webkitgtk-2.10.2webkitgtk-2.10.2

1 files changed, 778 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/jit/JIT.cpp b/Source/JavaScriptCore/jit/JIT.cpp
new file mode 100644
index 000000000..038f5d7db
--- /dev/null
+++ b/Source/JavaScriptCore/jit/JIT.cpp
@@ -0,0 +1,778 @@
+/*
+ * Copyright (C) 2008, 2009, 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
+ * 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"
+
+#if ENABLE(JIT)
+
+#include "JIT.h"
+
+#include "ArityCheckFailReturnThunks.h"
+#include "CodeBlock.h"
+#include "CodeBlockWithJITType.h"
+#include "DFGCapabilities.h"
+#include "Interpreter.h"
+#include "JITInlines.h"
+#include "JITOperations.h"
+#include "JSArray.h"
+#include "JSFunction.h"
+#include "LinkBuffer.h"
+#include "MaxFrameExtentForSlowPathCall.h"
+#include "JSCInlines.h"
+#include "ProfilerDatabase.h"
+#include "RepatchBuffer.h"
+#include "ResultType.h"
+#include "SamplingTool.h"
+#include "SlowPathCall.h"
+#include "StackAlignment.h"
+#include "TypeProfilerLog.h"
+#include <wtf/CryptographicallyRandomNumber.h>
+
+using namespace std;
+
+namespace JSC {
+
+void ctiPatchNearCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction)
+{
+    RepatchBuffer repatchBuffer(codeblock);
+    repatchBuffer.relinkNearCallerToTrampoline(returnAddress, newCalleeFunction);
+}
+
+void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction)
+{
+    RepatchBuffer repatchBuffer(codeblock);
+    repatchBuffer.relinkCallerToTrampoline(returnAddress, newCalleeFunction);
+}
+
+void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, FunctionPtr newCalleeFunction)
+{
+    RepatchBuffer repatchBuffer(codeblock);
+    repatchBuffer.relinkCallerToFunction(returnAddress, newCalleeFunction);
+}
+
+JIT::JIT(VM* vm, CodeBlock* codeBlock)
+    : JSInterfaceJIT(vm, codeBlock)
+    , m_interpreter(vm->interpreter)
+    , m_labels(codeBlock ? codeBlock->numberOfInstructions() : 0)
+    , m_bytecodeOffset(std::numeric_limits<unsigned>::max())
+    , m_getByIdIndex(UINT_MAX)
+    , m_putByIdIndex(UINT_MAX)
+    , m_byValInstructionIndex(UINT_MAX)
+    , m_callLinkInfoIndex(UINT_MAX)
+    , m_randomGenerator(cryptographicallyRandomNumber())
+    , m_canBeOptimized(false)
+    , m_shouldEmitProfiling(false)
+{
+}
+
+#if ENABLE(DFG_JIT)
+void JIT::emitEnterOptimizationCheck()
+{
+    if (!canBeOptimized())
+        return;
+
+    JumpList skipOptimize;
+    
+    skipOptimize.append(branchAdd32(Signed, TrustedImm32(Options::executionCounterIncrementForEntry()), AbsoluteAddress(m_codeBlock->addressOfJITExecuteCounter())));
+    ASSERT(!m_bytecodeOffset);
+    callOperation(operationOptimize, m_bytecodeOffset);
+    skipOptimize.append(branchTestPtr(Zero, returnValueGPR));
+    move(returnValueGPR2, stackPointerRegister);
+    jump(returnValueGPR);
+    skipOptimize.link(this);
+}
+#endif
+
+void JIT::emitNotifyWrite(WatchpointSet* set)
+{
+    if (!set || set->state() == IsInvalidated)
+        return;
+    
+    addSlowCase(branch8(NotEqual, AbsoluteAddress(set->addressOfState()), TrustedImm32(IsInvalidated)));
+}
+
+void JIT::assertStackPointerOffset()
+{
+    if (ASSERT_DISABLED)
+        return;
+    
+    addPtr(TrustedImm32(stackPointerOffsetFor(m_codeBlock) * sizeof(Register)), callFrameRegister, regT0);
+    Jump ok = branchPtr(Equal, regT0, stackPointerRegister);
+    breakpoint();
+    ok.link(this);
+}
+
+#define NEXT_OPCODE(name) \
+    m_bytecodeOffset += OPCODE_LENGTH(name); \
+    break;
+
+#define DEFINE_SLOW_OP(name) \
+    case op_##name: { \
+        JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_##name); \
+        slowPathCall.call(); \
+        NEXT_OPCODE(op_##name); \
+    }
+
+#define DEFINE_OP(name) \
+    case name: { \
+        emit_##name(currentInstruction); \
+        NEXT_OPCODE(name); \
+    }
+
+#define DEFINE_SLOWCASE_OP(name) \
+    case name: { \
+        emitSlow_##name(currentInstruction, iter); \
+        NEXT_OPCODE(name); \
+    }
+
+void JIT::privateCompileMainPass()
+{
+    jitAssertTagsInPlace();
+    jitAssertArgumentCountSane();
+    
+    Instruction* instructionsBegin = m_codeBlock->instructions().begin();
+    unsigned instructionCount = m_codeBlock->instructions().size();
+
+    m_callLinkInfoIndex = 0;
+
+    for (m_bytecodeOffset = 0; m_bytecodeOffset < instructionCount; ) {
+        if (m_disassembler)
+            m_disassembler->setForBytecodeMainPath(m_bytecodeOffset, label());
+        Instruction* currentInstruction = instructionsBegin + m_bytecodeOffset;
+        ASSERT_WITH_MESSAGE(m_interpreter->isOpcode(currentInstruction->u.opcode), "privateCompileMainPass gone bad @ %d", m_bytecodeOffset);
+
+#if ENABLE(OPCODE_SAMPLING)
+        if (m_bytecodeOffset > 0) // Avoid the overhead of sampling op_enter twice.
+            sampleInstruction(currentInstruction);
+#endif
+
+        m_labels[m_bytecodeOffset] = label();
+
+#if ENABLE(JIT_VERBOSE)
+        dataLogF("Old JIT emitting code for bc#%u at offset 0x%lx.\n", m_bytecodeOffset, (long)debugOffset());
+#endif
+        
+        OpcodeID opcodeID = m_interpreter->getOpcodeID(currentInstruction->u.opcode);
+
+        if (m_compilation) {
+            add64(
+                TrustedImm32(1),
+                AbsoluteAddress(m_compilation->executionCounterFor(Profiler::OriginStack(Profiler::Origin(
+                    m_compilation->bytecodes(), m_bytecodeOffset)))->address()));
+        }
+        
+        if (Options::eagerlyUpdateTopCallFrame())
+            updateTopCallFrame();
+        
+        switch (opcodeID) {
+        DEFINE_SLOW_OP(del_by_val)
+        DEFINE_SLOW_OP(in)
+        DEFINE_SLOW_OP(less)
+        DEFINE_SLOW_OP(lesseq)
+        DEFINE_SLOW_OP(greater)
+        DEFINE_SLOW_OP(greatereq)
+        DEFINE_SLOW_OP(is_function)
+        DEFINE_SLOW_OP(is_object_or_null)
+        DEFINE_SLOW_OP(typeof)
+
+        DEFINE_OP(op_add)
+        DEFINE_OP(op_bitand)
+        DEFINE_OP(op_bitor)
+        DEFINE_OP(op_bitxor)
+        DEFINE_OP(op_call)
+        DEFINE_OP(op_call_eval)
+        DEFINE_OP(op_call_varargs)
+        DEFINE_OP(op_construct_varargs)
+        DEFINE_OP(op_catch)
+        DEFINE_OP(op_construct)
+        DEFINE_OP(op_create_this)
+        DEFINE_OP(op_to_this)
+        DEFINE_OP(op_create_direct_arguments)
+        DEFINE_OP(op_create_scoped_arguments)
+        DEFINE_OP(op_create_out_of_band_arguments)
+        DEFINE_OP(op_check_tdz)
+        DEFINE_OP(op_debug)
+        DEFINE_OP(op_del_by_id)
+        DEFINE_OP(op_div)
+        DEFINE_OP(op_end)
+        DEFINE_OP(op_enter)
+        DEFINE_OP(op_get_scope)
+        DEFINE_OP(op_eq)
+        DEFINE_OP(op_eq_null)
+        case op_get_by_id_out_of_line:
+        case op_get_array_length:
+        DEFINE_OP(op_get_by_id)
+        DEFINE_OP(op_get_by_val)
+        DEFINE_OP(op_check_has_instance)
+        DEFINE_OP(op_instanceof)
+        DEFINE_OP(op_is_undefined)
+        DEFINE_OP(op_is_boolean)
+        DEFINE_OP(op_is_number)
+        DEFINE_OP(op_is_string)
+        DEFINE_OP(op_is_object)
+        DEFINE_OP(op_jeq_null)
+        DEFINE_OP(op_jfalse)
+        DEFINE_OP(op_jmp)
+        DEFINE_OP(op_jneq_null)
+        DEFINE_OP(op_jneq_ptr)
+        DEFINE_OP(op_jless)
+        DEFINE_OP(op_jlesseq)
+        DEFINE_OP(op_jgreater)
+        DEFINE_OP(op_jgreatereq)
+        DEFINE_OP(op_jnless)
+        DEFINE_OP(op_jnlesseq)
+        DEFINE_OP(op_jngreater)
+        DEFINE_OP(op_jngreatereq)
+        DEFINE_OP(op_jtrue)
+        DEFINE_OP(op_loop_hint)
+        DEFINE_OP(op_lshift)
+        DEFINE_OP(op_mod)
+        DEFINE_OP(op_mov)
+        DEFINE_OP(op_mul)
+        DEFINE_OP(op_negate)
+        DEFINE_OP(op_neq)
+        DEFINE_OP(op_neq_null)
+        DEFINE_OP(op_new_array)
+        DEFINE_OP(op_new_array_with_size)
+        DEFINE_OP(op_new_array_buffer)
+        DEFINE_OP(op_new_func)
+        DEFINE_OP(op_new_func_exp)
+        DEFINE_OP(op_new_object)
+        DEFINE_OP(op_new_regexp)
+        DEFINE_OP(op_not)
+        DEFINE_OP(op_nstricteq)
+        DEFINE_OP(op_dec)
+        DEFINE_OP(op_inc)
+        DEFINE_OP(op_profile_did_call)
+        DEFINE_OP(op_profile_will_call)
+        DEFINE_OP(op_profile_type)
+        DEFINE_OP(op_profile_control_flow)
+        DEFINE_OP(op_push_with_scope)
+        DEFINE_OP(op_create_lexical_environment)
+        DEFINE_OP(op_get_parent_scope)
+        case op_put_by_id_out_of_line:
+        case op_put_by_id_transition_direct:
+        case op_put_by_id_transition_normal:
+        case op_put_by_id_transition_direct_out_of_line:
+        case op_put_by_id_transition_normal_out_of_line:
+        DEFINE_OP(op_put_by_id)
+        DEFINE_OP(op_put_by_index)
+        case op_put_by_val_direct:
+        DEFINE_OP(op_put_by_val)
+        DEFINE_OP(op_put_getter_by_id)
+        DEFINE_OP(op_put_setter_by_id)
+        DEFINE_OP(op_put_getter_setter)
+
+        DEFINE_OP(op_ret)
+        DEFINE_OP(op_rshift)
+        DEFINE_OP(op_unsigned)
+        DEFINE_OP(op_urshift)
+        DEFINE_OP(op_strcat)
+        DEFINE_OP(op_stricteq)
+        DEFINE_OP(op_sub)
+        DEFINE_OP(op_switch_char)
+        DEFINE_OP(op_switch_imm)
+        DEFINE_OP(op_switch_string)
+        DEFINE_OP(op_throw)
+        DEFINE_OP(op_throw_static_error)
+        DEFINE_OP(op_to_number)
+        DEFINE_OP(op_to_string)
+        DEFINE_OP(op_to_primitive)
+
+        DEFINE_OP(op_resolve_scope)
+        DEFINE_OP(op_get_from_scope)
+        DEFINE_OP(op_put_to_scope)
+        DEFINE_OP(op_get_from_arguments)
+        DEFINE_OP(op_put_to_arguments)
+
+        DEFINE_OP(op_get_enumerable_length)
+        DEFINE_OP(op_has_generic_property)
+        DEFINE_OP(op_has_structure_property)
+        DEFINE_OP(op_has_indexed_property)
+        DEFINE_OP(op_get_direct_pname)
+        DEFINE_OP(op_get_property_enumerator)
+        DEFINE_OP(op_enumerator_structure_pname)
+        DEFINE_OP(op_enumerator_generic_pname)
+        DEFINE_OP(op_to_index_string)
+        default:
+            RELEASE_ASSERT_NOT_REACHED();
+        }
+    }
+
+    RELEASE_ASSERT(m_callLinkInfoIndex == m_callCompilationInfo.size());
+
+#ifndef NDEBUG
+    // Reset this, in order to guard its use with ASSERTs.
+    m_bytecodeOffset = std::numeric_limits<unsigned>::max();
+#endif
+}
+
+void JIT::privateCompileLinkPass()
+{
+    unsigned jmpTableCount = m_jmpTable.size();
+    for (unsigned i = 0; i < jmpTableCount; ++i)
+        m_jmpTable[i].from.linkTo(m_labels[m_jmpTable[i].toBytecodeOffset], this);
+    m_jmpTable.clear();
+}
+
+void JIT::privateCompileSlowCases()
+{
+    Instruction* instructionsBegin = m_codeBlock->instructions().begin();
+
+    m_getByIdIndex = 0;
+    m_putByIdIndex = 0;
+    m_byValInstructionIndex = 0;
+    m_callLinkInfoIndex = 0;
+    
+    // Use this to assert that slow-path code associates new profiling sites with existing
+    // ValueProfiles rather than creating new ones. This ensures that for a given instruction
+    // (say, get_by_id) we get combined statistics for both the fast-path executions of that
+    // instructions and the slow-path executions. Furthermore, if the slow-path code created
+    // new ValueProfiles then the ValueProfiles would no longer be sorted by bytecode offset,
+    // which would break the invariant necessary to use CodeBlock::valueProfileForBytecodeOffset().
+    unsigned numberOfValueProfiles = m_codeBlock->numberOfValueProfiles();
+
+    for (Vector<SlowCaseEntry>::iterator iter = m_slowCases.begin(); iter != m_slowCases.end();) {
+        m_bytecodeOffset = iter->to;
+
+        unsigned firstTo = m_bytecodeOffset;
+
+        Instruction* currentInstruction = instructionsBegin + m_bytecodeOffset;
+        
+        RareCaseProfile* rareCaseProfile = 0;
+        if (shouldEmitProfiling())
+            rareCaseProfile = m_codeBlock->addRareCaseProfile(m_bytecodeOffset);
+
+#if ENABLE(JIT_VERBOSE)
+        dataLogF("Old JIT emitting slow code for bc#%u at offset 0x%lx.\n", m_bytecodeOffset, (long)debugOffset());
+#endif
+        
+        if (m_disassembler)
+            m_disassembler->setForBytecodeSlowPath(m_bytecodeOffset, label());
+
+        switch (m_interpreter->getOpcodeID(currentInstruction->u.opcode)) {
+        DEFINE_SLOWCASE_OP(op_add)
+        DEFINE_SLOWCASE_OP(op_bitand)
+        DEFINE_SLOWCASE_OP(op_bitor)
+        DEFINE_SLOWCASE_OP(op_bitxor)
+        DEFINE_SLOWCASE_OP(op_call)
+        DEFINE_SLOWCASE_OP(op_call_eval)
+        DEFINE_SLOWCASE_OP(op_call_varargs)
+        DEFINE_SLOWCASE_OP(op_construct_varargs)
+        DEFINE_SLOWCASE_OP(op_construct)
+        DEFINE_SLOWCASE_OP(op_to_this)
+        DEFINE_SLOWCASE_OP(op_check_tdz)
+        DEFINE_SLOWCASE_OP(op_create_this)
+        DEFINE_SLOWCASE_OP(op_div)
+        DEFINE_SLOWCASE_OP(op_eq)
+        case op_get_by_id_out_of_line:
+        case op_get_array_length:
+        DEFINE_SLOWCASE_OP(op_get_by_id)
+        DEFINE_SLOWCASE_OP(op_get_by_val)
+        DEFINE_SLOWCASE_OP(op_check_has_instance)
+        DEFINE_SLOWCASE_OP(op_instanceof)
+        DEFINE_SLOWCASE_OP(op_jfalse)
+        DEFINE_SLOWCASE_OP(op_jless)
+        DEFINE_SLOWCASE_OP(op_jlesseq)
+        DEFINE_SLOWCASE_OP(op_jgreater)
+        DEFINE_SLOWCASE_OP(op_jgreatereq)
+        DEFINE_SLOWCASE_OP(op_jnless)
+        DEFINE_SLOWCASE_OP(op_jnlesseq)
+        DEFINE_SLOWCASE_OP(op_jngreater)
+        DEFINE_SLOWCASE_OP(op_jngreatereq)
+        DEFINE_SLOWCASE_OP(op_jtrue)
+        DEFINE_SLOWCASE_OP(op_loop_hint)
+        DEFINE_SLOWCASE_OP(op_lshift)
+        DEFINE_SLOWCASE_OP(op_mod)
+        DEFINE_SLOWCASE_OP(op_mul)
+        DEFINE_SLOWCASE_OP(op_negate)
+        DEFINE_SLOWCASE_OP(op_neq)
+        DEFINE_SLOWCASE_OP(op_new_object)
+        DEFINE_SLOWCASE_OP(op_not)
+        DEFINE_SLOWCASE_OP(op_nstricteq)
+        DEFINE_SLOWCASE_OP(op_dec)
+        DEFINE_SLOWCASE_OP(op_inc)
+        case op_put_by_id_out_of_line:
+        case op_put_by_id_transition_direct:
+        case op_put_by_id_transition_normal:
+        case op_put_by_id_transition_direct_out_of_line:
+        case op_put_by_id_transition_normal_out_of_line:
+        DEFINE_SLOWCASE_OP(op_put_by_id)
+        case op_put_by_val_direct:
+        DEFINE_SLOWCASE_OP(op_put_by_val)
+        DEFINE_SLOWCASE_OP(op_rshift)
+        DEFINE_SLOWCASE_OP(op_unsigned)
+        DEFINE_SLOWCASE_OP(op_urshift)
+        DEFINE_SLOWCASE_OP(op_stricteq)
+        DEFINE_SLOWCASE_OP(op_sub)
+        DEFINE_SLOWCASE_OP(op_to_number)
+        DEFINE_SLOWCASE_OP(op_to_string)
+        DEFINE_SLOWCASE_OP(op_to_primitive)
+        DEFINE_SLOWCASE_OP(op_has_indexed_property)
+        DEFINE_SLOWCASE_OP(op_has_structure_property)
+        DEFINE_SLOWCASE_OP(op_get_direct_pname)
+
+        DEFINE_SLOWCASE_OP(op_resolve_scope)
+        DEFINE_SLOWCASE_OP(op_get_from_scope)
+        DEFINE_SLOWCASE_OP(op_put_to_scope)
+
+        default:
+            RELEASE_ASSERT_NOT_REACHED();
+        }
+
+        RELEASE_ASSERT_WITH_MESSAGE(iter == m_slowCases.end() || firstTo != iter->to, "Not enough jumps linked in slow case codegen.");
+        RELEASE_ASSERT_WITH_MESSAGE(firstTo == (iter - 1)->to, "Too many jumps linked in slow case codegen.");
+        
+        if (shouldEmitProfiling())
+            add32(TrustedImm32(1), AbsoluteAddress(&rareCaseProfile->m_counter));
+
+        emitJumpSlowToHot(jump(), 0);
+    }
+
+    RELEASE_ASSERT(m_getByIdIndex == m_getByIds.size());
+    RELEASE_ASSERT(m_putByIdIndex == m_putByIds.size());
+    RELEASE_ASSERT(m_callLinkInfoIndex == m_callCompilationInfo.size());
+    RELEASE_ASSERT(numberOfValueProfiles == m_codeBlock->numberOfValueProfiles());
+
+#ifndef NDEBUG
+    // Reset this, in order to guard its use with ASSERTs.
+    m_bytecodeOffset = std::numeric_limits<unsigned>::max();
+#endif
+}
+
+CompilationResult JIT::privateCompile(JITCompilationEffort effort)
+{
+    DFG::CapabilityLevel level = m_codeBlock->capabilityLevel();
+    switch (level) {
+    case DFG::CannotCompile:
+        m_canBeOptimized = false;
+        m_canBeOptimizedOrInlined = false;
+        m_shouldEmitProfiling = false;
+        break;
+    case DFG::CanCompile:
+    case DFG::CanCompileAndInline:
+        m_canBeOptimized = true;
+        m_canBeOptimizedOrInlined = true;
+        m_shouldEmitProfiling = true;
+        break;
+    default:
+        RELEASE_ASSERT_NOT_REACHED();
+        break;
+    }
+    
+    switch (m_codeBlock->codeType()) {
+    case GlobalCode:
+    case EvalCode:
+        m_codeBlock->m_shouldAlwaysBeInlined = false;
+        break;
+    case FunctionCode:
+        // We could have already set it to false because we detected an uninlineable call.
+        // Don't override that observation.
+        m_codeBlock->m_shouldAlwaysBeInlined &= canInline(level) && DFG::mightInlineFunction(m_codeBlock);
+        break;
+    }
+
+    // This ensures that we have the most up to date type information when performing typecheck optimizations for op_profile_type.
+    if (m_vm->typeProfiler())
+        m_vm->typeProfilerLog()->processLogEntries(ASCIILiteral("Preparing for JIT compilation."));
+    
+    if (Options::showDisassembly() || m_vm->m_perBytecodeProfiler)
+        m_disassembler = std::make_unique<JITDisassembler>(m_codeBlock);
+    if (m_vm->m_perBytecodeProfiler) {
+        m_compilation = adoptRef(
+            new Profiler::Compilation(
+                m_vm->m_perBytecodeProfiler->ensureBytecodesFor(m_codeBlock),
+                Profiler::Baseline));
+        m_compilation->addProfiledBytecodes(*m_vm->m_perBytecodeProfiler, m_codeBlock);
+    }
+    
+    if (m_disassembler)
+        m_disassembler->setStartOfCode(label());
+
+    // Just add a little bit of randomness to the codegen
+    if (m_randomGenerator.getUint32() & 1)
+        nop();
+
+    emitFunctionPrologue();
+    emitPutImmediateToCallFrameHeader(m_codeBlock, JSStack::CodeBlock);
+
+    Label beginLabel(this);
+
+    sampleCodeBlock(m_codeBlock);
+#if ENABLE(OPCODE_SAMPLING)
+    sampleInstruction(m_codeBlock->instructions().begin());
+#endif
+
+    if (m_codeBlock->codeType() == FunctionCode) {
+        ASSERT(m_bytecodeOffset == std::numeric_limits<unsigned>::max());
+        if (shouldEmitProfiling()) {
+            for (int argument = 0; argument < m_codeBlock->numParameters(); ++argument) {
+                // If this is a constructor, then we want to put in a dummy profiling site (to
+                // keep things consistent) but we don't actually want to record the dummy value.
+                if (m_codeBlock->m_isConstructor && !argument)
+                    continue;
+                int offset = CallFrame::argumentOffsetIncludingThis(argument) * static_cast<int>(sizeof(Register));
+#if USE(JSVALUE64)
+                load64(Address(callFrameRegister, offset), regT0);
+#elif USE(JSVALUE32_64)
+                load32(Address(callFrameRegister, offset + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
+                load32(Address(callFrameRegister, offset + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
+#endif
+                emitValueProfilingSite(m_codeBlock->valueProfileForArgument(argument));
+            }
+        }
+    }
+
+    addPtr(TrustedImm32(stackPointerOffsetFor(m_codeBlock) * sizeof(Register)), callFrameRegister, regT1);
+    Jump stackOverflow = branchPtr(Above, AbsoluteAddress(m_vm->addressOfStackLimit()), regT1);
+
+    move(regT1, stackPointerRegister);
+    checkStackPointerAlignment();
+
+    privateCompileMainPass();
+    privateCompileLinkPass();
+    privateCompileSlowCases();
+    
+    if (m_disassembler)
+        m_disassembler->setEndOfSlowPath(label());
+
+    stackOverflow.link(this);
+    m_bytecodeOffset = 0;
+    if (maxFrameExtentForSlowPathCall)
+        addPtr(TrustedImm32(-maxFrameExtentForSlowPathCall), stackPointerRegister);
+    callOperationWithCallFrameRollbackOnException(operationThrowStackOverflowError, m_codeBlock);
+
+    Label arityCheck;
+    if (m_codeBlock->codeType() == FunctionCode) {
+        arityCheck = label();
+        store8(TrustedImm32(0), &m_codeBlock->m_shouldAlwaysBeInlined);
+        emitFunctionPrologue();
+        emitPutImmediateToCallFrameHeader(m_codeBlock, JSStack::CodeBlock);
+
+        load32(payloadFor(JSStack::ArgumentCount), regT1);
+        branch32(AboveOrEqual, regT1, TrustedImm32(m_codeBlock->m_numParameters)).linkTo(beginLabel, this);
+
+        m_bytecodeOffset = 0;
+
+        if (maxFrameExtentForSlowPathCall)
+            addPtr(TrustedImm32(-maxFrameExtentForSlowPathCall), stackPointerRegister);
+        callOperationWithCallFrameRollbackOnException(m_codeBlock->m_isConstructor ? operationConstructArityCheck : operationCallArityCheck);
+        if (maxFrameExtentForSlowPathCall)
+            addPtr(TrustedImm32(maxFrameExtentForSlowPathCall), stackPointerRegister);
+        if (returnValueGPR != regT0)
+            move(returnValueGPR, regT0);
+        branchTest32(Zero, regT0).linkTo(beginLabel, this);
+        GPRReg thunkReg;
+#if USE(JSVALUE64)
+        thunkReg = GPRInfo::regT7;
+#else
+        thunkReg = GPRInfo::regT5;
+#endif
+        CodeLocationLabel* failThunkLabels =
+            m_vm->arityCheckFailReturnThunks->returnPCsFor(*m_vm, m_codeBlock->numParameters());
+        move(TrustedImmPtr(failThunkLabels), thunkReg);
+        loadPtr(BaseIndex(thunkReg, regT0, timesPtr()), thunkReg);
+        emitNakedCall(m_vm->getCTIStub(arityFixupGenerator).code());
+
+#if !ASSERT_DISABLED
+        m_bytecodeOffset = std::numeric_limits<unsigned>::max(); // Reset this, in order to guard its use with ASSERTs.
+#endif
+
+        jump(beginLabel);
+    }
+
+    ASSERT(m_jmpTable.isEmpty());
+    
+    privateCompileExceptionHandlers();
+    
+    if (m_disassembler)
+        m_disassembler->setEndOfCode(label());
+
+    LinkBuffer patchBuffer(*m_vm, *this, m_codeBlock, effort);
+    if (patchBuffer.didFailToAllocate())
+        return CompilationFailed;
+
+    // Translate vPC offsets into addresses in JIT generated code, for switch tables.
+    for (unsigned i = 0; i < m_switches.size(); ++i) {
+        SwitchRecord record = m_switches[i];
+        unsigned bytecodeOffset = record.bytecodeOffset;
+
+        if (record.type != SwitchRecord::String) {
+            ASSERT(record.type == SwitchRecord::Immediate || record.type == SwitchRecord::Character); 
+            ASSERT(record.jumpTable.simpleJumpTable->branchOffsets.size() == record.jumpTable.simpleJumpTable->ctiOffsets.size());
+
+            record.jumpTable.simpleJumpTable->ctiDefault = patchBuffer.locationOf(m_labels[bytecodeOffset + record.defaultOffset]);
+
+            for (unsigned j = 0; j < record.jumpTable.simpleJumpTable->branchOffsets.size(); ++j) {
+                unsigned offset = record.jumpTable.simpleJumpTable->branchOffsets[j];
+                record.jumpTable.simpleJumpTable->ctiOffsets[j] = offset ? patchBuffer.locationOf(m_labels[bytecodeOffset + offset]) : record.jumpTable.simpleJumpTable->ctiDefault;
+            }
+        } else {
+            ASSERT(record.type == SwitchRecord::String);
+
+            record.jumpTable.stringJumpTable->ctiDefault = patchBuffer.locationOf(m_labels[bytecodeOffset + record.defaultOffset]);
+
+            StringJumpTable::StringOffsetTable::iterator end = record.jumpTable.stringJumpTable->offsetTable.end();            
+            for (StringJumpTable::StringOffsetTable::iterator it = record.jumpTable.stringJumpTable->offsetTable.begin(); it != end; ++it) {
+                unsigned offset = it->value.branchOffset;
+                it->value.ctiOffset = offset ? patchBuffer.locationOf(m_labels[bytecodeOffset + offset]) : record.jumpTable.stringJumpTable->ctiDefault;
+            }
+        }
+    }
+
+    for (size_t i = 0; i < m_codeBlock->numberOfExceptionHandlers(); ++i) {
+        HandlerInfo& handler = m_codeBlock->exceptionHandler(i);
+        handler.nativeCode = patchBuffer.locationOf(m_labels[handler.target]);
+    }
+
+    for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
+        if (iter->to)
+            patchBuffer.link(iter->from, FunctionPtr(iter->to));
+    }
+
+    for (unsigned i = m_getByIds.size(); i--;)
+        m_getByIds[i].finalize(patchBuffer);
+    for (unsigned i = m_putByIds.size(); i--;)
+        m_putByIds[i].finalize(patchBuffer);
+
+    for (const auto& byValCompilationInfo : m_byValCompilationInfo) {
+        PatchableJump patchableNotIndexJump = byValCompilationInfo.notIndexJump;
+        CodeLocationJump notIndexJump = CodeLocationJump();
+        if (Jump(patchableNotIndexJump).isSet())
+            notIndexJump = CodeLocationJump(patchBuffer.locationOf(patchableNotIndexJump));
+        CodeLocationJump badTypeJump = CodeLocationJump(patchBuffer.locationOf(byValCompilationInfo.badTypeJump));
+        CodeLocationLabel doneTarget = patchBuffer.locationOf(byValCompilationInfo.doneTarget);
+        CodeLocationLabel nextHotPathTarget = patchBuffer.locationOf(byValCompilationInfo.nextHotPathTarget);
+        CodeLocationLabel slowPathTarget = patchBuffer.locationOf(byValCompilationInfo.slowPathTarget);
+        CodeLocationCall returnAddress = patchBuffer.locationOf(byValCompilationInfo.returnAddress);
+
+        *byValCompilationInfo.byValInfo = ByValInfo(
+            byValCompilationInfo.bytecodeIndex,
+            notIndexJump,
+            badTypeJump,
+            byValCompilationInfo.arrayMode,
+            byValCompilationInfo.arrayProfile,
+            differenceBetweenCodePtr(badTypeJump, doneTarget),
+            differenceBetweenCodePtr(badTypeJump, nextHotPathTarget),
+            differenceBetweenCodePtr(returnAddress, slowPathTarget));
+    }
+    for (unsigned i = 0; i < m_callCompilationInfo.size(); ++i) {
+        CallCompilationInfo& compilationInfo = m_callCompilationInfo[i];
+        CallLinkInfo& info = *compilationInfo.callLinkInfo;
+        info.setCallLocations(patchBuffer.locationOfNearCall(compilationInfo.callReturnLocation),
+            patchBuffer.locationOf(compilationInfo.hotPathBegin),
+            patchBuffer.locationOfNearCall(compilationInfo.hotPathOther));
+    }
+
+    CompactJITCodeMap::Encoder jitCodeMapEncoder;
+    for (unsigned bytecodeOffset = 0; bytecodeOffset < m_labels.size(); ++bytecodeOffset) {
+        if (m_labels[bytecodeOffset].isSet())
+            jitCodeMapEncoder.append(bytecodeOffset, patchBuffer.offsetOf(m_labels[bytecodeOffset]));
+    }
+    m_codeBlock->setJITCodeMap(jitCodeMapEncoder.finish());
+
+    MacroAssemblerCodePtr withArityCheck;
+    if (m_codeBlock->codeType() == FunctionCode)
+        withArityCheck = patchBuffer.locationOf(arityCheck);
+
+    if (Options::showDisassembly()) {
+        m_disassembler->dump(patchBuffer);
+        patchBuffer.didAlreadyDisassemble();
+    }
+    if (m_compilation) {
+        m_disassembler->reportToProfiler(m_compilation.get(), patchBuffer);
+        m_vm->m_perBytecodeProfiler->addCompilation(m_compilation);
+    }
+    
+    CodeRef result = FINALIZE_CODE(
+        patchBuffer,
+        ("Baseline JIT code for %s", toCString(CodeBlockWithJITType(m_codeBlock, JITCode::BaselineJIT)).data()));
+    
+    m_vm->machineCodeBytesPerBytecodeWordForBaselineJIT.add(
+        static_cast<double>(result.size()) /
+        static_cast<double>(m_codeBlock->instructions().size()));
+    
+    m_codeBlock->shrinkToFit(CodeBlock::LateShrink);
+    m_codeBlock->setJITCode(
+        adoptRef(new DirectJITCode(result, withArityCheck, JITCode::BaselineJIT)));
+    
+#if ENABLE(JIT_VERBOSE)
+    dataLogF("JIT generated code for %p at [%p, %p).\n", m_codeBlock, result.executableMemory()->start(), result.executableMemory()->end());
+#endif
+    
+    return CompilationSuccessful;
+}
+
+void JIT::privateCompileExceptionHandlers()
+{
+    if (!m_exceptionChecksWithCallFrameRollback.empty()) {
+        m_exceptionChecksWithCallFrameRollback.link(this);
+
+        // lookupExceptionHandlerFromCallerFrame is passed two arguments, the VM and the exec (the CallFrame*).
+
+        move(TrustedImmPtr(vm()), GPRInfo::argumentGPR0);
+        move(GPRInfo::callFrameRegister, GPRInfo::argumentGPR1);
+
+#if CPU(X86)
+        // FIXME: should use the call abstraction, but this is currently in the SpeculativeJIT layer!
+        poke(GPRInfo::argumentGPR0);
+        poke(GPRInfo::argumentGPR1, 1);
+#endif
+        m_calls.append(CallRecord(call(), std::numeric_limits<unsigned>::max(), FunctionPtr(lookupExceptionHandlerFromCallerFrame).value()));
+        jumpToExceptionHandler();
+    }
+
+    if (!m_exceptionChecks.empty()) {
+        m_exceptionChecks.link(this);
+
+        // lookupExceptionHandler is passed two arguments, the VM and the exec (the CallFrame*).
+        move(TrustedImmPtr(vm()), GPRInfo::argumentGPR0);
+        move(GPRInfo::callFrameRegister, GPRInfo::argumentGPR1);
+
+#if CPU(X86)
+        // FIXME: should use the call abstraction, but this is currently in the SpeculativeJIT layer!
+        poke(GPRInfo::argumentGPR0);
+        poke(GPRInfo::argumentGPR1, 1);
+#endif
+        m_calls.append(CallRecord(call(), std::numeric_limits<unsigned>::max(), FunctionPtr(lookupExceptionHandler).value()));
+        jumpToExceptionHandler();
+    }
+}
+
+unsigned JIT::frameRegisterCountFor(CodeBlock* codeBlock)
+{
+    ASSERT(static_cast<unsigned>(codeBlock->m_numCalleeRegisters) == WTF::roundUpToMultipleOf(stackAlignmentRegisters(), static_cast<unsigned>(codeBlock->m_numCalleeRegisters)));
+
+    return roundLocalRegisterCountForFramePointerOffset(codeBlock->m_numCalleeRegisters + maxFrameExtentForSlowPathCallInRegisters);
+}
+
+int JIT::stackPointerOffsetFor(CodeBlock* codeBlock)
+{
+    return virtualRegisterForLocal(frameRegisterCountFor(codeBlock) - 1).offset();
+}
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)