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

src/ia32/lithium-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1890 matching lines @@
   // All HForceRepresentation instructions should be eliminated in the
   // representation change phase of Hydrogen.
   UNREACHABLE();
   return NULL;
 }
 
 
 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.
   if (from.IsTagged()) {
     if (to.IsDouble()) {
       info()->MarkAsDeferredCalling();
       LOperand* value = UseRegister(instr->value());
       // Temp register only necessary for minus zero check.
       LOperand* temp = instr->deoptimize_on_minus_zero()
                        ? TempRegister()
                        : NULL;
       LNumberUntagD* res = new(zone()) LNumberUntagD(value, temp);
       if (CpuFeatures::IsSafeForSnapshot(SSE2)) {
         return AssignEnvironment(DefineAsRegister(res));
       } 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()) {
         LOperand* value = UseRegister(instr->value());
         return DefineSameAsFirst(new(zone()) LSmiUntag(value, false));
       } else {
         bool truncating = instr->CanTruncateToInt32();
         if (CpuFeatures::IsSafeForSnapshot(SSE2)) {
           LOperand* value = UseRegister(instr->value());
           LOperand* xmm_temp =
@@ skipping 16 matching lines @@
       info()->MarkAsDeferredCalling();
       LOperand* value = CpuFeatures::IsSupported(SSE2)
           ? UseRegisterAtStart(instr->value())
           : UseAtStart(instr->value());
       LOperand* temp = FLAG_inline_new ? TempRegister() : NULL;
 
       // Make sure that temp and result_temp are different registers.
       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();
       bool needs_temp = truncating && !CpuFeatures::IsSupported(SSE3);
       LOperand* value = needs_temp ?
           UseTempRegister(instr->value()) : UseRegister(instr->value());
       LOperand* temp = needs_temp ? TempRegister() : NULL;
       return AssignEnvironment(
           DefineAsRegister(new(zone()) LDoubleToI(value, temp)));
     }
   } else if (from.IsInteger32()) {
     info()->MarkAsDeferredCalling();
     if (to.IsTagged()) {
       HValue* val = instr->value();
       LOperand* value = UseRegister(val);
       if (val->HasRange() && val->range()->IsInSmiRange()) {
         return DefineSameAsFirst(new(zone()) LSmiTag(value));
       } else if (val->CheckFlag(HInstruction::kUint32)) {
         LNumberTagU* result = new(zone()) LNumberTagU(value);
         return AssignEnvironment(AssignPointerMap(DefineSameAsFirst(result)));
       } else {
         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)) {
         LOperand* temp = FixedTemp(xmm1);
         return DefineAsRegister(
             new(zone()) LUint32ToDouble(UseRegister(instr->value()), temp));
       } else {
         return DefineAsRegister(
             new(zone()) LInteger32ToDouble(Use(instr->value())));
       }
@@ skipping 20 matching lines @@
 
 LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
   LUnallocated* temp = TempRegister();
   LCheckPrototypeMaps* result = new(zone()) LCheckPrototypeMaps(temp);
   return AssignEnvironment(result);
 }
 
 
 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)));
 }
 
 
 LInstruction* LChunkBuilder::DoCheckFunction(HCheckFunction* instr) {
   // If the target is in new space, we'll emit a global cell compare and so
   // want the value in a register.  If the target gets promoted before we
   // emit code, we will still get the register but will do an immediate
   // compare instead of the cell compare.  This is safe.
   LOperand* value = instr->target_in_new_space()
       ? UseRegisterAtStart(instr->value()) : UseAtStart(instr->value());
@@ skipping 714 matching lines @@
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseTempRegister(instr->index());
   return DefineSameAsFirst(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32