Add PushAddress(ExternalReference) for X64.

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index f7db250f9ec64b11dab52563cb93baf28c432e2c..db1b6af29ba2d1d5e5c5c9db742ea7f2edc10e3a 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -150,6 +150,20 @@ int MacroAssembler::LoadAddressSize(ExternalReference source) {
 }
 
 
+void MacroAssembler::PushAddress(ExternalReference source) {
+  int64_t address = reinterpret_cast<int64_t>(source.address());
+  if (is_int32(address) && !Serializer::enabled()) {
+    if (emit_debug_code()) {
+      movq(kScratchRegister, BitCast<int64_t>(kZapValue), RelocInfo::NONE);
+    }
+    push(Immediate(static_cast<int32_t>(address)));
+    return;
+  }
+  LoadAddress(kScratchRegister, source);
+  push(kScratchRegister);
+}
+
+
 void MacroAssembler::LoadRoot(Register destination, Heap::RootListIndex index) {
   ASSERT(root_array_available_);
   movq(destination, Operand(kRootRegister,