A64: Remove temporary sxtw instructions

src/a64/macro-assembler-a64.cc

 // Copyright 2013 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 2806 matching lines @@
                      result,
                      0,
                      true,   // is_truncating
                      true);  // skip_fastpath
   CallStub(&stub);  // DoubleToIStub preserves any registers it needs to clobber
 
   Drop(1, kDoubleSize);  // Drop the double input on the stack.
   Pop(lr);
 
   Bind(&done);
-
-  // TODO(rmcilroy): Remove this Sxtw once the following bug is fixed:
-  // https://code.google.com/p/v8/issues/detail?id=3149
-  Sxtw(result, result.W());
 }
 
 
 void MacroAssembler::TruncateHeapNumberToI(Register result,
                                            Register object) {
   Label done;
   ASSERT(!result.is(object));
   ASSERT(jssp.Is(StackPointer()));
 
   Ldr(fp_scratch, FieldMemOperand(object, HeapNumber::kValueOffset));
 
   // Try to convert the double to an int64. If successful, the bottom 32 bits
   // contain our truncated int32 result.
   TryConvertDoubleToInt64(result, fp_scratch, &done);
 
   // If we fell through then inline version didn't succeed - call stub instead.
   Push(lr);
   DoubleToIStub stub(object,
                      result,
                      HeapNumber::kValueOffset - kHeapObjectTag,
                      true,   // is_truncating
                      true);  // skip_fastpath
   CallStub(&stub);  // DoubleToIStub preserves any registers it needs to clobber
   Pop(lr);
 
   Bind(&done);
-
-  // TODO(rmcilroy): Remove this Sxtw once the following bug is fixed:
-  // https://code.google.com/p/v8/issues/detail?id=3149
-  Sxtw(result, result.W());
 }
 
 
 void MacroAssembler::Prologue(PrologueFrameMode frame_mode) {
   if (frame_mode == BUILD_STUB_FRAME) {
     ASSERT(StackPointer().Is(jssp));
     UseScratchRegisterScope temps(this);
     Register temp = temps.AcquireX();
     __ Mov(temp, Operand(Smi::FromInt(StackFrame::STUB)));
     // Compiled stubs don't age, and so they don't need the predictable code
@@ skipping 2258 matching lines @@
   }
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_A64