Remove strong mode support from Scope and Variable

src/ast/scopeinfo.cc

 // Copyright 2011 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/ast/scopeinfo.h"
 
 #include <stdlib.h>
 
 #include "src/ast/scopes.h"
 #include "src/bootstrapper.h"
 
 namespace v8 {
 namespace internal {
 
 
 Handle<ScopeInfo> ScopeInfo::Create(Isolate* isolate, Zone* zone,
                                     Scope* scope) {
   // Collect stack and context locals.
   ZoneList<Variable*> stack_locals(scope->StackLocalCount(), zone);
   ZoneList<Variable*> context_locals(scope->ContextLocalCount(), zone);
   ZoneList<Variable*> context_globals(scope->ContextGlobalCount(), zone);
-  ZoneList<Variable*> strong_mode_free_variables(0, zone);
 
   scope->CollectStackAndContextLocals(&stack_locals, &context_locals,
-                                      &context_globals,
-                                      &strong_mode_free_variables);
+                                      &context_globals);
   const int stack_local_count = stack_locals.length();
   const int context_local_count = context_locals.length();
   const int context_global_count = context_globals.length();
-  const int strong_mode_free_variable_count =
-      strong_mode_free_variables.length();
   // Make sure we allocate the correct amount.
   DCHECK_EQ(scope->ContextLocalCount(), context_local_count);
   DCHECK_EQ(scope->ContextGlobalCount(), context_global_count);
 
   // Determine use and location of the "this" binding if it is present.
   VariableAllocationInfo receiver_info;
   if (scope->has_this_declaration()) {
     Variable* var = scope->receiver();
     if (!var->is_used()) {
       receiver_info = UNUSED;
@@ skipping 28 matching lines @@
     function_variable_mode = VAR;
   }
   DCHECK(context_global_count == 0 || scope->scope_type() == SCRIPT_SCOPE);
 
   const bool has_function_name = function_name_info != NONE;
   const bool has_receiver = receiver_info == STACK || receiver_info == CONTEXT;
   const int parameter_count = scope->num_parameters();
   const int length = kVariablePartIndex + parameter_count +
                      (1 + stack_local_count) + 2 * context_local_count +
                      2 * context_global_count +
-                     3 * strong_mode_free_variable_count +
                      (has_receiver ? 1 : 0) + (has_function_name ? 2 : 0);
 
   Factory* factory = isolate->factory();
   Handle<ScopeInfo> scope_info = factory->NewScopeInfo(length);
 
   bool has_simple_parameters =
       scope->is_function_scope() && scope->has_simple_parameters();
 
   // Encode the flags.
   int flags = ScopeTypeField::encode(scope->scope_type()) |
               CallsEvalField::encode(scope->calls_eval()) |
               LanguageModeField::encode(scope->language_mode()) |
               DeclarationScopeField::encode(scope->is_declaration_scope()) |
               ReceiverVariableField::encode(receiver_info) |
               HasNewTargetField::encode(has_new_target) |
               FunctionVariableField::encode(function_name_info) |
               FunctionVariableMode::encode(function_variable_mode) |
               AsmModuleField::encode(scope->asm_module()) |
               AsmFunctionField::encode(scope->asm_function()) |
               HasSimpleParametersField::encode(has_simple_parameters) |
               FunctionKindField::encode(scope->function_kind());
   scope_info->SetFlags(flags);
   scope_info->SetParameterCount(parameter_count);
   scope_info->SetStackLocalCount(stack_local_count);
   scope_info->SetContextLocalCount(context_local_count);
   scope_info->SetContextGlobalCount(context_global_count);
-  scope_info->SetStrongModeFreeVariableCount(strong_mode_free_variable_count);
 
   int index = kVariablePartIndex;
   // Add parameters.
   DCHECK(index == scope_info->ParameterEntriesIndex());
   for (int i = 0; i < parameter_count; ++i) {
     scope_info->set(index++, *scope->parameter(i)->name());
   }
 
   // Add stack locals' names. We are assuming that the stack locals'
   // slots are allocated in increasing order, so we can simply add
@@ skipping 48 matching lines @@
   for (int i = 0; i < context_global_count; ++i) {
     Variable* var = context_globals[i];
     // TODO(ishell): do we need this kind of info for globals here?
     uint32_t value =
         ContextLocalMode::encode(var->mode()) |
         ContextLocalInitFlag::encode(var->initialization_flag()) |
         ContextLocalMaybeAssignedFlag::encode(var->maybe_assigned());
     scope_info->set(index++, Smi::FromInt(value));
   }
 
-  DCHECK(index == scope_info->StrongModeFreeVariableNameEntriesIndex());
-  for (int i = 0; i < strong_mode_free_variable_count; ++i) {
-    scope_info->set(index++, *strong_mode_free_variables[i]->name());
-  }
-
-  DCHECK(index == scope_info->StrongModeFreeVariablePositionEntriesIndex());
-  for (int i = 0; i < strong_mode_free_variable_count; ++i) {
-    // Unfortunately, the source code positions are stored as int even though
-    // int32_t would be enough (given the maximum source code length).
-    Handle<Object> start_position = factory->NewNumberFromInt(
-        static_cast<int32_t>(strong_mode_free_variables[i]
-                                 ->strong_mode_reference_start_position()));
-    scope_info->set(index++, *start_position);
-    Handle<Object> end_position = factory->NewNumberFromInt(
-        static_cast<int32_t>(strong_mode_free_variables[i]
-                                 ->strong_mode_reference_end_position()));
-    scope_info->set(index++, *end_position);
-  }
-
   // If the receiver is allocated, add its index.
   DCHECK(index == scope_info->ReceiverEntryIndex());
   if (has_receiver) {
     int var_index = scope->receiver()->index();
     scope_info->set(index++, Smi::FromInt(var_index));
     // ?? DCHECK(receiver_info != CONTEXT || var_index ==
     // scope_info->ContextLength() - 1);
   }
 
   // If present, add the function variable name and its index.
@@ skipping 14 matching lines @@
   return scope_info;
 }
 
 
 Handle<ScopeInfo> ScopeInfo::CreateGlobalThisBinding(Isolate* isolate) {
   DCHECK(isolate->bootstrapper()->IsActive());
 
   const int stack_local_count = 0;
   const int context_local_count = 1;
   const int context_global_count = 0;
-  const int strong_mode_free_variable_count = 0;
   const bool has_simple_parameters = true;
   const VariableAllocationInfo receiver_info = CONTEXT;
   const VariableAllocationInfo function_name_info = NONE;
   const VariableMode function_variable_mode = VAR;
   const bool has_function_name = false;
   const bool has_receiver = true;
   const int parameter_count = 0;
   const int length = kVariablePartIndex + parameter_count +
                      (1 + stack_local_count) + 2 * context_local_count +
                      2 * context_global_count +
-                     3 * strong_mode_free_variable_count +
                      (has_receiver ? 1 : 0) + (has_function_name ? 2 : 0);
 
   Factory* factory = isolate->factory();
   Handle<ScopeInfo> scope_info = factory->NewScopeInfo(length);
 
   // Encode the flags.
   int flags = ScopeTypeField::encode(SCRIPT_SCOPE) |
               CallsEvalField::encode(false) |
               LanguageModeField::encode(SLOPPY) |
               DeclarationScopeField::encode(true) |
               ReceiverVariableField::encode(receiver_info) |
               FunctionVariableField::encode(function_name_info) |
               FunctionVariableMode::encode(function_variable_mode) |
               AsmModuleField::encode(false) | AsmFunctionField::encode(false) |
               HasSimpleParametersField::encode(has_simple_parameters) |
               FunctionKindField::encode(FunctionKind::kNormalFunction);
   scope_info->SetFlags(flags);
   scope_info->SetParameterCount(parameter_count);
   scope_info->SetStackLocalCount(stack_local_count);
   scope_info->SetContextLocalCount(context_local_count);
   scope_info->SetContextGlobalCount(context_global_count);
-  scope_info->SetStrongModeFreeVariableCount(strong_mode_free_variable_count);
 
   int index = kVariablePartIndex;
   const int first_slot_index = 0;
   DCHECK(index == scope_info->StackLocalFirstSlotIndex());
   scope_info->set(index++, Smi::FromInt(first_slot_index));
   DCHECK(index == scope_info->StackLocalEntriesIndex());
 
   // Here we add info for context-allocated "this".
   DCHECK(index == scope_info->ContextLocalNameEntriesIndex());
   scope_info->set(index++, *isolate->factory()->this_string());
   DCHECK(index == scope_info->ContextLocalInfoEntriesIndex());
   const uint32_t value = ContextLocalMode::encode(CONST) |
                          ContextLocalInitFlag::encode(kCreatedInitialized) |
                          ContextLocalMaybeAssignedFlag::encode(kNotAssigned);
   scope_info->set(index++, Smi::FromInt(value));
 
-  DCHECK(index == scope_info->StrongModeFreeVariableNameEntriesIndex());
-  DCHECK(index == scope_info->StrongModeFreeVariablePositionEntriesIndex());
-
   // And here we record that this scopeinfo binds a receiver.
   DCHECK(index == scope_info->ReceiverEntryIndex());
   const int receiver_index = Context::MIN_CONTEXT_SLOTS + 0;
   scope_info->set(index++, Smi::FromInt(receiver_index));
 
   DCHECK(index == scope_info->FunctionNameEntryIndex());
 
   DCHECK_EQ(index, scope_info->length());
   DCHECK_EQ(scope_info->ParameterCount(), 0);
   DCHECK_EQ(scope_info->ContextLength(), Context::MIN_CONTEXT_SLOTS + 1);
@@ skipping 183 matching lines @@
   // There's currently no flag stored on the ScopeInfo to indicate that a
   // variable is a compiler-introduced temporary. However, to avoid conflict
   // with user declarations, the current temporaries like .generator_object and
   // .result start with a dot, so we can use that as a flag. It's a hack!
   Handle<String> name(LocalName(var));
   return (name->length() > 0 && name->Get(0) == '.') ||
          name->Equals(*GetIsolate()->factory()->this_string());
 }
 
 
-String* ScopeInfo::StrongModeFreeVariableName(int var) {
-  DCHECK(0 <= var && var < StrongModeFreeVariableCount());
-  int info_index = StrongModeFreeVariableNameEntriesIndex() + var;
-  return String::cast(get(info_index));
-}
-
-
-int ScopeInfo::StrongModeFreeVariableStartPosition(int var) {
-  DCHECK(0 <= var && var < StrongModeFreeVariableCount());
-  int info_index = StrongModeFreeVariablePositionEntriesIndex() + var * 2;
-  int32_t value = 0;
-  bool ok = get(info_index)->ToInt32(&value);
-  USE(ok);
-  DCHECK(ok);
-  return value;
-}
-
-
-int ScopeInfo::StrongModeFreeVariableEndPosition(int var) {
-  DCHECK(0 <= var && var < StrongModeFreeVariableCount());
-  int info_index = StrongModeFreeVariablePositionEntriesIndex() + var * 2 + 1;
-  int32_t value = 0;
-  bool ok = get(info_index)->ToInt32(&value);
-  USE(ok);
-  DCHECK(ok);
-  return value;
-}
-
-
 int ScopeInfo::StackSlotIndex(String* name) {
   DCHECK(name->IsInternalizedString());
   if (length() > 0) {
     int first_slot_index = Smi::cast(get(StackLocalFirstSlotIndex()))->value();
     int start = StackLocalEntriesIndex();
     int end = StackLocalEntriesIndex() + StackLocalCount();
     for (int i = start; i < end; ++i) {
       if (name == get(i)) {
         return i - start + first_slot_index;
       }
@@ skipping 160 matching lines @@
 int ScopeInfo::ContextLocalInfoEntriesIndex() {
   return ContextGlobalNameEntriesIndex() + ContextGlobalCount();
 }
 
 
 int ScopeInfo::ContextGlobalInfoEntriesIndex() {
   return ContextLocalInfoEntriesIndex() + ContextLocalCount();
 }
 
 
-int ScopeInfo::StrongModeFreeVariableNameEntriesIndex() {
+int ScopeInfo::ReceiverEntryIndex() {
   return ContextGlobalInfoEntriesIndex() + ContextGlobalCount();
 }
 
 
-int ScopeInfo::StrongModeFreeVariablePositionEntriesIndex() {
-  return StrongModeFreeVariableNameEntriesIndex() +
-         StrongModeFreeVariableCount();
-}
-
-
-int ScopeInfo::ReceiverEntryIndex() {
-  return StrongModeFreeVariablePositionEntriesIndex() +
-         2 * StrongModeFreeVariableCount();
-}
-
-
 int ScopeInfo::FunctionNameEntryIndex() {
   return ReceiverEntryIndex() + (HasAllocatedReceiver() ? 1 : 0);
 }
 
 
 int ContextSlotCache::Hash(Object* data, String* name) {
   // Uses only lower 32 bits if pointers are larger.
   uintptr_t addr_hash =
       static_cast<uint32_t>(reinterpret_cast<uintptr_t>(data)) >> 2;
   return static_cast<int>((addr_hash ^ name->Hash()) % kLength);
@@ skipping 128 matching lines @@
     info->set_mode(i, var->mode());
     DCHECK(var->index() >= 0);
     info->set_index(i, var->index());
   }
   DCHECK(i == info->length());
   return info;
 }
 
 }  // namespace internal
 }  // namespace v8