Merge up to 8597 to experimental/gc from the bleeding edge.

src/x64/assembler-x64.h

Index: src/x64/assembler-x64.h
===================================================================
--- src/x64/assembler-x64.h	(revision 8618)
+++ src/x64/assembler-x64.h	(working copy)
@@ -646,6 +646,7 @@
   void push_imm32(int32_t imm32);
   void push(Register src);
   void push(const Operand& src);
+  void push(Handle<Object> handle);
 
   void pop(Register dst);
   void pop(const Operand& dst);
@@ -1173,7 +1174,7 @@
   // Call near relative 32-bit displacement, relative to next instruction.
   void call(Label* L);
   void call(Handle<Code> target,
-            RelocInfo::Mode rmode,
+            RelocInfo::Mode rmode = RelocInfo::CODE_TARGET,
             unsigned ast_id = kNoASTId);
 
   // Calls directly to the given address using a relative offset.
@@ -1355,7 +1356,9 @@
   void Print();
 
   // Check the code size generated from label to here.
-  int SizeOfCodeGeneratedSince(Label* l) { return pc_offset() - l->pos(); }
+  int SizeOfCodeGeneratedSince(Label* label) {
+    return pc_offset() - label->pos();
+  }
 
   // Mark address of the ExitJSFrame code.
   void RecordJSReturn();