Implement support for Math.imul in Crankshaft.

src/math.js

Index: src/math.js
diff --git a/src/math.js b/src/math.js
index e5ab70cc1eb6ee236c79e21db7d73d633533a6b0..9ba1934b851a7224c1ea310fd03597e5ec185707 100644
--- a/src/math.js
+++ b/src/math.js
@@ -213,6 +213,13 @@ function MathTan(x) {
   return %_MathTan(x);
 }
 
+// Non-standard extension.
+function MathImul(x, y) {
+  if (!IS_NUMBER(x)) x = NonNumberToNumber(x);
+  if (!IS_NUMBER(y)) y = NonNumberToNumber(y);
+  return %NumberImul(x, y);

[Sven Panne, 2013/04/29 06:36:00]

I think the right way to implement this would be renaming this to "_MathImul",
add kMathImul to INLINE_FUNCTION_LIST instead of RUNTIME_FUNCTION_LIST_ALWAYS,
and implement a HOptimizedGraphBuilder::GenerateMathImul.

As it is, I am relatively sure that we get some bailouts, though I haven't
tested it.

+}
+
 
 // -------------------------------------------------------------------
 
@@ -283,7 +290,8 @@ function SetUpMath() {
     "atan2", MathAtan2,
     "pow", MathPow,
     "max", MathMax,
-    "min", MathMin
+    "min", MathMin,
+    "imul", MathImul
   ));
 }