MIPS[64]: Fix `MIPS: Improve Float(32|64)(Max|Min)`.

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

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/crankshaft/mips64/lithium-codegen-mips64.h"
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/crankshaft/hydrogen-osr.h"
 #include "src/crankshaft/mips64/lithium-gap-resolver-mips64.h"
@@ skipping 1869 matching lines @@
      DCHECK(condition == le);
      __  Movn(result_reg, left_reg, scratch);
      __  Movz(result_reg, right_reg, scratch);
     }
   } else {
     DCHECK(instr->hydrogen()->representation().IsDouble());
     FPURegister left_reg = ToDoubleRegister(left);
     FPURegister right_reg = ToDoubleRegister(right);
     FPURegister result_reg = ToDoubleRegister(instr->result());
     Label nan, done;
-    if (operation == HMathMinMax::kMathMax) {
+    if (left_reg.is(right_reg)) {

[ivica.bogosavljevic, 2016/12/07 14:59:15]

can we move this check to Float64Max?

[Ilija.Pavlovic1, 2016/12/08 13:50:06]

Yes. Now, these checks are in Float(32|64)(Max|Min) functions.

Done.

+      __ Move(result_reg, left_reg);
+    } else if (operation == HMathMinMax::kMathMax) {
       __ Float64Max(result_reg, left_reg, right_reg, &nan);
     } else {
       DCHECK(operation == HMathMinMax::kMathMin);
       __ Float64Min(result_reg, left_reg, right_reg, &nan);
     }
     __ Branch(&done);
 
     __ bind(&nan);
     __ add_d(result_reg, left_reg, right_reg);
 
@@ skipping 3719 matching lines @@
   __ ld(result, FieldMemOperand(scratch,
                                 FixedArray::kHeaderSize - kPointerSize));
   __ bind(deferred->exit());
   __ bind(&done);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8