jit/JIT.cpp

   1 /*
   2  * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "JIT.h"
  28
  29 // This probably does not belong here; adding here for now as a quick Windows build fix.
  30 #if ENABLE(ASSEMBLER) && CPU(X86) && !OS(MAC_OS_X)
  31 #include "MacroAssembler.h"
  32 JSC::MacroAssemblerX86Common::SSE2CheckState JSC::MacroAssemblerX86Common::s_sse2CheckState = NotCheckedSSE2;
  33 #endif
  34
  35 #if ENABLE(JIT)
  36
  37 #include "CodeBlock.h"
  38 #include "Interpreter.h"
  39 #include "JITInlineMethods.h"
  40 #include "JITStubCall.h"
  41 #include "JSArray.h"
  42 #include "JSFunction.h"
  43 #include "LinkBuffer.h"
  44 #include "RepatchBuffer.h"
  45 #include "ResultType.h"
  46 #include "SamplingTool.h"
  47
  48 #ifndef NDEBUG
  49 #include <stdio.h>
  50 #endif
  51
  52 using namespace std;
  53
  54 namespace JSC {
  55
  56 void ctiPatchNearCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction)
  57 {
  58     RepatchBuffer repatchBuffer(codeblock);
  59     repatchBuffer.relinkNearCallerToTrampoline(returnAddress, newCalleeFunction);
  60 }
  61
  62 void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction)
  63 {
  64     RepatchBuffer repatchBuffer(codeblock);
  65     repatchBuffer.relinkCallerToTrampoline(returnAddress, newCalleeFunction);
  66 }
  67
  68 void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, FunctionPtr newCalleeFunction)
  69 {
  70     RepatchBuffer repatchBuffer(codeblock);
  71     repatchBuffer.relinkCallerToFunction(returnAddress, newCalleeFunction);
  72 }
  73
  74 JIT::JIT(JSGlobalData* globalData, CodeBlock* codeBlock, void* linkerOffset)
  75     : m_interpreter(globalData->interpreter)
  76     , m_globalData(globalData)
  77     , m_codeBlock(codeBlock)
  78     , m_labels(codeBlock ? codeBlock->instructions().size() : 0)
  79     , m_propertyAccessCompilationInfo(codeBlock ? codeBlock->numberOfStructureStubInfos() : 0)
  80     , m_callStructureStubCompilationInfo(codeBlock ? codeBlock->numberOfCallLinkInfos() : 0)
  81     , m_bytecodeIndex((unsigned)-1)
  82 #if USE(JSVALUE32_64)
  83     , m_jumpTargetIndex(0)
  84     , m_mappedBytecodeIndex((unsigned)-1)
  85     , m_mappedVirtualRegisterIndex((unsigned)-1)
  86     , m_mappedTag((RegisterID)-1)
  87     , m_mappedPayload((RegisterID)-1)
  88 #else
  89     , m_lastResultBytecodeRegister(std::numeric_limits<int>::max())
  90     , m_jumpTargetsPosition(0)
  91 #endif
  92     , m_linkerOffset(linkerOffset)
  93 {
  94 }
  95
  96 #if USE(JSVALUE32_64)
  97 void JIT::emitTimeoutCheck()
  98 {
  99     Jump skipTimeout = branchSub32(NonZero, Imm32(1), timeoutCheckRegister);
 100     JITStubCall stubCall(this, cti_timeout_check);
 101     stubCall.addArgument(regT1, regT0); // save last result registers.
 102     stubCall.call(timeoutCheckRegister);
 103     stubCall.getArgument(0, regT1, regT0); // reload last result registers.
 104     skipTimeout.link(this);
 105 }
 106 #else
 107 void JIT::emitTimeoutCheck()
 108 {
 109     Jump skipTimeout = branchSub32(NonZero, Imm32(1), timeoutCheckRegister);
 110     JITStubCall(this, cti_timeout_check).call(timeoutCheckRegister);
 111     skipTimeout.link(this);
 112
 113     killLastResultRegister();
 114 }
 115 #endif
 116
 117 #define NEXT_OPCODE(name) \
 118     m_bytecodeIndex += OPCODE_LENGTH(name); \
 119     break;
 120
 121 #if USE(JSVALUE32_64)
 122 #define DEFINE_BINARY_OP(name) \
 123     case name: { \
 124         JITStubCall stubCall(this, cti_##name); \
 125         stubCall.addArgument(currentInstruction[2].u.operand); \
 126         stubCall.addArgument(currentInstruction[3].u.operand); \
 127         stubCall.call(currentInstruction[1].u.operand); \
 128         NEXT_OPCODE(name); \
 129     }
 130
 131 #define DEFINE_UNARY_OP(name) \
 132     case name: { \
 133         JITStubCall stubCall(this, cti_##name); \
 134         stubCall.addArgument(currentInstruction[2].u.operand); \
 135         stubCall.call(currentInstruction[1].u.operand); \
 136         NEXT_OPCODE(name); \
 137     }
 138
 139 #else // USE(JSVALUE32_64)
 140
 141 #define DEFINE_BINARY_OP(name) \
 142     case name: { \
 143         JITStubCall stubCall(this, cti_##name); \
 144         stubCall.addArgument(currentInstruction[2].u.operand, regT2); \
 145         stubCall.addArgument(currentInstruction[3].u.operand, regT2); \
 146         stubCall.call(currentInstruction[1].u.operand); \
 147         NEXT_OPCODE(name); \
 148     }
 149
 150 #define DEFINE_UNARY_OP(name) \
 151     case name: { \
 152         JITStubCall stubCall(this, cti_##name); \
 153         stubCall.addArgument(currentInstruction[2].u.operand, regT2); \
 154         stubCall.call(currentInstruction[1].u.operand); \
 155         NEXT_OPCODE(name); \
 156     }
 157 #endif // USE(JSVALUE32_64)
 158
 159 #define DEFINE_OP(name) \
 160     case name: { \
 161         emit_##name(currentInstruction); \
 162         NEXT_OPCODE(name); \
 163     }
 164
 165 #define DEFINE_SLOWCASE_OP(name) \
 166     case name: { \
 167         emitSlow_##name(currentInstruction, iter); \
 168         NEXT_OPCODE(name); \
 169     }
 170
 171 void JIT::privateCompileMainPass()
 172 {
 173     Instruction* instructionsBegin = m_codeBlock->instructions().begin();
 174     unsigned instructionCount = m_codeBlock->instructions().size();
 175
 176     m_propertyAccessInstructionIndex = 0;
 177     m_globalResolveInfoIndex = 0;
 178     m_callLinkInfoIndex = 0;
 179
 180     for (m_bytecodeIndex = 0; m_bytecodeIndex < instructionCount; ) {
 181         Instruction* currentInstruction = instructionsBegin + m_bytecodeIndex;
 182         ASSERT_WITH_MESSAGE(m_interpreter->isOpcode(currentInstruction->u.opcode), "privateCompileMainPass gone bad @ %d", m_bytecodeIndex);
 183
 184 #if ENABLE(OPCODE_SAMPLING)
 185         if (m_bytecodeIndex > 0) // Avoid the overhead of sampling op_enter twice.
 186             sampleInstruction(currentInstruction);
 187 #endif
 188
 189 #if !USE(JSVALUE32_64)
 190         if (m_labels[m_bytecodeIndex].isUsed())
 191             killLastResultRegister();
 192 #endif
 193
 194         m_labels[m_bytecodeIndex] = label();
 195
 196         switch (m_interpreter->getOpcodeID(currentInstruction->u.opcode)) {
 197         DEFINE_BINARY_OP(op_del_by_val)
 198 #if USE(JSVALUE32)
 199         DEFINE_BINARY_OP(op_div)
 200 #endif
 201         DEFINE_BINARY_OP(op_in)
 202         DEFINE_BINARY_OP(op_less)
 203         DEFINE_BINARY_OP(op_lesseq)
 204         DEFINE_UNARY_OP(op_is_boolean)
 205         DEFINE_UNARY_OP(op_is_function)
 206         DEFINE_UNARY_OP(op_is_number)
 207         DEFINE_UNARY_OP(op_is_object)
 208         DEFINE_UNARY_OP(op_is_string)
 209         DEFINE_UNARY_OP(op_is_undefined)
 210 #if !USE(JSVALUE32_64)
 211         DEFINE_UNARY_OP(op_negate)
 212 #endif
 213         DEFINE_UNARY_OP(op_typeof)
 214
 215         DEFINE_OP(op_add)
 216         DEFINE_OP(op_bitand)
 217         DEFINE_OP(op_bitnot)
 218         DEFINE_OP(op_bitor)
 219         DEFINE_OP(op_bitxor)
 220         DEFINE_OP(op_call)
 221         DEFINE_OP(op_call_eval)
 222         DEFINE_OP(op_call_varargs)
 223         DEFINE_OP(op_catch)
 224         DEFINE_OP(op_construct)
 225         DEFINE_OP(op_construct_verify)
 226         DEFINE_OP(op_convert_this)
 227         DEFINE_OP(op_init_arguments)
 228         DEFINE_OP(op_create_arguments)
 229         DEFINE_OP(op_debug)
 230         DEFINE_OP(op_del_by_id)
 231 #if !USE(JSVALUE32)
 232         DEFINE_OP(op_div)
 233 #endif
 234         DEFINE_OP(op_end)
 235         DEFINE_OP(op_enter)
 236         DEFINE_OP(op_enter_with_activation)
 237         DEFINE_OP(op_eq)
 238         DEFINE_OP(op_eq_null)
 239         DEFINE_OP(op_get_by_id)
 240         DEFINE_OP(op_get_by_val)
 241         DEFINE_OP(op_get_by_pname)
 242         DEFINE_OP(op_get_global_var)
 243         DEFINE_OP(op_get_pnames)
 244         DEFINE_OP(op_get_scoped_var)
 245         DEFINE_OP(op_instanceof)
 246         DEFINE_OP(op_jeq_null)
 247         DEFINE_OP(op_jfalse)
 248         DEFINE_OP(op_jmp)
 249         DEFINE_OP(op_jmp_scopes)
 250         DEFINE_OP(op_jneq_null)
 251         DEFINE_OP(op_jneq_ptr)
 252         DEFINE_OP(op_jnless)
 253         DEFINE_OP(op_jless)
 254         DEFINE_OP(op_jlesseq)
 255         DEFINE_OP(op_jnlesseq)
 256         DEFINE_OP(op_jsr)
 257         DEFINE_OP(op_jtrue)
 258         DEFINE_OP(op_load_varargs)
 259         DEFINE_OP(op_loop)
 260         DEFINE_OP(op_loop_if_less)
 261         DEFINE_OP(op_loop_if_lesseq)
 262         DEFINE_OP(op_loop_if_true)
 263         DEFINE_OP(op_loop_if_false)
 264         DEFINE_OP(op_lshift)
 265         DEFINE_OP(op_method_check)
 266         DEFINE_OP(op_mod)
 267         DEFINE_OP(op_mov)
 268         DEFINE_OP(op_mul)
 269 #if USE(JSVALUE32_64)
 270         DEFINE_OP(op_negate)
 271 #endif
 272         DEFINE_OP(op_neq)
 273         DEFINE_OP(op_neq_null)
 274         DEFINE_OP(op_new_array)
 275         DEFINE_OP(op_new_error)
 276         DEFINE_OP(op_new_func)
 277         DEFINE_OP(op_new_func_exp)
 278         DEFINE_OP(op_new_object)
 279         DEFINE_OP(op_new_regexp)
 280         DEFINE_OP(op_next_pname)
 281         DEFINE_OP(op_not)
 282         DEFINE_OP(op_nstricteq)
 283         DEFINE_OP(op_pop_scope)
 284         DEFINE_OP(op_post_dec)
 285         DEFINE_OP(op_post_inc)
 286         DEFINE_OP(op_pre_dec)
 287         DEFINE_OP(op_pre_inc)
 288         DEFINE_OP(op_profile_did_call)
 289         DEFINE_OP(op_profile_will_call)
 290         DEFINE_OP(op_push_new_scope)
 291         DEFINE_OP(op_push_scope)
 292         DEFINE_OP(op_put_by_id)
 293         DEFINE_OP(op_put_by_index)
 294         DEFINE_OP(op_put_by_val)
 295         DEFINE_OP(op_put_getter)
 296         DEFINE_OP(op_put_global_var)
 297         DEFINE_OP(op_put_scoped_var)
 298         DEFINE_OP(op_put_setter)
 299         DEFINE_OP(op_resolve)
 300         DEFINE_OP(op_resolve_base)
 301         DEFINE_OP(op_resolve_global)
 302         DEFINE_OP(op_resolve_global_dynamic)
 303         DEFINE_OP(op_resolve_skip)
 304         DEFINE_OP(op_resolve_with_base)
 305         DEFINE_OP(op_ret)
 306         DEFINE_OP(op_rshift)
 307         DEFINE_OP(op_urshift)
 308         DEFINE_OP(op_sret)
 309         DEFINE_OP(op_strcat)
 310         DEFINE_OP(op_stricteq)
 311         DEFINE_OP(op_sub)
 312         DEFINE_OP(op_switch_char)
 313         DEFINE_OP(op_switch_imm)
 314         DEFINE_OP(op_switch_string)
 315         DEFINE_OP(op_tear_off_activation)
 316         DEFINE_OP(op_tear_off_arguments)
 317         DEFINE_OP(op_throw)
 318         DEFINE_OP(op_to_jsnumber)
 319         DEFINE_OP(op_to_primitive)
 320
 321         case op_get_array_length:
 322         case op_get_by_id_chain:
 323         case op_get_by_id_generic:
 324         case op_get_by_id_proto:
 325         case op_get_by_id_proto_list:
 326         case op_get_by_id_self:
 327         case op_get_by_id_self_list:
 328         case op_get_by_id_getter_chain:
 329         case op_get_by_id_getter_proto:
 330         case op_get_by_id_getter_proto_list:
 331         case op_get_by_id_getter_self:
 332         case op_get_by_id_getter_self_list:
 333         case op_get_by_id_custom_chain:
 334         case op_get_by_id_custom_proto:
 335         case op_get_by_id_custom_proto_list:
 336         case op_get_by_id_custom_self:
 337         case op_get_by_id_custom_self_list:
 338         case op_get_string_length:
 339         case op_put_by_id_generic:
 340         case op_put_by_id_replace:
 341         case op_put_by_id_transition:
 342             ASSERT_NOT_REACHED();
 343         }
 344     }
 345
 346     ASSERT(m_propertyAccessInstructionIndex == m_codeBlock->numberOfStructureStubInfos());
 347     ASSERT(m_callLinkInfoIndex == m_codeBlock->numberOfCallLinkInfos());
 348
 349 #ifndef NDEBUG
 350     // Reset this, in order to guard its use with ASSERTs.
 351     m_bytecodeIndex = (unsigned)-1;
 352 #endif
 353 }
 354
 355
 356 void JIT::privateCompileLinkPass()
 357 {
 358     unsigned jmpTableCount = m_jmpTable.size();
 359     for (unsigned i = 0; i < jmpTableCount; ++i)
 360         m_jmpTable[i].from.linkTo(m_labels[m_jmpTable[i].toBytecodeIndex], this);
 361     m_jmpTable.clear();
 362 }
 363
 364 void JIT::privateCompileSlowCases()
 365 {
 366     Instruction* instructionsBegin = m_codeBlock->instructions().begin();
 367
 368     m_propertyAccessInstructionIndex = 0;
 369     m_globalResolveInfoIndex = 0;
 370     m_callLinkInfoIndex = 0;
 371
 372     for (Vector<SlowCaseEntry>::iterator iter = m_slowCases.begin(); iter != m_slowCases.end();) {
 373 #if !USE(JSVALUE32_64)
 374         killLastResultRegister();
 375 #endif
 376
 377         m_bytecodeIndex = iter->to;
 378 #ifndef NDEBUG
 379         unsigned firstTo = m_bytecodeIndex;
 380 #endif
 381         Instruction* currentInstruction = instructionsBegin + m_bytecodeIndex;
 382
 383         switch (m_interpreter->getOpcodeID(currentInstruction->u.opcode)) {
 384         DEFINE_SLOWCASE_OP(op_add)
 385         DEFINE_SLOWCASE_OP(op_bitand)
 386         DEFINE_SLOWCASE_OP(op_bitnot)
 387         DEFINE_SLOWCASE_OP(op_bitor)
 388         DEFINE_SLOWCASE_OP(op_bitxor)
 389         DEFINE_SLOWCASE_OP(op_call)
 390         DEFINE_SLOWCASE_OP(op_call_eval)
 391         DEFINE_SLOWCASE_OP(op_call_varargs)
 392         DEFINE_SLOWCASE_OP(op_construct)
 393         DEFINE_SLOWCASE_OP(op_construct_verify)
 394         DEFINE_SLOWCASE_OP(op_convert_this)
 395 #if !USE(JSVALUE32)
 396         DEFINE_SLOWCASE_OP(op_div)
 397 #endif
 398         DEFINE_SLOWCASE_OP(op_eq)
 399         DEFINE_SLOWCASE_OP(op_get_by_id)
 400         DEFINE_SLOWCASE_OP(op_get_by_val)
 401         DEFINE_SLOWCASE_OP(op_get_by_pname)
 402         DEFINE_SLOWCASE_OP(op_instanceof)
 403         DEFINE_SLOWCASE_OP(op_jfalse)
 404         DEFINE_SLOWCASE_OP(op_jnless)
 405         DEFINE_SLOWCASE_OP(op_jless)
 406         DEFINE_SLOWCASE_OP(op_jlesseq)
 407         DEFINE_SLOWCASE_OP(op_jnlesseq)
 408         DEFINE_SLOWCASE_OP(op_jtrue)
 409         DEFINE_SLOWCASE_OP(op_loop_if_less)
 410         DEFINE_SLOWCASE_OP(op_loop_if_lesseq)
 411         DEFINE_SLOWCASE_OP(op_loop_if_true)
 412         DEFINE_SLOWCASE_OP(op_loop_if_false)
 413         DEFINE_SLOWCASE_OP(op_lshift)
 414         DEFINE_SLOWCASE_OP(op_method_check)
 415         DEFINE_SLOWCASE_OP(op_mod)
 416         DEFINE_SLOWCASE_OP(op_mul)
 417 #if USE(JSVALUE32_64)
 418         DEFINE_SLOWCASE_OP(op_negate)
 419 #endif
 420         DEFINE_SLOWCASE_OP(op_neq)
 421         DEFINE_SLOWCASE_OP(op_not)
 422         DEFINE_SLOWCASE_OP(op_nstricteq)
 423         DEFINE_SLOWCASE_OP(op_post_dec)
 424         DEFINE_SLOWCASE_OP(op_post_inc)
 425         DEFINE_SLOWCASE_OP(op_pre_dec)
 426         DEFINE_SLOWCASE_OP(op_pre_inc)
 427         DEFINE_SLOWCASE_OP(op_put_by_id)
 428         DEFINE_SLOWCASE_OP(op_put_by_val)
 429         DEFINE_SLOWCASE_OP(op_resolve_global)
 430         DEFINE_SLOWCASE_OP(op_resolve_global_dynamic)
 431         DEFINE_SLOWCASE_OP(op_rshift)
 432         DEFINE_SLOWCASE_OP(op_urshift)
 433         DEFINE_SLOWCASE_OP(op_stricteq)
 434         DEFINE_SLOWCASE_OP(op_sub)
 435         DEFINE_SLOWCASE_OP(op_to_jsnumber)
 436         DEFINE_SLOWCASE_OP(op_to_primitive)
 437         default:
 438             ASSERT_NOT_REACHED();
 439         }
 440
 441         ASSERT_WITH_MESSAGE(iter == m_slowCases.end() || firstTo != iter->to,"Not enough jumps linked in slow case codegen.");
 442         ASSERT_WITH_MESSAGE(firstTo == (iter - 1)->to, "Too many jumps linked in slow case codegen.");
 443
 444         emitJumpSlowToHot(jump(), 0);
 445     }
 446
 447 #if ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS)
 448     ASSERT(m_propertyAccessInstructionIndex == m_codeBlock->numberOfStructureStubInfos());
 449 #endif
 450     ASSERT(m_callLinkInfoIndex == m_codeBlock->numberOfCallLinkInfos());
 451
 452 #ifndef NDEBUG
 453     // Reset this, in order to guard its use with ASSERTs.
 454     m_bytecodeIndex = (unsigned)-1;
 455 #endif
 456 }
 457
 458 JITCode JIT::privateCompile()
 459 {
 460     sampleCodeBlock(m_codeBlock);
 461 #if ENABLE(OPCODE_SAMPLING)
 462     sampleInstruction(m_codeBlock->instructions().begin());
 463 #endif
 464
 465     // Could use a pop_m, but would need to offset the following instruction if so.
 466     preserveReturnAddressAfterCall(regT2);
 467     emitPutToCallFrameHeader(regT2, RegisterFile::ReturnPC);
 468
 469     Jump slowRegisterFileCheck;
 470     Label afterRegisterFileCheck;
 471     if (m_codeBlock->codeType() == FunctionCode) {
 472         // In the case of a fast linked call, we do not set this up in the caller.
 473         emitPutImmediateToCallFrameHeader(m_codeBlock, RegisterFile::CodeBlock);
 474
 475         peek(regT0, OBJECT_OFFSETOF(JITStackFrame, registerFile) / sizeof (void*));
 476         addPtr(Imm32(m_codeBlock->m_numCalleeRegisters * sizeof(Register)), callFrameRegister, regT1);
 477
 478         slowRegisterFileCheck = branchPtr(Above, regT1, Address(regT0, OBJECT_OFFSETOF(RegisterFile, m_end)));
 479         afterRegisterFileCheck = label();
 480     }
 481
 482     privateCompileMainPass();
 483     privateCompileLinkPass();
 484     privateCompileSlowCases();
 485
 486     if (m_codeBlock->codeType() == FunctionCode) {
 487         slowRegisterFileCheck.link(this);
 488         m_bytecodeIndex = 0;
 489         JITStubCall(this, cti_register_file_check).call();
 490 #ifndef NDEBUG
 491         m_bytecodeIndex = (unsigned)-1; // Reset this, in order to guard its use with ASSERTs.
 492 #endif
 493         jump(afterRegisterFileCheck);
 494     }
 495
 496     ASSERT(m_jmpTable.isEmpty());
 497
 498     RefPtr<ExecutablePool> executablePool = m_globalData->executableAllocator.poolForSize(m_assembler.size());
 499     if (!executablePool)
 500         return JITCode();
 501     LinkBuffer patchBuffer(this, executablePool.release(), m_linkerOffset);
 502
 503     // Translate vPC offsets into addresses in JIT generated code, for switch tables.
 504     for (unsigned i = 0; i < m_switches.size(); ++i) {
 505         SwitchRecord record = m_switches[i];
 506         unsigned bytecodeIndex = record.bytecodeIndex;
 507
 508         if (record.type != SwitchRecord::String) {
 509             ASSERT(record.type == SwitchRecord::Immediate || record.type == SwitchRecord::Character);
 510             ASSERT(record.jumpTable.simpleJumpTable->branchOffsets.size() == record.jumpTable.simpleJumpTable->ctiOffsets.size());
 511
 512             record.jumpTable.simpleJumpTable->ctiDefault = patchBuffer.locationOf(m_labels[bytecodeIndex + record.defaultOffset]);
 513
 514             for (unsigned j = 0; j < record.jumpTable.simpleJumpTable->branchOffsets.size(); ++j) {
 515                 unsigned offset = record.jumpTable.simpleJumpTable->branchOffsets[j];
 516                 record.jumpTable.simpleJumpTable->ctiOffsets[j] = offset ? patchBuffer.locationOf(m_labels[bytecodeIndex + offset]) : record.jumpTable.simpleJumpTable->ctiDefault;
 517             }
 518         } else {
 519             ASSERT(record.type == SwitchRecord::String);
 520
 521             record.jumpTable.stringJumpTable->ctiDefault = patchBuffer.locationOf(m_labels[bytecodeIndex + record.defaultOffset]);
 522
 523             StringJumpTable::StringOffsetTable::iterator end = record.jumpTable.stringJumpTable->offsetTable.end();
 524             for (StringJumpTable::StringOffsetTable::iterator it = record.jumpTable.stringJumpTable->offsetTable.begin(); it != end; ++it) {
 525                 unsigned offset = it->second.branchOffset;
 526                 it->second.ctiOffset = offset ? patchBuffer.locationOf(m_labels[bytecodeIndex + offset]) : record.jumpTable.stringJumpTable->ctiDefault;
 527             }
 528         }
 529     }
 530
 531     for (size_t i = 0; i < m_codeBlock->numberOfExceptionHandlers(); ++i) {
 532         HandlerInfo& handler = m_codeBlock->exceptionHandler(i);
 533         handler.nativeCode = patchBuffer.locationOf(m_labels[handler.target]);
 534     }
 535
 536     for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 537         if (iter->to)
 538             patchBuffer.link(iter->from, FunctionPtr(iter->to));
 539     }
 540
 541     if (m_codeBlock->hasExceptionInfo()) {
 542         m_codeBlock->callReturnIndexVector().reserveCapacity(m_calls.size());
 543         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter)
 544             m_codeBlock->callReturnIndexVector().append(CallReturnOffsetToBytecodeIndex(patchBuffer.returnAddressOffset(iter->from), iter->bytecodeIndex));
 545     }
 546
 547     // Link absolute addresses for jsr
 548     for (Vector<JSRInfo>::iterator iter = m_jsrSites.begin(); iter != m_jsrSites.end(); ++iter)
 549         patchBuffer.patch(iter->storeLocation, patchBuffer.locationOf(iter->target).executableAddress());
 550
 551 #if ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS)
 552     for (unsigned i = 0; i < m_codeBlock->numberOfStructureStubInfos(); ++i) {
 553         StructureStubInfo& info = m_codeBlock->structureStubInfo(i);
 554         info.callReturnLocation = patchBuffer.locationOf(m_propertyAccessCompilationInfo[i].callReturnLocation);
 555         info.hotPathBegin = patchBuffer.locationOf(m_propertyAccessCompilationInfo[i].hotPathBegin);
 556     }
 557 #endif
 558 #if ENABLE(JIT_OPTIMIZE_CALL)
 559     for (unsigned i = 0; i < m_codeBlock->numberOfCallLinkInfos(); ++i) {
 560         CallLinkInfo& info = m_codeBlock->callLinkInfo(i);
 561         info.ownerCodeBlock = m_codeBlock;
 562         info.callReturnLocation = patchBuffer.locationOfNearCall(m_callStructureStubCompilationInfo[i].callReturnLocation);
 563         info.hotPathBegin = patchBuffer.locationOf(m_callStructureStubCompilationInfo[i].hotPathBegin);
 564         info.hotPathOther = patchBuffer.locationOfNearCall(m_callStructureStubCompilationInfo[i].hotPathOther);
 565     }
 566 #endif
 567     unsigned methodCallCount = m_methodCallCompilationInfo.size();
 568     m_codeBlock->addMethodCallLinkInfos(methodCallCount);
 569     for (unsigned i = 0; i < methodCallCount; ++i) {
 570         MethodCallLinkInfo& info = m_codeBlock->methodCallLinkInfo(i);
 571         info.structureLabel = patchBuffer.locationOf(m_methodCallCompilationInfo[i].structureToCompare);
 572         info.callReturnLocation = m_codeBlock->structureStubInfo(m_methodCallCompilationInfo[i].propertyAccessIndex).callReturnLocation;
 573     }
 574
 575     return patchBuffer.finalizeCode();
 576 }
 577
 578 #if !USE(JSVALUE32_64)
 579 void JIT::emitGetVariableObjectRegister(RegisterID variableObject, int index, RegisterID dst)
 580 {
 581     loadPtr(Address(variableObject, OBJECT_OFFSETOF(JSVariableObject, d)), dst);
 582     loadPtr(Address(dst, OBJECT_OFFSETOF(JSVariableObject::JSVariableObjectData, registers)), dst);
 583     loadPtr(Address(dst, index * sizeof(Register)), dst);
 584 }
 585
 586 void JIT::emitPutVariableObjectRegister(RegisterID src, RegisterID variableObject, int index)
 587 {
 588     loadPtr(Address(variableObject, OBJECT_OFFSETOF(JSVariableObject, d)), variableObject);
 589     loadPtr(Address(variableObject, OBJECT_OFFSETOF(JSVariableObject::JSVariableObjectData, registers)), variableObject);
 590     storePtr(src, Address(variableObject, index * sizeof(Register)));
 591 }
 592 #endif
 593
 594 #if ENABLE(JIT_OPTIMIZE_CALL)
 595 void JIT::unlinkCall(CallLinkInfo* callLinkInfo)
 596 {
 597     // When the JSFunction is deleted the pointer embedded in the instruction stream will no longer be valid
 598     // (and, if a new JSFunction happened to be constructed at the same location, we could get a false positive
 599     // match).  Reset the check so it no longer matches.
 600     RepatchBuffer repatchBuffer(callLinkInfo->ownerCodeBlock);
 601 #if USE(JSVALUE32_64)
 602     repatchBuffer.repatch(callLinkInfo->hotPathBegin, 0);
 603 #else
 604     repatchBuffer.repatch(callLinkInfo->hotPathBegin, JSValue::encode(JSValue()));
 605 #endif
 606 }
 607
 608 void JIT::linkCall(JSFunction* callee, CodeBlock* callerCodeBlock, CodeBlock* calleeCodeBlock, JITCode& code, CallLinkInfo* callLinkInfo, int callerArgCount, JSGlobalData* globalData)
 609 {
 610     RepatchBuffer repatchBuffer(callerCodeBlock);
 611
 612     // Currently we only link calls with the exact number of arguments.
 613     // If this is a native call calleeCodeBlock is null so the number of parameters is unimportant
 614     if (!calleeCodeBlock || (callerArgCount == calleeCodeBlock->m_numParameters)) {
 615         ASSERT(!callLinkInfo->isLinked());
 616
 617         if (calleeCodeBlock)
 618             calleeCodeBlock->addCaller(callLinkInfo);
 619
 620         repatchBuffer.repatch(callLinkInfo->hotPathBegin, callee);
 621         repatchBuffer.relink(callLinkInfo->hotPathOther, code.addressForCall());
 622     }
 623
 624     // patch the call so we do not continue to try to link.
 625     repatchBuffer.relink(callLinkInfo->callReturnLocation, globalData->jitStubs->ctiVirtualCall());
 626 }
 627 #endif // ENABLE(JIT_OPTIMIZE_CALL)
 628
 629 } // namespace JSC
 630
 631 #endif // ENABLE(JIT)