| /* |
| * Copyright (C) 2011-2019 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "DFGJITCompiler.h" |
| |
| #if ENABLE(DFG_JIT) |
| |
| #include "CodeBlock.h" |
| #include "DFGFailedFinalizer.h" |
| #include "DFGInlineCacheWrapperInlines.h" |
| #include "DFGJITCode.h" |
| #include "DFGJITFinalizer.h" |
| #include "DFGOSRExit.h" |
| #include "DFGOperations.h" |
| #include "DFGRegisterBank.h" |
| #include "DFGSlowPathGenerator.h" |
| #include "DFGSpeculativeJIT.h" |
| #include "DFGThunks.h" |
| #include "JSCInlines.h" |
| #include "JSCJSValueInlines.h" |
| #include "LinkBuffer.h" |
| #include "MaxFrameExtentForSlowPathCall.h" |
| #include "StructureStubInfo.h" |
| #include "ThunkGenerators.h" |
| #include "VM.h" |
| |
| namespace JSC { namespace DFG { |
| |
| JITCompiler::JITCompiler(Graph& dfg) |
| : CCallHelpers(dfg.m_codeBlock) |
| , m_graph(dfg) |
| , m_jitCode(adoptRef(new JITCode())) |
| , m_blockHeads(dfg.numBlocks()) |
| , m_pcToCodeOriginMapBuilder(dfg.m_vm) |
| { |
| if (UNLIKELY(shouldDumpDisassembly() || m_graph.m_vm.m_perBytecodeProfiler)) |
| m_disassembler = makeUnique<Disassembler>(dfg); |
| #if ENABLE(FTL_JIT) |
| m_jitCode->tierUpInLoopHierarchy = WTFMove(m_graph.m_plan.tierUpInLoopHierarchy()); |
| for (BytecodeIndex tierUpBytecode : m_graph.m_plan.tierUpAndOSREnterBytecodes()) |
| m_jitCode->tierUpEntryTriggers.add(tierUpBytecode, JITCode::TriggerReason::DontTrigger); |
| #endif |
| } |
| |
| JITCompiler::~JITCompiler() |
| { |
| } |
| |
| void JITCompiler::linkOSRExits() |
| { |
| ASSERT(m_jitCode->osrExit.size() == m_exitCompilationInfo.size()); |
| if (UNLIKELY(m_graph.compilation())) { |
| for (unsigned i = 0; i < m_jitCode->osrExit.size(); ++i) { |
| OSRExitCompilationInfo& info = m_exitCompilationInfo[i]; |
| Vector<Label> labels; |
| if (!info.m_failureJumps.empty()) { |
| for (unsigned j = 0; j < info.m_failureJumps.jumps().size(); ++j) |
| labels.append(info.m_failureJumps.jumps()[j].label()); |
| } else |
| labels.append(info.m_replacementSource); |
| m_exitSiteLabels.append(labels); |
| } |
| } |
| |
| for (unsigned i = 0; i < m_jitCode->osrExit.size(); ++i) { |
| OSRExitCompilationInfo& info = m_exitCompilationInfo[i]; |
| JumpList& failureJumps = info.m_failureJumps; |
| if (!failureJumps.empty()) |
| failureJumps.link(this); |
| else |
| info.m_replacementDestination = label(); |
| |
| jitAssertHasValidCallFrame(); |
| store32(TrustedImm32(i), &vm().osrExitIndex); |
| info.m_patchableJump = patchableJump(); |
| } |
| } |
| |
| void JITCompiler::compileEntry() |
| { |
| // This code currently matches the old JIT. In the function header we need to |
| // save return address and call frame via the prologue and perform a fast stack check. |
| // FIXME: https://bugs.webkit.org/show_bug.cgi?id=56292 |
| // We'll need to convert the remaining cti_ style calls (specifically the stack |
| // check) which will be dependent on stack layout. (We'd need to account for this in |
| // both normal return code and when jumping to an exception handler). |
| emitFunctionPrologue(); |
| emitPutToCallFrameHeader(m_codeBlock, CallFrameSlot::codeBlock); |
| } |
| |
| void JITCompiler::compileSetupRegistersForEntry() |
| { |
| emitSaveCalleeSaves(); |
| emitMaterializeTagCheckRegisters(); |
| } |
| |
| void JITCompiler::compileEntryExecutionFlag() |
| { |
| #if ENABLE(FTL_JIT) |
| if (m_graph.m_plan.canTierUpAndOSREnter()) |
| store8(TrustedImm32(0), &m_jitCode->neverExecutedEntry); |
| #endif // ENABLE(FTL_JIT) |
| } |
| |
| void JITCompiler::compileBody() |
| { |
| // We generate the speculative code path, followed by OSR exit code to return |
| // to the old JIT code if speculations fail. |
| |
| bool compiledSpeculative = m_speculative->compile(); |
| ASSERT_UNUSED(compiledSpeculative, compiledSpeculative); |
| } |
| |
| void JITCompiler::compileExceptionHandlers() |
| { |
| if (!m_exceptionChecksWithCallFrameRollback.empty()) { |
| m_exceptionChecksWithCallFrameRollback.link(this); |
| |
| copyCalleeSavesToEntryFrameCalleeSavesBuffer(vm().topEntryFrame); |
| |
| // operationLookupExceptionHandlerFromCallerFrame is passed one argument, the VM*. |
| move(TrustedImmPtr(&vm()), GPRInfo::argumentGPR0); |
| prepareCallOperation(vm()); |
| addPtr(TrustedImm32(m_graph.stackPointerOffset() * sizeof(Register)), GPRInfo::callFrameRegister, stackPointerRegister); |
| |
| m_calls.append(CallLinkRecord(call(OperationPtrTag), FunctionPtr<OperationPtrTag>(operationLookupExceptionHandlerFromCallerFrame))); |
| |
| jumpToExceptionHandler(vm()); |
| } |
| |
| if (!m_exceptionChecks.empty()) { |
| m_exceptionChecks.link(this); |
| |
| copyCalleeSavesToEntryFrameCalleeSavesBuffer(vm().topEntryFrame); |
| |
| // operationLookupExceptionHandler is passed one argument, the VM*. |
| move(TrustedImmPtr(&vm()), GPRInfo::argumentGPR0); |
| prepareCallOperation(vm()); |
| |
| m_calls.append(CallLinkRecord(call(OperationPtrTag), FunctionPtr<OperationPtrTag>(operationLookupExceptionHandler))); |
| |
| jumpToExceptionHandler(vm()); |
| } |
| } |
| |
| void JITCompiler::link(LinkBuffer& linkBuffer) |
| { |
| // Link the code, populate data in CodeBlock data structures. |
| m_jitCode->common.frameRegisterCount = m_graph.frameRegisterCount(); |
| m_jitCode->common.requiredRegisterCountForExit = m_graph.requiredRegisterCountForExit(); |
| |
| if (!m_graph.m_plan.inlineCallFrames()->isEmpty()) |
| m_jitCode->common.inlineCallFrames = m_graph.m_plan.inlineCallFrames(); |
| |
| #if USE(JSVALUE32_64) |
| m_jitCode->common.doubleConstants = WTFMove(m_graph.m_doubleConstants); |
| #endif |
| |
| m_graph.registerFrozenValues(); |
| |
| BitVector usedJumpTables; |
| for (Bag<SwitchData>::iterator iter = m_graph.m_switchData.begin(); !!iter; ++iter) { |
| SwitchData& data = **iter; |
| if (!data.didUseJumpTable) |
| continue; |
| |
| if (data.kind == SwitchString) |
| continue; |
| |
| RELEASE_ASSERT(data.kind == SwitchImm || data.kind == SwitchChar); |
| |
| usedJumpTables.set(data.switchTableIndex); |
| SimpleJumpTable& table = m_codeBlock->switchJumpTable(data.switchTableIndex); |
| table.ctiDefault = linkBuffer.locationOf<JSSwitchPtrTag>(m_blockHeads[data.fallThrough.block->index]); |
| table.ctiOffsets.grow(table.branchOffsets.size()); |
| for (unsigned j = table.ctiOffsets.size(); j--;) |
| table.ctiOffsets[j] = table.ctiDefault; |
| for (unsigned j = data.cases.size(); j--;) { |
| SwitchCase& myCase = data.cases[j]; |
| table.ctiOffsets[myCase.value.switchLookupValue(data.kind) - table.min] = |
| linkBuffer.locationOf<JSSwitchPtrTag>(m_blockHeads[myCase.target.block->index]); |
| } |
| } |
| |
| for (unsigned i = m_codeBlock->numberOfSwitchJumpTables(); i--;) { |
| if (usedJumpTables.get(i)) |
| continue; |
| |
| m_codeBlock->switchJumpTable(i).clear(); |
| } |
| |
| // NOTE: we cannot clear string switch tables because (1) we're running concurrently |
| // and we cannot deref StringImpl's and (2) it would be weird to deref those |
| // StringImpl's since we refer to them. |
| for (Bag<SwitchData>::iterator switchDataIter = m_graph.m_switchData.begin(); !!switchDataIter; ++switchDataIter) { |
| SwitchData& data = **switchDataIter; |
| if (!data.didUseJumpTable) |
| continue; |
| |
| if (data.kind != SwitchString) |
| continue; |
| |
| StringJumpTable& table = m_codeBlock->stringSwitchJumpTable(data.switchTableIndex); |
| |
| table.ctiDefault = linkBuffer.locationOf<JSSwitchPtrTag>(m_blockHeads[data.fallThrough.block->index]); |
| StringJumpTable::StringOffsetTable::iterator iter; |
| StringJumpTable::StringOffsetTable::iterator end = table.offsetTable.end(); |
| for (iter = table.offsetTable.begin(); iter != end; ++iter) |
| iter->value.ctiOffset = table.ctiDefault; |
| for (unsigned j = data.cases.size(); j--;) { |
| SwitchCase& myCase = data.cases[j]; |
| iter = table.offsetTable.find(myCase.value.stringImpl()); |
| RELEASE_ASSERT(iter != end); |
| iter->value.ctiOffset = linkBuffer.locationOf<JSSwitchPtrTag>(m_blockHeads[myCase.target.block->index]); |
| } |
| } |
| |
| // Link all calls out from the JIT code to their respective functions. |
| for (unsigned i = 0; i < m_calls.size(); ++i) |
| linkBuffer.link(m_calls[i].m_call, m_calls[i].m_function); |
| |
| finalizeInlineCaches(m_getByIds, linkBuffer); |
| finalizeInlineCaches(m_getByIdsWithThis, linkBuffer); |
| finalizeInlineCaches(m_getByVals, linkBuffer); |
| finalizeInlineCaches(m_putByIds, linkBuffer); |
| finalizeInlineCaches(m_delByIds, linkBuffer); |
| finalizeInlineCaches(m_delByVals, linkBuffer); |
| finalizeInlineCaches(m_inByIds, linkBuffer); |
| finalizeInlineCaches(m_instanceOfs, linkBuffer); |
| |
| auto linkCallThunk = FunctionPtr<NoPtrTag>(vm().getCTIStub(linkCallThunkGenerator).retaggedCode<NoPtrTag>()); |
| for (auto& record : m_jsCalls) { |
| CallLinkInfo& info = *record.info; |
| linkBuffer.link(record.slowCall, linkCallThunk); |
| info.setCallLocations( |
| CodeLocationLabel<JSInternalPtrTag>(linkBuffer.locationOfNearCall<JSInternalPtrTag>(record.slowCall)), |
| CodeLocationLabel<JSInternalPtrTag>(linkBuffer.locationOf<JSInternalPtrTag>(record.targetToCheck)), |
| linkBuffer.locationOfNearCall<JSInternalPtrTag>(record.fastCall)); |
| } |
| |
| for (JSDirectCallRecord& record : m_jsDirectCalls) { |
| CallLinkInfo& info = *record.info; |
| linkBuffer.link(record.call, linkBuffer.locationOf<NoPtrTag>(record.slowPath)); |
| info.setCallLocations( |
| CodeLocationLabel<JSInternalPtrTag>(), |
| linkBuffer.locationOf<JSInternalPtrTag>(record.slowPath), |
| linkBuffer.locationOfNearCall<JSInternalPtrTag>(record.call)); |
| } |
| |
| for (JSDirectTailCallRecord& record : m_jsDirectTailCalls) { |
| CallLinkInfo& info = *record.info; |
| info.setCallLocations( |
| linkBuffer.locationOf<JSInternalPtrTag>(record.patchableJump), |
| linkBuffer.locationOf<JSInternalPtrTag>(record.slowPath), |
| linkBuffer.locationOfNearCall<JSInternalPtrTag>(record.call)); |
| } |
| |
| MacroAssemblerCodeRef<JITThunkPtrTag> osrExitThunk = vm().getCTIStub(osrExitGenerationThunkGenerator); |
| auto target = CodeLocationLabel<JITThunkPtrTag>(osrExitThunk.code()); |
| for (unsigned i = 0; i < m_jitCode->osrExit.size(); ++i) { |
| OSRExitCompilationInfo& info = m_exitCompilationInfo[i]; |
| if (!Options::useProbeOSRExit()) { |
| linkBuffer.link(info.m_patchableJump.m_jump, target); |
| OSRExit& exit = m_jitCode->osrExit[i]; |
| exit.m_patchableJumpLocation = linkBuffer.locationOf<JSInternalPtrTag>(info.m_patchableJump); |
| } |
| if (info.m_replacementSource.isSet()) { |
| m_jitCode->common.jumpReplacements.append(JumpReplacement( |
| linkBuffer.locationOf<JSInternalPtrTag>(info.m_replacementSource), |
| linkBuffer.locationOf<OSRExitPtrTag>(info.m_replacementDestination))); |
| } |
| } |
| |
| if (UNLIKELY(m_graph.compilation())) { |
| ASSERT(m_exitSiteLabels.size() == m_jitCode->osrExit.size()); |
| for (unsigned i = 0; i < m_exitSiteLabels.size(); ++i) { |
| Vector<Label>& labels = m_exitSiteLabels[i]; |
| Vector<MacroAssemblerCodePtr<JSInternalPtrTag>> addresses; |
| for (unsigned j = 0; j < labels.size(); ++j) |
| addresses.append(linkBuffer.locationOf<JSInternalPtrTag>(labels[j])); |
| m_graph.compilation()->addOSRExitSite(addresses); |
| } |
| } else |
| ASSERT(!m_exitSiteLabels.size()); |
| |
| m_jitCode->common.compilation = m_graph.compilation(); |
| |
| // Link new DFG exception handlers and remove baseline JIT handlers. |
| m_codeBlock->clearExceptionHandlers(); |
| for (unsigned i = 0; i < m_exceptionHandlerOSRExitCallSites.size(); i++) { |
| OSRExitCompilationInfo& info = m_exceptionHandlerOSRExitCallSites[i].exitInfo; |
| if (info.m_replacementDestination.isSet()) { |
| // If this is is *not* set, it means that we already jumped to the OSR exit in pure generated control flow. |
| // i.e, we explicitly emitted an exceptionCheck that we know will be caught in this machine frame. |
| // If this *is set*, it means we will be landing at this code location from genericUnwind from an |
| // exception thrown in a child call frame. |
| CodeLocationLabel<ExceptionHandlerPtrTag> catchLabel = linkBuffer.locationOf<ExceptionHandlerPtrTag>(info.m_replacementDestination); |
| HandlerInfo newExceptionHandler = m_exceptionHandlerOSRExitCallSites[i].baselineExceptionHandler; |
| CallSiteIndex callSite = m_exceptionHandlerOSRExitCallSites[i].callSiteIndex; |
| newExceptionHandler.start = callSite.bits(); |
| newExceptionHandler.end = callSite.bits() + 1; |
| newExceptionHandler.nativeCode = catchLabel; |
| m_codeBlock->appendExceptionHandler(newExceptionHandler); |
| } |
| } |
| |
| if (m_pcToCodeOriginMapBuilder.didBuildMapping()) |
| m_codeBlock->setPCToCodeOriginMap(makeUnique<PCToCodeOriginMap>(WTFMove(m_pcToCodeOriginMapBuilder), linkBuffer)); |
| } |
| |
| static void emitStackOverflowCheck(JITCompiler& jit, MacroAssembler::JumpList& stackOverflow) |
| { |
| int frameTopOffset = virtualRegisterForLocal(jit.graph().requiredRegisterCountForExecutionAndExit() - 1).offset() * sizeof(Register); |
| unsigned maxFrameSize = -frameTopOffset; |
| |
| jit.addPtr(MacroAssembler::TrustedImm32(frameTopOffset), GPRInfo::callFrameRegister, GPRInfo::regT1); |
| if (UNLIKELY(maxFrameSize > Options::reservedZoneSize())) |
| stackOverflow.append(jit.branchPtr(MacroAssembler::Above, GPRInfo::regT1, GPRInfo::callFrameRegister)); |
| stackOverflow.append(jit.branchPtr(MacroAssembler::Above, MacroAssembler::AbsoluteAddress(jit.vm().addressOfSoftStackLimit()), GPRInfo::regT1)); |
| } |
| |
| void JITCompiler::compile() |
| { |
| makeCatchOSREntryBuffer(); |
| |
| setStartOfCode(); |
| compileEntry(); |
| m_speculative = makeUnique<SpeculativeJIT>(*this); |
| |
| // Plant a check that sufficient space is available in the JSStack. |
| JumpList stackOverflow; |
| emitStackOverflowCheck(*this, stackOverflow); |
| |
| addPtr(TrustedImm32(-(m_graph.frameRegisterCount() * sizeof(Register))), GPRInfo::callFrameRegister, stackPointerRegister); |
| checkStackPointerAlignment(); |
| compileSetupRegistersForEntry(); |
| compileEntryExecutionFlag(); |
| compileBody(); |
| setEndOfMainPath(); |
| |
| // === Footer code generation === |
| // |
| // Generate the stack overflow handling; if the stack check in the entry head fails, |
| // we need to call out to a helper function to throw the StackOverflowError. |
| stackOverflow.link(this); |
| |
| emitStoreCodeOrigin(CodeOrigin(BytecodeIndex(0))); |
| |
| if (maxFrameExtentForSlowPathCall) |
| addPtr(TrustedImm32(-static_cast<int32_t>(maxFrameExtentForSlowPathCall)), stackPointerRegister); |
| |
| m_speculative->callOperationWithCallFrameRollbackOnException(operationThrowStackOverflowError, m_codeBlock); |
| |
| // Generate slow path code. |
| m_speculative->runSlowPathGenerators(m_pcToCodeOriginMapBuilder); |
| m_pcToCodeOriginMapBuilder.appendItem(labelIgnoringWatchpoints(), PCToCodeOriginMapBuilder::defaultCodeOrigin()); |
| |
| compileExceptionHandlers(); |
| linkOSRExits(); |
| |
| // Create OSR entry trampolines if necessary. |
| m_speculative->createOSREntries(); |
| setEndOfCode(); |
| |
| auto linkBuffer = makeUnique<LinkBuffer>(*this, m_codeBlock, JITCompilationCanFail); |
| if (linkBuffer->didFailToAllocate()) { |
| m_graph.m_plan.setFinalizer(makeUnique<FailedFinalizer>(m_graph.m_plan)); |
| return; |
| } |
| |
| link(*linkBuffer); |
| m_speculative->linkOSREntries(*linkBuffer); |
| |
| disassemble(*linkBuffer); |
| |
| m_graph.m_plan.setFinalizer(makeUnique<JITFinalizer>( |
| m_graph.m_plan, m_jitCode.releaseNonNull(), WTFMove(linkBuffer))); |
| } |
| |
| void JITCompiler::compileFunction() |
| { |
| makeCatchOSREntryBuffer(); |
| |
| setStartOfCode(); |
| Label entryLabel(this); |
| 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. |
| JumpList stackOverflow; |
| emitStackOverflowCheck(*this, stackOverflow); |
| |
| // Move the stack pointer down to accommodate locals |
| addPtr(TrustedImm32(-(m_graph.frameRegisterCount() * sizeof(Register))), GPRInfo::callFrameRegister, stackPointerRegister); |
| checkStackPointerAlignment(); |
| |
| compileSetupRegistersForEntry(); |
| compileEntryExecutionFlag(); |
| |
| // === Function body code generation === |
| m_speculative = makeUnique<SpeculativeJIT>(*this); |
| compileBody(); |
| setEndOfMainPath(); |
| |
| // === Function footer code generation === |
| // |
| // Generate code to perform the stack overflow handling (if the stack check in |
| // the function header fails), and generate the entry point with arity check. |
| // |
| // Generate the stack overflow handling; if the stack check in the function head fails, |
| // we need to call out to a helper function to throw the StackOverflowError. |
| stackOverflow.link(this); |
| |
| emitStoreCodeOrigin(CodeOrigin(BytecodeIndex(0))); |
| |
| if (maxFrameExtentForSlowPathCall) |
| addPtr(TrustedImm32(-static_cast<int32_t>(maxFrameExtentForSlowPathCall)), stackPointerRegister); |
| |
| m_speculative->callOperationWithCallFrameRollbackOnException(operationThrowStackOverflowError, m_codeBlock); |
| |
| // 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). |
| Call callArityFixup; |
| Label arityCheck; |
| bool requiresArityFixup = m_codeBlock->numParameters() != 1; |
| if (requiresArityFixup) { |
| arityCheck = label(); |
| compileEntry(); |
| |
| load32(AssemblyHelpers::payloadFor((VirtualRegister)CallFrameSlot::argumentCountIncludingThis), GPRInfo::regT1); |
| branch32(AboveOrEqual, GPRInfo::regT1, TrustedImm32(m_codeBlock->numParameters())).linkTo(fromArityCheck, this); |
| emitStoreCodeOrigin(CodeOrigin(BytecodeIndex(0))); |
| if (maxFrameExtentForSlowPathCall) |
| addPtr(TrustedImm32(-static_cast<int32_t>(maxFrameExtentForSlowPathCall)), stackPointerRegister); |
| m_speculative->callOperationWithCallFrameRollbackOnException(m_codeBlock->isConstructor() ? operationConstructArityCheck : operationCallArityCheck, GPRInfo::regT0, m_codeBlock->globalObject()); |
| if (maxFrameExtentForSlowPathCall) |
| addPtr(TrustedImm32(maxFrameExtentForSlowPathCall), stackPointerRegister); |
| branchTest32(Zero, GPRInfo::returnValueGPR).linkTo(fromArityCheck, this); |
| emitStoreCodeOrigin(CodeOrigin(BytecodeIndex(0))); |
| move(GPRInfo::returnValueGPR, GPRInfo::argumentGPR0); |
| callArityFixup = nearCall(); |
| jump(fromArityCheck); |
| } else |
| arityCheck = entryLabel; |
| |
| // Generate slow path code. |
| m_speculative->runSlowPathGenerators(m_pcToCodeOriginMapBuilder); |
| m_pcToCodeOriginMapBuilder.appendItem(labelIgnoringWatchpoints(), PCToCodeOriginMapBuilder::defaultCodeOrigin()); |
| |
| compileExceptionHandlers(); |
| linkOSRExits(); |
| |
| // Create OSR entry trampolines if necessary. |
| m_speculative->createOSREntries(); |
| setEndOfCode(); |
| |
| // === Link === |
| auto linkBuffer = makeUnique<LinkBuffer>(*this, m_codeBlock, JITCompilationCanFail); |
| if (linkBuffer->didFailToAllocate()) { |
| m_graph.m_plan.setFinalizer(makeUnique<FailedFinalizer>(m_graph.m_plan)); |
| return; |
| } |
| link(*linkBuffer); |
| m_speculative->linkOSREntries(*linkBuffer); |
| |
| if (requiresArityFixup) |
| linkBuffer->link(callArityFixup, FunctionPtr<JITThunkPtrTag>(vm().getCTIStub(arityFixupGenerator).code())); |
| |
| disassemble(*linkBuffer); |
| |
| MacroAssemblerCodePtr<JSEntryPtrTag> withArityCheck = linkBuffer->locationOf<JSEntryPtrTag>(arityCheck); |
| |
| m_graph.m_plan.setFinalizer(makeUnique<JITFinalizer>( |
| m_graph.m_plan, m_jitCode.releaseNonNull(), WTFMove(linkBuffer), withArityCheck)); |
| } |
| |
| void JITCompiler::disassemble(LinkBuffer& linkBuffer) |
| { |
| if (shouldDumpDisassembly()) { |
| m_disassembler->dump(linkBuffer); |
| linkBuffer.didAlreadyDisassemble(); |
| } |
| |
| if (UNLIKELY(m_graph.m_plan.compilation())) |
| m_disassembler->reportToProfiler(m_graph.m_plan.compilation(), linkBuffer); |
| } |
| |
| #if USE(JSVALUE32_64) |
| void* JITCompiler::addressOfDoubleConstant(Node* node) |
| { |
| double value = node->asNumber(); |
| int64_t valueBits = bitwise_cast<int64_t>(value); |
| auto it = m_graph.m_doubleConstantsMap.find(valueBits); |
| if (it != m_graph.m_doubleConstantsMap.end()) |
| return it->second; |
| |
| if (!m_graph.m_doubleConstants) |
| m_graph.m_doubleConstants = makeUnique<Bag<double>>(); |
| |
| double* addressInConstantPool = m_graph.m_doubleConstants->add(); |
| *addressInConstantPool = value; |
| m_graph.m_doubleConstantsMap[valueBits] = addressInConstantPool; |
| return addressInConstantPool; |
| } |
| #endif |
| |
| void JITCompiler::noticeCatchEntrypoint(BasicBlock& basicBlock, JITCompiler::Label blockHead, LinkBuffer& linkBuffer, Vector<FlushFormat>&& argumentFormats) |
| { |
| RELEASE_ASSERT(basicBlock.isCatchEntrypoint); |
| RELEASE_ASSERT(basicBlock.intersectionOfCFAHasVisited); // An entrypoint is reachable by definition. |
| m_jitCode->common.appendCatchEntrypoint(basicBlock.bytecodeBegin, linkBuffer.locationOf<ExceptionHandlerPtrTag>(blockHead), WTFMove(argumentFormats)); |
| } |
| |
| void JITCompiler::noticeOSREntry(BasicBlock& basicBlock, JITCompiler::Label blockHead, LinkBuffer& linkBuffer) |
| { |
| RELEASE_ASSERT(!basicBlock.isCatchEntrypoint); |
| |
| // OSR entry is not allowed into blocks deemed unreachable by control flow analysis. |
| if (!basicBlock.intersectionOfCFAHasVisited) |
| return; |
| |
| OSREntryData* entry = m_jitCode->appendOSREntryData(basicBlock.bytecodeBegin, linkBuffer.locationOf<OSREntryPtrTag>(blockHead)); |
| |
| entry->m_expectedValues = basicBlock.intersectionOfPastValuesAtHead; |
| |
| // Fix the expected values: in our protocol, a dead variable will have an expected |
| // value of (None, []). But the old JIT may stash some values there. So we really |
| // need (Top, TOP). |
| for (size_t argument = 0; argument < basicBlock.variablesAtHead.numberOfArguments(); ++argument) { |
| Node* node = basicBlock.variablesAtHead.argument(argument); |
| if (!node || !node->shouldGenerate()) |
| entry->m_expectedValues.argument(argument).makeBytecodeTop(); |
| } |
| for (size_t local = 0; local < basicBlock.variablesAtHead.numberOfLocals(); ++local) { |
| Node* node = basicBlock.variablesAtHead.local(local); |
| if (!node || !node->shouldGenerate()) |
| entry->m_expectedValues.local(local).makeBytecodeTop(); |
| else { |
| VariableAccessData* variable = node->variableAccessData(); |
| entry->m_machineStackUsed.set(variable->machineLocal().toLocal()); |
| |
| switch (variable->flushFormat()) { |
| case FlushedDouble: |
| entry->m_localsForcedDouble.set(local); |
| break; |
| case FlushedInt52: |
| entry->m_localsForcedAnyInt.set(local); |
| break; |
| default: |
| break; |
| } |
| |
| ASSERT(!variable->operand().isTmp()); |
| if (variable->operand().virtualRegister() != variable->machineLocal()) { |
| entry->m_reshufflings.append( |
| OSREntryReshuffling( |
| variable->operand().virtualRegister().offset(), variable->machineLocal().offset())); |
| } |
| } |
| } |
| |
| entry->m_reshufflings.shrinkToFit(); |
| } |
| |
| void JITCompiler::appendExceptionHandlingOSRExit(ExitKind kind, unsigned eventStreamIndex, CodeOrigin opCatchOrigin, HandlerInfo* exceptionHandler, CallSiteIndex callSite, MacroAssembler::JumpList jumpsToFail) |
| { |
| OSRExit exit(kind, JSValueRegs(), MethodOfGettingAValueProfile(), m_speculative.get(), eventStreamIndex); |
| exit.m_codeOrigin = opCatchOrigin; |
| exit.m_exceptionHandlerCallSiteIndex = callSite; |
| OSRExitCompilationInfo& exitInfo = appendExitInfo(jumpsToFail); |
| jitCode()->appendOSRExit(exit); |
| m_exceptionHandlerOSRExitCallSites.append(ExceptionHandlingOSRExitInfo { exitInfo, *exceptionHandler, callSite }); |
| } |
| |
| void JITCompiler::exceptionCheck() |
| { |
| // It's important that we use origin.forExit here. Consider if we hoist string |
| // addition outside a loop, and that we exit at the point of that concatenation |
| // from an out of memory exception. |
| // If the original loop had a try/catch around string concatenation, if we "catch" |
| // that exception inside the loop, then the loops induction variable will be undefined |
| // in the OSR exit value recovery. It's more defensible for the string concatenation, |
| // then, to not be caught by the for loops' try/catch. |
| // Here is the program I'm speaking about: |
| // |
| // >>>> lets presume "c = a + b" gets hoisted here. |
| // for (var i = 0; i < length; i++) { |
| // try { |
| // c = a + b |
| // } catch(e) { |
| // If we threw an out of memory error, and we cought the exception |
| // right here, then "i" would almost certainly be undefined, which |
| // would make no sense. |
| // ... |
| // } |
| // } |
| CodeOrigin opCatchOrigin; |
| HandlerInfo* exceptionHandler; |
| bool willCatchException = m_graph.willCatchExceptionInMachineFrame(m_speculative->m_currentNode->origin.forExit, opCatchOrigin, exceptionHandler); |
| if (willCatchException) { |
| unsigned streamIndex = m_speculative->m_outOfLineStreamIndex ? *m_speculative->m_outOfLineStreamIndex : m_speculative->m_stream->size(); |
| MacroAssembler::Jump hadException = emitNonPatchableExceptionCheck(vm()); |
| // We assume here that this is called after callOpeartion()/appendCall() is called. |
| appendExceptionHandlingOSRExit(ExceptionCheck, streamIndex, opCatchOrigin, exceptionHandler, m_jitCode->common.lastCallSite(), hadException); |
| } else |
| m_exceptionChecks.append(emitExceptionCheck(vm())); |
| } |
| |
| CallSiteIndex JITCompiler::recordCallSiteAndGenerateExceptionHandlingOSRExitIfNeeded(const CodeOrigin& callSiteCodeOrigin, unsigned eventStreamIndex) |
| { |
| CodeOrigin opCatchOrigin; |
| HandlerInfo* exceptionHandler; |
| bool willCatchException = m_graph.willCatchExceptionInMachineFrame(callSiteCodeOrigin, opCatchOrigin, exceptionHandler); |
| CallSiteIndex callSite = addCallSite(callSiteCodeOrigin); |
| if (willCatchException) |
| appendExceptionHandlingOSRExit(GenericUnwind, eventStreamIndex, opCatchOrigin, exceptionHandler, callSite); |
| return callSite; |
| } |
| |
| void JITCompiler::setEndOfMainPath() |
| { |
| m_pcToCodeOriginMapBuilder.appendItem(labelIgnoringWatchpoints(), m_speculative->m_origin.semantic); |
| if (LIKELY(!m_disassembler)) |
| return; |
| m_disassembler->setEndOfMainPath(labelIgnoringWatchpoints()); |
| } |
| |
| void JITCompiler::setEndOfCode() |
| { |
| m_pcToCodeOriginMapBuilder.appendItem(labelIgnoringWatchpoints(), PCToCodeOriginMapBuilder::defaultCodeOrigin()); |
| if (LIKELY(!m_disassembler)) |
| return; |
| m_disassembler->setEndOfCode(labelIgnoringWatchpoints()); |
| } |
| |
| void JITCompiler::makeCatchOSREntryBuffer() |
| { |
| if (m_graph.m_maxLocalsForCatchOSREntry) { |
| uint32_t numberOfLiveLocals = std::max(*m_graph.m_maxLocalsForCatchOSREntry, 1u); // Make sure we always allocate a non-null catchOSREntryBuffer. |
| m_jitCode->common.catchOSREntryBuffer = vm().scratchBufferForSize(sizeof(JSValue) * numberOfLiveLocals); |
| } |
| } |
| |
| } } // namespace JSC::DFG |
| |
| #endif // ENABLE(DFG_JIT) |
