Support symbol comparison in crankshaft.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 91634961403391fc80745b8ca284f710f8629f5a..5b4402d41b32e1db1ef167a3995e218431daecab 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -1543,6 +1543,31 @@ void LCodeGen::DoCmpJSObjectEqAndBranch(LCmpJSObjectEqAndBranch* instr) {
 }
 
 
+void LCodeGen::DoCmpSymbolEq(LCmpSymbolEq* instr) {
+  Register left = ToRegister(instr->InputAt(0));
+  Register right = ToRegister(instr->InputAt(1));
+  Register result = ToRegister(instr->result());
+
+  Label done;
+  __ cmp(left, Operand(right));
+  __ mov(result, factory()->false_value());
+  __ j(not_equal, &done, Label::kNear);
+  __ mov(result, factory()->true_value());
+  __ bind(&done);
+}
+
+
+void LCodeGen::DoCmpSymbolEqAndBranch(LCmpSymbolEqAndBranch* instr) {
+  Register left = ToRegister(instr->InputAt(0));
+  Register right = ToRegister(instr->InputAt(1));
+  int false_block = chunk_->LookupDestination(instr->false_block_id());
+  int true_block = chunk_->LookupDestination(instr->true_block_id());
+
+  __ cmp(left, Operand(right));
+  EmitBranch(true_block, false_block, equal);
+}
+
+
 void LCodeGen::DoIsNull(LIsNull* instr) {
   Register reg = ToRegister(instr->InputAt(0));
   Register result = ToRegister(instr->result());