Avoid redundant smi check for Math.abs

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 3813 matching lines @@
   ASSERT(instr->value()->Equals(instr->result()));
   Representation r = instr->hydrogen()->value()->representation();
 
   CpuFeatureScope scope(masm(), SSE2);
   if (r.IsDouble()) {
     XMMRegister  scratch = xmm0;
     XMMRegister input_reg = ToDoubleRegister(instr->value());
     __ xorps(scratch, scratch);
     __ subsd(scratch, input_reg);
     __ pand(input_reg, scratch);
-  } else if (r.IsInteger32()) {
+  } else if (r.IsInteger32() || r.IsSmi()) {

[Jakob Kummerow, 2013/07/31 12:27:27]

You can use r.IsSmiOrInteger32() here.

     EmitIntegerMathAbs(instr);
   } else {  // Tagged case.
     DeferredMathAbsTaggedHeapNumber* deferred =
         new(zone()) DeferredMathAbsTaggedHeapNumber(this, instr);
     Register input_reg = ToRegister(instr->value());
     // Smi check.
     __ JumpIfNotSmi(input_reg, deferred->entry());
     EmitIntegerMathAbs(instr);
     __ bind(deferred->exit());
   }
@@ skipping 2678 matching lines @@
                               FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32