Eliminate map checks of constant values.

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 38d2011d0b736badcf452b9254febc7ef6d1fa38..d1bb4aa97570183f993313c476e2d3b7db705cb5 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -5802,6 +5802,7 @@ void LCodeGen::DoCheckMapCommon(Register reg,
 
 
 void LCodeGen::DoCheckMaps(LCheckMaps* instr) {
+  if (instr->hydrogen()->CanOmitMapChecks()) return;
   LOperand* input = instr->value();
   ASSERT(input->IsRegister());
   Register reg = ToRegister(input);
@@ -5992,6 +5993,7 @@ void LCodeGen::DoClampTToUint8NoSSE2(LClampTToUint8NoSSE2* instr) {
 
 
 void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
+  if (instr->hydrogen()->CanOmitPrototypeChecks()) return;
   Register reg = ToRegister(instr->temp());
 
   ZoneList<Handle<JSObject> >* prototypes = instr->prototypes();
@@ -5999,11 +6001,9 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
 
   ASSERT(prototypes->length() == maps->length());
 
-  if (!instr->hydrogen()->CanOmitPrototypeChecks()) {
-    for (int i = 0; i < prototypes->length(); i++) {
-      __ LoadHeapObject(reg, prototypes->at(i));
-      DoCheckMapCommon(reg, maps->at(i), instr);
-    }
+  for (int i = 0; i < prototypes->length(); i++) {
+    __ LoadHeapObject(reg, prototypes->at(i));
+    DoCheckMapCommon(reg, maps->at(i), instr);
   }
 }