Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 1 | // Copyright 2012 the V8 project authors. All rights reserved. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 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 |
| 10 | // disclaimer in the documentation and/or other materials provided |
| 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 |
| 24 | // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 25 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 26 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | |
| 28 | #ifndef V8_CONTEXTS_H_ |
| 29 | #define V8_CONTEXTS_H_ |
| 30 | |
Kristian Monsen | 80d68ea | 2010-09-08 11:05:35 +0100 | [diff] [blame] | 31 | #include "heap.h" |
| 32 | #include "objects.h" |
| 33 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 34 | namespace v8 { |
| 35 | namespace internal { |
| 36 | |
| 37 | |
| 38 | enum ContextLookupFlags { |
| 39 | FOLLOW_CONTEXT_CHAIN = 1, |
| 40 | FOLLOW_PROTOTYPE_CHAIN = 2, |
| 41 | |
| 42 | DONT_FOLLOW_CHAINS = 0, |
| 43 | FOLLOW_CHAINS = FOLLOW_CONTEXT_CHAIN | FOLLOW_PROTOTYPE_CHAIN |
| 44 | }; |
| 45 | |
| 46 | |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 47 | // ES5 10.2 defines lexical environments with mutable and immutable bindings. |
| 48 | // Immutable bindings have two states, initialized and uninitialized, and |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 49 | // their state is changed by the InitializeImmutableBinding method. The |
| 50 | // BindingFlags enum represents information if a binding has definitely been |
| 51 | // initialized. A mutable binding does not need to be checked and thus has |
| 52 | // the BindingFlag MUTABLE_IS_INITIALIZED. |
| 53 | // |
| 54 | // There are two possibilities for immutable bindings |
| 55 | // * 'const' declared variables. They are initialized when evaluating the |
| 56 | // corresponding declaration statement. They need to be checked for being |
| 57 | // initialized and thus get the flag IMMUTABLE_CHECK_INITIALIZED. |
| 58 | // * The function name of a named function literal. The binding is immediately |
| 59 | // initialized when entering the function and thus does not need to be |
| 60 | // checked. it gets the BindingFlag IMMUTABLE_IS_INITIALIZED. |
| 61 | // Accessing an uninitialized binding produces the undefined value. |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 62 | // |
| 63 | // The harmony proposal for block scoped bindings also introduces the |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 64 | // uninitialized state for mutable bindings. |
| 65 | // * A 'let' declared variable. They are initialized when evaluating the |
| 66 | // corresponding declaration statement. They need to be checked for being |
| 67 | // initialized and thus get the flag MUTABLE_CHECK_INITIALIZED. |
| 68 | // * A 'var' declared variable. It is initialized immediately upon creation |
| 69 | // and thus doesn't need to be checked. It gets the flag |
| 70 | // MUTABLE_IS_INITIALIZED. |
| 71 | // * Catch bound variables, function parameters and variables introduced by |
| 72 | // function declarations are initialized immediately and do not need to be |
| 73 | // checked. Thus they get the flag MUTABLE_IS_INITIALIZED. |
| 74 | // Immutable bindings in harmony mode get the _HARMONY flag variants. Accessing |
| 75 | // an uninitialized binding produces a reference error. |
| 76 | // |
| 77 | // In V8 uninitialized bindings are set to the hole value upon creation and set |
| 78 | // to a different value upon initialization. |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 79 | enum BindingFlags { |
| 80 | MUTABLE_IS_INITIALIZED, |
| 81 | MUTABLE_CHECK_INITIALIZED, |
| 82 | IMMUTABLE_IS_INITIALIZED, |
| 83 | IMMUTABLE_CHECK_INITIALIZED, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 84 | IMMUTABLE_IS_INITIALIZED_HARMONY, |
| 85 | IMMUTABLE_CHECK_INITIALIZED_HARMONY, |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 86 | MISSING_BINDING |
| 87 | }; |
| 88 | |
| 89 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 90 | // Heap-allocated activation contexts. |
| 91 | // |
| 92 | // Contexts are implemented as FixedArray objects; the Context |
| 93 | // class is a convenience interface casted on a FixedArray object. |
| 94 | // |
| 95 | // Note: Context must have no virtual functions and Context objects |
| 96 | // must always be allocated via Heap::AllocateContext() or |
| 97 | // Factory::NewContext. |
| 98 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 99 | #define GLOBAL_CONTEXT_FIELDS(V) \ |
| 100 | V(GLOBAL_PROXY_INDEX, JSObject, global_proxy_object) \ |
| 101 | V(SECURITY_TOKEN_INDEX, Object, security_token) \ |
| 102 | V(BOOLEAN_FUNCTION_INDEX, JSFunction, boolean_function) \ |
| 103 | V(NUMBER_FUNCTION_INDEX, JSFunction, number_function) \ |
| 104 | V(STRING_FUNCTION_INDEX, JSFunction, string_function) \ |
Iain Merrick | 7568138 | 2010-08-19 15:07:18 +0100 | [diff] [blame] | 105 | V(STRING_FUNCTION_PROTOTYPE_MAP_INDEX, Map, string_function_prototype_map) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 106 | V(OBJECT_FUNCTION_INDEX, JSFunction, object_function) \ |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 107 | V(INTERNAL_ARRAY_FUNCTION_INDEX, JSFunction, internal_array_function) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 108 | V(ARRAY_FUNCTION_INDEX, JSFunction, array_function) \ |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 109 | V(SMI_JS_ARRAY_MAP_INDEX, Object, smi_js_array_map) \ |
| 110 | V(DOUBLE_JS_ARRAY_MAP_INDEX, Object, double_js_array_map) \ |
| 111 | V(OBJECT_JS_ARRAY_MAP_INDEX, Object, object_js_array_map) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 112 | V(DATE_FUNCTION_INDEX, JSFunction, date_function) \ |
| 113 | V(JSON_OBJECT_INDEX, JSObject, json_object) \ |
| 114 | V(REGEXP_FUNCTION_INDEX, JSFunction, regexp_function) \ |
| 115 | V(INITIAL_OBJECT_PROTOTYPE_INDEX, JSObject, initial_object_prototype) \ |
| 116 | V(CREATE_DATE_FUN_INDEX, JSFunction, create_date_fun) \ |
| 117 | V(TO_NUMBER_FUN_INDEX, JSFunction, to_number_fun) \ |
| 118 | V(TO_STRING_FUN_INDEX, JSFunction, to_string_fun) \ |
| 119 | V(TO_DETAIL_STRING_FUN_INDEX, JSFunction, to_detail_string_fun) \ |
| 120 | V(TO_OBJECT_FUN_INDEX, JSFunction, to_object_fun) \ |
| 121 | V(TO_INTEGER_FUN_INDEX, JSFunction, to_integer_fun) \ |
| 122 | V(TO_UINT32_FUN_INDEX, JSFunction, to_uint32_fun) \ |
| 123 | V(TO_INT32_FUN_INDEX, JSFunction, to_int32_fun) \ |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 124 | V(GLOBAL_EVAL_FUN_INDEX, JSFunction, global_eval_fun) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 125 | V(INSTANTIATE_FUN_INDEX, JSFunction, instantiate_fun) \ |
| 126 | V(CONFIGURE_INSTANCE_FUN_INDEX, JSFunction, configure_instance_fun) \ |
| 127 | V(FUNCTION_MAP_INDEX, Map, function_map) \ |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 128 | V(STRICT_MODE_FUNCTION_MAP_INDEX, Map, strict_mode_function_map) \ |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 129 | V(FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, Map, function_without_prototype_map) \ |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 130 | V(STRICT_MODE_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, Map, \ |
| 131 | strict_mode_function_without_prototype_map) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 132 | V(FUNCTION_INSTANCE_MAP_INDEX, Map, function_instance_map) \ |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 133 | V(STRICT_MODE_FUNCTION_INSTANCE_MAP_INDEX, Map, \ |
| 134 | strict_mode_function_instance_map) \ |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 135 | V(REGEXP_RESULT_MAP_INDEX, Map, regexp_result_map)\ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 136 | V(ARGUMENTS_BOILERPLATE_INDEX, JSObject, arguments_boilerplate) \ |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 137 | V(ALIASED_ARGUMENTS_BOILERPLATE_INDEX, JSObject, \ |
| 138 | aliased_arguments_boilerplate) \ |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 139 | V(STRICT_MODE_ARGUMENTS_BOILERPLATE_INDEX, JSObject, \ |
| 140 | strict_mode_arguments_boilerplate) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 141 | V(MESSAGE_LISTENERS_INDEX, JSObject, message_listeners) \ |
| 142 | V(MAKE_MESSAGE_FUN_INDEX, JSFunction, make_message_fun) \ |
| 143 | V(GET_STACK_TRACE_LINE_INDEX, JSFunction, get_stack_trace_line_fun) \ |
| 144 | V(CONFIGURE_GLOBAL_INDEX, JSFunction, configure_global_fun) \ |
| 145 | V(FUNCTION_CACHE_INDEX, JSObject, function_cache) \ |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 146 | V(JSFUNCTION_RESULT_CACHES_INDEX, FixedArray, jsfunction_result_caches) \ |
Kristian Monsen | 80d68ea | 2010-09-08 11:05:35 +0100 | [diff] [blame] | 147 | V(NORMALIZED_MAP_CACHE_INDEX, NormalizedMapCache, normalized_map_cache) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 148 | V(RUNTIME_CONTEXT_INDEX, Context, runtime_context) \ |
| 149 | V(CALL_AS_FUNCTION_DELEGATE_INDEX, JSFunction, call_as_function_delegate) \ |
| 150 | V(CALL_AS_CONSTRUCTOR_DELEGATE_INDEX, JSFunction, \ |
| 151 | call_as_constructor_delegate) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 152 | V(SCRIPT_FUNCTION_INDEX, JSFunction, script_function) \ |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 153 | V(OPAQUE_REFERENCE_FUNCTION_INDEX, JSFunction, opaque_reference_function) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 154 | V(CONTEXT_EXTENSION_FUNCTION_INDEX, JSFunction, context_extension_function) \ |
| 155 | V(OUT_OF_MEMORY_INDEX, Object, out_of_memory) \ |
| 156 | V(MAP_CACHE_INDEX, Object, map_cache) \ |
Ben Murdoch | 257744e | 2011-11-30 15:57:28 +0000 | [diff] [blame] | 157 | V(CONTEXT_DATA_INDEX, Object, data) \ |
| 158 | V(ALLOW_CODE_GEN_FROM_STRINGS_INDEX, Object, allow_code_gen_from_strings) \ |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 159 | V(TO_COMPLETE_PROPERTY_DESCRIPTOR_INDEX, JSFunction, \ |
| 160 | to_complete_property_descriptor) \ |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 161 | V(DERIVED_HAS_TRAP_INDEX, JSFunction, derived_has_trap) \ |
| 162 | V(DERIVED_GET_TRAP_INDEX, JSFunction, derived_get_trap) \ |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 163 | V(DERIVED_SET_TRAP_INDEX, JSFunction, derived_set_trap) \ |
| 164 | V(PROXY_ENUMERATE, JSFunction, proxy_enumerate) \ |
| 165 | V(RANDOM_SEED_INDEX, ByteArray, random_seed) |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 166 | |
| 167 | // JSFunctions are pairs (context, function code), sometimes also called |
| 168 | // closures. A Context object is used to represent function contexts and |
| 169 | // dynamically pushed 'with' contexts (or 'scopes' in ECMA-262 speak). |
| 170 | // |
| 171 | // At runtime, the contexts build a stack in parallel to the execution |
| 172 | // stack, with the top-most context being the current context. All contexts |
| 173 | // have the following slots: |
| 174 | // |
| 175 | // [ closure ] This is the current function. It is the same for all |
| 176 | // contexts inside a function. It provides access to the |
| 177 | // incoming context (i.e., the outer context, which may |
| 178 | // or may not become the current function's context), and |
| 179 | // it provides access to the functions code and thus it's |
| 180 | // scope information, which in turn contains the names of |
| 181 | // statically allocated context slots. The names are needed |
| 182 | // for dynamic lookups in the presence of 'with' or 'eval'. |
| 183 | // |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 184 | // [ previous ] A pointer to the previous context. It is NULL for |
| 185 | // function contexts, and non-NULL for 'with' contexts. |
| 186 | // Used to implement the 'with' statement. |
| 187 | // |
| 188 | // [ extension ] A pointer to an extension JSObject, or NULL. Used to |
| 189 | // implement 'with' statements and dynamic declarations |
| 190 | // (through 'eval'). The object in a 'with' statement is |
| 191 | // stored in the extension slot of a 'with' context. |
| 192 | // Dynamically declared variables/functions are also added |
| 193 | // to lazily allocated extension object. Context::Lookup |
| 194 | // searches the extension object for properties. |
| 195 | // |
| 196 | // [ global ] A pointer to the global object. Provided for quick |
| 197 | // access to the global object from inside the code (since |
| 198 | // we always have a context pointer). |
| 199 | // |
| 200 | // In addition, function contexts may have statically allocated context slots |
| 201 | // to store local variables/functions that are accessed from inner functions |
| 202 | // (via static context addresses) or through 'eval' (dynamic context lookups). |
| 203 | // Finally, the global context contains additional slots for fast access to |
| 204 | // global properties. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 205 | |
| 206 | class Context: public FixedArray { |
| 207 | public: |
| 208 | // Conversions. |
| 209 | static Context* cast(Object* context) { |
| 210 | ASSERT(context->IsContext()); |
| 211 | return reinterpret_cast<Context*>(context); |
| 212 | } |
| 213 | |
| 214 | // The default context slot layout; indices are FixedArray slot indices. |
| 215 | enum { |
| 216 | // These slots are in all contexts. |
| 217 | CLOSURE_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 218 | PREVIOUS_INDEX, |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 219 | // The extension slot is used for either the global object (in global |
| 220 | // contexts), eval extension object (function contexts), subject of with |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 221 | // (with contexts), or the variable name (catch contexts), the serialized |
| 222 | // scope info (block contexts). |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 223 | EXTENSION_INDEX, |
| 224 | GLOBAL_INDEX, |
| 225 | MIN_CONTEXT_SLOTS, |
| 226 | |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 227 | // This slot holds the thrown value in catch contexts. |
| 228 | THROWN_OBJECT_INDEX = MIN_CONTEXT_SLOTS, |
| 229 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 230 | // These slots are only in global contexts. |
| 231 | GLOBAL_PROXY_INDEX = MIN_CONTEXT_SLOTS, |
| 232 | SECURITY_TOKEN_INDEX, |
| 233 | ARGUMENTS_BOILERPLATE_INDEX, |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 234 | ALIASED_ARGUMENTS_BOILERPLATE_INDEX, |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 235 | STRICT_MODE_ARGUMENTS_BOILERPLATE_INDEX, |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 236 | REGEXP_RESULT_MAP_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 237 | FUNCTION_MAP_INDEX, |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 238 | STRICT_MODE_FUNCTION_MAP_INDEX, |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 239 | FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 240 | STRICT_MODE_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 241 | FUNCTION_INSTANCE_MAP_INDEX, |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 242 | STRICT_MODE_FUNCTION_INSTANCE_MAP_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 243 | INITIAL_OBJECT_PROTOTYPE_INDEX, |
| 244 | BOOLEAN_FUNCTION_INDEX, |
| 245 | NUMBER_FUNCTION_INDEX, |
| 246 | STRING_FUNCTION_INDEX, |
Iain Merrick | 7568138 | 2010-08-19 15:07:18 +0100 | [diff] [blame] | 247 | STRING_FUNCTION_PROTOTYPE_MAP_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 248 | OBJECT_FUNCTION_INDEX, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 249 | INTERNAL_ARRAY_FUNCTION_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 250 | ARRAY_FUNCTION_INDEX, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 251 | SMI_JS_ARRAY_MAP_INDEX, |
| 252 | DOUBLE_JS_ARRAY_MAP_INDEX, |
| 253 | OBJECT_JS_ARRAY_MAP_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 254 | DATE_FUNCTION_INDEX, |
| 255 | JSON_OBJECT_INDEX, |
| 256 | REGEXP_FUNCTION_INDEX, |
| 257 | CREATE_DATE_FUN_INDEX, |
| 258 | TO_NUMBER_FUN_INDEX, |
| 259 | TO_STRING_FUN_INDEX, |
| 260 | TO_DETAIL_STRING_FUN_INDEX, |
| 261 | TO_OBJECT_FUN_INDEX, |
| 262 | TO_INTEGER_FUN_INDEX, |
| 263 | TO_UINT32_FUN_INDEX, |
| 264 | TO_INT32_FUN_INDEX, |
| 265 | TO_BOOLEAN_FUN_INDEX, |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 266 | GLOBAL_EVAL_FUN_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 267 | INSTANTIATE_FUN_INDEX, |
| 268 | CONFIGURE_INSTANCE_FUN_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 269 | MESSAGE_LISTENERS_INDEX, |
| 270 | MAKE_MESSAGE_FUN_INDEX, |
| 271 | GET_STACK_TRACE_LINE_INDEX, |
| 272 | CONFIGURE_GLOBAL_INDEX, |
| 273 | FUNCTION_CACHE_INDEX, |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 274 | JSFUNCTION_RESULT_CACHES_INDEX, |
Kristian Monsen | 80d68ea | 2010-09-08 11:05:35 +0100 | [diff] [blame] | 275 | NORMALIZED_MAP_CACHE_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 276 | RUNTIME_CONTEXT_INDEX, |
| 277 | CALL_AS_FUNCTION_DELEGATE_INDEX, |
| 278 | CALL_AS_CONSTRUCTOR_DELEGATE_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 279 | SCRIPT_FUNCTION_INDEX, |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 280 | OPAQUE_REFERENCE_FUNCTION_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 281 | CONTEXT_EXTENSION_FUNCTION_INDEX, |
| 282 | OUT_OF_MEMORY_INDEX, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 283 | CONTEXT_DATA_INDEX, |
Ben Murdoch | 257744e | 2011-11-30 15:57:28 +0000 | [diff] [blame] | 284 | ALLOW_CODE_GEN_FROM_STRINGS_INDEX, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 285 | TO_COMPLETE_PROPERTY_DESCRIPTOR_INDEX, |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 286 | DERIVED_HAS_TRAP_INDEX, |
Ben Murdoch | 257744e | 2011-11-30 15:57:28 +0000 | [diff] [blame] | 287 | DERIVED_GET_TRAP_INDEX, |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 288 | DERIVED_SET_TRAP_INDEX, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 289 | PROXY_ENUMERATE, |
| 290 | RANDOM_SEED_INDEX, |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 291 | |
| 292 | // Properties from here are treated as weak references by the full GC. |
| 293 | // Scavenge treats them as strong references. |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 294 | OPTIMIZED_FUNCTIONS_LIST, // Weak. |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 295 | MAP_CACHE_INDEX, // Weak. |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 296 | NEXT_CONTEXT_LINK, // Weak. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 297 | |
| 298 | // Total number of slots. |
| 299 | GLOBAL_CONTEXT_SLOTS, |
| 300 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 301 | FIRST_WEAK_SLOT = OPTIMIZED_FUNCTIONS_LIST |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 302 | }; |
| 303 | |
| 304 | // Direct slot access. |
| 305 | JSFunction* closure() { return JSFunction::cast(get(CLOSURE_INDEX)); } |
| 306 | void set_closure(JSFunction* closure) { set(CLOSURE_INDEX, closure); } |
| 307 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 308 | Context* previous() { |
| 309 | Object* result = unchecked_previous(); |
| 310 | ASSERT(IsBootstrappingOrContext(result)); |
| 311 | return reinterpret_cast<Context*>(result); |
| 312 | } |
| 313 | void set_previous(Context* context) { set(PREVIOUS_INDEX, context); } |
| 314 | |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 315 | bool has_extension() { return extension() != NULL; } |
| 316 | Object* extension() { return get(EXTENSION_INDEX); } |
| 317 | void set_extension(Object* object) { set(EXTENSION_INDEX, object); } |
| 318 | |
| 319 | // Get the context where var declarations will be hoisted to, which |
| 320 | // may be the context itself. |
| 321 | Context* declaration_context(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 322 | |
| 323 | GlobalObject* global() { |
| 324 | Object* result = get(GLOBAL_INDEX); |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 325 | ASSERT(IsBootstrappingOrGlobalObject(result)); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 326 | return reinterpret_cast<GlobalObject*>(result); |
| 327 | } |
| 328 | void set_global(GlobalObject* global) { set(GLOBAL_INDEX, global); } |
| 329 | |
| 330 | // Returns a JSGlobalProxy object or null. |
| 331 | JSObject* global_proxy(); |
| 332 | void set_global_proxy(JSObject* global); |
| 333 | |
| 334 | // The builtins object. |
| 335 | JSBuiltinsObject* builtins(); |
| 336 | |
| 337 | // Compute the global context by traversing the context chain. |
| 338 | Context* global_context(); |
| 339 | |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 340 | // Predicates for context types. IsGlobalContext is defined on Object |
| 341 | // because we frequently have to know if arbitrary objects are global |
| 342 | // contexts. |
| 343 | bool IsFunctionContext() { |
| 344 | Map* map = this->map(); |
| 345 | return map == map->GetHeap()->function_context_map(); |
| 346 | } |
| 347 | bool IsCatchContext() { |
| 348 | Map* map = this->map(); |
| 349 | return map == map->GetHeap()->catch_context_map(); |
| 350 | } |
| 351 | bool IsWithContext() { |
| 352 | Map* map = this->map(); |
| 353 | return map == map->GetHeap()->with_context_map(); |
| 354 | } |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 355 | bool IsBlockContext() { |
| 356 | Map* map = this->map(); |
| 357 | return map == map->GetHeap()->block_context_map(); |
| 358 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 359 | bool IsModuleContext() { |
| 360 | Map* map = this->map(); |
| 361 | return map == map->GetHeap()->module_context_map(); |
| 362 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 363 | |
| 364 | // Tells whether the global context is marked with out of memory. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 365 | inline bool has_out_of_memory(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 366 | |
| 367 | // Mark the global context with out of memory. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 368 | inline void mark_out_of_memory(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 369 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 370 | // A global context hold a list of all functions which have been optimized. |
| 371 | void AddOptimizedFunction(JSFunction* function); |
| 372 | void RemoveOptimizedFunction(JSFunction* function); |
| 373 | Object* OptimizedFunctionsListHead(); |
| 374 | void ClearOptimizedFunctions(); |
| 375 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 376 | static int GetContextMapIndexFromElementsKind( |
| 377 | ElementsKind elements_kind) { |
| 378 | if (elements_kind == FAST_DOUBLE_ELEMENTS) { |
| 379 | return Context::DOUBLE_JS_ARRAY_MAP_INDEX; |
| 380 | } else if (elements_kind == FAST_ELEMENTS) { |
| 381 | return Context::OBJECT_JS_ARRAY_MAP_INDEX; |
| 382 | } else { |
| 383 | ASSERT(elements_kind == FAST_SMI_ONLY_ELEMENTS); |
| 384 | return Context::SMI_JS_ARRAY_MAP_INDEX; |
| 385 | } |
| 386 | } |
| 387 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 388 | #define GLOBAL_CONTEXT_FIELD_ACCESSORS(index, type, name) \ |
| 389 | void set_##name(type* value) { \ |
| 390 | ASSERT(IsGlobalContext()); \ |
| 391 | set(index, value); \ |
| 392 | } \ |
| 393 | type* name() { \ |
| 394 | ASSERT(IsGlobalContext()); \ |
| 395 | return type::cast(get(index)); \ |
| 396 | } |
| 397 | GLOBAL_CONTEXT_FIELDS(GLOBAL_CONTEXT_FIELD_ACCESSORS) |
| 398 | #undef GLOBAL_CONTEXT_FIELD_ACCESSORS |
| 399 | |
| 400 | // Lookup the the slot called name, starting with the current context. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 401 | // There are three possibilities: |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 402 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 403 | // 1) result->IsContext(): |
| 404 | // The binding was found in a context. *index is always the |
| 405 | // non-negative slot index. *attributes is NONE for var and let |
| 406 | // declarations, READ_ONLY for const declarations (never ABSENT). |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 407 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 408 | // 2) result->IsJSObject(): |
| 409 | // The binding was found as a named property in a context extension |
| 410 | // object (i.e., was introduced via eval), as a property on the subject |
| 411 | // of with, or as a property of the global object. *index is -1 and |
| 412 | // *attributes is not ABSENT. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 413 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 414 | // 3) result.is_null(): |
| 415 | // There was no binding found, *index is always -1 and *attributes is |
| 416 | // always ABSENT. |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 417 | Handle<Object> Lookup(Handle<String> name, |
| 418 | ContextLookupFlags flags, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame^] | 419 | int* index, |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 420 | PropertyAttributes* attributes, |
| 421 | BindingFlags* binding_flags); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 422 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 423 | // Code generation support. |
| 424 | static int SlotOffset(int index) { |
| 425 | return kHeaderSize + index * kPointerSize - kHeapObjectTag; |
| 426 | } |
| 427 | |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 428 | static const int kSize = kHeaderSize + GLOBAL_CONTEXT_SLOTS * kPointerSize; |
| 429 | |
| 430 | // GC support. |
| 431 | typedef FixedBodyDescriptor< |
| 432 | kHeaderSize, kSize, kSize> ScavengeBodyDescriptor; |
| 433 | |
| 434 | typedef FixedBodyDescriptor< |
| 435 | kHeaderSize, |
| 436 | kHeaderSize + FIRST_WEAK_SLOT * kPointerSize, |
| 437 | kSize> MarkCompactBodyDescriptor; |
| 438 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 439 | private: |
| 440 | // Unchecked access to the slots. |
| 441 | Object* unchecked_previous() { return get(PREVIOUS_INDEX); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 442 | |
| 443 | #ifdef DEBUG |
| 444 | // Bootstrapping-aware type checks. |
| 445 | static bool IsBootstrappingOrContext(Object* object); |
| 446 | static bool IsBootstrappingOrGlobalObject(Object* object); |
| 447 | #endif |
| 448 | }; |
| 449 | |
| 450 | } } // namespace v8::internal |
| 451 | |
| 452 | #endif // V8_CONTEXTS_H_ |