MIPS: Improve Float(32|64)(Max|Min).

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 b5839f3d4aa7b3006b35aefa7cd4929deb642c37..c8383d1efdfec9c8b2ed703beef45dc29b5bf02b 100644
--- a/src/crankshaft/mips64/lithium-codegen-mips64.cc
+++ b/src/crankshaft/mips64/lithium-codegen-mips64.cc
@@ -1888,16 +1888,15 @@ void LCodeGen::DoMathMinMax(LMathMinMax* instr) {
     FPURegister result_reg = ToDoubleRegister(instr->result());
     Label nan, done;
     if (operation == HMathMinMax::kMathMax) {
-      __ MaxNaNCheck_d(result_reg, left_reg, right_reg, &nan);
+      __ Float64Max(result_reg, left_reg, right_reg, &nan);
     } else {
       DCHECK(operation == HMathMinMax::kMathMin);
-      __ MinNaNCheck_d(result_reg, left_reg, right_reg, &nan);
+      __ Float64Min(result_reg, left_reg, right_reg, &nan);
     }
     __ Branch(&done);
 
     __ bind(&nan);
-    __ LoadRoot(scratch, Heap::kNanValueRootIndex);
-    __ ldc1(result_reg, FieldMemOperand(scratch, HeapNumber::kValueOffset));
+    __ add_d(result_reg, left_reg, right_reg);
 
     __ bind(&done);
   }