Implement type recording for ToBoolean on x64.

src/ia32/macro-assembler-ia32.h

Index: src/ia32/macro-assembler-ia32.h
===================================================================
--- src/ia32/macro-assembler-ia32.h	(revision 8763)
+++ src/ia32/macro-assembler-ia32.h	(working copy)
@@ -209,6 +209,9 @@
   void SafeSet(Register dst, const Immediate& x);
   void SafePush(const Immediate& x);
 
+  // Compare a register against a known root, e.g. undefined, null, true, ...
+  void CompareRoot(Register with, Heap::RootListIndex index);
+
   // Compare object type for heap object.
   // Incoming register is heap_object and outgoing register is map.
   void CmpObjectType(Register heap_object, InstanceType type, Register map);