Migrate instance of deprecated maps in HCheckMaps.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index b9eab45293befcf143e0bfa77abc8f347cc459b9..5c1c12528b61d92201839c6f33b141612e89fd56 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -1086,6 +1086,7 @@ class HValue: public ZoneObject {
   virtual HValue* Canonicalize() { return this; }
 
   bool Equals(HValue* other);
+  virtual int CompareOperandCount() { return OperandCount(); }

[danno, 2013/08/05 10:07:36]

See comment below about storing the context explicitly.

[Toon Verwaest, 2013/08/05 11:32:13]

Done.

   virtual intptr_t Hashcode();
 
   // Compute unique ids upfront that is safe wrt GC and parallel recompilation.
@@ -2866,7 +2867,7 @@ class HLoadExternalArrayPointer: public HUnaryOperation {
 };
 
 
-class HCheckMaps: public HTemplateInstruction<2> {
+class HCheckMaps: public HTemplateInstruction<3> {

[danno, 2013/08/05 10:07:36]

It seems to me this class would be much cleaner if you just stored the context
internally in a hand-allocated field of the class rather than one of the
built-in fields of the HTemplateInstruction<>

[Toon Verwaest, 2013/08/05 11:32:13]

Done.

  public:
   static HCheckMaps* New(Zone* zone, HValue* context, HValue* value,
                          Handle<Map> map, CompilationInfo* info,
@@ -2874,9 +2875,11 @@ class HCheckMaps: public HTemplateInstruction<2> {
   static HCheckMaps* New(Zone* zone, HValue* context,
                          HValue* value, SmallMapList* maps,
                          HValue *typecheck = NULL) {
-    HCheckMaps* check_map = new(zone) HCheckMaps(value, zone, typecheck);
+    HCheckMaps* check_map = new(zone) HCheckMaps(
+        context, value, zone, typecheck);
     for (int i = 0; i < maps->length(); i++) {
       check_map->map_set_.Add(maps->at(i), zone);
+      check_map->has_migration_target_ |= maps->at(i)->is_migration_target();
     }
     check_map->map_set_.Sort();
     return check_map;
@@ -2893,13 +2896,19 @@ class HCheckMaps: public HTemplateInstruction<2> {
   virtual void PrintDataTo(StringStream* stream);
 
   HValue* value() { return OperandAt(0); }
+  HValue* context() { return OperandAt(2); }
   SmallMapList* map_set() { return &map_set_; }
 
+  bool has_migration_target() {
+    return has_migration_target_;
+  }
+
   virtual void FinalizeUniqueValueId();
 
   DECLARE_CONCRETE_INSTRUCTION(CheckMaps)
 
  protected:
+  virtual int CompareOperandCount() { return OperandCount() - 1; }
   virtual bool DataEquals(HValue* other) {
     ASSERT_EQ(map_set_.length(), map_unique_ids_.length());
     HCheckMaps* b = HCheckMaps::cast(other);
@@ -2917,13 +2926,14 @@ class HCheckMaps: public HTemplateInstruction<2> {
 
  private:
   // Clients should use one of the static New* methods above.
-  HCheckMaps(HValue* value, Zone *zone, HValue* typecheck)
-      : HTemplateInstruction<2>(value->type()),
-        omit_(false), map_unique_ids_(0, zone) {
+  HCheckMaps(HValue* context, HValue* value, Zone *zone, HValue* typecheck)
+      : HTemplateInstruction<3>(value->type()),
+        omit_(false), has_migration_target_(false), map_unique_ids_(0, zone) {
     SetOperandAt(0, value);
     // Use the object value for the dependency if NULL is passed.
     // TODO(titzer): do GVN flags already express this dependency?
     SetOperandAt(1, typecheck != NULL ? typecheck : value);
+    SetOperandAt(2, context);
     set_representation(Representation::Tagged());
     SetFlag(kUseGVN);
     SetFlag(kTrackSideEffectDominators);
@@ -2941,6 +2951,7 @@ class HCheckMaps: public HTemplateInstruction<2> {
   }
 
   bool omit_;
+  bool has_migration_target_;
   SmallMapList map_set_;
   ZoneList<UniqueValueId> map_unique_ids_;
 };