[lld] r314088 - Move Config->SymbolRenaming to SymbolTable.
Rui Ueyama via llvm-commits
llvm-commits at lists.llvm.org
Sun Sep 24 17:57:18 PDT 2017
Author: ruiu
Date: Sun Sep 24 17:57:18 2017
New Revision: 314088
URL: http://llvm.org/viewvc/llvm-project?rev=314088&view=rev
Log:
Move Config->SymbolRenaming to SymbolTable.
In order to keep track of symbol renaming, we used to have
Config->SymbolRenaming, and whether a symbol is in the map or not
affects its symbol attribute (i.e. "LinkeRedefined" bit).
This patch adds "CanInline" bit to Symbol to aggreagate symbol
information in one place and removed the member from Config since
no one except SymbolTable now uses the table.
Modified:
lld/trunk/ELF/LTO.cpp
lld/trunk/ELF/SymbolTable.cpp
lld/trunk/ELF/SymbolTable.h
lld/trunk/ELF/Symbols.h
Modified: lld/trunk/ELF/LTO.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/LTO.cpp?rev=314088&r1=314087&r2=314088&view=diff
==============================================================================
--- lld/trunk/ELF/LTO.cpp (original)
+++ lld/trunk/ELF/LTO.cpp Sun Sep 24 17:57:18 2017
@@ -153,7 +153,7 @@ void BitcodeCompiler::add(BitcodeFile &F
UsedStartStop.count(ObjSym.getSectionName());
if (R.Prevailing)
undefine(Sym);
- R.LinkerRedefined = Config->RenamedSymbols.count(Sym);
+ R.LinkerRedefined = !Sym->CanInline;
}
checkError(LTOObj->add(std::move(F.Obj), Resols));
}
Modified: lld/trunk/ELF/SymbolTable.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SymbolTable.cpp?rev=314088&r1=314087&r2=314088&view=diff
==============================================================================
--- lld/trunk/ELF/SymbolTable.cpp (original)
+++ lld/trunk/ELF/SymbolTable.cpp Sun Sep 24 17:57:18 2017
@@ -162,11 +162,10 @@ template <class ELFT> void SymbolTable::
Symbol *Real = addUndefined<ELFT>(Saver.save("__real_" + Name));
Symbol *Wrap = addUndefined<ELFT>(Saver.save("__wrap_" + Name));
- // Tell LTO not to eliminate this symbol
+ // Tell LTO not to eliminate this symbol.
Wrap->IsUsedInRegularObj = true;
-
- Config->RenamedSymbols[Real] = {Sym, Real->Binding};
- Config->RenamedSymbols[Sym] = {Wrap, Sym->Binding};
+ defsym(Real, Sym);
+ defsym(Sym, Wrap);
}
// Creates alias for symbol. Used to implement --defsym=ALIAS=SYM.
@@ -177,12 +176,10 @@ void SymbolTable::addSymbolAlias(StringR
error("-defsym: undefined symbol: " + Name);
return;
}
- Symbol *Sym = B->symbol();
- Symbol *AliasSym = addUndefined<ELFT>(Alias);
- // Tell LTO not to eliminate this symbol
- Sym->IsUsedInRegularObj = true;
- Config->RenamedSymbols[AliasSym] = {Sym, AliasSym->Binding};
+ // Tell LTO not to eliminate this symbol.
+ B->symbol()->IsUsedInRegularObj = true;
+ defsym(addUndefined<ELFT>(Alias), B->symbol());
}
// Apply symbol renames created by -wrap and -defsym. The renames are created
@@ -190,12 +187,10 @@ void SymbolTable::addSymbolAlias(StringR
// LTO (if LTO is running) not to include these symbols in IPO. Now that the
// symbols are finalized, we can perform the replacement.
void SymbolTable::applySymbolRenames() {
- for (auto &KV : Config->RenamedSymbols) {
- Symbol *Dst = KV.first;
- Symbol *Src = KV.second.Target;
- Dst->body()->copy(Src->body());
- Dst->File = Src->File;
- Dst->Binding = KV.second.OriginalBinding;
+ for (SymbolRenaming &S : Defsyms) {
+ S.Dst->body()->copy(S.Src->body());
+ S.Dst->File = S.Src->File;
+ S.Dst->Binding = S.Binding;
}
}
@@ -233,6 +228,7 @@ std::pair<Symbol *, bool> SymbolTable::i
Sym->Visibility = STV_DEFAULT;
Sym->IsUsedInRegularObj = false;
Sym->ExportDynamic = false;
+ Sym->CanInline = true;
Sym->Traced = V.Traced;
Sym->VersionId = Config->DefaultSymbolVersion;
SymVector.push_back(Sym);
@@ -525,6 +521,13 @@ SymbolBody *SymbolTable::find(StringRef
return SymVector[V.Idx]->body();
}
+void SymbolTable::defsym(Symbol *Dst, Symbol *Src) {
+ // We want to tell LTO not to inline Dst symbol because LTO doesn't
+ // know the final symbol contents after renaming.
+ Dst->CanInline = false;
+ Defsyms.push_back({Dst, Src, Dst->Binding});
+}
+
template <class ELFT>
Symbol *SymbolTable::addLazyArchive(ArchiveFile *F,
const object::Archive::Symbol Sym) {
Modified: lld/trunk/ELF/SymbolTable.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SymbolTable.h?rev=314088&r1=314087&r2=314088&view=diff
==============================================================================
--- lld/trunk/ELF/SymbolTable.h (original)
+++ lld/trunk/ELF/SymbolTable.h Sun Sep 24 17:57:18 2017
@@ -95,6 +95,7 @@ public:
private:
std::vector<SymbolBody *> findByVersion(SymbolVersion Ver);
std::vector<SymbolBody *> findAllByVersion(SymbolVersion Ver);
+ void defsym(Symbol *Dst, Symbol *Src);
llvm::StringMap<std::vector<SymbolBody *>> &getDemangledSyms();
void handleAnonymousVersion();
@@ -132,6 +133,15 @@ private:
// directive in version scripts.
llvm::Optional<llvm::StringMap<std::vector<SymbolBody *>>> DemangledSyms;
+ struct SymbolRenaming {
+ Symbol *Dst;
+ Symbol *Src;
+ uint8_t Binding;
+ };
+
+ // For -defsym or -wrap.
+ std::vector<SymbolRenaming> Defsyms;
+
// For LTO.
std::unique_ptr<BitcodeCompiler> LTO;
};
Modified: lld/trunk/ELF/Symbols.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Symbols.h?rev=314088&r1=314087&r2=314088&view=diff
==============================================================================
--- lld/trunk/ELF/Symbols.h (original)
+++ lld/trunk/ELF/Symbols.h Sun Sep 24 17:57:18 2017
@@ -365,6 +365,11 @@ struct Symbol {
// --export-dynamic, and by dynamic lists.
unsigned ExportDynamic : 1;
+ // False if LTO shouldn't inline whatever this symbol points to. If a symbol
+ // is overwritten after LTO, LTO shouldn't inline the symbol because it
+ // doesn't know the final contents of the symbol.
+ unsigned CanInline : 1;
+
// True if this symbol is specified by --trace-symbol option.
unsigned Traced : 1;
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