Merge r8237 to V8 3.2 branch. Fix bug v8:1434, optimized compare of undefined can fail.

src/ia32/lithium-codegen-ia32.cc

 // Copyright 2011 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 3406 matching lines @@
   if (instr->needs_check()) {
     __ test(ToRegister(input), Immediate(kSmiTagMask));
     DeoptimizeIf(not_zero, instr->environment());
   }
   __ SmiUntag(ToRegister(input));
 }
 
 
 void LCodeGen::EmitNumberUntagD(Register input_reg,
                                 XMMRegister result_reg,
+                                bool deoptimize_on_undefined,
                                 LEnvironment* env) {
-  NearLabel load_smi, heap_number, done;
+  NearLabel load_smi, done;
 
   // Smi check.
   __ test(input_reg, Immediate(kSmiTagMask));
   __ j(zero, &load_smi, not_taken);
 
   // Heap number map check.
   __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
          factory()->heap_number_map());
-  __ j(equal, &heap_number);
+  if (deoptimize_on_undefined) {
+    DeoptimizeIf(not_equal, env);
+  } else {
+    NearLabel heap_number;
+    __ j(equal, &heap_number);
+    __ cmp(input_reg, factory()->undefined_value());
+    DeoptimizeIf(not_equal, env);
 
-  __ cmp(input_reg, factory()->undefined_value());
-  DeoptimizeIf(not_equal, env);
+    // Convert undefined to NaN.
+    ExternalReference nan = ExternalReference::address_of_nan();
+    __ movdbl(result_reg, Operand::StaticVariable(nan));
+    __ jmp(&done);
 
-  // Convert undefined to NaN.
-  ExternalReference nan = ExternalReference::address_of_nan();
-  __ movdbl(result_reg, Operand::StaticVariable(nan));
-  __ jmp(&done);
-
+    __ bind(&heap_number);
+  }
   // Heap number to XMM conversion.
-  __ bind(&heap_number);
   __ movdbl(result_reg, FieldOperand(input_reg, HeapNumber::kValueOffset));
   __ jmp(&done);
 
   // Smi to XMM conversion
   __ bind(&load_smi);
   __ SmiUntag(input_reg);  // Untag smi before converting to float.
   __ cvtsi2sd(result_reg, Operand(input_reg));
   __ SmiTag(input_reg);  // Retag smi.
   __ bind(&done);
 }
@@ skipping 112 matching lines @@
 
 void LCodeGen::DoNumberUntagD(LNumberUntagD* instr) {
   LOperand* input = instr->InputAt(0);
   ASSERT(input->IsRegister());
   LOperand* result = instr->result();
   ASSERT(result->IsDoubleRegister());
 
   Register input_reg = ToRegister(input);
   XMMRegister result_reg = ToDoubleRegister(result);
 
-  EmitNumberUntagD(input_reg, result_reg, instr->environment());
+  EmitNumberUntagD(input_reg, result_reg,
+                   instr->hydrogen()->deoptimize_on_undefined(),
+                   instr->environment());
 }
 
 
 void LCodeGen::DoDoubleToI(LDoubleToI* instr) {
   LOperand* input = instr->InputAt(0);
   ASSERT(input->IsDoubleRegister());
   LOperand* result = instr->result();
   ASSERT(result->IsRegister());
 
   XMMRegister input_reg = ToDoubleRegister(input);
@@ skipping 573 matching lines @@
   ASSERT(osr_pc_offset_ == -1);
   osr_pc_offset_ = masm()->pc_offset();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32