--- /dev/null
+/*
+ * Copyright (C) 2012 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 "Options.h"
+
+namespace JSC {
+
+LinkBuffer::CodeRef LinkBuffer::finalizeCodeWithoutDisassembly()
+{
+ performFinalization();
+
+ return CodeRef(m_executableMemory);
+}
+
+LinkBuffer::CodeRef LinkBuffer::finalizeCodeWithDisassembly(const char* format, ...)
+{
+ ASSERT(Options::showDisassembly() || Options::showDFGDisassembly());
+
+ CodeRef result = finalizeCodeWithoutDisassembly();
+
+ dataLogF("Generated JIT code for ");
+ va_list argList;
+ va_start(argList, format);
+ WTF::dataLogFV(format, argList);
+ va_end(argList);
+ dataLogF(":\n");
+
+ dataLogF(" Code at [%p, %p):\n", result.code().executableAddress(), static_cast<char*>(result.code().executableAddress()) + result.size());
+ disassemble(result.code(), m_size, " ", WTF::dataFile());
+
+ return result;
+}
+
+#if ENABLE(BRANCH_COMPACTION)
+template <typename InstructionType>
+void LinkBuffer::copyCompactAndLinkCode(void* ownerUID, JITCompilationEffort effort)
+{
+ m_initialSize = m_assembler->m_assembler.codeSize();
+ m_executableMemory = m_vm->executableAllocator.allocate(*m_vm, m_initialSize, ownerUID, effort);
+ if (!m_executableMemory)
+ return;
+ m_code = (uint8_t*)m_executableMemory->start();
+ ASSERT(m_code);
+ ExecutableAllocator::makeWritable(m_code, m_initialSize);
+ uint8_t* inData = (uint8_t*)m_assembler->unlinkedCode();
+ uint8_t* outData = reinterpret_cast<uint8_t*>(m_code);
+ int readPtr = 0;
+ int writePtr = 0;
+ Vector<LinkRecord, 0, UnsafeVectorOverflow>& jumpsToLink = m_assembler->jumpsToLink();
+ unsigned jumpCount = jumpsToLink.size();
+ 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)
+ *copyDst++ = *copySource++;
+ m_assembler->recordLinkOffsets(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 = outData + jumpsToLink[i].to() - offset; // Compensate for what we have collapsed so far
+ else
+ target = outData + jumpsToLink[i].to() - m_assembler->executableOffsetFor(jumpsToLink[i].to());
+
+ JumpLinkType jumpLinkType = m_assembler->computeJumpType(jumpsToLink[i], outData + writePtr, target);
+ // Compact branch if we can...
+ if (m_assembler->canCompact(jumpsToLink[i].type())) {
+ // Step back in the write stream
+ int32_t delta = m_assembler->jumpSizeDelta(jumpsToLink[i].type(), jumpLinkType);
+ if (delta) {
+ writePtr -= delta;
+ m_assembler->recordLinkOffsets(jumpsToLink[i].from() - delta, readPtr, readPtr - writePtr);
+ }
+ }
+ jumpsToLink[i].setFrom(writePtr);
+ }
+ // Copy everything after the last jump
+ memcpy(outData + writePtr, inData + readPtr, m_initialSize - readPtr);
+ m_assembler->recordLinkOffsets(readPtr, m_initialSize, readPtr - writePtr);
+
+ for (unsigned i = 0; i < jumpCount; ++i) {
+ uint8_t* location = outData + jumpsToLink[i].from();
+ uint8_t* target = outData + jumpsToLink[i].to() - m_assembler->executableOffsetFor(jumpsToLink[i].to());
+ m_assembler->link(jumpsToLink[i], location, target);
+ }
+
+ jumpsToLink.clear();
+ m_size = writePtr + m_initialSize - readPtr;
+ m_executableMemory->shrink(m_size);
+
+#if DUMP_LINK_STATISTICS
+ dumpLinkStatistics(m_code, m_initialSize, m_size);
+#endif
+#if DUMP_CODE
+ dumpCode(m_code, m_size);
+#endif
+}
+#endif
+
+
+void LinkBuffer::linkCode(void* ownerUID, JITCompilationEffort effort)
+{
+ ASSERT(!m_code);
+#if !ENABLE(BRANCH_COMPACTION)
+ m_executableMemory = m_assembler->m_assembler.executableCopy(*m_vm, ownerUID, effort);
+ if (!m_executableMemory)
+ return;
+ m_code = m_executableMemory->start();
+ m_size = m_assembler->m_assembler.codeSize();
+ ASSERT(m_code);
+#elif CPU(ARM_THUMB2)
+ copyCompactAndLinkCode<uint16_t>(ownerUID, effort);
+#elif CPU(ARM64)
+ copyCompactAndLinkCode<uint32_t>(ownerUID, effort);
+#endif
+}
+
+void LinkBuffer::performFinalization()
+{
+#ifndef NDEBUG
+ ASSERT(!m_completed);
+ ASSERT(isValid());
+ m_completed = true;
+#endif
+
+#if ENABLE(BRANCH_COMPACTION)
+ ExecutableAllocator::makeExecutable(code(), m_initialSize);
+#else
+ ExecutableAllocator::makeExecutable(code(), m_size);
+#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]);
+#elif CPU(ARM_TRADITIONAL)
+ // gcc -c jit.s
+ // objdump -D jit.o
+ static unsigned codeCount = 0;
+ unsigned int* tcode = static_cast<unsigned int*>(code);
+ size_t tsize = size / sizeof(unsigned int);
+ char nameBuf[128];
+ snprintf(nameBuf, sizeof(nameBuf), "_jsc_jit%u", codeCount++);
+ dataLogF("\t.globl\t%s\n"
+ "\t.align 4\n"
+ "\t.code 32\n"
+ "\t.text\n"
+ "# %p\n"
+ "%s:\n", nameBuf, code, nameBuf);
+
+ for (unsigned i = 0; i < tsize; i++)
+ dataLogF("\t.long\t0x%x\n", tcode[i]);
+#endif
+}
+#endif
+
+} // namespace JSC
+
+#endif // ENABLE(ASSEMBLER)
+
+
projects / apple / javascriptcore.git / blobdiff