X64: Change strategy for spilling to match ia32. It's just better.

src/ia32/assembler-ia32.h

Index: src/ia32/assembler-ia32.h
diff --git a/src/ia32/assembler-ia32.h b/src/ia32/assembler-ia32.h
index be29143ff2e862636c4679a15be93df322a544a4..c76c55cf539170ab5492b09e6a1c6a21870338a7 100644
--- a/src/ia32/assembler-ia32.h
+++ b/src/ia32/assembler-ia32.h
@@ -507,6 +507,8 @@ class Assembler : public Malloced {
   // possible to align the pc offset to a multiple
   // of m. m must be a power of 2.
   void Align(int m);
+  // Aligns code to something that's optimal for a jump target for the platform.
+  void CodeTargetAlign();
 
   // Stack
   void pushad();