Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp

   1 /*
   2  * Copyright (C) 2011-2015 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "DFGSpeculativeJIT.h"
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "BinarySwitch.h"
  32 #include "DFGAbstractInterpreterInlines.h"
  33 #include "DFGArrayifySlowPathGenerator.h"
  34 #include "DFGCallArrayAllocatorSlowPathGenerator.h"
  35 #include "DFGCallCreateDirectArgumentsSlowPathGenerator.h"
  36 #include "DFGMayExit.h"
  37 #include "DFGOSRExitFuzz.h"
  38 #include "DFGSaneStringGetByValSlowPathGenerator.h"
  39 #include "DFGSlowPathGenerator.h"
  40 #include "DirectArguments.h"
  41 #include "JSArrowFunction.h"
  42 #include "JSCInlines.h"
  43 #include "JSEnvironmentRecord.h"
  44 #include "JSLexicalEnvironment.h"
  45 #include "LinkBuffer.h"
  46 #include "ScopedArguments.h"
  47 #include "ScratchRegisterAllocator.h"
  48 #include "WriteBarrierBuffer.h"
  49 #include <wtf/MathExtras.h>
  50
  51 namespace JSC { namespace DFG {
  52
  53 SpeculativeJIT::SpeculativeJIT(JITCompiler& jit)
  54     : m_compileOkay(true)
  55     , m_jit(jit)
  56     , m_currentNode(0)
  57     , m_lastGeneratedNode(LastNodeType)
  58     , m_indexInBlock(0)
  59     , m_generationInfo(m_jit.graph().frameRegisterCount())
  60     , m_state(m_jit.graph())
  61     , m_interpreter(m_jit.graph(), m_state)
  62     , m_stream(&jit.jitCode()->variableEventStream)
  63     , m_minifiedGraph(&jit.jitCode()->minifiedDFG)
  64 {
  65 }
  66
  67 SpeculativeJIT::~SpeculativeJIT()
  68 {
  69 }
  70
  71 void SpeculativeJIT::emitAllocateJSArray(GPRReg resultGPR, Structure* structure, GPRReg storageGPR, unsigned numElements)
  72 {
  73     ASSERT(hasUndecided(structure->indexingType()) || hasInt32(structure->indexingType()) || hasDouble(structure->indexingType()) || hasContiguous(structure->indexingType()));
  74
  75     GPRTemporary scratch(this);
  76     GPRTemporary scratch2(this);
  77     GPRReg scratchGPR = scratch.gpr();
  78     GPRReg scratch2GPR = scratch2.gpr();
  79
  80     unsigned vectorLength = std::max(BASE_VECTOR_LEN, numElements);
  81
  82     JITCompiler::JumpList slowCases;
  83
  84     slowCases.append(
  85         emitAllocateBasicStorage(TrustedImm32(vectorLength * sizeof(JSValue) + sizeof(IndexingHeader)), storageGPR));
  86     m_jit.subPtr(TrustedImm32(vectorLength * sizeof(JSValue)), storageGPR);
  87     emitAllocateJSObject<JSArray>(resultGPR, TrustedImmPtr(structure), storageGPR, scratchGPR, scratch2GPR, slowCases);
  88
  89     m_jit.store32(TrustedImm32(numElements), MacroAssembler::Address(storageGPR, Butterfly::offsetOfPublicLength()));
  90     m_jit.store32(TrustedImm32(vectorLength), MacroAssembler::Address(storageGPR, Butterfly::offsetOfVectorLength()));
  91
  92     if (hasDouble(structure->indexingType()) && numElements < vectorLength) {
  93 #if USE(JSVALUE64)
  94         m_jit.move(TrustedImm64(bitwise_cast<int64_t>(PNaN)), scratchGPR);
  95         for (unsigned i = numElements; i < vectorLength; ++i)
  96             m_jit.store64(scratchGPR, MacroAssembler::Address(storageGPR, sizeof(double) * i));
  97 #else
  98         EncodedValueDescriptor value;
  99         value.asInt64 = JSValue::encode(JSValue(JSValue::EncodeAsDouble, PNaN));
 100         for (unsigned i = numElements; i < vectorLength; ++i) {
 101             m_jit.store32(TrustedImm32(value.asBits.tag), MacroAssembler::Address(storageGPR, sizeof(double) * i + OBJECT_OFFSETOF(JSValue, u.asBits.tag)));
 102             m_jit.store32(TrustedImm32(value.asBits.payload), MacroAssembler::Address(storageGPR, sizeof(double) * i + OBJECT_OFFSETOF(JSValue, u.asBits.payload)));
 103         }
 104 #endif
 105     }
 106
 107     // I want a slow path that also loads out the storage pointer, and that's
 108     // what this custom CallArrayAllocatorSlowPathGenerator gives me. It's a lot
 109     // of work for a very small piece of functionality. :-/
 110     addSlowPathGenerator(std::make_unique<CallArrayAllocatorSlowPathGenerator>(
 111         slowCases, this, operationNewArrayWithSize, resultGPR, storageGPR,
 112         structure, numElements));
 113 }
 114
 115 void SpeculativeJIT::emitGetLength(InlineCallFrame* inlineCallFrame, GPRReg lengthGPR, bool includeThis)
 116 {
 117     if (inlineCallFrame && !inlineCallFrame->isVarargs())
 118         m_jit.move(TrustedImm32(inlineCallFrame->arguments.size() - !includeThis), lengthGPR);
 119     else {
 120         VirtualRegister argumentCountRegister;
 121         if (!inlineCallFrame)
 122             argumentCountRegister = VirtualRegister(JSStack::ArgumentCount);
 123         else
 124             argumentCountRegister = inlineCallFrame->argumentCountRegister;
 125         m_jit.load32(JITCompiler::payloadFor(argumentCountRegister), lengthGPR);
 126         if (!includeThis)
 127             m_jit.sub32(TrustedImm32(1), lengthGPR);
 128     }
 129 }
 130
 131 void SpeculativeJIT::emitGetLength(CodeOrigin origin, GPRReg lengthGPR, bool includeThis)
 132 {
 133     emitGetLength(origin.inlineCallFrame, lengthGPR, includeThis);
 134 }
 135
 136 void SpeculativeJIT::emitGetCallee(CodeOrigin origin, GPRReg calleeGPR)
 137 {
 138     if (origin.inlineCallFrame) {
 139         if (origin.inlineCallFrame->isClosureCall) {
 140             m_jit.loadPtr(
 141                 JITCompiler::addressFor(origin.inlineCallFrame->calleeRecovery.virtualRegister()),
 142                 calleeGPR);
 143         } else {
 144             m_jit.move(
 145                 TrustedImmPtr(origin.inlineCallFrame->calleeRecovery.constant().asCell()),
 146                 calleeGPR);
 147         }
 148     } else
 149         m_jit.loadPtr(JITCompiler::addressFor(JSStack::Callee), calleeGPR);
 150 }
 151
 152 void SpeculativeJIT::emitGetArgumentStart(CodeOrigin origin, GPRReg startGPR)
 153 {
 154     m_jit.addPtr(
 155         TrustedImm32(
 156             JITCompiler::argumentsStart(origin).offset() * static_cast<int>(sizeof(Register))),
 157         GPRInfo::callFrameRegister, startGPR);
 158 }
 159
 160 MacroAssembler::Jump SpeculativeJIT::emitOSRExitFuzzCheck()
 161 {
 162     if (!doOSRExitFuzzing())
 163         return MacroAssembler::Jump();
 164
 165     MacroAssembler::Jump result;
 166
 167     m_jit.pushToSave(GPRInfo::regT0);
 168     m_jit.load32(&g_numberOfOSRExitFuzzChecks, GPRInfo::regT0);
 169     m_jit.add32(TrustedImm32(1), GPRInfo::regT0);
 170     m_jit.store32(GPRInfo::regT0, &g_numberOfOSRExitFuzzChecks);
 171     unsigned atOrAfter = Options::fireOSRExitFuzzAtOrAfter();
 172     unsigned at = Options::fireOSRExitFuzzAt();
 173     if (at || atOrAfter) {
 174         unsigned threshold;
 175         MacroAssembler::RelationalCondition condition;
 176         if (atOrAfter) {
 177             threshold = atOrAfter;
 178             condition = MacroAssembler::Below;
 179         } else {
 180             threshold = at;
 181             condition = MacroAssembler::NotEqual;
 182         }
 183         MacroAssembler::Jump ok = m_jit.branch32(
 184             condition, GPRInfo::regT0, MacroAssembler::TrustedImm32(threshold));
 185         m_jit.popToRestore(GPRInfo::regT0);
 186         result = m_jit.jump();
 187         ok.link(&m_jit);
 188     }
 189     m_jit.popToRestore(GPRInfo::regT0);
 190
 191     return result;
 192 }
 193
 194 void SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Node* node, MacroAssembler::Jump jumpToFail)
 195 {
 196     if (!m_compileOkay)
 197         return;
 198     JITCompiler::Jump fuzzJump = emitOSRExitFuzzCheck();
 199     if (fuzzJump.isSet()) {
 200         JITCompiler::JumpList jumpsToFail;
 201         jumpsToFail.append(fuzzJump);
 202         jumpsToFail.append(jumpToFail);
 203         m_jit.appendExitInfo(jumpsToFail);
 204     } else
 205         m_jit.appendExitInfo(jumpToFail);
 206     m_jit.jitCode()->appendOSRExit(OSRExit(kind, jsValueSource, m_jit.graph().methodOfGettingAValueProfileFor(node), this, m_stream->size()));
 207 }
 208
 209 void SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Node* node, const MacroAssembler::JumpList& jumpsToFail)
 210 {
 211     if (!m_compileOkay)
 212         return;
 213     JITCompiler::Jump fuzzJump = emitOSRExitFuzzCheck();
 214     if (fuzzJump.isSet()) {
 215         JITCompiler::JumpList myJumpsToFail;
 216         myJumpsToFail.append(jumpsToFail);
 217         myJumpsToFail.append(fuzzJump);
 218         m_jit.appendExitInfo(myJumpsToFail);
 219     } else
 220         m_jit.appendExitInfo(jumpsToFail);
 221     m_jit.jitCode()->appendOSRExit(OSRExit(kind, jsValueSource, m_jit.graph().methodOfGettingAValueProfileFor(node), this, m_stream->size()));
 222 }
 223
 224 OSRExitJumpPlaceholder SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Node* node)
 225 {
 226     if (!m_compileOkay)
 227         return OSRExitJumpPlaceholder();
 228     unsigned index = m_jit.jitCode()->osrExit.size();
 229     m_jit.appendExitInfo();
 230     m_jit.jitCode()->appendOSRExit(OSRExit(kind, jsValueSource, m_jit.graph().methodOfGettingAValueProfileFor(node), this, m_stream->size()));
 231     return OSRExitJumpPlaceholder(index);
 232 }
 233
 234 OSRExitJumpPlaceholder SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Edge nodeUse)
 235 {
 236     return speculationCheck(kind, jsValueSource, nodeUse.node());
 237 }
 238
 239 void SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Edge nodeUse, MacroAssembler::Jump jumpToFail)
 240 {
 241     speculationCheck(kind, jsValueSource, nodeUse.node(), jumpToFail);
 242 }
 243
 244 void SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Edge nodeUse, const MacroAssembler::JumpList& jumpsToFail)
 245 {
 246     speculationCheck(kind, jsValueSource, nodeUse.node(), jumpsToFail);
 247 }
 248
 249 void SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Node* node, MacroAssembler::Jump jumpToFail, const SpeculationRecovery& recovery)
 250 {
 251     if (!m_compileOkay)
 252         return;
 253     unsigned recoveryIndex = m_jit.jitCode()->appendSpeculationRecovery(recovery);
 254     m_jit.appendExitInfo(jumpToFail);
 255     m_jit.jitCode()->appendOSRExit(OSRExit(kind, jsValueSource, m_jit.graph().methodOfGettingAValueProfileFor(node), this, m_stream->size(), recoveryIndex));
 256 }
 257
 258 void SpeculativeJIT::speculationCheck(ExitKind kind, JSValueSource jsValueSource, Edge nodeUse, MacroAssembler::Jump jumpToFail, const SpeculationRecovery& recovery)
 259 {
 260     speculationCheck(kind, jsValueSource, nodeUse.node(), jumpToFail, recovery);
 261 }
 262
 263 void SpeculativeJIT::emitInvalidationPoint(Node* node)
 264 {
 265     if (!m_compileOkay)
 266         return;
 267     OSRExitCompilationInfo& info = m_jit.appendExitInfo(JITCompiler::JumpList());
 268     m_jit.jitCode()->appendOSRExit(OSRExit(
 269         UncountableInvalidation, JSValueSource(),
 270         m_jit.graph().methodOfGettingAValueProfileFor(node),
 271         this, m_stream->size()));
 272     info.m_replacementSource = m_jit.watchpointLabel();
 273     ASSERT(info.m_replacementSource.isSet());
 274     noResult(node);
 275 }
 276
 277 void SpeculativeJIT::terminateSpeculativeExecution(ExitKind kind, JSValueRegs jsValueRegs, Node* node)
 278 {
 279     if (!m_compileOkay)
 280         return;
 281     speculationCheck(kind, jsValueRegs, node, m_jit.jump());
 282     m_compileOkay = false;
 283     if (verboseCompilationEnabled())
 284         dataLog("Bailing compilation.\n");
 285 }
 286
 287 void SpeculativeJIT::terminateSpeculativeExecution(ExitKind kind, JSValueRegs jsValueRegs, Edge nodeUse)
 288 {
 289     terminateSpeculativeExecution(kind, jsValueRegs, nodeUse.node());
 290 }
 291
 292 void SpeculativeJIT::typeCheck(JSValueSource source, Edge edge, SpeculatedType typesPassedThrough, MacroAssembler::Jump jumpToFail)
 293 {
 294     ASSERT(needsTypeCheck(edge, typesPassedThrough));
 295     m_interpreter.filter(edge, typesPassedThrough);
 296     speculationCheck(BadType, source, edge.node(), jumpToFail);
 297 }
 298
 299 RegisterSet SpeculativeJIT::usedRegisters()
 300 {
 301     RegisterSet result;
 302
 303     for (unsigned i = GPRInfo::numberOfRegisters; i--;) {
 304         GPRReg gpr = GPRInfo::toRegister(i);
 305         if (m_gprs.isInUse(gpr))
 306             result.set(gpr);
 307     }
 308     for (unsigned i = FPRInfo::numberOfRegisters; i--;) {
 309         FPRReg fpr = FPRInfo::toRegister(i);
 310         if (m_fprs.isInUse(fpr))
 311             result.set(fpr);
 312     }
 313
 314     result.merge(RegisterSet::stubUnavailableRegisters());
 315
 316     return result;
 317 }
 318
 319 void SpeculativeJIT::addSlowPathGenerator(std::unique_ptr<SlowPathGenerator> slowPathGenerator)
 320 {
 321     m_slowPathGenerators.append(WTF::move(slowPathGenerator));
 322 }
 323
 324 void SpeculativeJIT::runSlowPathGenerators()
 325 {
 326     for (unsigned i = 0; i < m_slowPathGenerators.size(); ++i)
 327         m_slowPathGenerators[i]->generate(this);
 328 }
 329
 330 // On Windows we need to wrap fmod; on other platforms we can call it directly.
 331 // On ARMv7 we assert that all function pointers have to low bit set (point to thumb code).
 332 #if CALLING_CONVENTION_IS_STDCALL || CPU(ARM_THUMB2)
 333 static double JIT_OPERATION fmodAsDFGOperation(double x, double y)
 334 {
 335     return fmod(x, y);
 336 }
 337 #else
 338 #define fmodAsDFGOperation fmod
 339 #endif
 340
 341 void SpeculativeJIT::clearGenerationInfo()
 342 {
 343     for (unsigned i = 0; i < m_generationInfo.size(); ++i)
 344         m_generationInfo[i] = GenerationInfo();
 345     m_gprs = RegisterBank<GPRInfo>();
 346     m_fprs = RegisterBank<FPRInfo>();
 347 }
 348
 349 SilentRegisterSavePlan SpeculativeJIT::silentSavePlanForGPR(VirtualRegister spillMe, GPRReg source)
 350 {
 351     GenerationInfo& info = generationInfoFromVirtualRegister(spillMe);
 352     Node* node = info.node();
 353     DataFormat registerFormat = info.registerFormat();
 354     ASSERT(registerFormat != DataFormatNone);
 355     ASSERT(registerFormat != DataFormatDouble);
 356
 357     SilentSpillAction spillAction;
 358     SilentFillAction fillAction;
 359
 360     if (!info.needsSpill())
 361         spillAction = DoNothingForSpill;
 362     else {
 363 #if USE(JSVALUE64)
 364         ASSERT(info.gpr() == source);
 365         if (registerFormat == DataFormatInt32)
 366             spillAction = Store32Payload;
 367         else if (registerFormat == DataFormatCell || registerFormat == DataFormatStorage)
 368             spillAction = StorePtr;
 369         else if (registerFormat == DataFormatInt52 || registerFormat == DataFormatStrictInt52)
 370             spillAction = Store64;
 371         else {
 372             ASSERT(registerFormat & DataFormatJS);
 373             spillAction = Store64;
 374         }
 375 #elif USE(JSVALUE32_64)
 376         if (registerFormat & DataFormatJS) {
 377             ASSERT(info.tagGPR() == source || info.payloadGPR() == source);
 378             spillAction = source == info.tagGPR() ? Store32Tag : Store32Payload;
 379         } else {
 380             ASSERT(info.gpr() == source);
 381             spillAction = Store32Payload;
 382         }
 383 #endif
 384     }
 385
 386     if (registerFormat == DataFormatInt32) {
 387         ASSERT(info.gpr() == source);
 388         ASSERT(isJSInt32(info.registerFormat()));
 389         if (node->hasConstant()) {
 390             ASSERT(node->isInt32Constant());
 391             fillAction = SetInt32Constant;
 392         } else
 393             fillAction = Load32Payload;
 394     } else if (registerFormat == DataFormatBoolean) {
 395 #if USE(JSVALUE64)
 396         RELEASE_ASSERT_NOT_REACHED();
 397 #if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
 398         fillAction = DoNothingForFill;
 399 #endif
 400 #elif USE(JSVALUE32_64)
 401         ASSERT(info.gpr() == source);
 402         if (node->hasConstant()) {
 403             ASSERT(node->isBooleanConstant());
 404             fillAction = SetBooleanConstant;
 405         } else
 406             fillAction = Load32Payload;
 407 #endif
 408     } else if (registerFormat == DataFormatCell) {
 409         ASSERT(info.gpr() == source);
 410         if (node->hasConstant()) {
 411             DFG_ASSERT(m_jit.graph(), m_currentNode, node->isCellConstant());
 412             node->asCell(); // To get the assertion.
 413             fillAction = SetCellConstant;
 414         } else {
 415 #if USE(JSVALUE64)
 416             fillAction = LoadPtr;
 417 #else
 418             fillAction = Load32Payload;
 419 #endif
 420         }
 421     } else if (registerFormat == DataFormatStorage) {
 422         ASSERT(info.gpr() == source);
 423         fillAction = LoadPtr;
 424     } else if (registerFormat == DataFormatInt52) {
 425         if (node->hasConstant())
 426             fillAction = SetInt52Constant;
 427         else if (info.spillFormat() == DataFormatInt52)
 428             fillAction = Load64;
 429         else if (info.spillFormat() == DataFormatStrictInt52)
 430             fillAction = Load64ShiftInt52Left;
 431         else if (info.spillFormat() == DataFormatNone)
 432             fillAction = Load64;
 433         else {
 434             RELEASE_ASSERT_NOT_REACHED();
 435 #if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
 436             fillAction = Load64; // Make GCC happy.
 437 #endif
 438         }
 439     } else if (registerFormat == DataFormatStrictInt52) {
 440         if (node->hasConstant())
 441             fillAction = SetStrictInt52Constant;
 442         else if (info.spillFormat() == DataFormatInt52)
 443             fillAction = Load64ShiftInt52Right;
 444         else if (info.spillFormat() == DataFormatStrictInt52)
 445             fillAction = Load64;
 446         else if (info.spillFormat() == DataFormatNone)
 447             fillAction = Load64;
 448         else {
 449             RELEASE_ASSERT_NOT_REACHED();
 450 #if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
 451             fillAction = Load64; // Make GCC happy.
 452 #endif
 453         }
 454     } else {
 455         ASSERT(registerFormat & DataFormatJS);
 456 #if USE(JSVALUE64)
 457         ASSERT(info.gpr() == source);
 458         if (node->hasConstant()) {
 459             if (node->isCellConstant())
 460                 fillAction = SetTrustedJSConstant;
 461             else
 462                 fillAction = SetJSConstant;
 463         } else if (info.spillFormat() == DataFormatInt32) {
 464             ASSERT(registerFormat == DataFormatJSInt32);
 465             fillAction = Load32PayloadBoxInt;
 466         } else
 467             fillAction = Load64;
 468 #else
 469         ASSERT(info.tagGPR() == source || info.payloadGPR() == source);
 470         if (node->hasConstant())
 471             fillAction = info.tagGPR() == source ? SetJSConstantTag : SetJSConstantPayload;
 472         else if (info.payloadGPR() == source)
 473             fillAction = Load32Payload;
 474         else { // Fill the Tag
 475             switch (info.spillFormat()) {
 476             case DataFormatInt32:
 477                 ASSERT(registerFormat == DataFormatJSInt32);
 478                 fillAction = SetInt32Tag;
 479                 break;
 480             case DataFormatCell:
 481                 ASSERT(registerFormat == DataFormatJSCell);
 482                 fillAction = SetCellTag;
 483                 break;
 484             case DataFormatBoolean:
 485                 ASSERT(registerFormat == DataFormatJSBoolean);
 486                 fillAction = SetBooleanTag;
 487                 break;
 488             default:
 489                 fillAction = Load32Tag;
 490                 break;
 491             }
 492         }
 493 #endif
 494     }
 495
 496     return SilentRegisterSavePlan(spillAction, fillAction, node, source);
 497 }
 498
 499 SilentRegisterSavePlan SpeculativeJIT::silentSavePlanForFPR(VirtualRegister spillMe, FPRReg source)
 500 {
 501     GenerationInfo& info = generationInfoFromVirtualRegister(spillMe);
 502     Node* node = info.node();
 503     ASSERT(info.registerFormat() == DataFormatDouble);
 504
 505     SilentSpillAction spillAction;
 506     SilentFillAction fillAction;
 507
 508     if (!info.needsSpill())
 509         spillAction = DoNothingForSpill;
 510     else {
 511         ASSERT(!node->hasConstant());
 512         ASSERT(info.spillFormat() == DataFormatNone);
 513         ASSERT(info.fpr() == source);
 514         spillAction = StoreDouble;
 515     }
 516
 517 #if USE(JSVALUE64)
 518     if (node->hasConstant()) {
 519         node->asNumber(); // To get the assertion.
 520         fillAction = SetDoubleConstant;
 521     } else {
 522         ASSERT(info.spillFormat() == DataFormatNone || info.spillFormat() == DataFormatDouble);
 523         fillAction = LoadDouble;
 524     }
 525 #elif USE(JSVALUE32_64)
 526     ASSERT(info.registerFormat() == DataFormatDouble);
 527     if (node->hasConstant()) {
 528         node->asNumber(); // To get the assertion.
 529         fillAction = SetDoubleConstant;
 530     } else
 531         fillAction = LoadDouble;
 532 #endif
 533
 534     return SilentRegisterSavePlan(spillAction, fillAction, node, source);
 535 }
 536
 537 void SpeculativeJIT::silentSpill(const SilentRegisterSavePlan& plan)
 538 {
 539     switch (plan.spillAction()) {
 540     case DoNothingForSpill:
 541         break;
 542     case Store32Tag:
 543         m_jit.store32(plan.gpr(), JITCompiler::tagFor(plan.node()->virtualRegister()));
 544         break;
 545     case Store32Payload:
 546         m_jit.store32(plan.gpr(), JITCompiler::payloadFor(plan.node()->virtualRegister()));
 547         break;
 548     case StorePtr:
 549         m_jit.storePtr(plan.gpr(), JITCompiler::addressFor(plan.node()->virtualRegister()));
 550         break;
 551 #if USE(JSVALUE64)
 552     case Store64:
 553         m_jit.store64(plan.gpr(), JITCompiler::addressFor(plan.node()->virtualRegister()));
 554         break;
 555 #endif
 556     case StoreDouble:
 557         m_jit.storeDouble(plan.fpr(), JITCompiler::addressFor(plan.node()->virtualRegister()));
 558         break;
 559     default:
 560         RELEASE_ASSERT_NOT_REACHED();
 561     }
 562 }
 563
 564 void SpeculativeJIT::silentFill(const SilentRegisterSavePlan& plan, GPRReg canTrample)
 565 {
 566 #if USE(JSVALUE32_64)
 567     UNUSED_PARAM(canTrample);
 568 #endif
 569     switch (plan.fillAction()) {
 570     case DoNothingForFill:
 571         break;
 572     case SetInt32Constant:
 573         m_jit.move(Imm32(plan.node()->asInt32()), plan.gpr());
 574         break;
 575 #if USE(JSVALUE64)
 576     case SetInt52Constant:
 577         m_jit.move(Imm64(plan.node()->asMachineInt() << JSValue::int52ShiftAmount), plan.gpr());
 578         break;
 579     case SetStrictInt52Constant:
 580         m_jit.move(Imm64(plan.node()->asMachineInt()), plan.gpr());
 581         break;
 582 #endif // USE(JSVALUE64)
 583     case SetBooleanConstant:
 584         m_jit.move(TrustedImm32(plan.node()->asBoolean()), plan.gpr());
 585         break;
 586     case SetCellConstant:
 587         m_jit.move(TrustedImmPtr(plan.node()->asCell()), plan.gpr());
 588         break;
 589 #if USE(JSVALUE64)
 590     case SetTrustedJSConstant:
 591         m_jit.move(valueOfJSConstantAsImm64(plan.node()).asTrustedImm64(), plan.gpr());
 592         break;
 593     case SetJSConstant:
 594         m_jit.move(valueOfJSConstantAsImm64(plan.node()), plan.gpr());
 595         break;
 596     case SetDoubleConstant:
 597         m_jit.move(Imm64(reinterpretDoubleToInt64(plan.node()->asNumber())), canTrample);
 598         m_jit.move64ToDouble(canTrample, plan.fpr());
 599         break;
 600     case Load32PayloadBoxInt:
 601         m_jit.load32(JITCompiler::payloadFor(plan.node()->virtualRegister()), plan.gpr());
 602         m_jit.or64(GPRInfo::tagTypeNumberRegister, plan.gpr());
 603         break;
 604     case Load32PayloadConvertToInt52:
 605         m_jit.load32(JITCompiler::payloadFor(plan.node()->virtualRegister()), plan.gpr());
 606         m_jit.signExtend32ToPtr(plan.gpr(), plan.gpr());
 607         m_jit.lshift64(TrustedImm32(JSValue::int52ShiftAmount), plan.gpr());
 608         break;
 609     case Load32PayloadSignExtend:
 610         m_jit.load32(JITCompiler::payloadFor(plan.node()->virtualRegister()), plan.gpr());
 611         m_jit.signExtend32ToPtr(plan.gpr(), plan.gpr());
 612         break;
 613 #else
 614     case SetJSConstantTag:
 615         m_jit.move(Imm32(plan.node()->asJSValue().tag()), plan.gpr());
 616         break;
 617     case SetJSConstantPayload:
 618         m_jit.move(Imm32(plan.node()->asJSValue().payload()), plan.gpr());
 619         break;
 620     case SetInt32Tag:
 621         m_jit.move(TrustedImm32(JSValue::Int32Tag), plan.gpr());
 622         break;
 623     case SetCellTag:
 624         m_jit.move(TrustedImm32(JSValue::CellTag), plan.gpr());
 625         break;
 626     case SetBooleanTag:
 627         m_jit.move(TrustedImm32(JSValue::BooleanTag), plan.gpr());
 628         break;
 629     case SetDoubleConstant:
 630         m_jit.loadDouble(TrustedImmPtr(m_jit.addressOfDoubleConstant(plan.node())), plan.fpr());
 631         break;
 632 #endif
 633     case Load32Tag:
 634         m_jit.load32(JITCompiler::tagFor(plan.node()->virtualRegister()), plan.gpr());
 635         break;
 636     case Load32Payload:
 637         m_jit.load32(JITCompiler::payloadFor(plan.node()->virtualRegister()), plan.gpr());
 638         break;
 639     case LoadPtr:
 640         m_jit.loadPtr(JITCompiler::addressFor(plan.node()->virtualRegister()), plan.gpr());
 641         break;
 642 #if USE(JSVALUE64)
 643     case Load64:
 644         m_jit.load64(JITCompiler::addressFor(plan.node()->virtualRegister()), plan.gpr());
 645         break;
 646     case Load64ShiftInt52Right:
 647         m_jit.load64(JITCompiler::addressFor(plan.node()->virtualRegister()), plan.gpr());
 648         m_jit.rshift64(TrustedImm32(JSValue::int52ShiftAmount), plan.gpr());
 649         break;
 650     case Load64ShiftInt52Left:
 651         m_jit.load64(JITCompiler::addressFor(plan.node()->virtualRegister()), plan.gpr());
 652         m_jit.lshift64(TrustedImm32(JSValue::int52ShiftAmount), plan.gpr());
 653         break;
 654 #endif
 655     case LoadDouble:
 656         m_jit.loadDouble(JITCompiler::addressFor(plan.node()->virtualRegister()), plan.fpr());
 657         break;
 658     default:
 659         RELEASE_ASSERT_NOT_REACHED();
 660     }
 661 }
 662
 663 JITCompiler::Jump SpeculativeJIT::jumpSlowForUnwantedArrayMode(GPRReg tempGPR, ArrayMode arrayMode, IndexingType shape)
 664 {
 665     switch (arrayMode.arrayClass()) {
 666     case Array::OriginalArray: {
 667         CRASH();
 668 #if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
 669         JITCompiler::Jump result; // I already know that VC++ takes unkindly to the expression "return Jump()", so I'm doing it this way in anticipation of someone eventually using VC++ to compile the DFG.
 670         return result;
 671 #endif
 672     }
 673
 674     case Array::Array:
 675         m_jit.and32(TrustedImm32(IsArray | IndexingShapeMask), tempGPR);
 676         return m_jit.branch32(
 677             MacroAssembler::NotEqual, tempGPR, TrustedImm32(IsArray | shape));
 678
 679     case Array::NonArray:
 680     case Array::OriginalNonArray:
 681         m_jit.and32(TrustedImm32(IsArray | IndexingShapeMask), tempGPR);
 682         return m_jit.branch32(
 683             MacroAssembler::NotEqual, tempGPR, TrustedImm32(shape));
 684
 685     case Array::PossiblyArray:
 686         m_jit.and32(TrustedImm32(IndexingShapeMask), tempGPR);
 687         return m_jit.branch32(MacroAssembler::NotEqual, tempGPR, TrustedImm32(shape));
 688     }
 689
 690     RELEASE_ASSERT_NOT_REACHED();
 691     return JITCompiler::Jump();
 692 }
 693
 694 JITCompiler::JumpList SpeculativeJIT::jumpSlowForUnwantedArrayMode(GPRReg tempGPR, ArrayMode arrayMode)
 695 {
 696     JITCompiler::JumpList result;
 697
 698     switch (arrayMode.type()) {
 699     case Array::Int32:
 700         return jumpSlowForUnwantedArrayMode(tempGPR, arrayMode, Int32Shape);
 701
 702     case Array::Double:
 703         return jumpSlowForUnwantedArrayMode(tempGPR, arrayMode, DoubleShape);
 704
 705     case Array::Contiguous:
 706         return jumpSlowForUnwantedArrayMode(tempGPR, arrayMode, ContiguousShape);
 707
 708     case Array::Undecided:
 709         return jumpSlowForUnwantedArrayMode(tempGPR, arrayMode, UndecidedShape);
 710
 711     case Array::ArrayStorage:
 712     case Array::SlowPutArrayStorage: {
 713         ASSERT(!arrayMode.isJSArrayWithOriginalStructure());
 714
 715         if (arrayMode.isJSArray()) {
 716             if (arrayMode.isSlowPut()) {
 717                 result.append(
 718                     m_jit.branchTest32(
 719                         MacroAssembler::Zero, tempGPR, MacroAssembler::TrustedImm32(IsArray)));
 720                 m_jit.and32(TrustedImm32(IndexingShapeMask), tempGPR);
 721                 m_jit.sub32(TrustedImm32(ArrayStorageShape), tempGPR);
 722                 result.append(
 723                     m_jit.branch32(
 724                         MacroAssembler::Above, tempGPR,
 725                         TrustedImm32(SlowPutArrayStorageShape - ArrayStorageShape)));
 726                 break;
 727             }
 728             m_jit.and32(TrustedImm32(IsArray | IndexingShapeMask), tempGPR);
 729             result.append(
 730                 m_jit.branch32(MacroAssembler::NotEqual, tempGPR, TrustedImm32(IsArray | ArrayStorageShape)));
 731             break;
 732         }
 733         m_jit.and32(TrustedImm32(IndexingShapeMask), tempGPR);
 734         if (arrayMode.isSlowPut()) {
 735             m_jit.sub32(TrustedImm32(ArrayStorageShape), tempGPR);
 736             result.append(
 737                 m_jit.branch32(
 738                     MacroAssembler::Above, tempGPR,
 739                     TrustedImm32(SlowPutArrayStorageShape - ArrayStorageShape)));
 740             break;
 741         }
 742         result.append(
 743             m_jit.branch32(MacroAssembler::NotEqual, tempGPR, TrustedImm32(ArrayStorageShape)));
 744         break;
 745     }
 746     default:
 747         CRASH();
 748         break;
 749     }
 750
 751     return result;
 752 }
 753
 754 void SpeculativeJIT::checkArray(Node* node)
 755 {
 756     ASSERT(node->arrayMode().isSpecific());
 757     ASSERT(!node->arrayMode().doesConversion());
 758
 759     SpeculateCellOperand base(this, node->child1());
 760     GPRReg baseReg = base.gpr();
 761
 762     if (node->arrayMode().alreadyChecked(m_jit.graph(), node, m_state.forNode(node->child1()))) {
 763         noResult(m_currentNode);
 764         return;
 765     }
 766
 767     const ClassInfo* expectedClassInfo = 0;
 768
 769     switch (node->arrayMode().type()) {
 770     case Array::String:
 771         RELEASE_ASSERT_NOT_REACHED(); // Should have been a Phantom(String:)
 772         break;
 773     case Array::Int32:
 774     case Array::Double:
 775     case Array::Contiguous:
 776     case Array::Undecided:
 777     case Array::ArrayStorage:
 778     case Array::SlowPutArrayStorage: {
 779         GPRTemporary temp(this);
 780         GPRReg tempGPR = temp.gpr();
 781         m_jit.load8(MacroAssembler::Address(baseReg, JSCell::indexingTypeOffset()), tempGPR);
 782         speculationCheck(
 783             BadIndexingType, JSValueSource::unboxedCell(baseReg), 0,
 784             jumpSlowForUnwantedArrayMode(tempGPR, node->arrayMode()));
 785
 786         noResult(m_currentNode);
 787         return;
 788     }
 789     case Array::DirectArguments:
 790         speculateCellTypeWithoutTypeFiltering(node->child1(), baseReg, DirectArgumentsType);
 791         noResult(m_currentNode);
 792         return;
 793     case Array::ScopedArguments:
 794         speculateCellTypeWithoutTypeFiltering(node->child1(), baseReg, ScopedArgumentsType);
 795         noResult(m_currentNode);
 796         return;
 797     default:
 798         speculateCellTypeWithoutTypeFiltering(
 799             node->child1(), baseReg,
 800             typeForTypedArrayType(node->arrayMode().typedArrayType()));
 801         noResult(m_currentNode);
 802         return;
 803     }
 804
 805     RELEASE_ASSERT(expectedClassInfo);
 806
 807     GPRTemporary temp(this);
 808     GPRTemporary temp2(this);
 809     m_jit.emitLoadStructure(baseReg, temp.gpr(), temp2.gpr());
 810     speculationCheck(
 811         BadType, JSValueSource::unboxedCell(baseReg), node,
 812         m_jit.branchPtr(
 813             MacroAssembler::NotEqual,
 814             MacroAssembler::Address(temp.gpr(), Structure::classInfoOffset()),
 815             MacroAssembler::TrustedImmPtr(expectedClassInfo)));
 816
 817     noResult(m_currentNode);
 818 }
 819
 820 void SpeculativeJIT::arrayify(Node* node, GPRReg baseReg, GPRReg propertyReg)
 821 {
 822     ASSERT(node->arrayMode().doesConversion());
 823
 824     GPRTemporary temp(this);
 825     GPRTemporary structure;
 826     GPRReg tempGPR = temp.gpr();
 827     GPRReg structureGPR = InvalidGPRReg;
 828
 829     if (node->op() != ArrayifyToStructure) {
 830         GPRTemporary realStructure(this);
 831         structure.adopt(realStructure);
 832         structureGPR = structure.gpr();
 833     }
 834
 835     // We can skip all that comes next if we already have array storage.
 836     MacroAssembler::JumpList slowPath;
 837
 838     if (node->op() == ArrayifyToStructure) {
 839         slowPath.append(m_jit.branchWeakStructure(
 840             JITCompiler::NotEqual,
 841             JITCompiler::Address(baseReg, JSCell::structureIDOffset()),
 842             node->structure()));
 843     } else {
 844         m_jit.load8(
 845             MacroAssembler::Address(baseReg, JSCell::indexingTypeOffset()), tempGPR);
 846
 847         slowPath.append(jumpSlowForUnwantedArrayMode(tempGPR, node->arrayMode()));
 848     }
 849
 850     addSlowPathGenerator(std::make_unique<ArrayifySlowPathGenerator>(
 851         slowPath, this, node, baseReg, propertyReg, tempGPR, structureGPR));
 852
 853     noResult(m_currentNode);
 854 }
 855
 856 void SpeculativeJIT::arrayify(Node* node)
 857 {
 858     ASSERT(node->arrayMode().isSpecific());
 859
 860     SpeculateCellOperand base(this, node->child1());
 861
 862     if (!node->child2()) {
 863         arrayify(node, base.gpr(), InvalidGPRReg);
 864         return;
 865     }
 866
 867     SpeculateInt32Operand property(this, node->child2());
 868
 869     arrayify(node, base.gpr(), property.gpr());
 870 }
 871
 872 GPRReg SpeculativeJIT::fillStorage(Edge edge)
 873 {
 874     VirtualRegister virtualRegister = edge->virtualRegister();
 875     GenerationInfo& info = generationInfoFromVirtualRegister(virtualRegister);
 876
 877     switch (info.registerFormat()) {
 878     case DataFormatNone: {
 879         if (info.spillFormat() == DataFormatStorage) {
 880             GPRReg gpr = allocate();
 881             m_gprs.retain(gpr, virtualRegister, SpillOrderSpilled);
 882             m_jit.loadPtr(JITCompiler::addressFor(virtualRegister), gpr);
 883             info.fillStorage(*m_stream, gpr);
 884             return gpr;
 885         }
 886
 887         // Must be a cell; fill it as a cell and then return the pointer.
 888         return fillSpeculateCell(edge);
 889     }
 890
 891     case DataFormatStorage: {
 892         GPRReg gpr = info.gpr();
 893         m_gprs.lock(gpr);
 894         return gpr;
 895     }
 896
 897     default:
 898         return fillSpeculateCell(edge);
 899     }
 900 }
 901
 902 void SpeculativeJIT::useChildren(Node* node)
 903 {
 904     if (node->flags() & NodeHasVarArgs) {
 905         for (unsigned childIdx = node->firstChild(); childIdx < node->firstChild() + node->numChildren(); childIdx++) {
 906             if (!!m_jit.graph().m_varArgChildren[childIdx])
 907                 use(m_jit.graph().m_varArgChildren[childIdx]);
 908         }
 909     } else {
 910         Edge child1 = node->child1();
 911         if (!child1) {
 912             ASSERT(!node->child2() && !node->child3());
 913             return;
 914         }
 915         use(child1);
 916
 917         Edge child2 = node->child2();
 918         if (!child2) {
 919             ASSERT(!node->child3());
 920             return;
 921         }
 922         use(child2);
 923
 924         Edge child3 = node->child3();
 925         if (!child3)
 926             return;
 927         use(child3);
 928     }
 929 }
 930
 931 void SpeculativeJIT::compileIn(Node* node)
 932 {
 933     SpeculateCellOperand base(this, node->child2());
 934     GPRReg baseGPR = base.gpr();
 935
 936     if (JSString* string = node->child1()->dynamicCastConstant<JSString*>()) {
 937         if (string->tryGetValueImpl() && string->tryGetValueImpl()->isAtomic()) {
 938             StructureStubInfo* stubInfo = m_jit.codeBlock()->addStubInfo(AccessType::In);
 939
 940             GPRTemporary result(this);
 941             GPRReg resultGPR = result.gpr();
 942
 943             use(node->child1());
 944
 945             MacroAssembler::PatchableJump jump = m_jit.patchableJump();
 946             MacroAssembler::Label done = m_jit.label();
 947
 948             // Since this block is executed only when the result of string->tryGetValueImpl() is atomic,
 949             // we can cast it to const AtomicStringImpl* safely.
 950             auto slowPath = slowPathCall(
 951                 jump.m_jump, this, operationInOptimize,
 952                 JSValueRegs::payloadOnly(resultGPR), stubInfo, baseGPR,
 953                 static_cast<const AtomicStringImpl*>(string->tryGetValueImpl()));
 954
 955             stubInfo->callSiteIndex = m_jit.addCallSite(node->origin.semantic);
 956             stubInfo->codeOrigin = node->origin.semantic;
 957             stubInfo->patch.baseGPR = static_cast<int8_t>(baseGPR);
 958             stubInfo->patch.valueGPR = static_cast<int8_t>(resultGPR);
 959 #if USE(JSVALUE32_64)
 960             stubInfo->patch.valueTagGPR = static_cast<int8_t>(InvalidGPRReg);
 961 #endif
 962             stubInfo->patch.usedRegisters = usedRegisters();
 963             stubInfo->patch.spillMode = NeedToSpill;
 964
 965             m_jit.addIn(InRecord(jump, done, slowPath.get(), stubInfo));
 966             addSlowPathGenerator(WTF::move(slowPath));
 967
 968             base.use();
 969
 970             blessedBooleanResult(resultGPR, node, UseChildrenCalledExplicitly);
 971             return;
 972         }
 973     }
 974
 975     JSValueOperand key(this, node->child1());
 976     JSValueRegs regs = key.jsValueRegs();
 977
 978     GPRFlushedCallResult result(this);
 979     GPRReg resultGPR = result.gpr();
 980
 981     base.use();
 982     key.use();
 983
 984     flushRegisters();
 985     callOperation(
 986         operationGenericIn, extractResult(JSValueRegs::payloadOnly(resultGPR)),
 987         baseGPR, regs);
 988     m_jit.exceptionCheck();
 989     blessedBooleanResult(resultGPR, node, UseChildrenCalledExplicitly);
 990 }
 991
 992 bool SpeculativeJIT::nonSpeculativeCompare(Node* node, MacroAssembler::RelationalCondition cond, S_JITOperation_EJJ helperFunction)
 993 {
 994     unsigned branchIndexInBlock = detectPeepHoleBranch();
 995     if (branchIndexInBlock != UINT_MAX) {
 996         Node* branchNode = m_block->at(branchIndexInBlock);
 997
 998         ASSERT(node->adjustedRefCount() == 1);
 999
1000         nonSpeculativePeepholeBranch(node, branchNode, cond, helperFunction);
1001
1002         m_indexInBlock = branchIndexInBlock;
1003         m_currentNode = branchNode;
1004
1005         return true;
1006     }
1007
1008     nonSpeculativeNonPeepholeCompare(node, cond, helperFunction);
1009
1010     return false;
1011 }
1012
1013 bool SpeculativeJIT::nonSpeculativeStrictEq(Node* node, bool invert)
1014 {
1015     unsigned branchIndexInBlock = detectPeepHoleBranch();
1016     if (branchIndexInBlock != UINT_MAX) {
1017         Node* branchNode = m_block->at(branchIndexInBlock);
1018
1019         ASSERT(node->adjustedRefCount() == 1);
1020
1021         nonSpeculativePeepholeStrictEq(node, branchNode, invert);
1022
1023         m_indexInBlock = branchIndexInBlock;
1024         m_currentNode = branchNode;
1025
1026         return true;
1027     }
1028
1029     nonSpeculativeNonPeepholeStrictEq(node, invert);
1030
1031     return false;
1032 }
1033
1034 static const char* dataFormatString(DataFormat format)
1035 {
1036     // These values correspond to the DataFormat enum.
1037     const char* strings[] = {
1038         "[  ]",
1039         "[ i]",
1040         "[ d]",
1041         "[ c]",
1042         "Err!",
1043         "Err!",
1044         "Err!",
1045         "Err!",
1046         "[J ]",
1047         "[Ji]",
1048         "[Jd]",
1049         "[Jc]",
1050         "Err!",
1051         "Err!",
1052         "Err!",
1053         "Err!",
1054     };
1055     return strings[format];
1056 }
1057
1058 void SpeculativeJIT::dump(const char* label)
1059 {
1060     if (label)
1061         dataLogF("<%s>\n", label);
1062
1063     dataLogF("  gprs:\n");
1064     m_gprs.dump();
1065     dataLogF("  fprs:\n");
1066     m_fprs.dump();
1067     dataLogF("  VirtualRegisters:\n");
1068     for (unsigned i = 0; i < m_generationInfo.size(); ++i) {
1069         GenerationInfo& info = m_generationInfo[i];
1070         if (info.alive())
1071             dataLogF("    % 3d:%s%s", i, dataFormatString(info.registerFormat()), dataFormatString(info.spillFormat()));
1072         else
1073             dataLogF("    % 3d:[__][__]", i);
1074         if (info.registerFormat() == DataFormatDouble)
1075             dataLogF(":fpr%d\n", info.fpr());
1076         else if (info.registerFormat() != DataFormatNone
1077 #if USE(JSVALUE32_64)
1078             && !(info.registerFormat() & DataFormatJS)
1079 #endif
1080             ) {
1081             ASSERT(info.gpr() != InvalidGPRReg);
1082             dataLogF(":%s\n", GPRInfo::debugName(info.gpr()));
1083         } else
1084             dataLogF("\n");
1085     }
1086     if (label)
1087         dataLogF("</%s>\n", label);
1088 }
1089
1090 GPRTemporary::GPRTemporary()
1091     : m_jit(0)
1092     , m_gpr(InvalidGPRReg)
1093 {
1094 }
1095
1096 GPRTemporary::GPRTemporary(SpeculativeJIT* jit)
1097     : m_jit(jit)
1098     , m_gpr(InvalidGPRReg)
1099 {
1100     m_gpr = m_jit->allocate();
1101 }
1102
1103 GPRTemporary::GPRTemporary(SpeculativeJIT* jit, GPRReg specific)
1104     : m_jit(jit)
1105     , m_gpr(InvalidGPRReg)
1106 {
1107     m_gpr = m_jit->allocate(specific);
1108 }
1109
1110 #if USE(JSVALUE32_64)
1111 GPRTemporary::GPRTemporary(
1112     SpeculativeJIT* jit, ReuseTag, JSValueOperand& op1, WhichValueWord which)
1113     : m_jit(jit)
1114     , m_gpr(InvalidGPRReg)
1115 {
1116     if (!op1.isDouble() && m_jit->canReuse(op1.node()))
1117         m_gpr = m_jit->reuse(op1.gpr(which));
1118     else
1119         m_gpr = m_jit->allocate();
1120 }
1121 #endif // USE(JSVALUE32_64)
1122
1123 JSValueRegsTemporary::JSValueRegsTemporary() { }
1124
1125 JSValueRegsTemporary::JSValueRegsTemporary(SpeculativeJIT* jit)
1126 #if USE(JSVALUE64)
1127     : m_gpr(jit)
1128 #else
1129     : m_payloadGPR(jit)
1130     , m_tagGPR(jit)
1131 #endif
1132 {
1133 }
1134
1135 JSValueRegsTemporary::~JSValueRegsTemporary() { }
1136
1137 JSValueRegs JSValueRegsTemporary::regs()
1138 {
1139 #if USE(JSVALUE64)
1140     return JSValueRegs(m_gpr.gpr());
1141 #else
1142     return JSValueRegs(m_tagGPR.gpr(), m_payloadGPR.gpr());
1143 #endif
1144 }
1145
1146 void GPRTemporary::adopt(GPRTemporary& other)
1147 {
1148     ASSERT(!m_jit);
1149     ASSERT(m_gpr == InvalidGPRReg);
1150     ASSERT(other.m_jit);
1151     ASSERT(other.m_gpr != InvalidGPRReg);
1152     m_jit = other.m_jit;
1153     m_gpr = other.m_gpr;
1154     other.m_jit = 0;
1155     other.m_gpr = InvalidGPRReg;
1156 }
1157
1158 FPRTemporary::FPRTemporary(SpeculativeJIT* jit)
1159     : m_jit(jit)
1160     , m_fpr(InvalidFPRReg)
1161 {
1162     m_fpr = m_jit->fprAllocate();
1163 }
1164
1165 FPRTemporary::FPRTemporary(SpeculativeJIT* jit, SpeculateDoubleOperand& op1)
1166     : m_jit(jit)
1167     , m_fpr(InvalidFPRReg)
1168 {
1169     if (m_jit->canReuse(op1.node()))
1170         m_fpr = m_jit->reuse(op1.fpr());
1171     else
1172         m_fpr = m_jit->fprAllocate();
1173 }
1174
1175 FPRTemporary::FPRTemporary(SpeculativeJIT* jit, SpeculateDoubleOperand& op1, SpeculateDoubleOperand& op2)
1176     : m_jit(jit)
1177     , m_fpr(InvalidFPRReg)
1178 {
1179     if (m_jit->canReuse(op1.node()))
1180         m_fpr = m_jit->reuse(op1.fpr());
1181     else if (m_jit->canReuse(op2.node()))
1182         m_fpr = m_jit->reuse(op2.fpr());
1183     else if (m_jit->canReuse(op1.node(), op2.node()) && op1.fpr() == op2.fpr())
1184         m_fpr = m_jit->reuse(op1.fpr());
1185     else
1186         m_fpr = m_jit->fprAllocate();
1187 }
1188
1189 #if USE(JSVALUE32_64)
1190 FPRTemporary::FPRTemporary(SpeculativeJIT* jit, JSValueOperand& op1)
1191     : m_jit(jit)
1192     , m_fpr(InvalidFPRReg)
1193 {
1194     if (op1.isDouble() && m_jit->canReuse(op1.node()))
1195         m_fpr = m_jit->reuse(op1.fpr());
1196     else
1197         m_fpr = m_jit->fprAllocate();
1198 }
1199 #endif
1200
1201 void SpeculativeJIT::compilePeepHoleDoubleBranch(Node* node, Node* branchNode, JITCompiler::DoubleCondition condition)
1202 {
1203     BasicBlock* taken = branchNode->branchData()->taken.block;
1204     BasicBlock* notTaken = branchNode->branchData()->notTaken.block;
1205
1206     SpeculateDoubleOperand op1(this, node->child1());
1207     SpeculateDoubleOperand op2(this, node->child2());
1208
1209     branchDouble(condition, op1.fpr(), op2.fpr(), taken);
1210     jump(notTaken);
1211 }
1212
1213 void SpeculativeJIT::compilePeepHoleObjectEquality(Node* node, Node* branchNode)
1214 {
1215     BasicBlock* taken = branchNode->branchData()->taken.block;
1216     BasicBlock* notTaken = branchNode->branchData()->notTaken.block;
1217
1218     MacroAssembler::RelationalCondition condition = MacroAssembler::Equal;
1219
1220     if (taken == nextBlock()) {
1221         condition = MacroAssembler::NotEqual;
1222         BasicBlock* tmp = taken;
1223         taken = notTaken;
1224         notTaken = tmp;
1225     }
1226
1227     SpeculateCellOperand op1(this, node->child1());
1228     SpeculateCellOperand op2(this, node->child2());
1229
1230     GPRReg op1GPR = op1.gpr();
1231     GPRReg op2GPR = op2.gpr();
1232
1233     if (masqueradesAsUndefinedWatchpointIsStillValid()) {
1234         if (m_state.forNode(node->child1()).m_type & ~SpecObject) {
1235             speculationCheck(
1236                 BadType, JSValueSource::unboxedCell(op1GPR), node->child1(), m_jit.branchIfNotObject(op1GPR));
1237         }
1238         if (m_state.forNode(node->child2()).m_type & ~SpecObject) {
1239             speculationCheck(
1240                 BadType, JSValueSource::unboxedCell(op2GPR), node->child2(), m_jit.branchIfNotObject(op2GPR));
1241         }
1242     } else {
1243         if (m_state.forNode(node->child1()).m_type & ~SpecObject) {
1244             speculationCheck(
1245                 BadType, JSValueSource::unboxedCell(op1GPR), node->child1(),
1246                 m_jit.branchIfNotObject(op1GPR));
1247         }
1248         speculationCheck(BadType, JSValueSource::unboxedCell(op1GPR), node->child1(),
1249             m_jit.branchTest8(
1250                 MacroAssembler::NonZero,
1251                 MacroAssembler::Address(op1GPR, JSCell::typeInfoFlagsOffset()),
1252                 MacroAssembler::TrustedImm32(MasqueradesAsUndefined)));
1253
1254         if (m_state.forNode(node->child2()).m_type & ~SpecObject) {
1255             speculationCheck(
1256                 BadType, JSValueSource::unboxedCell(op2GPR), node->child2(),
1257                 m_jit.branchIfNotObject(op2GPR));
1258         }
1259         speculationCheck(BadType, JSValueSource::unboxedCell(op2GPR), node->child2(),
1260             m_jit.branchTest8(
1261                 MacroAssembler::NonZero,
1262                 MacroAssembler::Address(op2GPR, JSCell::typeInfoFlagsOffset()),
1263                 MacroAssembler::TrustedImm32(MasqueradesAsUndefined)));
1264     }
1265
1266     branchPtr(condition, op1GPR, op2GPR, taken);
1267     jump(notTaken);
1268 }
1269
1270 void SpeculativeJIT::compilePeepHoleBooleanBranch(Node* node, Node* branchNode, JITCompiler::RelationalCondition condition)
1271 {
1272     BasicBlock* taken = branchNode->branchData()->taken.block;
1273     BasicBlock* notTaken = branchNode->branchData()->notTaken.block;
1274
1275     // The branch instruction will branch to the taken block.
1276     // If taken is next, switch taken with notTaken & invert the branch condition so we can fall through.
1277     if (taken == nextBlock()) {
1278         condition = JITCompiler::invert(condition);
1279         BasicBlock* tmp = taken;
1280         taken = notTaken;
1281         notTaken = tmp;
1282     }
1283
1284     if (node->child1()->isBooleanConstant()) {
1285         bool imm = node->child1()->asBoolean();
1286         SpeculateBooleanOperand op2(this, node->child2());
1287         branch32(condition, JITCompiler::Imm32(static_cast<int32_t>(JSValue::encode(jsBoolean(imm)))), op2.gpr(), taken);
1288     } else if (node->child2()->isBooleanConstant()) {
1289         SpeculateBooleanOperand op1(this, node->child1());
1290         bool imm = node->child2()->asBoolean();
1291         branch32(condition, op1.gpr(), JITCompiler::Imm32(static_cast<int32_t>(JSValue::encode(jsBoolean(imm)))), taken);
1292     } else {
1293         SpeculateBooleanOperand op1(this, node->child1());
1294         SpeculateBooleanOperand op2(this, node->child2());
1295         branch32(condition, op1.gpr(), op2.gpr(), taken);
1296     }
1297
1298     jump(notTaken);
1299 }
1300
1301 void SpeculativeJIT::compilePeepHoleInt32Branch(Node* node, Node* branchNode, JITCompiler::RelationalCondition condition)
1302 {
1303     BasicBlock* taken = branchNode->branchData()->taken.block;
1304     BasicBlock* notTaken = branchNode->branchData()->notTaken.block;
1305
1306     // The branch instruction will branch to the taken block.
1307     // If taken is next, switch taken with notTaken & invert the branch condition so we can fall through.
1308     if (taken == nextBlock()) {
1309         condition = JITCompiler::invert(condition);
1310         BasicBlock* tmp = taken;
1311         taken = notTaken;
1312         notTaken = tmp;
1313     }
1314
1315     if (node->child1()->isInt32Constant()) {
1316         int32_t imm = node->child1()->asInt32();
1317         SpeculateInt32Operand op2(this, node->child2());
1318         branch32(condition, JITCompiler::Imm32(imm), op2.gpr(), taken);
1319     } else if (node->child2()->isInt32Constant()) {
1320         SpeculateInt32Operand op1(this, node->child1());
1321         int32_t imm = node->child2()->asInt32();
1322         branch32(condition, op1.gpr(), JITCompiler::Imm32(imm), taken);
1323     } else {
1324         SpeculateInt32Operand op1(this, node->child1());
1325         SpeculateInt32Operand op2(this, node->child2());
1326         branch32(condition, op1.gpr(), op2.gpr(), taken);
1327     }
1328
1329     jump(notTaken);
1330 }
1331
1332 // Returns true if the compare is fused with a subsequent branch.
1333 bool SpeculativeJIT::compilePeepHoleBranch(Node* node, MacroAssembler::RelationalCondition condition, MacroAssembler::DoubleCondition doubleCondition, S_JITOperation_EJJ operation)
1334 {
1335     // Fused compare & branch.
1336     unsigned branchIndexInBlock = detectPeepHoleBranch();
1337     if (branchIndexInBlock != UINT_MAX) {
1338         Node* branchNode = m_block->at(branchIndexInBlock);
1339
1340         // detectPeepHoleBranch currently only permits the branch to be the very next node,
1341         // so can be no intervening nodes to also reference the compare.
1342         ASSERT(node->adjustedRefCount() == 1);
1343
1344         if (node->isBinaryUseKind(Int32Use))
1345             compilePeepHoleInt32Branch(node, branchNode, condition);
1346 #if USE(JSVALUE64)
1347         else if (node->isBinaryUseKind(Int52RepUse))
1348             compilePeepHoleInt52Branch(node, branchNode, condition);
1349 #endif // USE(JSVALUE64)
1350         else if (node->isBinaryUseKind(DoubleRepUse))
1351             compilePeepHoleDoubleBranch(node, branchNode, doubleCondition);
1352         else if (node->op() == CompareEq) {
1353             if (node->isBinaryUseKind(StringUse) || node->isBinaryUseKind(StringIdentUse)) {
1354                 // Use non-peephole comparison, for now.
1355                 return false;
1356             }
1357             if (node->isBinaryUseKind(BooleanUse))
1358                 compilePeepHoleBooleanBranch(node, branchNode, condition);
1359             else if (node->isBinaryUseKind(ObjectUse))
1360                 compilePeepHoleObjectEquality(node, branchNode);
1361             else if (node->isBinaryUseKind(ObjectUse, ObjectOrOtherUse))
1362                 compilePeepHoleObjectToObjectOrOtherEquality(node->child1(), node->child2(), branchNode);
1363             else if (node->isBinaryUseKind(ObjectOrOtherUse, ObjectUse))
1364                 compilePeepHoleObjectToObjectOrOtherEquality(node->child2(), node->child1(), branchNode);
1365             else if (!needsTypeCheck(node->child1(), SpecOther))
1366                 nonSpeculativePeepholeBranchNullOrUndefined(node->child2(), branchNode);
1367             else if (!needsTypeCheck(node->child2(), SpecOther))
1368                 nonSpeculativePeepholeBranchNullOrUndefined(node->child1(), branchNode);
1369             else {
1370                 nonSpeculativePeepholeBranch(node, branchNode, condition, operation);
1371                 return true;
1372             }
1373         } else {
1374             nonSpeculativePeepholeBranch(node, branchNode, condition, operation);
1375             return true;
1376         }
1377
1378         use(node->child1());
1379         use(node->child2());
1380         m_indexInBlock = branchIndexInBlock;
1381         m_currentNode = branchNode;
1382         return true;
1383     }
1384     return false;
1385 }
1386
1387 void SpeculativeJIT::noticeOSRBirth(Node* node)
1388 {
1389     if (!node->hasVirtualRegister())
1390         return;
1391
1392     VirtualRegister virtualRegister = node->virtualRegister();
1393     GenerationInfo& info = generationInfoFromVirtualRegister(virtualRegister);
1394
1395     info.noticeOSRBirth(*m_stream, node, virtualRegister);
1396 }
1397
1398 void SpeculativeJIT::compileMovHint(Node* node)
1399 {
1400     ASSERT(node->containsMovHint() && node->op() != ZombieHint);
1401
1402     Node* child = node->child1().node();
1403     noticeOSRBirth(child);
1404
1405     m_stream->appendAndLog(VariableEvent::movHint(MinifiedID(child), node->unlinkedLocal()));
1406 }
1407
1408 void SpeculativeJIT::bail(AbortReason reason)
1409 {
1410     if (verboseCompilationEnabled())
1411         dataLog("Bailing compilation.\n");
1412     m_compileOkay = true;
1413     m_jit.abortWithReason(reason, m_lastGeneratedNode);
1414     clearGenerationInfo();
1415 }
1416
1417 void SpeculativeJIT::compileCurrentBlock()
1418 {
1419     ASSERT(m_compileOkay);
1420
1421     if (!m_block)
1422         return;
1423
1424     ASSERT(m_block->isReachable);
1425
1426     m_jit.blockHeads()[m_block->index] = m_jit.label();
1427
1428     if (!m_block->intersectionOfCFAHasVisited) {
1429         // Don't generate code for basic blocks that are unreachable according to CFA.
1430         // But to be sure that nobody has generated a jump to this block, drop in a
1431         // breakpoint here.
1432         m_jit.abortWithReason(DFGUnreachableBasicBlock);
1433         return;
1434     }
1435
1436     m_stream->appendAndLog(VariableEvent::reset());
1437
1438     m_jit.jitAssertHasValidCallFrame();
1439     m_jit.jitAssertTagsInPlace();
1440     m_jit.jitAssertArgumentCountSane();
1441
1442     m_state.reset();
1443     m_state.beginBasicBlock(m_block);
1444
1445     for (size_t i = m_block->variablesAtHead.size(); i--;) {
1446         int operand = m_block->variablesAtHead.operandForIndex(i);
1447         Node* node = m_block->variablesAtHead[i];
1448         if (!node)
1449             continue; // No need to record dead SetLocal's.
1450
1451         VariableAccessData* variable = node->variableAccessData();
1452         DataFormat format;
1453         if (!node->refCount())
1454             continue; // No need to record dead SetLocal's.
1455         format = dataFormatFor(variable->flushFormat());
1456         m_stream->appendAndLog(
1457             VariableEvent::setLocal(
1458                 VirtualRegister(operand),
1459                 variable->machineLocal(),
1460                 format));
1461     }
1462
1463     m_origin = NodeOrigin();
1464
1465     for (m_indexInBlock = 0; m_indexInBlock < m_block->size(); ++m_indexInBlock) {
1466         m_currentNode = m_block->at(m_indexInBlock);
1467
1468         // We may have hit a contradiction that the CFA was aware of but that the JIT
1469         // didn't cause directly.
1470         if (!m_state.isValid()) {
1471             bail(DFGBailedAtTopOfBlock);
1472             return;
1473         }
1474
1475         m_interpreter.startExecuting();
1476         m_jit.setForNode(m_currentNode);
1477         m_origin = m_currentNode->origin;
1478         if (validationEnabled())
1479             m_origin.exitOK &= mayExit(m_jit.graph(), m_currentNode) == Exits;
1480         m_lastGeneratedNode = m_currentNode->op();
1481
1482         ASSERT(m_currentNode->shouldGenerate());
1483
1484         if (verboseCompilationEnabled()) {
1485             dataLogF(
1486                 "SpeculativeJIT generating Node @%d (bc#%u) at JIT offset 0x%x",
1487                 (int)m_currentNode->index(),
1488                 m_currentNode->origin.semantic.bytecodeIndex, m_jit.debugOffset());
1489             dataLog("\n");
1490         }
1491
1492         m_jit.jitAssertNoException();
1493
1494         compile(m_currentNode);
1495
1496         if (belongsInMinifiedGraph(m_currentNode->op()))
1497             m_minifiedGraph->append(MinifiedNode::fromNode(m_currentNode));
1498
1499 #if ENABLE(DFG_REGISTER_ALLOCATION_VALIDATION)
1500         m_jit.clearRegisterAllocationOffsets();
1501 #endif
1502
1503         if (!m_compileOkay) {
1504             bail(DFGBailedAtEndOfNode);
1505             return;
1506         }
1507
1508         // Make sure that the abstract state is rematerialized for the next node.
1509         m_interpreter.executeEffects(m_indexInBlock);
1510     }
1511
1512     // Perform the most basic verification that children have been used correctly.
1513     if (!ASSERT_DISABLED) {
1514         for (unsigned index = 0; index < m_generationInfo.size(); ++index) {
1515             GenerationInfo& info = m_generationInfo[index];
1516             RELEASE_ASSERT(!info.alive());
1517         }
1518     }
1519 }
1520
1521 // If we are making type predictions about our arguments then
1522 // we need to check that they are correct on function entry.
1523 void SpeculativeJIT::checkArgumentTypes()
1524 {
1525     ASSERT(!m_currentNode);
1526     m_origin = NodeOrigin(CodeOrigin(0), CodeOrigin(0), true);
1527
1528     for (int i = 0; i < m_jit.codeBlock()->numParameters(); ++i) {
1529         Node* node = m_jit.graph().m_arguments[i];
1530         if (!node) {
1531             // The argument is dead. We don't do any checks for such arguments.
1532             continue;
1533         }
1534
1535         ASSERT(node->op() == SetArgument);
1536         ASSERT(node->shouldGenerate());
1537
1538         VariableAccessData* variableAccessData = node->variableAccessData();
1539         FlushFormat format = variableAccessData->flushFormat();
1540
1541         if (format == FlushedJSValue)
1542             continue;
1543
1544         VirtualRegister virtualRegister = variableAccessData->local();
1545
1546         JSValueSource valueSource = JSValueSource(JITCompiler::addressFor(virtualRegister));
1547
1548 #if USE(JSVALUE64)
1549         switch (format) {
1550         case FlushedInt32: {
1551             speculationCheck(BadType, valueSource, node, m_jit.branch64(MacroAssembler::Below, JITCompiler::addressFor(virtualRegister), GPRInfo::tagTypeNumberRegister));
1552             break;
1553         }
1554         case FlushedBoolean: {
1555             GPRTemporary temp(this);
1556             m_jit.load64(JITCompiler::addressFor(virtualRegister), temp.gpr());
1557             m_jit.xor64(TrustedImm32(static_cast<int32_t>(ValueFalse)), temp.gpr());
1558             speculationCheck(BadType, valueSource, node, m_jit.branchTest64(MacroAssembler::NonZero, temp.gpr(), TrustedImm32(static_cast<int32_t>(~1))));
1559             break;
1560         }
1561         case FlushedCell: {
1562             speculationCheck(BadType, valueSource, node, m_jit.branchTest64(MacroAssembler::NonZero, JITCompiler::addressFor(virtualRegister), GPRInfo::tagMaskRegister));
1563             break;
1564         }
1565         default:
1566             RELEASE_ASSERT_NOT_REACHED();
1567             break;
1568         }
1569 #else
1570         switch (format) {
1571         case FlushedInt32: {
1572             speculationCheck(BadType, valueSource, node, m_jit.branch32(MacroAssembler::NotEqual, JITCompiler::tagFor(virtualRegister), TrustedImm32(JSValue::Int32Tag)));
1573             break;
1574         }
1575         case FlushedBoolean: {
1576             speculationCheck(BadType, valueSource, node, m_jit.branch32(MacroAssembler::NotEqual, JITCompiler::tagFor(virtualRegister), TrustedImm32(JSValue::BooleanTag)));
1577             break;
1578         }
1579         case FlushedCell: {
1580             speculationCheck(BadType, valueSource, node, m_jit.branch32(MacroAssembler::NotEqual, JITCompiler::tagFor(virtualRegister), TrustedImm32(JSValue::CellTag)));
1581             break;
1582         }
1583         default:
1584             RELEASE_ASSERT_NOT_REACHED();
1585             break;
1586         }
1587 #endif
1588     }
1589
1590     m_origin = NodeOrigin();
1591 }
1592
1593 bool SpeculativeJIT::compile()
1594 {
1595     checkArgumentTypes();
1596
1597     ASSERT(!m_currentNode);
1598     for (BlockIndex blockIndex = 0; blockIndex < m_jit.graph().numBlocks(); ++blockIndex) {
1599         m_jit.setForBlockIndex(blockIndex);
1600         m_block = m_jit.graph().block(blockIndex);
1601         compileCurrentBlock();
1602     }
1603     linkBranches();
1604     return true;
1605 }
1606
1607 void SpeculativeJIT::createOSREntries()
1608 {
1609     for (BlockIndex blockIndex = 0; blockIndex < m_jit.graph().numBlocks(); ++blockIndex) {
1610         BasicBlock* block = m_jit.graph().block(blockIndex);
1611         if (!block)
1612             continue;
1613         if (!block->isOSRTarget)
1614             continue;
1615
1616         // Currently we don't have OSR entry trampolines. We could add them
1617         // here if need be.
1618         m_osrEntryHeads.append(m_jit.blockHeads()[blockIndex]);
1619     }
1620 }
1621
1622 void SpeculativeJIT::linkOSREntries(LinkBuffer& linkBuffer)
1623 {
1624     unsigned osrEntryIndex = 0;
1625     for (BlockIndex blockIndex = 0; blockIndex < m_jit.graph().numBlocks(); ++blockIndex) {
1626         BasicBlock* block = m_jit.graph().block(blockIndex);
1627         if (!block)
1628             continue;
1629         if (!block->isOSRTarget)
1630             continue;
1631         m_jit.noticeOSREntry(*block, m_osrEntryHeads[osrEntryIndex++], linkBuffer);
1632     }
1633     ASSERT(osrEntryIndex == m_osrEntryHeads.size());
1634
1635     if (verboseCompilationEnabled()) {
1636         DumpContext dumpContext;
1637         dataLog("OSR Entries:\n");
1638         for (OSREntryData& entryData : m_jit.jitCode()->osrEntry)
1639             dataLog("    ", inContext(entryData, &dumpContext), "\n");
1640         if (!dumpContext.isEmpty())
1641             dumpContext.dump(WTF::dataFile());
1642     }
1643 }
1644
1645 void SpeculativeJIT::compileDoublePutByVal(Node* node, SpeculateCellOperand& base, SpeculateStrictInt32Operand& property)
1646 {
1647     Edge child3 = m_jit.graph().varArgChild(node, 2);
1648     Edge child4 = m_jit.graph().varArgChild(node, 3);
1649
1650     ArrayMode arrayMode = node->arrayMode();
1651
1652     GPRReg baseReg = base.gpr();
1653     GPRReg propertyReg = property.gpr();
1654
1655     SpeculateDoubleOperand value(this, child3);
1656
1657     FPRReg valueReg = value.fpr();
1658
1659     DFG_TYPE_CHECK(
1660         JSValueRegs(), child3, SpecFullRealNumber,
1661         m_jit.branchDouble(
1662             MacroAssembler::DoubleNotEqualOrUnordered, valueReg, valueReg));
1663
1664     if (!m_compileOkay)
1665         return;
1666
1667     StorageOperand storage(this, child4);
1668     GPRReg storageReg = storage.gpr();
1669
1670     if (node->op() == PutByValAlias) {
1671         // Store the value to the array.
1672         GPRReg propertyReg = property.gpr();
1673         FPRReg valueReg = value.fpr();
1674         m_jit.storeDouble(valueReg, MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesEight));
1675
1676         noResult(m_currentNode);
1677         return;
1678     }
1679
1680     GPRTemporary temporary;
1681     GPRReg temporaryReg = temporaryRegisterForPutByVal(temporary, node);
1682
1683     MacroAssembler::Jump slowCase;
1684
1685     if (arrayMode.isInBounds()) {
1686         speculationCheck(
1687             OutOfBounds, JSValueRegs(), 0,
1688             m_jit.branch32(MacroAssembler::AboveOrEqual, propertyReg, MacroAssembler::Address(storageReg, Butterfly::offsetOfPublicLength())));
1689     } else {
1690         MacroAssembler::Jump inBounds = m_jit.branch32(MacroAssembler::Below, propertyReg, MacroAssembler::Address(storageReg, Butterfly::offsetOfPublicLength()));
1691
1692         slowCase = m_jit.branch32(MacroAssembler::AboveOrEqual, propertyReg, MacroAssembler::Address(storageReg, Butterfly::offsetOfVectorLength()));
1693
1694         if (!arrayMode.isOutOfBounds())
1695             speculationCheck(OutOfBounds, JSValueRegs(), 0, slowCase);
1696
1697         m_jit.add32(TrustedImm32(1), propertyReg, temporaryReg);
1698         m_jit.store32(temporaryReg, MacroAssembler::Address(storageReg, Butterfly::offsetOfPublicLength()));
1699
1700         inBounds.link(&m_jit);
1701     }
1702
1703     m_jit.storeDouble(valueReg, MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesEight));
1704
1705     base.use();
1706     property.use();
1707     value.use();
1708     storage.use();
1709
1710     if (arrayMode.isOutOfBounds()) {
1711         addSlowPathGenerator(
1712             slowPathCall(
1713                 slowCase, this,
1714                 m_jit.codeBlock()->isStrictMode() ? operationPutDoubleByValBeyondArrayBoundsStrict : operationPutDoubleByValBeyondArrayBoundsNonStrict,
1715                 NoResult, baseReg, propertyReg, valueReg));
1716     }
1717
1718     noResult(m_currentNode, UseChildrenCalledExplicitly);
1719 }
1720
1721 void SpeculativeJIT::compileGetCharCodeAt(Node* node)
1722 {
1723     SpeculateCellOperand string(this, node->child1());
1724     SpeculateStrictInt32Operand index(this, node->child2());
1725     StorageOperand storage(this, node->child3());
1726
1727     GPRReg stringReg = string.gpr();
1728     GPRReg indexReg = index.gpr();
1729     GPRReg storageReg = storage.gpr();
1730
1731     ASSERT(speculationChecked(m_state.forNode(node->child1()).m_type, SpecString));
1732
1733     // unsigned comparison so we can filter out negative indices and indices that are too large
1734     speculationCheck(Uncountable, JSValueRegs(), 0, m_jit.branch32(MacroAssembler::AboveOrEqual, indexReg, MacroAssembler::Address(stringReg, JSString::offsetOfLength())));
1735
1736     GPRTemporary scratch(this);
1737     GPRReg scratchReg = scratch.gpr();
1738
1739     m_jit.loadPtr(MacroAssembler::Address(stringReg, JSString::offsetOfValue()), scratchReg);
1740
1741     // Load the character into scratchReg
1742     JITCompiler::Jump is16Bit = m_jit.branchTest32(MacroAssembler::Zero, MacroAssembler::Address(scratchReg, StringImpl::flagsOffset()), TrustedImm32(StringImpl::flagIs8Bit()));
1743
1744     m_jit.load8(MacroAssembler::BaseIndex(storageReg, indexReg, MacroAssembler::TimesOne, 0), scratchReg);
1745     JITCompiler::Jump cont8Bit = m_jit.jump();
1746
1747     is16Bit.link(&m_jit);
1748
1749     m_jit.load16(MacroAssembler::BaseIndex(storageReg, indexReg, MacroAssembler::TimesTwo, 0), scratchReg);
1750
1751     cont8Bit.link(&m_jit);
1752
1753     int32Result(scratchReg, m_currentNode);
1754 }
1755
1756 void SpeculativeJIT::compileGetByValOnString(Node* node)
1757 {
1758     SpeculateCellOperand base(this, node->child1());
1759     SpeculateStrictInt32Operand property(this, node->child2());
1760     StorageOperand storage(this, node->child3());
1761     GPRReg baseReg = base.gpr();
1762     GPRReg propertyReg = property.gpr();
1763     GPRReg storageReg = storage.gpr();
1764
1765     GPRTemporary scratch(this);
1766     GPRReg scratchReg = scratch.gpr();
1767 #if USE(JSVALUE32_64)
1768     GPRTemporary resultTag;
1769     GPRReg resultTagReg = InvalidGPRReg;
1770     if (node->arrayMode().isOutOfBounds()) {
1771         GPRTemporary realResultTag(this);
1772         resultTag.adopt(realResultTag);
1773         resultTagReg = resultTag.gpr();
1774     }
1775 #endif
1776
1777     ASSERT(ArrayMode(Array::String).alreadyChecked(m_jit.graph(), node, m_state.forNode(node->child1())));
1778
1779     // unsigned comparison so we can filter out negative indices and indices that are too large
1780     JITCompiler::Jump outOfBounds = m_jit.branch32(
1781         MacroAssembler::AboveOrEqual, propertyReg,
1782         MacroAssembler::Address(baseReg, JSString::offsetOfLength()));
1783     if (node->arrayMode().isInBounds())
1784         speculationCheck(OutOfBounds, JSValueRegs(), 0, outOfBounds);
1785
1786     m_jit.loadPtr(MacroAssembler::Address(baseReg, JSString::offsetOfValue()), scratchReg);
1787
1788     // Load the character into scratchReg
1789     JITCompiler::Jump is16Bit = m_jit.branchTest32(MacroAssembler::Zero, MacroAssembler::Address(scratchReg, StringImpl::flagsOffset()), TrustedImm32(StringImpl::flagIs8Bit()));
1790
1791     m_jit.load8(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesOne, 0), scratchReg);
1792     JITCompiler::Jump cont8Bit = m_jit.jump();
1793
1794     is16Bit.link(&m_jit);
1795
1796     m_jit.load16(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesTwo, 0), scratchReg);
1797
1798     JITCompiler::Jump bigCharacter =
1799         m_jit.branch32(MacroAssembler::AboveOrEqual, scratchReg, TrustedImm32(0x100));
1800
1801     // 8 bit string values don't need the isASCII check.
1802     cont8Bit.link(&m_jit);
1803
1804     m_jit.lshift32(MacroAssembler::TrustedImm32(sizeof(void*) == 4 ? 2 : 3), scratchReg);
1805     m_jit.addPtr(MacroAssembler::TrustedImmPtr(m_jit.vm()->smallStrings.singleCharacterStrings()), scratchReg);
1806     m_jit.loadPtr(scratchReg, scratchReg);
1807
1808     addSlowPathGenerator(
1809         slowPathCall(
1810             bigCharacter, this, operationSingleCharacterString, scratchReg, scratchReg));
1811
1812     if (node->arrayMode().isOutOfBounds()) {
1813 #if USE(JSVALUE32_64)
1814         m_jit.move(TrustedImm32(JSValue::CellTag), resultTagReg);
1815 #endif
1816
1817         JSGlobalObject* globalObject = m_jit.globalObjectFor(node->origin.semantic);
1818         if (globalObject->stringPrototypeChainIsSane()) {
1819             // FIXME: This could be captured using a Speculation mode that means "out-of-bounds
1820             // loads return a trivial value". Something like SaneChainOutOfBounds. This should
1821             // speculate that we don't take negative out-of-bounds, or better yet, it should rely
1822             // on a stringPrototypeChainIsSane() guaranteeing that the prototypes have no negative
1823             // indexed properties either.
1824             // https://bugs.webkit.org/show_bug.cgi?id=144668
1825             m_jit.graph().watchpoints().addLazily(globalObject->stringPrototype()->structure()->transitionWatchpointSet());
1826             m_jit.graph().watchpoints().addLazily(globalObject->objectPrototype()->structure()->transitionWatchpointSet());
1827
1828 #if USE(JSVALUE64)
1829             addSlowPathGenerator(std::make_unique<SaneStringGetByValSlowPathGenerator>(
1830                 outOfBounds, this, JSValueRegs(scratchReg), baseReg, propertyReg));
1831 #else
1832             addSlowPathGenerator(std::make_unique<SaneStringGetByValSlowPathGenerator>(
1833                 outOfBounds, this, JSValueRegs(resultTagReg, scratchReg),
1834                 baseReg, propertyReg));
1835 #endif
1836         } else {
1837 #if USE(JSVALUE64)
1838             addSlowPathGenerator(
1839                 slowPathCall(
1840                     outOfBounds, this, operationGetByValStringInt,
1841                     scratchReg, baseReg, propertyReg));
1842 #else
1843             addSlowPathGenerator(
1844                 slowPathCall(
1845                     outOfBounds, this, operationGetByValStringInt,
1846                     resultTagReg, scratchReg, baseReg, propertyReg));
1847 #endif
1848         }
1849
1850 #if USE(JSVALUE64)
1851         jsValueResult(scratchReg, m_currentNode);
1852 #else
1853         jsValueResult(resultTagReg, scratchReg, m_currentNode);
1854 #endif
1855     } else
1856         cellResult(scratchReg, m_currentNode);
1857 }
1858
1859 void SpeculativeJIT::compileFromCharCode(Node* node)
1860 {
1861     SpeculateStrictInt32Operand property(this, node->child1());
1862     GPRReg propertyReg = property.gpr();
1863     GPRTemporary smallStrings(this);
1864     GPRTemporary scratch(this);
1865     GPRReg scratchReg = scratch.gpr();
1866     GPRReg smallStringsReg = smallStrings.gpr();
1867
1868     JITCompiler::JumpList slowCases;
1869     slowCases.append(m_jit.branch32(MacroAssembler::AboveOrEqual, propertyReg, TrustedImm32(0xff)));
1870     m_jit.move(MacroAssembler::TrustedImmPtr(m_jit.vm()->smallStrings.singleCharacterStrings()), smallStringsReg);
1871     m_jit.loadPtr(MacroAssembler::BaseIndex(smallStringsReg, propertyReg, MacroAssembler::ScalePtr, 0), scratchReg);
1872
1873     slowCases.append(m_jit.branchTest32(MacroAssembler::Zero, scratchReg));
1874     addSlowPathGenerator(slowPathCall(slowCases, this, operationStringFromCharCode, scratchReg, propertyReg));
1875     cellResult(scratchReg, m_currentNode);
1876 }
1877
1878 GeneratedOperandType SpeculativeJIT::checkGeneratedTypeForToInt32(Node* node)
1879 {
1880     VirtualRegister virtualRegister = node->virtualRegister();
1881     GenerationInfo& info = generationInfoFromVirtualRegister(virtualRegister);
1882
1883     switch (info.registerFormat()) {
1884     case DataFormatStorage:
1885         RELEASE_ASSERT_NOT_REACHED();
1886
1887     case DataFormatBoolean:
1888     case DataFormatCell:
1889         terminateSpeculativeExecution(Uncountable, JSValueRegs(), 0);
1890         return GeneratedOperandTypeUnknown;
1891
1892     case DataFormatNone:
1893     case DataFormatJSCell:
1894     case DataFormatJS:
1895     case DataFormatJSBoolean:
1896     case DataFormatJSDouble:
1897         return GeneratedOperandJSValue;
1898
1899     case DataFormatJSInt32:
1900     case DataFormatInt32:
1901         return GeneratedOperandInteger;
1902
1903     default:
1904         RELEASE_ASSERT_NOT_REACHED();
1905         return GeneratedOperandTypeUnknown;
1906     }
1907 }
1908
1909 void SpeculativeJIT::compileValueToInt32(Node* node)
1910 {
1911     switch (node->child1().useKind()) {
1912 #if USE(JSVALUE64)
1913     case Int52RepUse: {
1914         SpeculateStrictInt52Operand op1(this, node->child1());
1915         GPRTemporary result(this, Reuse, op1);
1916         GPRReg op1GPR = op1.gpr();
1917         GPRReg resultGPR = result.gpr();
1918         m_jit.zeroExtend32ToPtr(op1GPR, resultGPR);
1919         int32Result(resultGPR, node, DataFormatInt32);
1920         return;
1921     }
1922 #endif // USE(JSVALUE64)
1923
1924     case DoubleRepUse: {
1925         GPRTemporary result(this);
1926         SpeculateDoubleOperand op1(this, node->child1());
1927         FPRReg fpr = op1.fpr();
1928         GPRReg gpr = result.gpr();
1929         JITCompiler::Jump notTruncatedToInteger = m_jit.branchTruncateDoubleToInt32(fpr, gpr, JITCompiler::BranchIfTruncateFailed);
1930
1931         addSlowPathGenerator(slowPathCall(notTruncatedToInteger, this, toInt32, gpr, fpr, NeedToSpill, ExceptionCheckRequirement::CheckNotNeeded));
1932
1933         int32Result(gpr, node);
1934         return;
1935     }
1936
1937     case NumberUse:
1938     case NotCellUse: {
1939         switch (checkGeneratedTypeForToInt32(node->child1().node())) {
1940         case GeneratedOperandInteger: {
1941             SpeculateInt32Operand op1(this, node->child1(), ManualOperandSpeculation);
1942             GPRTemporary result(this, Reuse, op1);
1943             m_jit.move(op1.gpr(), result.gpr());
1944             int32Result(result.gpr(), node, op1.format());
1945             return;
1946         }
1947         case GeneratedOperandJSValue: {
1948             GPRTemporary result(this);
1949 #if USE(JSVALUE64)
1950             JSValueOperand op1(this, node->child1(), ManualOperandSpeculation);
1951
1952             GPRReg gpr = op1.gpr();
1953             GPRReg resultGpr = result.gpr();
1954             FPRTemporary tempFpr(this);
1955             FPRReg fpr = tempFpr.fpr();
1956
1957             JITCompiler::Jump isInteger = m_jit.branch64(MacroAssembler::AboveOrEqual, gpr, GPRInfo::tagTypeNumberRegister);
1958             JITCompiler::JumpList converted;
1959
1960             if (node->child1().useKind() == NumberUse) {
1961                 DFG_TYPE_CHECK(
1962                     JSValueRegs(gpr), node->child1(), SpecBytecodeNumber,
1963                     m_jit.branchTest64(
1964                         MacroAssembler::Zero, gpr, GPRInfo::tagTypeNumberRegister));
1965             } else {
1966                 JITCompiler::Jump isNumber = m_jit.branchTest64(MacroAssembler::NonZero, gpr, GPRInfo::tagTypeNumberRegister);
1967
1968                 DFG_TYPE_CHECK(
1969                     JSValueRegs(gpr), node->child1(), ~SpecCell, m_jit.branchIfCell(JSValueRegs(gpr)));
1970
1971                 // It's not a cell: so true turns into 1 and all else turns into 0.
1972                 m_jit.compare64(JITCompiler::Equal, gpr, TrustedImm32(ValueTrue), resultGpr);
1973                 converted.append(m_jit.jump());
1974
1975                 isNumber.link(&m_jit);
1976             }
1977
1978             // First, if we get here we have a double encoded as a JSValue
1979             m_jit.move(gpr, resultGpr);
1980             unboxDouble(resultGpr, fpr);
1981
1982             silentSpillAllRegisters(resultGpr);
1983             callOperation(toInt32, resultGpr, fpr);
1984             silentFillAllRegisters(resultGpr);
1985
1986             converted.append(m_jit.jump());
1987
1988             isInteger.link(&m_jit);
1989             m_jit.zeroExtend32ToPtr(gpr, resultGpr);
1990
1991             converted.link(&m_jit);
1992 #else
1993             Node* childNode = node->child1().node();
1994             VirtualRegister virtualRegister = childNode->virtualRegister();
1995             GenerationInfo& info = generationInfoFromVirtualRegister(virtualRegister);
1996
1997             JSValueOperand op1(this, node->child1(), ManualOperandSpeculation);
1998
1999             GPRReg payloadGPR = op1.payloadGPR();
2000             GPRReg resultGpr = result.gpr();
2001
2002             JITCompiler::JumpList converted;
2003
2004             if (info.registerFormat() == DataFormatJSInt32)
2005                 m_jit.move(payloadGPR, resultGpr);
2006             else {
2007                 GPRReg tagGPR = op1.tagGPR();
2008                 FPRTemporary tempFpr(this);
2009                 FPRReg fpr = tempFpr.fpr();
2010                 FPRTemporary scratch(this);
2011
2012                 JITCompiler::Jump isInteger = m_jit.branch32(MacroAssembler::Equal, tagGPR, TrustedImm32(JSValue::Int32Tag));
2013
2014                 if (node->child1().useKind() == NumberUse) {
2015                     DFG_TYPE_CHECK(
2016                         op1.jsValueRegs(), node->child1(), SpecBytecodeNumber,
2017                         m_jit.branch32(
2018                             MacroAssembler::AboveOrEqual, tagGPR,
2019                             TrustedImm32(JSValue::LowestTag)));
2020                 } else {
2021                     JITCompiler::Jump isNumber = m_jit.branch32(MacroAssembler::Below, tagGPR, TrustedImm32(JSValue::LowestTag));
2022
2023                     DFG_TYPE_CHECK(
2024                         op1.jsValueRegs(), node->child1(), ~SpecCell,
2025                         m_jit.branchIfCell(op1.jsValueRegs()));
2026
2027                     // It's not a cell: so true turns into 1 and all else turns into 0.
2028                     JITCompiler::Jump isBoolean = m_jit.branch32(JITCompiler::Equal, tagGPR, TrustedImm32(JSValue::BooleanTag));
2029                     m_jit.move(TrustedImm32(0), resultGpr);
2030                     converted.append(m_jit.jump());
2031
2032                     isBoolean.link(&m_jit);
2033                     m_jit.move(payloadGPR, resultGpr);
2034                     converted.append(m_jit.jump());
2035
2036                     isNumber.link(&m_jit);
2037                 }
2038
2039                 unboxDouble(tagGPR, payloadGPR, fpr, scratch.fpr());
2040
2041                 silentSpillAllRegisters(resultGpr);
2042                 callOperation(toInt32, resultGpr, fpr);
2043                 silentFillAllRegisters(resultGpr);
2044
2045                 converted.append(m_jit.jump());
2046
2047                 isInteger.link(&m_jit);
2048                 m_jit.move(payloadGPR, resultGpr);
2049
2050                 converted.link(&m_jit);
2051             }
2052 #endif
2053             int32Result(resultGpr, node);
2054             return;
2055         }
2056         case GeneratedOperandTypeUnknown:
2057             RELEASE_ASSERT(!m_compileOkay);
2058             return;
2059         }
2060         RELEASE_ASSERT_NOT_REACHED();
2061         return;
2062     }
2063
2064     default:
2065         ASSERT(!m_compileOkay);
2066         return;
2067     }
2068 }
2069
2070 void SpeculativeJIT::compileUInt32ToNumber(Node* node)
2071 {
2072     if (doesOverflow(node->arithMode())) {
2073         // We know that this sometimes produces doubles. So produce a double every
2074         // time. This at least allows subsequent code to not have weird conditionals.
2075
2076         SpeculateInt32Operand op1(this, node->child1());
2077         FPRTemporary result(this);
2078
2079         GPRReg inputGPR = op1.gpr();
2080         FPRReg outputFPR = result.fpr();
2081
2082         m_jit.convertInt32ToDouble(inputGPR, outputFPR);
2083
2084         JITCompiler::Jump positive = m_jit.branch32(MacroAssembler::GreaterThanOrEqual, inputGPR, TrustedImm32(0));
2085         m_jit.addDouble(JITCompiler::AbsoluteAddress(&AssemblyHelpers::twoToThe32), outputFPR);
2086         positive.link(&m_jit);
2087
2088         doubleResult(outputFPR, node);
2089         return;
2090     }
2091
2092     RELEASE_ASSERT(node->arithMode() == Arith::CheckOverflow);
2093
2094     SpeculateInt32Operand op1(this, node->child1());
2095     GPRTemporary result(this);
2096
2097     m_jit.move(op1.gpr(), result.gpr());
2098
2099     speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branch32(MacroAssembler::LessThan, result.gpr(), TrustedImm32(0)));
2100
2101     int32Result(result.gpr(), node, op1.format());
2102 }
2103
2104 void SpeculativeJIT::compileDoubleAsInt32(Node* node)
2105 {
2106     SpeculateDoubleOperand op1(this, node->child1());
2107     FPRTemporary scratch(this);
2108     GPRTemporary result(this);
2109
2110     FPRReg valueFPR = op1.fpr();
2111     FPRReg scratchFPR = scratch.fpr();
2112     GPRReg resultGPR = result.gpr();
2113
2114     JITCompiler::JumpList failureCases;
2115     RELEASE_ASSERT(shouldCheckOverflow(node->arithMode()));
2116     m_jit.branchConvertDoubleToInt32(
2117         valueFPR, resultGPR, failureCases, scratchFPR,
2118         shouldCheckNegativeZero(node->arithMode()));
2119     speculationCheck(Overflow, JSValueRegs(), 0, failureCases);
2120
2121     int32Result(resultGPR, node);
2122 }
2123
2124 void SpeculativeJIT::compileDoubleRep(Node* node)
2125 {
2126     switch (node->child1().useKind()) {
2127     case RealNumberUse: {
2128         JSValueOperand op1(this, node->child1(), ManualOperandSpeculation);
2129         FPRTemporary result(this);
2130
2131         JSValueRegs op1Regs = op1.jsValueRegs();
2132         FPRReg resultFPR = result.fpr();
2133
2134 #if USE(JSVALUE64)
2135         GPRTemporary temp(this);
2136         GPRReg tempGPR = temp.gpr();
2137         m_jit.move(op1Regs.gpr(), tempGPR);
2138         m_jit.unboxDoubleWithoutAssertions(tempGPR, resultFPR);
2139 #else
2140         FPRTemporary temp(this);
2141         FPRReg tempFPR = temp.fpr();
2142         unboxDouble(op1Regs.tagGPR(), op1Regs.payloadGPR(), resultFPR, tempFPR);
2143 #endif
2144
2145         JITCompiler::Jump done = m_jit.branchDouble(
2146             JITCompiler::DoubleEqual, resultFPR, resultFPR);
2147
2148         DFG_TYPE_CHECK(
2149             op1Regs, node->child1(), SpecBytecodeRealNumber, m_jit.branchIfNotInt32(op1Regs));
2150         m_jit.convertInt32ToDouble(op1Regs.payloadGPR(), resultFPR);
2151
2152         done.link(&m_jit);
2153
2154         doubleResult(resultFPR, node);
2155         return;
2156     }
2157
2158     case NotCellUse:
2159     case NumberUse: {
2160         ASSERT(!node->child1()->isNumberConstant()); // This should have been constant folded.
2161
2162         SpeculatedType possibleTypes = m_state.forNode(node->child1()).m_type;
2163         if (isInt32Speculation(possibleTypes)) {
2164             SpeculateInt32Operand op1(this, node->child1(), ManualOperandSpeculation);
2165             FPRTemporary result(this);
2166             m_jit.convertInt32ToDouble(op1.gpr(), result.fpr());
2167             doubleResult(result.fpr(), node);
2168             return;
2169         }
2170
2171         JSValueOperand op1(this, node->child1(), ManualOperandSpeculation);
2172         FPRTemporary result(this);
2173
2174 #if USE(JSVALUE64)
2175         GPRTemporary temp(this);
2176
2177         GPRReg op1GPR = op1.gpr();
2178         GPRReg tempGPR = temp.gpr();
2179         FPRReg resultFPR = result.fpr();
2180         JITCompiler::JumpList done;
2181
2182         JITCompiler::Jump isInteger = m_jit.branch64(
2183             MacroAssembler::AboveOrEqual, op1GPR, GPRInfo::tagTypeNumberRegister);
2184
2185         if (node->child1().useKind() == NotCellUse) {
2186             JITCompiler::Jump isNumber = m_jit.branchTest64(MacroAssembler::NonZero, op1GPR, GPRInfo::tagTypeNumberRegister);
2187             JITCompiler::Jump isUndefined = m_jit.branch64(JITCompiler::Equal, op1GPR, TrustedImm64(ValueUndefined));
2188
2189             static const double zero = 0;
2190             m_jit.loadDouble(MacroAssembler::TrustedImmPtr(&zero), resultFPR);
2191
2192             JITCompiler::Jump isNull = m_jit.branch64(JITCompiler::Equal, op1GPR, TrustedImm64(ValueNull));
2193             done.append(isNull);
2194
2195             DFG_TYPE_CHECK(JSValueRegs(op1GPR), node->child1(), ~SpecCell,
2196                 m_jit.branchTest64(JITCompiler::NonZero, op1GPR, TrustedImm32(static_cast<int32_t>(~1))));
2197
2198             JITCompiler::Jump isFalse = m_jit.branch64(JITCompiler::Equal, op1GPR, TrustedImm64(ValueFalse));
2199             static const double one = 1;
2200             m_jit.loadDouble(MacroAssembler::TrustedImmPtr(&one), resultFPR);
2201             done.append(isFalse);
2202
2203             isUndefined.link(&m_jit);
2204             static const double NaN = PNaN;
2205             m_jit.loadDouble(MacroAssembler::TrustedImmPtr(&NaN), resultFPR);
2206             done.append(m_jit.jump());
2207
2208             isNumber.link(&m_jit);
2209         } else if (needsTypeCheck(node->child1(), SpecBytecodeNumber)) {
2210             typeCheck(
2211                 JSValueRegs(op1GPR), node->child1(), SpecBytecodeNumber,
2212                 m_jit.branchTest64(MacroAssembler::Zero, op1GPR, GPRInfo::tagTypeNumberRegister));
2213         }
2214
2215         m_jit.move(op1GPR, tempGPR);
2216         unboxDouble(tempGPR, resultFPR);
2217         done.append(m_jit.jump());
2218
2219         isInteger.link(&m_jit);
2220         m_jit.convertInt32ToDouble(op1GPR, resultFPR);
2221         done.link(&m_jit);
2222 #else // USE(JSVALUE64) -> this is the 32_64 case
2223         FPRTemporary temp(this);
2224
2225         GPRReg op1TagGPR = op1.tagGPR();
2226         GPRReg op1PayloadGPR = op1.payloadGPR();
2227         FPRReg tempFPR = temp.fpr();
2228         FPRReg resultFPR = result.fpr();
2229         JITCompiler::JumpList done;
2230
2231         JITCompiler::Jump isInteger = m_jit.branch32(
2232             MacroAssembler::Equal, op1TagGPR, TrustedImm32(JSValue::Int32Tag));
2233
2234         if (node->child1().useKind() == NotCellUse) {
2235             JITCompiler::Jump isNumber = m_jit.branch32(JITCompiler::Below, op1TagGPR, JITCompiler::TrustedImm32(JSValue::LowestTag + 1));
2236             JITCompiler::Jump isUndefined = m_jit.branch32(JITCompiler::Equal, op1TagGPR, TrustedImm32(JSValue::UndefinedTag));
2237
2238             static const double zero = 0;
2239             m_jit.loadDouble(MacroAssembler::TrustedImmPtr(&zero), resultFPR);
2240
2241             JITCompiler::Jump isNull = m_jit.branch32(JITCompiler::Equal, op1TagGPR, TrustedImm32(JSValue::NullTag));
2242             done.append(isNull);
2243
2244             DFG_TYPE_CHECK(JSValueRegs(op1TagGPR, op1PayloadGPR), node->child1(), ~SpecCell, m_jit.branch32(JITCompiler::NotEqual, op1TagGPR, TrustedImm32(JSValue::BooleanTag)));
2245
2246             JITCompiler::Jump isFalse = m_jit.branchTest32(JITCompiler::Zero, op1PayloadGPR, TrustedImm32(1));
2247             static const double one = 1;
2248             m_jit.loadDouble(MacroAssembler::TrustedImmPtr(&one), resultFPR);
2249             done.append(isFalse);
2250
2251             isUndefined.link(&m_jit);
2252             static const double NaN = PNaN;
2253             m_jit.loadDouble(MacroAssembler::TrustedImmPtr(&NaN), resultFPR);
2254             done.append(m_jit.jump());
2255
2256             isNumber.link(&m_jit);
2257         } else if (needsTypeCheck(node->child1(), SpecBytecodeNumber)) {
2258             typeCheck(
2259                 JSValueRegs(op1TagGPR, op1PayloadGPR), node->child1(), SpecBytecodeNumber,
2260                 m_jit.branch32(MacroAssembler::AboveOrEqual, op1TagGPR, TrustedImm32(JSValue::LowestTag)));
2261         }
2262
2263         unboxDouble(op1TagGPR, op1PayloadGPR, resultFPR, tempFPR);
2264         done.append(m_jit.jump());
2265
2266         isInteger.link(&m_jit);
2267         m_jit.convertInt32ToDouble(op1PayloadGPR, resultFPR);
2268         done.link(&m_jit);
2269 #endif // USE(JSVALUE64)
2270
2271         doubleResult(resultFPR, node);
2272         return;
2273     }
2274
2275 #if USE(JSVALUE64)
2276     case Int52RepUse: {
2277         SpeculateStrictInt52Operand value(this, node->child1());
2278         FPRTemporary result(this);
2279
2280         GPRReg valueGPR = value.gpr();
2281         FPRReg resultFPR = result.fpr();
2282
2283         m_jit.convertInt64ToDouble(valueGPR, resultFPR);
2284
2285         doubleResult(resultFPR, node);
2286         return;
2287     }
2288 #endif // USE(JSVALUE64)
2289
2290     default:
2291         RELEASE_ASSERT_NOT_REACHED();
2292         return;
2293     }
2294 }
2295
2296 void SpeculativeJIT::compileValueRep(Node* node)
2297 {
2298     switch (node->child1().useKind()) {
2299     case DoubleRepUse: {
2300         SpeculateDoubleOperand value(this, node->child1());
2301         JSValueRegsTemporary result(this);
2302
2303         FPRReg valueFPR = value.fpr();
2304         JSValueRegs resultRegs = result.regs();
2305
2306         // It's very tempting to in-place filter the value to indicate that it's not impure NaN
2307         // anymore. Unfortunately, this would be unsound. If it's a GetLocal or if the value was
2308         // subject to a prior SetLocal, filtering the value would imply that the corresponding
2309         // local was purified.
2310         if (needsTypeCheck(node->child1(), ~SpecDoubleImpureNaN))
2311             m_jit.purifyNaN(valueFPR);
2312
2313         boxDouble(valueFPR, resultRegs);
2314
2315         jsValueResult(resultRegs, node);
2316         return;
2317     }
2318
2319 #if USE(JSVALUE64)
2320     case Int52RepUse: {
2321         SpeculateStrictInt52Operand value(this, node->child1());
2322         GPRTemporary result(this);
2323
2324         GPRReg valueGPR = value.gpr();
2325         GPRReg resultGPR = result.gpr();
2326
2327         boxInt52(valueGPR, resultGPR, DataFormatStrictInt52);
2328
2329         jsValueResult(resultGPR, node);
2330         return;
2331     }
2332 #endif // USE(JSVALUE64)
2333
2334     default:
2335         RELEASE_ASSERT_NOT_REACHED();
2336         return;
2337     }
2338 }
2339
2340 static double clampDoubleToByte(double d)
2341 {
2342     d += 0.5;
2343     if (!(d > 0))
2344         d = 0;
2345     else if (d > 255)
2346         d = 255;
2347     return d;
2348 }
2349
2350 static void compileClampIntegerToByte(JITCompiler& jit, GPRReg result)
2351 {
2352     MacroAssembler::Jump inBounds = jit.branch32(MacroAssembler::BelowOrEqual, result, JITCompiler::TrustedImm32(0xff));
2353     MacroAssembler::Jump tooBig = jit.branch32(MacroAssembler::GreaterThan, result, JITCompiler::TrustedImm32(0xff));
2354     jit.xorPtr(result, result);
2355     MacroAssembler::Jump clamped = jit.jump();
2356     tooBig.link(&jit);
2357     jit.move(JITCompiler::TrustedImm32(255), result);
2358     clamped.link(&jit);
2359     inBounds.link(&jit);
2360 }
2361
2362 static void compileClampDoubleToByte(JITCompiler& jit, GPRReg result, FPRReg source, FPRReg scratch)
2363 {
2364     // Unordered compare so we pick up NaN
2365     static const double zero = 0;
2366     static const double byteMax = 255;
2367     static const double half = 0.5;
2368     jit.loadDouble(MacroAssembler::TrustedImmPtr(&zero), scratch);
2369     MacroAssembler::Jump tooSmall = jit.branchDouble(MacroAssembler::DoubleLessThanOrEqualOrUnordered, source, scratch);
2370     jit.loadDouble(MacroAssembler::TrustedImmPtr(&byteMax), scratch);
2371     MacroAssembler::Jump tooBig = jit.branchDouble(MacroAssembler::DoubleGreaterThan, source, scratch);
2372
2373     jit.loadDouble(MacroAssembler::TrustedImmPtr(&half), scratch);
2374     // FIXME: This should probably just use a floating point round!
2375     // https://bugs.webkit.org/show_bug.cgi?id=72054
2376     jit.addDouble(source, scratch);
2377     jit.truncateDoubleToInt32(scratch, result);
2378     MacroAssembler::Jump truncatedInt = jit.jump();
2379
2380     tooSmall.link(&jit);
2381     jit.xorPtr(result, result);
2382     MacroAssembler::Jump zeroed = jit.jump();
2383
2384     tooBig.link(&jit);
2385     jit.move(JITCompiler::TrustedImm32(255), result);
2386
2387     truncatedInt.link(&jit);
2388     zeroed.link(&jit);
2389
2390 }
2391
2392 JITCompiler::Jump SpeculativeJIT::jumpForTypedArrayOutOfBounds(Node* node, GPRReg baseGPR, GPRReg indexGPR)
2393 {
2394     if (node->op() == PutByValAlias)
2395         return JITCompiler::Jump();
2396     JSArrayBufferView* view = m_jit.graph().tryGetFoldableView(
2397         m_state.forNode(m_jit.graph().child(node, 0)).m_value, node->arrayMode());
2398     if (view) {
2399         uint32_t length = view->length();
2400         Node* indexNode = m_jit.graph().child(node, 1).node();
2401         if (indexNode->isInt32Constant() && indexNode->asUInt32() < length)
2402             return JITCompiler::Jump();
2403         return m_jit.branch32(
2404             MacroAssembler::AboveOrEqual, indexGPR, MacroAssembler::Imm32(length));
2405     }
2406     return m_jit.branch32(
2407         MacroAssembler::AboveOrEqual, indexGPR,
2408         MacroAssembler::Address(baseGPR, JSArrayBufferView::offsetOfLength()));
2409 }
2410
2411 void SpeculativeJIT::emitTypedArrayBoundsCheck(Node* node, GPRReg baseGPR, GPRReg indexGPR)
2412 {
2413     JITCompiler::Jump jump = jumpForTypedArrayOutOfBounds(node, baseGPR, indexGPR);
2414     if (!jump.isSet())
2415         return;
2416     speculationCheck(OutOfBounds, JSValueRegs(), 0, jump);
2417 }
2418
2419 void SpeculativeJIT::compileGetByValOnIntTypedArray(Node* node, TypedArrayType type)
2420 {
2421     ASSERT(isInt(type));
2422
2423     SpeculateCellOperand base(this, node->child1());
2424     SpeculateStrictInt32Operand property(this, node->child2());
2425     StorageOperand storage(this, node->child3());
2426
2427     GPRReg baseReg = base.gpr();
2428     GPRReg propertyReg = property.gpr();
2429     GPRReg storageReg = storage.gpr();
2430
2431     GPRTemporary result(this);
2432     GPRReg resultReg = result.gpr();
2433
2434     ASSERT(node->arrayMode().alreadyChecked(m_jit.graph(), node, m_state.forNode(node->child1())));
2435
2436     emitTypedArrayBoundsCheck(node, baseReg, propertyReg);
2437     switch (elementSize(type)) {
2438     case 1:
2439         if (isSigned(type))
2440             m_jit.load8SignedExtendTo32(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesOne), resultReg);
2441         else
2442             m_jit.load8(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesOne), resultReg);
2443         break;
2444     case 2:
2445         if (isSigned(type))
2446             m_jit.load16SignedExtendTo32(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesTwo), resultReg);
2447         else
2448             m_jit.load16(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesTwo), resultReg);
2449         break;
2450     case 4:
2451         m_jit.load32(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesFour), resultReg);
2452         break;
2453     default:
2454         CRASH();
2455     }
2456     if (elementSize(type) < 4 || isSigned(type)) {
2457         int32Result(resultReg, node);
2458         return;
2459     }
2460
2461     ASSERT(elementSize(type) == 4 && !isSigned(type));
2462     if (node->shouldSpeculateInt32()) {
2463         speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branch32(MacroAssembler::LessThan, resultReg, TrustedImm32(0)));
2464         int32Result(resultReg, node);
2465         return;
2466     }
2467
2468 #if USE(JSVALUE64)
2469     if (node->shouldSpeculateMachineInt()) {
2470         m_jit.zeroExtend32ToPtr(resultReg, resultReg);
2471         strictInt52Result(resultReg, node);
2472         return;
2473     }
2474 #endif
2475
2476     FPRTemporary fresult(this);
2477     m_jit.convertInt32ToDouble(resultReg, fresult.fpr());
2478     JITCompiler::Jump positive = m_jit.branch32(MacroAssembler::GreaterThanOrEqual, resultReg, TrustedImm32(0));
2479     m_jit.addDouble(JITCompiler::AbsoluteAddress(&AssemblyHelpers::twoToThe32), fresult.fpr());
2480     positive.link(&m_jit);
2481     doubleResult(fresult.fpr(), node);
2482 }
2483
2484 void SpeculativeJIT::compilePutByValForIntTypedArray(GPRReg base, GPRReg property, Node* node, TypedArrayType type)
2485 {
2486     ASSERT(isInt(type));
2487
2488     StorageOperand storage(this, m_jit.graph().varArgChild(node, 3));
2489     GPRReg storageReg = storage.gpr();
2490
2491     Edge valueUse = m_jit.graph().varArgChild(node, 2);
2492
2493     GPRTemporary value;
2494     GPRReg valueGPR = InvalidGPRReg;
2495
2496     if (valueUse->isConstant()) {
2497         JSValue jsValue = valueUse->asJSValue();
2498         if (!jsValue.isNumber()) {
2499             terminateSpeculativeExecution(Uncountable, JSValueRegs(), 0);
2500             noResult(node);
2501             return;
2502         }
2503         double d = jsValue.asNumber();
2504         if (isClamped(type)) {
2505             ASSERT(elementSize(type) == 1);
2506             d = clampDoubleToByte(d);
2507         }
2508         GPRTemporary scratch(this);
2509         GPRReg scratchReg = scratch.gpr();
2510         m_jit.move(Imm32(toInt32(d)), scratchReg);
2511         value.adopt(scratch);
2512         valueGPR = scratchReg;
2513     } else {
2514         switch (valueUse.useKind()) {
2515         case Int32Use: {
2516             SpeculateInt32Operand valueOp(this, valueUse);
2517             GPRTemporary scratch(this);
2518             GPRReg scratchReg = scratch.gpr();
2519             m_jit.move(valueOp.gpr(), scratchReg);
2520             if (isClamped(type)) {
2521                 ASSERT(elementSize(type) == 1);
2522                 compileClampIntegerToByte(m_jit, scratchReg);
2523             }
2524             value.adopt(scratch);
2525             valueGPR = scratchReg;
2526             break;
2527         }
2528
2529 #if USE(JSVALUE64)
2530         case Int52RepUse: {
2531             SpeculateStrictInt52Operand valueOp(this, valueUse);
2532             GPRTemporary scratch(this);
2533             GPRReg scratchReg = scratch.gpr();
2534             m_jit.move(valueOp.gpr(), scratchReg);
2535             if (isClamped(type)) {
2536                 ASSERT(elementSize(type) == 1);
2537                 MacroAssembler::Jump inBounds = m_jit.branch64(
2538                     MacroAssembler::BelowOrEqual, scratchReg, JITCompiler::TrustedImm64(0xff));
2539                 MacroAssembler::Jump tooBig = m_jit.branch64(
2540                     MacroAssembler::GreaterThan, scratchReg, JITCompiler::TrustedImm64(0xff));
2541                 m_jit.move(TrustedImm32(0), scratchReg);
2542                 MacroAssembler::Jump clamped = m_jit.jump();
2543                 tooBig.link(&m_jit);
2544                 m_jit.move(JITCompiler::TrustedImm32(255), scratchReg);
2545                 clamped.link(&m_jit);
2546                 inBounds.link(&m_jit);
2547             }
2548             value.adopt(scratch);
2549             valueGPR = scratchReg;
2550             break;
2551         }
2552 #endif // USE(JSVALUE64)
2553
2554         case DoubleRepUse: {
2555             if (isClamped(type)) {
2556                 ASSERT(elementSize(type) == 1);
2557                 SpeculateDoubleOperand valueOp(this, valueUse);
2558                 GPRTemporary result(this);
2559                 FPRTemporary floatScratch(this);
2560                 FPRReg fpr = valueOp.fpr();
2561                 GPRReg gpr = result.gpr();
2562                 compileClampDoubleToByte(m_jit, gpr, fpr, floatScratch.fpr());
2563                 value.adopt(result);
2564                 valueGPR = gpr;
2565             } else {
2566                 SpeculateDoubleOperand valueOp(this, valueUse);
2567                 GPRTemporary result(this);
2568                 FPRReg fpr = valueOp.fpr();
2569                 GPRReg gpr = result.gpr();
2570                 MacroAssembler::Jump notNaN = m_jit.branchDouble(MacroAssembler::DoubleEqual, fpr, fpr);
2571                 m_jit.xorPtr(gpr, gpr);
2572                 MacroAssembler::Jump fixed = m_jit.jump();
2573                 notNaN.link(&m_jit);
2574
2575                 MacroAssembler::Jump failed = m_jit.branchTruncateDoubleToInt32(
2576                     fpr, gpr, MacroAssembler::BranchIfTruncateFailed);
2577
2578                 addSlowPathGenerator(slowPathCall(failed, this, toInt32, gpr, fpr, NeedToSpill, ExceptionCheckRequirement::CheckNotNeeded));
2579
2580                 fixed.link(&m_jit);
2581                 value.adopt(result);
2582                 valueGPR = gpr;
2583             }
2584             break;
2585         }
2586
2587         default:
2588             RELEASE_ASSERT_NOT_REACHED();
2589             break;
2590         }
2591     }
2592
2593     ASSERT_UNUSED(valueGPR, valueGPR != property);
2594     ASSERT(valueGPR != base);
2595     ASSERT(valueGPR != storageReg);
2596     MacroAssembler::Jump outOfBounds = jumpForTypedArrayOutOfBounds(node, base, property);
2597     if (node->arrayMode().isInBounds() && outOfBounds.isSet()) {
2598         speculationCheck(OutOfBounds, JSValueSource(), 0, outOfBounds);
2599         outOfBounds = MacroAssembler::Jump();
2600     }
2601
2602     switch (elementSize(type)) {
2603     case 1:
2604         m_jit.store8(value.gpr(), MacroAssembler::BaseIndex(storageReg, property, MacroAssembler::TimesOne));
2605         break;
2606     case 2:
2607         m_jit.store16(value.gpr(), MacroAssembler::BaseIndex(storageReg, property, MacroAssembler::TimesTwo));
2608         break;
2609     case 4:
2610         m_jit.store32(value.gpr(), MacroAssembler::BaseIndex(storageReg, property, MacroAssembler::TimesFour));
2611         break;
2612     default:
2613         CRASH();
2614     }
2615     if (outOfBounds.isSet())
2616         outOfBounds.link(&m_jit);
2617     noResult(node);
2618 }
2619
2620 void SpeculativeJIT::compileGetByValOnFloatTypedArray(Node* node, TypedArrayType type)
2621 {
2622     ASSERT(isFloat(type));
2623
2624     SpeculateCellOperand base(this, node->child1());
2625     SpeculateStrictInt32Operand property(this, node->child2());
2626     StorageOperand storage(this, node->child3());
2627
2628     GPRReg baseReg = base.gpr();
2629     GPRReg propertyReg = property.gpr();
2630     GPRReg storageReg = storage.gpr();
2631
2632     ASSERT(node->arrayMode().alreadyChecked(m_jit.graph(), node, m_state.forNode(node->child1())));
2633
2634     FPRTemporary result(this);
2635     FPRReg resultReg = result.fpr();
2636     emitTypedArrayBoundsCheck(node, baseReg, propertyReg);
2637     switch (elementSize(type)) {
2638     case 4:
2639         m_jit.loadFloat(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesFour), resultReg);
2640         m_jit.convertFloatToDouble(resultReg, resultReg);
2641         break;
2642     case 8: {
2643         m_jit.loadDouble(MacroAssembler::BaseIndex(storageReg, propertyReg, MacroAssembler::TimesEight), resultReg);
2644         break;
2645     }
2646     default:
2647         RELEASE_ASSERT_NOT_REACHED();
2648     }
2649
2650     doubleResult(resultReg, node);
2651 }
2652
2653 void SpeculativeJIT::compilePutByValForFloatTypedArray(GPRReg base, GPRReg property, Node* node, TypedArrayType type)
2654 {
2655     ASSERT(isFloat(type));
2656
2657     StorageOperand storage(this, m_jit.graph().varArgChild(node, 3));
2658     GPRReg storageReg = storage.gpr();
2659
2660     Edge baseUse = m_jit.graph().varArgChild(node, 0);
2661     Edge valueUse = m_jit.graph().varArgChild(node, 2);
2662
2663     SpeculateDoubleOperand valueOp(this, valueUse);
2664     FPRTemporary scratch(this);
2665     FPRReg valueFPR = valueOp.fpr();
2666     FPRReg scratchFPR = scratch.fpr();
2667
2668     ASSERT_UNUSED(baseUse, node->arrayMode().alreadyChecked(m_jit.graph(), node, m_state.forNode(baseUse)));
2669
2670     MacroAssembler::Jump outOfBounds = jumpForTypedArrayOutOfBounds(node, base, property);
2671     if (node->arrayMode().isInBounds() && outOfBounds.isSet()) {
2672         speculationCheck(OutOfBounds, JSValueSource(), 0, outOfBounds);
2673         outOfBounds = MacroAssembler::Jump();
2674     }
2675
2676     switch (elementSize(type)) {
2677     case 4: {
2678         m_jit.moveDouble(valueFPR, scratchFPR);
2679         m_jit.convertDoubleToFloat(valueFPR, scratchFPR);
2680         m_jit.storeFloat(scratchFPR, MacroAssembler::BaseIndex(storageReg, property, MacroAssembler::TimesFour));
2681         break;
2682     }
2683     case 8:
2684         m_jit.storeDouble(valueFPR, MacroAssembler::BaseIndex(storageReg, property, MacroAssembler::TimesEight));
2685         break;
2686     default:
2687         RELEASE_ASSERT_NOT_REACHED();
2688     }
2689     if (outOfBounds.isSet())
2690         outOfBounds.link(&m_jit);
2691     noResult(node);
2692 }
2693
2694 void SpeculativeJIT::compileInstanceOfForObject(Node*, GPRReg valueReg, GPRReg prototypeReg, GPRReg scratchReg, GPRReg scratch2Reg)
2695 {
2696     // Check that prototype is an object.
2697     speculationCheck(BadType, JSValueRegs(), 0, m_jit.branchIfNotObject(prototypeReg));
2698
2699     // Initialize scratchReg with the value being checked.
2700     m_jit.move(valueReg, scratchReg);
2701
2702     // Walk up the prototype chain of the value (in scratchReg), comparing to prototypeReg.
2703     MacroAssembler::Label loop(&m_jit);
2704     m_jit.emitLoadStructure(scratchReg, scratchReg, scratch2Reg);
2705     m_jit.loadPtr(MacroAssembler::Address(scratchReg, Structure::prototypeOffset() + CellPayloadOffset), scratchReg);
2706     MacroAssembler::Jump isInstance = m_jit.branchPtr(MacroAssembler::Equal, scratchReg, prototypeReg);
2707 #if USE(JSVALUE64)
2708     m_jit.branchIfCell(JSValueRegs(scratchReg)).linkTo(loop, &m_jit);
2709 #else
2710     m_jit.branchTestPtr(MacroAssembler::NonZero, scratchReg).linkTo(loop, &m_jit);
2711 #endif
2712
2713     // No match - result is false.
2714 #if USE(JSVALUE64)
2715     m_jit.move(MacroAssembler::TrustedImm64(JSValue::encode(jsBoolean(false))), scratchReg);
2716 #else
2717     m_jit.move(MacroAssembler::TrustedImm32(0), scratchReg);
2718 #endif
2719     MacroAssembler::Jump putResult = m_jit.jump();
2720
2721     isInstance.link(&m_jit);
2722 #if USE(JSVALUE64)
2723     m_jit.move(MacroAssembler::TrustedImm64(JSValue::encode(jsBoolean(true))), scratchReg);
2724 #else
2725     m_jit.move(MacroAssembler::TrustedImm32(1), scratchReg);
2726 #endif
2727
2728     putResult.link(&m_jit);
2729 }
2730
2731 void SpeculativeJIT::compileInstanceOf(Node* node)
2732 {
2733     if (node->child1().useKind() == UntypedUse) {
2734         // It might not be a cell. Speculate less aggressively.
2735         // Or: it might only be used once (i.e. by us), so we get zero benefit
2736         // from speculating any more aggressively than we absolutely need to.
2737
2738         JSValueOperand value(this, node->child1());
2739         SpeculateCellOperand prototype(this, node->child2());
2740         GPRTemporary scratch(this);
2741         GPRTemporary scratch2(this);
2742
2743         GPRReg prototypeReg = prototype.gpr();
2744         GPRReg scratchReg = scratch.gpr();
2745         GPRReg scratch2Reg = scratch2.gpr();
2746
2747         MacroAssembler::Jump isCell = m_jit.branchIfCell(value.jsValueRegs());
2748         GPRReg valueReg = value.jsValueRegs().payloadGPR();
2749         moveFalseTo(scratchReg);
2750
2751         MacroAssembler::Jump done = m_jit.jump();
2752
2753         isCell.link(&m_jit);
2754
2755         compileInstanceOfForObject(node, valueReg, prototypeReg, scratchReg, scratch2Reg);
2756
2757         done.link(&m_jit);
2758
2759         blessedBooleanResult(scratchReg, node);
2760         return;
2761     }
2762
2763     SpeculateCellOperand value(this, node->child1());
2764     SpeculateCellOperand prototype(this, node->child2());
2765
2766     GPRTemporary scratch(this);
2767     GPRTemporary scratch2(this);
2768
2769     GPRReg valueReg = value.gpr();
2770     GPRReg prototypeReg = prototype.gpr();
2771     GPRReg scratchReg = scratch.gpr();
2772     GPRReg scratch2Reg = scratch2.gpr();
2773
2774     compileInstanceOfForObject(node, valueReg, prototypeReg, scratchReg, scratch2Reg);
2775
2776     blessedBooleanResult(scratchReg, node);
2777 }
2778
2779 void SpeculativeJIT::compileAdd(Node* node)
2780 {
2781     switch (node->binaryUseKind()) {
2782     case Int32Use: {
2783         ASSERT(!shouldCheckNegativeZero(node->arithMode()));
2784
2785         if (node->child1()->isInt32Constant()) {
2786             int32_t imm1 = node->child1()->asInt32();
2787             SpeculateInt32Operand op2(this, node->child2());
2788             GPRTemporary result(this);
2789
2790             if (!shouldCheckOverflow(node->arithMode())) {
2791                 m_jit.move(op2.gpr(), result.gpr());
2792                 m_jit.add32(Imm32(imm1), result.gpr());
2793             } else
2794                 speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchAdd32(MacroAssembler::Overflow, op2.gpr(), Imm32(imm1), result.gpr()));
2795
2796             int32Result(result.gpr(), node);
2797             return;
2798         }
2799
2800         if (node->child2()->isInt32Constant()) {
2801             SpeculateInt32Operand op1(this, node->child1());
2802             int32_t imm2 = node->child2()->asInt32();
2803             GPRTemporary result(this);
2804
2805             if (!shouldCheckOverflow(node->arithMode())) {
2806                 m_jit.move(op1.gpr(), result.gpr());
2807                 m_jit.add32(Imm32(imm2), result.gpr());
2808             } else
2809                 speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchAdd32(MacroAssembler::Overflow, op1.gpr(), Imm32(imm2), result.gpr()));
2810
2811             int32Result(result.gpr(), node);
2812             return;
2813         }
2814
2815         SpeculateInt32Operand op1(this, node->child1());
2816         SpeculateInt32Operand op2(this, node->child2());
2817         GPRTemporary result(this, Reuse, op1, op2);
2818
2819         GPRReg gpr1 = op1.gpr();
2820         GPRReg gpr2 = op2.gpr();
2821         GPRReg gprResult = result.gpr();
2822
2823         if (!shouldCheckOverflow(node->arithMode())) {
2824             if (gpr1 == gprResult)
2825                 m_jit.add32(gpr2, gprResult);
2826             else {
2827                 m_jit.move(gpr2, gprResult);
2828                 m_jit.add32(gpr1, gprResult);
2829             }
2830         } else {
2831             MacroAssembler::Jump check = m_jit.branchAdd32(MacroAssembler::Overflow, gpr1, gpr2, gprResult);
2832
2833             if (gpr1 == gprResult)
2834                 speculationCheck(Overflow, JSValueRegs(), 0, check, SpeculationRecovery(SpeculativeAdd, gprResult, gpr2));
2835             else if (gpr2 == gprResult)
2836                 speculationCheck(Overflow, JSValueRegs(), 0, check, SpeculationRecovery(SpeculativeAdd, gprResult, gpr1));
2837             else
2838                 speculationCheck(Overflow, JSValueRegs(), 0, check);
2839         }
2840
2841         int32Result(gprResult, node);
2842         return;
2843     }
2844
2845 #if USE(JSVALUE64)
2846     case Int52RepUse: {
2847         ASSERT(shouldCheckOverflow(node->arithMode()));
2848         ASSERT(!shouldCheckNegativeZero(node->arithMode()));
2849
2850         // Will we need an overflow check? If we can prove that neither input can be
2851         // Int52 then the overflow check will not be necessary.
2852         if (!m_state.forNode(node->child1()).couldBeType(SpecInt52)
2853             && !m_state.forNode(node->child2()).couldBeType(SpecInt52)) {
2854             SpeculateWhicheverInt52Operand op1(this, node->child1());
2855             SpeculateWhicheverInt52Operand op2(this, node->child2(), op1);
2856             GPRTemporary result(this, Reuse, op1);
2857             m_jit.move(op1.gpr(), result.gpr());
2858             m_jit.add64(op2.gpr(), result.gpr());
2859             int52Result(result.gpr(), node, op1.format());
2860             return;
2861         }
2862
2863         SpeculateInt52Operand op1(this, node->child1());
2864         SpeculateInt52Operand op2(this, node->child2());
2865         GPRTemporary result(this);
2866         m_jit.move(op1.gpr(), result.gpr());
2867         speculationCheck(
2868             Int52Overflow, JSValueRegs(), 0,
2869             m_jit.branchAdd64(MacroAssembler::Overflow, op2.gpr(), result.gpr()));
2870         int52Result(result.gpr(), node);
2871         return;
2872     }
2873 #endif // USE(JSVALUE64)
2874
2875     case DoubleRepUse: {
2876         SpeculateDoubleOperand op1(this, node->child1());
2877         SpeculateDoubleOperand op2(this, node->child2());
2878         FPRTemporary result(this, op1, op2);
2879
2880         FPRReg reg1 = op1.fpr();
2881         FPRReg reg2 = op2.fpr();
2882         m_jit.addDouble(reg1, reg2, result.fpr());
2883
2884         doubleResult(result.fpr(), node);
2885         return;
2886     }
2887
2888     default:
2889         RELEASE_ASSERT_NOT_REACHED();
2890         break;
2891     }
2892 }
2893
2894 void SpeculativeJIT::compileMakeRope(Node* node)
2895 {
2896     ASSERT(node->child1().useKind() == KnownStringUse);
2897     ASSERT(node->child2().useKind() == KnownStringUse);
2898     ASSERT(!node->child3() || node->child3().useKind() == KnownStringUse);
2899
2900     SpeculateCellOperand op1(this, node->child1());
2901     SpeculateCellOperand op2(this, node->child2());
2902     SpeculateCellOperand op3(this, node->child3());
2903     GPRTemporary result(this);
2904     GPRTemporary allocator(this);
2905     GPRTemporary scratch(this);
2906
2907     GPRReg opGPRs[3];
2908     unsigned numOpGPRs;
2909     opGPRs[0] = op1.gpr();
2910     opGPRs[1] = op2.gpr();
2911     if (node->child3()) {
2912         opGPRs[2] = op3.gpr();
2913         numOpGPRs = 3;
2914     } else {
2915         opGPRs[2] = InvalidGPRReg;
2916         numOpGPRs = 2;
2917     }
2918     GPRReg resultGPR = result.gpr();
2919     GPRReg allocatorGPR = allocator.gpr();
2920     GPRReg scratchGPR = scratch.gpr();
2921
2922     JITCompiler::JumpList slowPath;
2923     MarkedAllocator& markedAllocator = m_jit.vm()->heap.allocatorForObjectWithDestructor(sizeof(JSRopeString));
2924     m_jit.move(TrustedImmPtr(&markedAllocator), allocatorGPR);
2925     emitAllocateJSCell(resultGPR, allocatorGPR, TrustedImmPtr(m_jit.vm()->stringStructure.get()), scratchGPR, slowPath);
2926
2927     m_jit.storePtr(TrustedImmPtr(0), JITCompiler::Address(resultGPR, JSString::offsetOfValue()));
2928     for (unsigned i = 0; i < numOpGPRs; ++i)
2929         m_jit.storePtr(opGPRs[i], JITCompiler::Address(resultGPR, JSRopeString::offsetOfFibers() + sizeof(WriteBarrier<JSString>) * i));
2930     for (unsigned i = numOpGPRs; i < JSRopeString::s_maxInternalRopeLength; ++i)
2931         m_jit.storePtr(TrustedImmPtr(0), JITCompiler::Address(resultGPR, JSRopeString::offsetOfFibers() + sizeof(WriteBarrier<JSString>) * i));
2932     m_jit.load32(JITCompiler::Address(opGPRs[0], JSString::offsetOfFlags()), scratchGPR);
2933     m_jit.load32(JITCompiler::Address(opGPRs[0], JSString::offsetOfLength()), allocatorGPR);
2934     if (!ASSERT_DISABLED) {
2935         JITCompiler::Jump ok = m_jit.branch32(
2936             JITCompiler::GreaterThanOrEqual, allocatorGPR, TrustedImm32(0));
2937         m_jit.abortWithReason(DFGNegativeStringLength);
2938         ok.link(&m_jit);
2939     }
2940     for (unsigned i = 1; i < numOpGPRs; ++i) {
2941         m_jit.and32(JITCompiler::Address(opGPRs[i], JSString::offsetOfFlags()), scratchGPR);
2942         speculationCheck(
2943             Uncountable, JSValueSource(), nullptr,
2944             m_jit.branchAdd32(
2945                 JITCompiler::Overflow,
2946                 JITCompiler::Address(opGPRs[i], JSString::offsetOfLength()), allocatorGPR));
2947     }
2948     m_jit.and32(JITCompiler::TrustedImm32(JSString::Is8Bit), scratchGPR);
2949     m_jit.store32(scratchGPR, JITCompiler::Address(resultGPR, JSString::offsetOfFlags()));
2950     if (!ASSERT_DISABLED) {
2951         JITCompiler::Jump ok = m_jit.branch32(
2952             JITCompiler::GreaterThanOrEqual, allocatorGPR, TrustedImm32(0));
2953         m_jit.abortWithReason(DFGNegativeStringLength);
2954         ok.link(&m_jit);
2955     }
2956     m_jit.store32(allocatorGPR, JITCompiler::Address(resultGPR, JSString::offsetOfLength()));
2957
2958     switch (numOpGPRs) {
2959     case 2:
2960         addSlowPathGenerator(slowPathCall(
2961             slowPath, this, operationMakeRope2, resultGPR, opGPRs[0], opGPRs[1]));
2962         break;
2963     case 3:
2964         addSlowPathGenerator(slowPathCall(
2965             slowPath, this, operationMakeRope3, resultGPR, opGPRs[0], opGPRs[1], opGPRs[2]));
2966         break;
2967     default:
2968         RELEASE_ASSERT_NOT_REACHED();
2969         break;
2970     }
2971
2972     cellResult(resultGPR, node);
2973 }
2974
2975 void SpeculativeJIT::compileArithClz32(Node* node)
2976 {
2977     ASSERT_WITH_MESSAGE(node->child1().useKind() == Int32Use || node->child1().useKind() == KnownInt32Use, "The Fixup phase should have enforced a Int32 operand.");
2978     SpeculateInt32Operand value(this, node->child1());
2979     GPRTemporary result(this, Reuse, value);
2980     GPRReg valueReg = value.gpr();
2981     GPRReg resultReg = result.gpr();
2982     m_jit.countLeadingZeros32(valueReg, resultReg);
2983     int32Result(resultReg, node);
2984 }
2985
2986 void SpeculativeJIT::compileArithSub(Node* node)
2987 {
2988     switch (node->binaryUseKind()) {
2989     case Int32Use: {
2990         ASSERT(!shouldCheckNegativeZero(node->arithMode()));
2991
2992         if (node->child2()->isInt32Constant()) {
2993             SpeculateInt32Operand op1(this, node->child1());
2994             int32_t imm2 = node->child2()->asInt32();
2995             GPRTemporary result(this);
2996
2997             if (!shouldCheckOverflow(node->arithMode())) {
2998                 m_jit.move(op1.gpr(), result.gpr());
2999                 m_jit.sub32(Imm32(imm2), result.gpr());
3000             } else {
3001                 GPRTemporary scratch(this);
3002                 speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchSub32(MacroAssembler::Overflow, op1.gpr(), Imm32(imm2), result.gpr(), scratch.gpr()));
3003             }
3004
3005             int32Result(result.gpr(), node);
3006             return;
3007         }
3008
3009         if (node->child1()->isInt32Constant()) {
3010             int32_t imm1 = node->child1()->asInt32();
3011             SpeculateInt32Operand op2(this, node->child2());
3012             GPRTemporary result(this);
3013
3014             m_jit.move(Imm32(imm1), result.gpr());
3015             if (!shouldCheckOverflow(node->arithMode()))
3016                 m_jit.sub32(op2.gpr(), result.gpr());
3017             else
3018                 speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchSub32(MacroAssembler::Overflow, op2.gpr(), result.gpr()));
3019
3020             int32Result(result.gpr(), node);
3021             return;
3022         }
3023
3024         SpeculateInt32Operand op1(this, node->child1());
3025         SpeculateInt32Operand op2(this, node->child2());
3026         GPRTemporary result(this);
3027
3028         if (!shouldCheckOverflow(node->arithMode())) {
3029             m_jit.move(op1.gpr(), result.gpr());
3030             m_jit.sub32(op2.gpr(), result.gpr());
3031         } else
3032             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchSub32(MacroAssembler::Overflow, op1.gpr(), op2.gpr(), result.gpr()));
3033
3034         int32Result(result.gpr(), node);
3035         return;
3036     }
3037
3038 #if USE(JSVALUE64)
3039     case Int52RepUse: {
3040         ASSERT(shouldCheckOverflow(node->arithMode()));
3041         ASSERT(!shouldCheckNegativeZero(node->arithMode()));
3042
3043         // Will we need an overflow check? If we can prove that neither input can be
3044         // Int52 then the overflow check will not be necessary.
3045         if (!m_state.forNode(node->child1()).couldBeType(SpecInt52)
3046             && !m_state.forNode(node->child2()).couldBeType(SpecInt52)) {
3047             SpeculateWhicheverInt52Operand op1(this, node->child1());
3048             SpeculateWhicheverInt52Operand op2(this, node->child2(), op1);
3049             GPRTemporary result(this, Reuse, op1);
3050             m_jit.move(op1.gpr(), result.gpr());
3051             m_jit.sub64(op2.gpr(), result.gpr());
3052             int52Result(result.gpr(), node, op1.format());
3053             return;
3054         }
3055
3056         SpeculateInt52Operand op1(this, node->child1());
3057         SpeculateInt52Operand op2(this, node->child2());
3058         GPRTemporary result(this);
3059         m_jit.move(op1.gpr(), result.gpr());
3060         speculationCheck(
3061             Int52Overflow, JSValueRegs(), 0,
3062             m_jit.branchSub64(MacroAssembler::Overflow, op2.gpr(), result.gpr()));
3063         int52Result(result.gpr(), node);
3064         return;
3065     }
3066 #endif // USE(JSVALUE64)
3067
3068     case DoubleRepUse: {
3069         SpeculateDoubleOperand op1(this, node->child1());
3070         SpeculateDoubleOperand op2(this, node->child2());
3071         FPRTemporary result(this, op1);
3072
3073         FPRReg reg1 = op1.fpr();
3074         FPRReg reg2 = op2.fpr();
3075         m_jit.subDouble(reg1, reg2, result.fpr());
3076
3077         doubleResult(result.fpr(), node);
3078         return;
3079     }
3080
3081     default:
3082         RELEASE_ASSERT_NOT_REACHED();
3083         return;
3084     }
3085 }
3086
3087 void SpeculativeJIT::compileArithNegate(Node* node)
3088 {
3089     switch (node->child1().useKind()) {
3090     case Int32Use: {
3091         SpeculateInt32Operand op1(this, node->child1());
3092         GPRTemporary result(this);
3093
3094         m_jit.move(op1.gpr(), result.gpr());
3095
3096         // Note: there is no notion of being not used as a number, but someone
3097         // caring about negative zero.
3098
3099         if (!shouldCheckOverflow(node->arithMode()))
3100             m_jit.neg32(result.gpr());
3101         else if (!shouldCheckNegativeZero(node->arithMode()))
3102             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchNeg32(MacroAssembler::Overflow, result.gpr()));
3103         else {
3104             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(MacroAssembler::Zero, result.gpr(), TrustedImm32(0x7fffffff)));
3105             m_jit.neg32(result.gpr());
3106         }
3107
3108         int32Result(result.gpr(), node);
3109         return;
3110     }
3111
3112 #if USE(JSVALUE64)
3113     case Int52RepUse: {
3114         ASSERT(shouldCheckOverflow(node->arithMode()));
3115
3116         if (!m_state.forNode(node->child1()).couldBeType(SpecInt52)) {
3117             SpeculateWhicheverInt52Operand op1(this, node->child1());
3118             GPRTemporary result(this);
3119             GPRReg op1GPR = op1.gpr();
3120             GPRReg resultGPR = result.gpr();
3121             m_jit.move(op1GPR, resultGPR);
3122             m_jit.neg64(resultGPR);
3123             if (shouldCheckNegativeZero(node->arithMode())) {
3124                 speculationCheck(
3125                     NegativeZero, JSValueRegs(), 0,
3126                     m_jit.branchTest64(MacroAssembler::Zero, resultGPR));
3127             }
3128             int52Result(resultGPR, node, op1.format());
3129             return;
3130         }
3131
3132         SpeculateInt52Operand op1(this, node->child1());
3133         GPRTemporary result(this);
3134         GPRReg op1GPR = op1.gpr();
3135         GPRReg resultGPR = result.gpr();
3136         m_jit.move(op1GPR, resultGPR);
3137         speculationCheck(
3138             Int52Overflow, JSValueRegs(), 0,
3139             m_jit.branchNeg64(MacroAssembler::Overflow, resultGPR));
3140         if (shouldCheckNegativeZero(node->arithMode())) {
3141             speculationCheck(
3142                 NegativeZero, JSValueRegs(), 0,
3143                 m_jit.branchTest64(MacroAssembler::Zero, resultGPR));
3144         }
3145         int52Result(resultGPR, node);
3146         return;
3147     }
3148 #endif // USE(JSVALUE64)
3149
3150     case DoubleRepUse: {
3151         SpeculateDoubleOperand op1(this, node->child1());
3152         FPRTemporary result(this);
3153
3154         m_jit.negateDouble(op1.fpr(), result.fpr());
3155
3156         doubleResult(result.fpr(), node);
3157         return;
3158     }
3159
3160     default:
3161         RELEASE_ASSERT_NOT_REACHED();
3162         return;
3163     }
3164 }
3165 void SpeculativeJIT::compileArithMul(Node* node)
3166 {
3167     switch (node->binaryUseKind()) {
3168     case Int32Use: {
3169         SpeculateInt32Operand op1(this, node->child1());
3170         SpeculateInt32Operand op2(this, node->child2());
3171         GPRTemporary result(this);
3172
3173         GPRReg reg1 = op1.gpr();
3174         GPRReg reg2 = op2.gpr();
3175
3176         // We can perform truncated multiplications if we get to this point, because if the
3177         // fixup phase could not prove that it would be safe, it would have turned us into
3178         // a double multiplication.
3179         if (!shouldCheckOverflow(node->arithMode())) {
3180             m_jit.move(reg1, result.gpr());
3181             m_jit.mul32(reg2, result.gpr());
3182         } else {
3183             speculationCheck(
3184                 Overflow, JSValueRegs(), 0,
3185                 m_jit.branchMul32(MacroAssembler::Overflow, reg1, reg2, result.gpr()));
3186         }
3187
3188         // Check for negative zero, if the users of this node care about such things.
3189         if (shouldCheckNegativeZero(node->arithMode())) {
3190             MacroAssembler::Jump resultNonZero = m_jit.branchTest32(MacroAssembler::NonZero, result.gpr());
3191             speculationCheck(NegativeZero, JSValueRegs(), 0, m_jit.branch32(MacroAssembler::LessThan, reg1, TrustedImm32(0)));
3192             speculationCheck(NegativeZero, JSValueRegs(), 0, m_jit.branch32(MacroAssembler::LessThan, reg2, TrustedImm32(0)));
3193             resultNonZero.link(&m_jit);
3194         }
3195
3196         int32Result(result.gpr(), node);
3197         return;
3198     }
3199
3200 #if USE(JSVALUE64)
3201     case Int52RepUse: {
3202         ASSERT(shouldCheckOverflow(node->arithMode()));
3203
3204         // This is super clever. We want to do an int52 multiplication and check the
3205         // int52 overflow bit. There is no direct hardware support for this, but we do
3206         // have the ability to do an int64 multiplication and check the int64 overflow
3207         // bit. We leverage that. Consider that a, b are int52 numbers inside int64
3208         // registers, with the high 12 bits being sign-extended. We can do:
3209         //
3210         //     (a * (b << 12))
3211         //
3212         // This will give us a left-shifted int52 (value is in high 52 bits, low 16
3213         // bits are zero) plus the int52 overflow bit. I.e. whether this 64-bit
3214         // multiplication overflows is identical to whether the 'a * b' 52-bit
3215         // multiplication overflows.
3216         //
3217         // In our nomenclature, this is:
3218         //
3219         //     strictInt52(a) * int52(b) => int52
3220         //
3221         // That is "strictInt52" means unshifted and "int52" means left-shifted by 16
3222         // bits.
3223         //
3224         // We don't care which of op1 or op2 serves as the left-shifted operand, so
3225         // we just do whatever is more convenient for op1 and have op2 do the
3226         // opposite. This ensures that we do at most one shift.
3227
3228         SpeculateWhicheverInt52Operand op1(this, node->child1());
3229         SpeculateWhicheverInt52Operand op2(this, node->child2(), OppositeShift, op1);
3230         GPRTemporary result(this);
3231
3232         GPRReg op1GPR = op1.gpr();
3233         GPRReg op2GPR = op2.gpr();
3234         GPRReg resultGPR = result.gpr();
3235
3236         m_jit.move(op1GPR, resultGPR);
3237         speculationCheck(
3238             Int52Overflow, JSValueRegs(), 0,
3239             m_jit.branchMul64(MacroAssembler::Overflow, op2GPR, resultGPR));
3240
3241         if (shouldCheckNegativeZero(node->arithMode())) {
3242             MacroAssembler::Jump resultNonZero = m_jit.branchTest64(
3243                 MacroAssembler::NonZero, resultGPR);
3244             speculationCheck(
3245                 NegativeZero, JSValueRegs(), 0,
3246                 m_jit.branch64(MacroAssembler::LessThan, op1GPR, TrustedImm64(0)));
3247             speculationCheck(
3248                 NegativeZero, JSValueRegs(), 0,
3249                 m_jit.branch64(MacroAssembler::LessThan, op2GPR, TrustedImm64(0)));
3250             resultNonZero.link(&m_jit);
3251         }
3252
3253         int52Result(resultGPR, node);
3254         return;
3255     }
3256 #endif // USE(JSVALUE64)
3257
3258     case DoubleRepUse: {
3259         SpeculateDoubleOperand op1(this, node->child1());
3260         SpeculateDoubleOperand op2(this, node->child2());
3261         FPRTemporary result(this, op1, op2);
3262
3263         FPRReg reg1 = op1.fpr();
3264         FPRReg reg2 = op2.fpr();
3265
3266         m_jit.mulDouble(reg1, reg2, result.fpr());
3267
3268         doubleResult(result.fpr(), node);
3269         return;
3270     }
3271
3272     default:
3273         RELEASE_ASSERT_NOT_REACHED();
3274         return;
3275     }
3276 }
3277
3278 void SpeculativeJIT::compileArithDiv(Node* node)
3279 {
3280     switch (node->binaryUseKind()) {
3281     case Int32Use: {
3282 #if CPU(X86) || CPU(X86_64)
3283         SpeculateInt32Operand op1(this, node->child1());
3284         SpeculateInt32Operand op2(this, node->child2());
3285         GPRTemporary eax(this, X86Registers::eax);
3286         GPRTemporary edx(this, X86Registers::edx);
3287         GPRReg op1GPR = op1.gpr();
3288         GPRReg op2GPR = op2.gpr();
3289
3290         GPRReg op2TempGPR;
3291         GPRReg temp;
3292         if (op2GPR == X86Registers::eax || op2GPR == X86Registers::edx) {
3293             op2TempGPR = allocate();
3294             temp = op2TempGPR;
3295         } else {
3296             op2TempGPR = InvalidGPRReg;
3297             if (op1GPR == X86Registers::eax)
3298                 temp = X86Registers::edx;
3299             else
3300                 temp = X86Registers::eax;
3301         }
3302
3303         ASSERT(temp != op1GPR);
3304         ASSERT(temp != op2GPR);
3305
3306         m_jit.add32(JITCompiler::TrustedImm32(1), op2GPR, temp);
3307
3308         JITCompiler::Jump safeDenominator = m_jit.branch32(JITCompiler::Above, temp, JITCompiler::TrustedImm32(1));
3309
3310         JITCompiler::JumpList done;
3311         if (shouldCheckOverflow(node->arithMode())) {
3312             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::Zero, op2GPR));
3313             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branch32(JITCompiler::Equal, op1GPR, TrustedImm32(-2147483647-1)));
3314         } else {
3315             // This is the case where we convert the result to an int after we're done, and we
3316             // already know that the denominator is either -1 or 0. So, if the denominator is
3317             // zero, then the result should be zero. If the denominator is not zero (i.e. it's
3318             // -1) and the numerator is -2^31 then the result should be -2^31. Otherwise we
3319             // are happy to fall through to a normal division, since we're just dividing
3320             // something by negative 1.
3321
3322             JITCompiler::Jump notZero = m_jit.branchTest32(JITCompiler::NonZero, op2GPR);
3323             m_jit.move(TrustedImm32(0), eax.gpr());
3324             done.append(m_jit.jump());
3325
3326             notZero.link(&m_jit);
3327             JITCompiler::Jump notNeg2ToThe31 =
3328                 m_jit.branch32(JITCompiler::NotEqual, op1GPR, TrustedImm32(-2147483647-1));
3329             m_jit.zeroExtend32ToPtr(op1GPR, eax.gpr());
3330             done.append(m_jit.jump());
3331
3332             notNeg2ToThe31.link(&m_jit);
3333         }
3334
3335         safeDenominator.link(&m_jit);
3336
3337         // If the user cares about negative zero, then speculate that we're not about
3338         // to produce negative zero.
3339         if (shouldCheckNegativeZero(node->arithMode())) {
3340             MacroAssembler::Jump numeratorNonZero = m_jit.branchTest32(MacroAssembler::NonZero, op1GPR);
3341             speculationCheck(NegativeZero, JSValueRegs(), 0, m_jit.branch32(MacroAssembler::LessThan, op2GPR, TrustedImm32(0)));
3342             numeratorNonZero.link(&m_jit);
3343         }
3344
3345         if (op2TempGPR != InvalidGPRReg) {
3346             m_jit.move(op2GPR, op2TempGPR);
3347             op2GPR = op2TempGPR;
3348         }
3349
3350         m_jit.move(op1GPR, eax.gpr());
3351         m_jit.assembler().cdq();
3352         m_jit.assembler().idivl_r(op2GPR);
3353
3354         if (op2TempGPR != InvalidGPRReg)
3355             unlock(op2TempGPR);
3356
3357         // Check that there was no remainder. If there had been, then we'd be obligated to
3358         // produce a double result instead.
3359         if (shouldCheckOverflow(node->arithMode()))
3360             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::NonZero, edx.gpr()));
3361
3362         done.link(&m_jit);
3363         int32Result(eax.gpr(), node);
3364 #elif HAVE(ARM_IDIV_INSTRUCTIONS) || CPU(ARM64)
3365         SpeculateInt32Operand op1(this, node->child1());
3366         SpeculateInt32Operand op2(this, node->child2());
3367         GPRReg op1GPR = op1.gpr();
3368         GPRReg op2GPR = op2.gpr();
3369         GPRTemporary quotient(this);
3370         GPRTemporary multiplyAnswer(this);
3371
3372         // If the user cares about negative zero, then speculate that we're not about
3373         // to produce negative zero.
3374         if (shouldCheckNegativeZero(node->arithMode())) {
3375             MacroAssembler::Jump numeratorNonZero = m_jit.branchTest32(MacroAssembler::NonZero, op1GPR);
3376             speculationCheck(NegativeZero, JSValueRegs(), 0, m_jit.branch32(MacroAssembler::LessThan, op2GPR, TrustedImm32(0)));
3377             numeratorNonZero.link(&m_jit);
3378         }
3379
3380         m_jit.assembler().sdiv<32>(quotient.gpr(), op1GPR, op2GPR);
3381
3382         // Check that there was no remainder. If there had been, then we'd be obligated to
3383         // produce a double result instead.
3384         if (shouldCheckOverflow(node->arithMode())) {
3385             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchMul32(JITCompiler::Overflow, quotient.gpr(), op2GPR, multiplyAnswer.gpr()));
3386             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branch32(JITCompiler::NotEqual, multiplyAnswer.gpr(), op1GPR));
3387         }
3388
3389         int32Result(quotient.gpr(), node);
3390 #else
3391         RELEASE_ASSERT_NOT_REACHED();
3392 #endif
3393         break;
3394     }
3395
3396     case DoubleRepUse: {
3397         SpeculateDoubleOperand op1(this, node->child1());
3398         SpeculateDoubleOperand op2(this, node->child2());
3399         FPRTemporary result(this, op1);
3400
3401         FPRReg reg1 = op1.fpr();
3402         FPRReg reg2 = op2.fpr();
3403         m_jit.divDouble(reg1, reg2, result.fpr());
3404
3405         doubleResult(result.fpr(), node);
3406         break;
3407     }
3408
3409     default:
3410         RELEASE_ASSERT_NOT_REACHED();
3411         break;
3412     }
3413 }
3414
3415 void SpeculativeJIT::compileArithMod(Node* node)
3416 {
3417     switch (node->binaryUseKind()) {
3418     case Int32Use: {
3419         // In the fast path, the dividend value could be the final result
3420         // (in case of |dividend| < |divisor|), so we speculate it as strict int32.
3421         SpeculateStrictInt32Operand op1(this, node->child1());
3422
3423         if (node->child2()->isInt32Constant()) {
3424             int32_t divisor = node->child2()->asInt32();
3425             if (divisor > 1 && hasOneBitSet(divisor)) {
3426                 unsigned logarithm = WTF::fastLog2(divisor);
3427                 GPRReg dividendGPR = op1.gpr();
3428                 GPRTemporary result(this);
3429                 GPRReg resultGPR = result.gpr();
3430
3431                 // This is what LLVM generates. It's pretty crazy. Here's my
3432                 // attempt at understanding it.
3433
3434                 // First, compute either divisor - 1, or 0, depending on whether
3435                 // the dividend is negative:
3436                 //
3437                 // If dividend < 0:  resultGPR = divisor - 1
3438                 // If dividend >= 0: resultGPR = 0
3439                 m_jit.move(dividendGPR, resultGPR);
3440                 m_jit.rshift32(TrustedImm32(31), resultGPR);
3441                 m_jit.urshift32(TrustedImm32(32 - logarithm), resultGPR);
3442
3443                 // Add in the dividend, so that:
3444                 //
3445                 // If dividend < 0:  resultGPR = dividend + divisor - 1
3446                 // If dividend >= 0: resultGPR = dividend
3447                 m_jit.add32(dividendGPR, resultGPR);
3448
3449                 // Mask so as to only get the *high* bits. This rounds down
3450                 // (towards negative infinity) resultGPR to the nearest multiple
3451                 // of divisor, so that:
3452                 //
3453                 // If dividend < 0:  resultGPR = floor((dividend + divisor - 1) / divisor)
3454                 // If dividend >= 0: resultGPR = floor(dividend / divisor)
3455                 //
3456                 // Note that this can be simplified to:
3457                 //
3458                 // If dividend < 0:  resultGPR = ceil(dividend / divisor)
3459                 // If dividend >= 0: resultGPR = floor(dividend / divisor)
3460                 //
3461                 // Note that if the dividend is negative, resultGPR will also be negative.
3462                 // Regardless of the sign of dividend, resultGPR will be rounded towards
3463                 // zero, because of how things are conditionalized.
3464                 m_jit.and32(TrustedImm32(-divisor), resultGPR);
3465
3466                 // Subtract resultGPR from dividendGPR, which yields the remainder:
3467                 //
3468                 // resultGPR = dividendGPR - resultGPR
3469                 m_jit.neg32(resultGPR);
3470                 m_jit.add32(dividendGPR, resultGPR);
3471
3472                 if (shouldCheckNegativeZero(node->arithMode())) {
3473                     // Check that we're not about to create negative zero.
3474                     JITCompiler::Jump numeratorPositive = m_jit.branch32(JITCompiler::GreaterThanOrEqual, dividendGPR, TrustedImm32(0));
3475                     speculationCheck(NegativeZero, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::Zero, resultGPR));
3476                     numeratorPositive.link(&m_jit);
3477                 }
3478
3479                 int32Result(resultGPR, node);
3480                 return;
3481             }
3482         }
3483
3484 #if CPU(X86) || CPU(X86_64)
3485         if (node->child2()->isInt32Constant()) {
3486             int32_t divisor = node->child2()->asInt32();
3487             if (divisor && divisor != -1) {
3488                 GPRReg op1Gpr = op1.gpr();
3489
3490                 GPRTemporary eax(this, X86Registers::eax);
3491                 GPRTemporary edx(this, X86Registers::edx);
3492                 GPRTemporary scratch(this);
3493                 GPRReg scratchGPR = scratch.gpr();
3494
3495                 GPRReg op1SaveGPR;
3496                 if (op1Gpr == X86Registers::eax || op1Gpr == X86Registers::edx) {
3497                     op1SaveGPR = allocate();
3498                     ASSERT(op1Gpr != op1SaveGPR);
3499                     m_jit.move(op1Gpr, op1SaveGPR);
3500                 } else
3501                     op1SaveGPR = op1Gpr;
3502                 ASSERT(op1SaveGPR != X86Registers::eax);
3503                 ASSERT(op1SaveGPR != X86Registers::edx);
3504
3505                 m_jit.move(op1Gpr, eax.gpr());
3506                 m_jit.move(TrustedImm32(divisor), scratchGPR);
3507                 m_jit.assembler().cdq();
3508                 m_jit.assembler().idivl_r(scratchGPR);
3509                 if (shouldCheckNegativeZero(node->arithMode())) {
3510                     JITCompiler::Jump numeratorPositive = m_jit.branch32(JITCompiler::GreaterThanOrEqual, op1SaveGPR, TrustedImm32(0));
3511                     speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::Zero, edx.gpr()));
3512                     numeratorPositive.link(&m_jit);
3513                 }
3514
3515                 if (op1SaveGPR != op1Gpr)
3516                     unlock(op1SaveGPR);
3517
3518                 int32Result(edx.gpr(), node);
3519                 return;
3520             }
3521         }
3522 #endif
3523
3524         SpeculateInt32Operand op2(this, node->child2());
3525 #if CPU(X86) || CPU(X86_64)
3526         GPRTemporary eax(this, X86Registers::eax);
3527         GPRTemporary edx(this, X86Registers::edx);
3528         GPRReg op1GPR = op1.gpr();
3529         GPRReg op2GPR = op2.gpr();
3530
3531         GPRReg op2TempGPR;
3532         GPRReg temp;
3533         GPRReg op1SaveGPR;
3534
3535         if (op2GPR == X86Registers::eax || op2GPR == X86Registers::edx) {
3536             op2TempGPR = allocate();
3537             temp = op2TempGPR;
3538         } else {
3539             op2TempGPR = InvalidGPRReg;
3540             if (op1GPR == X86Registers::eax)
3541                 temp = X86Registers::edx;
3542             else
3543                 temp = X86Registers::eax;
3544         }
3545
3546         if (op1GPR == X86Registers::eax || op1GPR == X86Registers::edx) {
3547             op1SaveGPR = allocate();
3548             ASSERT(op1GPR != op1SaveGPR);
3549             m_jit.move(op1GPR, op1SaveGPR);
3550         } else
3551             op1SaveGPR = op1GPR;
3552
3553         ASSERT(temp != op1GPR);
3554         ASSERT(temp != op2GPR);
3555         ASSERT(op1SaveGPR != X86Registers::eax);
3556         ASSERT(op1SaveGPR != X86Registers::edx);
3557
3558         m_jit.add32(JITCompiler::TrustedImm32(1), op2GPR, temp);
3559
3560         JITCompiler::Jump safeDenominator = m_jit.branch32(JITCompiler::Above, temp, JITCompiler::TrustedImm32(1));
3561
3562         JITCompiler::JumpList done;
3563
3564         // FIXME: -2^31 / -1 will actually yield negative zero, so we could have a
3565         // separate case for that. But it probably doesn't matter so much.
3566         if (shouldCheckOverflow(node->arithMode())) {
3567             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::Zero, op2GPR));
3568             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branch32(JITCompiler::Equal, op1GPR, TrustedImm32(-2147483647-1)));
3569         } else {
3570             // This is the case where we convert the result to an int after we're done, and we
3571             // already know that the denominator is either -1 or 0. So, if the denominator is
3572             // zero, then the result should be zero. If the denominator is not zero (i.e. it's
3573             // -1) and the numerator is -2^31 then the result should be 0. Otherwise we are
3574             // happy to fall through to a normal division, since we're just dividing something
3575             // by negative 1.
3576
3577             JITCompiler::Jump notZero = m_jit.branchTest32(JITCompiler::NonZero, op2GPR);
3578             m_jit.move(TrustedImm32(0), edx.gpr());
3579             done.append(m_jit.jump());
3580
3581             notZero.link(&m_jit);
3582             JITCompiler::Jump notNeg2ToThe31 =
3583                 m_jit.branch32(JITCompiler::NotEqual, op1GPR, TrustedImm32(-2147483647-1));
3584             m_jit.move(TrustedImm32(0), edx.gpr());
3585             done.append(m_jit.jump());
3586
3587             notNeg2ToThe31.link(&m_jit);
3588         }
3589
3590         safeDenominator.link(&m_jit);
3591
3592         if (op2TempGPR != InvalidGPRReg) {
3593             m_jit.move(op2GPR, op2TempGPR);
3594             op2GPR = op2TempGPR;
3595         }
3596
3597         m_jit.move(op1GPR, eax.gpr());
3598         m_jit.assembler().cdq();
3599         m_jit.assembler().idivl_r(op2GPR);
3600
3601         if (op2TempGPR != InvalidGPRReg)
3602             unlock(op2TempGPR);
3603
3604         // Check that we're not about to create negative zero.
3605         if (shouldCheckNegativeZero(node->arithMode())) {
3606             JITCompiler::Jump numeratorPositive = m_jit.branch32(JITCompiler::GreaterThanOrEqual, op1SaveGPR, TrustedImm32(0));
3607             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::Zero, edx.gpr()));
3608             numeratorPositive.link(&m_jit);
3609         }
3610
3611         if (op1SaveGPR != op1GPR)
3612             unlock(op1SaveGPR);
3613
3614         done.link(&m_jit);
3615         int32Result(edx.gpr(), node);
3616
3617 #elif HAVE(ARM_IDIV_INSTRUCTIONS) || CPU(ARM64)
3618         GPRTemporary temp(this);
3619         GPRTemporary quotientThenRemainder(this);
3620         GPRTemporary multiplyAnswer(this);
3621         GPRReg dividendGPR = op1.gpr();
3622         GPRReg divisorGPR = op2.gpr();
3623         GPRReg quotientThenRemainderGPR = quotientThenRemainder.gpr();
3624         GPRReg multiplyAnswerGPR = multiplyAnswer.gpr();
3625
3626         JITCompiler::JumpList done;
3627
3628         if (shouldCheckOverflow(node->arithMode()))
3629             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::Zero, divisorGPR));
3630         else {
3631             JITCompiler::Jump denominatorNotZero = m_jit.branchTest32(JITCompiler::NonZero, divisorGPR);
3632             m_jit.move(divisorGPR, quotientThenRemainderGPR);
3633             done.append(m_jit.jump());
3634             denominatorNotZero.link(&m_jit);
3635         }
3636
3637         m_jit.assembler().sdiv<32>(quotientThenRemainderGPR, dividendGPR, divisorGPR);
3638         // FIXME: It seems like there are cases where we don't need this? What if we have
3639         // arithMode() == Arith::Unchecked?
3640         // https://bugs.webkit.org/show_bug.cgi?id=126444
3641         speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchMul32(JITCompiler::Overflow, quotientThenRemainderGPR, divisorGPR, multiplyAnswerGPR));
3642 #if HAVE(ARM_IDIV_INSTRUCTIONS)
3643         m_jit.assembler().sub(quotientThenRemainderGPR, dividendGPR, multiplyAnswerGPR);
3644 #else
3645         m_jit.assembler().sub<32>(quotientThenRemainderGPR, dividendGPR, multiplyAnswerGPR);
3646 #endif
3647
3648         // If the user cares about negative zero, then speculate that we're not about
3649         // to produce negative zero.
3650         if (shouldCheckNegativeZero(node->arithMode())) {
3651             // Check that we're not about to create negative zero.
3652             JITCompiler::Jump numeratorPositive = m_jit.branch32(JITCompiler::GreaterThanOrEqual, dividendGPR, TrustedImm32(0));
3653             speculationCheck(Overflow, JSValueRegs(), 0, m_jit.branchTest32(JITCompiler::Zero, quotientThenRemainderGPR));
3654             numeratorPositive.link(&m_jit);
3655         }
3656
3657         done.link(&m_jit);
3658
3659         int32Result(quotientThenRemainderGPR, node);
3660 #else // not architecture that can do integer division
3661         RELEASE_ASSERT_NOT_REACHED();
3662 #endif
3663         return;
3664     }
3665
3666     case DoubleRepUse: {
3667         SpeculateDoubleOperand op1(this, node->child1());
3668         SpeculateDoubleOperand op2(this, node->child2());
3669
3670         FPRReg op1FPR = op1.fpr();
3671         FPRReg op2FPR = op2.fpr();
3672
3673         flushRegisters();
3674
3675         FPRResult result(this);
3676
3677         callOperation(fmodAsDFGOperation, result.fpr(), op1FPR, op2FPR);
3678
3679         doubleResult(result.fpr(), node);
3680         return;
3681     }
3682
3683     default:
3684         RELEASE_ASSERT_NOT_REACHED();
3685         return;
3686     }
3687 }
3688
3689 void SpeculativeJIT::compileArithRound(Node* node)
3690 {
3691     ASSERT(node->child1().useKind() == DoubleRepUse);
3692
3693     SpeculateDoubleOperand value(this, node->child1());
3694     FPRReg valueFPR = value.fpr();
3695
3696     if (producesInteger(node->arithRoundingMode()) && !shouldCheckNegativeZero(node->arithRoundingMode())) {
3697         FPRTemporary oneHalf(this);
3698         GPRTemporary roundedResultAsInt32(this);
3699         FPRReg oneHalfFPR = oneHalf.fpr();
3700         GPRReg resultGPR = roundedResultAsInt32.gpr();
3701
3702         static const double halfConstant = 0.5;
3703         m_jit.loadDouble(MacroAssembler::TrustedImmPtr(&halfConstant), oneHalfFPR);
3704         m_jit.addDouble(valueFPR, oneHalfFPR);
3705
3706         JITCompiler::Jump truncationFailed = m_jit.branchTruncateDoubleToInt32(oneHalfFPR, resultGPR);
3707         speculationCheck(Overflow, JSValueRegs(), node, truncationFailed);
3708         int32Result(resultGPR, node);
3709         return;
3710     }
3711
3712     flushRegisters();
3713     FPRResult roundedResultAsDouble(this);
3714     FPRReg resultFPR = roundedResultAsDouble.fpr();
3715     callOperation(jsRound, resultFPR, valueFPR);
3716     m_jit.exceptionCheck();
3717     if (producesInteger(node->arithRoundingMode())) {
3718         GPRTemporary roundedResultAsInt32(this);
3719         FPRTemporary scratch(this);
3720         FPRReg scratchFPR = scratch.fpr();
3721         GPRReg resultGPR = roundedResultAsInt32.gpr();
3722         JITCompiler::JumpList failureCases;
3723         m_jit.branchConvertDoubleToInt32(resultFPR, resultGPR, failureCases, scratchFPR);
3724         speculationCheck(Overflow, JSValueRegs(), node, failureCases);
3725
3726         int32Result(resultGPR, node);
3727     } else
3728         doubleResult(resultFPR, node);
3729 }
3730
3731 void SpeculativeJIT::compileArithSqrt(Node* node)
3732 {
3733     SpeculateDoubleOperand op1(this, node->child1());
3734     FPRReg op1FPR = op1.fpr();
3735
3736     if (!MacroAssembler::supportsFloatingPointSqrt() || !Options::enableArchitectureSpecificOptimizations()) {
3737         flushRegisters();
3738         FPRResult result(this);
3739         callOperation(sqrt, result.fpr(), op1FPR);
3740         doubleResult(result.fpr(), node);
3741     } else {
3742         FPRTemporary result(this, op1);
3743         m_jit.sqrtDouble(op1.fpr(), result.fpr());
3744         doubleResult(result.fpr(), node);
3745     }
3746 }
3747
3748 // For small positive integers , it is worth doing a tiny inline loop to exponentiate the base.
3749 // Every register is clobbered by this helper.
3750 static MacroAssembler::Jump compileArithPowIntegerFastPath(JITCompiler& assembler, FPRReg xOperand, GPRReg yOperand, FPRReg result)
3751 {
3752     MacroAssembler::JumpList skipFastPath;
3753     skipFastPath.append(assembler.branch32(MacroAssembler::LessThan, yOperand, MacroAssembler::TrustedImm32(0)));
3754     skipFastPath.append(assembler.branch32(MacroAssembler::GreaterThan, yOperand, MacroAssembler::TrustedImm32(1000)));
3755
3756     static const double oneConstant = 1.0;
3757     assembler.loadDouble(MacroAssembler::TrustedImmPtr(&oneConstant), result);
3758
3759     MacroAssembler::Label startLoop(assembler.label());
3760     MacroAssembler::Jump exponentIsEven = assembler.branchTest32(MacroAssembler::Zero, yOperand, MacroAssembler::TrustedImm32(1));
3761     assembler.mulDouble(xOperand, result);
3762     exponentIsEven.link(&assembler);
3763     assembler.mulDouble(xOperand, xOperand);
3764     assembler.rshift32(MacroAssembler::TrustedImm32(1), yOperand);
3765     assembler.branchTest32(MacroAssembler::NonZero, yOperand).linkTo(startLoop, &assembler);
3766
3767     MacroAssembler::Jump skipSlowPath = assembler.jump();
3768     skipFastPath.link(&assembler);
3769
3770     return skipSlowPath;
3771 }
3772
3773 void SpeculativeJIT::compileArithPow(Node* node)
3774 {
3775     if (node->child2().useKind() == Int32Use) {
3776         SpeculateDoubleOperand xOperand(this, node->child1());
3777         SpeculateInt32Operand yOperand(this, node->child2());
3778         FPRReg xOperandfpr = xOperand.fpr();
3779         GPRReg yOperandGpr = yOperand.gpr();
3780         FPRTemporary yOperandfpr(this);
3781
3782         flushRegisters();
3783
3784         FPRResult result(this);
3785         FPRReg resultFpr = result.fpr();
3786
3787         FPRTemporary xOperandCopy(this);
3788         FPRReg xOperandCopyFpr = xOperandCopy.fpr();
3789         m_jit.moveDouble(xOperandfpr, xOperandCopyFpr);
3790
3791         GPRTemporary counter(this);
3792         GPRReg counterGpr = counter.gpr();
3793         m_jit.move(yOperandGpr, counterGpr);
3794
3795         MacroAssembler::Jump skipFallback = compileArithPowIntegerFastPath(m_jit, xOperandCopyFpr, coun