[dev.link] cmd/link: convert findfunctab to loader APIs

Convert the linker's findfunctab phase to use the new loader APIs.

Change-Id: Ia980a85963fe2e7c554c212c0cc89208272264bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/227842
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

diff --git a/src/cmd/link/internal/ld/main.go b/src/cmd/link/internal/ld/main.go
index 48f89c96d4dfed1b4c1b2c725b3d6aef3ad78d2f..182ebdf9d711a83bb45a20bf0f9251f5724a9b1d 100644 (file)
--- a/src/cmd/link/internal/ld/main.go
+++ b/src/cmd/link/internal/ld/main.go
@@ -295,11 +295,11 @@ func Main(arch *sys.Arch, theArch Arch) {
        bench.Start("buildinfo")
        ctxt.buildinfo()
        bench.Start("pclntab")
-       ctxt.pclntab()
+       container := ctxt.pclntab()
+       bench.Start("findfunctab")
+       ctxt.findfunctab(container)
        bench.Start("loadlibfull")
        ctxt.loadlibfull() // XXX do it here for now
-       bench.Start("findfunctab")
-       ctxt.findfunctab()
        bench.Start("symtab")
        ctxt.symtab()
        bench.Start("dodata")

diff --git a/src/cmd/link/internal/ld/pcln.go b/src/cmd/link/internal/ld/pcln.go
index c89ca602e7cdb099fa0ec150dedee0e6b8addd1c..8f1e0a423bcc2543e1cfe4d58af720e82e810c92 100644 (file)
--- a/src/cmd/link/internal/ld/pcln.go
+++ b/src/cmd/link/internal/ld/pcln.go
@@ -137,25 +137,13 @@ func onlycsymbol(sname string) bool {
        return false
 }
 
-func (state *pclnState) emitPcln(ctxt *Link, s loader.Sym) bool {
-       if ctxt.BuildMode == BuildModePlugin && ctxt.HeadType == objabi.Hdarwin && onlycsymbol(state.ldr.SymName(s)) {
+func emitPcln(ctxt *Link, s loader.Sym, container loader.Bitmap) bool {
+       if ctxt.BuildMode == BuildModePlugin && ctxt.HeadType == objabi.Hdarwin && onlycsymbol(ctxt.loader.SymName(s)) {
                return false
        }
        // We want to generate func table entries only for the "lowest
        // level" symbols, not containers of subsymbols.
-       return !state.container.Has(s)
-}
-
-func emitPcln(ctxt *Link, s *sym.Symbol) bool {
-       if s == nil {
-               return true
-       }
-       if ctxt.BuildMode == BuildModePlugin && ctxt.HeadType == objabi.Hdarwin && onlycsymbol(s.Name) {
-               return false
-       }
-       // We want to generate func table entries only for the "lowest level" symbols,
-       // not containers of subsymbols.
-       return !s.Attr.Container()
+       return !container.Has(s)
 }
 
 func (state *pclnState) computeDeferReturn(target *Target, s loader.Sym) uint32 {
@@ -251,7 +239,11 @@ var pclntabLastFunc *sym.Symbol
 var pclntabFirstFunc2 loader.Sym
 var pclntabLastFunc2 loader.Sym
 
-func (ctxt *Link) pclntab() {
+// pclntab generates the pcln table for the link output. Return value
+// is a bitmap indexed by global symbol that marks 'container' text
+// symbols, e.g. the set of all symbols X such that Outer(S) = X for
+// some other text symbol S.
+func (ctxt *Link) pclntab() loader.Bitmap {
        funcdataBytes := int64(0)
        ldr := ctxt.loader
        ftabsym := ldr.LookupOrCreateSym("runtime.pclntab", 0)
@@ -280,7 +272,7 @@ func (ctxt *Link) pclntab() {
        var nfunc int32
        prevSect := ldr.SymSect(ctxt.Textp2[0])
        for _, s := range ctxt.Textp2 {
-               if !state.emitPcln(ctxt, s) {
+               if !emitPcln(ctxt, s, state.container) {
                        continue
                }
                nfunc++
@@ -343,7 +335,7 @@ func (ctxt *Link) pclntab() {
        nfunc = 0 // repurpose nfunc as a running index
        prevFunc := ctxt.Textp2[0]
        for _, s := range ctxt.Textp2 {
-               if !state.emitPcln(ctxt, s) {
+               if !emitPcln(ctxt, s, state.container) {
                        continue
                }
 
@@ -546,6 +538,8 @@ func (ctxt *Link) pclntab() {
        if ctxt.Debugvlog != 0 {
                ctxt.Logf("pclntab=%d bytes, funcdata total %d bytes\n", ftab.Size(), funcdataBytes)
        }
+
+       return state.container
 }
 
 func gorootFinal() string {
@@ -573,16 +567,20 @@ const (
 
 // findfunctab generates a lookup table to quickly find the containing
 // function for a pc. See src/runtime/symtab.go:findfunc for details.
-func (ctxt *Link) findfunctab() {
-       t := ctxt.Syms.Lookup("runtime.findfunctab", 0)
-       t.Type = sym.SRODATA
-       t.Attr |= sym.AttrReachable
-       t.Attr |= sym.AttrLocal
+// 'container' is a bitmap indexed by global symbol holding whether
+// a given text symbols is a container (outer sym).
+func (ctxt *Link) findfunctab(container loader.Bitmap) {
+       ldr := ctxt.loader
+       tsym := ldr.LookupOrCreateSym("runtime.findfunctab", 0)
+       t := ldr.MakeSymbolUpdater(tsym)
+       t.SetType(sym.SRODATA)
+       ldr.SetAttrReachable(tsym, true)
+       ldr.SetAttrLocal(tsym, true)
 
        // find min and max address
-       min := ctxt.Textp[0].Value
-       lastp := ctxt.Textp[len(ctxt.Textp)-1]
-       max := lastp.Value + lastp.Size
+       min := ldr.SymValue(ctxt.Textp2[0])
+       lastp := ctxt.Textp2[len(ctxt.Textp2)-1]
+       max := ldr.SymValue(lastp) + ldr.SymSize(lastp)
 
        // for each subbucket, compute the minimum of all symbol indexes
        // that map to that subbucket.
@@ -593,23 +591,23 @@ func (ctxt *Link) findfunctab() {
                indexes[i] = NOIDX
        }
        idx := int32(0)
-       for i, s := range ctxt.Textp {
-               if !emitPcln(ctxt, s) {
+       for i, s := range ctxt.Textp2 {
+               if !emitPcln(ctxt, s, container) {
                        continue
                }
-               p := s.Value
-               var e *sym.Symbol
+               p := ldr.SymValue(s)
+               var e loader.Sym
                i++
-               if i < len(ctxt.Textp) {
-                       e = ctxt.Textp[i]
+               if i < len(ctxt.Textp2) {
+                       e = ctxt.Textp2[i]
                }
-               for !emitPcln(ctxt, e) && i < len(ctxt.Textp) {
-                       e = ctxt.Textp[i]
+               for !emitPcln(ctxt, e, container) && i < len(ctxt.Textp2) {
+                       e = ctxt.Textp2[i]
                        i++
                }
                q := max
-               if e != nil {
-                       q = e.Value
+               if e != 0 {
+                       q = ldr.SymValue(e)
                }
 
                //print("%d: [%lld %lld] %s\n", idx, p, q, s->name);