| /* |
| * Copyright (C) 2012-2019 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 "LinkBuffer.h" |
| |
| #if ENABLE(ASSEMBLER) |
| |
| #include "CodeBlock.h" |
| #include "Disassembler.h" |
| #include "JITCode.h" |
| #include "JSCInlines.h" |
| #include "Options.h" |
| #include "WasmCompilationMode.h" |
| #include <wtf/CompilationThread.h> |
| |
| #if OS(LINUX) |
| #include "PerfLog.h" |
| #endif |
| |
| namespace JSC { |
| |
| bool shouldDumpDisassemblyFor(CodeBlock* codeBlock) |
| { |
| if (codeBlock && JITCode::isOptimizingJIT(codeBlock->jitType()) && Options::dumpDFGDisassembly()) |
| return true; |
| return Options::dumpDisassembly(); |
| } |
| |
| bool shouldDumpDisassemblyFor(Wasm::CompilationMode mode) |
| { |
| if (Options::asyncDisassembly() || Options::dumpDisassembly() || Options::dumpWasmDisassembly()) |
| return true; |
| switch (mode) { |
| case Wasm::CompilationMode::BBQMode: |
| return Options::dumpBBQDisassembly(); |
| case Wasm::CompilationMode::OMGMode: |
| case Wasm::CompilationMode::OMGForOSREntryMode: |
| return Options::dumpOMGDisassembly(); |
| default: |
| break; |
| } |
| return false; |
| } |
| |
| LinkBuffer::CodeRef<LinkBufferPtrTag> LinkBuffer::finalizeCodeWithoutDisassemblyImpl() |
| { |
| performFinalization(); |
| |
| ASSERT(m_didAllocate); |
| if (m_executableMemory) |
| return CodeRef<LinkBufferPtrTag>(*m_executableMemory); |
| |
| return CodeRef<LinkBufferPtrTag>::createSelfManagedCodeRef(m_code); |
| } |
| |
| LinkBuffer::CodeRef<LinkBufferPtrTag> LinkBuffer::finalizeCodeWithDisassemblyImpl(bool dumpDisassembly, const char* format, ...) |
| { |
| CodeRef<LinkBufferPtrTag> result = finalizeCodeWithoutDisassemblyImpl(); |
| |
| #if OS(LINUX) |
| if (Options::logJITCodeForPerf()) { |
| StringPrintStream out; |
| va_list argList; |
| va_start(argList, format); |
| va_start(argList, format); |
| out.vprintf(format, argList); |
| va_end(argList); |
| PerfLog::log(out.toCString(), result.code().untaggedExecutableAddress<const uint8_t*>(), result.size()); |
| } |
| #endif |
| |
| if (!dumpDisassembly || m_alreadyDisassembled) |
| return result; |
| |
| StringPrintStream out; |
| out.printf("Generated JIT code for "); |
| va_list argList; |
| va_start(argList, format); |
| out.vprintf(format, argList); |
| va_end(argList); |
| out.printf(":\n"); |
| |
| uint8_t* executableAddress = result.code().untaggedExecutableAddress<uint8_t*>(); |
| out.printf(" Code at [%p, %p):\n", executableAddress, executableAddress + result.size()); |
| |
| CString header = out.toCString(); |
| |
| if (Options::asyncDisassembly()) { |
| CodeRef<DisassemblyPtrTag> codeRefForDisassembly = result.retagged<DisassemblyPtrTag>(); |
| disassembleAsynchronously(header, WTFMove(codeRefForDisassembly), m_size, " "); |
| return result; |
| } |
| |
| dataLog(header); |
| disassemble(result.retaggedCode<DisassemblyPtrTag>(), m_size, " ", WTF::dataFile()); |
| |
| return result; |
| } |
| |
| #if ENABLE(BRANCH_COMPACTION) |
| static ALWAYS_INLINE void recordLinkOffsets(AssemblerData& assemblerData, int32_t regionStart, int32_t regionEnd, int32_t offset) |
| { |
| int32_t ptr = regionStart / sizeof(int32_t); |
| const int32_t end = regionEnd / sizeof(int32_t); |
| int32_t* offsets = reinterpret_cast_ptr<int32_t*>(assemblerData.buffer()); |
| while (ptr < end) |
| offsets[ptr++] = offset; |
| } |
| |
| template <typename InstructionType> |
| void LinkBuffer::copyCompactAndLinkCode(MacroAssembler& macroAssembler, void* ownerUID, JITCompilationEffort effort) |
| { |
| allocate(macroAssembler, ownerUID, effort); |
| const size_t initialSize = macroAssembler.m_assembler.codeSize(); |
| if (didFailToAllocate()) |
| return; |
| |
| Vector<LinkRecord, 0, UnsafeVectorOverflow>& jumpsToLink = macroAssembler.jumpsToLink(); |
| m_assemblerStorage = macroAssembler.m_assembler.buffer().releaseAssemblerData(); |
| uint8_t* inData = reinterpret_cast<uint8_t*>(m_assemblerStorage.buffer()); |
| |
| uint8_t* codeOutData = m_code.dataLocation<uint8_t*>(); |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| const uint32_t expectedFinalHash = macroAssembler.m_assembler.buffer().hash().finalHash(); |
| ARM64EHash verifyUncompactedHash; |
| uint8_t* outData = codeOutData; |
| #else |
| AssemblerData outBuffer(m_size); |
| uint8_t* outData = reinterpret_cast<uint8_t*>(outBuffer.buffer()); |
| #endif |
| #if CPU(ARM64) |
| RELEASE_ASSERT(roundUpToMultipleOf<sizeof(unsigned)>(outData) == outData); |
| RELEASE_ASSERT(roundUpToMultipleOf<sizeof(unsigned)>(codeOutData) == codeOutData); |
| #endif |
| |
| int readPtr = 0; |
| int writePtr = 0; |
| unsigned jumpCount = jumpsToLink.size(); |
| |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| os_thread_self_restrict_rwx_to_rw(); |
| #endif |
| |
| if (m_shouldPerformBranchCompaction) { |
| for (unsigned i = 0; i < jumpCount; ++i) { |
| int offset = readPtr - writePtr; |
| ASSERT(!(offset & 1)); |
| |
| // Copy the instructions from the last jump to the current one. |
| size_t regionSize = jumpsToLink[i].from() - readPtr; |
| InstructionType* copySource = reinterpret_cast_ptr<InstructionType*>(inData + readPtr); |
| InstructionType* copyEnd = reinterpret_cast_ptr<InstructionType*>(inData + readPtr + regionSize); |
| InstructionType* copyDst = reinterpret_cast_ptr<InstructionType*>(outData + writePtr); |
| ASSERT(!(regionSize % 2)); |
| ASSERT(!(readPtr % 2)); |
| ASSERT(!(writePtr % 2)); |
| while (copySource != copyEnd) { |
| InstructionType insn = *copySource++; |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| static_assert(sizeof(InstructionType) == 4, ""); |
| verifyUncompactedHash.update(insn); |
| #endif |
| *copyDst++ = insn; |
| } |
| recordLinkOffsets(m_assemblerStorage, readPtr, jumpsToLink[i].from(), offset); |
| readPtr += regionSize; |
| writePtr += regionSize; |
| |
| // Calculate absolute address of the jump target, in the case of backwards |
| // branches we need to be precise, forward branches we are pessimistic |
| const uint8_t* target; |
| if (jumpsToLink[i].to() >= jumpsToLink[i].from()) |
| target = codeOutData + jumpsToLink[i].to() - offset; // Compensate for what we have collapsed so far |
| else |
| target = codeOutData + jumpsToLink[i].to() - executableOffsetFor(jumpsToLink[i].to()); |
| |
| JumpLinkType jumpLinkType = MacroAssembler::computeJumpType(jumpsToLink[i], codeOutData + writePtr, target); |
| // Compact branch if we can... |
| if (MacroAssembler::canCompact(jumpsToLink[i].type())) { |
| // Step back in the write stream |
| int32_t delta = MacroAssembler::jumpSizeDelta(jumpsToLink[i].type(), jumpLinkType); |
| if (delta) { |
| writePtr -= delta; |
| recordLinkOffsets(m_assemblerStorage, jumpsToLink[i].from() - delta, readPtr, readPtr - writePtr); |
| } |
| } |
| jumpsToLink[i].setFrom(writePtr); |
| } |
| } else { |
| if (ASSERT_ENABLED) { |
| for (unsigned i = 0; i < jumpCount; ++i) |
| ASSERT(!MacroAssembler::canCompact(jumpsToLink[i].type())); |
| } |
| } |
| |
| // Copy everything after the last jump |
| { |
| InstructionType* dst = bitwise_cast<InstructionType*>(outData + writePtr); |
| InstructionType* src = bitwise_cast<InstructionType*>(inData + readPtr); |
| size_t bytes = initialSize - readPtr; |
| |
| RELEASE_ASSERT(bitwise_cast<uintptr_t>(dst) % sizeof(InstructionType) == 0); |
| RELEASE_ASSERT(bitwise_cast<uintptr_t>(src) % sizeof(InstructionType) == 0); |
| RELEASE_ASSERT(bytes % sizeof(InstructionType) == 0); |
| |
| for (size_t i = 0; i < bytes; i += sizeof(InstructionType)) { |
| InstructionType insn = *src++; |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| verifyUncompactedHash.update(insn); |
| #endif |
| *dst++ = insn; |
| } |
| } |
| |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| if (verifyUncompactedHash.finalHash() != expectedFinalHash) { |
| dataLogLn("Hashes don't match: ", RawPointer(bitwise_cast<void*>(static_cast<uintptr_t>(verifyUncompactedHash.finalHash()))), " ", RawPointer(bitwise_cast<void*>(static_cast<uintptr_t>(expectedFinalHash)))); |
| dataLogLn("Crashing!"); |
| CRASH(); |
| } |
| #endif |
| |
| recordLinkOffsets(m_assemblerStorage, readPtr, initialSize, readPtr - writePtr); |
| |
| for (unsigned i = 0; i < jumpCount; ++i) { |
| uint8_t* location = codeOutData + jumpsToLink[i].from(); |
| uint8_t* target = codeOutData + jumpsToLink[i].to() - executableOffsetFor(jumpsToLink[i].to()); |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| MacroAssembler::link<memcpy>(jumpsToLink[i], outData + jumpsToLink[i].from(), location, target); |
| #else |
| MacroAssembler::link<performJITMemcpy>(jumpsToLink[i], outData + jumpsToLink[i].from(), location, target); |
| #endif |
| } |
| |
| size_t compactSize = writePtr + initialSize - readPtr; |
| if (!m_executableMemory) { |
| size_t nopSizeInBytes = initialSize - compactSize; |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| Assembler::fillNops<memcpy>(outData + compactSize, nopSizeInBytes); |
| #else |
| Assembler::fillNops<performJITMemcpy>(outData + compactSize, nopSizeInBytes); |
| #endif |
| } |
| |
| #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS) |
| os_thread_self_restrict_rwx_to_rx(); |
| #endif |
| |
| if (m_executableMemory) { |
| m_size = compactSize; |
| m_executableMemory->shrink(m_size); |
| } |
| |
| #if !CPU(ARM64E) || !ENABLE(FAST_JIT_PERMISSIONS) |
| ASSERT(codeOutData != outData); |
| performJITMemcpy(codeOutData, outData, m_size); |
| #else |
| ASSERT(codeOutData == outData); |
| if (UNLIKELY(Options::dumpJITMemoryPath())) |
| dumpJITMemory(outData, outData, m_size); |
| #endif |
| |
| jumpsToLink.clear(); |
| |
| #if DUMP_LINK_STATISTICS |
| dumpLinkStatistics(codeOutData, initialSize, m_size); |
| #endif |
| #if DUMP_CODE |
| dumpCode(codeOutData, m_size); |
| #endif |
| } |
| #endif // ENABLE(BRANCH_COMPACTION) |
| |
| |
| void LinkBuffer::linkCode(MacroAssembler& macroAssembler, void* ownerUID, JITCompilationEffort effort) |
| { |
| // Ensure that the end of the last invalidation point does not extend beyond the end of the buffer. |
| macroAssembler.label(); |
| |
| #if !ENABLE(BRANCH_COMPACTION) |
| #if defined(ASSEMBLER_HAS_CONSTANT_POOL) && ASSEMBLER_HAS_CONSTANT_POOL |
| macroAssembler.m_assembler.buffer().flushConstantPool(false); |
| #endif |
| allocate(macroAssembler, ownerUID, effort); |
| if (!m_didAllocate) |
| return; |
| ASSERT(m_code); |
| AssemblerBuffer& buffer = macroAssembler.m_assembler.buffer(); |
| void* code = m_code.dataLocation(); |
| #if CPU(ARM64) |
| RELEASE_ASSERT(roundUpToMultipleOf<Assembler::instructionSize>(code) == code); |
| #endif |
| performJITMemcpy(code, buffer.data(), buffer.codeSize()); |
| #if CPU(MIPS) |
| macroAssembler.m_assembler.relocateJumps(buffer.data(), code); |
| #endif |
| #elif CPU(ARM_THUMB2) |
| copyCompactAndLinkCode<uint16_t>(macroAssembler, ownerUID, effort); |
| #elif CPU(ARM64) |
| copyCompactAndLinkCode<uint32_t>(macroAssembler, ownerUID, effort); |
| #endif // !ENABLE(BRANCH_COMPACTION) |
| |
| m_linkTasks = WTFMove(macroAssembler.m_linkTasks); |
| } |
| |
| void LinkBuffer::allocate(MacroAssembler& macroAssembler, void* ownerUID, JITCompilationEffort effort) |
| { |
| size_t initialSize = macroAssembler.m_assembler.codeSize(); |
| if (m_code) { |
| if (initialSize > m_size) |
| return; |
| |
| size_t nopsToFillInBytes = m_size - initialSize; |
| macroAssembler.emitNops(nopsToFillInBytes); |
| m_didAllocate = true; |
| return; |
| } |
| |
| while (initialSize % jitAllocationGranule) { |
| macroAssembler.breakpoint(); |
| initialSize = macroAssembler.m_assembler.codeSize(); |
| } |
| |
| m_executableMemory = ExecutableAllocator::singleton().allocate(initialSize, ownerUID, effort); |
| if (!m_executableMemory) |
| return; |
| m_code = MacroAssemblerCodePtr<LinkBufferPtrTag>(m_executableMemory->start().retaggedPtr<LinkBufferPtrTag>()); |
| m_size = initialSize; |
| m_didAllocate = true; |
| } |
| |
| void LinkBuffer::performFinalization() |
| { |
| for (auto& task : m_linkTasks) |
| task->run(*this); |
| |
| #ifndef NDEBUG |
| ASSERT(!isCompilationThread()); |
| ASSERT(!m_completed); |
| ASSERT(isValid()); |
| m_completed = true; |
| #endif |
| |
| MacroAssembler::cacheFlush(code(), m_size); |
| } |
| |
| #if DUMP_LINK_STATISTICS |
| void LinkBuffer::dumpLinkStatistics(void* code, size_t initializeSize, size_t finalSize) |
| { |
| static unsigned linkCount = 0; |
| static unsigned totalInitialSize = 0; |
| static unsigned totalFinalSize = 0; |
| linkCount++; |
| totalInitialSize += initialSize; |
| totalFinalSize += finalSize; |
| dataLogF("link %p: orig %u, compact %u (delta %u, %.2f%%)\n", |
| code, static_cast<unsigned>(initialSize), static_cast<unsigned>(finalSize), |
| static_cast<unsigned>(initialSize - finalSize), |
| 100.0 * (initialSize - finalSize) / initialSize); |
| dataLogF("\ttotal %u: orig %u, compact %u (delta %u, %.2f%%)\n", |
| linkCount, totalInitialSize, totalFinalSize, totalInitialSize - totalFinalSize, |
| 100.0 * (totalInitialSize - totalFinalSize) / totalInitialSize); |
| } |
| #endif |
| |
| #if DUMP_CODE |
| void LinkBuffer::dumpCode(void* code, size_t size) |
| { |
| #if CPU(ARM_THUMB2) |
| // Dump the generated code in an asm file format that can be assembled and then disassembled |
| // for debugging purposes. For example, save this output as jit.s: |
| // gcc -arch armv7 -c jit.s |
| // otool -tv jit.o |
| static unsigned codeCount = 0; |
| unsigned short* tcode = static_cast<unsigned short*>(code); |
| size_t tsize = size / sizeof(short); |
| char nameBuf[128]; |
| snprintf(nameBuf, sizeof(nameBuf), "_jsc_jit%u", codeCount++); |
| dataLogF("\t.syntax unified\n" |
| "\t.section\t__TEXT,__text,regular,pure_instructions\n" |
| "\t.globl\t%s\n" |
| "\t.align 2\n" |
| "\t.code 16\n" |
| "\t.thumb_func\t%s\n" |
| "# %p\n" |
| "%s:\n", nameBuf, nameBuf, code, nameBuf); |
| |
| for (unsigned i = 0; i < tsize; i++) |
| dataLogF("\t.short\t0x%x\n", tcode[i]); |
| #endif |
| } |
| #endif |
| |
| } // namespace JSC |
| |
| #endif // ENABLE(ASSEMBLER) |
