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-rw-r--r--lib/MC/MCELFStreamer.cpp54
1 files changed, 1 insertions, 53 deletions
diff --git a/lib/MC/MCELFStreamer.cpp b/lib/MC/MCELFStreamer.cpp
index a2d94f5ba1..157c0c0b64 100644
--- a/lib/MC/MCELFStreamer.cpp
+++ b/lib/MC/MCELFStreamer.cpp
@@ -240,49 +240,6 @@ void MCELFStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
Symbol->setVariableValue(AddValueSymbols(Value));
}
-// This is a hack. To be able to implement weakrefs the writer has to be able
-// to distinguish
-// .weakref foo, bar
-// .long foo
-// from
-// .weakref foo, bar
-// .long bar
-// since the first case should produce a weak undefined reference and the second
-// one a strong one.
-// If we created foo as a regular alias pointing to bar (foo = bar), then
-// MCExpr::EvaluateAsRelocatable would recurse on foo and the writer would
-// never see it used in a relocation.
-// What we do is create a MCTargetExpr that when evaluated produces a symbol
-// ref to a temporary symbol. This temporary symbol in turn is a variable
-// that equals the original symbol (tmp = bar). With this hack the writer
-// gets a relocation with tmp and can correctly implement weak references.
-
-namespace {
-class WeakRefExpr : public MCTargetExpr {
-private:
- const MCSymbolRefExpr *Alias;
-
- explicit WeakRefExpr(const MCSymbolRefExpr *Alias_)
- : MCTargetExpr(), Alias(Alias_) {}
-
-public:
- virtual void PrintImpl(raw_ostream &OS) const {
- llvm_unreachable("Unimplemented");
- }
-
- virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
- const MCAsmLayout *Layout) const {
- Res = MCValue::get(Alias, 0, 0);
- return true;
- }
-
- static const WeakRefExpr *Create(const MCSymbol *Alias, MCContext &Ctx) {
- const MCSymbolRefExpr *A = MCSymbolRefExpr::Create(Alias, Ctx);
- return new (Ctx) WeakRefExpr(A);
- }
-};
-} // end anonymous namespace
-
void MCELFStreamer::SwitchSection(const MCSection *Section) {
const MCSymbol *Grp = static_cast<const MCSectionELF *>(Section)->getGroup();
if (Grp)
@@ -294,16 +251,7 @@ void MCELFStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
getAssembler().getOrCreateSymbolData(*Symbol);
MCSymbolData &AliasSD = getAssembler().getOrCreateSymbolData(*Alias);
AliasSD.setFlags(AliasSD.getFlags() | ELF_Other_Weakref);
-
- // Create the alias that actually points to Symbol
- const MCSymbolRefExpr *SymRef = MCSymbolRefExpr::Create(Symbol, getContext());
- MCSymbol *RealAlias = getContext().CreateTempSymbol();
- RealAlias->setVariableValue(SymRef);
-
- MCSymbolData &RealAliasSD = getAssembler().getOrCreateSymbolData(*RealAlias);
- RealAliasSD.setFlags(RealAliasSD.getFlags() | ELF_Other_Weakref);
-
- const MCExpr *Value = WeakRefExpr::Create(RealAlias, getContext());
+ const MCExpr *Value = MCSymbolRefExpr::Create(Symbol, getContext());
Alias->setVariableValue(Value);
}