Add integer negate back to list of intrinsified methods.

runtime/vm/intrinsifier_x64.cc

 // Copyright (c) 2012, 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.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 669 matching lines @@
   // cannot tag the result.
   __ cmpq(RAX, Immediate(0x4000000000000000));
   __ j(EQUAL, &fall_through);
   __ SmiTag(RAX);
   __ ret();
   __ Bind(&fall_through);
   return false;
 }
 
 
+bool Intrinsifier::Integer_negate(Assembler* assembler) {
+  Label fall_through;
+  __ movq(RAX, Address(RSP, + 1 * kWordSize));
+  __ testq(RAX, Immediate(kSmiTagMask));
+  __ j(NOT_ZERO, &fall_through, Assembler::kNearJump);  // Non-smi value.
+  __ negq(RAX);
+  __ j(OVERFLOW, &fall_through, Assembler::kNearJump);
+  // Result is in RAX.
+  __ ret();
+  __ Bind(&fall_through);
+  return false;
+}
+
+
 bool Intrinsifier::Integer_bitAndFromInteger(Assembler* assembler) {
   Label fall_through;
   TestBothArgumentsSmis(assembler, &fall_through);
   // RAX is the right argument.
   __ andq(RAX, Address(RSP, + 2 * kWordSize));
   // Result is in RAX.
   __ ret();
   __ Bind(&fall_through);
   return false;
 }
@@ skipping 703 matching lines @@
   __ LoadObject(RAX, bool_true);
   __ ret();
   return true;
 }
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64