Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame^] | 1 | // Copyright 2011 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/ast/scopeinfo.h" |
| 6 | |
| 7 | #include <stdlib.h> |
| 8 | |
| 9 | #include "src/ast/scopes.h" |
| 10 | #include "src/bootstrapper.h" |
| 11 | |
| 12 | namespace v8 { |
| 13 | namespace internal { |
| 14 | |
| 15 | |
| 16 | Handle<ScopeInfo> ScopeInfo::Create(Isolate* isolate, Zone* zone, |
| 17 | Scope* scope) { |
| 18 | // Collect stack and context locals. |
| 19 | ZoneList<Variable*> stack_locals(scope->StackLocalCount(), zone); |
| 20 | ZoneList<Variable*> context_locals(scope->ContextLocalCount(), zone); |
| 21 | ZoneList<Variable*> context_globals(scope->ContextGlobalCount(), zone); |
| 22 | ZoneList<Variable*> strong_mode_free_variables(0, zone); |
| 23 | |
| 24 | scope->CollectStackAndContextLocals(&stack_locals, &context_locals, |
| 25 | &context_globals, |
| 26 | &strong_mode_free_variables); |
| 27 | const int stack_local_count = stack_locals.length(); |
| 28 | const int context_local_count = context_locals.length(); |
| 29 | const int context_global_count = context_globals.length(); |
| 30 | const int strong_mode_free_variable_count = |
| 31 | strong_mode_free_variables.length(); |
| 32 | // Make sure we allocate the correct amount. |
| 33 | DCHECK_EQ(scope->ContextLocalCount(), context_local_count); |
| 34 | DCHECK_EQ(scope->ContextGlobalCount(), context_global_count); |
| 35 | |
| 36 | // Determine use and location of the "this" binding if it is present. |
| 37 | VariableAllocationInfo receiver_info; |
| 38 | if (scope->has_this_declaration()) { |
| 39 | Variable* var = scope->receiver(); |
| 40 | if (!var->is_used()) { |
| 41 | receiver_info = UNUSED; |
| 42 | } else if (var->IsContextSlot()) { |
| 43 | receiver_info = CONTEXT; |
| 44 | } else { |
| 45 | DCHECK(var->IsParameter()); |
| 46 | receiver_info = STACK; |
| 47 | } |
| 48 | } else { |
| 49 | receiver_info = NONE; |
| 50 | } |
| 51 | |
| 52 | bool has_new_target = scope->new_target_var() != nullptr; |
| 53 | |
| 54 | // Determine use and location of the function variable if it is present. |
| 55 | VariableAllocationInfo function_name_info; |
| 56 | VariableMode function_variable_mode; |
| 57 | if (scope->is_function_scope() && scope->function() != NULL) { |
| 58 | Variable* var = scope->function()->proxy()->var(); |
| 59 | if (!var->is_used()) { |
| 60 | function_name_info = UNUSED; |
| 61 | } else if (var->IsContextSlot()) { |
| 62 | function_name_info = CONTEXT; |
| 63 | } else { |
| 64 | DCHECK(var->IsStackLocal()); |
| 65 | function_name_info = STACK; |
| 66 | } |
| 67 | function_variable_mode = var->mode(); |
| 68 | } else { |
| 69 | function_name_info = NONE; |
| 70 | function_variable_mode = VAR; |
| 71 | } |
| 72 | DCHECK(context_global_count == 0 || scope->scope_type() == SCRIPT_SCOPE); |
| 73 | |
| 74 | const bool has_function_name = function_name_info != NONE; |
| 75 | const bool has_receiver = receiver_info == STACK || receiver_info == CONTEXT; |
| 76 | const int parameter_count = scope->num_parameters(); |
| 77 | const int length = kVariablePartIndex + parameter_count + |
| 78 | (1 + stack_local_count) + 2 * context_local_count + |
| 79 | 2 * context_global_count + |
| 80 | 3 * strong_mode_free_variable_count + |
| 81 | (has_receiver ? 1 : 0) + (has_function_name ? 2 : 0); |
| 82 | |
| 83 | Factory* factory = isolate->factory(); |
| 84 | Handle<ScopeInfo> scope_info = factory->NewScopeInfo(length); |
| 85 | |
| 86 | bool has_simple_parameters = |
| 87 | scope->is_function_scope() && scope->has_simple_parameters(); |
| 88 | |
| 89 | // Encode the flags. |
| 90 | int flags = ScopeTypeField::encode(scope->scope_type()) | |
| 91 | CallsEvalField::encode(scope->calls_eval()) | |
| 92 | LanguageModeField::encode(scope->language_mode()) | |
| 93 | DeclarationScopeField::encode(scope->is_declaration_scope()) | |
| 94 | ReceiverVariableField::encode(receiver_info) | |
| 95 | HasNewTargetField::encode(has_new_target) | |
| 96 | FunctionVariableField::encode(function_name_info) | |
| 97 | FunctionVariableMode::encode(function_variable_mode) | |
| 98 | AsmModuleField::encode(scope->asm_module()) | |
| 99 | AsmFunctionField::encode(scope->asm_function()) | |
| 100 | HasSimpleParametersField::encode(has_simple_parameters) | |
| 101 | FunctionKindField::encode(scope->function_kind()); |
| 102 | scope_info->SetFlags(flags); |
| 103 | scope_info->SetParameterCount(parameter_count); |
| 104 | scope_info->SetStackLocalCount(stack_local_count); |
| 105 | scope_info->SetContextLocalCount(context_local_count); |
| 106 | scope_info->SetContextGlobalCount(context_global_count); |
| 107 | scope_info->SetStrongModeFreeVariableCount(strong_mode_free_variable_count); |
| 108 | |
| 109 | int index = kVariablePartIndex; |
| 110 | // Add parameters. |
| 111 | DCHECK(index == scope_info->ParameterEntriesIndex()); |
| 112 | for (int i = 0; i < parameter_count; ++i) { |
| 113 | scope_info->set(index++, *scope->parameter(i)->name()); |
| 114 | } |
| 115 | |
| 116 | // Add stack locals' names. We are assuming that the stack locals' |
| 117 | // slots are allocated in increasing order, so we can simply add |
| 118 | // them to the ScopeInfo object. |
| 119 | int first_slot_index; |
| 120 | if (stack_local_count > 0) { |
| 121 | first_slot_index = stack_locals[0]->index(); |
| 122 | } else { |
| 123 | first_slot_index = 0; |
| 124 | } |
| 125 | DCHECK(index == scope_info->StackLocalFirstSlotIndex()); |
| 126 | scope_info->set(index++, Smi::FromInt(first_slot_index)); |
| 127 | DCHECK(index == scope_info->StackLocalEntriesIndex()); |
| 128 | for (int i = 0; i < stack_local_count; ++i) { |
| 129 | DCHECK(stack_locals[i]->index() == first_slot_index + i); |
| 130 | scope_info->set(index++, *stack_locals[i]->name()); |
| 131 | } |
| 132 | |
| 133 | // Due to usage analysis, context-allocated locals are not necessarily in |
| 134 | // increasing order: Some of them may be parameters which are allocated before |
| 135 | // the non-parameter locals. When the non-parameter locals are sorted |
| 136 | // according to usage, the allocated slot indices may not be in increasing |
| 137 | // order with the variable list anymore. Thus, we first need to sort them by |
| 138 | // context slot index before adding them to the ScopeInfo object. |
| 139 | context_locals.Sort(&Variable::CompareIndex); |
| 140 | |
| 141 | // Add context locals' names. |
| 142 | DCHECK(index == scope_info->ContextLocalNameEntriesIndex()); |
| 143 | for (int i = 0; i < context_local_count; ++i) { |
| 144 | scope_info->set(index++, *context_locals[i]->name()); |
| 145 | } |
| 146 | |
| 147 | // Add context globals' names. |
| 148 | DCHECK(index == scope_info->ContextGlobalNameEntriesIndex()); |
| 149 | for (int i = 0; i < context_global_count; ++i) { |
| 150 | scope_info->set(index++, *context_globals[i]->name()); |
| 151 | } |
| 152 | |
| 153 | // Add context locals' info. |
| 154 | DCHECK(index == scope_info->ContextLocalInfoEntriesIndex()); |
| 155 | for (int i = 0; i < context_local_count; ++i) { |
| 156 | Variable* var = context_locals[i]; |
| 157 | uint32_t value = |
| 158 | ContextLocalMode::encode(var->mode()) | |
| 159 | ContextLocalInitFlag::encode(var->initialization_flag()) | |
| 160 | ContextLocalMaybeAssignedFlag::encode(var->maybe_assigned()); |
| 161 | scope_info->set(index++, Smi::FromInt(value)); |
| 162 | } |
| 163 | |
| 164 | // Add context globals' info. |
| 165 | DCHECK(index == scope_info->ContextGlobalInfoEntriesIndex()); |
| 166 | for (int i = 0; i < context_global_count; ++i) { |
| 167 | Variable* var = context_globals[i]; |
| 168 | // TODO(ishell): do we need this kind of info for globals here? |
| 169 | uint32_t value = |
| 170 | ContextLocalMode::encode(var->mode()) | |
| 171 | ContextLocalInitFlag::encode(var->initialization_flag()) | |
| 172 | ContextLocalMaybeAssignedFlag::encode(var->maybe_assigned()); |
| 173 | scope_info->set(index++, Smi::FromInt(value)); |
| 174 | } |
| 175 | |
| 176 | DCHECK(index == scope_info->StrongModeFreeVariableNameEntriesIndex()); |
| 177 | for (int i = 0; i < strong_mode_free_variable_count; ++i) { |
| 178 | scope_info->set(index++, *strong_mode_free_variables[i]->name()); |
| 179 | } |
| 180 | |
| 181 | DCHECK(index == scope_info->StrongModeFreeVariablePositionEntriesIndex()); |
| 182 | for (int i = 0; i < strong_mode_free_variable_count; ++i) { |
| 183 | // Unfortunately, the source code positions are stored as int even though |
| 184 | // int32_t would be enough (given the maximum source code length). |
| 185 | Handle<Object> start_position = factory->NewNumberFromInt( |
| 186 | static_cast<int32_t>(strong_mode_free_variables[i] |
| 187 | ->strong_mode_reference_start_position())); |
| 188 | scope_info->set(index++, *start_position); |
| 189 | Handle<Object> end_position = factory->NewNumberFromInt( |
| 190 | static_cast<int32_t>(strong_mode_free_variables[i] |
| 191 | ->strong_mode_reference_end_position())); |
| 192 | scope_info->set(index++, *end_position); |
| 193 | } |
| 194 | |
| 195 | // If the receiver is allocated, add its index. |
| 196 | DCHECK(index == scope_info->ReceiverEntryIndex()); |
| 197 | if (has_receiver) { |
| 198 | int var_index = scope->receiver()->index(); |
| 199 | scope_info->set(index++, Smi::FromInt(var_index)); |
| 200 | // ?? DCHECK(receiver_info != CONTEXT || var_index == |
| 201 | // scope_info->ContextLength() - 1); |
| 202 | } |
| 203 | |
| 204 | // If present, add the function variable name and its index. |
| 205 | DCHECK(index == scope_info->FunctionNameEntryIndex()); |
| 206 | if (has_function_name) { |
| 207 | int var_index = scope->function()->proxy()->var()->index(); |
| 208 | scope_info->set(index++, *scope->function()->proxy()->name()); |
| 209 | scope_info->set(index++, Smi::FromInt(var_index)); |
| 210 | DCHECK(function_name_info != CONTEXT || |
| 211 | var_index == scope_info->ContextLength() - 1); |
| 212 | } |
| 213 | |
| 214 | DCHECK(index == scope_info->length()); |
| 215 | DCHECK(scope->num_parameters() == scope_info->ParameterCount()); |
| 216 | DCHECK(scope->num_heap_slots() == scope_info->ContextLength() || |
| 217 | (scope->num_heap_slots() == kVariablePartIndex && |
| 218 | scope_info->ContextLength() == 0)); |
| 219 | return scope_info; |
| 220 | } |
| 221 | |
| 222 | |
| 223 | Handle<ScopeInfo> ScopeInfo::CreateGlobalThisBinding(Isolate* isolate) { |
| 224 | DCHECK(isolate->bootstrapper()->IsActive()); |
| 225 | |
| 226 | const int stack_local_count = 0; |
| 227 | const int context_local_count = 1; |
| 228 | const int context_global_count = 0; |
| 229 | const int strong_mode_free_variable_count = 0; |
| 230 | const bool has_simple_parameters = true; |
| 231 | const VariableAllocationInfo receiver_info = CONTEXT; |
| 232 | const VariableAllocationInfo function_name_info = NONE; |
| 233 | const VariableMode function_variable_mode = VAR; |
| 234 | const bool has_function_name = false; |
| 235 | const bool has_receiver = true; |
| 236 | const int parameter_count = 0; |
| 237 | const int length = kVariablePartIndex + parameter_count + |
| 238 | (1 + stack_local_count) + 2 * context_local_count + |
| 239 | 2 * context_global_count + |
| 240 | 3 * strong_mode_free_variable_count + |
| 241 | (has_receiver ? 1 : 0) + (has_function_name ? 2 : 0); |
| 242 | |
| 243 | Factory* factory = isolate->factory(); |
| 244 | Handle<ScopeInfo> scope_info = factory->NewScopeInfo(length); |
| 245 | |
| 246 | // Encode the flags. |
| 247 | int flags = ScopeTypeField::encode(SCRIPT_SCOPE) | |
| 248 | CallsEvalField::encode(false) | |
| 249 | LanguageModeField::encode(SLOPPY) | |
| 250 | DeclarationScopeField::encode(true) | |
| 251 | ReceiverVariableField::encode(receiver_info) | |
| 252 | FunctionVariableField::encode(function_name_info) | |
| 253 | FunctionVariableMode::encode(function_variable_mode) | |
| 254 | AsmModuleField::encode(false) | AsmFunctionField::encode(false) | |
| 255 | HasSimpleParametersField::encode(has_simple_parameters) | |
| 256 | FunctionKindField::encode(FunctionKind::kNormalFunction); |
| 257 | scope_info->SetFlags(flags); |
| 258 | scope_info->SetParameterCount(parameter_count); |
| 259 | scope_info->SetStackLocalCount(stack_local_count); |
| 260 | scope_info->SetContextLocalCount(context_local_count); |
| 261 | scope_info->SetContextGlobalCount(context_global_count); |
| 262 | scope_info->SetStrongModeFreeVariableCount(strong_mode_free_variable_count); |
| 263 | |
| 264 | int index = kVariablePartIndex; |
| 265 | const int first_slot_index = 0; |
| 266 | DCHECK(index == scope_info->StackLocalFirstSlotIndex()); |
| 267 | scope_info->set(index++, Smi::FromInt(first_slot_index)); |
| 268 | DCHECK(index == scope_info->StackLocalEntriesIndex()); |
| 269 | |
| 270 | // Here we add info for context-allocated "this". |
| 271 | DCHECK(index == scope_info->ContextLocalNameEntriesIndex()); |
| 272 | scope_info->set(index++, *isolate->factory()->this_string()); |
| 273 | DCHECK(index == scope_info->ContextLocalInfoEntriesIndex()); |
| 274 | const uint32_t value = ContextLocalMode::encode(CONST) | |
| 275 | ContextLocalInitFlag::encode(kCreatedInitialized) | |
| 276 | ContextLocalMaybeAssignedFlag::encode(kNotAssigned); |
| 277 | scope_info->set(index++, Smi::FromInt(value)); |
| 278 | |
| 279 | DCHECK(index == scope_info->StrongModeFreeVariableNameEntriesIndex()); |
| 280 | DCHECK(index == scope_info->StrongModeFreeVariablePositionEntriesIndex()); |
| 281 | |
| 282 | // And here we record that this scopeinfo binds a receiver. |
| 283 | DCHECK(index == scope_info->ReceiverEntryIndex()); |
| 284 | const int receiver_index = Context::MIN_CONTEXT_SLOTS + 0; |
| 285 | scope_info->set(index++, Smi::FromInt(receiver_index)); |
| 286 | |
| 287 | DCHECK(index == scope_info->FunctionNameEntryIndex()); |
| 288 | |
| 289 | DCHECK_EQ(index, scope_info->length()); |
| 290 | DCHECK_EQ(scope_info->ParameterCount(), 0); |
| 291 | DCHECK_EQ(scope_info->ContextLength(), Context::MIN_CONTEXT_SLOTS + 1); |
| 292 | |
| 293 | return scope_info; |
| 294 | } |
| 295 | |
| 296 | |
| 297 | ScopeInfo* ScopeInfo::Empty(Isolate* isolate) { |
| 298 | return reinterpret_cast<ScopeInfo*>(isolate->heap()->empty_fixed_array()); |
| 299 | } |
| 300 | |
| 301 | |
| 302 | ScopeType ScopeInfo::scope_type() { |
| 303 | DCHECK(length() > 0); |
| 304 | return ScopeTypeField::decode(Flags()); |
| 305 | } |
| 306 | |
| 307 | |
| 308 | bool ScopeInfo::CallsEval() { |
| 309 | return length() > 0 && CallsEvalField::decode(Flags()); |
| 310 | } |
| 311 | |
| 312 | |
| 313 | LanguageMode ScopeInfo::language_mode() { |
| 314 | return length() > 0 ? LanguageModeField::decode(Flags()) : SLOPPY; |
| 315 | } |
| 316 | |
| 317 | |
| 318 | bool ScopeInfo::is_declaration_scope() { |
| 319 | return DeclarationScopeField::decode(Flags()); |
| 320 | } |
| 321 | |
| 322 | |
| 323 | int ScopeInfo::LocalCount() { |
| 324 | return StackLocalCount() + ContextLocalCount(); |
| 325 | } |
| 326 | |
| 327 | |
| 328 | int ScopeInfo::StackSlotCount() { |
| 329 | if (length() > 0) { |
| 330 | bool function_name_stack_slot = |
| 331 | FunctionVariableField::decode(Flags()) == STACK; |
| 332 | return StackLocalCount() + (function_name_stack_slot ? 1 : 0); |
| 333 | } |
| 334 | return 0; |
| 335 | } |
| 336 | |
| 337 | |
| 338 | int ScopeInfo::ContextLength() { |
| 339 | if (length() > 0) { |
| 340 | int context_locals = ContextLocalCount(); |
| 341 | int context_globals = ContextGlobalCount(); |
| 342 | bool function_name_context_slot = |
| 343 | FunctionVariableField::decode(Flags()) == CONTEXT; |
| 344 | bool has_context = context_locals > 0 || context_globals > 0 || |
| 345 | function_name_context_slot || |
| 346 | scope_type() == WITH_SCOPE || |
| 347 | (scope_type() == BLOCK_SCOPE && CallsSloppyEval() && |
| 348 | is_declaration_scope()) || |
| 349 | (scope_type() == FUNCTION_SCOPE && CallsSloppyEval()) || |
| 350 | scope_type() == MODULE_SCOPE; |
| 351 | |
| 352 | if (has_context) { |
| 353 | return Context::MIN_CONTEXT_SLOTS + context_locals + context_globals + |
| 354 | (function_name_context_slot ? 1 : 0); |
| 355 | } |
| 356 | } |
| 357 | return 0; |
| 358 | } |
| 359 | |
| 360 | |
| 361 | bool ScopeInfo::HasReceiver() { |
| 362 | if (length() > 0) { |
| 363 | return NONE != ReceiverVariableField::decode(Flags()); |
| 364 | } else { |
| 365 | return false; |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | |
| 370 | bool ScopeInfo::HasAllocatedReceiver() { |
| 371 | if (length() > 0) { |
| 372 | VariableAllocationInfo allocation = ReceiverVariableField::decode(Flags()); |
| 373 | return allocation == STACK || allocation == CONTEXT; |
| 374 | } else { |
| 375 | return false; |
| 376 | } |
| 377 | } |
| 378 | |
| 379 | |
| 380 | bool ScopeInfo::HasNewTarget() { return HasNewTargetField::decode(Flags()); } |
| 381 | |
| 382 | |
| 383 | bool ScopeInfo::HasFunctionName() { |
| 384 | if (length() > 0) { |
| 385 | return NONE != FunctionVariableField::decode(Flags()); |
| 386 | } else { |
| 387 | return false; |
| 388 | } |
| 389 | } |
| 390 | |
| 391 | |
| 392 | bool ScopeInfo::HasHeapAllocatedLocals() { |
| 393 | if (length() > 0) { |
| 394 | return ContextLocalCount() > 0; |
| 395 | } else { |
| 396 | return false; |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | |
| 401 | bool ScopeInfo::HasContext() { |
| 402 | return ContextLength() > 0; |
| 403 | } |
| 404 | |
| 405 | |
| 406 | String* ScopeInfo::FunctionName() { |
| 407 | DCHECK(HasFunctionName()); |
| 408 | return String::cast(get(FunctionNameEntryIndex())); |
| 409 | } |
| 410 | |
| 411 | |
| 412 | String* ScopeInfo::ParameterName(int var) { |
| 413 | DCHECK(0 <= var && var < ParameterCount()); |
| 414 | int info_index = ParameterEntriesIndex() + var; |
| 415 | return String::cast(get(info_index)); |
| 416 | } |
| 417 | |
| 418 | |
| 419 | String* ScopeInfo::LocalName(int var) { |
| 420 | DCHECK(0 <= var && var < LocalCount()); |
| 421 | DCHECK(StackLocalEntriesIndex() + StackLocalCount() == |
| 422 | ContextLocalNameEntriesIndex()); |
| 423 | int info_index = StackLocalEntriesIndex() + var; |
| 424 | return String::cast(get(info_index)); |
| 425 | } |
| 426 | |
| 427 | |
| 428 | String* ScopeInfo::StackLocalName(int var) { |
| 429 | DCHECK(0 <= var && var < StackLocalCount()); |
| 430 | int info_index = StackLocalEntriesIndex() + var; |
| 431 | return String::cast(get(info_index)); |
| 432 | } |
| 433 | |
| 434 | |
| 435 | int ScopeInfo::StackLocalIndex(int var) { |
| 436 | DCHECK(0 <= var && var < StackLocalCount()); |
| 437 | int first_slot_index = Smi::cast(get(StackLocalFirstSlotIndex()))->value(); |
| 438 | return first_slot_index + var; |
| 439 | } |
| 440 | |
| 441 | |
| 442 | String* ScopeInfo::ContextLocalName(int var) { |
| 443 | DCHECK(0 <= var && var < ContextLocalCount() + ContextGlobalCount()); |
| 444 | int info_index = ContextLocalNameEntriesIndex() + var; |
| 445 | return String::cast(get(info_index)); |
| 446 | } |
| 447 | |
| 448 | |
| 449 | VariableMode ScopeInfo::ContextLocalMode(int var) { |
| 450 | DCHECK(0 <= var && var < ContextLocalCount() + ContextGlobalCount()); |
| 451 | int info_index = ContextLocalInfoEntriesIndex() + var; |
| 452 | int value = Smi::cast(get(info_index))->value(); |
| 453 | return ContextLocalMode::decode(value); |
| 454 | } |
| 455 | |
| 456 | |
| 457 | InitializationFlag ScopeInfo::ContextLocalInitFlag(int var) { |
| 458 | DCHECK(0 <= var && var < ContextLocalCount() + ContextGlobalCount()); |
| 459 | int info_index = ContextLocalInfoEntriesIndex() + var; |
| 460 | int value = Smi::cast(get(info_index))->value(); |
| 461 | return ContextLocalInitFlag::decode(value); |
| 462 | } |
| 463 | |
| 464 | |
| 465 | MaybeAssignedFlag ScopeInfo::ContextLocalMaybeAssignedFlag(int var) { |
| 466 | DCHECK(0 <= var && var < ContextLocalCount() + ContextGlobalCount()); |
| 467 | int info_index = ContextLocalInfoEntriesIndex() + var; |
| 468 | int value = Smi::cast(get(info_index))->value(); |
| 469 | return ContextLocalMaybeAssignedFlag::decode(value); |
| 470 | } |
| 471 | |
| 472 | |
| 473 | bool ScopeInfo::LocalIsSynthetic(int var) { |
| 474 | DCHECK(0 <= var && var < LocalCount()); |
| 475 | // There's currently no flag stored on the ScopeInfo to indicate that a |
| 476 | // variable is a compiler-introduced temporary. However, to avoid conflict |
| 477 | // with user declarations, the current temporaries like .generator_object and |
| 478 | // .result start with a dot, so we can use that as a flag. It's a hack! |
| 479 | Handle<String> name(LocalName(var)); |
| 480 | return (name->length() > 0 && name->Get(0) == '.') || |
| 481 | name->Equals(*GetIsolate()->factory()->this_string()); |
| 482 | } |
| 483 | |
| 484 | |
| 485 | String* ScopeInfo::StrongModeFreeVariableName(int var) { |
| 486 | DCHECK(0 <= var && var < StrongModeFreeVariableCount()); |
| 487 | int info_index = StrongModeFreeVariableNameEntriesIndex() + var; |
| 488 | return String::cast(get(info_index)); |
| 489 | } |
| 490 | |
| 491 | |
| 492 | int ScopeInfo::StrongModeFreeVariableStartPosition(int var) { |
| 493 | DCHECK(0 <= var && var < StrongModeFreeVariableCount()); |
| 494 | int info_index = StrongModeFreeVariablePositionEntriesIndex() + var * 2; |
| 495 | int32_t value = 0; |
| 496 | bool ok = get(info_index)->ToInt32(&value); |
| 497 | USE(ok); |
| 498 | DCHECK(ok); |
| 499 | return value; |
| 500 | } |
| 501 | |
| 502 | |
| 503 | int ScopeInfo::StrongModeFreeVariableEndPosition(int var) { |
| 504 | DCHECK(0 <= var && var < StrongModeFreeVariableCount()); |
| 505 | int info_index = StrongModeFreeVariablePositionEntriesIndex() + var * 2 + 1; |
| 506 | int32_t value = 0; |
| 507 | bool ok = get(info_index)->ToInt32(&value); |
| 508 | USE(ok); |
| 509 | DCHECK(ok); |
| 510 | return value; |
| 511 | } |
| 512 | |
| 513 | |
| 514 | int ScopeInfo::StackSlotIndex(String* name) { |
| 515 | DCHECK(name->IsInternalizedString()); |
| 516 | if (length() > 0) { |
| 517 | int first_slot_index = Smi::cast(get(StackLocalFirstSlotIndex()))->value(); |
| 518 | int start = StackLocalEntriesIndex(); |
| 519 | int end = StackLocalEntriesIndex() + StackLocalCount(); |
| 520 | for (int i = start; i < end; ++i) { |
| 521 | if (name == get(i)) { |
| 522 | return i - start + first_slot_index; |
| 523 | } |
| 524 | } |
| 525 | } |
| 526 | return -1; |
| 527 | } |
| 528 | |
| 529 | |
| 530 | int ScopeInfo::ContextSlotIndex(Handle<ScopeInfo> scope_info, |
| 531 | Handle<String> name, VariableMode* mode, |
| 532 | InitializationFlag* init_flag, |
| 533 | MaybeAssignedFlag* maybe_assigned_flag) { |
| 534 | DCHECK(name->IsInternalizedString()); |
| 535 | DCHECK(mode != NULL); |
| 536 | DCHECK(init_flag != NULL); |
| 537 | if (scope_info->length() > 0) { |
| 538 | ContextSlotCache* context_slot_cache = |
| 539 | scope_info->GetIsolate()->context_slot_cache(); |
| 540 | int result = context_slot_cache->Lookup(*scope_info, *name, mode, init_flag, |
| 541 | maybe_assigned_flag); |
| 542 | if (result != ContextSlotCache::kNotFound) { |
| 543 | DCHECK(result < scope_info->ContextLength()); |
| 544 | return result; |
| 545 | } |
| 546 | |
| 547 | int start = scope_info->ContextLocalNameEntriesIndex(); |
| 548 | int end = scope_info->ContextLocalNameEntriesIndex() + |
| 549 | scope_info->ContextLocalCount(); |
| 550 | for (int i = start; i < end; ++i) { |
| 551 | if (*name == scope_info->get(i)) { |
| 552 | int var = i - start; |
| 553 | *mode = scope_info->ContextLocalMode(var); |
| 554 | *init_flag = scope_info->ContextLocalInitFlag(var); |
| 555 | *maybe_assigned_flag = scope_info->ContextLocalMaybeAssignedFlag(var); |
| 556 | result = Context::MIN_CONTEXT_SLOTS + var; |
| 557 | |
| 558 | context_slot_cache->Update(scope_info, name, *mode, *init_flag, |
| 559 | *maybe_assigned_flag, result); |
| 560 | DCHECK(result < scope_info->ContextLength()); |
| 561 | return result; |
| 562 | } |
| 563 | } |
| 564 | // Cache as not found. Mode, init flag and maybe assigned flag don't matter. |
| 565 | context_slot_cache->Update(scope_info, name, TEMPORARY, |
| 566 | kNeedsInitialization, kNotAssigned, -1); |
| 567 | } |
| 568 | return -1; |
| 569 | } |
| 570 | |
| 571 | |
| 572 | int ScopeInfo::ContextGlobalSlotIndex(Handle<ScopeInfo> scope_info, |
| 573 | Handle<String> name, VariableMode* mode, |
| 574 | InitializationFlag* init_flag, |
| 575 | MaybeAssignedFlag* maybe_assigned_flag) { |
| 576 | DCHECK(name->IsInternalizedString()); |
| 577 | DCHECK(mode != NULL); |
| 578 | DCHECK(init_flag != NULL); |
| 579 | if (scope_info->length() > 0) { |
| 580 | // This is to ensure that ContextLocalMode() and co. queries would work. |
| 581 | DCHECK_EQ(scope_info->ContextGlobalNameEntriesIndex(), |
| 582 | scope_info->ContextLocalNameEntriesIndex() + |
| 583 | scope_info->ContextLocalCount()); |
| 584 | int base = scope_info->ContextLocalNameEntriesIndex(); |
| 585 | int start = scope_info->ContextGlobalNameEntriesIndex(); |
| 586 | int end = scope_info->ContextGlobalNameEntriesIndex() + |
| 587 | scope_info->ContextGlobalCount(); |
| 588 | for (int i = start; i < end; ++i) { |
| 589 | if (*name == scope_info->get(i)) { |
| 590 | int var = i - base; |
| 591 | *mode = scope_info->ContextLocalMode(var); |
| 592 | *init_flag = scope_info->ContextLocalInitFlag(var); |
| 593 | *maybe_assigned_flag = scope_info->ContextLocalMaybeAssignedFlag(var); |
| 594 | int result = Context::MIN_CONTEXT_SLOTS + var; |
| 595 | DCHECK(result < scope_info->ContextLength()); |
| 596 | return result; |
| 597 | } |
| 598 | } |
| 599 | } |
| 600 | return -1; |
| 601 | } |
| 602 | |
| 603 | |
| 604 | String* ScopeInfo::ContextSlotName(int slot_index) { |
| 605 | int const var = slot_index - Context::MIN_CONTEXT_SLOTS; |
| 606 | DCHECK_LE(0, var); |
| 607 | DCHECK_LT(var, ContextLocalCount() + ContextGlobalCount()); |
| 608 | return ContextLocalName(var); |
| 609 | } |
| 610 | |
| 611 | |
| 612 | int ScopeInfo::ParameterIndex(String* name) { |
| 613 | DCHECK(name->IsInternalizedString()); |
| 614 | if (length() > 0) { |
| 615 | // We must read parameters from the end since for |
| 616 | // multiply declared parameters the value of the |
| 617 | // last declaration of that parameter is used |
| 618 | // inside a function (and thus we need to look |
| 619 | // at the last index). Was bug# 1110337. |
| 620 | int start = ParameterEntriesIndex(); |
| 621 | int end = ParameterEntriesIndex() + ParameterCount(); |
| 622 | for (int i = end - 1; i >= start; --i) { |
| 623 | if (name == get(i)) { |
| 624 | return i - start; |
| 625 | } |
| 626 | } |
| 627 | } |
| 628 | return -1; |
| 629 | } |
| 630 | |
| 631 | |
| 632 | int ScopeInfo::ReceiverContextSlotIndex() { |
| 633 | if (length() > 0 && ReceiverVariableField::decode(Flags()) == CONTEXT) |
| 634 | return Smi::cast(get(ReceiverEntryIndex()))->value(); |
| 635 | return -1; |
| 636 | } |
| 637 | |
| 638 | |
| 639 | int ScopeInfo::FunctionContextSlotIndex(String* name, VariableMode* mode) { |
| 640 | DCHECK(name->IsInternalizedString()); |
| 641 | DCHECK(mode != NULL); |
| 642 | if (length() > 0) { |
| 643 | if (FunctionVariableField::decode(Flags()) == CONTEXT && |
| 644 | FunctionName() == name) { |
| 645 | *mode = FunctionVariableMode::decode(Flags()); |
| 646 | return Smi::cast(get(FunctionNameEntryIndex() + 1))->value(); |
| 647 | } |
| 648 | } |
| 649 | return -1; |
| 650 | } |
| 651 | |
| 652 | |
| 653 | FunctionKind ScopeInfo::function_kind() { |
| 654 | return FunctionKindField::decode(Flags()); |
| 655 | } |
| 656 | |
| 657 | |
| 658 | int ScopeInfo::ParameterEntriesIndex() { |
| 659 | DCHECK(length() > 0); |
| 660 | return kVariablePartIndex; |
| 661 | } |
| 662 | |
| 663 | |
| 664 | int ScopeInfo::StackLocalFirstSlotIndex() { |
| 665 | return ParameterEntriesIndex() + ParameterCount(); |
| 666 | } |
| 667 | |
| 668 | |
| 669 | int ScopeInfo::StackLocalEntriesIndex() { |
| 670 | return StackLocalFirstSlotIndex() + 1; |
| 671 | } |
| 672 | |
| 673 | |
| 674 | int ScopeInfo::ContextLocalNameEntriesIndex() { |
| 675 | return StackLocalEntriesIndex() + StackLocalCount(); |
| 676 | } |
| 677 | |
| 678 | |
| 679 | int ScopeInfo::ContextGlobalNameEntriesIndex() { |
| 680 | return ContextLocalNameEntriesIndex() + ContextLocalCount(); |
| 681 | } |
| 682 | |
| 683 | |
| 684 | int ScopeInfo::ContextLocalInfoEntriesIndex() { |
| 685 | return ContextGlobalNameEntriesIndex() + ContextGlobalCount(); |
| 686 | } |
| 687 | |
| 688 | |
| 689 | int ScopeInfo::ContextGlobalInfoEntriesIndex() { |
| 690 | return ContextLocalInfoEntriesIndex() + ContextLocalCount(); |
| 691 | } |
| 692 | |
| 693 | |
| 694 | int ScopeInfo::StrongModeFreeVariableNameEntriesIndex() { |
| 695 | return ContextGlobalInfoEntriesIndex() + ContextGlobalCount(); |
| 696 | } |
| 697 | |
| 698 | |
| 699 | int ScopeInfo::StrongModeFreeVariablePositionEntriesIndex() { |
| 700 | return StrongModeFreeVariableNameEntriesIndex() + |
| 701 | StrongModeFreeVariableCount(); |
| 702 | } |
| 703 | |
| 704 | |
| 705 | int ScopeInfo::ReceiverEntryIndex() { |
| 706 | return StrongModeFreeVariablePositionEntriesIndex() + |
| 707 | 2 * StrongModeFreeVariableCount(); |
| 708 | } |
| 709 | |
| 710 | |
| 711 | int ScopeInfo::FunctionNameEntryIndex() { |
| 712 | return ReceiverEntryIndex() + (HasAllocatedReceiver() ? 1 : 0); |
| 713 | } |
| 714 | |
| 715 | |
| 716 | int ContextSlotCache::Hash(Object* data, String* name) { |
| 717 | // Uses only lower 32 bits if pointers are larger. |
| 718 | uintptr_t addr_hash = |
| 719 | static_cast<uint32_t>(reinterpret_cast<uintptr_t>(data)) >> 2; |
| 720 | return static_cast<int>((addr_hash ^ name->Hash()) % kLength); |
| 721 | } |
| 722 | |
| 723 | |
| 724 | int ContextSlotCache::Lookup(Object* data, String* name, VariableMode* mode, |
| 725 | InitializationFlag* init_flag, |
| 726 | MaybeAssignedFlag* maybe_assigned_flag) { |
| 727 | int index = Hash(data, name); |
| 728 | Key& key = keys_[index]; |
| 729 | if ((key.data == data) && key.name->Equals(name)) { |
| 730 | Value result(values_[index]); |
| 731 | if (mode != NULL) *mode = result.mode(); |
| 732 | if (init_flag != NULL) *init_flag = result.initialization_flag(); |
| 733 | if (maybe_assigned_flag != NULL) |
| 734 | *maybe_assigned_flag = result.maybe_assigned_flag(); |
| 735 | return result.index() + kNotFound; |
| 736 | } |
| 737 | return kNotFound; |
| 738 | } |
| 739 | |
| 740 | |
| 741 | void ContextSlotCache::Update(Handle<Object> data, Handle<String> name, |
| 742 | VariableMode mode, InitializationFlag init_flag, |
| 743 | MaybeAssignedFlag maybe_assigned_flag, |
| 744 | int slot_index) { |
| 745 | DisallowHeapAllocation no_gc; |
| 746 | Handle<String> internalized_name; |
| 747 | DCHECK(slot_index > kNotFound); |
| 748 | if (StringTable::InternalizeStringIfExists(name->GetIsolate(), name). |
| 749 | ToHandle(&internalized_name)) { |
| 750 | int index = Hash(*data, *internalized_name); |
| 751 | Key& key = keys_[index]; |
| 752 | key.data = *data; |
| 753 | key.name = *internalized_name; |
| 754 | // Please note value only takes a uint as index. |
| 755 | values_[index] = Value(mode, init_flag, maybe_assigned_flag, |
| 756 | slot_index - kNotFound).raw(); |
| 757 | #ifdef DEBUG |
| 758 | ValidateEntry(data, name, mode, init_flag, maybe_assigned_flag, slot_index); |
| 759 | #endif |
| 760 | } |
| 761 | } |
| 762 | |
| 763 | |
| 764 | void ContextSlotCache::Clear() { |
| 765 | for (int index = 0; index < kLength; index++) keys_[index].data = NULL; |
| 766 | } |
| 767 | |
| 768 | |
| 769 | #ifdef DEBUG |
| 770 | |
| 771 | void ContextSlotCache::ValidateEntry(Handle<Object> data, Handle<String> name, |
| 772 | VariableMode mode, |
| 773 | InitializationFlag init_flag, |
| 774 | MaybeAssignedFlag maybe_assigned_flag, |
| 775 | int slot_index) { |
| 776 | DisallowHeapAllocation no_gc; |
| 777 | Handle<String> internalized_name; |
| 778 | if (StringTable::InternalizeStringIfExists(name->GetIsolate(), name). |
| 779 | ToHandle(&internalized_name)) { |
| 780 | int index = Hash(*data, *name); |
| 781 | Key& key = keys_[index]; |
| 782 | DCHECK(key.data == *data); |
| 783 | DCHECK(key.name->Equals(*name)); |
| 784 | Value result(values_[index]); |
| 785 | DCHECK(result.mode() == mode); |
| 786 | DCHECK(result.initialization_flag() == init_flag); |
| 787 | DCHECK(result.maybe_assigned_flag() == maybe_assigned_flag); |
| 788 | DCHECK(result.index() + kNotFound == slot_index); |
| 789 | } |
| 790 | } |
| 791 | |
| 792 | |
| 793 | static void PrintList(const char* list_name, |
| 794 | int nof_internal_slots, |
| 795 | int start, |
| 796 | int end, |
| 797 | ScopeInfo* scope_info) { |
| 798 | if (start < end) { |
| 799 | PrintF("\n // %s\n", list_name); |
| 800 | if (nof_internal_slots > 0) { |
| 801 | PrintF(" %2d - %2d [internal slots]\n", 0 , nof_internal_slots - 1); |
| 802 | } |
| 803 | for (int i = nof_internal_slots; start < end; ++i, ++start) { |
| 804 | PrintF(" %2d ", i); |
| 805 | String::cast(scope_info->get(start))->ShortPrint(); |
| 806 | PrintF("\n"); |
| 807 | } |
| 808 | } |
| 809 | } |
| 810 | |
| 811 | |
| 812 | void ScopeInfo::Print() { |
| 813 | PrintF("ScopeInfo "); |
| 814 | if (HasFunctionName()) { |
| 815 | FunctionName()->ShortPrint(); |
| 816 | } else { |
| 817 | PrintF("/* no function name */"); |
| 818 | } |
| 819 | PrintF("{"); |
| 820 | |
| 821 | if (length() > 0) { |
| 822 | PrintList("parameters", 0, ParameterEntriesIndex(), |
| 823 | ParameterEntriesIndex() + ParameterCount(), this); |
| 824 | PrintList("stack slots", 0, StackLocalEntriesIndex(), |
| 825 | StackLocalEntriesIndex() + StackLocalCount(), this); |
| 826 | PrintList("context slots", Context::MIN_CONTEXT_SLOTS, |
| 827 | ContextLocalNameEntriesIndex(), |
| 828 | ContextLocalNameEntriesIndex() + ContextLocalCount(), this); |
| 829 | } |
| 830 | |
| 831 | PrintF("}\n"); |
| 832 | } |
| 833 | #endif // DEBUG |
| 834 | |
| 835 | |
| 836 | //--------------------------------------------------------------------------- |
| 837 | // ModuleInfo. |
| 838 | |
| 839 | Handle<ModuleInfo> ModuleInfo::Create(Isolate* isolate, |
| 840 | ModuleDescriptor* descriptor, |
| 841 | Scope* scope) { |
| 842 | Handle<ModuleInfo> info = Allocate(isolate, descriptor->Length()); |
| 843 | info->set_host_index(descriptor->Index()); |
| 844 | int i = 0; |
| 845 | for (ModuleDescriptor::Iterator it = descriptor->iterator(); !it.done(); |
| 846 | it.Advance(), ++i) { |
| 847 | Variable* var = scope->LookupLocal(it.local_name()); |
| 848 | info->set_name(i, *(it.export_name()->string())); |
| 849 | info->set_mode(i, var->mode()); |
| 850 | DCHECK(var->index() >= 0); |
| 851 | info->set_index(i, var->index()); |
| 852 | } |
| 853 | DCHECK(i == info->length()); |
| 854 | return info; |
| 855 | } |
| 856 | |
| 857 | } // namespace internal |
| 858 | } // namespace v8 |