CallLinkStatus.cpp [plain text]
#include "config.h"
#include "CallLinkStatus.h"
#include "BytecodeStructs.h"
#include "CallLinkInfo.h"
#include "CodeBlock.h"
#include "DFGJITCode.h"
#include "InlineCallFrame.h"
#include "InterpreterInlines.h"
#include "LLIntCallLinkInfo.h"
#include "JSCInlines.h"
#include <wtf/CommaPrinter.h>
#include <wtf/ListDump.h>
namespace JSC {
namespace CallLinkStatusInternal {
static const bool verbose = false;
}
CallLinkStatus::CallLinkStatus(JSValue value)
: m_couldTakeSlowPath(false)
, m_isProved(false)
{
if (!value || !value.isCell()) {
m_couldTakeSlowPath = true;
return;
}
m_variants.append(CallVariant(value.asCell()));
}
CallLinkStatus CallLinkStatus::computeFromLLInt(const ConcurrentJSLocker&, CodeBlock* profiledBlock, unsigned bytecodeIndex)
{
UNUSED_PARAM(profiledBlock);
UNUSED_PARAM(bytecodeIndex);
#if ENABLE(DFG_JIT)
if (profiledBlock->unlinkedCodeBlock()->hasExitSite(DFG::FrequentExitSite(bytecodeIndex, BadCell))) {
return takesSlowPath();
}
#endif
auto instruction = profiledBlock->instructions().at(bytecodeIndex);
OpcodeID op = instruction->opcodeID();
LLIntCallLinkInfo* callLinkInfo;
switch (op) {
case op_call:
callLinkInfo = &instruction->as<OpCall>().metadata(profiledBlock).m_callLinkInfo;
break;
case op_construct:
callLinkInfo = &instruction->as<OpConstruct>().metadata(profiledBlock).m_callLinkInfo;
break;
case op_tail_call:
callLinkInfo = &instruction->as<OpTailCall>().metadata(profiledBlock).m_callLinkInfo;
break;
default:
return CallLinkStatus();
}
return CallLinkStatus(callLinkInfo->lastSeenCallee.get());
}
CallLinkStatus CallLinkStatus::computeFor(
CodeBlock* profiledBlock, unsigned bytecodeIndex, const ICStatusMap& map,
ExitSiteData exitSiteData)
{
ConcurrentJSLocker locker(profiledBlock->m_lock);
UNUSED_PARAM(profiledBlock);
UNUSED_PARAM(bytecodeIndex);
UNUSED_PARAM(map);
UNUSED_PARAM(exitSiteData);
#if ENABLE(DFG_JIT)
CallLinkInfo* callLinkInfo = map.get(CodeOrigin(bytecodeIndex)).callLinkInfo;
if (!callLinkInfo) {
if (exitSiteData.takesSlowPath)
return takesSlowPath();
return computeFromLLInt(locker, profiledBlock, bytecodeIndex);
}
return computeFor(locker, profiledBlock, *callLinkInfo, exitSiteData);
#else
return CallLinkStatus();
#endif
}
CallLinkStatus CallLinkStatus::computeFor(
CodeBlock* profiledBlock, unsigned bytecodeIndex, const ICStatusMap& map)
{
return computeFor(profiledBlock, bytecodeIndex, map, computeExitSiteData(profiledBlock, bytecodeIndex));
}
CallLinkStatus::ExitSiteData CallLinkStatus::computeExitSiteData(CodeBlock* profiledBlock, unsigned bytecodeIndex)
{
ExitSiteData exitSiteData;
#if ENABLE(DFG_JIT)
UnlinkedCodeBlock* codeBlock = profiledBlock->unlinkedCodeBlock();
ConcurrentJSLocker locker(codeBlock->m_lock);
auto takesSlowPath = [&] (ExitingInlineKind inlineKind) -> ExitFlag {
return ExitFlag(
codeBlock->hasExitSite(locker, DFG::FrequentExitSite(bytecodeIndex, BadType, ExitFromAnything, inlineKind))
|| codeBlock->hasExitSite(locker, DFG::FrequentExitSite(bytecodeIndex, BadExecutable, ExitFromAnything, inlineKind)),
inlineKind);
};
auto badFunction = [&] (ExitingInlineKind inlineKind) -> ExitFlag {
return ExitFlag(codeBlock->hasExitSite(locker, DFG::FrequentExitSite(bytecodeIndex, BadCell, ExitFromAnything, inlineKind)), inlineKind);
};
exitSiteData.takesSlowPath |= takesSlowPath(ExitFromNotInlined);
exitSiteData.takesSlowPath |= takesSlowPath(ExitFromInlined);
exitSiteData.badFunction |= badFunction(ExitFromNotInlined);
exitSiteData.badFunction |= badFunction(ExitFromInlined);
#else
UNUSED_PARAM(profiledBlock);
UNUSED_PARAM(bytecodeIndex);
#endif
return exitSiteData;
}
#if ENABLE(JIT)
CallLinkStatus CallLinkStatus::computeFor(
const ConcurrentJSLocker& locker, CodeBlock* profiledBlock, CallLinkInfo& callLinkInfo)
{
UNUSED_PARAM(profiledBlock);
CallLinkStatus result = computeFromCallLinkInfo(locker, callLinkInfo);
result.m_maxNumArguments = callLinkInfo.maxNumArguments();
return result;
}
CallLinkStatus CallLinkStatus::computeFromCallLinkInfo(
const ConcurrentJSLocker&, CallLinkInfo& callLinkInfo)
{
if (callLinkInfo.isDirect())
return CallLinkStatus();
if (callLinkInfo.clearedByGC() || callLinkInfo.clearedByVirtual())
return takesSlowPath();
if (PolymorphicCallStubRoutine* stub = callLinkInfo.stub()) {
WTF::loadLoadFence();
if (!stub->hasEdges()) {
return takesSlowPath();
}
CallEdgeList edges = stub->edges();
RELEASE_ASSERT(edges.size());
std::sort(
edges.begin(), edges.end(),
[] (CallEdge a, CallEdge b) {
return a.count() > b.count();
});
RELEASE_ASSERT(edges.first().count() >= edges.last().count());
double totalCallsToKnown = 0;
double totalCallsToUnknown = callLinkInfo.slowPathCount();
CallVariantList variants;
for (size_t i = 0; i < edges.size(); ++i) {
CallEdge edge = edges[i];
if (i >= Options::maxPolymorphicCallVariantsForInlining()
|| edge.count() < Options::frequentCallThreshold())
totalCallsToUnknown += edge.count();
else {
totalCallsToKnown += edge.count();
variants.append(edge.callee());
}
}
RELEASE_ASSERT(!!totalCallsToKnown == !!variants.size());
if (variants.isEmpty())
return takesSlowPath();
if (totalCallsToKnown / totalCallsToUnknown < Options::minimumCallToKnownRate())
return takesSlowPath();
RELEASE_ASSERT(totalCallsToKnown);
RELEASE_ASSERT(variants.size());
CallLinkStatus result;
result.m_variants = variants;
result.m_couldTakeSlowPath = !!totalCallsToUnknown;
result.m_isBasedOnStub = true;
return result;
}
CallLinkStatus result;
if (JSObject* target = callLinkInfo.lastSeenCallee()) {
CallVariant variant(target);
if (callLinkInfo.hasSeenClosure())
variant = variant.despecifiedClosure();
result.m_variants.append(variant);
}
result.m_couldTakeSlowPath = !!callLinkInfo.slowPathCount();
return result;
}
CallLinkStatus CallLinkStatus::computeFor(
const ConcurrentJSLocker& locker, CodeBlock* profiledBlock, CallLinkInfo& callLinkInfo,
ExitSiteData exitSiteData, ExitingInlineKind inlineKind)
{
CallLinkStatus result = computeFor(locker, profiledBlock, callLinkInfo);
result.accountForExits(exitSiteData, inlineKind);
return result;
}
void CallLinkStatus::accountForExits(ExitSiteData exitSiteData, ExitingInlineKind inlineKind)
{
if (exitSiteData.badFunction.isSet(inlineKind)) {
if (isBasedOnStub()) {
makeClosureCall();
} else {
m_couldTakeSlowPath = true;
}
}
if (exitSiteData.takesSlowPath.isSet(inlineKind))
m_couldTakeSlowPath = true;
}
CallLinkStatus CallLinkStatus::computeFor(
CodeBlock* profiledBlock, CodeOrigin codeOrigin,
const ICStatusMap& baselineMap, const ICStatusContextStack& optimizedStack)
{
if (CallLinkStatusInternal::verbose)
dataLog("Figuring out call profiling for ", codeOrigin, "\n");
ExitSiteData exitSiteData = computeExitSiteData(profiledBlock, codeOrigin.bytecodeIndex);
if (CallLinkStatusInternal::verbose) {
dataLog("takesSlowPath = ", exitSiteData.takesSlowPath, "\n");
dataLog("badFunction = ", exitSiteData.badFunction, "\n");
}
for (const ICStatusContext* context : optimizedStack) {
if (CallLinkStatusInternal::verbose)
dataLog("Examining status in ", pointerDump(context->optimizedCodeBlock), "\n");
ICStatus status = context->get(codeOrigin);
bool checkStatusFirst = context->optimizedCodeBlock->jitType() == JITCode::FTLJIT;
auto bless = [&] (CallLinkStatus& result) {
if (!context->isInlined(codeOrigin))
result.merge(computeFor(profiledBlock, codeOrigin.bytecodeIndex, baselineMap, exitSiteData));
};
auto checkInfo = [&] () -> CallLinkStatus {
if (!status.callLinkInfo)
return CallLinkStatus();
if (CallLinkStatusInternal::verbose)
dataLog("Have CallLinkInfo with CodeOrigin = ", status.callLinkInfo->codeOrigin(), "\n");
CallLinkStatus result;
{
ConcurrentJSLocker locker(context->optimizedCodeBlock->m_lock);
result = computeFor(
locker, context->optimizedCodeBlock, *status.callLinkInfo, exitSiteData,
context->inlineKind(codeOrigin));
if (CallLinkStatusInternal::verbose)
dataLog("Got result: ", result, "\n");
}
bless(result);
return result;
};
auto checkStatus = [&] () -> CallLinkStatus {
if (!status.callStatus)
return CallLinkStatus();
CallLinkStatus result = *status.callStatus;
if (CallLinkStatusInternal::verbose)
dataLog("Have callStatus: ", result, "\n");
result.accountForExits(exitSiteData, context->inlineKind(codeOrigin));
bless(result);
return result;
};
if (checkStatusFirst) {
if (CallLinkStatus result = checkStatus())
return result;
if (CallLinkStatus result = checkInfo())
return result;
continue;
}
if (CallLinkStatus result = checkInfo())
return result;
if (CallLinkStatus result = checkStatus())
return result;
}
return computeFor(profiledBlock, codeOrigin.bytecodeIndex, baselineMap, exitSiteData);
}
#endif
void CallLinkStatus::setProvenConstantCallee(CallVariant variant)
{
m_variants = CallVariantList{ variant };
m_couldTakeSlowPath = false;
m_isProved = true;
}
bool CallLinkStatus::isClosureCall() const
{
for (unsigned i = m_variants.size(); i--;) {
if (m_variants[i].isClosureCall())
return true;
}
return false;
}
void CallLinkStatus::makeClosureCall()
{
m_variants = despecifiedVariantList(m_variants);
}
bool CallLinkStatus::finalize()
{
for (CallVariant& variant : m_variants) {
if (!variant.finalize())
return false;
}
return true;
}
void CallLinkStatus::merge(const CallLinkStatus& other)
{
m_couldTakeSlowPath |= other.m_couldTakeSlowPath;
for (const CallVariant& otherVariant : other.m_variants) {
bool found = false;
for (CallVariant& thisVariant : m_variants) {
if (thisVariant.merge(otherVariant)) {
found = true;
break;
}
}
if (!found)
m_variants.append(otherVariant);
}
}
void CallLinkStatus::filter(VM& vm, JSValue value)
{
m_variants.removeAllMatching(
[&] (CallVariant& variant) -> bool {
variant.filter(vm, value);
return !variant;
});
}
void CallLinkStatus::dump(PrintStream& out) const
{
if (!isSet()) {
out.print("Not Set");
return;
}
CommaPrinter comma;
if (m_isProved)
out.print(comma, "Statically Proved");
if (m_couldTakeSlowPath)
out.print(comma, "Could Take Slow Path");
if (m_isBasedOnStub)
out.print(comma, "Based On Stub");
if (!m_variants.isEmpty())
out.print(comma, listDump(m_variants));
if (m_maxNumArguments)
out.print(comma, "maxNumArguments = ", m_maxNumArguments);
}
}