Loads and stores to global vars are now made via property cell shortcuts installed into parent scri…

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 321 matching lines @@
 
 
 void HBasicBlock::RegisterPredecessor(HBasicBlock* pred) {
   if (HasPredecessor()) {
     // Only loop header blocks can have a predecessor added after
     // instructions have been added to the block (they have phis for all
     // values in the environment, these phis may be eliminated later).
     DCHECK(IsLoopHeader() || first_ == NULL);
     HEnvironment* incoming_env = pred->last_environment();
     if (IsLoopHeader()) {
-      DCHECK(phis()->length() == incoming_env->length());
+      DCHECK_EQ(phis()->length(), incoming_env->length());
       for (int i = 0; i < phis_.length(); ++i) {
         phis_[i]->AddInput(incoming_env->values()->at(i));
       }
     } else {
       last_environment()->AddIncomingEdge(this, pred->last_environment());
     }
   } else if (!HasEnvironment() && !IsFinished()) {
     DCHECK(!IsLoopHeader());
     SetInitialEnvironment(pred->last_environment()->Copy());
   }
@@ skipping 637 matching lines @@
     *else_continuation = else_record->block_;
   }
   MergeAtJoinBlock* then_record = else_record->next_;
   if (then_continuation != NULL) {
     *then_continuation = then_record->block_;
   }
   DCHECK(then_record->next_ == NULL);
 }
 
 
+void HGraphBuilder::IfBuilder::EndUnreachable() {
+  if (captured_) return;
+  Finish();
+  builder()->set_current_block(nullptr);
+}
+
+
 void HGraphBuilder::IfBuilder::End() {
   if (captured_) return;
   Finish();
 
   int total_merged_blocks = normal_merge_at_join_block_count_ +
     deopt_merge_at_join_block_count_;
   DCHECK(total_merged_blocks >= 1);
   HBasicBlock* merge_block =
       total_merged_blocks == 1 ? NULL : builder()->graph()->CreateBasicBlock();
 
@@ skipping 2117 matching lines @@
     // This smi value is reset to zero after every gc, overflow isn't a problem
     // since the counter is bounded by the new space size.
     memento_create_count->ClearFlag(HValue::kCanOverflow);
     Add<HStoreNamedField>(
         allocation_site, HObjectAccess::ForAllocationSiteOffset(
             AllocationSite::kPretenureCreateCountOffset), memento_create_count);
   }
 }
 
 
+HInstruction* HGraphBuilder::BuildGetNativeContext() {
+  // Get the global object, then the native context
+  HValue* global_object = Add<HLoadNamedField>(
+      context(), nullptr,
+      HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
+  return Add<HLoadNamedField>(global_object, nullptr,
+                              HObjectAccess::ForObservableJSObjectOffset(
+                                  GlobalObject::kNativeContextOffset));
+}
+
+
 HInstruction* HGraphBuilder::BuildGetNativeContext(HValue* closure) {
   // Get the global object, then the native context
   HInstruction* context = Add<HLoadNamedField>(
       closure, nullptr, HObjectAccess::ForFunctionContextPointer());
   HInstruction* global_object = Add<HLoadNamedField>(
       context, nullptr,
       HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
   HObjectAccess access = HObjectAccess::ForObservableJSObjectOffset(
       GlobalObject::kNativeContextOffset);
   return Add<HLoadNamedField>(global_object, nullptr, access);
 }
 
 
 HInstruction* HGraphBuilder::BuildGetScriptContext(int context_index) {
   HValue* native_context = BuildGetNativeContext();
   HValue* script_context_table = Add<HLoadNamedField>(
       native_context, nullptr,
       HObjectAccess::ForContextSlot(Context::SCRIPT_CONTEXT_TABLE_INDEX));
   return Add<HLoadNamedField>(script_context_table, nullptr,
                               HObjectAccess::ForScriptContext(context_index));
 }
 
 
-HInstruction* HGraphBuilder::BuildGetNativeContext() {
-  // Get the global object, then the native context
-  HValue* global_object = Add<HLoadNamedField>(
-      context(), nullptr,
-      HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
-  return Add<HLoadNamedField>(global_object, nullptr,
-                              HObjectAccess::ForObservableJSObjectOffset(
-                                  GlobalObject::kNativeContextOffset));
+HValue* HGraphBuilder::BuildGetParentContext(HValue* depth, int depth_value) {
+  HValue* script_context = context();
+  if (depth != NULL) {
+    HValue* zero = graph()->GetConstant0();
+
+    Push(script_context);
+    Push(depth);
+
+    LoopBuilder loop(this);
+    loop.BeginBody(2);  // Drop script_context and depth from last environment
+                        // to appease live range building without simulates.
+    depth = Pop();
+    script_context = Pop();
+
+    script_context = Add<HLoadNamedField>(
+        script_context, nullptr,
+        HObjectAccess::ForContextSlot(Context::PREVIOUS_INDEX));
+    depth = AddUncasted<HSub>(depth, graph()->GetConstant1());
+    depth->ClearFlag(HValue::kCanOverflow);
+
+    IfBuilder if_break(this);
+    if_break.If<HCompareNumericAndBranch, HValue*>(depth, zero, Token::EQ);
+    if_break.Then();
+    {
+      Push(script_context);  // The result.
+      loop.Break();
+    }
+    if_break.Else();
+    {
+      Push(script_context);
+      Push(depth);
+    }
+    loop.EndBody();
+    if_break.End();
+
+    script_context = Pop();
+  } else if (depth_value > 0) {
+    // Unroll the above loop.
+    for (int i = 0; i < depth_value; i++) {
+      script_context = Add<HLoadNamedField>(
+          script_context, nullptr,
+          HObjectAccess::ForContextSlot(Context::PREVIOUS_INDEX));
+    }
+  }
+  return script_context;
 }
 
 
 HInstruction* HGraphBuilder::BuildGetArrayFunction() {
   HInstruction* native_context = BuildGetNativeContext();
   HInstruction* index =
       Add<HConstant>(static_cast<int32_t>(Context::ARRAY_FUNCTION_INDEX));
   return Add<HLoadKeyed>(native_context, index, nullptr, FAST_ELEMENTS);
 }
 
@@ skipping 10067 matching lines @@
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8