void JITCompiler::disassemble(LinkBuffer& linkBuffer)
{
if (shouldShowDisassembly())
m_disassembler->dump(linkBuffer);
if (m_graph.m_plan.compilation)
m_disassembler->reportToProfiler(m_graph.m_plan.compilation.get(), linkBuffer);
}
JITCompiler::JITCompiler(Graph& dfg)
: CCallHelpers(&dfg.m_vm, dfg.m_codeBlock)
, m_graph(dfg)
, m_jitCode(adoptRef(new JITCode()))
, m_blockHeads(dfg.numBlocks())
{
if (shouldShowDisassembly() || m_graph.m_vm.m_perBytecodeProfiler)
m_disassembler = adoptPtr(new Disassembler(dfg));
}
bool JITCompiler::compile(JITCode& entry)
{
SamplingRegion samplingRegion("DFG Backend");
setStartOfCode();
compileEntry();
SpeculativeJIT speculative(*this);
compileBody(speculative);
setEndOfMainPath();
// Generate slow path code.
speculative.runSlowPathGenerators();
compileExceptionHandlers();
linkOSRExits();
// Create OSR entry trampolines if necessary.
speculative.createOSREntries();
setEndOfCode();
LinkBuffer linkBuffer(*m_vm, this, m_codeBlock, JITCompilationCanFail);
if (linkBuffer.didFailToAllocate())
return false;
link(linkBuffer);
speculative.linkOSREntries(linkBuffer);
if (shouldShowDisassembly())
m_disassembler->dump(linkBuffer);
if (m_graph.m_compilation)
m_disassembler->reportToProfiler(m_graph.m_compilation.get(), linkBuffer);
entry = JITCode(
linkBuffer.finalizeCodeWithoutDisassembly(),
JITCode::DFGJIT);
return true;
}
void compile(State& state, Safepoint::Result& safepointResult)
{
char* error = 0;
{
GraphSafepoint safepoint(state.graph, safepointResult);
LLVMMCJITCompilerOptions options;
llvm->InitializeMCJITCompilerOptions(&options, sizeof(options));
options.OptLevel = Options::llvmBackendOptimizationLevel();
options.NoFramePointerElim = true;
if (Options::useLLVMSmallCodeModel())
options.CodeModel = LLVMCodeModelSmall;
options.EnableFastISel = Options::enableLLVMFastISel();
options.MCJMM = llvm->CreateSimpleMCJITMemoryManager(
&state, mmAllocateCodeSection, mmAllocateDataSection, mmApplyPermissions, mmDestroy);
LLVMExecutionEngineRef engine;
if (isARM64())
#if OS(DARWIN)
llvm->SetTarget(state.module, "arm64-apple-ios");
#elif OS(LINUX)
llvm->SetTarget(state.module, "aarch64-linux-gnu");
#else
#error "Unrecognized OS"
#endif
if (llvm->CreateMCJITCompilerForModule(&engine, state.module, &options, sizeof(options), &error)) {
dataLog("FATAL: Could not create LLVM execution engine: ", error, "\n");
CRASH();
}
// The data layout also has to be set in the module. Get the data layout from the MCJIT and apply
// it to the module.
LLVMTargetMachineRef targetMachine = llvm->GetExecutionEngineTargetMachine(engine);
LLVMTargetDataRef targetData = llvm->GetExecutionEngineTargetData(engine);
char* stringRepOfTargetData = llvm->CopyStringRepOfTargetData(targetData);
llvm->SetDataLayout(state.module, stringRepOfTargetData);
free(stringRepOfTargetData);
LLVMPassManagerRef functionPasses = 0;
LLVMPassManagerRef modulePasses;
if (Options::llvmSimpleOpt()) {
modulePasses = llvm->CreatePassManager();
llvm->AddTargetData(targetData, modulePasses);
llvm->AddAnalysisPasses(targetMachine, modulePasses);
llvm->AddPromoteMemoryToRegisterPass(modulePasses);
llvm->AddGlobalOptimizerPass(modulePasses);
llvm->AddFunctionInliningPass(modulePasses);
llvm->AddPruneEHPass(modulePasses);
llvm->AddGlobalDCEPass(modulePasses);
llvm->AddConstantPropagationPass(modulePasses);
llvm->AddAggressiveDCEPass(modulePasses);
llvm->AddInstructionCombiningPass(modulePasses);
// BEGIN - DO NOT CHANGE THE ORDER OF THE ALIAS ANALYSIS PASSES
llvm->AddTypeBasedAliasAnalysisPass(modulePasses);
llvm->AddBasicAliasAnalysisPass(modulePasses);
// END - DO NOT CHANGE THE ORDER OF THE ALIAS ANALYSIS PASSES
llvm->AddGVNPass(modulePasses);
llvm->AddCFGSimplificationPass(modulePasses);
llvm->AddDeadStoreEliminationPass(modulePasses);
llvm->RunPassManager(modulePasses, state.module);
} else {
LLVMPassManagerBuilderRef passBuilder = llvm->PassManagerBuilderCreate();
llvm->PassManagerBuilderSetOptLevel(passBuilder, Options::llvmOptimizationLevel());
llvm->PassManagerBuilderUseInlinerWithThreshold(passBuilder, 275);
llvm->PassManagerBuilderSetSizeLevel(passBuilder, Options::llvmSizeLevel());
functionPasses = llvm->CreateFunctionPassManagerForModule(state.module);
modulePasses = llvm->CreatePassManager();
llvm->AddTargetData(llvm->GetExecutionEngineTargetData(engine), modulePasses);
llvm->PassManagerBuilderPopulateFunctionPassManager(passBuilder, functionPasses);
llvm->PassManagerBuilderPopulateModulePassManager(passBuilder, modulePasses);
llvm->PassManagerBuilderDispose(passBuilder);
llvm->InitializeFunctionPassManager(functionPasses);
for (LValue function = llvm->GetFirstFunction(state.module); function; function = llvm->GetNextFunction(function))
llvm->RunFunctionPassManager(functionPasses, function);
llvm->FinalizeFunctionPassManager(functionPasses);
llvm->RunPassManager(modulePasses, state.module);
}
if (shouldShowDisassembly() || verboseCompilationEnabled())
state.dumpState("after optimization");
// FIXME: Need to add support for the case where JIT memory allocation failed.
// https://bugs.webkit.org/show_bug.cgi?id=113620
state.generatedFunction = reinterpret_cast<GeneratedFunction>(llvm->GetPointerToGlobal(engine, state.function));
if (functionPasses)
llvm->DisposePassManager(functionPasses);
llvm->DisposePassManager(modulePasses);
llvm->DisposeExecutionEngine(engine);
}
if (safepointResult.didGetCancelled())
return;
RELEASE_ASSERT(!state.graph.m_vm.heap.isCollecting());
if (shouldShowDisassembly()) {
for (unsigned i = 0; i < state.jitCode->handles().size(); ++i) {
ExecutableMemoryHandle* handle = state.jitCode->handles()[i].get();
dataLog(
"Generated LLVM code for ",
CodeBlockWithJITType(state.graph.m_codeBlock, JITCode::FTLJIT),
" #", i, ", ", state.codeSectionNames[i], ":\n");
disassemble(
MacroAssemblerCodePtr(handle->start()), handle->sizeInBytes(),
" ", WTF::dataFile(), LLVMSubset);
}
for (unsigned i = 0; i < state.jitCode->dataSections().size(); ++i) {
DataSection* section = state.jitCode->dataSections()[i].get();
dataLog(
"Generated LLVM data section for ",
CodeBlockWithJITType(state.graph.m_codeBlock, JITCode::FTLJIT),
" #", i, ", ", state.dataSectionNames[i], ":\n");
dumpDataSection(section, " ");
}
}
bool didSeeUnwindInfo = state.jitCode->unwindInfo.parse(
state.unwindDataSection, state.unwindDataSectionSize,
state.generatedFunction);
if (shouldShowDisassembly()) {
dataLog("Unwind info for ", CodeBlockWithJITType(state.graph.m_codeBlock, JITCode::FTLJIT), ":\n");
if (didSeeUnwindInfo)
dataLog(" ", state.jitCode->unwindInfo, "\n");
else
dataLog(" <no unwind info>\n");
}
if (state.stackmapsSection && state.stackmapsSection->size()) {
if (shouldShowDisassembly()) {
dataLog(
"Generated LLVM stackmaps section for ",
CodeBlockWithJITType(state.graph.m_codeBlock, JITCode::FTLJIT), ":\n");
dataLog(" Raw data:\n");
dumpDataSection(state.stackmapsSection.get(), " ");
}
RefPtr<DataView> stackmapsData = DataView::create(
ArrayBuffer::create(state.stackmapsSection->base(), state.stackmapsSection->size()));
state.jitCode->stackmaps.parse(stackmapsData.get());
if (shouldShowDisassembly()) {
dataLog(" Structured data:\n");
state.jitCode->stackmaps.dumpMultiline(WTF::dataFile(), " ");
}
StackMaps::RecordMap recordMap = state.jitCode->stackmaps.computeRecordMap();
fixFunctionBasedOnStackMaps(
state, state.graph.m_codeBlock, state.jitCode.get(), state.generatedFunction,
recordMap, didSeeUnwindInfo);
if (shouldShowDisassembly()) {
for (unsigned i = 0; i < state.jitCode->handles().size(); ++i) {
if (state.codeSectionNames[i] != SECTION_NAME("text"))
continue;
ExecutableMemoryHandle* handle = state.jitCode->handles()[i].get();
dataLog(
"Generated LLVM code after stackmap-based fix-up for ",
CodeBlockWithJITType(state.graph.m_codeBlock, JITCode::FTLJIT),
" in ", state.graph.m_plan.mode, " #", i, ", ",
state.codeSectionNames[i], ":\n");
disassemble(
MacroAssemblerCodePtr(handle->start()), handle->sizeInBytes(),
" ", WTF::dataFile(), LLVMSubset);
}
}
}
state.module = 0; // We no longer own the module.
}
void compileOSRExit(ExecState* exec)
{
SamplingRegion samplingRegion("DFG OSR Exit Compilation");
CodeBlock* codeBlock = exec->codeBlock();
ASSERT(codeBlock);
ASSERT(codeBlock->getJITType() == JITCode::DFGJIT);
JSGlobalData* globalData = &exec->globalData();
uint32_t exitIndex = globalData->osrExitIndex;
OSRExit& exit = codeBlock->osrExit(exitIndex);
// Make sure all code on our inline stack is JIT compiled. This is necessary since
// we may opt to inline a code block even before it had ever been compiled by the
// JIT, but our OSR exit infrastructure currently only works if the target of the
// OSR exit is JIT code. This could be changed since there is nothing particularly
// hard about doing an OSR exit into the interpreter, but for now this seems to make
// sense in that if we're OSR exiting from inlined code of a DFG code block, then
// probably it's a good sign that the thing we're exiting into is hot. Even more
// interestingly, since the code was inlined, it may never otherwise get JIT
// compiled since the act of inlining it may ensure that it otherwise never runs.
for (CodeOrigin codeOrigin = exit.m_codeOrigin; codeOrigin.inlineCallFrame; codeOrigin = codeOrigin.inlineCallFrame->caller) {
static_cast<FunctionExecutable*>(codeOrigin.inlineCallFrame->executable.get())
->baselineCodeBlockFor(codeOrigin.inlineCallFrame->isCall ? CodeForCall : CodeForConstruct)
->jitCompile(exec);
}
// Compute the value recoveries.
Operands<ValueRecovery> operands;
codeBlock->variableEventStream().reconstruct(codeBlock, exit.m_codeOrigin, codeBlock->minifiedDFG(), exit.m_streamIndex, operands);
// There may be an override, for forward speculations.
if (!!exit.m_valueRecoveryOverride) {
operands.setOperand(
exit.m_valueRecoveryOverride->operand, exit.m_valueRecoveryOverride->recovery);
}
SpeculationRecovery* recovery = 0;
if (exit.m_recoveryIndex)
recovery = &codeBlock->speculationRecovery(exit.m_recoveryIndex - 1);
#if DFG_ENABLE(DEBUG_VERBOSE)
dataLog(
"Generating OSR exit #", exitIndex, " (seq#", exit.m_streamIndex,
", bc#", exit.m_codeOrigin.bytecodeIndex, ", @", exit.m_nodeIndex, ", ",
exit.m_kind, ") for ", *codeBlock, ".\n");
#endif
{
CCallHelpers jit(globalData, codeBlock);
OSRExitCompiler exitCompiler(jit);
jit.jitAssertHasValidCallFrame();
if (globalData->m_perBytecodeProfiler && codeBlock->compilation()) {
Profiler::Database& database = *globalData->m_perBytecodeProfiler;
Profiler::Compilation* compilation = codeBlock->compilation();
Profiler::OSRExit* profilerExit = compilation->addOSRExit(
exitIndex, Profiler::OriginStack(database, codeBlock, exit.m_codeOrigin),
exit.m_kind,
exit.m_watchpointIndex != std::numeric_limits<unsigned>::max());
jit.add64(CCallHelpers::TrustedImm32(1), CCallHelpers::AbsoluteAddress(profilerExit->counterAddress()));
}
exitCompiler.compileExit(exit, operands, recovery);
LinkBuffer patchBuffer(*globalData, &jit, codeBlock);
exit.m_code = FINALIZE_CODE_IF(
shouldShowDisassembly(),
patchBuffer,
("DFG OSR exit #%u (bc#%u, @%u, %s) from %s",
exitIndex, exit.m_codeOrigin.bytecodeIndex, exit.m_nodeIndex,
exitKindToString(exit.m_kind), toCString(*codeBlock).data()));
}
{
RepatchBuffer repatchBuffer(codeBlock);
repatchBuffer.relink(exit.codeLocationForRepatch(codeBlock), CodeLocationLabel(exit.m_code.code()));
}
globalData->osrExitJumpDestination = exit.m_code.code().executableAddress();
}
void compileOSRExit(ExecState* exec)
{
SamplingRegion samplingRegion("DFG OSR Exit Compilation");
CodeBlock* codeBlock = exec->codeBlock();
ASSERT(codeBlock);
ASSERT(codeBlock->jitType() == JITCode::DFGJIT);
VM* vm = &exec->vm();
// It's sort of preferable that we don't GC while in here. Anyways, doing so wouldn't
// really be profitable.
DeferGCForAWhile deferGC(vm->heap);
uint32_t exitIndex = vm->osrExitIndex;
OSRExit& exit = codeBlock->jitCode()->dfg()->osrExit[exitIndex];
prepareCodeOriginForOSRExit(exec, exit.m_codeOrigin);
// Compute the value recoveries.
Operands<ValueRecovery> operands;
codeBlock->jitCode()->dfg()->variableEventStream.reconstruct(codeBlock, exit.m_codeOrigin, codeBlock->jitCode()->dfg()->minifiedDFG, exit.m_streamIndex, operands);
// There may be an override, for forward speculations.
if (!!exit.m_valueRecoveryOverride) {
operands.setOperand(
exit.m_valueRecoveryOverride->operand, exit.m_valueRecoveryOverride->recovery);
}
SpeculationRecovery* recovery = 0;
if (exit.m_recoveryIndex != UINT_MAX)
recovery = &codeBlock->jitCode()->dfg()->speculationRecovery[exit.m_recoveryIndex];
{
CCallHelpers jit(vm, codeBlock);
OSRExitCompiler exitCompiler(jit);
jit.jitAssertHasValidCallFrame();
if (vm->m_perBytecodeProfiler && codeBlock->jitCode()->dfgCommon()->compilation) {
Profiler::Database& database = *vm->m_perBytecodeProfiler;
Profiler::Compilation* compilation = codeBlock->jitCode()->dfgCommon()->compilation.get();
Profiler::OSRExit* profilerExit = compilation->addOSRExit(
exitIndex, Profiler::OriginStack(database, codeBlock, exit.m_codeOrigin),
exit.m_kind, exit.m_kind == UncountableInvalidation);
jit.add64(CCallHelpers::TrustedImm32(1), CCallHelpers::AbsoluteAddress(profilerExit->counterAddress()));
}
exitCompiler.compileExit(exit, operands, recovery);
LinkBuffer patchBuffer(*vm, jit, codeBlock);
exit.m_code = FINALIZE_CODE_IF(
shouldShowDisassembly() || Options::verboseOSR(),
patchBuffer,
("DFG OSR exit #%u (%s, %s) from %s, with operands = %s",
exitIndex, toCString(exit.m_codeOrigin).data(),
exitKindToString(exit.m_kind), toCString(*codeBlock).data(),
toCString(ignoringContext<DumpContext>(operands)).data()));
}
{
RepatchBuffer repatchBuffer(codeBlock);
repatchBuffer.relink(exit.codeLocationForRepatch(codeBlock), CodeLocationLabel(exit.m_code.code()));
}
vm->osrExitJumpDestination = exit.m_code.code().executableAddress();
}
bool JITCompiler::compileFunction(JITCode& entry, MacroAssemblerCodePtr& entryWithArityCheck)
{
SamplingRegion samplingRegion("DFG Backend");
setStartOfCode();
compileEntry();
// === Function header code generation ===
// This is the main entry point, without performing an arity check.
// If we needed to perform an arity check we will already have moved the return address,
// so enter after this.
Label fromArityCheck(this);
// Plant a check that sufficient space is available in the JSStack.
// FIXME: https://bugs.webkit.org/show_bug.cgi?id=56291
addPtr(TrustedImm32(m_codeBlock->m_numCalleeRegisters * sizeof(Register)), GPRInfo::callFrameRegister, GPRInfo::regT1);
Jump stackCheck = branchPtr(Below, AbsoluteAddress(m_vm->interpreter->stack().addressOfEnd()), GPRInfo::regT1);
// Return here after stack check.
Label fromStackCheck = label();
// === Function body code generation ===
SpeculativeJIT speculative(*this);
compileBody(speculative);
setEndOfMainPath();
// === Function footer code generation ===
//
// Generate code to perform the slow stack check (if the fast one in
// the function header fails), and generate the entry point with arity check.
//
// Generate the stack check; if the fast check in the function head fails,
// we need to call out to a helper function to check whether more space is available.
// FIXME: change this from a cti call to a DFG style operation (normal C calling conventions).
stackCheck.link(this);
move(stackPointerRegister, GPRInfo::argumentGPR0);
poke(GPRInfo::callFrameRegister, OBJECT_OFFSETOF(struct JITStackFrame, callFrame) / sizeof(void*));
CallBeginToken token;
beginCall(CodeOrigin(0), token);
Call callStackCheck = call();
notifyCall(callStackCheck, CodeOrigin(0), token);
jump(fromStackCheck);
// The fast entry point into a function does not check the correct number of arguments
// have been passed to the call (we only use the fast entry point where we can statically
// determine the correct number of arguments have been passed, or have already checked).
// In cases where an arity check is necessary, we enter here.
// FIXME: change this from a cti call to a DFG style operation (normal C calling conventions).
Label arityCheck = label();
compileEntry();
load32(AssemblyHelpers::payloadFor((VirtualRegister)JSStack::ArgumentCount), GPRInfo::regT1);
branch32(AboveOrEqual, GPRInfo::regT1, TrustedImm32(m_codeBlock->numParameters())).linkTo(fromArityCheck, this);
move(stackPointerRegister, GPRInfo::argumentGPR0);
poke(GPRInfo::callFrameRegister, OBJECT_OFFSETOF(struct JITStackFrame, callFrame) / sizeof(void*));
beginCall(CodeOrigin(0), token);
Call callArityCheck = call();
notifyCall(callArityCheck, CodeOrigin(0), token);
move(GPRInfo::regT0, GPRInfo::callFrameRegister);
jump(fromArityCheck);
// Generate slow path code.
speculative.runSlowPathGenerators();
compileExceptionHandlers();
linkOSRExits();
// Create OSR entry trampolines if necessary.
speculative.createOSREntries();
setEndOfCode();
// === Link ===
LinkBuffer linkBuffer(*m_vm, this, m_codeBlock, JITCompilationCanFail);
if (linkBuffer.didFailToAllocate())
return false;
link(linkBuffer);
speculative.linkOSREntries(linkBuffer);
// FIXME: switch the stack check & arity check over to DFGOpertaion style calls, not JIT stubs.
linkBuffer.link(callStackCheck, cti_stack_check);
linkBuffer.link(callArityCheck, m_codeBlock->m_isConstructor ? cti_op_construct_arityCheck : cti_op_call_arityCheck);
if (shouldShowDisassembly())
m_disassembler->dump(linkBuffer);
if (m_graph.m_compilation)
m_disassembler->reportToProfiler(m_graph.m_compilation.get(), linkBuffer);
entryWithArityCheck = linkBuffer.locationOf(arityCheck);
entry = JITCode(
linkBuffer.finalizeCodeWithoutDisassembly(),
JITCode::DFGJIT);
return true;
}
Plan::CompilationPath Plan::compileInThreadImpl(LongLivedState& longLivedState)
{
if (verboseCompilationEnabled(mode) && osrEntryBytecodeIndex != UINT_MAX) {
dataLog("\n");
dataLog("Compiler must handle OSR entry from bc#", osrEntryBytecodeIndex, " with values: ", mustHandleValues, "\n");
dataLog("\n");
}
Graph dfg(vm, *this, longLivedState);
if (!parse(dfg)) {
finalizer = std::make_unique<FailedFinalizer>(*this);
return FailPath;
}
codeBlock->setCalleeSaveRegisters(RegisterSet::dfgCalleeSaveRegisters());
// By this point the DFG bytecode parser will have potentially mutated various tables
// in the CodeBlock. This is a good time to perform an early shrink, which is more
// powerful than a late one. It's safe to do so because we haven't generated any code
// that references any of the tables directly, yet.
codeBlock->shrinkToFit(CodeBlock::EarlyShrink);
if (validationEnabled())
validate(dfg);
if (Options::dumpGraphAfterParsing()) {
dataLog("Graph after parsing:\n");
dfg.dump();
}
performLiveCatchVariablePreservationPhase(dfg);
if (Options::enableMaximalFlushInsertionPhase())
performMaximalFlushInsertion(dfg);
performCPSRethreading(dfg);
performUnification(dfg);
performPredictionInjection(dfg);
performStaticExecutionCountEstimation(dfg);
if (mode == FTLForOSREntryMode) {
bool result = performOSREntrypointCreation(dfg);
if (!result) {
finalizer = std::make_unique<FailedFinalizer>(*this);
return FailPath;
}
performCPSRethreading(dfg);
}
if (validationEnabled())
validate(dfg);
performBackwardsPropagation(dfg);
performPredictionPropagation(dfg);
performFixup(dfg);
performStructureRegistration(dfg);
performInvalidationPointInjection(dfg);
performTypeCheckHoisting(dfg);
dfg.m_fixpointState = FixpointNotConverged;
// For now we're back to avoiding a fixpoint. Note that we've ping-ponged on this decision
// many times. For maximum throughput, it's best to fixpoint. But the throughput benefit is
// small and not likely to show up in FTL anyway. On the other hand, not fixpointing means
// that the compiler compiles more quickly. We want the third tier to compile quickly, which
// not fixpointing accomplishes; and the fourth tier shouldn't need a fixpoint.
if (validationEnabled())
validate(dfg);
performStrengthReduction(dfg);
performLocalCSE(dfg);
performCPSRethreading(dfg);
performCFA(dfg);
performConstantFolding(dfg);
bool changed = false;
changed |= performCFGSimplification(dfg);
changed |= performLocalCSE(dfg);
if (validationEnabled())
validate(dfg);
performCPSRethreading(dfg);
if (!isFTL(mode)) {
// Only run this if we're not FTLing, because currently for a LoadVarargs that is forwardable and
// in a non-varargs inlined call frame, this will generate ForwardVarargs while the FTL
// ArgumentsEliminationPhase will create a sequence of GetStack+PutStacks. The GetStack+PutStack
// sequence then gets sunk, eliminating anything that looks like an escape for subsequent phases,
// while the ForwardVarargs doesn't get simplified until later (or not at all) and looks like an
// escape for all of the arguments. This then disables object allocation sinking.
//
// So, for now, we just disable this phase for the FTL.
//
// If we wanted to enable it, we'd have to do any of the following:
// - Enable ForwardVarargs->GetStack+PutStack strength reduction, and have that run before
// PutStack sinking and object allocation sinking.
// - Make VarargsForwarding emit a GetLocal+SetLocal sequence, that we can later turn into
// GetStack+PutStack.
//
// But, it's not super valuable to enable those optimizations, since the FTL
// ArgumentsEliminationPhase does everything that this phase does, and it doesn't introduce this
// pathology.
changed |= performVarargsForwarding(dfg); // Do this after CFG simplification and CPS rethreading.
}
if (changed) {
performCFA(dfg);
performConstantFolding(dfg);
}
// If we're doing validation, then run some analyses, to give them an opportunity
// to self-validate. Now is as good a time as any to do this.
if (validationEnabled()) {
dfg.m_dominators.computeIfNecessary(dfg);
dfg.m_naturalLoops.computeIfNecessary(dfg);
dfg.m_prePostNumbering.computeIfNecessary(dfg);
}
switch (mode) {
case DFGMode: {
dfg.m_fixpointState = FixpointConverged;
performTierUpCheckInjection(dfg);
performFastStoreBarrierInsertion(dfg);
performCleanUp(dfg);
performCPSRethreading(dfg);
performDCE(dfg);
performPhantomInsertion(dfg);
performStackLayout(dfg);
performVirtualRegisterAllocation(dfg);
performWatchpointCollection(dfg);
dumpAndVerifyGraph(dfg, "Graph after optimization:");
JITCompiler dataFlowJIT(dfg);
if (codeBlock->codeType() == FunctionCode)
dataFlowJIT.compileFunction();
else
dataFlowJIT.compile();
return DFGPath;
}
case FTLMode:
case FTLForOSREntryMode: {
#if ENABLE(FTL_JIT)
if (FTL::canCompile(dfg) == FTL::CannotCompile) {
finalizer = std::make_unique<FailedFinalizer>(*this);
return FailPath;
}
performCleanUp(dfg); // Reduce the graph size a bit.
performCriticalEdgeBreaking(dfg);
if (Options::createPreHeaders())
performLoopPreHeaderCreation(dfg);
performCPSRethreading(dfg);
performSSAConversion(dfg);
performSSALowering(dfg);
// Ideally, these would be run to fixpoint with the object allocation sinking phase.
performArgumentsElimination(dfg);
performPutStackSinking(dfg);
performConstantHoisting(dfg);
performGlobalCSE(dfg);
performLivenessAnalysis(dfg);
performIntegerRangeOptimization(dfg);
performLivenessAnalysis(dfg);
performCFA(dfg);
performConstantFolding(dfg);
performCleanUp(dfg); // Reduce the graph size a lot.
changed = false;
changed |= performStrengthReduction(dfg);
if (Options::enableObjectAllocationSinking()) {
changed |= performCriticalEdgeBreaking(dfg);
changed |= performObjectAllocationSinking(dfg);
}
if (changed) {
// State-at-tail and state-at-head will be invalid if we did strength reduction since
// it might increase live ranges.
performLivenessAnalysis(dfg);
performCFA(dfg);
performConstantFolding(dfg);
}
// Currently, this relies on pre-headers still being valid. That precludes running CFG
// simplification before it, unless we re-created the pre-headers. There wouldn't be anything
// wrong with running LICM earlier, if we wanted to put other CFG transforms above this point.
// Alternatively, we could run loop pre-header creation after SSA conversion - but if we did that
// then we'd need to do some simple SSA fix-up.
performLICM(dfg);
performCleanUp(dfg);
performIntegerCheckCombining(dfg);
performGlobalCSE(dfg);
// At this point we're not allowed to do any further code motion because our reasoning
// about code motion assumes that it's OK to insert GC points in random places.
dfg.m_fixpointState = FixpointConverged;
performLivenessAnalysis(dfg);
performCFA(dfg);
performGlobalStoreBarrierInsertion(dfg);
if (Options::enableMovHintRemoval())
performMovHintRemoval(dfg);
performCleanUp(dfg);
performDCE(dfg); // We rely on this to kill dead code that won't be recognized as dead by LLVM.
performStackLayout(dfg);
performLivenessAnalysis(dfg);
performOSRAvailabilityAnalysis(dfg);
performWatchpointCollection(dfg);
if (FTL::canCompile(dfg) == FTL::CannotCompile) {
finalizer = std::make_unique<FailedFinalizer>(*this);
return FailPath;
}
dumpAndVerifyGraph(dfg, "Graph just before FTL lowering:", shouldShowDisassembly(mode));
bool haveLLVM;
Safepoint::Result safepointResult;
{
GraphSafepoint safepoint(dfg, safepointResult);
haveLLVM = initializeLLVM();
}
if (safepointResult.didGetCancelled())
return CancelPath;
if (!haveLLVM) {
if (Options::ftlCrashesIfCantInitializeLLVM()) {
dataLog("LLVM can't be initialized.\n");
CRASH();
}
finalizer = std::make_unique<FailedFinalizer>(*this);
return FailPath;
}
FTL::State state(dfg);
FTL::lowerDFGToLLVM(state);
if (computeCompileTimes())
m_timeBeforeFTL = monotonicallyIncreasingTimeMS();
if (Options::llvmAlwaysFailsBeforeCompile()) {
FTL::fail(state);
return FTLPath;
}
FTL::compile(state, safepointResult);
if (safepointResult.didGetCancelled())
return CancelPath;
if (Options::llvmAlwaysFailsBeforeLink()) {
FTL::fail(state);
return FTLPath;
}
if (state.allocationFailed) {
FTL::fail(state);
return FTLPath;
}
if (state.jitCode->stackmaps.stackSize() > Options::llvmMaxStackSize()) {
FTL::fail(state);
return FTLPath;
}
FTL::link(state);
if (state.allocationFailed) {
FTL::fail(state);
return FTLPath;
}
return FTLPath;
#else
RELEASE_ASSERT_NOT_REACHED();
return FailPath;
#endif // ENABLE(FTL_JIT)
}
default:
RELEASE_ASSERT_NOT_REACHED();
return FailPath;
}
}
