MIPS: Implement Neg_d and Neg_s instruction macros.

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

Index: src/crankshaft/mips/lithium-codegen-mips.cc
diff --git a/src/crankshaft/mips/lithium-codegen-mips.cc b/src/crankshaft/mips/lithium-codegen-mips.cc
index 08357d3a76f80dbb5ca1e3d9f989f34f1563a862..bc58e13c190b76a3e0db6868cd1aa63964d02447 100644
--- a/src/crankshaft/mips/lithium-codegen-mips.cc
+++ b/src/crankshaft/mips/lithium-codegen-mips.cc
@@ -3445,10 +3445,8 @@ void LCodeGen::DoMathPowHalf(LMathPowHalf* instr) {
   // Math.sqrt(-Infinity) == NaN
   Label done;
   __ Move(temp, static_cast<double>(-V8_INFINITY));
-  __ BranchF(USE_DELAY_SLOT, &done, NULL, eq, temp, input);
-  // Set up Infinity in the delay slot.
-  // result is overwritten if the branch is not taken.
-  __ neg_d(result, temp);
+  __ Neg_d(result, temp);
+  __ BranchF(&done, NULL, eq, temp, input);
 
   // Add +0 to convert -0 to +0.
   __ add_d(result, input, kDoubleRegZero);