
}
}
}
// NamedType = TypeName [ "=" ] Type { Method } .
// TypeName = ExportedName .
// Method = "func" "(" Param ")" Name ParamList ResultList [InlineBody] ";" .
func (p *parser) parseNamedType(nlist []any) types.Type {
pkg, name := p.parseExportedName()
scope := pkg.Scope()
obj := scope.Lookup(name)
if obj != nil && obj.Type() == nil {
p.errorf("%v has nil type", obj)
}
if p.tok == scanner.Ident && p.lit == "notinheap" {
p.next()
// The go/types package has no way of recording that
// this type is marked notinheap. Presumably no user
// of this package actually cares.
}
// type alias
if p.tok == '=' {
p.next()
p.aliases[nlist[len(nlist)-1].(int)] = name
if obj != nil {
// use the previously imported (canonical) type
t := obj.Type()
p.update(t, nlist)
p.parseType(pkg) // discard
return t
}
t := p.parseType(pkg, nlist...)
obj = types.NewTypeName(token.NoPos, pkg, name, t)
scope.Insert(obj)
return t
}
// defined type
if obj == nil {
// A named type may be referred to before the underlying type
// is known - set it up.
tname := types.NewTypeName(token.NoPos, pkg, name, nil)
types.NewNamed(tname, nil, nil)
scope.Insert(tname)
obj = tname
}
// use the previously imported (canonical), or newly created type
t := obj.Type()
p.update(t, nlist)
nt, ok := t.(*types.Named)
if !ok {
// This can happen for unsafe.Pointer, which is a TypeName holding a Basic type.
pt := p.parseType(pkg)
if pt != t {
p.error("unexpected underlying type for non-named TypeName")
}
return t
}
underlying := p.parseType(pkg)
if nt.Underlying() == nil {
if underlying.Underlying() == nil {
fix := fixupRecord{toUpdate: nt, target: underlying}
p.fixups = append(p.fixups, fix)
} else {
nt.SetUnderlying(underlying.Underlying())
}
}
if p.tok == '\n' {
p.next()
// collect associated methods
for p.tok == scanner.Ident {
p.expectKeyword("func")
if p.tok == '/' {
// Skip a /*nointerface*/ or /*asm ID */ comment.
p.expect('/')
p.expect('*')
if p.expect(scanner.Ident) == "asm" {
p.parseUnquotedString()
}
p.expect('*')
p.expect('/')
}
p.expect('(')
receiver, _ := p.parseParam(pkg)
p.expect(')')
name := p.parseName()
params, isVariadic := p.parseParamList(pkg)
results := p.parseResultList(pkg)
p.skipInlineBody()
p.expectEOL()
sig := types.NewSignatureType(receiver, nil, nil, params, results, isVariadic)
nt.AddMethod(types.NewFunc(token.NoPos, pkg, name, sig))
}
}
return nt
}
func (p *parser) parseInt64() int64 {
lit := p.expect(scanner.Int)
n, err := strconv.ParseInt(lit, 10, 64)
if err != nil {
p.error(err)
}
return n
}
func (p *parser) parseInt() int {
lit := p.expect(scanner.Int)
n, err := strconv.ParseInt(lit, 10, 0 /* int */)
if err != nil {
p.error(err)
}
return int(n)
}
// ArrayOrSliceType = "[" [ int ] "]" Type .
func (p *parser) parseArrayOrSliceType(pkg *types.Package, nlist []any) types.Type {
p.expect('[')
if p.tok == ']' {
p.next()
t := new(types.Slice)
p.update(t, nlist)
*t = *types.NewSlice(p.parseType(pkg))
return t
}
t := new(types.Array)
p.update(t, nlist)
len := p.parseInt64()
p.expect(']')
*t = *types.NewArray(p.parseType(pkg), len)
return t
}
// MapType = "map" "[" Type "]" Type .
func (p *parser) parseMapType(pkg *types.Package, nlist []any) types.Type {
p.expectKeyword("map")
t := new(types.Map)
p.update(t, nlist)
p.expect('[')
key := p.parseType(pkg)
p.expect(']')
elem := p.parseType(pkg)
*t = *types.NewMap(key, elem)
return t
}
// ChanType = "chan" ["<-" | "-<"] Type .
func (p *parser) parseChanType(pkg *types.Package, nlist []any) types.Type {
p.expectKeyword("chan")
t := new(types.Chan)
p.update(t, nlist)
dir := types.SendRecv
switch p.tok {
case '-':
p.next()
p.expect('<')
dir = types.SendOnly
case '<':
// don't consume '<' if it belongs to Type
if p.scanner.Peek() == '-' {
p.next()
p.expect('-')
dir = types.RecvOnly
}
}
*t = *types.NewChan(dir, p.parseType(pkg))
return t
}
// StructType = "struct" "{" { Field } "}" .
func (p *parser) parseStructType(pkg *types.Package, nlist []any) types.Type {
p.expectKeyword("struct")
t := new(types.Struct)
p.update(t, nlist)
var fields []*types.Var
var tags []string
p.expect('{')
for p.tok != '}' && p.tok != scanner.EOF {
field, tag := p.parseField(pkg)
p.expect(';')
fields = append(fields, field)
tags = append(tags, tag)
}
p.expect('}')
*t = *types.NewStruct(fields, tags)
return t
}
// ParamList = "(" [ { Parameter "," } Parameter ] ")" .
func (p *parser) parseParamList(pkg *types.Package) (*types.Tuple, bool) {
var list []*types.Var
isVariadic := false
p.expect('(')
for p.tok != ')' && p.tok != scanner.EOF {
if len(list) > 0 {
p.expect(',')
}
par, variadic := p.parseParam(pkg)
list = append(list, par)
if variadic {
if isVariadic {
p.error("... not on final argument")
}
isVariadic = true
}
}
p.expect(')')
return types.NewTuple(list...), isVariadic
}
// ResultList = Type | ParamList .
func (p *parser) parseResultList(pkg *types.Package) *types.Tuple {
switch p.tok {
case '<':
p.next()
if p.tok == scanner.Ident && p.lit == "inl" {
return nil
}
taa, _ := p.parseTypeAfterAngle(pkg)
return types.NewTuple(types.NewParam(token.NoPos, pkg, "", taa))
case '(':
params, _ := p.parseParamList(pkg)
return params
default:
return nil
}
}
// FunctionType = ParamList ResultList .
func (p *parser) parseFunctionType(pkg *types.Package, nlist []any) *types.Signature {
t := new(types.Signature)
p.update(t, nlist)
params, isVariadic := p.parseParamList(pkg)
results := p.parseResultList(pkg)
*t = *types.NewSignatureType(nil, nil, nil, params, results, isVariadic)
return t
}
// Func = Name FunctionType [InlineBody] .
func (p *parser) parseFunc(pkg *types.Package) *types.Func {
if p.tok == '/' {
// Skip an /*asm ID */ comment.
p.expect('/')
p.expect('*')
if p.expect(scanner.Ident) == "asm" {
p.parseUnquotedString()
}
p.expect('*')
p.expect('/')
}
name := p.parseName()
f := types.NewFunc(token.NoPos, pkg, name, p.parseFunctionType(pkg, nil))
p.skipInlineBody()
if name[0] == '.' || name[0] == '<' || strings.ContainsRune(name, '$') {
// This is an unexported function,
// or a function defined in a different package,
// or a type$equal or type$hash function.
// We only want to record exported functions.
return nil
}
return f
}
// InterfaceType = "interface" "{" { ("?" Type | Func) ";" } "}" .
func (p *parser) parseInterfaceType(pkg *types.Package, nlist []any) types.Type {
p.expectKeyword("interface")
t := new(types.Interface)
p.update(t, nlist)
var methods []*types.Func
var embeddeds []types.Type
p.expect('{')
for p.tok != '}' && p.tok != scanner.EOF {
if p.tok == '?' {
p.next()
embeddeds = append(embeddeds, p.parseType(pkg))
} else {
method := p.parseFunc(pkg)
if method != nil {
methods = append(methods, method)
}
}
p.expect(';')
}
p.expect('}')
*t = *types.NewInterfaceType(methods, embeddeds)
return t
}
// PointerType = "*" ("any" | Type) .
func (p *parser) parsePointerType(pkg *types.Package, nlist []any) types.Type {
p.expect('*')
if p.tok == scanner.Ident {
p.expectKeyword("any")
t := types.Typ[types.UnsafePointer]
p.update(t, nlist)
return t
}
t := new(types.Pointer)
p.update(t, nlist)
*t = *types.NewPointer(p.parseType(pkg, t))
return t
}
// TypeSpec = NamedType | MapType | ChanType | StructType | InterfaceType | PointerType | ArrayOrSliceType | FunctionType .
func (p *parser) parseTypeSpec(pkg *types.Package, nlist []any) types.Type {
switch p.tok {
case scanner.String:
return p.parseNamedType(nlist)
case scanner.Ident:
switch p.lit {
case "map":
return p.parseMapType(pkg, nlist)
case "chan":
return p.parseChanType(pkg, nlist)
case "struct":
return p.parseStructType(pkg, nlist)
case "interface":
return p.parseInterfaceType(pkg, nlist)
}
case '*':
return p.parsePointerType(pkg, nlist)
case '[':
return p.parseArrayOrSliceType(pkg, nlist)
case '(':
return p.parseFunctionType(pkg, nlist)
}
p.errorf("expected type name or literal, got %s", scanner.TokenString(p.tok))
return nil
}
const (
// From gofrontend/go/export.h
// Note that these values are negative in the gofrontend and have been made positive
// in the gccgoimporter.
gccgoBuiltinINT8 = 1
gccgoBuiltinINT16 = 2
gccgoBuiltinINT32 = 3
gccgoBuiltinINT64 = 4
gccgoBuiltinUINT8 = 5
gccgoBuiltinUINT16 = 6
gccgoBuiltinUINT32 = 7
gccgoBuiltinUINT64 = 8
gccgoBuiltinFLOAT32 = 9
gccgoBuiltinFLOAT64 = 10
gccgoBuiltinINT = 11
gccgoBuiltinUINT = 12
gccgoBuiltinUINTPTR = 13
gccgoBuiltinBOOL = 15
gccgoBuiltinSTRING = 16
gccgoBuiltinCOMPLEX64 = 17
gccgoBuiltinCOMPLEX128 = 18
gccgoBuiltinERROR = 19
gccgoBuiltinBYTE = 20
gccgoBuiltinRUNE = 21
)
func lookupBuiltinType(typ int) types.Type {
return [...]types.Type{
gccgoBuiltinINT8: types.Typ[types.Int8],
gccgoBuiltinINT16: types.Typ[types.Int16],
gccgoBuiltinINT32: types.Typ[types.Int32],
gccgoBuiltinINT64: types.Typ[types.Int64],
gccgoBuiltinUINT8: types.Typ[types.Uint8],
gccgoBuiltinUINT16: types.Typ[types.Uint16],
gccgoBuiltinUINT32: types.Typ[types.Uint32],
gccgoBuiltinUINT64: types.Typ[types.Uint64],
gccgoBuiltinFLOAT32: types.Typ[types.Float32],
gccgoBuiltinFLOAT64: types.Typ[types.Float64],
gccgoBuiltinINT: types.Typ[types.Int],
gccgoBuiltinUINT: types.Typ[types.Uint],
gccgoBuiltinUINTPTR: types.Typ[types.Uintptr],
gccgoBuiltinBOOL: types.Typ[types.Bool],
gccgoBuiltinSTRING: types.Typ[types.String],
gccgoBuiltinCOMPLEX64: types.Typ[types.Complex64],
gccgoBuiltinCOMPLEX128: types.Typ[types.Complex128],
gccgoBuiltinERROR: types.Universe.Lookup("error").Type(),
gccgoBuiltinBYTE: types.Universe.Lookup("byte").Type(),
gccgoBuiltinRUNE: types.Universe.Lookup("rune").Type(),
}[typ]
}
// Type = "<" "type" ( "-" int | int [ TypeSpec ] ) ">" .
//
// parseType updates the type map to t for all type numbers n.
func (p *parser) parseType(pkg *types.Package, n ...any) types.Type {
p.expect('<')
t, _ := p.parseTypeAfterAngle(pkg, n...)
return t
}
// (*parser).Type after reading the "<".
func (p *parser) parseTypeAfterAngle(pkg *types.Package, n ...any) (t types.Type, n1 int) {
p.expectKeyword("type")
n1 = 0
switch p.tok {
case scanner.Int:
n1 = p.parseInt()
if p.tok == '>' {
if len(p.typeData) > 0 && p.typeList[n1] == nil {
p.parseSavedType(pkg, n1, n)
}
t = p.typeList[n1]
if len(p.typeData) == 0 && t == reserved {
p.errorf("invalid type cycle, type %d not yet defined (nlist=%v)", n1, n)
}
p.update(t, n)
} else {
p.reserve(n1)
t = p.parseTypeSpec(pkg, append(n, n1))
}
case '-':
p.next()
n1 := p.parseInt()
t = lookupBuiltinType(n1)
p.update(t, n)
default:
p.errorf("expected type number, got %s (%q)", scanner.TokenString(p.tok), p.lit)
return nil, 0
}
if t == nil || t == reserved {
p.errorf("internal error: bad return from parseType(%v)", n)
}
p.expect('>')
return
}
// parseTypeExtended is identical to parseType, but if the type in
// question is a saved type, returns the index as well as the type
// pointer (index returned is zero if we parsed a builtin).
func (p *parser) parseTypeExtended(pkg *types.Package, n ...any) (t types.Type, n1 int) {
p.expect('<')
t, n1 = p.parseTypeAfterAngle(pkg, n...)
return
}
// InlineBody = "<inl:NN>" .{NN}
// Reports whether a body was skipped.
func (p *parser) skipInlineBody() {
// We may or may not have seen the '<' already, depending on
// whether the function had a result type or not.
if p.tok == '<' {
p.next()
p.expectKeyword("inl")
} else if p.tok != scanner.Ident || p.lit != "inl" {
return
} else {
p.next()
}
p.expect(':')
want := p.parseInt()
p.expect('>')
defer func(w uint64) {
p.scanner.Whitespace = w
}(p.scanner.Whitespace)
p.scanner.Whitespace = 0
got := 0
for got < want {
r := p.scanner.Next()
if r == scanner.EOF {
p.error("unexpected EOF")
}
got += utf8.RuneLen(r)
}
}
// Types = "types" maxp1 exportedp1 (offset length)* .
func (p *parser) parseTypes(pkg *types.Package) {
maxp1 := p.parseInt()
exportedp1 := p.parseInt()
p.typeList = make([]types.Type, maxp1, maxp1)
type typeOffset struct {
offset int
length int
}
var typeOffsets []typeOffset
total := 0
for i := 1; i < maxp1; i++ {
len := p.parseInt()
typeOffsets = append(typeOffsets, typeOffset{total, len})
total += len
}
defer func(w uint64) {
p.scanner.Whitespace = w
}(p.scanner.Whitespace)
p.scanner.Whitespace = 0
// We should now have p.tok pointing to the final newline.
// The next runes from the scanner should be the type data.
var sb strings.Builder
for sb.Len() < total {
r := p.scanner.Next()
if r == scanner.EOF {
p.error("unexpected EOF")
}
sb.WriteRune(r)
}
allTypeData := sb.String()
p.typeData = []string{""} // type 0, unused
for _, to := range typeOffsets {
p.typeData = append(p.typeData, allTypeData[to.offset:to.offset+to.length])
}
for i := 1; i < int(exportedp1); i++ {
p.parseSavedType(pkg, i, nil)
}
}
// parseSavedType parses one saved type definition.
func (p *parser) parseSavedType(pkg *types.Package, i int, nlist []any) {
defer func(s *scanner.Scanner, tok rune, lit string) {
p.scanner = s
p.tok = tok
p.lit = lit
}(p.scanner, p.tok, p.lit)
p.scanner = new(scanner.Scanner)
p.initScanner(p.scanner.Filename, strings.NewReader(p.typeData[i]))
p.expectKeyword("type")
id := p.parseInt()
if id != i {
p.errorf("type ID mismatch: got %d, want %d", id, i)
}
if p.typeList[i] == reserved {
p.errorf("internal error: %d already reserved in parseSavedType", i)
}
if p.typeList[i] == nil {
p.reserve(i)
p.parseTypeSpec(pkg, append(nlist, i))
}
if p.typeList[i] == nil || p.typeList[i] == reserved {
p.errorf("internal error: parseSavedType(%d,%v) reserved/nil", i, nlist)
}
}
// PackageInit = unquotedString unquotedString int .
func (p *parser) parsePackageInit() PackageInit {
name := p.parseUnquotedString()
initfunc := p.parseUnquotedString()
priority := -1
if p.version == "v1" {
priority = p.parseInt()
}
return PackageInit{Name: name, InitFunc: initfunc, Priority: priority}
}
// Create the package if we have parsed both the package path and package name.
func (p *parser) maybeCreatePackage() {
if p.pkgname != "" && p.pkgpath != "" {
p.pkg = p.getPkg(p.pkgpath, p.pkgname)
}
}
// InitDataDirective = ( "v1" | "v2" | "v3" ) ";" |
//
// "priority" int ";" |
// "init" { PackageInit } ";" |
// "checksum" unquotedString ";" .
func (p *parser) parseInitDataDirective() {
if p.tok != scanner.Ident {
// unexpected token kind; panic
p.expect(scanner.Ident)
}
switch p.lit {
case "v1", "v2", "v3":
p.version = p.lit
p.next()
p.expect(';')
p.expect('\n')
case "priority":
p.next()
p.initdata.Priority = p.parseInt()
p.expectEOL()
case "init":
p.next()
for p.tok != '\n' && p.tok != ';' && p.tok != scanner.EOF {
p.initdata.Inits = append(p.initdata.Inits, p.parsePackageInit())
}
p.expectEOL()
case "init_graph":
p.next()
// The graph data is thrown away for now.
for p.tok != '\n' && p.tok != ';' && p.tok != scanner.EOF {
p.parseInt64()
p.parseInt64()
}
p.expectEOL()
case "checksum":
// Don't let the scanner try to parse the checksum as a number.
defer func(mode uint) {
p.scanner.Mode = mode
}(p.scanner.Mode)
p.scanner.Mode &^= scanner.ScanInts | scanner.ScanFloats
p.next()
p.parseUnquotedString()
p.expectEOL()
default:
p.errorf("unexpected identifier: %q", p.lit)
}
}
// Directive = InitDataDirective |
//
// "package" unquotedString [ unquotedString ] [ unquotedString ] ";" |
// "pkgpath" unquotedString ";" |
// "prefix" unquotedString ";" |
// "import" unquotedString unquotedString string ";" |
// "indirectimport" unquotedString unquotedstring ";" |
// "func" Func ";" |
// "type" Type ";" |
// "var" Var ";" |
// "const" Const ";" .
func (p *parser) parseDirective() {
if p.tok != scanner.Ident {
// unexpected token kind; panic
p.expect(scanner.Ident)
}
switch p.lit {
case "v1", "v2", "v3", "priority", "init", "init_graph", "checksum":
p.parseInitDataDirective()
case "package":
p.next()
p.pkgname = p.parseUnquotedString()
p.maybeCreatePackage()
if p.version != "v1" && p.tok != '\n' && p.tok != ';' {
p.parseUnquotedString()
p.parseUnquotedString()
}
p.expectEOL()
case "pkgpath":
p.next()
p.pkgpath = p.parseUnquotedString()
p.maybeCreatePackage()
p.expectEOL()
case "prefix":
p.next()
p.pkgpath = p.parseUnquotedString()
p.expectEOL()
case "import":
p.next()
pkgname := p.parseUnquotedString()
pkgpath := p.parseUnquotedString()
p.getPkg(pkgpath, pkgname)
p.parseString()
p.expectEOL()
case "indirectimport":
p.next()
pkgname := p.parseUnquotedString()
pkgpath := p.parseUnquotedString()
p.getPkg(pkgpath, pkgname)
p.expectEOL()
case "types":
p.next()
p.parseTypes(p.pkg)
p.expectEOL()
case "func":
p.next()
fun := p.parseFunc(p.pkg)
if fun != nil {
p.pkg.Scope().Insert(fun)
}
p.expectEOL()
case "type":
p.next()
p.parseType(p.pkg)
p.expectEOL()
case "var":
p.next()
v := p.parseVar(p.pkg)
if v != nil {
p.pkg.Scope().Insert(v)
}
p.expectEOL()
case "const":
p.next()
c := p.parseConst(p.pkg)
p.pkg.Scope().Insert(c)
p.expectEOL()
default:
p.errorf("unexpected identifier: %q", p.lit)
}
}
// Package = { Directive } .
func (p *parser) parsePackage() *types.Package {
for p.tok != scanner.EOF {
p.parseDirective()
}
for _, f := range p.fixups {
if f.target.Underlying() == nil {
p.errorf("internal error: fixup can't be applied, loop required")
}
f.toUpdate.SetUnderlying(f.target.Underlying())
}
p.fixups = nil
for _, typ := range p.typeList {
if it, ok := typ.(*types.Interface); ok {
it.Complete()
}
}
p.pkg.MarkComplete()
return p.pkg
}
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