RFC: Switch to ast ids (instead of positions) for type feedback.

src/type-info.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 53 matching lines @@
 
 
 void TypeFeedbackOracle::Initialize(Handle<Code> code) {
   ASSERT(map_.is_null());  // Only initialize once.
   map_ = Factory::NewJSObject(Top::object_function());
   PopulateMap(code);
 }
 
 
 bool TypeFeedbackOracle::LoadIsMonomorphic(Property* expr) {
-  return IsMonomorphic(expr->position());
+  return IsMonomorphic(expr->id());
 }
 
 
 bool TypeFeedbackOracle:: StoreIsMonomorphic(Assignment* expr) {
-  return IsMonomorphic(expr->position());
+  return IsMonomorphic(expr->id());
 }
 
 
 bool TypeFeedbackOracle::CallIsMonomorphic(Call* expr) {
-  return IsMonomorphic(expr->position());
+  return IsMonomorphic(expr->id());
 }
 
 
 Handle<Map> TypeFeedbackOracle::LoadMonomorphicReceiverType(Property* expr) {
   ASSERT(LoadIsMonomorphic(expr));
-  return Handle<Map>::cast(GetElement(map_, expr->position()));
+  return Handle<Map>::cast(GetElement(map_, expr->id()));
 }
 
 
 Handle<Map> TypeFeedbackOracle::StoreMonomorphicReceiverType(Assignment* expr) {
   ASSERT(StoreIsMonomorphic(expr));
-  return Handle<Map>::cast(GetElement(map_, expr->position()));
+  return Handle<Map>::cast(GetElement(map_, expr->id()));
 }
 
 
 Handle<Map> TypeFeedbackOracle::CallMonomorphicReceiverType(Call* expr) {
   ASSERT(CallIsMonomorphic(expr));
-  return Handle<Map>::cast(GetElement(map_, expr->position()));
+  return Handle<Map>::cast(GetElement(map_, expr->id()));
 }
 
 
 ZoneMapList* TypeFeedbackOracle::LoadReceiverTypes(Property* expr,
                                                    Handle<String> name) {
   Code::Flags flags = Code::ComputeMonomorphicFlags(Code::LOAD_IC, NORMAL);
-  return CollectReceiverTypes(expr->position(), name, flags);
+  return CollectReceiverTypes(expr->id(), name, flags);
 }
 
 
 ZoneMapList* TypeFeedbackOracle::StoreReceiverTypes(Assignment* expr,
                                                     Handle<String> name) {
   Code::Flags flags = Code::ComputeMonomorphicFlags(Code::STORE_IC, NORMAL);
-  return CollectReceiverTypes(expr->position(), name, flags);
+  return CollectReceiverTypes(expr->id(), name, flags);
 }
 
 
 ZoneMapList* TypeFeedbackOracle::CallReceiverTypes(Call* expr,
                                                    Handle<String> name) {
   int arity = expr->arguments()->length();
   Code::Flags flags = Code::ComputeMonomorphicFlags(
       Code::CALL_IC, NORMAL, OWN_MAP, NOT_IN_LOOP, arity);
-  return CollectReceiverTypes(expr->position(), name, flags);
+  return CollectReceiverTypes(expr->id(), name, flags);
 }
 
 
 bool TypeFeedbackOracle::LoadIsBuiltin(Property* expr, Builtins::Name id) {
-  Handle<Object> object = GetElement(map_, expr->position());
+  Handle<Object> object = GetElement(map_, expr->id());
   return *object == Builtins::builtin(id);
 }
 
 
 TypeInfo TypeFeedbackOracle::CompareType(CompareOperation* expr, Side side) {
-  Handle<Object> object = GetElement(map_, expr->position());
+  Handle<Object> object = GetElement(map_, expr->id());
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
   if (!code->is_compare_ic_stub()) return unknown;
 
   CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
   switch (state) {
     case CompareIC::UNINITIALIZED:
     case CompareIC::SMIS:
       return TypeInfo::Smi();
     case CompareIC::HEAP_NUMBERS:
       return TypeInfo::Number();
     case CompareIC::OBJECTS:
       // TODO(kasperl): We really need a type for JS objects here.
       return TypeInfo::NonPrimitive();
     case CompareIC::GENERIC:
     default:
       return unknown;
   }
 }
 
 
 TypeInfo TypeFeedbackOracle::BinaryType(BinaryOperation* expr, Side side) {
-  Handle<Object> object = GetElement(map_, expr->position());
+  Handle<Object> object = GetElement(map_, expr->id());
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
   if (code->is_binary_op_stub()) {
     BinaryOpIC::TypeInfo type = static_cast<BinaryOpIC::TypeInfo>(
         code->binary_op_type());
     switch (type) {
       case BinaryOpIC::UNINIT_OR_SMI:
         return TypeInfo::Smi();
       case BinaryOpIC::DEFAULT:
@@ skipping 37 matching lines @@
       case TRBinaryOpIC::GENERIC:
         return unknown;
      default:
         return unknown;
     }
   }
   return unknown;
 }
 
 TypeInfo TypeFeedbackOracle::SwitchType(CaseClause* clause) {
-  Handle<Object> object = GetElement(map_, clause->position());
+  Handle<Object> object = GetElement(map_, clause->label()->id());
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
   if (!code->is_compare_ic_stub()) return unknown;
 
   CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
   switch (state) {
     case CompareIC::UNINITIALIZED:
     case CompareIC::SMIS:
       return TypeInfo::Smi();
     case CompareIC::HEAP_NUMBERS:
       return TypeInfo::Number();
     case CompareIC::OBJECTS:
       // TODO(kasperl): We really need a type for JS objects here.
       return TypeInfo::NonPrimitive();
     case CompareIC::GENERIC:
     default:
       return unknown;
   }
 }
 
 
 
-ZoneMapList* TypeFeedbackOracle::CollectReceiverTypes(int position,
+ZoneMapList* TypeFeedbackOracle::CollectReceiverTypes(AstId id,
                                                       Handle<String> name,
                                                       Code::Flags flags) {
-  Handle<Object> object = GetElement(map_, position);
+  Handle<Object> object = GetElement(map_, id);
   if (object->IsUndefined()) return NULL;
 
   if (*object == Builtins::builtin(Builtins::StoreIC_GlobalProxy)) {
     // TODO(fschneider): We could collect the maps and signal that
     // we need a generic store (or load) here.
     ASSERT(Handle<Code>::cast(object)->ic_state() == MEGAMORPHIC);
     return NULL;
   } else if (object->IsMap()) {
     ZoneMapList* types = new ZoneMapList(1);
     types->Add(Handle<Map>::cast(object));
     return types;
   } else if (Handle<Code>::cast(object)->ic_state() == MEGAMORPHIC) {
     ZoneMapList* types = new ZoneMapList(4);
     ASSERT(object->IsCode());
     StubCache::CollectMatchingMaps(types, *name, flags);
     return types->length() > 0 ? types : NULL;
   } else {
     return NULL;
   }
 }
 
 
 void TypeFeedbackOracle::PopulateMap(Handle<Code> code) {
   HandleScope scope;
 
   const int kInitialCapacity = 16;
   List<int> code_positions(kInitialCapacity);
-  List<int> source_positions(kInitialCapacity);
-  CollectPositions(*code, &code_positions, &source_positions);
+  List<AstId> ast_ids(kInitialCapacity);
+  CollectIds(*code, &code_positions, &ast_ids);
 
-  int length = code_positions.length();
-  ASSERT(source_positions.length() == length);
+  const int length = code_positions.length();
+  ASSERT(ast_ids.length() == length);
   for (int i = 0; i < length; i++) {
     RelocInfo info(code->instruction_start() + code_positions[i],
                    RelocInfo::CODE_TARGET, 0);
     Handle<Code> target(Code::GetCodeFromTargetAddress(info.target_address()));
-    int position = source_positions[i];
+    AstId id = ast_ids[i];
     InlineCacheState state = target->ic_state();
     Code::Kind kind = target->kind();
     if (kind == Code::BINARY_OP_IC ||
         kind == Code::TYPE_RECORDING_BINARY_OP_IC ||
         kind == Code::COMPARE_IC) {
-      // TODO(kasperl): Avoid having multiple ICs with the same
-      // position by making sure that we have position information
-      // recorded for all binary ICs.
-      if (GetElement(map_, position)->IsUndefined()) {
-        SetElement(map_, position, target);
-      }
+      SetInfo(id, target);
     } else if (state == MONOMORPHIC) {
       Handle<Map> map = Handle<Map>(target->FindFirstMap());
       if (*map == NULL) {
-        SetElement(map_, position, target);
+        SetInfo(id, target);
       } else {
-        SetElement(map_, position, map);
+        SetInfo(id, map);
       }
     } else if (state == MEGAMORPHIC) {
-      SetElement(map_, position, target);
+      SetInfo(id, target);
     }
   }
 }
 
 
-void TypeFeedbackOracle::CollectPositions(Code* code,
-                                          List<int>* code_positions,
-                                          List<int>* source_positions) {
+void TypeFeedbackOracle::CollectIds(Code* code,
+                                    List<int>* code_positions,
+                                    List<AstId>* ast_ids) {
   AssertNoAllocation no_allocation;
-  int position = 0;
-  // Because the ICs we use for global variables access in the full
-  // code generator do not have any meaningful positions, we avoid
-  // collecting those by filtering out contextual code targets.
-  int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
-      RelocInfo::kPositionMask;
+  int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET_WITH_ID);
   for (RelocIterator it(code, mask); !it.done(); it.next()) {
     RelocInfo* info = it.rinfo();
-    RelocInfo::Mode mode = info->rmode();
-    if (RelocInfo::IsCodeTarget(mode)) {
-      Code* target = Code::GetCodeFromTargetAddress(info->target_address());
-      if (target->is_inline_cache_stub()) {
-        InlineCacheState state = target->ic_state();
-        Code::Kind kind = target->kind();
-        if (kind == Code::BINARY_OP_IC) {
-          if (target->binary_op_type() == BinaryOpIC::GENERIC) continue;
-        } else if (kind == Code::TYPE_RECORDING_BINARY_OP_IC) {
-          if (target->type_recording_binary_op_type() ==
-              TRBinaryOpIC::GENERIC) {
-            continue;
-          }
-        } else if (kind == Code::COMPARE_IC) {
-          if (target->compare_state() == CompareIC::GENERIC) continue;
-        } else {
-          if (kind == Code::CALL_IC && state == MONOMORPHIC &&
-              target->check_type() != RECEIVER_MAP_CHECK) continue;
-          if (state != MONOMORPHIC && state != MEGAMORPHIC) continue;
+    Code* target = Code::GetCodeFromTargetAddress(info->target_address());
+    if (target->is_inline_cache_stub()) {
+      InlineCacheState state = target->ic_state();
+      Code::Kind kind = target->kind();
+      if (kind == Code::BINARY_OP_IC) {
+        if (target->binary_op_type() == BinaryOpIC::GENERIC) continue;
+      } else if (kind == Code::TYPE_RECORDING_BINARY_OP_IC) {
+        if (target->type_recording_binary_op_type() ==
+            TRBinaryOpIC::GENERIC) {
+          continue;
         }
-        code_positions->Add(
-            static_cast<int>(info->pc() - code->instruction_start()));
-        source_positions->Add(position);
+      } else if (kind == Code::COMPARE_IC) {
+        if (target->compare_state() == CompareIC::GENERIC) continue;
+      } else {
+        if (kind == Code::CALL_IC && state == MONOMORPHIC &&
+            target->check_type() != RECEIVER_MAP_CHECK) continue;
+        if (state != MONOMORPHIC && state != MEGAMORPHIC) continue;
       }
-    } else {
-      ASSERT(RelocInfo::IsPosition(mode));
-      position = static_cast<int>(info->data());
+      code_positions->Add(
+          static_cast<int>(info->pc() - code->instruction_start()));
+      ast_ids->Add(static_cast<AstId>(info->data()));
     }
   }
 }
 
+
+void TypeFeedbackOracle::SetInfo(AstId id, Handle<Object> info) {
+  ASSERT(GetElement(map_, id)->IsUndefined());
+  SetElement(map_, id, info);
+}
+
 } }  // namespace v8::internal