Set the FPU precision control to double-precision.

src/x87/macro-assembler-x87.h

 // 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.
 
 #ifndef V8_X87_MACRO_ASSEMBLER_X87_H_
 #define V8_X87_MACRO_ASSEMBLER_X87_H_
 
 #include "src/assembler.h"
 #include "src/bailout-reason.h"
 #include "src/frames.h"
@@ skipping 407 matching lines @@
   // The contents of the scratch register will be overwritten.
   void IsInstanceJSObjectType(Register map, Register scratch, Label* fail);
 
   // FCmp is similar to integer cmp, but requires unsigned
   // jcc instructions (je, ja, jae, jb, jbe, je, and jz).
   void FCmp();
   void FXamMinusZero();
   void FXamSign();
   void X87CheckIA();
   void X87SetRC(int rc);
+  void X87SetFPUCW(int cw);
 
   void ClampUint8(Register reg);
   void ClampTOSToUint8(Register result_reg);
 
   void SlowTruncateToI(Register result_reg, Register input_reg,
       int offset = HeapNumber::kValueOffset - kHeapObjectTag);
 
   void TruncateHeapNumberToI(Register result_reg, Register input_reg);
   void TruncateX87TOSToI(Register result_reg);
 
@@ skipping 637 matching lines @@
   }                                                                       \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_X87_MACRO_ASSEMBLER_X87_H_