X64 Win64: Reimplement fmod so that it works.

src/arm/codegen-arm.h

 // Copyright 2006-2008 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 358 matching lines @@
 
   // Fast support for Math.random().
   void GenerateRandomPositiveSmi(ZoneList<Expression*>* args);
 
   // Fast support for Math.sin and Math.cos.
   enum MathOp { SIN, COS };
   void GenerateFastMathOp(MathOp op, ZoneList<Expression*>* args);
   inline void GenerateMathSin(ZoneList<Expression*>* args);
   inline void GenerateMathCos(ZoneList<Expression*>* args);
 
+  // Potentially alternative support for modulo operation on numbers.

[William Hesse, 2009/10/20 14:50:51]

I don't understand this comment.  What is it, when is it used, what does it do?

[Lasse Reichstein, 2009/10/22 11:22:53]

It generates code to compute x % y. It's "potential" because it should only be
used on 64-bit Windows.

+  void GenerateNumberMod(ZoneList<Expression*>* args);
+
   // Simple condition analysis.
   enum ConditionAnalysis {
     ALWAYS_TRUE,
     ALWAYS_FALSE,
     DONT_KNOW
   };
   ConditionAnalysis AnalyzeCondition(Expression* cond);
 
   // Methods used to indicate which source code is generated for. Source
   // positions are collected by the assembler and emitted with the relocation
@@ skipping 127 matching lines @@
              constant_rhs_);
     }
   }
 #endif
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_CODEGEN_ARM_H_