bytecode/CodeBlock.h

   1 /*
   2  * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
   3  * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1.  Redistributions of source code must retain the above copyright
  10  *     notice, this list of conditions and the following disclaimer.
  11  * 2.  Redistributions in binary form must reproduce the above copyright
  12  *     notice, this list of conditions and the following disclaimer in the
  13  *     documentation and/or other materials provided with the distribution.
  14  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
  15  *     its contributors may be used to endorse or promote products derived
  16  *     from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #ifndef CodeBlock_h
  31 #define CodeBlock_h
  32
  33 #include "EvalCodeCache.h"
  34 #include "Instruction.h"
  35 #include "JSGlobalObject.h"
  36 #include "JumpTable.h"
  37 #include "Nodes.h"
  38 #include "RegExp.h"
  39 #include "UString.h"
  40 #include <wtf/RefPtr.h>
  41 #include <wtf/Vector.h>
  42
  43 #if ENABLE(JIT)
  44 #include "StructureStubInfo.h"
  45 #endif
  46
  47 namespace JSC {
  48
  49     class ExecState;
  50
  51     enum CodeType { GlobalCode, EvalCode, FunctionCode };
  52
  53     static ALWAYS_INLINE int missingThisObjectMarker() { return std::numeric_limits<int>::max(); }
  54
  55     struct HandlerInfo {
  56         uint32_t start;
  57         uint32_t end;
  58         uint32_t target;
  59         uint32_t scopeDepth;
  60 #if ENABLE(JIT)
  61         void* nativeCode;
  62 #endif
  63     };
  64
  65 #if ENABLE(JIT)
  66     // The code, and the associated pool from which it was allocated.
  67     struct JITCodeRef {
  68         void* code;
  69 #ifndef NDEBUG
  70         unsigned codeSize;
  71 #endif
  72         RefPtr<ExecutablePool> executablePool;
  73
  74         JITCodeRef()
  75             : code(0)
  76 #ifndef NDEBUG
  77             , codeSize(0)
  78 #endif
  79         {
  80         }
  81
  82         JITCodeRef(void* code, PassRefPtr<ExecutablePool> executablePool)
  83             : code(code)
  84 #ifndef NDEBUG
  85             , codeSize(0)
  86 #endif
  87             , executablePool(executablePool)
  88         {
  89         }
  90     };
  91 #endif
  92
  93     struct ExpressionRangeInfo {
  94         enum {
  95             MaxOffset = (1 << 7) - 1,
  96             MaxDivot = (1 << 25) - 1
  97         };
  98         uint32_t instructionOffset : 25;
  99         uint32_t divotPoint : 25;
 100         uint32_t startOffset : 7;
 101         uint32_t endOffset : 7;
 102     };
 103
 104     struct LineInfo {
 105         uint32_t instructionOffset;
 106         int32_t lineNumber;
 107     };
 108
 109     // Both op_construct and op_instanceof require a use of op_get_by_id to get
 110     // the prototype property from an object. The exception messages for exceptions
 111     // thrown by these instances op_get_by_id need to reflect this.
 112     struct GetByIdExceptionInfo {
 113         unsigned bytecodeOffset : 31;
 114         bool isOpConstruct : 1;
 115     };
 116
 117 #if ENABLE(JIT)
 118     struct CallLinkInfo {
 119         CallLinkInfo()
 120             : callReturnLocation(0)
 121             , hotPathBegin(0)
 122             , hotPathOther(0)
 123             , coldPathOther(0)
 124             , callee(0)
 125         {
 126         }
 127
 128         unsigned bytecodeIndex;
 129         void* callReturnLocation;
 130         void* hotPathBegin;
 131         void* hotPathOther;
 132         void* coldPathOther;
 133         CodeBlock* callee;
 134         unsigned position;
 135
 136         void setUnlinked() { callee = 0; }
 137         bool isLinked() { return callee; }
 138     };
 139
 140     struct FunctionRegisterInfo {
 141         FunctionRegisterInfo(unsigned bytecodeOffset, int functionRegisterIndex)
 142             : bytecodeOffset(bytecodeOffset)
 143             , functionRegisterIndex(functionRegisterIndex)
 144         {
 145         }
 146
 147         unsigned bytecodeOffset;
 148         int functionRegisterIndex;
 149     };
 150
 151     struct GlobalResolveInfo {
 152         GlobalResolveInfo(unsigned bytecodeOffset)
 153             : structure(0)
 154             , offset(0)
 155             , bytecodeOffset(bytecodeOffset)
 156         {
 157         }
 158
 159         Structure* structure;
 160         unsigned offset;
 161         unsigned bytecodeOffset;
 162     };
 163
 164     struct PC {
 165         PC(ptrdiff_t nativePCOffset, unsigned bytecodeIndex)
 166             : nativePCOffset(nativePCOffset)
 167             , bytecodeIndex(bytecodeIndex)
 168         {
 169         }
 170
 171         ptrdiff_t nativePCOffset;
 172         unsigned bytecodeIndex;
 173     };
 174
 175     // valueAtPosition helpers for the binaryChop algorithm below.
 176
 177     inline void* getStructureStubInfoReturnLocation(StructureStubInfo* structureStubInfo)
 178     {
 179         return structureStubInfo->callReturnLocation;
 180     }
 181
 182     inline void* getCallLinkInfoReturnLocation(CallLinkInfo* callLinkInfo)
 183     {
 184         return callLinkInfo->callReturnLocation;
 185     }
 186
 187     inline ptrdiff_t getNativePCOffset(PC* pc)
 188     {
 189         return pc->nativePCOffset;
 190     }
 191
 192     // Binary chop algorithm, calls valueAtPosition on pre-sorted elements in array,
 193     // compares result with key (KeyTypes should be comparable with '--', '<', '>').
 194     // Optimized for cases where the array contains the key, checked by assertions.
 195     template<typename ArrayType, typename KeyType, KeyType(*valueAtPosition)(ArrayType*)>
 196     inline ArrayType* binaryChop(ArrayType* array, size_t size, KeyType key)
 197     {
 198         // The array must contain at least one element (pre-condition, array does conatin key).
 199         // If the array only contains one element, no need to do the comparison.
 200         while (size > 1) {
 201             // Pick an element to check, half way through the array, and read the value.
 202             int pos = (size - 1) >> 1;
 203             KeyType val = valueAtPosition(&array[pos]);
 204
 205             // If the key matches, success!
 206             if (val == key)
 207                 return &array[pos];
 208             // The item we are looking for is smaller than the item being check; reduce the value of 'size',
 209             // chopping off the right hand half of the array.
 210             else if (key < val)
 211                 size = pos;
 212             // Discard all values in the left hand half of the array, up to and including the item at pos.
 213             else {
 214                 size -= (pos + 1);
 215                 array += (pos + 1);
 216             }
 217
 218             // 'size' should never reach zero.
 219             ASSERT(size);
 220         }
 221
 222         // If we reach this point we've chopped down to one element, no need to check it matches
 223         ASSERT(size == 1);
 224         ASSERT(key == valueAtPosition(&array[0]));
 225         return &array[0];
 226     }
 227 #endif
 228
 229     class CodeBlock {
 230         friend class JIT;
 231     public:
 232         CodeBlock(ScopeNode* ownerNode, CodeType, PassRefPtr<SourceProvider>, unsigned sourceOffset);
 233         ~CodeBlock();
 234
 235         void mark();
 236         void refStructures(Instruction* vPC) const;
 237         void derefStructures(Instruction* vPC) const;
 238 #if ENABLE(JIT)
 239         void unlinkCallers();
 240 #endif
 241
 242         static void dumpStatistics();
 243
 244 #if !defined(NDEBUG) || ENABLE_OPCODE_SAMPLING
 245         void dump(ExecState*) const;
 246         void printStructures(const Instruction*) const;
 247         void printStructure(const char* name, const Instruction*, int operand) const;
 248 #endif
 249
 250         inline bool isKnownNotImmediate(int index)
 251         {
 252             if (index == m_thisRegister)
 253                 return true;
 254
 255             if (isConstantRegisterIndex(index))
 256                 return getConstant(index).isCell();
 257
 258             return false;
 259         }
 260
 261         ALWAYS_INLINE bool isConstantRegisterIndex(int index)
 262         {
 263             return index >= m_numVars && index < m_numVars + m_numConstants;
 264         }
 265
 266         ALWAYS_INLINE JSValuePtr getConstant(int index)
 267         {
 268             return m_constantRegisters[index - m_numVars].getJSValue();
 269         }
 270
 271         ALWAYS_INLINE bool isTemporaryRegisterIndex(int index)
 272         {
 273             return index >= m_numVars + m_numConstants;
 274         }
 275
 276         HandlerInfo* handlerForBytecodeOffset(unsigned bytecodeOffset);
 277         int lineNumberForBytecodeOffset(CallFrame*, unsigned bytecodeOffset);
 278         int expressionRangeForBytecodeOffset(CallFrame*, unsigned bytecodeOffset, int& divot, int& startOffset, int& endOffset);
 279         bool getByIdExceptionInfoForBytecodeOffset(CallFrame*, unsigned bytecodeOffset, OpcodeID&);
 280
 281 #if ENABLE(JIT)
 282         void addCaller(CallLinkInfo* caller)
 283         {
 284             caller->callee = this;
 285             caller->position = m_linkedCallerList.size();
 286             m_linkedCallerList.append(caller);
 287         }
 288
 289         void removeCaller(CallLinkInfo* caller)
 290         {
 291             unsigned pos = caller->position;
 292             unsigned lastPos = m_linkedCallerList.size() - 1;
 293
 294             if (pos != lastPos) {
 295                 m_linkedCallerList[pos] = m_linkedCallerList[lastPos];
 296                 m_linkedCallerList[pos]->position = pos;
 297             }
 298             m_linkedCallerList.shrink(lastPos);
 299         }
 300
 301         StructureStubInfo& getStubInfo(void* returnAddress)
 302         {
 303             return *(binaryChop<StructureStubInfo, void*, getStructureStubInfoReturnLocation>(m_structureStubInfos.begin(), m_structureStubInfos.size(), returnAddress));
 304         }
 305
 306         CallLinkInfo& getCallLinkInfo(void* returnAddress)
 307         {
 308             return *(binaryChop<CallLinkInfo, void*, getCallLinkInfoReturnLocation>(m_callLinkInfos.begin(), m_callLinkInfos.size(), returnAddress));
 309         }
 310
 311         unsigned getBytecodeIndex(CallFrame* callFrame, void* nativePC)
 312         {
 313             reparseForExceptionInfoIfNecessary(callFrame);
 314             ptrdiff_t nativePCOffset = reinterpret_cast<void**>(nativePC) - reinterpret_cast<void**>(m_jitCode.code);
 315             return binaryChop<PC, ptrdiff_t, getNativePCOffset>(m_exceptionInfo->m_pcVector.begin(), m_exceptionInfo->m_pcVector.size(), nativePCOffset)->bytecodeIndex;
 316         }
 317
 318         bool functionRegisterForBytecodeOffset(unsigned bytecodeOffset, int& functionRegisterIndex);
 319 #endif
 320
 321         void setIsNumericCompareFunction(bool isNumericCompareFunction) { m_isNumericCompareFunction = isNumericCompareFunction; }
 322         bool isNumericCompareFunction() { return m_isNumericCompareFunction; }
 323
 324         Vector<Instruction>& instructions() { return m_instructions; }
 325 #ifndef NDEBUG
 326         void setInstructionCount(unsigned instructionCount) { m_instructionCount = instructionCount; }
 327 #endif
 328
 329 #if ENABLE(JIT)
 330         void setJITCode(JITCodeRef& jitCode);
 331         void* jitCode() { return m_jitCode.code; }
 332         ExecutablePool* executablePool() { return m_jitCode.executablePool.get(); }
 333 #endif
 334
 335         ScopeNode* ownerNode() const { return m_ownerNode; }
 336
 337         void setGlobalData(JSGlobalData* globalData) { m_globalData = globalData; }
 338
 339         void setThisRegister(int thisRegister) { m_thisRegister = thisRegister; }
 340         int thisRegister() const { return m_thisRegister; }
 341
 342         void setNeedsFullScopeChain(bool needsFullScopeChain) { m_needsFullScopeChain = needsFullScopeChain; }
 343         bool needsFullScopeChain() const { return m_needsFullScopeChain; }
 344         void setUsesEval(bool usesEval) { m_usesEval = usesEval; }
 345         bool usesEval() const { return m_usesEval; }
 346         void setUsesArguments(bool usesArguments) { m_usesArguments = usesArguments; }
 347         bool usesArguments() const { return m_usesArguments; }
 348
 349         CodeType codeType() const { return m_codeType; }
 350
 351         SourceProvider* source() const { return m_source.get(); }
 352         unsigned sourceOffset() const { return m_sourceOffset; }
 353
 354         size_t numberOfJumpTargets() const { return m_jumpTargets.size(); }
 355         void addJumpTarget(unsigned jumpTarget) { m_jumpTargets.append(jumpTarget); }
 356         unsigned jumpTarget(int index) const { return m_jumpTargets[index]; }
 357         unsigned lastJumpTarget() const { return m_jumpTargets.last(); }
 358
 359 #if !ENABLE(JIT)
 360         void addPropertyAccessInstruction(unsigned propertyAccessInstruction) { m_propertyAccessInstructions.append(propertyAccessInstruction); }
 361         void addGlobalResolveInstruction(unsigned globalResolveInstruction) { m_globalResolveInstructions.append(globalResolveInstruction); }
 362         bool hasGlobalResolveInstructionAtBytecodeOffset(unsigned bytecodeOffset);
 363 #else
 364         size_t numberOfStructureStubInfos() const { return m_structureStubInfos.size(); }
 365         void addStructureStubInfo(const StructureStubInfo& stubInfo) { m_structureStubInfos.append(stubInfo); }
 366         StructureStubInfo& structureStubInfo(int index) { return m_structureStubInfos[index]; }
 367
 368         void addGlobalResolveInfo(unsigned globalResolveInstruction) { m_globalResolveInfos.append(GlobalResolveInfo(globalResolveInstruction)); }
 369         GlobalResolveInfo& globalResolveInfo(int index) { return m_globalResolveInfos[index]; }
 370         bool hasGlobalResolveInfoAtBytecodeOffset(unsigned bytecodeOffset);
 371
 372         size_t numberOfCallLinkInfos() const { return m_callLinkInfos.size(); }
 373         void addCallLinkInfo() { m_callLinkInfos.append(CallLinkInfo()); }
 374         CallLinkInfo& callLinkInfo(int index) { return m_callLinkInfos[index]; }
 375
 376         void addFunctionRegisterInfo(unsigned bytecodeOffset, int functionIndex) { createRareDataIfNecessary(); m_rareData->m_functionRegisterInfos.append(FunctionRegisterInfo(bytecodeOffset, functionIndex)); }
 377 #endif
 378
 379         // Exception handling support
 380
 381         size_t numberOfExceptionHandlers() const { return m_rareData ? m_rareData->m_exceptionHandlers.size() : 0; }
 382         void addExceptionHandler(const HandlerInfo& hanler) { createRareDataIfNecessary(); return m_rareData->m_exceptionHandlers.append(hanler); }
 383         HandlerInfo& exceptionHandler(int index) { ASSERT(m_rareData); return m_rareData->m_exceptionHandlers[index]; }
 384
 385         bool hasExceptionInfo() const { return m_exceptionInfo; }
 386         void clearExceptionInfo() { m_exceptionInfo.clear(); }
 387
 388         void addExpressionInfo(const ExpressionRangeInfo& expressionInfo) { ASSERT(m_exceptionInfo); m_exceptionInfo->m_expressionInfo.append(expressionInfo); }
 389         void addGetByIdExceptionInfo(const GetByIdExceptionInfo& info) { ASSERT(m_exceptionInfo); m_exceptionInfo->m_getByIdExceptionInfo.append(info); }
 390
 391         size_t numberOfLineInfos() const { ASSERT(m_exceptionInfo); return m_exceptionInfo->m_lineInfo.size(); }
 392         void addLineInfo(const LineInfo& lineInfo) { ASSERT(m_exceptionInfo); m_exceptionInfo->m_lineInfo.append(lineInfo); }
 393         LineInfo& lastLineInfo() { ASSERT(m_exceptionInfo); return m_exceptionInfo->m_lineInfo.last(); }
 394
 395 #if ENABLE(JIT)
 396         Vector<PC>& pcVector() { ASSERT(m_exceptionInfo); return m_exceptionInfo->m_pcVector; }
 397 #endif
 398
 399         // Constant Pool
 400
 401         size_t numberOfIdentifiers() const { return m_identifiers.size(); }
 402         void addIdentifier(const Identifier& i) { return m_identifiers.append(i); }
 403         Identifier& identifier(int index) { return m_identifiers[index]; }
 404
 405         size_t numberOfConstantRegisters() const { return m_constantRegisters.size(); }
 406         void addConstantRegister(const Register& r) { return m_constantRegisters.append(r); }
 407         Register& constantRegister(int index) { return m_constantRegisters[index]; }
 408
 409         unsigned addFunctionExpression(FuncExprNode* n) { unsigned size = m_functionExpressions.size(); m_functionExpressions.append(n); return size; }
 410         FuncExprNode* functionExpression(int index) const { return m_functionExpressions[index].get(); }
 411
 412         unsigned addFunction(FuncDeclNode* n) { createRareDataIfNecessary(); unsigned size = m_rareData->m_functions.size(); m_rareData->m_functions.append(n); return size; }
 413         FuncDeclNode* function(int index) const { ASSERT(m_rareData); return m_rareData->m_functions[index].get(); }
 414
 415         bool hasFunctions() const { return m_functionExpressions.size() || (m_rareData && m_rareData->m_functions.size()); }
 416
 417         unsigned addUnexpectedConstant(JSValuePtr v) { createRareDataIfNecessary(); unsigned size = m_rareData->m_unexpectedConstants.size(); m_rareData->m_unexpectedConstants.append(v); return size; }
 418         JSValuePtr unexpectedConstant(int index) const { ASSERT(m_rareData); return m_rareData->m_unexpectedConstants[index]; }
 419
 420         unsigned addRegExp(RegExp* r) { createRareDataIfNecessary(); unsigned size = m_rareData->m_regexps.size(); m_rareData->m_regexps.append(r); return size; }
 421         RegExp* regexp(int index) const { ASSERT(m_rareData); return m_rareData->m_regexps[index].get(); }
 422
 423
 424         // Jump Tables
 425
 426         size_t numberOfImmediateSwitchJumpTables() const { return m_rareData ? m_rareData->m_immediateSwitchJumpTables.size() : 0; }
 427         SimpleJumpTable& addImmediateSwitchJumpTable() { createRareDataIfNecessary(); m_rareData->m_immediateSwitchJumpTables.append(SimpleJumpTable()); return m_rareData->m_immediateSwitchJumpTables.last(); }
 428         SimpleJumpTable& immediateSwitchJumpTable(int tableIndex) { ASSERT(m_rareData); return m_rareData->m_immediateSwitchJumpTables[tableIndex]; }
 429
 430         size_t numberOfCharacterSwitchJumpTables() const { return m_rareData ? m_rareData->m_characterSwitchJumpTables.size() : 0; }
 431         SimpleJumpTable& addCharacterSwitchJumpTable() { createRareDataIfNecessary(); m_rareData->m_characterSwitchJumpTables.append(SimpleJumpTable()); return m_rareData->m_characterSwitchJumpTables.last(); }
 432         SimpleJumpTable& characterSwitchJumpTable(int tableIndex) { ASSERT(m_rareData); return m_rareData->m_characterSwitchJumpTables[tableIndex]; }
 433
 434         size_t numberOfStringSwitchJumpTables() const { return m_rareData ? m_rareData->m_stringSwitchJumpTables.size() : 0; }
 435         StringJumpTable& addStringSwitchJumpTable() { createRareDataIfNecessary(); m_rareData->m_stringSwitchJumpTables.append(StringJumpTable()); return m_rareData->m_stringSwitchJumpTables.last(); }
 436         StringJumpTable& stringSwitchJumpTable(int tableIndex) { ASSERT(m_rareData); return m_rareData->m_stringSwitchJumpTables[tableIndex]; }
 437
 438
 439         SymbolTable& symbolTable() { return m_symbolTable; }
 440
 441         EvalCodeCache& evalCodeCache() { createRareDataIfNecessary(); return m_rareData->m_evalCodeCache; }
 442
 443         void shrinkToFit();
 444
 445         // FIXME: Make these remaining members private.
 446
 447         int m_numCalleeRegisters;
 448         // NOTE: numConstants holds the number of constant registers allocated
 449         // by the code generator, not the number of constant registers used.
 450         // (Duplicate constants are uniqued during code generation, and spare
 451         // constant registers may be allocated.)
 452         int m_numConstants;
 453         int m_numVars;
 454         int m_numParameters;
 455
 456     private:
 457 #if !defined(NDEBUG) || ENABLE(OPCODE_SAMPLING)
 458         void dump(ExecState*, const Vector<Instruction>::const_iterator& begin, Vector<Instruction>::const_iterator&) const;
 459 #endif
 460
 461         void reparseForExceptionInfoIfNecessary(CallFrame*);
 462
 463         void createRareDataIfNecessary()
 464         {
 465             if (!m_rareData)
 466                 m_rareData.set(new RareData);
 467         }
 468
 469         ScopeNode* m_ownerNode;
 470         JSGlobalData* m_globalData;
 471
 472         Vector<Instruction> m_instructions;
 473 #ifndef NDEBUG
 474         unsigned m_instructionCount;
 475 #endif
 476 #if ENABLE(JIT)
 477         JITCodeRef m_jitCode;
 478 #endif
 479
 480         int m_thisRegister;
 481
 482         bool m_needsFullScopeChain;
 483         bool m_usesEval;
 484         bool m_usesArguments;
 485         bool m_isNumericCompareFunction;
 486
 487         CodeType m_codeType;
 488
 489         RefPtr<SourceProvider> m_source;
 490         unsigned m_sourceOffset;
 491
 492 #if !ENABLE(JIT)
 493         Vector<unsigned> m_propertyAccessInstructions;
 494         Vector<unsigned> m_globalResolveInstructions;
 495 #else
 496         Vector<StructureStubInfo> m_structureStubInfos;
 497         Vector<GlobalResolveInfo> m_globalResolveInfos;
 498         Vector<CallLinkInfo> m_callLinkInfos;
 499         Vector<CallLinkInfo*> m_linkedCallerList;
 500 #endif
 501
 502         Vector<unsigned> m_jumpTargets;
 503
 504         // Constant Pool
 505         Vector<Identifier> m_identifiers;
 506         Vector<Register> m_constantRegisters;
 507         Vector<RefPtr<FuncExprNode> > m_functionExpressions;
 508
 509         SymbolTable m_symbolTable;
 510
 511         struct ExceptionInfo {
 512             Vector<ExpressionRangeInfo> m_expressionInfo;
 513             Vector<LineInfo> m_lineInfo;
 514             Vector<GetByIdExceptionInfo> m_getByIdExceptionInfo;
 515
 516 #if ENABLE(JIT)
 517             Vector<PC> m_pcVector;
 518 #endif
 519         };
 520         OwnPtr<ExceptionInfo> m_exceptionInfo;
 521
 522         struct RareData {
 523             Vector<HandlerInfo> m_exceptionHandlers;
 524
 525             // Rare Constants
 526             Vector<RefPtr<FuncDeclNode> > m_functions;
 527             Vector<JSValuePtr> m_unexpectedConstants;
 528             Vector<RefPtr<RegExp> > m_regexps;
 529
 530             // Jump Tables
 531             Vector<SimpleJumpTable> m_immediateSwitchJumpTables;
 532             Vector<SimpleJumpTable> m_characterSwitchJumpTables;
 533             Vector<StringJumpTable> m_stringSwitchJumpTables;
 534
 535             EvalCodeCache m_evalCodeCache;
 536
 537 #if ENABLE(JIT)
 538             Vector<FunctionRegisterInfo> m_functionRegisterInfos;
 539 #endif
 540         };
 541         OwnPtr<RareData> m_rareData;
 542     };
 543
 544     // Program code is not marked by any function, so we make the global object
 545     // responsible for marking it.
 546
 547     class ProgramCodeBlock : public CodeBlock {
 548     public:
 549         ProgramCodeBlock(ScopeNode* ownerNode, CodeType codeType, JSGlobalObject* globalObject, PassRefPtr<SourceProvider> sourceProvider)
 550             : CodeBlock(ownerNode, codeType, sourceProvider, 0)
 551             , m_globalObject(globalObject)
 552         {
 553             m_globalObject->codeBlocks().add(this);
 554         }
 555
 556         ~ProgramCodeBlock()
 557         {
 558             if (m_globalObject)
 559                 m_globalObject->codeBlocks().remove(this);
 560         }
 561
 562         void clearGlobalObject() { m_globalObject = 0; }
 563
 564     private:
 565         JSGlobalObject* m_globalObject; // For program and eval nodes, the global object that marks the constant pool.
 566     };
 567
 568     class EvalCodeBlock : public ProgramCodeBlock {
 569     public:
 570         EvalCodeBlock(ScopeNode* ownerNode, JSGlobalObject* globalObject, PassRefPtr<SourceProvider> sourceProvider, int baseScopeDepth)
 571             : ProgramCodeBlock(ownerNode, EvalCode, globalObject, sourceProvider)
 572             , m_baseScopeDepth(baseScopeDepth)
 573         {
 574         }
 575
 576         int baseScopeDepth() const { return m_baseScopeDepth; }
 577
 578     private:
 579         int m_baseScopeDepth;
 580     };
 581
 582 } // namespace JSC
 583
 584 #endif // CodeBlock_h