Use a different map to distinguish eval contexts

src/compiler/js-create-lowering.cc

 // Copyright 2016 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/compiler/js-create-lowering.h"
 
 #include "src/allocation-site-scopes.h"
 #include "src/code-factory.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/access-builder.h"
@@ skipping 197 matching lines @@
       return ReduceJSCreateArray(node);
     case IrOpcode::kJSCreateClosure:
       return ReduceJSCreateClosure(node);
     case IrOpcode::kJSCreateIterResultObject:
       return ReduceJSCreateIterResultObject(node);
     case IrOpcode::kJSCreateLiteralArray:
     case IrOpcode::kJSCreateLiteralObject:
       return ReduceJSCreateLiteral(node);
     case IrOpcode::kJSCreateFunctionContext:
       return ReduceJSCreateFunctionContext(node);
+    case IrOpcode::kJSCreateEvalContext:
+      return ReduceJSCreateEvalContext(node);
     case IrOpcode::kJSCreateWithContext:
       return ReduceJSCreateWithContext(node);
     case IrOpcode::kJSCreateCatchContext:
       return ReduceJSCreateCatchContext(node);
     case IrOpcode::kJSCreateBlockContext:
       return ReduceJSCreateBlockContext(node);
     default:
       break;
   }
   return NoChange();
@@ skipping 548 matching lines @@
       a.Store(AccessBuilder::ForContextSlot(i), jsgraph()->UndefinedConstant());
     }
     RelaxControls(node);
     a.FinishAndChange(node);
     return Changed(node);
   }
 
   return NoChange();
 }
 
+Reduction JSCreateLowering::ReduceJSCreateEvalContext(Node* node) {
+  DCHECK_EQ(IrOpcode::kJSCreateEvalContext, node->opcode());
+  int slot_count = OpParameter<int>(node->op());
+  Node* const closure = NodeProperties::GetValueInput(node, 0);
+
+  // Use inline allocation for function contexts up to a size limit.
+  if (slot_count < kFunctionContextAllocationLimit) {
+    // JSCreateFunctionContext[slot_count < limit]](fun)
+    Node* effect = NodeProperties::GetEffectInput(node);
+    Node* control = NodeProperties::GetControlInput(node);
+    Node* context = NodeProperties::GetContextInput(node);
+    Node* extension = jsgraph()->TheHoleConstant();
+    AllocationBuilder a(jsgraph(), effect, control);
+    STATIC_ASSERT(Context::MIN_CONTEXT_SLOTS == 4);  // Ensure fully covered.
+    int context_length = slot_count + Context::MIN_CONTEXT_SLOTS;
+    a.AllocateArray(context_length, factory()->eval_context_map());
+    a.Store(AccessBuilder::ForContextSlot(Context::CLOSURE_INDEX), closure);
+    a.Store(AccessBuilder::ForContextSlot(Context::PREVIOUS_INDEX), context);
+    a.Store(AccessBuilder::ForContextSlot(Context::EXTENSION_INDEX), extension);
+    a.Store(AccessBuilder::ForContextSlot(Context::NATIVE_CONTEXT_INDEX),
+            jsgraph()->HeapConstant(native_context()));
+    for (int i = Context::MIN_CONTEXT_SLOTS; i < context_length; ++i) {
+      a.Store(AccessBuilder::ForContextSlot(i), jsgraph()->UndefinedConstant());
+    }
+    RelaxControls(node);
+    a.FinishAndChange(node);
+    return Changed(node);
+  }
+
+  return NoChange();
+}
+
 Reduction JSCreateLowering::ReduceJSCreateWithContext(Node* node) {
   DCHECK_EQ(IrOpcode::kJSCreateWithContext, node->opcode());
   Handle<ScopeInfo> scope_info = OpParameter<Handle<ScopeInfo>>(node);
   Node* object = NodeProperties::GetValueInput(node, 0);
   Node* closure = NodeProperties::GetValueInput(node, 1);
   Node* effect = NodeProperties::GetEffectInput(node);
   Node* control = NodeProperties::GetControlInput(node);
   Node* context = NodeProperties::GetContextInput(node);
 
   AllocationBuilder aa(jsgraph(), effect, control);
@@ skipping 456 matching lines @@
   return jsgraph()->simplified();
 }
 
 MachineOperatorBuilder* JSCreateLowering::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8