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) && PLATFORM(X86) && !PLATFORM(MAC)

    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 "JITStubs.h"

    41 #include "JITStubCall.h"

    42 #include "JSArray.h"

    43 #include "JSFunction.h"

    44 #include "LinkBuffer.h"

    45 #include "RepatchBuffer.h"

    46 #include "ResultType.h"

    47 #include "SamplingTool.h"

    48 

    49 #ifndef NDEBUG

    50 #include <stdio.h>

    51 #endif

    52 

    53 using namespace std;

    54 

    55 namespace JSC {

    56 

    57 void ctiPatchNearCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction)

    58 {

    59     RepatchBuffer repatchBuffer(codeblock);

    60     repatchBuffer.relinkNearCallerToTrampoline(returnAddress, newCalleeFunction);

    61 }

    62 

    63 void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction)

    64 {

    65     RepatchBuffer repatchBuffer(codeblock);

    66     repatchBuffer.relinkCallerToTrampoline(returnAddress, newCalleeFunction);

    67 }

    68 

    69 void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, FunctionPtr newCalleeFunction)

    70 {

    71     RepatchBuffer repatchBuffer(codeblock);

    72     repatchBuffer.relinkCallerToFunction(returnAddress, newCalleeFunction);

    73 }

    74 

    75 JIT::JIT(JSGlobalData* globalData, CodeBlock* codeBlock)

    76     : m_interpreter(globalData->interpreter)

    77     , m_globalData(globalData)

    78     , m_codeBlock(codeBlock)

    79     , m_labels(codeBlock ? codeBlock->instructions().size() : 0)

    80     , m_propertyAccessCompilationInfo(codeBlock ? codeBlock->numberOfStructureStubInfos() : 0)

    81     , m_callStructureStubCompilationInfo(codeBlock ? codeBlock->numberOfCallLinkInfos() : 0)

    82     , m_bytecodeIndex((unsigned)-1)

    83 #if USE(JSVALUE32_64)

    84     , m_jumpTargetIndex(0)

    85     , m_mappedBytecodeIndex((unsigned)-1)

    86     , m_mappedVirtualRegisterIndex((unsigned)-1)

    87     , m_mappedTag((RegisterID)-1)

    88     , m_mappedPayload((RegisterID)-1)

    89 #else

    90     , m_lastResultBytecodeRegister(std::numeric_limits<int>::max())

    91     , m_jumpTargetsPosition(0)

    92 #endif

    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_BINARY_OP(op_urshift)

   205         DEFINE_UNARY_OP(op_is_boolean)

   206         DEFINE_UNARY_OP(op_is_function)

   207         DEFINE_UNARY_OP(op_is_number)

   208         DEFINE_UNARY_OP(op_is_object)

   209         DEFINE_UNARY_OP(op_is_string)

   210         DEFINE_UNARY_OP(op_is_undefined)

   211 #if !USE(JSVALUE32_64)

   212         DEFINE_UNARY_OP(op_negate)

   213 #endif

   214         DEFINE_UNARY_OP(op_typeof)

   215 

   216         DEFINE_OP(op_add)

   217         DEFINE_OP(op_bitand)

   218         DEFINE_OP(op_bitnot)

   219         DEFINE_OP(op_bitor)

   220         DEFINE_OP(op_bitxor)

   221         DEFINE_OP(op_call)

   222         DEFINE_OP(op_call_eval)

   223         DEFINE_OP(op_call_varargs)

   224         DEFINE_OP(op_catch)

   225         DEFINE_OP(op_construct)

   226         DEFINE_OP(op_construct_verify)

   227         DEFINE_OP(op_convert_this)

   228         DEFINE_OP(op_init_arguments)

   229         DEFINE_OP(op_create_arguments)

   230         DEFINE_OP(op_debug)

   231         DEFINE_OP(op_del_by_id)

   232 #if !USE(JSVALUE32)

   233         DEFINE_OP(op_div)

   234 #endif

   235         DEFINE_OP(op_end)

   236         DEFINE_OP(op_enter)

   237         DEFINE_OP(op_enter_with_activation)

   238         DEFINE_OP(op_eq)

   239         DEFINE_OP(op_eq_null)

   240         DEFINE_OP(op_get_by_id)

   241         DEFINE_OP(op_get_by_val)

   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_jnlesseq)

   254         DEFINE_OP(op_jsr)

   255         DEFINE_OP(op_jtrue)

   256         DEFINE_OP(op_load_varargs)

   257         DEFINE_OP(op_loop)

   258         DEFINE_OP(op_loop_if_less)

   259         DEFINE_OP(op_loop_if_lesseq)

   260         DEFINE_OP(op_loop_if_true)

   261         DEFINE_OP(op_lshift)

   262         DEFINE_OP(op_method_check)

   263         DEFINE_OP(op_mod)

   264         DEFINE_OP(op_mov)

   265         DEFINE_OP(op_mul)

   266 #if USE(JSVALUE32_64)

   267         DEFINE_OP(op_negate)

   268 #endif

   269         DEFINE_OP(op_neq)

   270         DEFINE_OP(op_neq_null)

   271         DEFINE_OP(op_new_array)

   272         DEFINE_OP(op_new_error)

   273         DEFINE_OP(op_new_func)

   274         DEFINE_OP(op_new_func_exp)

   275         DEFINE_OP(op_new_object)

   276         DEFINE_OP(op_new_regexp)

   277         DEFINE_OP(op_next_pname)

   278         DEFINE_OP(op_not)

   279         DEFINE_OP(op_nstricteq)

   280         DEFINE_OP(op_pop_scope)

   281         DEFINE_OP(op_post_dec)

   282         DEFINE_OP(op_post_inc)

   283         DEFINE_OP(op_pre_dec)

   284         DEFINE_OP(op_pre_inc)

   285         DEFINE_OP(op_profile_did_call)

   286         DEFINE_OP(op_profile_will_call)

   287         DEFINE_OP(op_push_new_scope)

   288         DEFINE_OP(op_push_scope)

   289         DEFINE_OP(op_put_by_id)

   290         DEFINE_OP(op_put_by_index)

   291         DEFINE_OP(op_put_by_val)

   292         DEFINE_OP(op_put_getter)

   293         DEFINE_OP(op_put_global_var)

   294         DEFINE_OP(op_put_scoped_var)

   295         DEFINE_OP(op_put_setter)

   296         DEFINE_OP(op_resolve)

   297         DEFINE_OP(op_resolve_base)

   298         DEFINE_OP(op_resolve_global)

   299         DEFINE_OP(op_resolve_skip)

   300         DEFINE_OP(op_resolve_with_base)

   301         DEFINE_OP(op_ret)

   302         DEFINE_OP(op_rshift)

   303         DEFINE_OP(op_sret)

   304         DEFINE_OP(op_strcat)

   305         DEFINE_OP(op_stricteq)

   306         DEFINE_OP(op_sub)

   307         DEFINE_OP(op_switch_char)

   308         DEFINE_OP(op_switch_imm)

   309         DEFINE_OP(op_switch_string)

   310         DEFINE_OP(op_tear_off_activation)

   311         DEFINE_OP(op_tear_off_arguments)

   312         DEFINE_OP(op_throw)

   313         DEFINE_OP(op_to_jsnumber)

   314         DEFINE_OP(op_to_primitive)

   315 

   316         case op_get_array_length:

   317         case op_get_by_id_chain:

   318         case op_get_by_id_generic:

   319         case op_get_by_id_proto:

   320         case op_get_by_id_proto_list:

   321         case op_get_by_id_self:

   322         case op_get_by_id_self_list:

   323         case op_get_string_length:

   324         case op_put_by_id_generic:

   325         case op_put_by_id_replace:

   326         case op_put_by_id_transition:

   327             ASSERT_NOT_REACHED();

   328         }

   329     }

   330 

   331     ASSERT(m_propertyAccessInstructionIndex == m_codeBlock->numberOfStructureStubInfos());

   332     ASSERT(m_callLinkInfoIndex == m_codeBlock->numberOfCallLinkInfos());

   333 

   334 #ifndef NDEBUG

   335     // Reset this, in order to guard its use with ASSERTs.

   336     m_bytecodeIndex = (unsigned)-1;

   337 #endif

   338 }

   339 

   340 

   341 void JIT::privateCompileLinkPass()

   342 {

   343     unsigned jmpTableCount = m_jmpTable.size();

   344     for (unsigned i = 0; i < jmpTableCount; ++i)

   345         m_jmpTable[i].from.linkTo(m_labels[m_jmpTable[i].toBytecodeIndex], this);

   346     m_jmpTable.clear();

   347 }

   348 

   349 void JIT::privateCompileSlowCases()

   350 {

   351     Instruction* instructionsBegin = m_codeBlock->instructions().begin();

   352 

   353     m_propertyAccessInstructionIndex = 0;

   354 #if USE(JSVALUE32_64)

   355     m_globalResolveInfoIndex = 0;

   356 #endif

   357     m_callLinkInfoIndex = 0;

   358 

   359     for (Vector<SlowCaseEntry>::iterator iter = m_slowCases.begin(); iter != m_slowCases.end();) {

   360 #if !USE(JSVALUE32_64)

   361         killLastResultRegister();

   362 #endif

   363 

   364         m_bytecodeIndex = iter->to;

   365 #ifndef NDEBUG

   366         unsigned firstTo = m_bytecodeIndex;

   367 #endif

   368         Instruction* currentInstruction = instructionsBegin + m_bytecodeIndex;

   369 

   370         switch (m_interpreter->getOpcodeID(currentInstruction->u.opcode)) {

   371         DEFINE_SLOWCASE_OP(op_add)

   372         DEFINE_SLOWCASE_OP(op_bitand)

   373         DEFINE_SLOWCASE_OP(op_bitnot)

   374         DEFINE_SLOWCASE_OP(op_bitor)

   375         DEFINE_SLOWCASE_OP(op_bitxor)

   376         DEFINE_SLOWCASE_OP(op_call)

   377         DEFINE_SLOWCASE_OP(op_call_eval)

   378         DEFINE_SLOWCASE_OP(op_call_varargs)

   379         DEFINE_SLOWCASE_OP(op_construct)

   380         DEFINE_SLOWCASE_OP(op_construct_verify)

   381         DEFINE_SLOWCASE_OP(op_convert_this)

   382 #if !USE(JSVALUE32)

   383         DEFINE_SLOWCASE_OP(op_div)

   384 #endif

   385         DEFINE_SLOWCASE_OP(op_eq)

   386         DEFINE_SLOWCASE_OP(op_get_by_id)

   387         DEFINE_SLOWCASE_OP(op_get_by_val)

   388         DEFINE_SLOWCASE_OP(op_instanceof)

   389         DEFINE_SLOWCASE_OP(op_jfalse)

   390         DEFINE_SLOWCASE_OP(op_jnless)

   391         DEFINE_SLOWCASE_OP(op_jnlesseq)

   392         DEFINE_SLOWCASE_OP(op_jtrue)

   393         DEFINE_SLOWCASE_OP(op_loop_if_less)

   394         DEFINE_SLOWCASE_OP(op_loop_if_lesseq)

   395         DEFINE_SLOWCASE_OP(op_loop_if_true)

   396         DEFINE_SLOWCASE_OP(op_lshift)

   397         DEFINE_SLOWCASE_OP(op_method_check)

   398         DEFINE_SLOWCASE_OP(op_mod)

   399         DEFINE_SLOWCASE_OP(op_mul)

   400 #if USE(JSVALUE32_64)

   401         DEFINE_SLOWCASE_OP(op_negate)

   402 #endif

   403         DEFINE_SLOWCASE_OP(op_neq)

   404         DEFINE_SLOWCASE_OP(op_not)

   405         DEFINE_SLOWCASE_OP(op_nstricteq)

   406         DEFINE_SLOWCASE_OP(op_post_dec)

   407         DEFINE_SLOWCASE_OP(op_post_inc)

   408         DEFINE_SLOWCASE_OP(op_pre_dec)

   409         DEFINE_SLOWCASE_OP(op_pre_inc)

   410         DEFINE_SLOWCASE_OP(op_put_by_id)

   411         DEFINE_SLOWCASE_OP(op_put_by_val)

   412 #if USE(JSVALUE32_64)

   413         DEFINE_SLOWCASE_OP(op_resolve_global)

   414 #endif

   415         DEFINE_SLOWCASE_OP(op_rshift)

   416         DEFINE_SLOWCASE_OP(op_stricteq)

   417         DEFINE_SLOWCASE_OP(op_sub)

   418         DEFINE_SLOWCASE_OP(op_to_jsnumber)

   419         DEFINE_SLOWCASE_OP(op_to_primitive)

   420         default:

   421             ASSERT_NOT_REACHED();

   422         }

   423 

   424         ASSERT_WITH_MESSAGE(iter == m_slowCases.end() || firstTo != iter->to,"Not enough jumps linked in slow case codegen.");

   425         ASSERT_WITH_MESSAGE(firstTo == (iter - 1)->to, "Too many jumps linked in slow case codegen.");

   426 

   427         emitJumpSlowToHot(jump(), 0);

   428     }

   429 

   430 #if ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS)

   431     ASSERT(m_propertyAccessInstructionIndex == m_codeBlock->numberOfStructureStubInfos());

   432 #endif

   433     ASSERT(m_callLinkInfoIndex == m_codeBlock->numberOfCallLinkInfos());

   434 

   435 #ifndef NDEBUG

   436     // Reset this, in order to guard its use with ASSERTs.

   437     m_bytecodeIndex = (unsigned)-1;

   438 #endif

   439 }

   440 

   441 JITCode JIT::privateCompile()

   442 {

   443     sampleCodeBlock(m_codeBlock);

   444 #if ENABLE(OPCODE_SAMPLING)

   445     sampleInstruction(m_codeBlock->instructions().begin());

   446 #endif

   447 

   448     // Could use a pop_m, but would need to offset the following instruction if so.

   449     preserveReturnAddressAfterCall(regT2);

   450     emitPutToCallFrameHeader(regT2, RegisterFile::ReturnPC);

   451 

   452     Jump slowRegisterFileCheck;

   453     Label afterRegisterFileCheck;

   454     if (m_codeBlock->codeType() == FunctionCode) {

   455         // In the case of a fast linked call, we do not set this up in the caller.

   456         emitPutImmediateToCallFrameHeader(m_codeBlock, RegisterFile::CodeBlock);

   457 

   458         peek(regT0, OBJECT_OFFSETOF(JITStackFrame, registerFile) / sizeof (void*));

   459         addPtr(Imm32(m_codeBlock->m_numCalleeRegisters * sizeof(Register)), callFrameRegister, regT1);

   460 

   461         slowRegisterFileCheck = branchPtr(Above, regT1, Address(regT0, OBJECT_OFFSETOF(RegisterFile, m_end)));

   462         afterRegisterFileCheck = label();

   463     }

   464 

   465     privateCompileMainPass();

   466     privateCompileLinkPass();

   467     privateCompileSlowCases();

   468 

   469     if (m_codeBlock->codeType() == FunctionCode) {

   470         slowRegisterFileCheck.link(this);

   471         m_bytecodeIndex = 0;

   472         JITStubCall(this, cti_register_file_check).call();

   473 #ifndef NDEBUG

   474         m_bytecodeIndex = (unsigned)-1; // Reset this, in order to guard its use with ASSERTs.

   475 #endif

   476         jump(afterRegisterFileCheck);

   477     }

   478 

   479     ASSERT(m_jmpTable.isEmpty());

   480 

   481     LinkBuffer patchBuffer(this, m_globalData->executableAllocator.poolForSize(m_assembler.size()));

   482 

   483     // Translate vPC offsets into addresses in JIT generated code, for switch tables.

   484     for (unsigned i = 0; i < m_switches.size(); ++i) {

   485         SwitchRecord record = m_switches[i];

   486         unsigned bytecodeIndex = record.bytecodeIndex;

   487 

   488         if (record.type != SwitchRecord::String) {

   489             ASSERT(record.type == SwitchRecord::Immediate || record.type == SwitchRecord::Character); 

   490             ASSERT(record.jumpTable.simpleJumpTable->branchOffsets.size() == record.jumpTable.simpleJumpTable->ctiOffsets.size());

   491 

   492             record.jumpTable.simpleJumpTable->ctiDefault = patchBuffer.locationOf(m_labels[bytecodeIndex + record.defaultOffset]);

   493 

   494             for (unsigned j = 0; j < record.jumpTable.simpleJumpTable->branchOffsets.size(); ++j) {

   495                 unsigned offset = record.jumpTable.simpleJumpTable->branchOffsets[j];

   496                 record.jumpTable.simpleJumpTable->ctiOffsets[j] = offset ? patchBuffer.locationOf(m_labels[bytecodeIndex + offset]) : record.jumpTable.simpleJumpTable->ctiDefault;

   497             }

   498         } else {

   499             ASSERT(record.type == SwitchRecord::String);

   500 

   501             record.jumpTable.stringJumpTable->ctiDefault = patchBuffer.locationOf(m_labels[bytecodeIndex + record.defaultOffset]);

   502 

   503             StringJumpTable::StringOffsetTable::iterator end = record.jumpTable.stringJumpTable->offsetTable.end();            

   504             for (StringJumpTable::StringOffsetTable::iterator it = record.jumpTable.stringJumpTable->offsetTable.begin(); it != end; ++it) {

   505                 unsigned offset = it->second.branchOffset;

   506                 it->second.ctiOffset = offset ? patchBuffer.locationOf(m_labels[bytecodeIndex + offset]) : record.jumpTable.stringJumpTable->ctiDefault;

   507             }

   508         }

   509     }

   510 

   511     for (size_t i = 0; i < m_codeBlock->numberOfExceptionHandlers(); ++i) {

   512         HandlerInfo& handler = m_codeBlock->exceptionHandler(i);

   513         handler.nativeCode = patchBuffer.locationOf(m_labels[handler.target]);

   514     }

   515 

   516     for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {

   517         if (iter->to)

   518             patchBuffer.link(iter->from, FunctionPtr(iter->to));

   519     }

   520 

   521     if (m_codeBlock->hasExceptionInfo()) {

   522         m_codeBlock->callReturnIndexVector().reserveCapacity(m_calls.size());

   523         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter)

   524             m_codeBlock->callReturnIndexVector().append(CallReturnOffsetToBytecodeIndex(patchBuffer.returnAddressOffset(iter->from), iter->bytecodeIndex));

   525     }

   526 

   527     // Link absolute addresses for jsr

   528     for (Vector<JSRInfo>::iterator iter = m_jsrSites.begin(); iter != m_jsrSites.end(); ++iter)

   529         patchBuffer.patch(iter->storeLocation, patchBuffer.locationOf(iter->target).executableAddress());

   530 

   531 #if ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS)

   532     for (unsigned i = 0; i < m_codeBlock->numberOfStructureStubInfos(); ++i) {

   533         StructureStubInfo& info = m_codeBlock->structureStubInfo(i);

   534         info.callReturnLocation = patchBuffer.locationOf(m_propertyAccessCompilationInfo[i].callReturnLocation);

   535         info.hotPathBegin = patchBuffer.locationOf(m_propertyAccessCompilationInfo[i].hotPathBegin);

   536     }

   537 #endif

   538 #if ENABLE(JIT_OPTIMIZE_CALL)

   539     for (unsigned i = 0; i < m_codeBlock->numberOfCallLinkInfos(); ++i) {

   540         CallLinkInfo& info = m_codeBlock->callLinkInfo(i);

   541         info.ownerCodeBlock = m_codeBlock;

   542         info.callReturnLocation = patchBuffer.locationOfNearCall(m_callStructureStubCompilationInfo[i].callReturnLocation);

   543         info.hotPathBegin = patchBuffer.locationOf(m_callStructureStubCompilationInfo[i].hotPathBegin);

   544         info.hotPathOther = patchBuffer.locationOfNearCall(m_callStructureStubCompilationInfo[i].hotPathOther);

   545     }

   546 #endif

   547     unsigned methodCallCount = m_methodCallCompilationInfo.size();

   548     m_codeBlock->addMethodCallLinkInfos(methodCallCount);

   549     for (unsigned i = 0; i < methodCallCount; ++i) {

   550         MethodCallLinkInfo& info = m_codeBlock->methodCallLinkInfo(i);

   551         info.structureLabel = patchBuffer.locationOf(m_methodCallCompilationInfo[i].structureToCompare);

   552         info.callReturnLocation = m_codeBlock->structureStubInfo(m_methodCallCompilationInfo[i].propertyAccessIndex).callReturnLocation;

   553     }

   554 

   555     return patchBuffer.finalizeCode();

   556 }

   557 

   558 #if !USE(JSVALUE32_64)

   559 void JIT::emitGetVariableObjectRegister(RegisterID variableObject, int index, RegisterID dst)

   560 {

   561     loadPtr(Address(variableObject, OBJECT_OFFSETOF(JSVariableObject, d)), dst);

   562     loadPtr(Address(dst, OBJECT_OFFSETOF(JSVariableObject::JSVariableObjectData, registers)), dst);

   563     loadPtr(Address(dst, index * sizeof(Register)), dst);

   564 }

   565 

   566 void JIT::emitPutVariableObjectRegister(RegisterID src, RegisterID variableObject, int index)

   567 {

   568     loadPtr(Address(variableObject, OBJECT_OFFSETOF(JSVariableObject, d)), variableObject);

   569     loadPtr(Address(variableObject, OBJECT_OFFSETOF(JSVariableObject::JSVariableObjectData, registers)), variableObject);

   570     storePtr(src, Address(variableObject, index * sizeof(Register)));

   571 }

   572 #endif

   573 

   574 #if ENABLE(JIT_OPTIMIZE_CALL)

   575 void JIT::unlinkCall(CallLinkInfo* callLinkInfo)

   576 {

   577     // When the JSFunction is deleted the pointer embedded in the instruction stream will no longer be valid

   578     // (and, if a new JSFunction happened to be constructed at the same location, we could get a false positive

   579     // match).  Reset the check so it no longer matches.

   580     RepatchBuffer repatchBuffer(callLinkInfo->ownerCodeBlock.get());

   581 #if USE(JSVALUE32_64)

   582     repatchBuffer.repatch(callLinkInfo->hotPathBegin, 0);

   583 #else

   584     repatchBuffer.repatch(callLinkInfo->hotPathBegin, JSValue::encode(JSValue()));

   585 #endif

   586 }

   587 

   588 void JIT::linkCall(JSFunction* callee, CodeBlock* callerCodeBlock, CodeBlock* calleeCodeBlock, JITCode& code, CallLinkInfo* callLinkInfo, int callerArgCount, JSGlobalData* globalData)

   589 {

   590     RepatchBuffer repatchBuffer(callerCodeBlock);

   591 

   592     // Currently we only link calls with the exact number of arguments.

   593     // If this is a native call calleeCodeBlock is null so the number of parameters is unimportant

   594     if (!calleeCodeBlock || (callerArgCount == calleeCodeBlock->m_numParameters)) {

   595         ASSERT(!callLinkInfo->isLinked());

   596     

   597         if (calleeCodeBlock)

   598             calleeCodeBlock->addCaller(callLinkInfo);

   599     

   600         repatchBuffer.repatch(callLinkInfo->hotPathBegin, callee);

   601         repatchBuffer.relink(callLinkInfo->hotPathOther, code.addressForCall());

   602     }

   603 

   604     // patch the call so we do not continue to try to link.

   605     repatchBuffer.relink(callLinkInfo->callReturnLocation, globalData->jitStubs.ctiVirtualCall());

   606 }

   607 #endif // ENABLE(JIT_OPTIMIZE_CALL)

   608 

   609 } // namespace JSC

   610 

   611 #endif // ENABLE(JIT)