MIPS: Use weak cells to embed maps in store handler.

src/ic/mips/handler-compiler-mips.cc

Index: src/ic/mips/handler-compiler-mips.cc
diff --git a/src/ic/mips/handler-compiler-mips.cc b/src/ic/mips/handler-compiler-mips.cc
index 2a8d3b86f18adea2de25370046e7c91cd8a40b22..9275db1b49048e18fe9495339830519e8ce4cfdd 100644
--- a/src/ic/mips/handler-compiler-mips.cc
+++ b/src/ic/mips/handler-compiler-mips.cc
@@ -321,10 +321,23 @@ void NamedStoreHandlerCompiler::GenerateRestoreName(Label* label,
 }
 
 
-void NamedStoreHandlerCompiler::GenerateRestoreNameAndMap(
-    Handle<Name> name, Handle<Map> transition) {
+void NamedStoreHandlerCompiler::GenerateRestoreName(Handle<Name> name) {
   __ li(this->name(), Operand(name));
-  __ li(StoreTransitionDescriptor::MapRegister(), Operand(transition));
+}
+
+
+void NamedStoreHandlerCompiler::GenerateRestoreMap(Handle<Map> transition,
+                                                   Register scratch,
+                                                   Label* miss) {
+  Handle<WeakCell> cell = Map::WeakCellForMap(transition);
+  Register map_reg = StoreTransitionDescriptor::MapRegister();
+  DCHECK(!map_reg.is(scratch));
+  __ LoadWeakValue(map_reg, cell, miss);
+  if (transition->CanBeDeprecated()) {
+    __ lw(scratch, FieldMemOperand(map_reg, Map::kBitField3Offset));
+    __ And(at, scratch, Operand(Map::Deprecated::kMask));
+    __ Branch(miss, ne, at, Operand(zero_reg));
+  }
 }