Upgrade V8 to version 4.9.385.28

https://chromium.googlesource.com/v8/v8/+/4.9.385.28

FPIIM-449

Change-Id: I4b2e74289d4bf3667f2f3dc8aa2e541f63e26eb4
diff --git a/src/ast/variables.h b/src/ast/variables.h
new file mode 100644
index 0000000..ca5d1cd
--- /dev/null
+++ b/src/ast/variables.h
@@ -0,0 +1,218 @@
+// 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.
+
+#ifndef V8_AST_VARIABLES_H_
+#define V8_AST_VARIABLES_H_
+
+#include "src/ast/ast-value-factory.h"
+#include "src/zone.h"
+
+namespace v8 {
+namespace internal {
+
+// The AST refers to variables via VariableProxies - placeholders for the actual
+// variables. Variables themselves are never directly referred to from the AST,
+// they are maintained by scopes, and referred to from VariableProxies and Slots
+// after binding and variable allocation.
+
+class ClassVariable;
+
+class Variable: public ZoneObject {
+ public:
+  enum Kind { NORMAL, FUNCTION, CLASS, THIS, ARGUMENTS };
+
+  Variable(Scope* scope, const AstRawString* name, VariableMode mode, Kind kind,
+           InitializationFlag initialization_flag,
+           MaybeAssignedFlag maybe_assigned_flag = kNotAssigned);
+
+  virtual ~Variable() {}
+
+  // Printing support
+  static const char* Mode2String(VariableMode mode);
+
+  // The source code for an eval() call may refer to a variable that is
+  // in an outer scope about which we don't know anything (it may not
+  // be the script scope). scope() is NULL in that case. Currently the
+  // scope is only used to follow the context chain length.
+  Scope* scope() const { return scope_; }
+
+  // This is for adjusting the scope of temporaries used when desugaring
+  // parameter initializers.
+  void set_scope(Scope* scope) { scope_ = scope; }
+
+  Handle<String> name() const { return name_->string(); }
+  const AstRawString* raw_name() const { return name_; }
+  VariableMode mode() const { return mode_; }
+  bool has_forced_context_allocation() const {
+    return force_context_allocation_;
+  }
+  void ForceContextAllocation() {
+    force_context_allocation_ = true;
+  }
+  bool is_used() { return is_used_; }
+  void set_is_used() { is_used_ = true; }
+  MaybeAssignedFlag maybe_assigned() const { return maybe_assigned_; }
+  void set_maybe_assigned() { maybe_assigned_ = kMaybeAssigned; }
+
+  int initializer_position() { return initializer_position_; }
+  void set_initializer_position(int pos) { initializer_position_ = pos; }
+
+  bool IsVariable(Handle<String> n) const {
+    return !is_this() && name().is_identical_to(n);
+  }
+
+  bool IsUnallocated() const {
+    return location_ == VariableLocation::UNALLOCATED;
+  }
+  bool IsParameter() const { return location_ == VariableLocation::PARAMETER; }
+  bool IsStackLocal() const { return location_ == VariableLocation::LOCAL; }
+  bool IsStackAllocated() const { return IsParameter() || IsStackLocal(); }
+  bool IsContextSlot() const { return location_ == VariableLocation::CONTEXT; }
+  bool IsGlobalSlot() const { return location_ == VariableLocation::GLOBAL; }
+  bool IsUnallocatedOrGlobalSlot() const {
+    return IsUnallocated() || IsGlobalSlot();
+  }
+  bool IsLookupSlot() const { return location_ == VariableLocation::LOOKUP; }
+  bool IsGlobalObjectProperty() const;
+  bool IsStaticGlobalObjectProperty() const;
+
+  bool is_dynamic() const { return IsDynamicVariableMode(mode_); }
+  bool is_const_mode() const { return IsImmutableVariableMode(mode_); }
+  bool binding_needs_init() const {
+    return initialization_flag_ == kNeedsInitialization;
+  }
+
+  bool is_function() const { return kind_ == FUNCTION; }
+  bool is_class() const { return kind_ == CLASS; }
+  bool is_this() const { return kind_ == THIS; }
+  bool is_arguments() const { return kind_ == ARGUMENTS; }
+
+  // For script scopes, the "this" binding is provided by a ScriptContext added
+  // to the global's ScriptContextTable.  This binding might not statically
+  // resolve to a Variable::THIS binding, instead being DYNAMIC_LOCAL.  However
+  // any variable named "this" does indeed refer to a Variable::THIS binding;
+  // the grammar ensures this to be the case.  So wherever a "this" binding
+  // might be provided by the global, use HasThisName instead of is_this().
+  bool HasThisName(Isolate* isolate) const {
+    return is_this() || *name() == *isolate->factory()->this_string();
+  }
+
+  ClassVariable* AsClassVariable() {
+    DCHECK(is_class());
+    return reinterpret_cast<ClassVariable*>(this);
+  }
+
+  // True if the variable is named eval and not known to be shadowed.
+  bool is_possibly_eval(Isolate* isolate) const {
+    return IsVariable(isolate->factory()->eval_string());
+  }
+
+  Variable* local_if_not_shadowed() const {
+    DCHECK(mode_ == DYNAMIC_LOCAL && local_if_not_shadowed_ != NULL);
+    return local_if_not_shadowed_;
+  }
+
+  void set_local_if_not_shadowed(Variable* local) {
+    local_if_not_shadowed_ = local;
+  }
+
+  VariableLocation location() const { return location_; }
+  int index() const { return index_; }
+  InitializationFlag initialization_flag() const {
+    return initialization_flag_;
+  }
+
+  void AllocateTo(VariableLocation location, int index) {
+    location_ = location;
+    index_ = index;
+  }
+
+  void SetFromEval() { is_from_eval_ = true; }
+
+  static int CompareIndex(Variable* const* v, Variable* const* w);
+
+  void RecordStrongModeReference(int start_position, int end_position) {
+    // Record the earliest reference to the variable. Used in error messages for
+    // strong mode references to undeclared variables.
+    if (has_strong_mode_reference_ &&
+        strong_mode_reference_start_position_ < start_position)
+      return;
+    has_strong_mode_reference_ = true;
+    strong_mode_reference_start_position_ = start_position;
+    strong_mode_reference_end_position_ = end_position;
+  }
+
+  bool has_strong_mode_reference() const { return has_strong_mode_reference_; }
+  int strong_mode_reference_start_position() const {
+    return strong_mode_reference_start_position_;
+  }
+  int strong_mode_reference_end_position() const {
+    return strong_mode_reference_end_position_;
+  }
+  PropertyAttributes DeclarationPropertyAttributes() const {
+    int property_attributes = NONE;
+    if (IsImmutableVariableMode(mode_)) {
+      property_attributes |= READ_ONLY;
+    }
+    if (is_from_eval_) {
+      property_attributes |= EVAL_DECLARED;
+    }
+    return static_cast<PropertyAttributes>(property_attributes);
+  }
+
+ private:
+  Scope* scope_;
+  const AstRawString* name_;
+  VariableMode mode_;
+  Kind kind_;
+  VariableLocation location_;
+  int index_;
+  int initializer_position_;
+  // Tracks whether the variable is bound to a VariableProxy which is in strong
+  // mode, and if yes, the source location of the reference.
+  bool has_strong_mode_reference_;
+  int strong_mode_reference_start_position_;
+  int strong_mode_reference_end_position_;
+
+  // If this field is set, this variable references the stored locally bound
+  // variable, but it might be shadowed by variable bindings introduced by
+  // sloppy 'eval' calls between the reference scope (inclusive) and the
+  // binding scope (exclusive).
+  Variable* local_if_not_shadowed_;
+
+  // True if this variable is introduced by a sloppy eval
+  bool is_from_eval_;
+
+  // Usage info.
+  bool force_context_allocation_;  // set by variable resolver
+  bool is_used_;
+  InitializationFlag initialization_flag_;
+  MaybeAssignedFlag maybe_assigned_;
+};
+
+class ClassVariable : public Variable {
+ public:
+  ClassVariable(Scope* scope, const AstRawString* name, VariableMode mode,
+                InitializationFlag initialization_flag,
+                MaybeAssignedFlag maybe_assigned_flag = kNotAssigned,
+                int declaration_group_start = -1)
+      : Variable(scope, name, mode, Variable::CLASS, initialization_flag,
+                 maybe_assigned_flag),
+        declaration_group_start_(declaration_group_start) {}
+
+  int declaration_group_start() const { return declaration_group_start_; }
+  void set_declaration_group_start(int declaration_group_start) {
+    declaration_group_start_ = declaration_group_start;
+  }
+
+ private:
+  // For classes we keep track of consecutive groups of delcarations. They are
+  // needed for strong mode scoping checks. TODO(marja, rossberg): Implement
+  // checks for functions too.
+  int declaration_group_start_;
+};
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_AST_VARIABLES_H_