1 files changed, 136 insertions, 84 deletions

diff --git a/Source/JavaScriptCore/assembler/LinkBuffer.cpp b/Source/JavaScriptCore/assembler/LinkBuffer.cpp
index a7f469da8..0309d585d 100644
--- a/Source/JavaScriptCore/assembler/LinkBuffer.cpp
+++ b/Source/JavaScriptCore/assembler/LinkBuffer.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012, 2013 Apple Inc. All rights reserved.
+ * Copyright (C) 2012-2015 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -28,111 +28,164 @@
 
 #if ENABLE(ASSEMBLER)
 
+#include "CodeBlock.h"
+#include "JITCode.h"
+#include "JSCInlines.h"
 #include "Options.h"
 #include "VM.h"
 #include <wtf/CompilationThread.h>
 
 namespace JSC {
 
+bool shouldDumpDisassemblyFor(CodeBlock* codeBlock)
+{
+    if (codeBlock && JITCode::isOptimizingJIT(codeBlock->jitType()) && Options::dumpDFGDisassembly())
+        return true;
+    return Options::dumpDisassembly();
+}
+
 LinkBuffer::CodeRef LinkBuffer::finalizeCodeWithoutDisassembly()
 {
     performFinalization();
     
     ASSERT(m_didAllocate);
     if (m_executableMemory)
-        return CodeRef(m_executableMemory);
+        return CodeRef(*m_executableMemory);
     
     return CodeRef::createSelfManagedCodeRef(MacroAssemblerCodePtr(m_code));
 }
 
 LinkBuffer::CodeRef LinkBuffer::finalizeCodeWithDisassembly(const char* format, ...)
 {
-    ASSERT(Options::showDisassembly() || Options::showDFGDisassembly());
-    
     CodeRef result = finalizeCodeWithoutDisassembly();
 
-#if ENABLE(DISASSEMBLER)
-    dataLogF("Generated JIT code for ");
+    if (m_alreadyDisassembled)
+        return result;
+    
+    StringPrintStream out;
+    out.printf("Generated JIT code for ");
     va_list argList;
     va_start(argList, format);
-    WTF::dataLogFV(format, argList);
+    out.vprintf(format, argList);
     va_end(argList);
-    dataLogF(":\n");
+    out.printf(":\n");
+
+    out.printf("    Code at [%p, %p):\n", result.code().executableAddress(), static_cast<char*>(result.code().executableAddress()) + result.size());
+    
+    CString header = out.toCString();
+    
+    if (Options::asyncDisassembly()) {
+        disassembleAsynchronously(header, result, m_size, "    ");
+        return result;
+    }
     
-    dataLogF("    Code at [%p, %p):\n", result.code().executableAddress(), static_cast<char*>(result.code().executableAddress()) + result.size());
+    dataLog(header);
     disassemble(result.code(), m_size, "    ", WTF::dataFile());
-#else
-    UNUSED_PARAM(format);
-#endif // ENABLE(DISASSEMBLER)
     
     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(void* ownerUID, JITCompilationEffort effort)
+void LinkBuffer::copyCompactAndLinkCode(MacroAssembler& macroAssembler, void* ownerUID, JITCompilationEffort effort)
 {
-    m_initialSize = m_assembler->m_assembler.codeSize();
-    allocate(m_initialSize, ownerUID, effort);
-    uint8_t* inData = (uint8_t*)m_assembler->unlinkedCode();
-    uint8_t* outData = reinterpret_cast<uint8_t*>(m_code);
+    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());
+
+    AssemblerData outBuffer(m_size);
+
+    uint8_t* outData = reinterpret_cast<uint8_t*>(outBuffer.buffer());
+    uint8_t* codeOutData = 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);
+    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)
+                *copyDst++ = *copySource++;
+            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_DISABLED) {
+            for (unsigned i = 0; i < jumpCount; ++i)
+                ASSERT(!MacroAssembler::canCompact(jumpsToLink[i].type()));
         }
-        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);
+    memcpy(outData + writePtr, inData + readPtr, initialSize - readPtr);
+    recordLinkOffsets(m_assemblerStorage, readPtr, 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);
+        uint8_t* location = codeOutData + jumpsToLink[i].from();
+        uint8_t* target = codeOutData + jumpsToLink[i].to() - executableOffsetFor(jumpsToLink[i].to());
+        MacroAssembler::link(jumpsToLink[i], outData + jumpsToLink[i].from(), location, target);
     }
 
     jumpsToLink.clear();
-    shrink(writePtr + m_initialSize - readPtr);
+
+    size_t compactSize = writePtr + initialSize - readPtr;
+    if (m_executableMemory) {
+        m_size = compactSize;
+        m_executableMemory->shrink(m_size);
+    } else {
+        size_t nopSizeInBytes = initialSize - compactSize;
+        bool isCopyingToExecutableMemory = false;
+        MacroAssembler::AssemblerType_T::fillNops(outData + compactSize, nopSizeInBytes, isCopyingToExecutableMemory);
+    }
+
+    performJITMemcpy(m_code, outData, m_size);
 
 #if DUMP_LINK_STATISTICS
-    dumpLinkStatistics(m_code, m_initialSize, m_size);
+    dumpLinkStatistics(m_code, initialSize, m_size);
 #endif
 #if DUMP_CODE
     dumpCode(m_code, m_size);
@@ -141,59 +194,63 @@ void LinkBuffer::copyCompactAndLinkCode(void* ownerUID, JITCompilationEffort eff
 #endif
 
 
-void LinkBuffer::linkCode(void* ownerUID, JITCompilationEffort effort)
+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
-    m_assembler->m_assembler.buffer().flushConstantPool(false);
+    macroAssembler.m_assembler.buffer().flushConstantPool(false);
 #endif
-    AssemblerBuffer& buffer = m_assembler->m_assembler.buffer();
-    allocate(buffer.codeSize(), ownerUID, effort);
+    allocate(macroAssembler, ownerUID, effort);
     if (!m_didAllocate)
         return;
     ASSERT(m_code);
+    AssemblerBuffer& buffer = macroAssembler.m_assembler.buffer();
 #if CPU(ARM_TRADITIONAL)
-    m_assembler->m_assembler.prepareExecutableCopy(m_code);
+    macroAssembler.m_assembler.prepareExecutableCopy(m_code);
 #endif
-    memcpy(m_code, buffer.data(), buffer.codeSize());
+    performJITMemcpy(m_code, buffer.data(), buffer.codeSize());
 #if CPU(MIPS)
-    m_assembler->m_assembler.relocateJumps(buffer.data(), m_code);
+    macroAssembler.m_assembler.relocateJumps(buffer.data(), m_code);
 #endif
 #elif CPU(ARM_THUMB2)
-    copyCompactAndLinkCode<uint16_t>(ownerUID, effort);
+    copyCompactAndLinkCode<uint16_t>(macroAssembler, ownerUID, effort);
 #elif CPU(ARM64)
-    copyCompactAndLinkCode<uint32_t>(ownerUID, effort);
-#endif
+    copyCompactAndLinkCode<uint32_t>(macroAssembler, ownerUID, effort);
+#endif // !ENABLE(BRANCH_COMPACTION)
+
+    m_linkTasks = WTFMove(macroAssembler.m_linkTasks);
 }
 
-void LinkBuffer::allocate(size_t initialSize, void* ownerUID, JITCompilationEffort effort)
+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;
-        m_size = initialSize;
         return;
     }
     
+    ASSERT(m_vm != nullptr);
     m_executableMemory = m_vm->executableAllocator.allocate(*m_vm, initialSize, ownerUID, effort);
     if (!m_executableMemory)
         return;
-    ExecutableAllocator::makeWritable(m_executableMemory->start(), m_executableMemory->sizeInBytes());
     m_code = m_executableMemory->start();
     m_size = initialSize;
     m_didAllocate = true;
 }
 
-void LinkBuffer::shrink(size_t newSize)
-{
-    m_size = newSize;
-    m_executableMemory->shrink(m_size);
-}
-
 void LinkBuffer::performFinalization()
 {
+    for (auto& task : m_linkTasks)
+        task->run(*this);
+
 #ifndef NDEBUG
     ASSERT(!isCompilationThread());
     ASSERT(!m_completed);
@@ -201,11 +258,6 @@ void LinkBuffer::performFinalization()
     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);
 }