Generate code for store buffer updates in open-coded object field stores.

runtime/vm/assembler_ia32.h

Index: runtime/vm/assembler_ia32.h
diff --git a/runtime/vm/assembler_ia32.h b/runtime/vm/assembler_ia32.h
index 56c244330f9926835279d2d5ecdbad69383668de..c0984fe7e434aa9f0d8d60d1b4712403ff27e891 100644
--- a/runtime/vm/assembler_ia32.h
+++ b/runtime/vm/assembler_ia32.h
@@ -302,6 +302,9 @@ class Assembler : public ValueObject {
   void popl(Register reg);
   void popl(const Address& address);
 
+  void pushal();
+  void popal();
+
   void movl(Register dst, const Immediate& src);
   void movl(Register dst, Register src);
 
@@ -521,6 +524,13 @@ class Assembler : public ValueObject {
                        const FieldAddress& dest,  // Where we are storing into.
                        Register value);  // Value we are storing.
 
+  void StoreIntoObjectNoBarrier(Register object,
+                                const FieldAddress& dest,
+                                Register value);
+  void StoreIntoObjectNoBarrier(Register object,
+                                const FieldAddress& dest,
+                                const Object& value);
+
   void DoubleNegate(XmmRegister d);
   void FloatNegate(XmmRegister f);