Rollback of r17108, r17106, r17104 in trunk branch.

src/ia32/lithium-codegen-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 2258 matching lines @@
         __ fmul_i(1);
         break;
       case Token::DIV:
         __ fdiv_i(1);
         break;
       case Token::MOD: {
         // Pass two doubles as arguments on the stack.
         __ PrepareCallCFunction(4, eax);
         X87Mov(Operand(esp, 1 * kDoubleSize), right);
         X87Mov(Operand(esp, 0), left);
-        X87Free(right);
-        ASSERT(left.is(result));
         X87PrepareToWrite(result);
         __ CallCFunction(
             ExternalReference::double_fp_operation(Token::MOD, isolate()),
             4);
 
         // Return value is in st(0) on ia32.
         X87CommitWrite(result);
         break;
       }
       default:
@@ skipping 2720 matching lines @@
   Register input = ToRegister(instr->value());
   __ SmiTag(input);
   if (!instr->hydrogen()->value()->HasRange() ||
       !instr->hydrogen()->value()->range()->IsInSmiRange()) {
     DeoptimizeIf(overflow, instr->environment());
   }
 }
 
 
 void LCodeGen::DoUint32ToDouble(LUint32ToDouble* instr) {
+  CpuFeatureScope scope(masm(), SSE2);
   LOperand* input = instr->value();
   LOperand* output = instr->result();
-  if (CpuFeatures::IsSupported(SSE2)) {
-    CpuFeatureScope scope(masm(), SSE2);
-    LOperand* temp = instr->temp();
+  LOperand* temp = instr->temp();
 
-    __ LoadUint32(ToDoubleRegister(output),
-                  ToRegister(input),
-                  ToDoubleRegister(temp));
-  } else {
-    X87Register res = ToX87Register(output);
-    X87PrepareToWrite(res);
-    __ LoadUint32NoSSE2(ToRegister(input));
-    X87CommitWrite(res);
-  }
+  __ LoadUint32(ToDoubleRegister(output),
+                ToRegister(input),
+                ToDoubleRegister(temp));
 }
 
 
 void LCodeGen::DoNumberTagI(LNumberTagI* instr) {
   class DeferredNumberTagI V8_FINAL : public LDeferredCode {
    public:
     DeferredNumberTagI(LCodeGen* codegen,
                        LNumberTagI* instr,
                        const X87Stack& x87_stack)
         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
@@ skipping 1345 matching lines @@
                               FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32