[strong] Implement strong property access semantics

src/hydrogen.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/hydrogen.h"
 
 #include <sstream>
 
 #include "src/v8.h"
 
@@ skipping 665 matching lines @@
 HConstant* HGraph::GetConstant1() {
   return GetConstant(&constant_1_, 1);
 }
 
 
 HConstant* HGraph::GetConstantMinus1() {
   return GetConstant(&constant_minus1_, -1);
 }
 
 
+HConstant* HGraph::GetConstantBool(bool value) {
+  return value ? GetConstantTrue() : GetConstantFalse();
+}
+
+
 #define DEFINE_GET_CONSTANT(Name, name, type, htype, boolean_value)            \
 HConstant* HGraph::GetConstant##Name() {                                       \
   if (!constant_##name##_.is_set()) {                                          \
     HConstant* constant = new(zone()) HConstant(                               \
         Unique<Object>::CreateImmovable(isolate()->factory()->name##_value()), \
         Unique<Map>::CreateImmovable(isolate()->factory()->type##_map()),      \
         false,                                                                 \
         Representation::Tagged(),                                              \
         htype,                                                                 \
         true,                                                                  \
@@ skipping 964 matching lines @@
   // hash = hash * 2057;
   hash = AddUncasted<HMul>(hash, Add<HConstant>(2057));
   hash->ClearFlag(HValue::kCanOverflow);
 
   // hash = hash ^ (hash >> 16);
   shifted_hash = AddUncasted<HShr>(hash, Add<HConstant>(16));
   return AddUncasted<HBitwise>(Token::BIT_XOR, hash, shifted_hash);
 }
 
 
-HValue* HGraphBuilder::BuildUncheckedDictionaryElementLoad(HValue* receiver,
-                                                           HValue* elements,
-                                                           HValue* key,
-                                                           HValue* hash) {
+HValue* HGraphBuilder::BuildUncheckedDictionaryElementLoad(
+    HValue* receiver, HValue* elements, HValue* key, HValue* hash,
+    LanguageMode language_mode) {
   HValue* capacity =
       Add<HLoadKeyed>(elements, Add<HConstant>(NameDictionary::kCapacityIndex),
                       nullptr, FAST_ELEMENTS);
 
   HValue* mask = AddUncasted<HSub>(capacity, graph()->GetConstant1());
   mask->ChangeRepresentation(Representation::Integer32());
   mask->ClearFlag(HValue::kCanOverflow);
 
   HValue* entry = hash;
   HValue* count = graph()->GetConstant1();
@@ skipping 22 matching lines @@
   HValue* candidate_key =
       Add<HLoadKeyed>(elements, key_index, nullptr, FAST_ELEMENTS);
   IfBuilder if_undefined(this);
   if_undefined.If<HCompareObjectEqAndBranch>(candidate_key,
                                              graph()->GetConstantUndefined());
   if_undefined.Then();
   {
     // element == undefined means "not found". Call the runtime.
     // TODO(jkummerow): walk the prototype chain instead.
     Add<HPushArguments>(receiver, key);
-    Push(Add<HCallRuntime>(isolate()->factory()->empty_string(),
-                           Runtime::FunctionForId(Runtime::kKeyedGetProperty),
-                           2));
+    Push(Add<HCallRuntime>(
+        isolate()->factory()->empty_string(),
+        Runtime::FunctionForId(is_strong(language_mode)
+                                   ? Runtime::kKeyedGetPropertyStrong
+                                   : Runtime::kKeyedGetProperty),
+        2));
   }
   if_undefined.Else();
   {
     IfBuilder if_match(this);
     if_match.If<HCompareObjectEqAndBranch>(candidate_key, key);
     if_match.Then();
     if_match.Else();
 
     // Update non-internalized string in the dictionary with internalized key?
     IfBuilder if_update_with_internalized(this);
@@ skipping 37 matching lines @@
     IfBuilder details_compare(this);
     details_compare.If<HCompareNumericAndBranch>(
         details, graph()->GetConstant0(), Token::EQ);
     details_compare.Then();
     HValue* result_index =
         AddUncasted<HAdd>(base_index, Add<HConstant>(start_offset + 1));
     result_index->ClearFlag(HValue::kCanOverflow);
     Push(Add<HLoadKeyed>(elements, result_index, nullptr, FAST_ELEMENTS));
     details_compare.Else();
     Add<HPushArguments>(receiver, key);
-    Push(Add<HCallRuntime>(isolate()->factory()->empty_string(),
-                           Runtime::FunctionForId(Runtime::kKeyedGetProperty),
-                           2));
+    Push(Add<HCallRuntime>(
+        isolate()->factory()->empty_string(),
+        Runtime::FunctionForId(is_strong(language_mode)
+                                   ? Runtime::kKeyedGetPropertyStrong
+                                   : Runtime::kKeyedGetProperty),
+        2));
     details_compare.End();
 
     found_key_match.Else();
     found_key_match.JoinContinuation(&return_or_loop_continuation);
   }
   if_undefined.JoinContinuation(&return_or_loop_continuation);
 
   IfBuilder return_or_loop(this, &return_or_loop_continuation);
   return_or_loop.Then();
   probe_loop.Break();
@@ skipping 4452 matching lines @@
   return false;
 }
 
 
 bool HOptimizedGraphBuilder::PropertyAccessInfo::CanAccessAsMonomorphic(
     SmallMapList* maps) {
   DCHECK(map_.is_identical_to(maps->first()));
   if (!CanAccessMonomorphic()) return false;
   STATIC_ASSERT(kMaxLoadPolymorphism == kMaxStorePolymorphism);
   if (maps->length() > kMaxLoadPolymorphism) return false;
-
   HObjectAccess access = HObjectAccess::ForMap();  // bogus default
   if (GetJSObjectFieldAccess(&access)) {
     for (int i = 1; i < maps->length(); ++i) {
       PropertyAccessInfo test_info(builder_, access_type_, maps->at(i), name_);
       HObjectAccess test_access = HObjectAccess::ForMap();  // bogus default
       if (!test_info.GetJSObjectFieldAccess(&test_access)) return false;
       if (!access.Equals(test_access)) return false;
     }
     return true;
   }
-
   if (GetJSArrayBufferViewFieldAccess(&access)) {
     for (int i = 1; i < maps->length(); ++i) {
       PropertyAccessInfo test_info(builder_, access_type_, maps->at(i), name_);
       HObjectAccess test_access = HObjectAccess::ForMap();  // bogus default
       if (!test_info.GetJSArrayBufferViewFieldAccess(&test_access)) {
         return false;
       }
       if (!access.Equals(test_access)) return false;
     }
     return true;
@@ skipping 61 matching lines @@
   }
 
   HValue* checked_holder = checked_object;
   if (info->has_holder()) {
     Handle<JSObject> prototype(JSObject::cast(info->map()->prototype()));
     checked_holder = BuildCheckPrototypeMaps(prototype, info->holder());
   }
 
   if (!info->IsFound()) {
     DCHECK(info->IsLoad());
-    return graph()->GetConstantUndefined();
+    if (is_strong(function_language_mode())) {
+      return New<HCallRuntime>(
+          isolate()->factory()->empty_string(),
+          Runtime::FunctionForId(Runtime::kThrowStrongModeImplicitConversion),
+          0);
+    } else {
+      return graph()->GetConstantUndefined();
+    }
   }
 
   if (info->IsData()) {
     if (info->IsLoad()) {
       return BuildLoadNamedField(info, checked_holder);
     } else {
       return BuildStoreNamedField(info, checked_object, value);
     }
   }
 
@@ skipping 676 matching lines @@
     Handle<TypeFeedbackVector> vector =
         handle(current_feedback_vector(), isolate());
     FeedbackVectorICSlot slot = expr->AsProperty()->PropertyFeedbackSlot();
 
     if (!expr->AsProperty()->key()->IsPropertyName()) {
       // It's possible that a keyed load of a constant string was converted
       // to a named load. Here, at the last minute, we need to make sure to
       // use a generic Keyed Load if we are using the type vector, because
       // it has to share information with full code.
       HConstant* key = Add<HConstant>(name);
-      HLoadKeyedGeneric* result =
-          New<HLoadKeyedGeneric>(object, key, PREMONOMORPHIC);
+      HLoadKeyedGeneric* result = New<HLoadKeyedGeneric>(
+          object, key, function_language_mode(), PREMONOMORPHIC);
       result->SetVectorAndSlot(vector, slot);
       return result;
     }
 
-    HLoadNamedGeneric* result =
-        New<HLoadNamedGeneric>(object, name, PREMONOMORPHIC);
+    HLoadNamedGeneric* result = New<HLoadNamedGeneric>(
+        object, name, function_language_mode(), PREMONOMORPHIC);
     result->SetVectorAndSlot(vector, slot);
     return result;
   } else {
     return New<HStoreNamedGeneric>(object, name, value,
                                    function_language_mode(), PREMONOMORPHIC);
   }
 }
 
 
 
 HInstruction* HOptimizedGraphBuilder::BuildKeyedGeneric(
     PropertyAccessType access_type,
     Expression* expr,
     HValue* object,
     HValue* key,
     HValue* value) {
   if (access_type == LOAD) {
     InlineCacheState initial_state = expr->AsProperty()->GetInlineCacheState();
-    HLoadKeyedGeneric* result =
-        New<HLoadKeyedGeneric>(object, key, initial_state);
+    HLoadKeyedGeneric* result = New<HLoadKeyedGeneric>(
+        object, key, function_language_mode(), initial_state);
     // HLoadKeyedGeneric with vector ics benefits from being encoded as
     // MEGAMORPHIC because the vector/slot combo becomes unnecessary.
     if (initial_state != MEGAMORPHIC) {
       // We need to pass vector information.
       Handle<TypeFeedbackVector> vector =
           handle(current_feedback_vector(), isolate());
       FeedbackVectorICSlot slot = expr->AsProperty()->PropertyFeedbackSlot();
       result->SetVectorAndSlot(vector, slot);
     }
     return result;
@@ skipping 2270 matching lines @@
     ComputeReceiverTypes(expr, receiver, &maps, zone());
 
     if (prop->key()->IsPropertyName() && maps->length() > 0) {
       Handle<String> name = prop->key()->AsLiteral()->AsPropertyName();
       PropertyAccessInfo info(this, LOAD, maps->first(), name);
       if (!info.CanAccessAsMonomorphic(maps)) {
         HandlePolymorphicCallNamed(expr, receiver, maps, name);
         return;
       }
     }
-
     HValue* key = NULL;
     if (!prop->key()->IsPropertyName()) {
       CHECK_ALIVE(VisitForValue(prop->key()));
       key = Pop();
     }
 
     CHECK_ALIVE(PushLoad(prop, receiver, key));
     HValue* function = Pop();
 
     if (function->IsConstant() &&
@@ skipping 1420 matching lines @@
   // Only the stub is allowed to call into the runtime, since otherwise we would
   // inline several instructions (including the two pushes) for every tagged
   // operation in optimized code, which is more expensive, than a stub call.
   if (graph()->info()->IsStub() && is_non_primitive) {
     HValue* function =
         AddLoadJSBuiltin(BinaryOpIC::TokenToJSBuiltin(op, strength));
     Add<HPushArguments>(left, right);
     instr = AddUncasted<HInvokeFunction>(function, 2);
   } else {
     if (is_strong(strength) && Token::IsBitOp(op)) {
+      // TODO(conradw): This is not efficient, but is necessary to prevent
+      // conversion of oddball values to numbers in strong mode. It would be
+      // better to prevent the conversion rather than adding a runtime check.
       IfBuilder if_builder(this);
       if_builder.If<HHasInstanceTypeAndBranch>(left, ODDBALL_TYPE);
       if_builder.OrIf<HHasInstanceTypeAndBranch>(right, ODDBALL_TYPE);
       if_builder.Then();
       Add<HCallRuntime>(
           isolate()->factory()->empty_string(),
           Runtime::FunctionForId(Runtime::kThrowStrongModeImplicitConversion),
           0);
       if (!graph()->info()->IsStub()) {
         Add<HSimulate>(opt_id, REMOVABLE_SIMULATE);
@@ skipping 2415 matching lines @@
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8