Source/JavaScriptCore/jit/JITPropertyAccess.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 #include "JIT.h"
  30
  31 #include "CodeBlock.h"
  32 #include "GetterSetter.h"
  33 #include "JITInlineMethods.h"
  34 #include "JITStubCall.h"
  35 #include "JSArray.h"
  36 #include "JSFunction.h"
  37 #include "JSPropertyNameIterator.h"
  38 #include "Interpreter.h"
  39 #include "LinkBuffer.h"
  40 #include "RepatchBuffer.h"
  41 #include "ResultType.h"
  42 #include "SamplingTool.h"
  43
  44 #ifndef NDEBUG
  45 #include <stdio.h>
  46 #endif
  47
  48 using namespace std;
  49
  50 namespace JSC {
  51 #if USE(JSVALUE64)
  52
  53 JIT::CodeRef JIT::stringGetByValStubGenerator(JSGlobalData* globalData)
  54 {
  55     JSInterfaceJIT jit;
  56     JumpList failures;
  57     failures.append(jit.branchPtr(NotEqual, Address(regT0), TrustedImmPtr(globalData->jsStringVPtr)));
  58     failures.append(jit.branchTest32(NonZero, Address(regT0, OBJECT_OFFSETOF(JSString, m_fiberCount))));
  59
  60     // Load string length to regT2, and start the process of loading the data pointer into regT0
  61     jit.load32(Address(regT0, ThunkHelpers::jsStringLengthOffset()), regT2);
  62     jit.loadPtr(Address(regT0, ThunkHelpers::jsStringValueOffset()), regT0);
  63     jit.loadPtr(Address(regT0, ThunkHelpers::stringImplDataOffset()), regT0);
  64
  65     // Do an unsigned compare to simultaneously filter negative indices as well as indices that are too large
  66     failures.append(jit.branch32(AboveOrEqual, regT1, regT2));
  67
  68     // Load the character
  69     jit.load16(BaseIndex(regT0, regT1, TimesTwo, 0), regT0);
  70
  71     failures.append(jit.branch32(AboveOrEqual, regT0, TrustedImm32(0x100)));
  72     jit.move(TrustedImmPtr(globalData->smallStrings.singleCharacterStrings()), regT1);
  73     jit.loadPtr(BaseIndex(regT1, regT0, ScalePtr, 0), regT0);
  74     jit.ret();
  75
  76     failures.link(&jit);
  77     jit.move(TrustedImm32(0), regT0);
  78     jit.ret();
  79
  80     LinkBuffer patchBuffer(*globalData, &jit);
  81     return patchBuffer.finalizeCode();
  82 }
  83
  84 void JIT::emit_op_get_by_val(Instruction* currentInstruction)
  85 {
  86     unsigned dst = currentInstruction[1].u.operand;
  87     unsigned base = currentInstruction[2].u.operand;
  88     unsigned property = currentInstruction[3].u.operand;
  89
  90     emitGetVirtualRegisters(base, regT0, property, regT1);
  91     emitJumpSlowCaseIfNotImmediateInteger(regT1);
  92
  93     // This is technically incorrect - we're zero-extending an int32.  On the hot path this doesn't matter.
  94     // We check the value as if it was a uint32 against the m_vectorLength - which will always fail if
  95     // number was signed since m_vectorLength is always less than intmax (since the total allocation
  96     // size is always less than 4Gb).  As such zero extending wil have been correct (and extending the value
  97     // to 64-bits is necessary since it's used in the address calculation.  We zero extend rather than sign
  98     // extending since it makes it easier to re-tag the value in the slow case.
  99     zeroExtend32ToPtr(regT1, regT1);
 100
 101     emitJumpSlowCaseIfNotJSCell(regT0, base);
 102     addSlowCase(branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsArrayVPtr)));
 103
 104     loadPtr(Address(regT0, JSArray::storageOffset()), regT2);
 105     addSlowCase(branch32(AboveOrEqual, regT1, Address(regT0, JSArray::vectorLengthOffset())));
 106
 107     loadPtr(BaseIndex(regT2, regT1, ScalePtr, OBJECT_OFFSETOF(ArrayStorage, m_vector[0])), regT0);
 108     addSlowCase(branchTestPtr(Zero, regT0));
 109
 110     emitValueProfilingSite(FirstProfilingSite);
 111     emitPutVirtualRegister(dst);
 112 }
 113
 114 void JIT::emitSlow_op_get_by_val(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 115 {
 116     unsigned dst = currentInstruction[1].u.operand;
 117     unsigned base = currentInstruction[2].u.operand;
 118     unsigned property = currentInstruction[3].u.operand;
 119
 120     linkSlowCase(iter); // property int32 check
 121     linkSlowCaseIfNotJSCell(iter, base); // base cell check
 122     Jump nonCell = jump();
 123     linkSlowCase(iter); // base array check
 124     Jump notString = branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsStringVPtr));
 125     emitNakedCall(CodeLocationLabel(m_globalData->getCTIStub(stringGetByValStubGenerator).code()));
 126     Jump failed = branchTestPtr(Zero, regT0);
 127     emitPutVirtualRegister(dst, regT0);
 128     emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_get_by_val));
 129     failed.link(this);
 130     notString.link(this);
 131     nonCell.link(this);
 132
 133     linkSlowCase(iter); // vector length check
 134     linkSlowCase(iter); // empty value
 135
 136     JITStubCall stubCall(this, cti_op_get_by_val);
 137     stubCall.addArgument(base, regT2);
 138     stubCall.addArgument(property, regT2);
 139     stubCall.call(dst);
 140
 141     emitValueProfilingSite(SubsequentProfilingSite);
 142 }
 143
 144 void JIT::compileGetDirectOffset(RegisterID base, RegisterID result, RegisterID offset, RegisterID scratch)
 145 {
 146     loadPtr(Address(base, JSObject::offsetOfPropertyStorage()), scratch);
 147     loadPtr(BaseIndex(scratch, offset, ScalePtr, 0), result);
 148 }
 149
 150 void JIT::emit_op_get_by_pname(Instruction* currentInstruction)
 151 {
 152     unsigned dst = currentInstruction[1].u.operand;
 153     unsigned base = currentInstruction[2].u.operand;
 154     unsigned property = currentInstruction[3].u.operand;
 155     unsigned expected = currentInstruction[4].u.operand;
 156     unsigned iter = currentInstruction[5].u.operand;
 157     unsigned i = currentInstruction[6].u.operand;
 158
 159     emitGetVirtualRegister(property, regT0);
 160     addSlowCase(branchPtr(NotEqual, regT0, addressFor(expected)));
 161     emitGetVirtualRegisters(base, regT0, iter, regT1);
 162     emitJumpSlowCaseIfNotJSCell(regT0, base);
 163
 164     // Test base's structure
 165     loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
 166     addSlowCase(branchPtr(NotEqual, regT2, Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_cachedStructure))));
 167     load32(addressFor(i), regT3);
 168     sub32(TrustedImm32(1), regT3);
 169     addSlowCase(branch32(AboveOrEqual, regT3, Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_numCacheableSlots))));
 170     compileGetDirectOffset(regT0, regT0, regT3, regT1);
 171
 172     emitPutVirtualRegister(dst, regT0);
 173 }
 174
 175 void JIT::emitSlow_op_get_by_pname(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 176 {
 177     unsigned dst = currentInstruction[1].u.operand;
 178     unsigned base = currentInstruction[2].u.operand;
 179     unsigned property = currentInstruction[3].u.operand;
 180
 181     linkSlowCase(iter);
 182     linkSlowCaseIfNotJSCell(iter, base);
 183     linkSlowCase(iter);
 184     linkSlowCase(iter);
 185
 186     JITStubCall stubCall(this, cti_op_get_by_val);
 187     stubCall.addArgument(base, regT2);
 188     stubCall.addArgument(property, regT2);
 189     stubCall.call(dst);
 190 }
 191
 192 void JIT::emit_op_put_by_val(Instruction* currentInstruction)
 193 {
 194     unsigned base = currentInstruction[1].u.operand;
 195     unsigned property = currentInstruction[2].u.operand;
 196     unsigned value = currentInstruction[3].u.operand;
 197
 198     emitGetVirtualRegisters(base, regT0, property, regT1);
 199     emitJumpSlowCaseIfNotImmediateInteger(regT1);
 200     // See comment in op_get_by_val.
 201     zeroExtend32ToPtr(regT1, regT1);
 202     emitJumpSlowCaseIfNotJSCell(regT0, base);
 203     addSlowCase(branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsArrayVPtr)));
 204     addSlowCase(branch32(AboveOrEqual, regT1, Address(regT0, JSArray::vectorLengthOffset())));
 205
 206     loadPtr(Address(regT0, JSArray::storageOffset()), regT2);
 207     Jump empty = branchTestPtr(Zero, BaseIndex(regT2, regT1, ScalePtr, OBJECT_OFFSETOF(ArrayStorage, m_vector[0])));
 208
 209     Label storeResult(this);
 210     emitGetVirtualRegister(value, regT3);
 211     storePtr(regT3, BaseIndex(regT2, regT1, ScalePtr, OBJECT_OFFSETOF(ArrayStorage, m_vector[0])));
 212     Jump end = jump();
 213
 214     empty.link(this);
 215     add32(TrustedImm32(1), Address(regT2, OBJECT_OFFSETOF(ArrayStorage, m_numValuesInVector)));
 216     branch32(Below, regT1, Address(regT2, OBJECT_OFFSETOF(ArrayStorage, m_length))).linkTo(storeResult, this);
 217
 218     add32(TrustedImm32(1), regT1);
 219     store32(regT1, Address(regT2, OBJECT_OFFSETOF(ArrayStorage, m_length)));
 220     sub32(TrustedImm32(1), regT1);
 221     jump().linkTo(storeResult, this);
 222
 223     end.link(this);
 224
 225     emitWriteBarrier(regT0, regT3, regT1, regT3, ShouldFilterImmediates, WriteBarrierForPropertyAccess);
 226 }
 227
 228 void JIT::emitSlow_op_put_by_val(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 229 {
 230     unsigned base = currentInstruction[1].u.operand;
 231     unsigned property = currentInstruction[2].u.operand;
 232     unsigned value = currentInstruction[3].u.operand;
 233
 234     linkSlowCase(iter); // property int32 check
 235     linkSlowCaseIfNotJSCell(iter, base); // base cell check
 236     linkSlowCase(iter); // base not array check
 237     linkSlowCase(iter); // in vector check
 238
 239     JITStubCall stubPutByValCall(this, cti_op_put_by_val);
 240     stubPutByValCall.addArgument(regT0);
 241     stubPutByValCall.addArgument(property, regT2);
 242     stubPutByValCall.addArgument(value, regT2);
 243     stubPutByValCall.call();
 244 }
 245
 246 void JIT::emit_op_put_by_index(Instruction* currentInstruction)
 247 {
 248     JITStubCall stubCall(this, cti_op_put_by_index);
 249     stubCall.addArgument(currentInstruction[1].u.operand, regT2);
 250     stubCall.addArgument(TrustedImm32(currentInstruction[2].u.operand));
 251     stubCall.addArgument(currentInstruction[3].u.operand, regT2);
 252     stubCall.call();
 253 }
 254
 255 void JIT::emit_op_put_getter(Instruction* currentInstruction)
 256 {
 257     JITStubCall stubCall(this, cti_op_put_getter);
 258     stubCall.addArgument(currentInstruction[1].u.operand, regT2);
 259     stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[2].u.operand)));
 260     stubCall.addArgument(currentInstruction[3].u.operand, regT2);
 261     stubCall.call();
 262 }
 263
 264 void JIT::emit_op_put_setter(Instruction* currentInstruction)
 265 {
 266     JITStubCall stubCall(this, cti_op_put_setter);
 267     stubCall.addArgument(currentInstruction[1].u.operand, regT2);
 268     stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[2].u.operand)));
 269     stubCall.addArgument(currentInstruction[3].u.operand, regT2);
 270     stubCall.call();
 271 }
 272
 273 void JIT::emit_op_del_by_id(Instruction* currentInstruction)
 274 {
 275     JITStubCall stubCall(this, cti_op_del_by_id);
 276     stubCall.addArgument(currentInstruction[2].u.operand, regT2);
 277     stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[3].u.operand)));
 278     stubCall.call(currentInstruction[1].u.operand);
 279 }
 280
 281 void JIT::emit_op_method_check(Instruction* currentInstruction)
 282 {
 283     // Assert that the following instruction is a get_by_id.
 284     ASSERT(m_interpreter->getOpcodeID((currentInstruction + OPCODE_LENGTH(op_method_check))->u.opcode) == op_get_by_id);
 285
 286     currentInstruction += OPCODE_LENGTH(op_method_check);
 287     unsigned resultVReg = currentInstruction[1].u.operand;
 288     unsigned baseVReg = currentInstruction[2].u.operand;
 289     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 290
 291     emitGetVirtualRegister(baseVReg, regT0);
 292
 293     // Do the method check - check the object & its prototype's structure inline (this is the common case).
 294     m_methodCallCompilationInfo.append(MethodCallCompilationInfo(m_bytecodeOffset, m_propertyAccessCompilationInfo.size()));
 295     MethodCallCompilationInfo& info = m_methodCallCompilationInfo.last();
 296
 297     Jump notCell = emitJumpIfNotJSCell(regT0);
 298
 299     BEGIN_UNINTERRUPTED_SEQUENCE(sequenceMethodCheck);
 300
 301     Jump structureCheck = branchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), info.structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure)));
 302     DataLabelPtr protoStructureToCompare, protoObj = moveWithPatch(TrustedImmPtr(0), regT1);
 303     Jump protoStructureCheck = branchPtrWithPatch(NotEqual, Address(regT1, JSCell::structureOffset()), protoStructureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure)));
 304
 305     // This will be relinked to load the function without doing a load.
 306     DataLabelPtr putFunction = moveWithPatch(TrustedImmPtr(0), regT0);
 307
 308     END_UNINTERRUPTED_SEQUENCE(sequenceMethodCheck);
 309
 310     Jump match = jump();
 311
 312     ASSERT_JIT_OFFSET_UNUSED(protoObj, differenceBetween(info.structureToCompare, protoObj), patchOffsetMethodCheckProtoObj);
 313     ASSERT_JIT_OFFSET(differenceBetween(info.structureToCompare, protoStructureToCompare), patchOffsetMethodCheckProtoStruct);
 314     ASSERT_JIT_OFFSET_UNUSED(putFunction, differenceBetween(info.structureToCompare, putFunction), patchOffsetMethodCheckPutFunction);
 315
 316     // Link the failure cases here.
 317     notCell.link(this);
 318     structureCheck.link(this);
 319     protoStructureCheck.link(this);
 320
 321     // Do a regular(ish) get_by_id (the slow case will be link to
 322     // cti_op_get_by_id_method_check instead of cti_op_get_by_id.
 323     compileGetByIdHotPath(baseVReg, ident);
 324
 325     match.link(this);
 326     emitValueProfilingSite(FirstProfilingSite);
 327     emitPutVirtualRegister(resultVReg);
 328
 329     // We've already generated the following get_by_id, so make sure it's skipped over.
 330     m_bytecodeOffset += OPCODE_LENGTH(op_get_by_id);
 331 }
 332
 333 void JIT::emitSlow_op_method_check(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 334 {
 335     currentInstruction += OPCODE_LENGTH(op_method_check);
 336     unsigned resultVReg = currentInstruction[1].u.operand;
 337     unsigned baseVReg = currentInstruction[2].u.operand;
 338     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 339
 340     compileGetByIdSlowCase(resultVReg, baseVReg, ident, iter, true);
 341
 342     // We've already generated the following get_by_id, so make sure it's skipped over.
 343     m_bytecodeOffset += OPCODE_LENGTH(op_get_by_id);
 344 }
 345
 346 void JIT::emit_op_get_by_id(Instruction* currentInstruction)
 347 {
 348     unsigned resultVReg = currentInstruction[1].u.operand;
 349     unsigned baseVReg = currentInstruction[2].u.operand;
 350     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 351
 352     emitGetVirtualRegister(baseVReg, regT0);
 353     compileGetByIdHotPath(baseVReg, ident);
 354     emitValueProfilingSite(FirstProfilingSite);
 355     emitPutVirtualRegister(resultVReg);
 356 }
 357
 358 void JIT::compileGetByIdHotPath(int baseVReg, Identifier*)
 359 {
 360     // As for put_by_id, get_by_id requires the offset of the Structure and the offset of the access to be patched.
 361     // Additionally, for get_by_id we need patch the offset of the branch to the slow case (we patch this to jump
 362     // to array-length / prototype access tranpolines, and finally we also the the property-map access offset as a label
 363     // to jump back to if one of these trampolies finds a match.
 364
 365     emitJumpSlowCaseIfNotJSCell(regT0, baseVReg);
 366
 367     BEGIN_UNINTERRUPTED_SEQUENCE(sequenceGetByIdHotPath);
 368
 369     Label hotPathBegin(this);
 370     m_propertyAccessCompilationInfo.append(PropertyStubCompilationInfo());
 371     m_propertyAccessCompilationInfo.last().bytecodeIndex = m_bytecodeOffset;
 372     m_propertyAccessCompilationInfo.last().hotPathBegin = hotPathBegin;
 373
 374     DataLabelPtr structureToCompare;
 375     Jump structureCheck = branchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure)));
 376     addSlowCase(structureCheck);
 377     ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, structureToCompare), patchOffsetGetByIdStructure);
 378     ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, structureCheck), patchOffsetGetByIdBranchToSlowCase)
 379
 380     loadPtr(Address(regT0, JSObject::offsetOfPropertyStorage()), regT0);
 381     DataLabelCompact displacementLabel = loadPtrWithCompactAddressOffsetPatch(Address(regT0, patchGetByIdDefaultOffset), regT0);
 382     ASSERT_JIT_OFFSET_UNUSED(displacementLabel, differenceBetween(hotPathBegin, displacementLabel), patchOffsetGetByIdPropertyMapOffset);
 383
 384     Label putResult(this);
 385
 386     END_UNINTERRUPTED_SEQUENCE(sequenceGetByIdHotPath);
 387
 388     ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, putResult), patchOffsetGetByIdPutResult);
 389 }
 390
 391 void JIT::emitSlow_op_get_by_id(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 392 {
 393     unsigned resultVReg = currentInstruction[1].u.operand;
 394     unsigned baseVReg = currentInstruction[2].u.operand;
 395     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 396
 397     compileGetByIdSlowCase(resultVReg, baseVReg, ident, iter, false);
 398     emitValueProfilingSite(SubsequentProfilingSite);
 399 }
 400
 401 void JIT::compileGetByIdSlowCase(int resultVReg, int baseVReg, Identifier* ident, Vector<SlowCaseEntry>::iterator& iter, bool isMethodCheck)
 402 {
 403     // As for the hot path of get_by_id, above, we ensure that we can use an architecture specific offset
 404     // so that we only need track one pointer into the slow case code - we track a pointer to the location
 405     // of the call (which we can use to look up the patch information), but should a array-length or
 406     // prototype access trampoline fail we want to bail out back to here.  To do so we can subtract back
 407     // the distance from the call to the head of the slow case.
 408
 409     linkSlowCaseIfNotJSCell(iter, baseVReg);
 410     linkSlowCase(iter);
 411
 412     BEGIN_UNINTERRUPTED_SEQUENCE(sequenceGetByIdSlowCase);
 413
 414 #ifndef NDEBUG
 415     Label coldPathBegin(this);
 416 #endif
 417     JITStubCall stubCall(this, isMethodCheck ? cti_op_get_by_id_method_check : cti_op_get_by_id);
 418     stubCall.addArgument(regT0);
 419     stubCall.addArgument(TrustedImmPtr(ident));
 420     Call call = stubCall.call(resultVReg);
 421
 422     END_UNINTERRUPTED_SEQUENCE(sequenceGetByIdSlowCase);
 423
 424     ASSERT_JIT_OFFSET(differenceBetween(coldPathBegin, call), patchOffsetGetByIdSlowCaseCall);
 425
 426     // Track the location of the call; this will be used to recover patch information.
 427     m_propertyAccessCompilationInfo[m_propertyAccessInstructionIndex++].callReturnLocation = call;
 428 }
 429
 430 void JIT::emit_op_put_by_id(Instruction* currentInstruction)
 431 {
 432     unsigned baseVReg = currentInstruction[1].u.operand;
 433     unsigned valueVReg = currentInstruction[3].u.operand;
 434
 435     // In order to be able to patch both the Structure, and the object offset, we store one pointer,
 436     // to just after the arguments have been loaded into registers 'hotPathBegin', and we generate code
 437     // such that the Structure & offset are always at the same distance from this.
 438
 439     emitGetVirtualRegisters(baseVReg, regT0, valueVReg, regT1);
 440
 441     // Jump to a slow case if either the base object is an immediate, or if the Structure does not match.
 442     emitJumpSlowCaseIfNotJSCell(regT0, baseVReg);
 443
 444     BEGIN_UNINTERRUPTED_SEQUENCE(sequencePutById);
 445
 446     Label hotPathBegin(this);
 447     m_propertyAccessCompilationInfo.append(PropertyStubCompilationInfo());
 448     m_propertyAccessCompilationInfo.last().bytecodeIndex = m_bytecodeOffset;
 449     m_propertyAccessCompilationInfo.last().hotPathBegin = hotPathBegin;
 450
 451     // It is important that the following instruction plants a 32bit immediate, in order that it can be patched over.
 452     DataLabelPtr structureToCompare;
 453     addSlowCase(branchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure))));
 454     ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, structureToCompare), patchOffsetPutByIdStructure);
 455
 456     loadPtr(Address(regT0, JSObject::offsetOfPropertyStorage()), regT2);
 457     DataLabel32 displacementLabel = storePtrWithAddressOffsetPatch(regT1, Address(regT2, patchPutByIdDefaultOffset));
 458
 459     END_UNINTERRUPTED_SEQUENCE(sequencePutById);
 460
 461     emitWriteBarrier(regT0, regT1, regT2, regT3, ShouldFilterImmediates, WriteBarrierForPropertyAccess);
 462
 463     ASSERT_JIT_OFFSET_UNUSED(displacementLabel, differenceBetween(hotPathBegin, displacementLabel), patchOffsetPutByIdPropertyMapOffset);
 464 }
 465
 466 void JIT::emitSlow_op_put_by_id(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 467 {
 468     unsigned baseVReg = currentInstruction[1].u.operand;
 469     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[2].u.operand));
 470     unsigned direct = currentInstruction[8].u.operand;
 471
 472     linkSlowCaseIfNotJSCell(iter, baseVReg);
 473     linkSlowCase(iter);
 474
 475     JITStubCall stubCall(this, direct ? cti_op_put_by_id_direct : cti_op_put_by_id);
 476     stubCall.addArgument(regT0);
 477     stubCall.addArgument(TrustedImmPtr(ident));
 478     stubCall.addArgument(regT1);
 479     Call call = stubCall.call();
 480
 481     // Track the location of the call; this will be used to recover patch information.
 482     m_propertyAccessCompilationInfo[m_propertyAccessInstructionIndex++].callReturnLocation = call;
 483 }
 484
 485 // Compile a store into an object's property storage.  May overwrite the
 486 // value in objectReg.
 487 void JIT::compilePutDirectOffset(RegisterID base, RegisterID value, size_t cachedOffset)
 488 {
 489     int offset = cachedOffset * sizeof(JSValue);
 490     loadPtr(Address(base, JSObject::offsetOfPropertyStorage()), base);
 491     storePtr(value, Address(base, offset));
 492 }
 493
 494 // Compile a load from an object's property storage.  May overwrite base.
 495 void JIT::compileGetDirectOffset(RegisterID base, RegisterID result, size_t cachedOffset)
 496 {
 497     int offset = cachedOffset * sizeof(JSValue);
 498     loadPtr(Address(base, JSObject::offsetOfPropertyStorage()), result);
 499     loadPtr(Address(result, offset), result);
 500 }
 501
 502 void JIT::compileGetDirectOffset(JSObject* base, RegisterID result, size_t cachedOffset)
 503 {
 504     loadPtr(base->addressOfPropertyStorage(), result);
 505     loadPtr(Address(result, cachedOffset * sizeof(WriteBarrier<Unknown>)), result);
 506 }
 507
 508 void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure* oldStructure, Structure* newStructure, size_t cachedOffset, StructureChain* chain, ReturnAddressPtr returnAddress, bool direct)
 509 {
 510     JumpList failureCases;
 511     // Check eax is an object of the right Structure.
 512     failureCases.append(emitJumpIfNotJSCell(regT0));
 513     failureCases.append(branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(oldStructure)));
 514     testPrototype(oldStructure->storedPrototype(), failureCases);
 515
 516     // ecx = baseObject->m_structure
 517     if (!direct) {
 518         for (WriteBarrier<Structure>* it = chain->head(); *it; ++it)
 519             testPrototype((*it)->storedPrototype(), failureCases);
 520     }
 521
 522     Call callTarget;
 523
 524     // emit a call only if storage realloc is needed
 525     bool willNeedStorageRealloc = oldStructure->propertyStorageCapacity() != newStructure->propertyStorageCapacity();
 526     if (willNeedStorageRealloc) {
 527         // This trampoline was called to like a JIT stub; before we can can call again we need to
 528         // remove the return address from the stack, to prevent the stack from becoming misaligned.
 529         preserveReturnAddressAfterCall(regT3);
 530
 531         JITStubCall stubCall(this, cti_op_put_by_id_transition_realloc);
 532         stubCall.skipArgument(); // base
 533         stubCall.skipArgument(); // ident
 534         stubCall.skipArgument(); // value
 535         stubCall.addArgument(TrustedImm32(oldStructure->propertyStorageCapacity()));
 536         stubCall.addArgument(TrustedImm32(newStructure->propertyStorageCapacity()));
 537         stubCall.call(regT0);
 538         emitGetJITStubArg(2, regT1);
 539
 540         restoreReturnAddressBeforeReturn(regT3);
 541     }
 542
 543     // Planting the new structure triggers the write barrier so we need
 544     // an unconditional barrier here.
 545     emitWriteBarrier(regT0, regT1, regT2, regT3, UnconditionalWriteBarrier, WriteBarrierForPropertyAccess);
 546
 547     storePtr(TrustedImmPtr(newStructure), Address(regT0, JSCell::structureOffset()));
 548     compilePutDirectOffset(regT0, regT1, cachedOffset);
 549
 550     ret();
 551
 552     ASSERT(!failureCases.empty());
 553     failureCases.link(this);
 554     restoreArgumentReferenceForTrampoline();
 555     Call failureCall = tailRecursiveCall();
 556
 557     LinkBuffer patchBuffer(*m_globalData, this);
 558
 559     patchBuffer.link(failureCall, FunctionPtr(direct ? cti_op_put_by_id_direct_fail : cti_op_put_by_id_fail));
 560
 561     if (willNeedStorageRealloc) {
 562         ASSERT(m_calls.size() == 1);
 563         patchBuffer.link(m_calls[0].from, FunctionPtr(cti_op_put_by_id_transition_realloc));
 564     }
 565
 566     stubInfo->stubRoutine = patchBuffer.finalizeCode();
 567     RepatchBuffer repatchBuffer(m_codeBlock);
 568     repatchBuffer.relinkCallerToTrampoline(returnAddress, CodeLocationLabel(stubInfo->stubRoutine.code()));
 569 }
 570
 571 void JIT::patchGetByIdSelf(CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, size_t cachedOffset, ReturnAddressPtr returnAddress)
 572 {
 573     RepatchBuffer repatchBuffer(codeBlock);
 574
 575     // We don't want to patch more than once - in future go to cti_op_get_by_id_generic.
 576     // Should probably go to cti_op_get_by_id_fail, but that doesn't do anything interesting right now.
 577     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_self_fail));
 578
 579     int offset = sizeof(JSValue) * cachedOffset;
 580
 581     // Patch the offset into the propoerty map to load from, then patch the Structure to look for.
 582     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(patchOffsetGetByIdStructure), structure);
 583     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(patchOffsetGetByIdPropertyMapOffset), offset);
 584 }
 585
 586 void JIT::patchPutByIdReplace(CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, size_t cachedOffset, ReturnAddressPtr returnAddress, bool direct)
 587 {
 588     RepatchBuffer repatchBuffer(codeBlock);
 589
 590     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
 591     // Should probably go to cti_op_put_by_id_fail, but that doesn't do anything interesting right now.
 592     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(direct ? cti_op_put_by_id_direct_generic : cti_op_put_by_id_generic));
 593
 594     int offset = sizeof(JSValue) * cachedOffset;
 595
 596     // Patch the offset into the propoerty map to load from, then patch the Structure to look for.
 597     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(patchOffsetPutByIdStructure), structure);
 598     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(patchOffsetPutByIdPropertyMapOffset), offset);
 599 }
 600
 601 void JIT::privateCompilePatchGetArrayLength(ReturnAddressPtr returnAddress)
 602 {
 603     StructureStubInfo* stubInfo = &m_codeBlock->getStubInfo(returnAddress);
 604
 605     // Check eax is an array
 606     Jump failureCases1 = branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsArrayVPtr));
 607
 608     // Checks out okay! - get the length from the storage
 609     loadPtr(Address(regT0, JSArray::storageOffset()), regT3);
 610     load32(Address(regT3, OBJECT_OFFSETOF(ArrayStorage, m_length)), regT2);
 611     Jump failureCases2 = branch32(LessThan, regT2, TrustedImm32(0));
 612
 613     emitFastArithIntToImmNoCheck(regT2, regT0);
 614     Jump success = jump();
 615
 616     LinkBuffer patchBuffer(*m_globalData, this);
 617
 618     // Use the patch information to link the failure cases back to the original slow case routine.
 619     CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall);
 620     patchBuffer.link(failureCases1, slowCaseBegin);
 621     patchBuffer.link(failureCases2, slowCaseBegin);
 622
 623     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 624     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
 625
 626     // Track the stub we have created so that it will be deleted later.
 627     stubInfo->stubRoutine = patchBuffer.finalizeCode();
 628
 629     // Finally patch the jump to slow case back in the hot path to jump here instead.
 630     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
 631     RepatchBuffer repatchBuffer(m_codeBlock);
 632     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubInfo->stubRoutine.code()));
 633
 634     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
 635     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_array_fail));
 636 }
 637
 638 void JIT::privateCompileGetByIdProto(StructureStubInfo* stubInfo, Structure* structure, Structure* prototypeStructure, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, ReturnAddressPtr returnAddress, CallFrame* callFrame)
 639 {
 640     // The prototype object definitely exists (if this stub exists the CodeBlock is referencing a Structure that is
 641     // referencing the prototype object - let's speculatively load it's table nice and early!)
 642     JSObject* protoObject = asObject(structure->prototypeForLookup(callFrame));
 643
 644     // Check eax is an object of the right Structure.
 645     Jump failureCases1 = checkStructure(regT0, structure);
 646
 647     // Check the prototype object's Structure had not changed.
 648     move(TrustedImmPtr(protoObject), regT3);
 649     Jump failureCases2 = branchPtr(NotEqual, Address(regT3, JSCell::structureOffset()), TrustedImmPtr(prototypeStructure));
 650
 651     bool needsStubLink = false;
 652
 653     // Checks out okay!
 654     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 655         needsStubLink = true;
 656         compileGetDirectOffset(protoObject, regT1, cachedOffset);
 657         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 658         stubCall.addArgument(regT1);
 659         stubCall.addArgument(regT0);
 660         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 661         stubCall.call();
 662     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 663         needsStubLink = true;
 664         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 665         stubCall.addArgument(TrustedImmPtr(protoObject));
 666         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 667         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 668         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 669         stubCall.call();
 670     } else
 671         compileGetDirectOffset(protoObject, regT0, cachedOffset);
 672     Jump success = jump();
 673     LinkBuffer patchBuffer(*m_globalData, this);
 674
 675     // Use the patch information to link the failure cases back to the original slow case routine.
 676     CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall);
 677     patchBuffer.link(failureCases1, slowCaseBegin);
 678     patchBuffer.link(failureCases2, slowCaseBegin);
 679
 680     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 681     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
 682
 683     if (needsStubLink) {
 684         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 685             if (iter->to)
 686                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 687         }
 688     }
 689     // Track the stub we have created so that it will be deleted later.
 690     stubInfo->stubRoutine = patchBuffer.finalizeCode();
 691
 692     // Finally patch the jump to slow case back in the hot path to jump here instead.
 693     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
 694     RepatchBuffer repatchBuffer(m_codeBlock);
 695     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubInfo->stubRoutine.code()));
 696
 697     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
 698     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_proto_list));
 699 }
 700
 701 void JIT::privateCompileGetByIdSelfList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* polymorphicStructures, int currentIndex, Structure* structure, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset)
 702 {
 703     Jump failureCase = checkStructure(regT0, structure);
 704     bool needsStubLink = false;
 705     bool isDirect = false;
 706     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 707         needsStubLink = true;
 708         compileGetDirectOffset(regT0, regT1, cachedOffset);
 709         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 710         stubCall.addArgument(regT1);
 711         stubCall.addArgument(regT0);
 712         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 713         stubCall.call();
 714     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 715         needsStubLink = true;
 716         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 717         stubCall.addArgument(regT0);
 718         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 719         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 720         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 721         stubCall.call();
 722     } else {
 723         isDirect = true;
 724         compileGetDirectOffset(regT0, regT0, cachedOffset);
 725     }
 726     Jump success = jump();
 727
 728     LinkBuffer patchBuffer(*m_globalData, this);
 729
 730     if (needsStubLink) {
 731         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 732             if (iter->to)
 733                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 734         }
 735     }
 736
 737     // Use the patch information to link the failure cases back to the original slow case routine.
 738     CodeLocationLabel lastProtoBegin = CodeLocationLabel(polymorphicStructures->list[currentIndex - 1].stubRoutine.code());
 739     if (!lastProtoBegin)
 740         lastProtoBegin = stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall);
 741
 742     patchBuffer.link(failureCase, lastProtoBegin);
 743
 744     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 745     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
 746
 747     MacroAssemblerCodeRef stubCode = patchBuffer.finalizeCode();
 748
 749     polymorphicStructures->list[currentIndex].set(*m_globalData, m_codeBlock->ownerExecutable(), stubCode, structure, isDirect);
 750
 751     // Finally patch the jump to slow case back in the hot path to jump here instead.
 752     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
 753     RepatchBuffer repatchBuffer(m_codeBlock);
 754     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubCode.code()));
 755 }
 756
 757 void JIT::privateCompileGetByIdProtoList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructures, int currentIndex, Structure* structure, Structure* prototypeStructure, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, CallFrame* callFrame)
 758 {
 759     // The prototype object definitely exists (if this stub exists the CodeBlock is referencing a Structure that is
 760     // referencing the prototype object - let's speculatively load it's table nice and early!)
 761     JSObject* protoObject = asObject(structure->prototypeForLookup(callFrame));
 762
 763     // Check eax is an object of the right Structure.
 764     Jump failureCases1 = checkStructure(regT0, structure);
 765
 766     // Check the prototype object's Structure had not changed.
 767     move(TrustedImmPtr(protoObject), regT3);
 768     Jump failureCases2 = branchPtr(NotEqual, Address(regT3, JSCell::structureOffset()), TrustedImmPtr(prototypeStructure));
 769
 770     // Checks out okay!
 771     bool needsStubLink = false;
 772     bool isDirect = false;
 773     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 774         needsStubLink = true;
 775         compileGetDirectOffset(protoObject, regT1, cachedOffset);
 776         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 777         stubCall.addArgument(regT1);
 778         stubCall.addArgument(regT0);
 779         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 780         stubCall.call();
 781     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 782         needsStubLink = true;
 783         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 784         stubCall.addArgument(TrustedImmPtr(protoObject));
 785         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 786         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 787         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 788         stubCall.call();
 789     } else {
 790         isDirect = true;
 791         compileGetDirectOffset(protoObject, regT0, cachedOffset);
 792     }
 793
 794     Jump success = jump();
 795
 796     LinkBuffer patchBuffer(*m_globalData, this);
 797
 798     if (needsStubLink) {
 799         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 800             if (iter->to)
 801                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 802         }
 803     }
 804
 805     // Use the patch information to link the failure cases back to the original slow case routine.
 806     CodeLocationLabel lastProtoBegin = CodeLocationLabel(prototypeStructures->list[currentIndex - 1].stubRoutine.code());
 807     patchBuffer.link(failureCases1, lastProtoBegin);
 808     patchBuffer.link(failureCases2, lastProtoBegin);
 809
 810     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 811     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
 812
 813     MacroAssemblerCodeRef stubCode = patchBuffer.finalizeCode();
 814     prototypeStructures->list[currentIndex].set(*m_globalData, m_codeBlock->ownerExecutable(), stubCode, structure, prototypeStructure, isDirect);
 815
 816     // Finally patch the jump to slow case back in the hot path to jump here instead.
 817     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
 818     RepatchBuffer repatchBuffer(m_codeBlock);
 819     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubCode.code()));
 820 }
 821
 822 void JIT::privateCompileGetByIdChainList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructures, int currentIndex, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, CallFrame* callFrame)
 823 {
 824     ASSERT(count);
 825     JumpList bucketsOfFail;
 826
 827     // Check eax is an object of the right Structure.
 828     Jump baseObjectCheck = checkStructure(regT0, structure);
 829     bucketsOfFail.append(baseObjectCheck);
 830
 831     Structure* currStructure = structure;
 832     WriteBarrier<Structure>* it = chain->head();
 833     JSObject* protoObject = 0;
 834     for (unsigned i = 0; i < count; ++i, ++it) {
 835         protoObject = asObject(currStructure->prototypeForLookup(callFrame));
 836         currStructure = it->get();
 837         testPrototype(protoObject, bucketsOfFail);
 838     }
 839     ASSERT(protoObject);
 840
 841     bool needsStubLink = false;
 842     bool isDirect = false;
 843     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 844         needsStubLink = true;
 845         compileGetDirectOffset(protoObject, regT1, cachedOffset);
 846         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 847         stubCall.addArgument(regT1);
 848         stubCall.addArgument(regT0);
 849         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 850         stubCall.call();
 851     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 852         needsStubLink = true;
 853         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 854         stubCall.addArgument(TrustedImmPtr(protoObject));
 855         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 856         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 857         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 858         stubCall.call();
 859     } else {
 860         isDirect = true;
 861         compileGetDirectOffset(protoObject, regT0, cachedOffset);
 862     }
 863     Jump success = jump();
 864
 865     LinkBuffer patchBuffer(*m_globalData, this);
 866
 867     if (needsStubLink) {
 868         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 869             if (iter->to)
 870                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 871         }
 872     }
 873
 874     // Use the patch information to link the failure cases back to the original slow case routine.
 875     CodeLocationLabel lastProtoBegin = CodeLocationLabel(prototypeStructures->list[currentIndex - 1].stubRoutine.code());
 876
 877     patchBuffer.link(bucketsOfFail, lastProtoBegin);
 878
 879     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 880     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
 881
 882     CodeRef stubRoutine = patchBuffer.finalizeCode();
 883
 884     // Track the stub we have created so that it will be deleted later.
 885     prototypeStructures->list[currentIndex].set(callFrame->globalData(), m_codeBlock->ownerExecutable(), stubRoutine, structure, chain, isDirect);
 886
 887     // Finally patch the jump to slow case back in the hot path to jump here instead.
 888     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
 889     RepatchBuffer repatchBuffer(m_codeBlock);
 890     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine.code()));
 891 }
 892
 893 void JIT::privateCompileGetByIdChain(StructureStubInfo* stubInfo, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, ReturnAddressPtr returnAddress, CallFrame* callFrame)
 894 {
 895     ASSERT(count);
 896
 897     JumpList bucketsOfFail;
 898
 899     // Check eax is an object of the right Structure.
 900     bucketsOfFail.append(checkStructure(regT0, structure));
 901
 902     Structure* currStructure = structure;
 903     WriteBarrier<Structure>* it = chain->head();
 904     JSObject* protoObject = 0;
 905     for (unsigned i = 0; i < count; ++i, ++it) {
 906         protoObject = asObject(currStructure->prototypeForLookup(callFrame));
 907         currStructure = it->get();
 908         testPrototype(protoObject, bucketsOfFail);
 909     }
 910     ASSERT(protoObject);
 911
 912     bool needsStubLink = false;
 913     if (slot.cachedPropertyType() == PropertySlot::Getter) {
 914         needsStubLink = true;
 915         compileGetDirectOffset(protoObject, regT1, cachedOffset);
 916         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
 917         stubCall.addArgument(regT1);
 918         stubCall.addArgument(regT0);
 919         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 920         stubCall.call();
 921     } else if (slot.cachedPropertyType() == PropertySlot::Custom) {
 922         needsStubLink = true;
 923         JITStubCall stubCall(this, cti_op_get_by_id_custom_stub);
 924         stubCall.addArgument(TrustedImmPtr(protoObject));
 925         stubCall.addArgument(TrustedImmPtr(FunctionPtr(slot.customGetter()).executableAddress()));
 926         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
 927         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
 928         stubCall.call();
 929     } else
 930         compileGetDirectOffset(protoObject, regT0, cachedOffset);
 931     Jump success = jump();
 932
 933     LinkBuffer patchBuffer(*m_globalData, this);
 934
 935     if (needsStubLink) {
 936         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
 937             if (iter->to)
 938                 patchBuffer.link(iter->from, FunctionPtr(iter->to));
 939         }
 940     }
 941
 942     // Use the patch information to link the failure cases back to the original slow case routine.
 943     patchBuffer.link(bucketsOfFail, stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall));
 944
 945     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
 946     patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
 947
 948     // Track the stub we have created so that it will be deleted later.
 949     CodeRef stubRoutine = patchBuffer.finalizeCode();
 950     stubInfo->stubRoutine = stubRoutine;
 951
 952     // Finally patch the jump to slow case back in the hot path to jump here instead.
 953     CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
 954     RepatchBuffer repatchBuffer(m_codeBlock);
 955     repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine.code()));
 956
 957     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
 958     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_proto_list));
 959 }
 960
 961 void JIT::emit_op_get_scoped_var(Instruction* currentInstruction)
 962 {
 963     int skip = currentInstruction[3].u.operand;
 964
 965     emitGetFromCallFrameHeaderPtr(RegisterFile::ScopeChain, regT0);
 966     bool checkTopLevel = m_codeBlock->codeType() == FunctionCode && m_codeBlock->needsFullScopeChain();
 967     ASSERT(skip || !checkTopLevel);
 968     if (checkTopLevel && skip--) {
 969         Jump activationNotCreated;
 970         if (checkTopLevel)
 971             activationNotCreated = branchTestPtr(Zero, addressFor(m_codeBlock->activationRegister()));
 972         loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
 973         activationNotCreated.link(this);
 974     }
 975     while (skip--)
 976         loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
 977
 978     loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, object)), regT0);
 979     loadPtr(Address(regT0, JSVariableObject::offsetOfRegisters()), regT0);
 980     loadPtr(Address(regT0, currentInstruction[2].u.operand * sizeof(Register)), regT0);
 981     emitValueProfilingSite(FirstProfilingSite);
 982     emitPutVirtualRegister(currentInstruction[1].u.operand);
 983 }
 984
 985 void JIT::emit_op_put_scoped_var(Instruction* currentInstruction)
 986 {
 987     int skip = currentInstruction[2].u.operand;
 988
 989     emitGetVirtualRegister(currentInstruction[3].u.operand, regT0);
 990
 991     emitGetFromCallFrameHeaderPtr(RegisterFile::ScopeChain, regT1);
 992     bool checkTopLevel = m_codeBlock->codeType() == FunctionCode && m_codeBlock->needsFullScopeChain();
 993     ASSERT(skip || !checkTopLevel);
 994     if (checkTopLevel && skip--) {
 995         Jump activationNotCreated;
 996         if (checkTopLevel)
 997             activationNotCreated = branchTestPtr(Zero, addressFor(m_codeBlock->activationRegister()));
 998         loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, next)), regT1);
 999         activationNotCreated.link(this);
1000     }
1001     while (skip--)
1002         loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, next)), regT1);
1003     loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, object)), regT1);
1004
1005     emitWriteBarrier(regT1, regT0, regT2, regT3, ShouldFilterImmediates, WriteBarrierForVariableAccess);
1006
1007     loadPtr(Address(regT1, JSVariableObject::offsetOfRegisters()), regT1);
1008     storePtr(regT0, Address(regT1, currentInstruction[1].u.operand * sizeof(Register)));
1009 }
1010
1011 void JIT::emit_op_get_global_var(Instruction* currentInstruction)
1012 {
1013     JSVariableObject* globalObject = m_codeBlock->globalObject();
1014     loadPtr(&globalObject->m_registers, regT0);
1015     loadPtr(Address(regT0, currentInstruction[2].u.operand * sizeof(Register)), regT0);
1016     emitValueProfilingSite(FirstProfilingSite);
1017     emitPutVirtualRegister(currentInstruction[1].u.operand);
1018 }
1019
1020 void JIT::emit_op_put_global_var(Instruction* currentInstruction)
1021 {
1022     JSGlobalObject* globalObject = m_codeBlock->globalObject();
1023
1024     emitGetVirtualRegister(currentInstruction[2].u.operand, regT0);
1025
1026     move(TrustedImmPtr(globalObject), regT1);
1027     loadPtr(Address(regT1, JSVariableObject::offsetOfRegisters()), regT1);
1028     storePtr(regT0, Address(regT1, currentInstruction[1].u.operand * sizeof(Register)));
1029     emitWriteBarrier(globalObject, regT0, regT2, ShouldFilterImmediates, WriteBarrierForVariableAccess);
1030 }
1031
1032 #endif // USE(JSVALUE64)
1033
1034 void JIT::emitWriteBarrier(RegisterID owner, RegisterID value, RegisterID scratch, RegisterID scratch2, WriteBarrierMode mode, WriteBarrierUseKind useKind)
1035 {
1036     UNUSED_PARAM(owner);
1037     UNUSED_PARAM(scratch);
1038     UNUSED_PARAM(scratch2);
1039     UNUSED_PARAM(useKind);
1040     UNUSED_PARAM(value);
1041     UNUSED_PARAM(mode);
1042     ASSERT(owner != scratch);
1043     ASSERT(owner != scratch2);
1044
1045 #if ENABLE(WRITE_BARRIER_PROFILING)
1046     emitCount(WriteBarrierCounters::jitCounterFor(useKind));
1047 #endif
1048
1049 #if ENABLE(GGC)
1050     Jump filterCells;
1051     if (mode == ShouldFilterImmediates)
1052         filterCells = emitJumpIfNotJSCell(value);
1053     move(owner, scratch);
1054     andPtr(TrustedImm32(static_cast<int32_t>(MarkedBlock::blockMask)), scratch);
1055     move(owner, scratch2);
1056     // consume additional 8 bits as we're using an approximate filter
1057     rshift32(TrustedImm32(MarkedBlock::atomShift + 8), scratch2);
1058     andPtr(TrustedImm32(MarkedBlock::atomMask >> 8), scratch2);
1059     Jump filter = branchTest8(Zero, BaseIndex(scratch, scratch2, TimesOne, MarkedBlock::offsetOfMarks()));
1060     move(owner, scratch2);
1061     rshift32(TrustedImm32(MarkedBlock::cardShift), scratch2);
1062     andPtr(TrustedImm32(MarkedBlock::cardMask), scratch2);
1063     store8(TrustedImm32(1), BaseIndex(scratch, scratch2, TimesOne, MarkedBlock::offsetOfCards()));
1064     filter.link(this);
1065     if (mode == ShouldFilterImmediates)
1066         filterCells.link(this);
1067 #endif
1068 }
1069
1070 void JIT::emitWriteBarrier(JSCell* owner, RegisterID value, RegisterID scratch, WriteBarrierMode mode, WriteBarrierUseKind useKind)
1071 {
1072     UNUSED_PARAM(owner);
1073     UNUSED_PARAM(scratch);
1074     UNUSED_PARAM(useKind);
1075     UNUSED_PARAM(value);
1076     UNUSED_PARAM(mode);
1077
1078 #if ENABLE(WRITE_BARRIER_PROFILING)
1079     emitCount(WriteBarrierCounters::jitCounterFor(useKind));
1080 #endif
1081
1082 #if ENABLE(GGC)
1083     Jump filterCells;
1084     if (mode == ShouldFilterImmediates)
1085         filterCells = emitJumpIfNotJSCell(value);
1086     uint8_t* cardAddress = Heap::addressOfCardFor(owner);
1087     move(TrustedImmPtr(cardAddress), scratch);
1088     store8(TrustedImm32(1), Address(scratch));
1089     if (mode == ShouldFilterImmediates)
1090         filterCells.link(this);
1091 #endif
1092 }
1093
1094 void JIT::testPrototype(JSValue prototype, JumpList& failureCases)
1095 {
1096     if (prototype.isNull())
1097         return;
1098
1099     ASSERT(prototype.isCell());
1100     move(TrustedImmPtr(prototype.asCell()), regT3);
1101     failureCases.append(branchPtr(NotEqual, Address(regT3, JSCell::structureOffset()), TrustedImmPtr(prototype.asCell()->structure())));
1102 }
1103
1104 void JIT::patchMethodCallProto(JSGlobalData& globalData, CodeBlock* codeBlock, MethodCallLinkInfo& methodCallLinkInfo, JSObject* callee, Structure* structure, JSObject* proto, ReturnAddressPtr returnAddress)
1105 {
1106     RepatchBuffer repatchBuffer(codeBlock);
1107
1108     CodeLocationDataLabelPtr structureLocation = methodCallLinkInfo.cachedStructure.location();
1109     methodCallLinkInfo.cachedStructure.set(globalData, structureLocation, codeBlock->ownerExecutable(), structure);
1110
1111     Structure* prototypeStructure = proto->structure();
1112     methodCallLinkInfo.cachedPrototypeStructure.set(globalData, structureLocation.dataLabelPtrAtOffset(patchOffsetMethodCheckProtoStruct), codeBlock->ownerExecutable(), prototypeStructure);
1113     methodCallLinkInfo.cachedPrototype.set(globalData, structureLocation.dataLabelPtrAtOffset(patchOffsetMethodCheckProtoObj), codeBlock->ownerExecutable(), proto);
1114     methodCallLinkInfo.cachedFunction.set(globalData, structureLocation.dataLabelPtrAtOffset(patchOffsetMethodCheckPutFunction), codeBlock->ownerExecutable(), callee);
1115     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_method_check_update));
1116 }
1117
1118 } // namespace JSC
1119
1120 #endif // ENABLE(JIT)