Implement Math.ceil via Math.floor.

src/math.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 56 matching lines @@
 
 // ECMA 262 - 15.8.2.5
 // The naming of y and x matches the spec, as does the order in which
 // ToNumber (valueOf) is called.
 function MathAtan2(y, x) {
   return %Math_atan2(TO_NUMBER_INLINE(y), TO_NUMBER_INLINE(x));
 }
 
 // ECMA 262 - 15.8.2.6
 function MathCeil(x) {
-  return %Math_ceil(TO_NUMBER_INLINE(x));
+  return -MathFloor(-x);
 }
 
 // ECMA 262 - 15.8.2.7
 function MathCos(x) {
   x = MathAbs(x);  // Convert to number and get rid of -0.
   return TrigonometricInterpolation(x, 1);
 }
 
 // ECMA 262 - 15.8.2.8
 function MathExp(x) {
@@ skipping 253 matching lines @@
     "sin", MathSin,
     "sqrt", MathSqrt,
     "tan", MathTan,
     "atan2", MathAtan2,
     "pow", MathPow,
     "max", MathMax,
     "min", MathMin,
     "imul", MathImul
   ));
 
+  %SetInlineBuiltinFlag(MathCeil);
   %SetInlineBuiltinFlag(MathRandom);
   %SetInlineBuiltinFlag(MathSin);
   %SetInlineBuiltinFlag(MathCos);
   %SetInlineBuiltinFlag(MathTan);
   %SetInlineBuiltinFlag(TrigonometricInterpolation);
 }
 
 SetUpMath();