MIPS: Implement Neg_d and Neg_s instruction macros.

src/crankshaft/mips64/lithium-codegen-mips64.cc

Index: src/crankshaft/mips64/lithium-codegen-mips64.cc
diff --git a/src/crankshaft/mips64/lithium-codegen-mips64.cc b/src/crankshaft/mips64/lithium-codegen-mips64.cc
index 32b320bc79c4fa2402f78b484a0fbda20bbc2ccc..1d939212ad57ee124cb537312c2513e6bb2b01f6 100644
--- a/src/crankshaft/mips64/lithium-codegen-mips64.cc
+++ b/src/crankshaft/mips64/lithium-codegen-mips64.cc
@@ -3652,10 +3652,8 @@ 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);