Initial import.

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diff --git a/chromium/v8/src/variables.h b/chromium/v8/src/variables.h
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+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef V8_VARIABLES_H_
+#define V8_VARIABLES_H_
+
+#include "zone.h"
+#include "interface.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 Variable: public ZoneObject {
+ public:
+  enum Kind {
+    NORMAL,
+    THIS,
+    ARGUMENTS
+  };
+
+  enum Location {
+    // Before and during variable allocation, a variable whose location is
+    // not yet determined.  After allocation, a variable looked up as a
+    // property on the global object (and possibly absent).  name() is the
+    // variable name, index() is invalid.
+    UNALLOCATED,
+
+    // A slot in the parameter section on the stack.  index() is the
+    // parameter index, counting left-to-right.  The receiver is index -1;
+    // the first parameter is index 0.
+    PARAMETER,
+
+    // A slot in the local section on the stack.  index() is the variable
+    // index in the stack frame, starting at 0.
+    LOCAL,
+
+    // An indexed slot in a heap context.  index() is the variable index in
+    // the context object on the heap, starting at 0.  scope() is the
+    // corresponding scope.
+    CONTEXT,
+
+    // A named slot in a heap context.  name() is the variable name in the
+    // context object on the heap, with lookup starting at the current
+    // context.  index() is invalid.
+    LOOKUP
+  };
+
+  Variable(Scope* scope,
+           Handle<String> name,
+           VariableMode mode,
+           bool is_valid_lhs,
+           Kind kind,
+           InitializationFlag initialization_flag,
+           Interface* interface = Interface::NewValue());
+
+  // Printing support
+  static const char* Mode2String(VariableMode mode);
+
+  bool IsValidLeftHandSide() { return is_valid_LHS_; }
+
+  // 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 global scope). scope() is NULL in that case. Currently the
+  // scope is only used to follow the context chain length.
+  Scope* scope() const { return scope_; }
+
+  Handle<String> name() const { return name_; }
+  VariableMode mode() const { return mode_; }
+  bool has_forced_context_allocation() const {
+    return force_context_allocation_;
+  }
+  void ForceContextAllocation() {
+    ASSERT(mode_ != TEMPORARY);
+    force_context_allocation_ = true;
+  }
+  bool is_used() { return is_used_; }
+  void set_is_used(bool flag) { is_used_ = flag; }
+
+  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_ == UNALLOCATED; }
+  bool IsParameter() const { return location_ == PARAMETER; }
+  bool IsStackLocal() const { return location_ == LOCAL; }
+  bool IsStackAllocated() const { return IsParameter() || IsStackLocal(); }
+  bool IsContextSlot() const { return location_ == CONTEXT; }
+  bool IsLookupSlot() const { return location_ == LOOKUP; }
+  bool IsGlobalObjectProperty() 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_this() const { return kind_ == THIS; }
+  bool is_arguments() const { return kind_ == ARGUMENTS; }
+
+  // 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 {
+    ASSERT(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;
+  }
+
+  Location location() const { return location_; }
+  int index() const { return index_; }
+  InitializationFlag initialization_flag() const {
+    return initialization_flag_;
+  }
+  Interface* interface() const { return interface_; }
+
+  void AllocateTo(Location location, int index) {
+    location_ = location;
+    index_ = index;
+  }
+
+  static int CompareIndex(Variable* const* v, Variable* const* w);
+
+ private:
+  Scope* scope_;
+  Handle<String> name_;
+  VariableMode mode_;
+  Kind kind_;
+  Location location_;
+  int index_;
+  int initializer_position_;
+
+  // If this field is set, this variable references the stored locally bound
+  // variable, but it might be shadowed by variable bindings introduced by
+  // non-strict 'eval' calls between the reference scope (inclusive) and the
+  // binding scope (exclusive).
+  Variable* local_if_not_shadowed_;
+
+  // Valid as a LHS? (const and this are not valid LHS, for example)
+  bool is_valid_LHS_;
+
+  // Usage info.
+  bool force_context_allocation_;  // set by variable resolver
+  bool is_used_;
+  InitializationFlag initialization_flag_;
+
+  // Module type info.
+  Interface* interface_;
+};
+
+
+} }  // namespace v8::internal
+
+#endif  // V8_VARIABLES_H_