VM: Improve and fix double negation on MIPS.

runtime/vm/constants_mips.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_CONSTANTS_MIPS_H_
 #define VM_CONSTANTS_MIPS_H_
 
 #include "platform/assert.h"
 
 namespace dart {
@@ skipping 421 matching lines @@
 };
 
 
 enum Cop1Function {
   COP1_ADD = 0x00,
   COP1_SUB = 0x01,
   COP1_MUL = 0x02,
   COP1_DIV = 0x03,
   COP1_SQRT = 0x04,
   COP1_MOV = 0x06,
+  COP1_NEG = 0x07,
   COP1_CVT_S = 0x20,
   COP1_CVT_D = 0x21,
   COP1_CVT_W = 0x24,
   COP1_C_F = 0x30,
   COP1_C_UN = 0x31,
   COP1_C_EQ = 0x32,
   COP1_C_UEQ = 0x33,
   COP1_C_OLT = 0x34,
   COP1_C_ULT = 0x35,
   COP1_C_OLE = 0x36,
@@ skipping 199 matching lines @@
 #endif  // defined(DEBUG)
 
  private:
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(Instr);
 };
 
 }  // namespace dart
 
 #endif  // VM_CONSTANTS_MIPS_H_