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/*
* Copyright (C) 2011 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 "DFGOSRExitCompiler.h"
#if ENABLE(DFG_JIT)
#include "CallFrame.h"
#include "DFGCommon.h"
#include "LinkBuffer.h"
#include "RepatchBuffer.h"
namespace JSC { namespace DFG {
extern "C" {
void compileOSRExit(ExecState* exec)
{
SamplingRegion samplingRegion("DFG OSR Exit Compilation");
CodeBlock* codeBlock = exec->codeBlock();
ASSERT(codeBlock);
ASSERT(codeBlock->getJITType() == JITCode::DFGJIT);
JSGlobalData* globalData = &exec->globalData();
uint32_t exitIndex = globalData->osrExitIndex;
OSRExit& exit = codeBlock->osrExit(exitIndex);
// Make sure all code on our inline stack is JIT compiled. This is necessary since
// we may opt to inline a code block even before it had ever been compiled by the
// JIT, but our OSR exit infrastructure currently only works if the target of the
// OSR exit is JIT code. This could be changed since there is nothing particularly
// hard about doing an OSR exit into the interpreter, but for now this seems to make
// sense in that if we're OSR exiting from inlined code of a DFG code block, then
// probably it's a good sign that the thing we're exiting into is hot. Even more
// interestingly, since the code was inlined, it may never otherwise get JIT
// compiled since the act of inlining it may ensure that it otherwise never runs.
for (CodeOrigin codeOrigin = exit.m_codeOrigin; codeOrigin.inlineCallFrame; codeOrigin = codeOrigin.inlineCallFrame->caller) {
static_cast<FunctionExecutable*>(codeOrigin.inlineCallFrame->executable.get())
->baselineCodeBlockFor(codeOrigin.inlineCallFrame->isCall ? CodeForCall : CodeForConstruct)
->jitCompile(exec);
}
// Compute the value recoveries.
Operands<ValueRecovery> operands;
codeBlock->variableEventStream().reconstruct(codeBlock, exit.m_codeOrigin, codeBlock->minifiedDFG(), exit.m_streamIndex, operands);
// There may be an override, for forward speculations.
if (!!exit.m_valueRecoveryOverride) {
operands.setOperand(
exit.m_valueRecoveryOverride->operand, exit.m_valueRecoveryOverride->recovery);
}
SpeculationRecovery* recovery = 0;
if (exit.m_recoveryIndex)
recovery = &codeBlock->speculationRecovery(exit.m_recoveryIndex - 1);
#if DFG_ENABLE(DEBUG_VERBOSE)
dataLog("Generating OSR exit #%u (seq#%u, bc#%u, @%u, %s) for code block %p.\n", exitIndex, exit.m_streamIndex, exit.m_codeOrigin.bytecodeIndex, exit.m_nodeIndex, exitKindToString(exit.m_kind), codeBlock);
#endif
{
CCallHelpers jit(globalData, codeBlock);
OSRExitCompiler exitCompiler(jit);
jit.jitAssertHasValidCallFrame();
exitCompiler.compileExit(exit, operands, recovery);
LinkBuffer patchBuffer(*globalData, &jit, codeBlock);
exit.m_code = FINALIZE_CODE_IF(
shouldShowDisassembly(),
patchBuffer,
("DFG OSR exit #%u (bc#%u, @%u, %s) from CodeBlock %p",
exitIndex, exit.m_codeOrigin.bytecodeIndex, exit.m_nodeIndex,
exitKindToString(exit.m_kind), codeBlock));
}
{
RepatchBuffer repatchBuffer(codeBlock);
repatchBuffer.relink(exit.m_check.codeLocationForRepatch(codeBlock), CodeLocationLabel(exit.m_code.code()));
}
globalData->osrExitJumpDestination = exit.m_code.code().executableAddress();
}
} // extern "C"
void OSRExitCompiler::handleExitCounts(const OSRExit& exit)
{
m_jit.add32(AssemblyHelpers::TrustedImm32(1), AssemblyHelpers::AbsoluteAddress(&exit.m_count));
m_jit.move(AssemblyHelpers::TrustedImmPtr(m_jit.codeBlock()), GPRInfo::regT0);
AssemblyHelpers::Jump tooFewFails;
m_jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()), GPRInfo::regT2);
m_jit.add32(AssemblyHelpers::TrustedImm32(1), GPRInfo::regT2);
m_jit.store32(GPRInfo::regT2, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()));
m_jit.move(AssemblyHelpers::TrustedImmPtr(m_jit.baselineCodeBlock()), GPRInfo::regT0);
tooFewFails = m_jit.branch32(AssemblyHelpers::BelowOrEqual, GPRInfo::regT2, AssemblyHelpers::TrustedImm32(m_jit.codeBlock()->exitCountThresholdForReoptimization()));
// Reoptimize as soon as possible.
#if !NUMBER_OF_ARGUMENT_REGISTERS
m_jit.poke(GPRInfo::regT0);
#else
m_jit.move(GPRInfo::regT0, GPRInfo::argumentGPR0);
ASSERT(GPRInfo::argumentGPR0 != GPRInfo::regT1);
#endif
m_jit.move(AssemblyHelpers::TrustedImmPtr(bitwise_cast<void*>(triggerReoptimizationNow)), GPRInfo::regT1);
m_jit.call(GPRInfo::regT1);
AssemblyHelpers::Jump doneAdjusting = m_jit.jump();
tooFewFails.link(&m_jit);
// Adjust the execution counter such that the target is to only optimize after a while.
int32_t targetValue =
ExecutionCounter::applyMemoryUsageHeuristicsAndConvertToInt(
m_jit.baselineCodeBlock()->counterValueForOptimizeAfterLongWarmUp(),
m_jit.baselineCodeBlock());
m_jit.store32(AssemblyHelpers::TrustedImm32(-targetValue), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecuteCounter()));
targetValue = ExecutionCounter::clippedThreshold(m_jit.codeBlock()->globalObject(), targetValue);
m_jit.store32(AssemblyHelpers::TrustedImm32(targetValue), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionActiveThreshold()));
m_jit.store32(AssemblyHelpers::TrustedImm32(ExecutionCounter::formattedTotalCount(targetValue)), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionTotalCount()));
doneAdjusting.link(&m_jit);
}
} } // namespace JSC::DFG
#endif // ENABLE(DFG_JIT)
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