S390 [Crankshaft]: Use LoadPositive for MathAbs

src/crankshaft/s390/lithium-codegen-s390.cc

Index: src/crankshaft/s390/lithium-codegen-s390.cc
diff --git a/src/crankshaft/s390/lithium-codegen-s390.cc b/src/crankshaft/s390/lithium-codegen-s390.cc
index 283d219ddb73d19edd17f55f1bf8bb5b5646e67f..e21cc190e59c3bc4f6afe0abca9e8da72abcf044 100644
--- a/src/crankshaft/s390/lithium-codegen-s390.cc
+++ b/src/crankshaft/s390/lithium-codegen-s390.cc
@@ -3387,31 +3387,17 @@ void LCodeGen::DoDeferredMathAbsTaggedHeapNumber(LMathAbs* instr) {
 void LCodeGen::EmitMathAbs(LMathAbs* instr) {
   Register input = ToRegister(instr->value());
   Register result = ToRegister(instr->result());
-  Label done;
-  __ CmpP(input, Operand::Zero());
-  __ Move(result, input);
-  __ bge(&done, Label::kNear);
-  __ LoadComplementRR(result, result);
+  __ LoadPositiveP(result, input);
   // Deoptimize on overflow.
   DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow, cr0);
-  __ bind(&done);
 }
 
 #if V8_TARGET_ARCH_S390X
 void LCodeGen::EmitInteger32MathAbs(LMathAbs* instr) {
   Register input = ToRegister(instr->value());
   Register result = ToRegister(instr->result());
-  Label done;
-  __ Cmp32(input, Operand::Zero());
-  __ Move(result, input);
-  __ bge(&done, Label::kNear);
-
-  // Deoptimize on overflow.
-  __ Cmp32(input, Operand(0x80000000));
-  DeoptimizeIf(eq, instr, DeoptimizeReason::kOverflow);
-
-  __ LoadComplementRR(result, result);
-  __ bind(&done);
+  __ LoadPositive32(result, input);

[john.yan, 2016/12/21 21:03:52]

maybe more lgfr to here instead of putting in MacroAssembler?

+  DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
 }
 #endif