[dev.link] cmd/link: run setArchSyms earlier
Add some new loader.Sym equivalents to the archSyms struct so that we
can run setArchSyms earlier in the pipeline, and add a "mode" to
setArchSyms to control whether it should create loader.Sym symbols or
their *sym.Symbol equivalents.
These change needed for a subsequent patch in which addexport() is run
earlier as well
Change-Id: I0475c9388c39f13e045dd4aa9c90eaec42624810
Reviewed-on: https://go-review.googlesource.com/c/go/+/226361
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/lib.go b/src/cmd/link/internal/ld/lib.go
index 2661827..692cf4f 100644
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -126,6 +126,14 @@
// ----- loader.Sym equivalents -----
+ Rel2 loader.Sym
+ Rela2 loader.Sym
+ RelPLT2 loader.Sym
+ RelaPLT2 loader.Sym
+
+ LinkEditGOT2 loader.Sym
+ LinkEditPLT2 loader.Sym
+
TOC2 loader.Sym
DotTOC2 []loader.Sym // for each version
@@ -140,45 +148,71 @@
DynStr2 loader.Sym
}
-// setArchSyms sets up the ArchSyms structure, and must be called before
-// relocations are applied.
-func (ctxt *Link) setArchSyms() {
- ctxt.GOT2 = ctxt.loader.LookupOrCreateSym(".got", 0)
- ctxt.GOT = ctxt.loader.Syms[ctxt.GOT2]
- ctxt.PLT2 = ctxt.loader.LookupOrCreateSym(".plt", 0)
- ctxt.PLT = ctxt.loader.Syms[ctxt.PLT2]
- ctxt.GOTPLT2 = ctxt.loader.LookupOrCreateSym(".got.plt", 0)
- ctxt.GOTPLT = ctxt.loader.Syms[ctxt.GOTPLT2]
+const BeforeLoadlibFull = 1
+const AfterLoadlibFull = 2
- ctxt.Dynamic2 = ctxt.loader.LookupOrCreateSym(".dynamic", 0)
- ctxt.Dynamic = ctxt.loader.Syms[ctxt.Dynamic2]
- ctxt.DynSym2 = ctxt.loader.LookupOrCreateSym(".dynsym", 0)
- ctxt.DynSym = ctxt.loader.Syms[ctxt.DynSym2]
- ctxt.DynStr2 = ctxt.loader.LookupOrCreateSym(".dynstr", 0)
- ctxt.DynStr = ctxt.loader.Syms[ctxt.DynStr2]
+func (ctxt *Link) mkArchSym(which int, name string, ls *loader.Sym, ss **sym.Symbol) {
+ if which == BeforeLoadlibFull {
+ *ls = ctxt.loader.LookupOrCreateSym(name, 0)
+ } else {
+ *ss = ctxt.loader.Syms[*ls]
+ }
+}
+
+func (ctxt *Link) mkArchSymVec(which int, name string, i int, ls []loader.Sym, ss []*sym.Symbol) {
+ if which == BeforeLoadlibFull {
+ ls[i] = ctxt.loader.LookupOrCreateSym(name, 0)
+ } else {
+ ss[i] = ctxt.loader.Syms[ls[i]]
+ }
+}
+
+// setArchSyms sets up the ArchSyms structure, and must be called before
+// relocations are applied. This function is invoked twice, once prior
+// to loadlibfull(), and once after the work of loadlibfull is complete.
+func (ctxt *Link) setArchSyms(which int) {
+ if which != BeforeLoadlibFull && which != AfterLoadlibFull {
+ panic("internal error")
+ }
+ ctxt.mkArchSym(which, ".got", &ctxt.GOT2, &ctxt.GOT)
+ ctxt.mkArchSym(which, ".plt", &ctxt.PLT2, &ctxt.PLT)
+ ctxt.mkArchSym(which, ".got.plt", &ctxt.GOTPLT2, &ctxt.GOTPLT)
+ ctxt.mkArchSym(which, ".dynamic", &ctxt.Dynamic2, &ctxt.Dynamic)
+ ctxt.mkArchSym(which, ".dynsym", &ctxt.DynSym2, &ctxt.DynSym)
+ ctxt.mkArchSym(which, ".dynstr", &ctxt.DynStr2, &ctxt.DynStr)
if ctxt.IsAIX() {
- ctxt.TOC2 = ctxt.loader.LookupOrCreateSym("TOC", 0)
- ctxt.TOC = ctxt.loader.Syms[ctxt.TOC2]
- ctxt.DotTOC = make([]*sym.Symbol, ctxt.Syms.MaxVersion()+1)
- ctxt.DotTOC2 = make([]loader.Sym, ctxt.Syms.MaxVersion()+1)
+ ctxt.mkArchSym(which, "TOC", &ctxt.TOC2, &ctxt.TOC)
+
+ // NB: note the +2 below for DotTOC2 compared to the +1 for
+ // DocTOC. This is because loadlibfull() creates an additional
+ // syms version during conversion of loader.Sym symbols to
+ // *sym.Symbol symbols. Symbols that are assigned this final
+ // version are not going to have TOC references, so it should
+ // be ok for them to inherit an invalid .TOC. symbol.
+ if which == BeforeLoadlibFull {
+ ctxt.DotTOC2 = make([]loader.Sym, ctxt.Syms.MaxVersion()+2)
+ } else {
+ ctxt.DotTOC = make([]*sym.Symbol, ctxt.Syms.MaxVersion()+1)
+ }
for i := 0; i <= ctxt.Syms.MaxVersion(); i++ {
if i >= 2 && i < sym.SymVerStatic { // these versions are not used currently
continue
}
- ctxt.DotTOC2[i] = ctxt.loader.LookupOrCreateSym(".TOC.", i)
- ctxt.DotTOC[i] = ctxt.loader.Syms[ctxt.DotTOC2[i]]
+ if ctxt.DotTOC2[i] != 0 {
+ ctxt.mkArchSymVec(which, ".TOC.", i, ctxt.DotTOC2, ctxt.DotTOC)
+ }
}
}
if ctxt.IsElf() {
- ctxt.Rel = ctxt.Syms.Lookup(".rel", 0)
- ctxt.Rela = ctxt.Syms.Lookup(".rela", 0)
- ctxt.RelPLT = ctxt.Syms.Lookup(".rel.plt", 0)
- ctxt.RelaPLT = ctxt.Syms.Lookup(".rela.plt", 0)
+ ctxt.mkArchSym(which, ".rel", &ctxt.Rel2, &ctxt.Rel)
+ ctxt.mkArchSym(which, ".rela", &ctxt.Rela2, &ctxt.Rela)
+ ctxt.mkArchSym(which, ".rel.plt", &ctxt.RelPLT2, &ctxt.RelPLT)
+ ctxt.mkArchSym(which, ".rela.plt", &ctxt.RelaPLT2, &ctxt.RelaPLT)
}
if ctxt.IsDarwin() {
- ctxt.LinkEditGOT = ctxt.Syms.Lookup(".linkedit.got", 0)
- ctxt.LinkEditPLT = ctxt.Syms.Lookup(".linkedit.plt", 0)
+ ctxt.mkArchSym(which, ".linkedit.got", &ctxt.LinkEditGOT2, &ctxt.LinkEditGOT)
+ ctxt.mkArchSym(which, ".linkedit.plt", &ctxt.LinkEditPLT2, &ctxt.LinkEditPLT)
}
}
@@ -2775,7 +2809,7 @@
addToTextp(ctxt)
// Set special global symbols.
- ctxt.setArchSyms()
+ ctxt.setArchSyms(AfterLoadlibFull)
}
func (ctxt *Link) dumpsyms() {
diff --git a/src/cmd/link/internal/ld/main.go b/src/cmd/link/internal/ld/main.go
index 3a7d3b2..2570026 100644
--- a/src/cmd/link/internal/ld/main.go
+++ b/src/cmd/link/internal/ld/main.go
@@ -284,9 +284,9 @@
bench.Start("loadlibfull")
setupdynexp(ctxt)
+ ctxt.setArchSyms(BeforeLoadlibFull)
ctxt.loadlibfull() // XXX do it here for now
- ctxt.setArchSyms()
bench.Start("addexport")
ctxt.addexport()
bench.Start("Gentext")
