jit/JITPropertyAccess32_64.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
  28 #if ENABLE(JIT)
  29 #if USE(JSVALUE32_64)
  30 #include "JIT.h"
  31
  32 #include "CodeBlock.h"
  33 #include "GCAwareJITStubRoutine.h"
  34 #include "Interpreter.h"
  35 #include "JITInlines.h"
  36 #include "JITStubCall.h"
  37 #include "JSArray.h"
  38 #include "JSFunction.h"
  39 #include "JSPropertyNameIterator.h"
  40 #include "JSVariableObject.h"
  41 #include "LinkBuffer.h"
  42 #include "RepatchBuffer.h"
  43 #include "ResultType.h"
  44 #include "SamplingTool.h"
  45 #include <wtf/StringPrintStream.h>
  46
  47 #ifndef NDEBUG
  48 #include <stdio.h>
  49 #endif
  50
  51 using namespace std;
  52
  53 namespace JSC {
  54
  55 void JIT::emit_op_put_by_index(Instruction* currentInstruction)
  56 {
  57     unsigned base = currentInstruction[1].u.operand;
  58     unsigned property = currentInstruction[2].u.operand;
  59     unsigned value = currentInstruction[3].u.operand;
  60
  61     JITStubCall stubCall(this, cti_op_put_by_index);
  62     stubCall.addArgument(base);
  63     stubCall.addArgument(TrustedImm32(property));
  64     stubCall.addArgument(value);
  65     stubCall.call();
  66 }
  67
  68 void JIT::emit_op_put_getter_setter(Instruction* currentInstruction)
  69 {
  70     unsigned base = currentInstruction[1].u.operand;
  71     unsigned property = currentInstruction[2].u.operand;
  72     unsigned getter = currentInstruction[3].u.operand;
  73     unsigned setter = currentInstruction[4].u.operand;
  74
  75     JITStubCall stubCall(this, cti_op_put_getter_setter);
  76     stubCall.addArgument(base);
  77     stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(property)));
  78     stubCall.addArgument(getter);
  79     stubCall.addArgument(setter);
  80     stubCall.call();
  81 }
  82
  83 void JIT::emit_op_del_by_id(Instruction* currentInstruction)
  84 {
  85     unsigned dst = currentInstruction[1].u.operand;
  86     unsigned base = currentInstruction[2].u.operand;
  87     unsigned property = currentInstruction[3].u.operand;
  88
  89     JITStubCall stubCall(this, cti_op_del_by_id);
  90     stubCall.addArgument(base);
  91     stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(property)));
  92     stubCall.call(dst);
  93 }
  94
  95 JIT::CodeRef JIT::stringGetByValStubGenerator(VM* vm)
  96 {
  97     JSInterfaceJIT jit;
  98     JumpList failures;
  99     failures.append(jit.branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(vm->stringStructure.get())));
 100
 101     // Load string length to regT1, and start the process of loading the data pointer into regT0
 102     jit.load32(Address(regT0, ThunkHelpers::jsStringLengthOffset()), regT1);
 103     jit.loadPtr(Address(regT0, ThunkHelpers::jsStringValueOffset()), regT0);
 104     failures.append(jit.branchTest32(Zero, regT0));
 105
 106     // Do an unsigned compare to simultaneously filter negative indices as well as indices that are too large
 107     failures.append(jit.branch32(AboveOrEqual, regT2, regT1));
 108
 109     // Load the character
 110     JumpList is16Bit;
 111     JumpList cont8Bit;
 112     // Load the string flags
 113     jit.loadPtr(Address(regT0, StringImpl::flagsOffset()), regT1);
 114     jit.loadPtr(Address(regT0, StringImpl::dataOffset()), regT0);
 115     is16Bit.append(jit.branchTest32(Zero, regT1, TrustedImm32(StringImpl::flagIs8Bit())));
 116     jit.load8(BaseIndex(regT0, regT2, TimesOne, 0), regT0);
 117     cont8Bit.append(jit.jump());
 118     is16Bit.link(&jit);
 119     jit.load16(BaseIndex(regT0, regT2, TimesTwo, 0), regT0);
 120
 121     cont8Bit.link(&jit);
 122
 123     failures.append(jit.branch32(AboveOrEqual, regT0, TrustedImm32(0x100)));
 124     jit.move(TrustedImmPtr(vm->smallStrings.singleCharacterStrings()), regT1);
 125     jit.loadPtr(BaseIndex(regT1, regT0, ScalePtr, 0), regT0);
 126     jit.move(TrustedImm32(JSValue::CellTag), regT1); // We null check regT0 on return so this is safe
 127     jit.ret();
 128
 129     failures.link(&jit);
 130     jit.move(TrustedImm32(0), regT0);
 131     jit.ret();
 132
 133     LinkBuffer patchBuffer(*vm, &jit, GLOBAL_THUNK_ID);
 134     return FINALIZE_CODE(patchBuffer, ("String get_by_val stub"));
 135 }
 136
 137 void JIT::emit_op_get_by_val(Instruction* currentInstruction)
 138 {
 139     unsigned dst = currentInstruction[1].u.operand;
 140     unsigned base = currentInstruction[2].u.operand;
 141     unsigned property = currentInstruction[3].u.operand;
 142     ArrayProfile* profile = currentInstruction[4].u.arrayProfile;
 143
 144     emitLoad2(base, regT1, regT0, property, regT3, regT2);
 145
 146     addSlowCase(branch32(NotEqual, regT3, TrustedImm32(JSValue::Int32Tag)));
 147     emitJumpSlowCaseIfNotJSCell(base, regT1);
 148     loadPtr(Address(regT0, JSCell::structureOffset()), regT1);
 149     emitArrayProfilingSite(regT1, regT3, profile);
 150     and32(TrustedImm32(IndexingShapeMask), regT1);
 151
 152     PatchableJump badType;
 153     JumpList slowCases;
 154
 155     JITArrayMode mode = chooseArrayMode(profile);
 156     switch (mode) {
 157     case JITInt32:
 158         slowCases = emitInt32GetByVal(currentInstruction, badType);
 159         break;
 160     case JITDouble:
 161         slowCases = emitDoubleGetByVal(currentInstruction, badType);
 162         break;
 163     case JITContiguous:
 164         slowCases = emitContiguousGetByVal(currentInstruction, badType);
 165         break;
 166     case JITArrayStorage:
 167         slowCases = emitArrayStorageGetByVal(currentInstruction, badType);
 168         break;
 169     default:
 170         CRASH();
 171     }
 172
 173     addSlowCase(badType);
 174     addSlowCase(slowCases);
 175
 176     Label done = label();
 177
 178 #if !ASSERT_DISABLED
 179     Jump resultOK = branch32(NotEqual, regT1, TrustedImm32(JSValue::EmptyValueTag));
 180     breakpoint();
 181     resultOK.link(this);
 182 #endif
 183
 184     emitValueProfilingSite();
 185     emitStore(dst, regT1, regT0);
 186     map(m_bytecodeOffset + OPCODE_LENGTH(op_get_by_val), dst, regT1, regT0);
 187
 188     m_byValCompilationInfo.append(ByValCompilationInfo(m_bytecodeOffset, badType, mode, done));
 189 }
 190
 191 JIT::JumpList JIT::emitContiguousGetByVal(Instruction*, PatchableJump& badType, IndexingType expectedShape)
 192 {
 193     JumpList slowCases;
 194
 195     badType = patchableBranch32(NotEqual, regT1, TrustedImm32(expectedShape));
 196
 197     loadPtr(Address(regT0, JSObject::butterflyOffset()), regT3);
 198     slowCases.append(branch32(AboveOrEqual, regT2, Address(regT3, Butterfly::offsetOfPublicLength())));
 199
 200     load32(BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1); // tag
 201     load32(BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0); // payload
 202     slowCases.append(branch32(Equal, regT1, TrustedImm32(JSValue::EmptyValueTag)));
 203
 204     return slowCases;
 205 }
 206
 207 JIT::JumpList JIT::emitDoubleGetByVal(Instruction*, PatchableJump& badType)
 208 {
 209     JumpList slowCases;
 210
 211     badType = patchableBranch32(NotEqual, regT1, TrustedImm32(DoubleShape));
 212
 213     loadPtr(Address(regT0, JSObject::butterflyOffset()), regT3);
 214     slowCases.append(branch32(AboveOrEqual, regT2, Address(regT3, Butterfly::offsetOfPublicLength())));
 215
 216     loadDouble(BaseIndex(regT3, regT2, TimesEight), fpRegT0);
 217     slowCases.append(branchDouble(DoubleNotEqualOrUnordered, fpRegT0, fpRegT0));
 218     moveDoubleToInts(fpRegT0, regT0, regT1);
 219
 220     return slowCases;
 221 }
 222
 223 JIT::JumpList JIT::emitArrayStorageGetByVal(Instruction*, PatchableJump& badType)
 224 {
 225     JumpList slowCases;
 226
 227     add32(TrustedImm32(-ArrayStorageShape), regT1, regT3);
 228     badType = patchableBranch32(Above, regT3, TrustedImm32(SlowPutArrayStorageShape - ArrayStorageShape));
 229
 230     loadPtr(Address(regT0, JSObject::butterflyOffset()), regT3);
 231     slowCases.append(branch32(AboveOrEqual, regT2, Address(regT3, ArrayStorage::vectorLengthOffset())));
 232
 233     load32(BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(ArrayStorage, m_vector[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1); // tag
 234     load32(BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(ArrayStorage, m_vector[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0); // payload
 235     slowCases.append(branch32(Equal, regT1, TrustedImm32(JSValue::EmptyValueTag)));
 236
 237     return slowCases;
 238 }
 239
 240 void JIT::emitSlow_op_get_by_val(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 241 {
 242     unsigned dst = currentInstruction[1].u.operand;
 243     unsigned base = currentInstruction[2].u.operand;
 244     unsigned property = currentInstruction[3].u.operand;
 245     ArrayProfile* profile = currentInstruction[4].u.arrayProfile;
 246
 247     linkSlowCase(iter); // property int32 check
 248     linkSlowCaseIfNotJSCell(iter, base); // base cell check
 249
 250     Jump nonCell = jump();
 251     linkSlowCase(iter); // base array check
 252     Jump notString = branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get()));
 253     emitNakedCall(m_vm->getCTIStub(stringGetByValStubGenerator).code());
 254     Jump failed = branchTestPtr(Zero, regT0);
 255     emitStore(dst, regT1, regT0);
 256     emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_get_by_val));
 257     failed.link(this);
 258     notString.link(this);
 259     nonCell.link(this);
 260
 261     Jump skipProfiling = jump();
 262
 263     linkSlowCase(iter); // vector length check
 264     linkSlowCase(iter); // empty value
 265
 266     emitArrayProfileOutOfBoundsSpecialCase(profile);
 267
 268     skipProfiling.link(this);
 269
 270     Label slowPath = label();
 271
 272     JITStubCall stubCall(this, cti_op_get_by_val);
 273     stubCall.addArgument(base);
 274     stubCall.addArgument(property);
 275     Call call = stubCall.call(dst);
 276
 277     m_byValCompilationInfo[m_byValInstructionIndex].slowPathTarget = slowPath;
 278     m_byValCompilationInfo[m_byValInstructionIndex].returnAddress = call;
 279     m_byValInstructionIndex++;
 280
 281     emitValueProfilingSite();
 282 }
 283
 284 void JIT::emit_op_put_by_val(Instruction* currentInstruction)
 285 {
 286     unsigned base = currentInstruction[1].u.operand;
 287     unsigned property = currentInstruction[2].u.operand;
 288     ArrayProfile* profile = currentInstruction[4].u.arrayProfile;
 289
 290     emitLoad2(base, regT1, regT0, property, regT3, regT2);
 291
 292     addSlowCase(branch32(NotEqual, regT3, TrustedImm32(JSValue::Int32Tag)));
 293     emitJumpSlowCaseIfNotJSCell(base, regT1);
 294     loadPtr(Address(regT0, JSCell::structureOffset()), regT1);
 295     emitArrayProfilingSite(regT1, regT3, profile);
 296     and32(TrustedImm32(IndexingShapeMask), regT1);
 297
 298     PatchableJump badType;
 299     JumpList slowCases;
 300
 301     JITArrayMode mode = chooseArrayMode(profile);
 302     switch (mode) {
 303     case JITInt32:
 304         slowCases = emitInt32PutByVal(currentInstruction, badType);
 305         break;
 306     case JITDouble:
 307         slowCases = emitDoublePutByVal(currentInstruction, badType);
 308         break;
 309     case JITContiguous:
 310         slowCases = emitContiguousPutByVal(currentInstruction, badType);
 311         break;
 312     case JITArrayStorage:
 313         slowCases = emitArrayStoragePutByVal(currentInstruction, badType);
 314         break;
 315     default:
 316         CRASH();
 317         break;
 318     }
 319
 320     addSlowCase(badType);
 321     addSlowCase(slowCases);
 322
 323     Label done = label();
 324
 325     m_byValCompilationInfo.append(ByValCompilationInfo(m_bytecodeOffset, badType, mode, done));
 326 }
 327
 328 JIT::JumpList JIT::emitGenericContiguousPutByVal(Instruction* currentInstruction, PatchableJump& badType, IndexingType indexingShape)
 329 {
 330     unsigned value = currentInstruction[3].u.operand;
 331     ArrayProfile* profile = currentInstruction[4].u.arrayProfile;
 332
 333     JumpList slowCases;
 334
 335     badType = patchableBranch32(NotEqual, regT1, TrustedImm32(ContiguousShape));
 336
 337     loadPtr(Address(regT0, JSObject::butterflyOffset()), regT3);
 338     Jump outOfBounds = branch32(AboveOrEqual, regT2, Address(regT3, Butterfly::offsetOfPublicLength()));
 339
 340     Label storeResult = label();
 341     emitLoad(value, regT1, regT0);
 342     switch (indexingShape) {
 343     case Int32Shape:
 344         slowCases.append(branch32(NotEqual, regT1, TrustedImm32(JSValue::Int32Tag)));
 345         // Fall through.
 346     case ContiguousShape:
 347         store32(regT0, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload)));
 348         store32(regT1, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag)));
 349         break;
 350     case DoubleShape: {
 351         Jump notInt = branch32(NotEqual, regT1, TrustedImm32(JSValue::Int32Tag));
 352         convertInt32ToDouble(regT0, fpRegT0);
 353         Jump ready = jump();
 354         notInt.link(this);
 355         moveIntsToDouble(regT0, regT1, fpRegT0, fpRegT1);
 356         slowCases.append(branchDouble(DoubleNotEqualOrUnordered, fpRegT0, fpRegT0));
 357         ready.link(this);
 358         storeDouble(fpRegT0, BaseIndex(regT3, regT2, TimesEight));
 359         break;
 360     }
 361     default:
 362         CRASH();
 363         break;
 364     }
 365
 366     Jump done = jump();
 367
 368     outOfBounds.link(this);
 369     slowCases.append(branch32(AboveOrEqual, regT2, Address(regT3, Butterfly::offsetOfVectorLength())));
 370
 371     emitArrayProfileStoreToHoleSpecialCase(profile);
 372
 373     add32(TrustedImm32(1), regT2, regT1);
 374     store32(regT1, Address(regT3, Butterfly::offsetOfPublicLength()));
 375     jump().linkTo(storeResult, this);
 376
 377     done.link(this);
 378
 379     emitWriteBarrier(regT0, regT1, regT1, regT3, UnconditionalWriteBarrier, WriteBarrierForPropertyAccess);
 380
 381     return slowCases;
 382 }
 383
 384 JIT::JumpList JIT::emitArrayStoragePutByVal(Instruction* currentInstruction, PatchableJump& badType)
 385 {
 386     unsigned value = currentInstruction[3].u.operand;
 387     ArrayProfile* profile = currentInstruction[4].u.arrayProfile;
 388
 389     JumpList slowCases;
 390
 391     badType = patchableBranch32(NotEqual, regT1, TrustedImm32(ArrayStorageShape));
 392
 393     loadPtr(Address(regT0, JSObject::butterflyOffset()), regT3);
 394     slowCases.append(branch32(AboveOrEqual, regT2, Address(regT3, ArrayStorage::vectorLengthOffset())));
 395
 396     Jump empty = branch32(Equal, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(ArrayStorage, m_vector[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), TrustedImm32(JSValue::EmptyValueTag));
 397
 398     Label storeResult(this);
 399     emitLoad(value, regT1, regT0);
 400     store32(regT0, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(ArrayStorage, m_vector[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.payload))); // payload
 401     store32(regT1, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(ArrayStorage, m_vector[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.tag))); // tag
 402     Jump end = jump();
 403
 404     empty.link(this);
 405     emitArrayProfileStoreToHoleSpecialCase(profile);
 406     add32(TrustedImm32(1), Address(regT3, OBJECT_OFFSETOF(ArrayStorage, m_numValuesInVector)));
 407     branch32(Below, regT2, Address(regT3, ArrayStorage::lengthOffset())).linkTo(storeResult, this);
 408
 409     add32(TrustedImm32(1), regT2, regT0);
 410     store32(regT0, Address(regT3, ArrayStorage::lengthOffset()));
 411     jump().linkTo(storeResult, this);
 412
 413     end.link(this);
 414
 415     emitWriteBarrier(regT0, regT1, regT1, regT3, UnconditionalWriteBarrier, WriteBarrierForPropertyAccess);
 416
 417     return slowCases;
 418 }
 419
 420 void JIT::emitSlow_op_put_by_val(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 421 {
 422     unsigned base = currentInstruction[1].u.operand;
 423     unsigned property = currentInstruction[2].u.operand;
 424     unsigned value = currentInstruction[3].u.operand;
 425     ArrayProfile* profile = currentInstruction[4].u.arrayProfile;
 426
 427     linkSlowCase(iter); // property int32 check
 428     linkSlowCaseIfNotJSCell(iter, base); // base cell check
 429     linkSlowCase(iter); // base not array check
 430
 431     JITArrayMode mode = chooseArrayMode(profile);
 432     switch (mode) {
 433     case JITInt32:
 434     case JITDouble:
 435         linkSlowCase(iter); // value type check
 436         break;
 437     default:
 438         break;
 439     }
 440
 441     Jump skipProfiling = jump();
 442     linkSlowCase(iter); // out of bounds
 443     emitArrayProfileOutOfBoundsSpecialCase(profile);
 444     skipProfiling.link(this);
 445
 446     Label slowPath = label();
 447
 448     JITStubCall stubPutByValCall(this, cti_op_put_by_val);
 449     stubPutByValCall.addArgument(base);
 450     stubPutByValCall.addArgument(property);
 451     stubPutByValCall.addArgument(value);
 452     Call call = stubPutByValCall.call();
 453
 454     m_byValCompilationInfo[m_byValInstructionIndex].slowPathTarget = slowPath;
 455     m_byValCompilationInfo[m_byValInstructionIndex].returnAddress = call;
 456     m_byValInstructionIndex++;
 457 }
 458
 459 void JIT::emit_op_get_by_id(Instruction* currentInstruction)
 460 {
 461     int dst = currentInstruction[1].u.operand;
 462     int base = currentInstruction[2].u.operand;
 463     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 464
 465     emitLoad(base, regT1, regT0);
 466     emitJumpSlowCaseIfNotJSCell(base, regT1);
 467     compileGetByIdHotPath(ident);
 468     emitValueProfilingSite();
 469     emitStore(dst, regT1, regT0);
 470     map(m_bytecodeOffset + OPCODE_LENGTH(op_get_by_id), dst, regT1, regT0);
 471 }
 472
 473 void JIT::compileGetByIdHotPath(Identifier* ident)
 474 {
 475     // As for put_by_id, get_by_id requires the offset of the Structure and the offset of the access to be patched.
 476     // Additionally, for get_by_id we need patch the offset of the branch to the slow case (we patch this to jump
 477     // to array-length / prototype access tranpolines, and finally we also the the property-map access offset as a label
 478     // to jump back to if one of these trampolies finds a match.
 479
 480     if (*ident == m_vm->propertyNames->length && shouldEmitProfiling()) {
 481         loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
 482         emitArrayProfilingSiteForBytecodeIndex(regT2, regT3, m_bytecodeOffset);
 483     }
 484
 485     BEGIN_UNINTERRUPTED_SEQUENCE(sequenceGetByIdHotPath);
 486
 487     Label hotPathBegin(this);
 488
 489     DataLabelPtr structureToCompare;
 490     PatchableJump structureCheck = patchableBranchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure)));
 491     addSlowCase(structureCheck);
 492
 493     ConvertibleLoadLabel propertyStorageLoad = convertibleLoadPtr(Address(regT0, JSObject::butterflyOffset()), regT2);
 494     DataLabelCompact displacementLabel1 = loadPtrWithCompactAddressOffsetPatch(Address(regT2, patchGetByIdDefaultOffset), regT0); // payload
 495     DataLabelCompact displacementLabel2 = loadPtrWithCompactAddressOffsetPatch(Address(regT2, patchGetByIdDefaultOffset), regT1); // tag
 496
 497     Label putResult(this);
 498
 499     END_UNINTERRUPTED_SEQUENCE(sequenceGetByIdHotPath);
 500
 501     m_propertyAccessCompilationInfo.append(PropertyStubCompilationInfo(PropertyStubGetById, m_bytecodeOffset, hotPathBegin, structureToCompare, structureCheck, propertyStorageLoad, displacementLabel1, displacementLabel2, putResult));
 502 }
 503
 504 void JIT::emitSlow_op_get_by_id(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 505 {
 506     int dst = currentInstruction[1].u.operand;
 507     int base = currentInstruction[2].u.operand;
 508     int ident = currentInstruction[3].u.operand;
 509
 510     compileGetByIdSlowCase(dst, base, &(m_codeBlock->identifier(ident)), iter);
 511     emitValueProfilingSite();
 512 }
 513
 514 void JIT::compileGetByIdSlowCase(int dst, int base, Identifier* ident, Vector<SlowCaseEntry>::iterator& iter)
 515 {
 516     // As for the hot path of get_by_id, above, we ensure that we can use an architecture specific offset
 517     // so that we only need track one pointer into the slow case code - we track a pointer to the location
 518     // of the call (which we can use to look up the patch information), but should a array-length or
 519     // prototype access trampoline fail we want to bail out back to here.  To do so we can subtract back
 520     // the distance from the call to the head of the slow case.
 521     linkSlowCaseIfNotJSCell(iter, base);
 522     linkSlowCase(iter);
 523
 524     BEGIN_UNINTERRUPTED_SEQUENCE(sequenceGetByIdSlowCase);
 525
 526     Label coldPathBegin(this);
 527     JITStubCall stubCall(this, cti_op_get_by_id);
 528     stubCall.addArgument(regT1, regT0);
 529     stubCall.addArgument(TrustedImmPtr(ident));
 530     Call call = stubCall.call(dst);
 531
 532     END_UNINTERRUPTED_SEQUENCE_FOR_PUT(sequenceGetByIdSlowCase, dst);
 533
 534     // Track the location of the call; this will be used to recover patch information.
 535     m_propertyAccessCompilationInfo[m_propertyAccessInstructionIndex++].slowCaseInfo(PropertyStubGetById, coldPathBegin, call);
 536 }
 537
 538 void JIT::emit_op_put_by_id(Instruction* currentInstruction)
 539 {
 540     // In order to be able to patch both the Structure, and the object offset, we store one pointer,
 541     // to just after the arguments have been loaded into registers 'hotPathBegin', and we generate code
 542     // such that the Structure & offset are always at the same distance from this.
 543
 544     int base = currentInstruction[1].u.operand;
 545     int value = currentInstruction[3].u.operand;
 546
 547     emitLoad2(base, regT1, regT0, value, regT3, regT2);
 548
 549     emitJumpSlowCaseIfNotJSCell(base, regT1);
 550
 551     BEGIN_UNINTERRUPTED_SEQUENCE(sequencePutById);
 552
 553     Label hotPathBegin(this);
 554
 555     // It is important that the following instruction plants a 32bit immediate, in order that it can be patched over.
 556     DataLabelPtr structureToCompare;
 557     addSlowCase(branchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure))));
 558
 559     ConvertibleLoadLabel propertyStorageLoad = convertibleLoadPtr(Address(regT0, JSObject::butterflyOffset()), regT1);
 560     DataLabel32 displacementLabel1 = storePtrWithAddressOffsetPatch(regT2, Address(regT1, patchPutByIdDefaultOffset)); // payload
 561     DataLabel32 displacementLabel2 = storePtrWithAddressOffsetPatch(regT3, Address(regT1, patchPutByIdDefaultOffset)); // tag
 562
 563     END_UNINTERRUPTED_SEQUENCE(sequencePutById);
 564
 565     emitWriteBarrier(regT0, regT2, regT1, regT2, ShouldFilterImmediates, WriteBarrierForPropertyAccess);
 566
 567     m_propertyAccessCompilationInfo.append(PropertyStubCompilationInfo(PropertyStubPutById, m_bytecodeOffset, hotPathBegin, structureToCompare, propertyStorageLoad, displacementLabel1, displacementLabel2));
 568 }
 569
 570 void JIT::emitSlow_op_put_by_id(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 571 {
 572     int base = currentInstruction[1].u.operand;
 573     int ident = currentInstruction[2].u.operand;
 574     int direct = currentInstruction[8].u.operand;
 575
 576     linkSlowCaseIfNotJSCell(iter, base);
 577     linkSlowCase(iter);
 578
 579     JITStubCall stubCall(this, direct ? cti_op_put_by_id_direct : cti_op_put_by_id);
 580     stubCall.addArgument(base);
 581     stubCall.addArgument(TrustedImmPtr(&(m_codeBlock->identifier(ident))));
 582     stubCall.addArgument(regT3, regT2);
 583     Call call = stubCall.call();
 584
 585     // Track the location of the call; this will be used to recover patch information.
 586     m_propertyAccessCompilationInfo[m_propertyAccessInstructionIndex++].slowCaseInfo(PropertyStubPutById, call);
 587 }
 588
 589 // Compile a store into an object's property storage.  May overwrite base.
 590 void JIT::compilePutDirectOffset(RegisterID base, RegisterID valueTag, RegisterID valuePayload, PropertyOffset cachedOffset)
 591 {
 592     if (isOutOfLineOffset(cachedOffset))
 593         loadPtr(Address(base, JSObject::butterflyOffset()), base);
 594     emitStore(indexRelativeToBase(cachedOffset), valueTag, valuePayload, base);
 595 }
 596
 597 // Compile a load from an object's property storage.  May overwrite base.
 598 void JIT::compileGetDirectOffset(RegisterID base, RegisterID resultTag, RegisterID resultPayload, PropertyOffset cachedOffset)
 599 {
 600     if (isInlineOffset(cachedOffset)) {
 601         emitLoad(indexRelativeToBase(cachedOffset), resultTag, resultPayload, base);
 602         return;
 603     }
 604
 605     RegisterID temp = resultPayload;
 606     loadPtr(Address(base, JSObject::butterflyOffset()), temp);
 607     emitLoad(indexRelativeToBase(cachedOffset), resultTag, resultPayload, temp);
 608 }
 609
 610 void JIT::compileGetDirectOffset(JSObject* base, RegisterID resultTag, RegisterID resultPayload, PropertyOffset cachedOffset)
 611 {
 612     if (isInlineOffset(cachedOffset)) {
 613         move(TrustedImmPtr(base->locationForOffset(cachedOffset)), resultTag);
 614         load32(Address(resultTag, OBJECT_OFFSETOF(JSValue, u.asBits.payload)), resultPayload);
 615         load32(Address(resultTag, OBJECT_OFFSETOF(JSValue, u.asBits.tag)), resultTag);
 616         return;
 617     }
 618
 619     loadPtr(base->butterflyAddress(), resultTag);
 620     load32(Address(resultTag, offsetInButterfly(cachedOffset) * sizeof(WriteBarrier<Unknown>) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), resultPayload);
 621     load32(Address(resultTag, offsetInButterfly(cachedOffset) * sizeof(WriteBarrier<Unknown>) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), resultTag);
 622 }
 623
 624 void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure* oldStructure, Structure* newStructure, PropertyOffset cachedOffset, StructureChain* chain, ReturnAddressPtr returnAddress, bool direct)
 625 {
 626     // The code below assumes that regT0 contains the basePayload and regT1 contains the baseTag. Restore them from the stack.
 627 #if CPU(MIPS) || CPU(SH4) || CPU(ARM)
 628     // For MIPS, we don't add sizeof(void*) to the stack offset.
 629     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
 630     // For MIPS, we don't add sizeof(void*) to the stack offset.
 631     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
 632 #else
 633     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + sizeof(void*) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
 634     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + sizeof(void*) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
 635 #endif
 636
 637     JumpList failureCases;
 638     failureCases.append(branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag)));
 639     failureCases.append(branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(oldStructure)));
 640     testPrototype(oldStructure->storedPrototype(), failureCases, stubInfo);
 641
 642     if (!direct) {
 643         // Verify that nothing in the prototype chain has a setter for this property.
 644         for (WriteBarrier<Structure>* it = chain->head(); *it; ++it)
 645             testPrototype((*it)->storedPrototype(), failureCases, stubInfo);
 646     }
 647
 648     // If we succeed in all of our checks, and the code was optimizable, then make sure we
 649     // decrement the rare case counter.
 650 #if ENABLE(VALUE_PROFILER)
 651     if (m_codeBlock->canCompileWithDFG() >= DFG::MayInline) {
 652         sub32(
 653             TrustedImm32(1),
 654             AbsoluteAddress(&m_codeBlock->rareCaseProfileForBytecodeOffset(stubInfo->bytecodeIndex)->m_counter));
 655     }
 656 #endif
 657
 658     // Reallocate property storage if needed.
 659     Call callTarget;
 660     bool willNeedStorageRealloc = oldStructure->outOfLineCapacity() != newStructure->outOfLineCapacity();
 661     if (willNeedStorageRealloc) {
 662         // This trampoline was called to like a JIT stub; before we can can call again we need to
 663         // remove the return address from the stack, to prevent the stack from becoming misaligned.
 664         preserveReturnAddressAfterCall(regT3);
 665
 666         JITStubCall stubCall(this, cti_op_put_by_id_transition_realloc);
 667         stubCall.skipArgument(); // base
 668         stubCall.skipArgument(); // ident
 669         stubCall.skipArgument(); // value
 670         stubCall.addArgument(TrustedImm32(oldStructure->outOfLineCapacity()));
 671         stubCall.addArgument(TrustedImmPtr(newStructure));
 672         stubCall.call(regT0);
 673
 674         restoreReturnAddressBeforeReturn(regT3);
 675
 676 #if CPU(MIPS) || CPU(SH4) || CPU(ARM)
 677         // For MIPS, we don't add sizeof(void*) to the stack offset.
 678         load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
 679         // For MIPS, we don't add sizeof(void*) to the stack offset.
 680         load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
 681 #else
 682         load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + sizeof(void*) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
 683         load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[0]) + sizeof(void*) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
 684 #endif
 685     }
 686
 687     emitWriteBarrier(regT0, regT1, regT1, regT3, UnconditionalWriteBarrier, WriteBarrierForPropertyAccess);
 688
 689     storePtr(TrustedImmPtr(newStructure), Address(regT0, JSCell::structureOffset()));
 690 #if CPU(MIPS) || CPU(SH4) || CPU(ARM)
 691     // For MIPS, we don't add sizeof(void*) to the stack offset.
 692     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[2]) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT3);
 693     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[2]) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT2);
 694 #else
 695     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[2]) + sizeof(void*) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT3);
 696     load32(Address(stackPointerRegister, OBJECT_OFFSETOF(JITStackFrame, args[2]) + sizeof(void*) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT2);
 697 #endif
 698     compilePutDirectOffset(regT0, regT2, regT3, cachedOffset);
 699
 700     ret();
 701
 702     ASSERT(!failureCases.empty());
 703     failureCases.link(this);
 704     restoreArgumentReferenceForTrampoline();
 705     Call failureCall = tailRecursiveCall();
 706
 707     LinkBuffer patchBuffer(*m_vm, this, m_codeBlock);
 708
 709     patchBuffer.link(failureCall, FunctionPtr(direct ? cti_op_put_by_id_direct_fail : cti_op_put_by_id_fail));
 710
 711     if (willNeedStorageRealloc) {
 712         ASSERT(m_calls.size() == 1);
 713         patchBuffer.link(m_calls[0].from, FunctionPtr(cti_op_put_by_id_transition_realloc));
 714     }
 715
 716     stubInfo->stubRoutine = createJITStubRoutine(
 717         FINALIZE_CODE(
 718             patchBuffer,
 719             ("Baseline put_by_id transition stub for %s, return point %p",
 720                 toCString(*m_codeBlock).data(), returnAddress.value())),
 721         *m_vm,
 722         m_codeBlock->ownerExecutable(),
 723         willNeedStorageRealloc,
 724         newStructure);
 725     RepatchBuffer repatchBuffer(m_codeBlock);
 726     repatchBuffer.relinkCallerToTrampoline(returnAddress, CodeLocationLabel(stubInfo->stubRoutine->code().code()));
 727 }
 728
 729 void JIT::patchGetByIdSelf(CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, PropertyOffset cachedOffset, ReturnAddressPtr returnAddress)
 730 {
 731     RepatchBuffer repatchBuffer(codeBlock);
 732
 733     // We don't want to patch more than once - in future go to cti_op_get_by_id_generic.
 734     // Should probably go to JITStubs::cti_op_get_by_id_fail, but that doesn't do anything interesting right now.
 735     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_self_fail));
 736
 737     // Patch the offset into the propoerty map to load from, then patch the Structure to look for.
 738     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.get.structureToCompare), structure);
 739     repatchBuffer.setLoadInstructionIsActive(stubInfo->hotPathBegin.convertibleLoadAtOffset(stubInfo->patch.baseline.u.get.propertyStorageLoad), isOutOfLineOffset(cachedOffset));
 740     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.get.displacementLabel1), offsetRelativeToPatchedStorage(cachedOffset) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)); // payload
 741     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.get.displacementLabel2), offsetRelativeToPatchedStorage(cachedOffset) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)); // tag
 742 }
 743
 744 void JIT::patchPutByIdReplace(CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, PropertyOffset cachedOffset, ReturnAddressPtr returnAddress, bool direct)
 745 {
 746     RepatchBuffer repatchBuffer(codeBlock);
 747
 748     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
 749     // Should probably go to cti_op_put_by_id_fail, but that doesn't do anything interesting right now.
 750     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(direct ? cti_op_put_by_id_direct_generic : cti_op_put_by_id_generic));
 751
 752     // Patch the offset into the propoerty map to load from, then patch the Structure to look for.
 753     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.put.structureToCompare), structure);
 754     repatchBuffer.setLoadInstructionIsActive(stubInfo->hotPathBegin.convertibleLoadAtOffset(stubInfo->patch.baseline.u.put.propertyStorageLoad), isOutOfLineOffset(cachedOffset));
 755     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(stubInfo->patch.baseline.u.put.displacementLabel1), offsetRelativeToPatchedStorage(cachedOffset) + OBJECT_OFFSETOF(JSValue, u.asBits.payload)); // payload
 756     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(stubInfo->patch.baseline.u.put.displacementLabel2), offsetRelativeToPatchedStorage(cachedOffset) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)); // tag
 757 }
 758
 759 void JIT::privateCompilePatchGetArrayLength(ReturnAddressPtr returnAddress)
 760 {
 761     StructureStubInfo* stubInfo = &m_codeBlock->getStubInfo(returnAddress);
 762
 763     // regT0 holds a JSCell*
 764
 765     // Check for array
 766     loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
 767     Jump failureCases1 = branchTest32(Zero, regT2, TrustedImm32(IsArray));
 768     Jump failureCases2 = branchTest32(Zero, regT2, TrustedImm32(IndexingShapeMask));
 769
 770     // Checks out okay! - get the length from the storage
 771     loadPtr(Address(regT0, JSArray::butterflyOffset()), regT2);
 772     load32(Address(regT2, ArrayStorage::lengthOffset()), regT2);
 773
 774     Jump failureCases3 = branch32(Above, regT2, TrustedImm32(INT_MAX));
 775     move(regT2, regT0);
 776     move(TrustedImm32(JSValue::Int32Tag), regT1);
 777     Jump success = jump();
 778
 779     LinkBuffer patchBuffer(*m_vm, this, m_codeBlock);
 780
 781     // Use the patch information to link the failure cases back to the original slow case routine.
 782     CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin);
 783     patchBuffer.link(failureCases1, slowCaseBegin);
 784     patchBuffer.link(failureCases2, slowCaseBegin);
 785     patchBuffer.link(failureCases3, slowCaseBegin);
 786
 787     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 788     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 789
 790     // Track the stub we have created so that it will be deleted later.
 791     stubInfo->stubRoutine = FINALIZE_CODE_FOR_STUB(
 792         patchBuffer,
 793         ("Baseline get_by_id array length stub for %s, return point %p",
 794             toCString(*m_codeBlock).data(), stubInfo->hotPathBegin.labelAtOffset(
 795                 stubInfo->patch.baseline.u.get.putResult).executableAddress()));
 796
 797     // Finally patch the jump to slow case back in the hot path to jump here instead.
 798     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
 799     RepatchBuffer repatchBuffer(m_codeBlock);
 800     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubInfo->stubRoutine->code().code()));
 801
 802     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
 803     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_array_fail));
 804 }
 805
 806 void JIT::privateCompileGetByIdProto(StructureStubInfo* stubInfo, Structure* structure, Structure* prototypeStructure, const Identifier& ident, const PropertySlot& slot, PropertyOffset cachedOffset, ReturnAddressPtr returnAddress, CallFrame* callFrame)
 807 {
 808     // regT0 holds a JSCell*
 809
 810     // The prototype object definitely exists (if this stub exists the CodeBlock is referencing a Structure that is
 811     // referencing the prototype object - let's speculatively load it's table nice and early!)
 812     JSObject* protoObject = asObject(structure->prototypeForLookup(callFrame));
 813
 814     Jump failureCases1 = checkStructure(regT0, structure);
 815
 816     // Check the prototype object's Structure had not changed.
 817     Jump failureCases2 = addStructureTransitionCheck(protoObject, prototypeStructure, stubInfo, regT3);
 818
 819     bool needsStubLink = false;
 820     // Checks out okay!
 821     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 822         needsStubLink = true;
 823         compileGetDirectOffset(protoObject, regT2, regT1, cachedOffset);
 824         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 825         stubCall.addArgument(regT1);
 826         stubCall.addArgument(regT0);
 827         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 828         stubCall.call();
 829     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 830         needsStubLink = true;
 831         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 832         stubCall.addArgument(TrustedImmPtr(protoObject));
 833         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 834         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 835         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 836         stubCall.call();
 837     } else
 838         compileGetDirectOffset(protoObject, regT1, regT0, cachedOffset);
 839
 840     Jump success = jump();
 841
 842     LinkBuffer patchBuffer(*m_vm, this, m_codeBlock);
 843
 844     // Use the patch information to link the failure cases back to the original slow case routine.
 845     CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin);
 846     patchBuffer.link(failureCases1, slowCaseBegin);
 847     if (failureCases2.isSet())
 848         patchBuffer.link(failureCases2, slowCaseBegin);
 849
 850     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 851     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 852
 853     if (needsStubLink) {
 854         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 855             if (iter->to)
 856                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 857         }
 858     }
 859
 860     // Track the stub we have created so that it will be deleted later.
 861     stubInfo->stubRoutine = createJITStubRoutine(
 862         FINALIZE_CODE(
 863             patchBuffer,
 864             ("Baseline get_by_id proto stub for %s, return point %p",
 865                 toCString(*m_codeBlock).data(), stubInfo->hotPathBegin.labelAtOffset(
 866                     stubInfo->patch.baseline.u.get.putResult).executableAddress())),
 867         *m_vm,
 868         m_codeBlock->ownerExecutable(),
 869         needsStubLink);
 870
 871     // Finally patch the jump to slow case back in the hot path to jump here instead.
 872     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
 873     RepatchBuffer repatchBuffer(m_codeBlock);
 874     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubInfo->stubRoutine->code().code()));
 875
 876     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
 877     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_proto_list));
 878 }
 879
 880
 881 void JIT::privateCompileGetByIdSelfList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* polymorphicStructures, int currentIndex, Structure* structure, const Identifier& ident, const PropertySlot& slot, PropertyOffset cachedOffset)
 882 {
 883     // regT0 holds a JSCell*
 884     Jump failureCase = checkStructure(regT0, structure);
 885     bool needsStubLink = false;
 886     bool isDirect = false;
 887     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 888         needsStubLink = true;
 889         compileGetDirectOffset(regT0, regT2, regT1, cachedOffset);
 890         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 891         stubCall.addArgument(regT1);
 892         stubCall.addArgument(regT0);
 893         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 894         stubCall.call();
 895     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 896         needsStubLink = true;
 897         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 898         stubCall.addArgument(regT0);
 899         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 900         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 901         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 902         stubCall.call();
 903     } else {
 904         isDirect = true;
 905         compileGetDirectOffset(regT0, regT1, regT0, cachedOffset);
 906     }
 907
 908     Jump success = jump();
 909
 910     LinkBuffer patchBuffer(*m_vm, this, m_codeBlock);
 911     if (needsStubLink) {
 912         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 913             if (iter->to)
 914                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 915         }
 916     }
 917     // Use the patch information to link the failure cases back to the original slow case routine.
 918     CodeLocationLabel lastProtoBegin = CodeLocationLabel(JITStubRoutine::asCodePtr(polymorphicStructures->list[currentIndex - 1].stubRoutine));
 919     if (!lastProtoBegin)
 920         lastProtoBegin = stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin);
 921
 922     patchBuffer.link(failureCase, lastProtoBegin);
 923
 924     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 925     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 926
 927     RefPtr<JITStubRoutine> stubRoutine = createJITStubRoutine(
 928         FINALIZE_CODE(
 929             patchBuffer,
 930             ("Baseline get_by_id self list stub for %s, return point %p",
 931                 toCString(*m_codeBlock).data(), stubInfo->hotPathBegin.labelAtOffset(
 932                     stubInfo->patch.baseline.u.get.putResult).executableAddress())),
 933         *m_vm,
 934         m_codeBlock->ownerExecutable(),
 935         needsStubLink);
 936
 937     polymorphicStructures->list[currentIndex].set(*m_vm, m_codeBlock->ownerExecutable(), stubRoutine, structure, isDirect);
 938
 939     // Finally patch the jump to slow case back in the hot path to jump here instead.
 940     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
 941     RepatchBuffer repatchBuffer(m_codeBlock);
 942     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine->code().code()));
 943 }
 944
 945 void JIT::privateCompileGetByIdProtoList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructures, int currentIndex, Structure* structure, Structure* prototypeStructure, const Identifier& ident, const PropertySlot& slot, PropertyOffset cachedOffset, CallFrame* callFrame)
 946 {
 947     // regT0 holds a JSCell*
 948
 949     // The prototype object definitely exists (if this stub exists the CodeBlock is referencing a Structure that is
 950     // referencing the prototype object - let's speculatively load it's table nice and early!)
 951     JSObject* protoObject = asObject(structure->prototypeForLookup(callFrame));
 952
 953     // Check eax is an object of the right Structure.
 954     Jump failureCases1 = checkStructure(regT0, structure);
 955
 956     // Check the prototype object's Structure had not changed.
 957     Jump failureCases2 = addStructureTransitionCheck(protoObject, prototypeStructure, stubInfo, regT3);
 958
 959     bool needsStubLink = false;
 960     bool isDirect = false;
 961     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 962         needsStubLink = true;
 963         compileGetDirectOffset(protoObject, regT2, regT1, cachedOffset);
 964         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 965         stubCall.addArgument(regT1);
 966         stubCall.addArgument(regT0);
 967         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 968         stubCall.call();
 969     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 970         needsStubLink = true;
 971         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 972         stubCall.addArgument(TrustedImmPtr(protoObject));
 973         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 974         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 975         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 976         stubCall.call();
 977     } else {
 978         isDirect = true;
 979         compileGetDirectOffset(protoObject, regT1, regT0, cachedOffset);
 980     }
 981
 982     Jump success = jump();
 983
 984     LinkBuffer patchBuffer(*m_vm, this, m_codeBlock);
 985     if (needsStubLink) {
 986         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 987             if (iter->to)
 988                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 989         }
 990     }
 991     // Use the patch information to link the failure cases back to the original slow case routine.
 992     CodeLocationLabel lastProtoBegin = CodeLocationLabel(JITStubRoutine::asCodePtr(prototypeStructures->list[currentIndex - 1].stubRoutine));
 993     patchBuffer.link(failureCases1, lastProtoBegin);
 994     if (failureCases2.isSet())
 995         patchBuffer.link(failureCases2, lastProtoBegin);
 996
 997     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 998     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 999
1000     RefPtr<JITStubRoutine> stubRoutine = createJITStubRoutine(
1001         FINALIZE_CODE(
1002             patchBuffer,
1003             ("Baseline get_by_id proto list stub for %s, return point %p",
1004                 toCString(*m_codeBlock).data(), stubInfo->hotPathBegin.labelAtOffset(
1005                     stubInfo->patch.baseline.u.get.putResult).executableAddress())),
1006         *m_vm,
1007         m_codeBlock->ownerExecutable(),
1008         needsStubLink);
1009
1010     prototypeStructures->list[currentIndex].set(callFrame->vm(), m_codeBlock->ownerExecutable(), stubRoutine, structure, prototypeStructure, isDirect);
1011
1012     // Finally patch the jump to slow case back in the hot path to jump here instead.
1013     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
1014     RepatchBuffer repatchBuffer(m_codeBlock);
1015     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine->code().code()));
1016 }
1017
1018 void JIT::privateCompileGetByIdChainList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructures, int currentIndex, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, PropertyOffset cachedOffset, CallFrame* callFrame)
1019 {
1020     // regT0 holds a JSCell*
1021     ASSERT(count);
1022
1023     JumpList bucketsOfFail;
1024
1025     // Check eax is an object of the right Structure.
1026     bucketsOfFail.append(checkStructure(regT0, structure));
1027
1028     Structure* currStructure = structure;
1029     WriteBarrier<Structure>* it = chain->head();
1030     JSObject* protoObject = 0;
1031     for (unsigned i = 0; i < count; ++i, ++it) {
1032         protoObject = asObject(currStructure->prototypeForLookup(callFrame));
1033         currStructure = it->get();
1034         testPrototype(protoObject, bucketsOfFail, stubInfo);
1035     }
1036     ASSERT(protoObject);
1037
1038     bool needsStubLink = false;
1039     bool isDirect = false;
1040     if (slot.cachedPropertyType() == PropertySlot::Getter) {
1041         needsStubLink = true;
1042         compileGetDirectOffset(protoObject, regT2, regT1, cachedOffset);
1043         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
1044         stubCall.addArgument(regT1);
1045         stubCall.addArgument(regT0);
1046         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
1047         stubCall.call();
1048     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
1049         needsStubLink = true;
1050         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
1051         stubCall.addArgument(TrustedImmPtr(protoObject));
1052         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
1053         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
1054         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
1055         stubCall.call();
1056     } else {
1057         isDirect = true;
1058         compileGetDirectOffset(protoObject, regT1, regT0, cachedOffset);
1059     }
1060
1061     Jump success = jump();
1062
1063     LinkBuffer patchBuffer(*m_vm, this, m_codeBlock);
1064     if (needsStubLink) {
1065         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
1066             if (iter->to)
1067                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
1068         }
1069     }
1070     // Use the patch information to link the failure cases back to the original slow case routine.
1071     CodeLocationLabel lastProtoBegin = CodeLocationLabel(JITStubRoutine::asCodePtr(prototypeStructures->list[currentIndex - 1].stubRoutine));
1072
1073     patchBuffer.link(bucketsOfFail, lastProtoBegin);
1074
1075     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
1076     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
1077
1078     RefPtr<JITStubRoutine> stubRoutine = createJITStubRoutine(
1079         FINALIZE_CODE(
1080             patchBuffer,
1081             ("Baseline get_by_id chain list stub for %s, return point %p",
1082                 toCString(*m_codeBlock).data(), stubInfo->hotPathBegin.labelAtOffset(
1083                     stubInfo->patch.baseline.u.get.putResult).executableAddress())),
1084         *m_vm,
1085         m_codeBlock->ownerExecutable(),
1086         needsStubLink);
1087
1088     // Track the stub we have created so that it will be deleted later.
1089     prototypeStructures->list[currentIndex].set(callFrame->vm(), m_codeBlock->ownerExecutable(), stubRoutine, structure, chain, isDirect);
1090
1091     // Finally patch the jump to slow case back in the hot path to jump here instead.
1092     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
1093     RepatchBuffer repatchBuffer(m_codeBlock);
1094     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine->code().code()));
1095 }
1096
1097 void JIT::privateCompileGetByIdChain(StructureStubInfo* stubInfo, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, PropertyOffset cachedOffset, ReturnAddressPtr returnAddress, CallFrame* callFrame)
1098 {
1099     // regT0 holds a JSCell*
1100     ASSERT(count);
1101
1102     JumpList bucketsOfFail;
1103
1104     // Check eax is an object of the right Structure.
1105     bucketsOfFail.append(checkStructure(regT0, structure));
1106
1107     Structure* currStructure = structure;
1108     WriteBarrier<Structure>* it = chain->head();
1109     JSObject* protoObject = 0;
1110     for (unsigned i = 0; i < count; ++i, ++it) {
1111         protoObject = asObject(currStructure->prototypeForLookup(callFrame));
1112         currStructure = it->get();
1113         testPrototype(protoObject, bucketsOfFail, stubInfo);
1114     }
1115     ASSERT(protoObject);
1116
1117     bool needsStubLink = false;
1118     if (slot.cachedPropertyType() == PropertySlot::Getter) {
1119         needsStubLink = true;
1120         compileGetDirectOffset(protoObject, regT2, regT1, cachedOffset);
1121         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
1122         stubCall.addArgument(regT1);
1123         stubCall.addArgument(regT0);
1124         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
1125         stubCall.call();
1126     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
1127         needsStubLink = true;
1128         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
1129         stubCall.addArgument(TrustedImmPtr(protoObject));
1130         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
1131         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
1132         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
1133         stubCall.call();
1134     } else
1135         compileGetDirectOffset(protoObject, regT1, regT0, cachedOffset);
1136     Jump success = jump();
1137
1138     LinkBuffer patchBuffer(*m_vm, this, m_codeBlock);
1139     if (needsStubLink) {
1140         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
1141             if (iter->to)
1142                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
1143         }
1144     }
1145     // Use the patch information to link the failure cases back to the original slow case routine.
1146     patchBuffer.link(bucketsOfFail, stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin));
1147
1148     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
1149     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
1150
1151     // Track the stub we have created so that it will be deleted later.
1152     RefPtr<JITStubRoutine> stubRoutine = createJITStubRoutine(
1153         FINALIZE_CODE(
1154             patchBuffer,
1155             ("Baseline get_by_id chain stub for %s, return point %p",
1156                 toCString(*m_codeBlock).data(), stubInfo->hotPathBegin.labelAtOffset(
1157                     stubInfo->patch.baseline.u.get.putResult).executableAddress())),
1158         *m_vm,
1159         m_codeBlock->ownerExecutable(),
1160         needsStubLink);
1161     stubInfo->stubRoutine = stubRoutine;
1162
1163     // Finally patch the jump to slow case back in the hot path to jump here instead.
1164     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
1165     RepatchBuffer repatchBuffer(m_codeBlock);
1166     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine->code().code()));
1167
1168     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
1169     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_proto_list));
1170 }
1171
1172 void JIT::compileGetDirectOffset(RegisterID base, RegisterID resultTag, RegisterID resultPayload, RegisterID offset, FinalObjectMode finalObjectMode)
1173 {
1174     ASSERT(sizeof(JSValue) == 8);
1175
1176     if (finalObjectMode == MayBeFinal) {
1177         Jump isInline = branch32(LessThan, offset, TrustedImm32(firstOutOfLineOffset));
1178         loadPtr(Address(base, JSObject::butterflyOffset()), base);
1179         neg32(offset);
1180         Jump done = jump();
1181         isInline.link(this);
1182         addPtr(TrustedImmPtr(JSObject::offsetOfInlineStorage() - (firstOutOfLineOffset - 2) * sizeof(EncodedJSValue)), base);
1183         done.link(this);
1184     } else {
1185 #if !ASSERT_DISABLED
1186         Jump isOutOfLine = branch32(GreaterThanOrEqual, offset, TrustedImm32(firstOutOfLineOffset));
1187         breakpoint();
1188         isOutOfLine.link(this);
1189 #endif
1190         loadPtr(Address(base, JSObject::butterflyOffset()), base);
1191         neg32(offset);
1192     }
1193     load32(BaseIndex(base, offset, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload) + (firstOutOfLineOffset - 2) * sizeof(EncodedJSValue)), resultPayload);
1194     load32(BaseIndex(base, offset, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag) + (firstOutOfLineOffset - 2) * sizeof(EncodedJSValue)), resultTag);
1195 }
1196
1197 void JIT::emit_op_get_by_pname(Instruction* currentInstruction)
1198 {
1199     unsigned dst = currentInstruction[1].u.operand;
1200     unsigned base = currentInstruction[2].u.operand;
1201     unsigned property = currentInstruction[3].u.operand;
1202     unsigned expected = currentInstruction[4].u.operand;
1203     unsigned iter = currentInstruction[5].u.operand;
1204     unsigned i = currentInstruction[6].u.operand;
1205
1206     emitLoad2(property, regT1, regT0, base, regT3, regT2);
1207     emitJumpSlowCaseIfNotJSCell(property, regT1);
1208     addSlowCase(branchPtr(NotEqual, regT0, payloadFor(expected)));
1209     // Property registers are now available as the property is known
1210     emitJumpSlowCaseIfNotJSCell(base, regT3);
1211     emitLoadPayload(iter, regT1);
1212
1213     // Test base's structure
1214     loadPtr(Address(regT2, JSCell::structureOffset()), regT0);
1215     addSlowCase(branchPtr(NotEqual, regT0, Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_cachedStructure))));
1216     load32(addressFor(i), regT3);
1217     sub32(TrustedImm32(1), regT3);
1218     addSlowCase(branch32(AboveOrEqual, regT3, Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_numCacheableSlots))));
1219     Jump inlineProperty = branch32(Below, regT3, Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_cachedStructureInlineCapacity)));
1220     add32(TrustedImm32(firstOutOfLineOffset), regT3);
1221     sub32(Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_cachedStructureInlineCapacity)), regT3);
1222     inlineProperty.link(this);
1223     compileGetDirectOffset(regT2, regT1, regT0, regT3);
1224
1225     emitStore(dst, regT1, regT0);
1226     map(m_bytecodeOffset + OPCODE_LENGTH(op_get_by_pname), dst, regT1, regT0);
1227 }
1228
1229 void JIT::emitSlow_op_get_by_pname(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
1230 {
1231     unsigned dst = currentInstruction[1].u.operand;
1232     unsigned base = currentInstruction[2].u.operand;
1233     unsigned property = currentInstruction[3].u.operand;
1234
1235     linkSlowCaseIfNotJSCell(iter, property);
1236     linkSlowCase(iter);
1237     linkSlowCaseIfNotJSCell(iter, base);
1238     linkSlowCase(iter);
1239     linkSlowCase(iter);
1240
1241     JITStubCall stubCall(this, cti_op_get_by_val_generic);
1242     stubCall.addArgument(base);
1243     stubCall.addArgument(property);
1244     stubCall.call(dst);
1245 }
1246
1247 void JIT::emit_op_get_scoped_var(Instruction* currentInstruction)
1248 {
1249     int dst = currentInstruction[1].u.operand;
1250     int index = currentInstruction[2].u.operand;
1251     int skip = currentInstruction[3].u.operand;
1252
1253     emitGetFromCallFrameHeaderPtr(JSStack::ScopeChain, regT2);
1254     bool checkTopLevel = m_codeBlock->codeType() == FunctionCode && m_codeBlock->needsFullScopeChain();
1255     ASSERT(skip || !checkTopLevel);
1256     if (checkTopLevel && skip--) {
1257         Jump activationNotCreated;
1258         if (checkTopLevel)
1259             activationNotCreated = branch32(Equal, tagFor(m_codeBlock->activationRegister()), TrustedImm32(JSValue::EmptyValueTag));
1260         loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
1261         activationNotCreated.link(this);
1262     }
1263     while (skip--)
1264         loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
1265
1266     loadPtr(Address(regT2, JSVariableObject::offsetOfRegisters()), regT2);
1267
1268     emitLoad(index, regT1, regT0, regT2);
1269     emitValueProfilingSite();
1270     emitStore(dst, regT1, regT0);
1271     map(m_bytecodeOffset + OPCODE_LENGTH(op_get_scoped_var), dst, regT1, regT0);
1272 }
1273
1274 void JIT::emit_op_put_scoped_var(Instruction* currentInstruction)
1275 {
1276     int index = currentInstruction[1].u.operand;
1277     int skip = currentInstruction[2].u.operand;
1278     int value = currentInstruction[3].u.operand;
1279
1280     emitLoad(value, regT1, regT0);
1281
1282     emitGetFromCallFrameHeaderPtr(JSStack::ScopeChain, regT2);
1283     bool checkTopLevel = m_codeBlock->codeType() == FunctionCode && m_codeBlock->needsFullScopeChain();
1284     ASSERT(skip || !checkTopLevel);
1285     if (checkTopLevel && skip--) {
1286         Jump activationNotCreated;
1287         if (checkTopLevel)
1288             activationNotCreated = branch32(Equal, tagFor(m_codeBlock->activationRegister()), TrustedImm32(JSValue::EmptyValueTag));
1289         loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
1290         activationNotCreated.link(this);
1291     }
1292     while (skip--)
1293         loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
1294
1295     loadPtr(Address(regT2, JSVariableObject::offsetOfRegisters()), regT3);
1296     emitStore(index, regT1, regT0, regT3);
1297     emitWriteBarrier(regT2, regT1, regT0, regT1, ShouldFilterImmediates, WriteBarrierForVariableAccess);
1298 }
1299
1300 void JIT::emit_op_init_global_const(Instruction* currentInstruction)
1301 {
1302     WriteBarrier<Unknown>* registerPointer = currentInstruction[1].u.registerPointer;
1303     int value = currentInstruction[2].u.operand;
1304
1305     JSGlobalObject* globalObject = m_codeBlock->globalObject();
1306
1307     emitLoad(value, regT1, regT0);
1308
1309     if (Heap::isWriteBarrierEnabled()) {
1310         move(TrustedImmPtr(globalObject), regT2);
1311
1312         emitWriteBarrier(globalObject, regT1, regT3, ShouldFilterImmediates, WriteBarrierForVariableAccess);
1313     }
1314
1315     store32(regT1, registerPointer->tagPointer());
1316     store32(regT0, registerPointer->payloadPointer());
1317     map(m_bytecodeOffset + OPCODE_LENGTH(op_init_global_const), value, regT1, regT0);
1318 }
1319
1320 void JIT::emit_op_init_global_const_check(Instruction* currentInstruction)
1321 {
1322     WriteBarrier<Unknown>* registerPointer = currentInstruction[1].u.registerPointer;
1323     int value = currentInstruction[2].u.operand;
1324
1325     JSGlobalObject* globalObject = m_codeBlock->globalObject();
1326
1327     emitLoad(value, regT1, regT0);
1328
1329     addSlowCase(branchTest8(NonZero, AbsoluteAddress(currentInstruction[3].u.predicatePointer)));
1330
1331     if (Heap::isWriteBarrierEnabled()) {
1332         move(TrustedImmPtr(globalObject), regT2);
1333         emitWriteBarrier(globalObject, regT1, regT3, ShouldFilterImmediates, WriteBarrierForVariableAccess);
1334     }
1335
1336     store32(regT1, registerPointer->tagPointer());
1337     store32(regT0, registerPointer->payloadPointer());
1338     unmap();
1339 }
1340
1341 void JIT::emitSlow_op_init_global_const_check(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
1342 {
1343     linkSlowCase(iter);
1344
1345     JITStubCall stubCall(this, cti_op_init_global_const_check);
1346     stubCall.addArgument(regT1, regT0);
1347     stubCall.addArgument(TrustedImm32(currentInstruction[4].u.operand));
1348     stubCall.call();
1349 }
1350
1351 void JIT::resetPatchGetById(RepatchBuffer& repatchBuffer, StructureStubInfo* stubInfo)
1352 {
1353     repatchBuffer.relink(stubInfo->callReturnLocation, cti_op_get_by_id);
1354     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.get.structureToCompare), reinterpret_cast<void*>(unusedPointer));
1355     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.get.displacementLabel1), 0);
1356     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.get.displacementLabel2), 0);
1357     repatchBuffer.relink(stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck), stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin));
1358 }
1359
1360 void JIT::resetPatchPutById(RepatchBuffer& repatchBuffer, StructureStubInfo* stubInfo)
1361 {
1362     if (isDirectPutById(stubInfo))
1363         repatchBuffer.relink(stubInfo->callReturnLocation, cti_op_put_by_id_direct);
1364     else
1365         repatchBuffer.relink(stubInfo->callReturnLocation, cti_op_put_by_id);
1366     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.put.structureToCompare), reinterpret_cast<void*>(unusedPointer));
1367     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(stubInfo->patch.baseline.u.put.displacementLabel1), 0);
1368     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(stubInfo->patch.baseline.u.put.displacementLabel2), 0);
1369 }
1370
1371 } // namespace JSC
1372
1373 #endif // USE(JSVALUE32_64)
1374 #endif // ENABLE(JIT)