Implement IC for storing to dictionary case objects....

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
===================================================================
--- src/x64/macro-assembler-x64.cc	(revision 4975)
+++ src/x64/macro-assembler-x64.cc	(working copy)
@@ -105,12 +105,6 @@
 }
 
 
-// For page containing |object| mark region covering [object+offset] dirty.
-// object is the object being stored into, value is the object being stored.
-// If offset is zero, then the index register contains the array index into
-// the elements array represented a zero extended int32. Otherwise it can be
-// used as a scratch register.
-// All registers are clobbered by the operation.
 void MacroAssembler::RecordWrite(Register object,
                                  int offset,
                                  Register value,
@@ -141,6 +135,35 @@
 }
 
 
+void MacroAssembler::RecordWrite(Register object,
+                                 Register address,
+                                 Register value) {
+  // The compiled code assumes that record write doesn't change the
+  // context register, so we check that none of the clobbered
+  // registers are esi.
+  ASSERT(!object.is(rsi) && !value.is(rsi) && !address.is(rsi));
+
+  // First, check if a write barrier is even needed. The tests below
+  // catch stores of Smis and stores into young gen.
+  Label done;
+  JumpIfSmi(value, &done);
+
+  InNewSpace(object, value, equal, &done);
+
+  RecordWriteHelper(object, address, value);
+
+  bind(&done);
+
+  // Clobber all input registers when running with the debug-code flag
+  // turned on to provoke errors.
+  if (FLAG_debug_code) {
+    movq(object, BitCast<int64_t>(kZapValue), RelocInfo::NONE);
+    movq(address, BitCast<int64_t>(kZapValue), RelocInfo::NONE);
+    movq(value, BitCast<int64_t>(kZapValue), RelocInfo::NONE);
+  }
+}
+
+
 void MacroAssembler::RecordWriteNonSmi(Register object,
                                        int offset,
                                        Register scratch,