1// Copyright 2011 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
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11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28#include "v8.h"
29
30#include "ast.h"
31#include "scopes.h"
32#include "variables.h"
33
34namespace v8 {
35namespace internal {
36
37// ----------------------------------------------------------------------------
38// Implementation Variable.
39
40const char* Variable::Mode2String(VariableMode mode) {
41  switch (mode) {
42    case VAR: return "VAR";
43    case CONST: return "CONST";
44    case CONST_HARMONY: return "CONST";
45    case LET: return "LET";
46    case DYNAMIC: return "DYNAMIC";
47    case DYNAMIC_GLOBAL: return "DYNAMIC_GLOBAL";
48    case DYNAMIC_LOCAL: return "DYNAMIC_LOCAL";
49    case INTERNAL: return "INTERNAL";
50    case TEMPORARY: return "TEMPORARY";
51  }
52  UNREACHABLE();
53  return NULL;
54}
55
56
57Variable::Variable(Scope* scope,
58                   Handle<String> name,
59                   VariableMode mode,
60                   bool is_valid_LHS,
61                   Kind kind,
62                   InitializationFlag initialization_flag,
63                   Interface* interface)
64  : scope_(scope),
65    name_(name),
66    mode_(mode),
67    kind_(kind),
68    location_(UNALLOCATED),
69    index_(-1),
70    initializer_position_(RelocInfo::kNoPosition),
71    local_if_not_shadowed_(NULL),
72    is_valid_LHS_(is_valid_LHS),
73    force_context_allocation_(false),
74    is_used_(false),
75    initialization_flag_(initialization_flag),
76    interface_(interface) {
77  // Names must be canonicalized for fast equality checks.
78  ASSERT(name->IsSymbol());
79  // Var declared variables never need initialization.
80  ASSERT(!(mode == VAR && initialization_flag == kNeedsInitialization));
81}
82
83
84bool Variable::is_global() const {
85  // Temporaries are never global, they must always be allocated in the
86  // activation frame.
87  return mode_ != TEMPORARY && scope_ != NULL && scope_->is_global_scope();
88}
89
90
91int Variable::CompareIndex(Variable* const* v, Variable* const* w) {
92  int x = (*v)->index();
93  int y = (*w)->index();
94  // Consider sorting them according to type as well?
95  return x - y;
96}
97
98} }  // namespace v8::internal
99