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

src/arm/lithium-arm.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 1869 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();
+  }
   if (from.IsTagged()) {
     if (to.IsDouble()) {
       info()->MarkAsDeferredCalling();
       LOperand* value = UseRegister(instr->value());
       LNumberUntagD* res = new(zone()) LNumberUntagD(value);
       return AssignEnvironment(DefineAsRegister(res));
+    } else if (to.IsSmi()) {
+      HValue* val = instr->value();
+      LOperand* value = UseRegisterAtStart(val);
+      return AssignEnvironment(
+          DefineSameAsFirst(new(zone()) LCheckSmi(value)));
     } else {
       ASSERT(to.IsInteger32());
       LOperand* value = NULL;
       LInstruction* res = NULL;
       if (instr->value()->type().IsSmi()) {
         value = UseRegisterAtStart(instr->value());
         res = DefineAsRegister(new(zone()) LSmiUntag(value, false));
       } else {
         value = UseRegister(instr->value());
         LOperand* temp1 = TempRegister();
@@ skipping 14 matching lines @@
       LOperand* value = UseRegister(instr->value());
       LOperand* temp1 = TempRegister();
       LOperand* temp2 = TempRegister();
 
       // Make sure that the temp and result_temp registers are
       // different.
       LUnallocated* result_temp = TempRegister();
       LNumberTagD* result = new(zone()) LNumberTagD(value, temp1, temp2);
       Define(result, result_temp);
       return AssignPointerMap(result);
+    } else if (to.IsSmi()) {
+      LOperand* value = UseRegister(instr->value());
+      return AssignEnvironment(DefineAsRegister(new(zone()) LDoubleToSmi(value,
+          TempRegister(), TempRegister())));
     } else {
       ASSERT(to.IsInteger32());
       LOperand* value = UseRegister(instr->value());
       LOperand* temp1 = TempRegister();
       LOperand* temp2 = instr->CanTruncateToInt32() ? TempRegister() : NULL;
       LDoubleToI* res = new(zone()) LDoubleToI(value, temp1, temp2);
       return AssignEnvironment(DefineAsRegister(res));
     }
   } else if (from.IsInteger32()) {
     info()->MarkAsDeferredCalling();
     if (to.IsTagged()) {
       HValue* val = instr->value();
       LOperand* value = UseRegisterAtStart(val);
       if (val->CheckFlag(HInstruction::kUint32)) {
         LNumberTagU* result = new(zone()) LNumberTagU(value);
         return AssignEnvironment(AssignPointerMap(DefineSameAsFirst(result)));
       } else if (val->HasRange() && val->range()->IsInSmiRange()) {
         return DefineAsRegister(new(zone()) LSmiTag(value));
       } else {
         LNumberTagI* result = new(zone()) LNumberTagI(value);
         return AssignEnvironment(AssignPointerMap(DefineAsRegister(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)) {
         return DefineAsRegister(
             new(zone()) LUint32ToDouble(UseRegister(instr->value())));
       } else {
         return DefineAsRegister(
             new(zone()) LInteger32ToDouble(Use(instr->value())));
       }
     }
@@ skipping 73 matching lines @@
                              parameter_count);
 }
 
 
 LInstruction* LChunkBuilder::DoConstant(HConstant* instr) {
   Representation r = instr->representation();
   if (r.IsInteger32()) {
     return DefineAsRegister(new(zone()) LConstantI);
   } else if (r.IsDouble()) {
     return DefineAsRegister(new(zone()) LConstantD);
-  } else if (r.IsTagged()) {
+  } else if (r.IsTagged() || r.IsSmi()) {
     return DefineAsRegister(new(zone()) LConstantT);
   } else {
     UNREACHABLE();
     return NULL;
   }
 }
 
 
 LInstruction* LChunkBuilder::DoLoadGlobalCell(HLoadGlobalCell* instr) {
   LLoadGlobalCell* result = new(zone()) LLoadGlobalCell;
@@ skipping 552 matching lines @@
 
 
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseRegister(instr->index());
   return DefineAsRegister(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal