Migrate instance of deprecated maps in HCheckMaps.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 5a113f7c9c652e2fab1370bd3bc80faa283a5af4..4fef16861c4efad94b9fe548f42456137898ebb3 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -4961,31 +4961,66 @@ void LCodeGen::DoCheckFunction(LCheckFunction* instr) {
 }
 
 
-void LCodeGen::DoCheckMapCommon(Register reg,
-                                Handle<Map> map,
-                                LInstruction* instr) {
-  Label success;
-  __ CompareMap(reg, map, &success);
-  DeoptimizeIf(not_equal, instr->environment());
-  __ bind(&success);
+void LCodeGen::DoDeferredInstanceMigration(LCheckMaps* instr, Register object) {
+  {
+    PushSafepointRegistersScope scope(this);
+    __ push(object);
+    CallRuntimeFromDeferred(Runtime::kMigrateInstance, 1, instr);
+    __ testq(rax, Immediate(kSmiTagMask));
+  }
+  DeoptimizeIf(zero, instr->environment());
 }
 
 
 void LCodeGen::DoCheckMaps(LCheckMaps* instr) {
+  class DeferredInstanceMigration: public LDeferredCode {

[danno, 2013/08/05 14:36:59]

Do you want this class here or in the outer scope somewhere? It seems like you
might want to use it for other stuff at some point. Otherwise, it probably
should just be called DeferredCheckMaps.

[Toon Verwaest, 2013/08/05 15:03:26]

Done.

+   public:
+    DeferredInstanceMigration(LCodeGen* codegen,
+                              LCheckMaps* instr,
+                              Register object)
+        : LDeferredCode(codegen), instr_(instr), object_(object) {
+      SetExit(check_maps());
+    }
+    virtual void Generate() {
+      codegen()->DoDeferredInstanceMigration(instr_, object_);
+    }
+    Label* check_maps() { return &check_maps_; }
+    virtual LInstruction* instr() { return instr_; }
+   private:
+    LCheckMaps* instr_;
+    Label check_maps_;
+    Register object_;
+  };
+
   if (instr->hydrogen()->CanOmitMapChecks()) return;
+
   LOperand* input = instr->value();
   ASSERT(input->IsRegister());
   Register reg = ToRegister(input);
 
-  Label success;
   SmallMapList* map_set = instr->hydrogen()->map_set();
+
+  DeferredInstanceMigration* deferred = NULL;
+  if (instr->hydrogen()->has_migration_target()) {
+    deferred = new(zone()) DeferredInstanceMigration(this, instr, reg);
+    __ bind(deferred->check_maps());
+  }
+
+  Label success;
   for (int i = 0; i < map_set->length() - 1; i++) {
     Handle<Map> map = map_set->at(i);
     __ CompareMap(reg, map, &success);
     __ j(equal, &success);
   }
+
   Handle<Map> map = map_set->last();
-  DoCheckMapCommon(reg, map, instr);
+  __ CompareMap(reg, map, &success);
+  if (instr->hydrogen()->has_migration_target()) {
+    __ j(not_equal, deferred->entry());
+  } else {
+    DeoptimizeIf(not_equal, instr->environment());
+  }
+
   __ bind(&success);
 }