diff options
Diffstat (limited to 'src/cmd/internal/obj/plist.go')
| -rw-r--r-- | src/cmd/internal/obj/plist.go | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/src/cmd/internal/obj/plist.go b/src/cmd/internal/obj/plist.go new file mode 100644 index 0000000000..e55dbeca1e --- /dev/null +++ b/src/cmd/internal/obj/plist.go @@ -0,0 +1,218 @@ +// 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 obj + +import ( + "fmt" + "log" + "strings" +) + +type Plist struct { + Name *LSym + Firstpc *Prog + Recur int + Link *Plist +} + +/* + * start a new Prog list. + */ +func Linknewplist(ctxt *Link) *Plist { + pl := new(Plist) + if ctxt.Plist == nil { + ctxt.Plist = pl + } else { + ctxt.Plast.Link = pl + } + ctxt.Plast = pl + return pl +} + +func Flushplist(ctxt *Link) { + flushplist(ctxt, ctxt.Debugasm == 0) +} +func FlushplistNoFree(ctxt *Link) { + flushplist(ctxt, false) +} +func flushplist(ctxt *Link, freeProgs bool) { + // Build list of symbols, and assign instructions to lists. + // Ignore ctxt->plist boundaries. There are no guarantees there, + // and the assemblers just use one big list. + var curtext *LSym + var etext *Prog + var text []*LSym + + for pl := ctxt.Plist; pl != nil; pl = pl.Link { + var plink *Prog + for p := pl.Firstpc; p != nil; p = plink { + if ctxt.Debugasm != 0 && ctxt.Debugvlog != 0 { + fmt.Printf("obj: %v\n", p) + } + plink = p.Link + p.Link = nil + + switch p.As { + case AEND: + continue + + case ATYPE: + // Assume each TYPE instruction describes + // a different local variable or parameter, + // so no dedup. + // Using only the TYPE instructions means + // that we discard location information about local variables + // in C and assembly functions; that information is inferred + // from ordinary references, because there are no TYPE + // instructions there. Without the type information, gdb can't + // use the locations, so we don't bother to save them. + // If something else could use them, we could arrange to + // preserve them. + if curtext == nil { + continue + } + a := new(Auto) + a.Asym = p.From.Sym + a.Aoffset = int32(p.From.Offset) + a.Name = int16(p.From.Name) + a.Gotype = p.From.Gotype + a.Link = curtext.Autom + curtext.Autom = a + continue + + case AGLOBL: + s := p.From.Sym + if s.Seenglobl { + fmt.Printf("duplicate %v\n", p) + } + s.Seenglobl = true + if s.Onlist { + log.Fatalf("symbol %s listed multiple times", s.Name) + } + s.Onlist = true + ctxt.Data = append(ctxt.Data, s) + s.Size = p.To.Offset + if s.Type == 0 || s.Type == SXREF { + s.Type = SBSS + } + flag := int(p.From3.Offset) + if flag&DUPOK != 0 { + s.Dupok = true + } + if flag&RODATA != 0 { + s.Type = SRODATA + } else if flag&NOPTR != 0 { + s.Type = SNOPTRBSS + } else if flag&TLSBSS != 0 { + s.Type = STLSBSS + } + continue + + case ATEXT: + s := p.From.Sym + if s == nil { + // func _() { } + curtext = nil + + continue + } + + if s.Text != nil { + log.Fatalf("duplicate TEXT for %s", s.Name) + } + if s.Onlist { + log.Fatalf("symbol %s listed multiple times", s.Name) + } + s.Onlist = true + text = append(text, s) + flag := int(p.From3Offset()) + if flag&DUPOK != 0 { + s.Dupok = true + } + if flag&NOSPLIT != 0 { + s.Nosplit = true + } + if flag&REFLECTMETHOD != 0 { + s.ReflectMethod = true + } + s.Type = STEXT + s.Text = p + etext = p + curtext = s + continue + + case AFUNCDATA: + // Rewrite reference to go_args_stackmap(SB) to the Go-provided declaration information. + if curtext == nil { // func _() {} + continue + } + if p.To.Sym.Name == "go_args_stackmap" { + if p.From.Type != TYPE_CONST || p.From.Offset != FUNCDATA_ArgsPointerMaps { + ctxt.Diag("FUNCDATA use of go_args_stackmap(SB) without FUNCDATA_ArgsPointerMaps") + } + p.To.Sym = Linklookup(ctxt, fmt.Sprintf("%s.args_stackmap", curtext.Name), int(curtext.Version)) + } + + } + + if curtext == nil { + etext = nil + continue + } + etext.Link = p + etext = p + } + } + + // Add reference to Go arguments for C or assembly functions without them. + for _, s := range text { + if !strings.HasPrefix(s.Name, "\"\".") { + continue + } + found := false + var p *Prog + for p = s.Text; p != nil; p = p.Link { + if p.As == AFUNCDATA && p.From.Type == TYPE_CONST && p.From.Offset == FUNCDATA_ArgsPointerMaps { + found = true + break + } + } + + if !found { + p = Appendp(ctxt, s.Text) + p.As = AFUNCDATA + p.From.Type = TYPE_CONST + p.From.Offset = FUNCDATA_ArgsPointerMaps + p.To.Type = TYPE_MEM + p.To.Name = NAME_EXTERN + p.To.Sym = Linklookup(ctxt, fmt.Sprintf("%s.args_stackmap", s.Name), int(s.Version)) + } + } + + // Turn functions into machine code images. + for _, s := range text { + mkfwd(s) + linkpatch(ctxt, s) + if ctxt.Flag_optimize { + ctxt.Arch.Follow(ctxt, s) + } + ctxt.Arch.Preprocess(ctxt, s) + ctxt.Arch.Assemble(ctxt, s) + fieldtrack(ctxt, s) + linkpcln(ctxt, s) + if freeProgs { + s.Text = nil + } + } + + // Add to running list in ctxt. + ctxt.Text = append(ctxt.Text, text...) + ctxt.Plist = nil + ctxt.Plast = nil + ctxt.Curp = nil + if freeProgs { + ctxt.freeProgs() + } +} |