| /* |
| * Copyright (C) 2012-2018 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 "CallLinkInfo.h" |
| |
| #include "CCallHelpers.h" |
| #include "CallFrameShuffleData.h" |
| #include "DisallowMacroScratchRegisterUsage.h" |
| #include "FunctionCodeBlock.h" |
| #include "JSCellInlines.h" |
| #include "LinkBuffer.h" |
| #include "Opcode.h" |
| #include "Repatch.h" |
| #include "ThunkGenerators.h" |
| #include <wtf/ListDump.h> |
| |
| namespace JSC { |
| |
| CallLinkInfo::CallType CallLinkInfo::callTypeFor(OpcodeID opcodeID) |
| { |
| switch (opcodeID) { |
| case op_tail_call_varargs: |
| case op_tail_call_forward_arguments: |
| return TailCallVarargs; |
| |
| case op_call: |
| case op_call_eval: |
| case op_iterator_open: |
| case op_iterator_next: |
| return Call; |
| |
| case op_call_varargs: |
| return CallVarargs; |
| |
| case op_construct: |
| return Construct; |
| |
| case op_construct_varargs: |
| return ConstructVarargs; |
| |
| case op_tail_call: |
| return TailCall; |
| |
| default: |
| break; |
| } |
| RELEASE_ASSERT_NOT_REACHED(); |
| return Call; |
| } |
| |
| CallLinkInfo::~CallLinkInfo() |
| { |
| clearStub(); |
| |
| if (isOnList()) |
| remove(); |
| } |
| |
| void CallLinkInfo::clearStub() |
| { |
| #if ENABLE(JIT) |
| if (!stub()) |
| return; |
| |
| m_stub->clearCallNodesFor(this); |
| m_stub = nullptr; |
| #endif |
| } |
| |
| void CallLinkInfo::unlink(VM& vm) |
| { |
| // We could be called even if we're not linked anymore because of how polymorphic calls |
| // work. Each callsite within the polymorphic call stub may separately ask us to unlink(). |
| if (isLinked()) |
| unlinkCall(vm, *this); |
| |
| // Either we were unlinked, in which case we should not have been on any list, or we unlinked |
| // ourselves so that we're not on any list anymore. |
| RELEASE_ASSERT(!isOnList()); |
| } |
| |
| CodeLocationLabel<JSInternalPtrTag> CallLinkInfo::doneLocation() |
| { |
| RELEASE_ASSERT(!isDirect()); |
| return m_doneLocation; |
| } |
| |
| void CallLinkInfo::setMonomorphicCallee(VM& vm, JSCell* owner, JSObject* callee, CodeBlock* codeBlock, MacroAssemblerCodePtr<JSEntryPtrTag> codePtr) |
| { |
| RELEASE_ASSERT(!isDirect()); |
| RELEASE_ASSERT(!(bitwise_cast<uintptr_t>(callee) & polymorphicCalleeMask)); |
| m_calleeOrCodeBlock.set(vm, owner, callee); |
| |
| if (isDataIC()) { |
| u.dataIC.m_codeBlock = codeBlock; |
| u.dataIC.m_monomorphicCallDestination = codePtr; |
| } else { |
| #if ENABLE(JIT) |
| MacroAssembler::repatchNearCall(static_cast<OptimizingCallLinkInfo*>(this)->m_callLocation, CodeLocationLabel<JSEntryPtrTag>(codePtr)); |
| MacroAssembler::repatchPointer(u.codeIC.m_codeBlockLocation, codeBlock); |
| MacroAssembler::repatchPointer(u.codeIC.m_calleeLocation, callee); |
| #else |
| RELEASE_ASSERT_NOT_REACHED(); |
| #endif |
| } |
| } |
| |
| void CallLinkInfo::clearCallee() |
| { |
| RELEASE_ASSERT(!isDirect()); |
| m_calleeOrCodeBlock.clear(); |
| if (isDataIC()) { |
| u.dataIC.m_codeBlock = nullptr; |
| u.dataIC.m_monomorphicCallDestination = nullptr; |
| } else if (!clearedByJettison()) { |
| #if ENABLE(JIT) |
| MacroAssembler::repatchPointer(u.codeIC.m_codeBlockLocation, nullptr); |
| MacroAssembler::repatchPointer(u.codeIC.m_calleeLocation, nullptr); |
| #else |
| RELEASE_ASSERT_NOT_REACHED(); |
| #endif |
| } |
| } |
| |
| JSObject* CallLinkInfo::callee() |
| { |
| RELEASE_ASSERT(!isDirect()); |
| RELEASE_ASSERT(!(bitwise_cast<uintptr_t>(m_calleeOrCodeBlock.get()) & polymorphicCalleeMask)); |
| return jsCast<JSObject*>(m_calleeOrCodeBlock.get()); |
| } |
| |
| void CallLinkInfo::setCodeBlock(VM& vm, JSCell* owner, FunctionCodeBlock* codeBlock) |
| { |
| RELEASE_ASSERT(isDirect()); |
| m_calleeOrCodeBlock.setMayBeNull(vm, owner, codeBlock); |
| } |
| |
| void CallLinkInfo::clearCodeBlock() |
| { |
| RELEASE_ASSERT(isDirect()); |
| m_calleeOrCodeBlock.clear(); |
| } |
| |
| FunctionCodeBlock* CallLinkInfo::codeBlock() |
| { |
| RELEASE_ASSERT(isDirect()); |
| return jsCast<FunctionCodeBlock*>(m_calleeOrCodeBlock.get()); |
| } |
| |
| void CallLinkInfo::setLastSeenCallee(VM& vm, const JSCell* owner, JSObject* callee) |
| { |
| RELEASE_ASSERT(!isDirect()); |
| m_lastSeenCalleeOrExecutable.set(vm, owner, callee); |
| } |
| |
| void CallLinkInfo::clearLastSeenCallee() |
| { |
| RELEASE_ASSERT(!isDirect()); |
| m_lastSeenCalleeOrExecutable.clear(); |
| } |
| |
| JSObject* CallLinkInfo::lastSeenCallee() const |
| { |
| RELEASE_ASSERT(!isDirect()); |
| return jsCast<JSObject*>(m_lastSeenCalleeOrExecutable.get()); |
| } |
| |
| bool CallLinkInfo::haveLastSeenCallee() const |
| { |
| RELEASE_ASSERT(!isDirect()); |
| return !!m_lastSeenCalleeOrExecutable; |
| } |
| |
| void CallLinkInfo::setExecutableDuringCompilation(ExecutableBase* executable) |
| { |
| RELEASE_ASSERT(isDirect()); |
| m_lastSeenCalleeOrExecutable.setWithoutWriteBarrier(executable); |
| } |
| |
| ExecutableBase* CallLinkInfo::executable() |
| { |
| RELEASE_ASSERT(isDirect()); |
| return jsCast<ExecutableBase*>(m_lastSeenCalleeOrExecutable.get()); |
| } |
| |
| void CallLinkInfo::setMaxArgumentCountIncludingThis(unsigned value) |
| { |
| RELEASE_ASSERT(isDirect()); |
| RELEASE_ASSERT(value); |
| m_maxArgumentCountIncludingThis = value; |
| } |
| |
| void CallLinkInfo::visitWeak(VM& vm) |
| { |
| auto handleSpecificCallee = [&] (JSFunction* callee) { |
| if (vm.heap.isMarked(callee->executable())) |
| m_hasSeenClosure = true; |
| else |
| m_clearedByGC = true; |
| }; |
| |
| if (isLinked()) { |
| if (stub()) { |
| #if ENABLE(JIT) |
| if (!stub()->visitWeak(vm)) { |
| if (UNLIKELY(Options::verboseOSR())) { |
| dataLog( |
| "At ", m_codeOrigin, ", ", RawPointer(this), ": clearing call stub to ", |
| listDump(stub()->variants()), ", stub routine ", RawPointer(stub()), |
| ".\n"); |
| } |
| unlink(vm); |
| m_clearedByGC = true; |
| } |
| #else |
| RELEASE_ASSERT_NOT_REACHED(); |
| #endif |
| } else if (!vm.heap.isMarked(m_calleeOrCodeBlock.get())) { |
| if (isDirect()) { |
| if (UNLIKELY(Options::verboseOSR())) { |
| dataLog( |
| "Clearing call to ", RawPointer(codeBlock()), " (", |
| pointerDump(codeBlock()), ").\n"); |
| } |
| } else { |
| JSObject* callee = jsCast<JSObject*>(m_calleeOrCodeBlock.get()); |
| if (callee->type() == JSFunctionType) { |
| if (UNLIKELY(Options::verboseOSR())) { |
| dataLog( |
| "Clearing call to ", |
| RawPointer(callee), " (", |
| static_cast<JSFunction*>(callee)->executable()->hashFor(specializationKind()), |
| ").\n"); |
| } |
| handleSpecificCallee(static_cast<JSFunction*>(callee)); |
| } else { |
| if (UNLIKELY(Options::verboseOSR())) |
| dataLog("Clearing call to ", RawPointer(callee), ".\n"); |
| m_clearedByGC = true; |
| } |
| } |
| unlink(vm); |
| } else if (isDirect() && !vm.heap.isMarked(m_lastSeenCalleeOrExecutable.get())) { |
| if (UNLIKELY(Options::verboseOSR())) { |
| dataLog( |
| "Clearing call to ", RawPointer(executable()), |
| " because the executable is dead.\n"); |
| } |
| unlink(vm); |
| // We should only get here once the owning CodeBlock is dying, since the executable must |
| // already be in the owner's weak references. |
| m_lastSeenCalleeOrExecutable.clear(); |
| } |
| } |
| if (!isDirect() && haveLastSeenCallee() && !vm.heap.isMarked(lastSeenCallee())) { |
| if (lastSeenCallee()->type() == JSFunctionType) |
| handleSpecificCallee(jsCast<JSFunction*>(lastSeenCallee())); |
| else |
| m_clearedByGC = true; |
| clearLastSeenCallee(); |
| } |
| } |
| |
| void CallLinkInfo::setSlowPathCallDestination(MacroAssemblerCodePtr<JSEntryPtrTag> codePtr) |
| { |
| m_slowPathCallDestination = codePtr; |
| } |
| |
| void CallLinkInfo::revertCallToStub() |
| { |
| RELEASE_ASSERT(stub()); |
| // The start of our JIT code is now a jump to the polymorphic stub. Rewrite the first instruction |
| // to be what we need for non stub ICs. |
| |
| // this runs into some branch compaction crap I'd like to avoid for now. Essentially, the branch |
| // doesn't know if it can be compacted or not. So we end up with 28 bytes of machine code, for |
| // what in all likelihood fits in 24. So we just splat out the first instruction. Long term, we |
| // need something cleaner. But this works on arm64 for now. |
| |
| if (isDataIC()) { |
| m_calleeOrCodeBlock.clear(); |
| u.dataIC.m_codeBlock = nullptr; |
| u.dataIC.m_monomorphicCallDestination = nullptr; |
| } else { |
| #if ENABLE(JIT) |
| MacroAssembler::repatchPointer(u.codeIC.m_codeBlockLocation, nullptr); |
| CCallHelpers::revertJumpReplacementToBranchPtrWithPatch( |
| CCallHelpers::startOfBranchPtrWithPatchOnRegister(u.codeIC.m_calleeLocation), calleeGPR(), nullptr); |
| #else |
| RELEASE_ASSERT_NOT_REACHED(); |
| #endif |
| } |
| } |
| |
| void BaselineCallLinkInfo::initialize(VM& vm, CallType callType, BytecodeIndex bytecodeIndex) |
| { |
| m_type = static_cast<unsigned>(Type::Baseline); |
| ASSERT(Type::Baseline == type()); |
| m_useDataIC = static_cast<unsigned>(UseDataIC::Yes); |
| ASSERT(UseDataIC::Yes == useDataIC()); |
| m_codeOrigin = CodeOrigin(bytecodeIndex); |
| m_callType = callType; |
| if (LIKELY(Options::useLLIntICs())) |
| setSlowPathCallDestination(vm.getCTILinkCall().code()); |
| else |
| setSlowPathCallDestination(vm.getCTIVirtualCall(callMode()).retagged<JSEntryPtrTag>().code()); |
| // If JIT is disabled, we should not support dynamically generated call IC. |
| if (!Options::useJIT()) |
| disallowStubs(); |
| } |
| |
| #if ENABLE(JIT) |
| |
| void OptimizingCallLinkInfo::setFrameShuffleData(const CallFrameShuffleData& shuffleData) |
| { |
| m_frameShuffleData = makeUnique<CallFrameShuffleData>(shuffleData); |
| m_frameShuffleData->shrinkToFit(); |
| } |
| |
| MacroAssembler::JumpList CallLinkInfo::emitFastPathImpl(CallLinkInfo* callLinkInfo, CCallHelpers& jit, GPRReg calleeGPR, GPRReg callLinkInfoGPR, UseDataIC useDataIC, bool isTailCall, ScopedLambda<void()>&& prepareForTailCall) |
| { |
| CCallHelpers::JumpList slowPath; |
| |
| if (useDataIC == UseDataIC::Yes) { |
| CCallHelpers::Jump goPolymorphic; |
| |
| // For RISCV64, scratch register usage here collides with MacroAssembler's internal usage |
| // that's necessary for the test-and-branch operation but is avoidable by loading from the callee |
| // address for each branch operation. Other MacroAssembler implementations handle this better by |
| // using a wider range of scratch registers or more potent branching instructions. |
| if constexpr (isRISCV64()) { |
| CCallHelpers::Address calleeAddress(callLinkInfoGPR, offsetOfCallee()); |
| goPolymorphic = jit.branchTestPtr(CCallHelpers::NonZero, calleeAddress, CCallHelpers::TrustedImm32(polymorphicCalleeMask)); |
| slowPath.append(jit.branchPtr(CCallHelpers::NotEqual, calleeAddress, calleeGPR)); |
| } else { |
| GPRReg scratchGPR = jit.scratchRegister(); |
| DisallowMacroScratchRegisterUsage disallowScratch(jit); |
| jit.loadPtr(CCallHelpers::Address(callLinkInfoGPR, offsetOfCallee()), scratchGPR); |
| goPolymorphic = jit.branchTestPtr(CCallHelpers::NonZero, scratchGPR, CCallHelpers::TrustedImm32(polymorphicCalleeMask)); |
| slowPath.append(jit.branchPtr(CCallHelpers::NotEqual, scratchGPR, calleeGPR)); |
| } |
| |
| if (isTailCall) { |
| prepareForTailCall(); |
| |
| GPRReg scratchGPR = CCallHelpers::selectScratchGPR(calleeGPR, callLinkInfoGPR); |
| jit.loadPtr(CCallHelpers::Address(callLinkInfoGPR, offsetOfCodeBlock()), scratchGPR); |
| jit.storePtr(scratchGPR, CCallHelpers::calleeFrameCodeBlockBeforeTailCall()); |
| |
| goPolymorphic.link(&jit); // Polymorphic stub handles tail call stack prep. |
| jit.farJump(CCallHelpers::Address(callLinkInfoGPR, offsetOfMonomorphicCallDestination()), JSEntryPtrTag); |
| } else { |
| GPRReg scratchGPR = CCallHelpers::selectScratchGPR(calleeGPR, callLinkInfoGPR); |
| jit.loadPtr(CCallHelpers::Address(callLinkInfoGPR, offsetOfCodeBlock()), scratchGPR); |
| jit.storePtr(scratchGPR, CCallHelpers::calleeFrameCodeBlockBeforeCall()); |
| |
| goPolymorphic.link(&jit); |
| jit.call(CCallHelpers::Address(callLinkInfoGPR, offsetOfMonomorphicCallDestination()), JSEntryPtrTag); |
| } |
| } else { |
| CCallHelpers::DataLabelPtr calleeCheck; |
| slowPath.append(jit.branchPtrWithPatch(CCallHelpers::NotEqual, calleeGPR, calleeCheck, CCallHelpers::TrustedImmPtr(nullptr))); |
| |
| CCallHelpers::Call call; |
| CCallHelpers::DataLabelPtr codeBlockStore; |
| if (isTailCall) { |
| prepareForTailCall(); |
| codeBlockStore = jit.storePtrWithPatch(CCallHelpers::TrustedImmPtr(nullptr), CCallHelpers::calleeFrameCodeBlockBeforeTailCall()); |
| call = jit.nearTailCall(); |
| } else { |
| codeBlockStore = jit.storePtrWithPatch(CCallHelpers::TrustedImmPtr(nullptr), CCallHelpers::calleeFrameCodeBlockBeforeCall()); |
| call = jit.nearCall(); |
| } |
| |
| RELEASE_ASSERT(callLinkInfo); |
| jit.addLinkTask([=] (LinkBuffer& linkBuffer) { |
| static_cast<OptimizingCallLinkInfo*>(callLinkInfo)->m_callLocation = linkBuffer.locationOfNearCall<JSInternalPtrTag>(call); |
| callLinkInfo->u.codeIC.m_codeBlockLocation = linkBuffer.locationOf<JSInternalPtrTag>(codeBlockStore); |
| callLinkInfo->u.codeIC.m_calleeLocation = linkBuffer.locationOf<JSInternalPtrTag>(calleeCheck); |
| }); |
| } |
| |
| return slowPath; |
| } |
| |
| MacroAssembler::JumpList CallLinkInfo::emitDataICFastPath(CCallHelpers& jit, GPRReg calleeGPR, GPRReg callLinkInfoGPR) |
| { |
| RELEASE_ASSERT(callLinkInfoGPR != InvalidGPRReg); |
| return emitFastPathImpl(nullptr, jit, calleeGPR, callLinkInfoGPR, UseDataIC::Yes, false, nullptr); |
| } |
| |
| MacroAssembler::JumpList CallLinkInfo::emitTailCallDataICFastPath(CCallHelpers& jit, GPRReg calleeGPR, GPRReg callLinkInfoGPR, ScopedLambda<void()>&& prepareForTailCall) |
| { |
| RELEASE_ASSERT(callLinkInfoGPR != InvalidGPRReg); |
| return emitFastPathImpl(nullptr, jit, calleeGPR, callLinkInfoGPR, UseDataIC::Yes, true, WTFMove(prepareForTailCall)); |
| } |
| |
| void CallLinkInfo::setStub(Ref<PolymorphicCallStubRoutine>&& newStub) |
| { |
| clearStub(); |
| m_stub = WTFMove(newStub); |
| |
| m_calleeOrCodeBlock.clear(); |
| |
| if (isDataIC()) { |
| *bitwise_cast<uintptr_t*>(m_calleeOrCodeBlock.slot()) = polymorphicCalleeMask; |
| u.dataIC.m_codeBlock = nullptr; // PolymorphicCallStubRoutine will set CodeBlock inside it. |
| u.dataIC.m_monomorphicCallDestination = m_stub->code().code().retagged<JSEntryPtrTag>(); |
| } else { |
| MacroAssembler::repatchPointer(u.codeIC.m_codeBlockLocation, nullptr); |
| MacroAssembler::replaceWithJump( |
| MacroAssembler::startOfBranchPtrWithPatchOnRegister(u.codeIC.m_calleeLocation), |
| CodeLocationLabel<JITStubRoutinePtrTag>(m_stub->code().code())); |
| } |
| } |
| |
| void CallLinkInfo::emitDataICSlowPath(VM&, CCallHelpers& jit, GPRReg callLinkInfoGPR) |
| { |
| jit.move(callLinkInfoGPR, GPRInfo::regT2); |
| jit.call(CCallHelpers::Address(GPRInfo::regT2, offsetOfSlowPathCallDestination()), JSEntryPtrTag); |
| } |
| |
| CCallHelpers::JumpList OptimizingCallLinkInfo::emitFastPath(CCallHelpers& jit, GPRReg calleeGPR, GPRReg callLinkInfoGPR) |
| { |
| RELEASE_ASSERT(!isTailCall()); |
| |
| if (isDataIC()) { |
| RELEASE_ASSERT(callLinkInfoGPR != GPRReg::InvalidGPRReg); |
| jit.move(CCallHelpers::TrustedImmPtr(this), callLinkInfoGPR); |
| setCallLinkInfoGPR(callLinkInfoGPR); |
| } |
| |
| return emitFastPathImpl(this, jit, calleeGPR, callLinkInfoGPR, useDataIC(), isTailCall(), nullptr); |
| } |
| |
| MacroAssembler::JumpList OptimizingCallLinkInfo::emitTailCallFastPath(CCallHelpers& jit, GPRReg calleeGPR, GPRReg callLinkInfoGPR, ScopedLambda<void()>&& prepareForTailCall) |
| { |
| RELEASE_ASSERT(isTailCall()); |
| |
| if (isDataIC()) { |
| RELEASE_ASSERT(callLinkInfoGPR != GPRReg::InvalidGPRReg); |
| jit.move(CCallHelpers::TrustedImmPtr(this), callLinkInfoGPR); |
| setCallLinkInfoGPR(callLinkInfoGPR); |
| } |
| |
| return emitFastPathImpl(this, jit, calleeGPR, callLinkInfoGPR, useDataIC(), isTailCall(), WTFMove(prepareForTailCall)); |
| } |
| |
| void OptimizingCallLinkInfo::emitSlowPath(VM& vm, CCallHelpers& jit) |
| { |
| setSlowPathCallDestination(vm.getCTILinkCall().code()); |
| jit.move(CCallHelpers::TrustedImmPtr(this), GPRInfo::regT2); |
| jit.call(CCallHelpers::Address(GPRInfo::regT2, offsetOfSlowPathCallDestination()), JSEntryPtrTag); |
| } |
| |
| CodeLocationLabel<JSInternalPtrTag> OptimizingCallLinkInfo::slowPathStart() |
| { |
| RELEASE_ASSERT(isDirect() && !isDataIC()); |
| return m_slowPathStart; |
| } |
| |
| CodeLocationLabel<JSInternalPtrTag> OptimizingCallLinkInfo::fastPathStart() |
| { |
| RELEASE_ASSERT(isDirect() && isTailCall()); |
| return CodeLocationDataLabelPtr<JSInternalPtrTag>(m_fastPathStart); |
| } |
| |
| void OptimizingCallLinkInfo::emitDirectFastPath(CCallHelpers& jit) |
| { |
| RELEASE_ASSERT(isDirect() && !isTailCall()); |
| |
| ASSERT(UseDataIC::No == this->useDataIC()); |
| |
| auto codeBlockStore = jit.storePtrWithPatch(CCallHelpers::TrustedImmPtr(nullptr), CCallHelpers::calleeFrameCodeBlockBeforeCall()); |
| auto call = jit.nearCall(); |
| jit.addLinkTask([=, this] (LinkBuffer& linkBuffer) { |
| m_callLocation = linkBuffer.locationOfNearCall<JSInternalPtrTag>(call); |
| u.codeIC.m_codeBlockLocation = linkBuffer.locationOf<JSInternalPtrTag>(codeBlockStore); |
| }); |
| jit.addLateLinkTask([this] (LinkBuffer&) { |
| initializeDirectCall(); |
| }); |
| } |
| |
| void OptimizingCallLinkInfo::emitDirectTailCallFastPath(CCallHelpers& jit, ScopedLambda<void()>&& prepareForTailCall) |
| { |
| RELEASE_ASSERT(isDirect() && isTailCall()); |
| |
| ASSERT(UseDataIC::No == this->useDataIC()); |
| |
| auto fastPathStart = jit.label(); |
| jit.addLinkTask([=, this] (LinkBuffer& linkBuffer) { |
| m_fastPathStart = linkBuffer.locationOf<JSInternalPtrTag>(fastPathStart); |
| }); |
| |
| // - If we're not yet linked, this is a jump to the slow path. |
| // - Once we're linked to a fast path, this goes back to being nops so we fall through to the linked jump. |
| jit.emitNops(CCallHelpers::patchableJumpSize()); |
| |
| prepareForTailCall(); |
| auto codeBlockStore = jit.storePtrWithPatch(CCallHelpers::TrustedImmPtr(nullptr), CCallHelpers::calleeFrameCodeBlockBeforeTailCall()); |
| auto call = jit.nearTailCall(); |
| jit.addLinkTask([=, this] (LinkBuffer& linkBuffer) { |
| m_callLocation = linkBuffer.locationOfNearCall<JSInternalPtrTag>(call); |
| u.codeIC.m_codeBlockLocation = linkBuffer.locationOf<JSInternalPtrTag>(codeBlockStore); |
| }); |
| jit.addLateLinkTask([this] (LinkBuffer&) { |
| initializeDirectCall(); |
| }); |
| } |
| |
| void OptimizingCallLinkInfo::initializeDirectCall() |
| { |
| RELEASE_ASSERT(isDirect()); |
| ASSERT(m_callLocation); |
| ASSERT(u.codeIC.m_codeBlockLocation); |
| if (isTailCall()) { |
| RELEASE_ASSERT(fastPathStart()); |
| CCallHelpers::emitJITCodeOver(fastPathStart(), scopedLambda<void(CCallHelpers&)>([&](CCallHelpers& jit) { |
| auto jump = jit.jump(); |
| jit.addLinkTask([=, this] (LinkBuffer& linkBuffer) { |
| linkBuffer.link(jump, slowPathStart()); |
| }); |
| }), "initialize direct call"); |
| } else |
| MacroAssembler::repatchNearCall(m_callLocation, slowPathStart()); |
| } |
| |
| void OptimizingCallLinkInfo::setDirectCallTarget(CodeBlock* codeBlock, CodeLocationLabel<JSEntryPtrTag> target) |
| { |
| RELEASE_ASSERT(isDirect()); |
| |
| if (isTailCall()) { |
| RELEASE_ASSERT(fastPathStart()); |
| CCallHelpers::emitJITCodeOver(fastPathStart(), scopedLambda<void(CCallHelpers&)>([&](CCallHelpers& jit) { |
| // We reserved this many bytes for the jump at fastPathStart(). Make that |
| // code nops now so we fall through to the jump to the fast path. |
| jit.emitNops(CCallHelpers::patchableJumpSize()); |
| }), "Setting direct call target"); |
| } |
| |
| MacroAssembler::repatchNearCall(m_callLocation, target); |
| MacroAssembler::repatchPointer(u.codeIC.m_codeBlockLocation, codeBlock); |
| } |
| |
| #endif |
| |
| } // namespace JSC |
