Implement HChange support for Smis and use it in Load/StoreNameField

src/ia32/lithium-ia32.cc

Index: src/ia32/lithium-ia32.cc
diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index dec5697f8769b861b8d72e2b44ec9647695e8cc5..90939695b78fec2268761f313916703430eb84c8 100644
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -1908,6 +1908,13 @@ LInstruction* LChunkBuilder::DoForceRepresentation(HForceRepresentation* bad) {
 LInstruction* LChunkBuilder::DoChange(HChange* instr) {
   Representation from = instr->from();
   Representation to = instr->to();
+  if (from.IsSmi()) {
+    if (to.IsTagged()) {
+      LOperand* value = UseRegister(instr->value());
+      return DefineSameAsFirst(new(zone()) LDummyUse(value));
+    }
+    from = Representation::Tagged();
+  }
   // Only mark conversions that might need to allocate as calling rather than
   // all changes. This makes simple, non-allocating conversion not have to force
   // building a stack frame.
@@ -1925,6 +1932,11 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
       } else {
         return AssignEnvironment(DefineX87TOS(res));
       }
+    } else if (to.IsSmi()) {
+      HValue* val = instr->value();
+      LOperand* value = UseRegisterAtStart(val);
+      return AssignEnvironment(
+          DefineSameAsFirst(new(zone()) LCheckSmi(value)));
     } else {
       ASSERT(to.IsInteger32());
       if (instr->value()->type().IsSmi()) {
@@ -1961,6 +1973,10 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
       LUnallocated* result_temp = TempRegister();
       LNumberTagD* result = new(zone()) LNumberTagD(value, temp);
       return AssignPointerMap(Define(result, result_temp));
+    } else if (to.IsSmi()) {
+      LOperand* value = UseRegister(instr->value());
+      return AssignEnvironment(
+          DefineAsRegister(new(zone()) LDoubleToSmi(value)));
     } else {
       ASSERT(to.IsInteger32());
       bool truncating = instr->CanTruncateToInt32();
@@ -1985,6 +2001,15 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
         LNumberTagI* result = new(zone()) LNumberTagI(value);
         return AssignEnvironment(AssignPointerMap(DefineSameAsFirst(result)));
       }
+    } else if (to.IsSmi()) {
+      HValue* val = instr->value();
+      LOperand* value = UseRegister(val);
+      LInstruction* result =
+          DefineSameAsFirst(new(zone()) LInteger32ToSmi(value));
+      if (val->HasRange() && val->range()->IsInSmiRange()) {
+        return result;
+      }
+      return AssignEnvironment(result);
     } else {
       ASSERT(to.IsDouble());
       if (instr->value()->CheckFlag(HInstruction::kUint32)) {
@@ -2025,13 +2050,13 @@ LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
 
 LInstruction* LChunkBuilder::DoCheckSmi(HCheckSmi* instr) {
   LOperand* value = UseAtStart(instr->value());
-  return AssignEnvironment(new(zone()) LCheckSmi(value));
+  return AssignEnvironment(DefineSameAsFirst(new(zone()) LCheckSmi(value)));
 }
 
 
 LInstruction* LChunkBuilder::DoCheckSmiOrInt32(HCheckSmiOrInt32* instr) {
   LOperand* value = UseAtStart(instr->value());
-  return AssignEnvironment(new(zone()) LCheckSmi(value));
+  return AssignEnvironment(DefineSameAsFirst(new(zone()) LCheckSmi(value)));
 }