Crankshaft support for polymorphic array handling

src/x64/lithium-x64.cc

Index: src/x64/lithium-x64.cc
diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index 1e16a55c0968b281c667378384a5067e12250dde..138219b49a6f247a0498284a022c39edaf7106a6 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -1108,6 +1108,9 @@ LInstruction* LChunkBuilder::DoTest(HTest* instr) {
     HCompareSymbolEq* compare = HCompareSymbolEq::cast(v);
     return new LCmpSymbolEqAndBranch(UseRegisterAtStart(compare->left()),
                                      UseRegisterAtStart(compare->right()));
+  } else if (v->IsCompareConstantEq()) {
+    HCompareConstantEq* compare = HCompareConstantEq::cast(v);
+    return new LCmpConstantEqAndBranch(UseRegisterAtStart(compare->value()));
   } else if (v->IsTypeofIs()) {
     HTypeofIs* typeof_is = HTypeofIs::cast(v);
     return new LTypeofIsAndBranch(UseTempRegister(typeof_is->value()));
@@ -1519,6 +1522,13 @@ LInstruction* LChunkBuilder::DoCompareSymbolEq(
 }
 
 
+LInstruction* LChunkBuilder::DoCompareConstantEq(
+    HCompareConstantEq* instr) {
+  LOperand* left = UseRegisterAtStart(instr->value());
+  return DefineAsRegister(new LCmpConstantEq(left));
+}
+
+
 LInstruction* LChunkBuilder::DoIsNull(HIsNull* instr) {
   ASSERT(instr->value()->representation().IsTagged());
   LOperand* value = UseRegisterAtStart(instr->value());
@@ -1601,6 +1611,12 @@ LInstruction* LChunkBuilder::DoExternalArrayLength(
 }
 
 
+LInstruction* LChunkBuilder::DoElementsKind(HElementsKind* instr) {
+  LOperand* object = UseRegisterAtStart(instr->value());
+  return DefineAsRegister(new LElementsKind(object));
+}
+
+
 LInstruction* LChunkBuilder::DoValueOf(HValueOf* instr) {
   LOperand* object = UseRegister(instr->value());
   LValueOf* result = new LValueOf(object);