Rename SloppyBlockWithEvalContextExtension to ContextExtension

The plan is to also use it for With and Catch scopes, so all kinds of
contexts have a pointer back to their ScopeInfo

R=neis@chromium.org,marja@chromium.org
BUG=v8:5215

Review-Url: https://codereview.chromium.org/2301913002
Cr-Commit-Position: refs/heads/master@{#39092}

src/contexts.cc

@@ -64,8 +64,8 @@ bool Context::is_declaration_context() {
   Object* ext = extension();
   // If we have the special extension, we immediately know it must be a
   // declaration scope. That's just a small performance shortcut.
-  return ext->IsSloppyBlockWithEvalContextExtension()
-      || ScopeInfo::cast(ext)->is_declaration_scope();
+  return ext->IsContextExtension() ||
+         ScopeInfo::cast(ext)->is_declaration_scope();
 }
 
 
@@ -93,8 +93,8 @@ JSObject* Context::extension_object() {
   HeapObject* object = extension();
   if (object->IsTheHole(GetIsolate())) return nullptr;
   if (IsBlockContext()) {
-    if (!object->IsSloppyBlockWithEvalContextExtension()) return nullptr;
-    object = SloppyBlockWithEvalContextExtension::cast(object)->extension();
+    if (!object->IsContextExtension()) return nullptr;
+    object = JSObject::cast(ContextExtension::cast(object)->extension());
   }
   DCHECK(object->IsJSContextExtensionObject() ||
          (IsNativeContext() && object->IsJSGlobalObject()));
@@ -112,9 +112,9 @@ JSReceiver* Context::extension_receiver() {
 ScopeInfo* Context::scope_info() {
   DCHECK(IsModuleContext() || IsScriptContext() || IsBlockContext());
   HeapObject* object = extension();
-  if (object->IsSloppyBlockWithEvalContextExtension()) {
+  if (object->IsContextExtension()) {
     DCHECK(IsBlockContext());
-    object = SloppyBlockWithEvalContextExtension::cast(object)->scope_info();
+    object = ContextExtension::cast(object)->scope_info();
   }
   return ScopeInfo::cast(object);
 }

src/contexts.h

@@ -298,8 +298,8 @@ class ScriptContextTable : public FixedArray {
 //
 // [ previous  ]  A pointer to the previous context.
 //
-// [ extension ]  A pointer to an extension JSObject, or "the hole". Used to
-//                implement 'with' statements and dynamic declarations
+// [ extension ]  A pointer to a ContextExtension object, or "the hole". Used
+//                to implement 'with' statements and dynamic declarations
 //                (through 'eval'). The object in a 'with' statement is
 //                stored in the extension slot of a 'with' context.
 //                Dynamically declared variables/functions are also added
@@ -308,8 +308,8 @@ class ScriptContextTable : public FixedArray {
 //                For script and block contexts, contains the respective
 //                ScopeInfo. For block contexts representing sloppy declaration
 //                block scopes, it may also be a struct being a
-//                SloppyBlockWithEvalContextExtension, pairing the ScopeInfo
-//                with an extension object.
+//                ContextExtension, pairing the ScopeInfo with an extension
+//                object.
 //
 // [ native_context ]  A pointer to the native context.
 //

src/factory.cc

@@ -102,14 +102,11 @@ Handle<PrototypeInfo> Factory::NewPrototypeInfo() {
   return result;
 }
 
-
-Handle<SloppyBlockWithEvalContextExtension>
-Factory::NewSloppyBlockWithEvalContextExtension(
-    Handle<ScopeInfo> scope_info, Handle<JSObject> extension) {
+Handle<ContextExtension> Factory::NewContextExtension(
+    Handle<ScopeInfo> scope_info, Handle<Object> extension) {
   DCHECK(scope_info->is_declaration_scope());
-  Handle<SloppyBlockWithEvalContextExtension> result =
-      Handle<SloppyBlockWithEvalContextExtension>::cast(
-          NewStruct(SLOPPY_BLOCK_WITH_EVAL_CONTEXT_EXTENSION_TYPE));
+  Handle<ContextExtension> result =
+      Handle<ContextExtension>::cast(NewStruct(CONTEXT_EXTENSION_TYPE));
   result->set_scope_info(*scope_info);
   result->set_extension(*extension);
   return result;

src/factory.h

@@ -64,10 +64,9 @@ class Factory final {
   // Create a new PrototypeInfo struct.
   Handle<PrototypeInfo> NewPrototypeInfo();
 
-  // Create a new SloppyBlockWithEvalContextExtension struct.
-  Handle<SloppyBlockWithEvalContextExtension>
-  NewSloppyBlockWithEvalContextExtension(Handle<ScopeInfo> scope_info,
-                                         Handle<JSObject> extension);
+  // Create a new ContextExtension struct.
+  Handle<ContextExtension> NewContextExtension(Handle<ScopeInfo> scope_info,
+                                               Handle<Object> extension);
 
   // Create a pre-tenured empty AccessorPair.
   Handle<AccessorPair> NewAccessorPair();

src/objects-debug.cc

@@ -911,10 +911,8 @@ void PrototypeInfo::PrototypeInfoVerify() {
   CHECK(validity_cell()->IsCell() || validity_cell()->IsSmi());
 }
 
-
-void SloppyBlockWithEvalContextExtension::
-    SloppyBlockWithEvalContextExtensionVerify() {
-  CHECK(IsSloppyBlockWithEvalContextExtension());
+void ContextExtension::ContextExtensionVerify() {
+  CHECK(IsContextExtension());
   VerifyObjectField(kScopeInfoOffset);
   VerifyObjectField(kExtensionOffset);
 }

src/objects-inl.h

@@ -5692,10 +5692,8 @@ ACCESSORS(PrototypeInfo, validity_cell, Object, kValidityCellOffset)
 SMI_ACCESSORS(PrototypeInfo, bit_field, kBitFieldOffset)
 BOOL_ACCESSORS(PrototypeInfo, bit_field, should_be_fast_map, kShouldBeFastBit)
 
-ACCESSORS(SloppyBlockWithEvalContextExtension, scope_info, ScopeInfo,
-          kScopeInfoOffset)
-ACCESSORS(SloppyBlockWithEvalContextExtension, extension, JSObject,
-          kExtensionOffset)
+ACCESSORS(ContextExtension, scope_info, ScopeInfo, kScopeInfoOffset)
+ACCESSORS(ContextExtension, extension, Object, kExtensionOffset)
 
 ACCESSORS(AccessorPair, getter, Object, kGetterOffset)
 ACCESSORS(AccessorPair, setter, Object, kSetterOffset)

src/objects-printer.cc

@@ -1136,10 +1136,8 @@ void PrototypeInfo::PrototypeInfoPrint(std::ostream& os) {  // NOLINT
   os << "\n";
 }
 
-
-void SloppyBlockWithEvalContextExtension::
-    SloppyBlockWithEvalContextExtensionPrint(std::ostream& os) {  // NOLINT
-  HeapObject::PrintHeader(os, "SloppyBlockWithEvalContextExtension");
+void ContextExtension::ContextExtensionPrint(std::ostream& os) {  // NOLINT
+  HeapObject::PrintHeader(os, "ContextExtension");
   os << "\n - scope_info: " << Brief(scope_info());
   os << "\n - extension: " << Brief(extension());
   os << "\n";

src/objects.h

@@ -395,7 +395,7 @@ const int kStubMinorKeyBits = kSmiValueSize - kStubMajorKeyBits - 1;
   V(ALIASED_ARGUMENTS_ENTRY_TYPE)                               \
   V(BOX_TYPE)                                                   \
   V(PROTOTYPE_INFO_TYPE)                                        \
-  V(SLOPPY_BLOCK_WITH_EVAL_CONTEXT_EXTENSION_TYPE)              \
+  V(CONTEXT_EXTENSION_TYPE)                                     \
                                                                 \
   V(FIXED_ARRAY_TYPE)                                           \
   V(FIXED_DOUBLE_ARRAY_TYPE)                                    \
@@ -513,9 +513,7 @@ const int kStubMinorKeyBits = kSmiValueSize - kStubMajorKeyBits - 1;
   V(DEBUG_INFO, DebugInfo, debug_info)                                       \
   V(BREAK_POINT_INFO, BreakPointInfo, break_point_info)                      \
   V(PROTOTYPE_INFO, PrototypeInfo, prototype_info)                           \
-  V(SLOPPY_BLOCK_WITH_EVAL_CONTEXT_EXTENSION,                                \
-    SloppyBlockWithEvalContextExtension,                                     \
-    sloppy_block_with_eval_context_extension)
+  V(CONTEXT_EXTENSION, ContextExtension, context_extension)
 
 // We use the full 8 bits of the instance_type field to encode heap object
 // instance types.  The high-order bit (bit 7) is set if the object is not a
@@ -689,7 +687,7 @@ enum InstanceType {
   TRANSITION_ARRAY_TYPE,
   PROPERTY_CELL_TYPE,
   PROTOTYPE_INFO_TYPE,
-  SLOPPY_BLOCK_WITH_EVAL_CONTEXT_EXTENSION_TYPE,
+  CONTEXT_EXTENSION_TYPE,
 
   // All the following types are subtypes of JSReceiver, which corresponds to
   // objects in the JS sense. The first and the last type in this range are
@@ -6653,28 +6651,29 @@ class PrototypeInfo : public Struct {
 
 
 // Pair used to store both a ScopeInfo and an extension object in the extension
-// slot of a block context. Needed in the rare case where a declaration block
-// scope (a "varblock" as used to desugar parameter destructuring) also contains
-// a sloppy direct eval. (In no other case both are needed at the same time.)
-class SloppyBlockWithEvalContextExtension : public Struct {
+// slot of a block, catch, or with context. Needed in the rare case where a
+// declaration block scope (a "varblock" as used to desugar parameter
+// destructuring) also contains a sloppy direct eval, or for with and catch
+// scopes. (In no other case both are needed at the same time.)
+class ContextExtension : public Struct {
  public:
   // [scope_info]: Scope info.
   DECL_ACCESSORS(scope_info, ScopeInfo)
   // [extension]: Extension object.
-  DECL_ACCESSORS(extension, JSObject)
+  DECL_ACCESSORS(extension, Object)
 
-  DECLARE_CAST(SloppyBlockWithEvalContextExtension)
+  DECLARE_CAST(ContextExtension)
 
   // Dispatched behavior.
-  DECLARE_PRINTER(SloppyBlockWithEvalContextExtension)
-  DECLARE_VERIFIER(SloppyBlockWithEvalContextExtension)
+  DECLARE_PRINTER(ContextExtension)
+  DECLARE_VERIFIER(ContextExtension)
 
   static const int kScopeInfoOffset = HeapObject::kHeaderSize;
   static const int kExtensionOffset = kScopeInfoOffset + kPointerSize;
   static const int kSize = kExtensionOffset + kPointerSize;
 
  private:
-  DISALLOW_IMPLICIT_CONSTRUCTORS(SloppyBlockWithEvalContextExtension);
+  DISALLOW_IMPLICIT_CONSTRUCTORS(ContextExtension);
 };
 
 

src/runtime/runtime-scopes.cc

@@ -294,9 +294,8 @@ Object* DeclareEvalHelper(Isolate* isolate, Handle<String> name,
       DCHECK(context->IsBlockContext());
       object = isolate->factory()->NewJSObject(
           isolate->context_extension_function());
-      Handle<HeapObject> extension =
-          isolate->factory()->NewSloppyBlockWithEvalContextExtension(
-              handle(context->scope_info()), object);
+      Handle<HeapObject> extension = isolate->factory()->NewContextExtension(
+          handle(context->scope_info()), object);
       context->set_extension(*extension);
     } else {
       object = handle(context->extension_object(), isolate);

src/types.cc

@@ -278,7 +278,7 @@ Type::bitset BitsetType::Lub(i::Map* map) {
     case CELL_TYPE:
     case WEAK_CELL_TYPE:
     case PROTOTYPE_INFO_TYPE:
-    case SLOPPY_BLOCK_WITH_EVAL_CONTEXT_EXTENSION_TYPE:
+    case CONTEXT_EXTENSION_TYPE:
       UNREACHABLE();
       return kNone;
   }

tools/v8heapconst.py

@@ -89,7 +89,7 @@ INSTANCE_TYPES = {
   163: "ALIASED_ARGUMENTS_ENTRY_TYPE",
   164: "BOX_TYPE",
   173: "PROTOTYPE_INFO_TYPE",
-  174: "SLOPPY_BLOCK_WITH_EVAL_CONTEXT_EXTENSION_TYPE",
+  174: "CONTEXT_EXTENSION_TYPE",
   167: "FIXED_ARRAY_TYPE",
   148: "FIXED_DOUBLE_ARRAY_TYPE",
   168: "SHARED_FUNCTION_INFO_TYPE",
@@ -232,7 +232,7 @@ KNOWN_MAPS = {
   0x09231: (165, "DebugInfoMap"),
   0x0925d: (166, "BreakPointInfoMap"),
   0x09289: (173, "PrototypeInfoMap"),
-  0x092b5: (174, "SloppyBlockWithEvalContextExtensionMap"),
+  0x092b5: (174, "ContextExtensionMap"),
 }
 
 # List of known V8 objects.