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::JumpList tooFewFails;
if (exit.m_kind == InadequateCoverage) {
// Proceed based on the assumption that we can profitably optimize this code once
// it has executed enough times.
m_jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfForcedOSRExitCounter()), GPRInfo::regT2);
m_jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfSpeculativeSuccessCounter()), GPRInfo::regT1);
m_jit.add32(AssemblyHelpers::TrustedImm32(1), GPRInfo::regT2);
m_jit.add32(AssemblyHelpers::TrustedImm32(-1), GPRInfo::regT1);
m_jit.store32(GPRInfo::regT2, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfForcedOSRExitCounter()));
m_jit.store32(GPRInfo::regT1, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfSpeculativeSuccessCounter()));
tooFewFails.append(m_jit.branch32(AssemblyHelpers::BelowOrEqual, GPRInfo::regT2, AssemblyHelpers::TrustedImm32(Options::forcedOSRExitCountForReoptimization)));
} else {
// Proceed based on the assumption that we can handle these exits so long as they
// don't get too frequent.
m_jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfSpeculativeFailCounter()), GPRInfo::regT2);
m_jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfSpeculativeSuccessCounter()), GPRInfo::regT1);
m_jit.add32(AssemblyHelpers::TrustedImm32(1), GPRInfo::regT2);
m_jit.add32(AssemblyHelpers::TrustedImm32(-1), GPRInfo::regT1);
m_jit.store32(GPRInfo::regT2, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfSpeculativeFailCounter()));
m_jit.store32(GPRInfo::regT1, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfSpeculativeSuccessCounter()));
m_jit.move(AssemblyHelpers::TrustedImmPtr(m_jit.baselineCodeBlock()), GPRInfo::regT0);
tooFewFails.append(m_jit.branch32(AssemblyHelpers::BelowOrEqual, GPRInfo::regT2, AssemblyHelpers::TrustedImm32(m_jit.codeBlock()->largeFailCountThreshold())));
m_jit.mul32(AssemblyHelpers::TrustedImm32(Options::desiredSpeculativeSuccessFailRatio), GPRInfo::regT2, GPRInfo::regT2);
tooFewFails.append(m_jit.branch32(AssemblyHelpers::BelowOrEqual, GPRInfo::regT2, GPRInfo::regT1));
}
// Reoptimize as soon as possible.
m_jit.store32(AssemblyHelpers::TrustedImm32(0), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecuteCounter()));
m_jit.store32(AssemblyHelpers::TrustedImm32(0), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionActiveThreshold()));
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()));
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);
}
AssemblyHelpers::JumpList AssemblyHelpers::branchIfNotType(
JSValueRegs regs, GPRReg tempGPR, const InferredType::Descriptor& descriptor, TagRegistersMode mode)
{
AssemblyHelpers::JumpList result;
switch (descriptor.kind()) {
case InferredType::Bottom:
result.append(jump());
break;
case InferredType::Boolean:
result.append(branchIfNotBoolean(regs, tempGPR));
break;
case InferredType::Other:
result.append(branchIfNotOther(regs, tempGPR));
break;
case InferredType::Int32:
result.append(branchIfNotInt32(regs, mode));
break;
case InferredType::Number:
result.append(branchIfNotNumber(regs, tempGPR, mode));
break;
case InferredType::String:
result.append(branchIfNotCell(regs, mode));
result.append(branchIfNotString(regs.payloadGPR()));
break;
case InferredType::ObjectWithStructure:
result.append(branchIfNotCell(regs, mode));
result.append(
branchStructure(
NotEqual,
Address(regs.payloadGPR(), JSCell::structureIDOffset()),
descriptor.structure()));
break;
case InferredType::ObjectWithStructureOrOther: {
Jump ok = branchIfOther(regs, tempGPR);
result.append(branchIfNotCell(regs, mode));
result.append(
branchStructure(
NotEqual,
Address(regs.payloadGPR(), JSCell::structureIDOffset()),
descriptor.structure()));
ok.link(this);
break;
}
case InferredType::Object:
result.append(branchIfNotCell(regs, mode));
result.append(branchIfNotObject(regs.payloadGPR()));
break;
case InferredType::ObjectOrOther: {
Jump ok = branchIfOther(regs, tempGPR);
result.append(branchIfNotCell(regs, mode));
result.append(branchIfNotObject(regs.payloadGPR()));
ok.link(this);
break;
}
case InferredType::Top:
break;
}
return result;
}
void handleExitCounts(CCallHelpers& jit, const OSRExitBase& exit)
{
jit.add32(AssemblyHelpers::TrustedImm32(1), AssemblyHelpers::AbsoluteAddress(&exit.m_count));
jit.move(AssemblyHelpers::TrustedImmPtr(jit.codeBlock()), GPRInfo::regT0);
AssemblyHelpers::Jump tooFewFails;
jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()), GPRInfo::regT2);
jit.add32(AssemblyHelpers::TrustedImm32(1), GPRInfo::regT2);
jit.store32(GPRInfo::regT2, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()));
jit.move(AssemblyHelpers::TrustedImmPtr(jit.baselineCodeBlock()), GPRInfo::regT0);
AssemblyHelpers::Jump reoptimizeNow = jit.branch32(
AssemblyHelpers::GreaterThanOrEqual,
AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecuteCounter()),
AssemblyHelpers::TrustedImm32(0));
// We want to figure out if there's a possibility that we're in a loop. For the outermost
// code block in the inline stack, we handle this appropriately by having the loop OSR trigger
// check the exit count of the replacement of the CodeBlock from which we are OSRing. The
// problem is the inlined functions, which might also have loops, but whose baseline versions
// don't know where to look for the exit count. Figure out if those loops are severe enough
// that we had tried to OSR enter. If so, then we should use the loop reoptimization trigger.
// Otherwise, we should use the normal reoptimization trigger.
AssemblyHelpers::JumpList loopThreshold;
for (InlineCallFrame* inlineCallFrame = exit.m_codeOrigin.inlineCallFrame; inlineCallFrame; inlineCallFrame = inlineCallFrame->caller.inlineCallFrame) {
loopThreshold.append(
jit.branchTest8(
AssemblyHelpers::NonZero,
AssemblyHelpers::AbsoluteAddress(
inlineCallFrame->executable->addressOfDidTryToEnterInLoop())));
}
jit.move(
AssemblyHelpers::TrustedImm32(jit.codeBlock()->exitCountThresholdForReoptimization()),
GPRInfo::regT1);
if (!loopThreshold.empty()) {
AssemblyHelpers::Jump done = jit.jump();
loopThreshold.link(&jit);
jit.move(
AssemblyHelpers::TrustedImm32(
jit.codeBlock()->exitCountThresholdForReoptimizationFromLoop()),
GPRInfo::regT1);
done.link(&jit);
}
tooFewFails = jit.branch32(AssemblyHelpers::BelowOrEqual, GPRInfo::regT2, GPRInfo::regT1);
reoptimizeNow.link(&jit);
// Reoptimize as soon as possible.
#if !NUMBER_OF_ARGUMENT_REGISTERS
jit.poke(GPRInfo::regT0);
jit.poke(AssemblyHelpers::TrustedImmPtr(&exit), 1);
#else
jit.move(GPRInfo::regT0, GPRInfo::argumentGPR0);
jit.move(AssemblyHelpers::TrustedImmPtr(&exit), GPRInfo::argumentGPR1);
#endif
jit.move(AssemblyHelpers::TrustedImmPtr(bitwise_cast<void*>(triggerReoptimizationNow)), GPRInfo::nonArgGPR0);
jit.call(GPRInfo::nonArgGPR0);
AssemblyHelpers::Jump doneAdjusting = jit.jump();
tooFewFails.link(&jit);
// Adjust the execution counter such that the target is to only optimize after a while.
int32_t activeThreshold =
jit.baselineCodeBlock()->adjustedCounterValue(
Options::thresholdForOptimizeAfterLongWarmUp());
int32_t targetValue = applyMemoryUsageHeuristicsAndConvertToInt(
activeThreshold, jit.baselineCodeBlock());
int32_t clippedValue;
switch (jit.codeBlock()->jitType()) {
case JITCode::DFGJIT:
clippedValue = BaselineExecutionCounter::clippedThreshold(jit.codeBlock()->globalObject(), targetValue);
break;
case JITCode::FTLJIT:
clippedValue = UpperTierExecutionCounter::clippedThreshold(jit.codeBlock()->globalObject(), targetValue);
break;
default:
RELEASE_ASSERT_NOT_REACHED();
#if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
clippedValue = 0; // Make some compilers, and mhahnenberg, happy.
#endif
break;
}
jit.store32(AssemblyHelpers::TrustedImm32(-clippedValue), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecuteCounter()));
jit.store32(AssemblyHelpers::TrustedImm32(activeThreshold), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionActiveThreshold()));
jit.store32(AssemblyHelpers::TrustedImm32(formattedTotalExecutionCount(clippedValue)), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionTotalCount()));
doneAdjusting.link(&jit);
}