static bool safeToMoveGuard(TR::Block *destination, TR::TreeTop *guardCandidate,
TR::TreeTop *branchDest, TR_BitVector &privArgSymRefs)
{
static char *disablePrivArgMovement = feGetEnv("TR_DisableRuntimeGuardPrivArgMovement");
TR::TreeTop *start = destination ? destination->getExit() : TR::comp()->getStartTree();
if (guardCandidate->getNode()->isHCRGuard())
{
for (TR::TreeTop *tt = start; tt && tt != guardCandidate; tt = tt->getNextTreeTop())
{
if (tt->getNode()->canGCandReturn())
return false;
}
}
else if (guardCandidate->getNode()->isOSRGuard())
{
for (TR::TreeTop *tt = start; tt && tt != guardCandidate; tt = tt->getNextTreeTop())
{
if (TR::comp()->isPotentialOSRPoint(tt->getNode(), NULL, true))
return false;
}
}
else
{
privArgSymRefs.empty();
for (TR::TreeTop *tt = start; tt && tt != guardCandidate; tt = tt->getNextTreeTop())
{
// It's safe to move the guard if there are only priv arg stores and live monitor stores
// ahead of the guard
if (tt->getNode()->getOpCodeValue() != TR::BBStart
&& tt->getNode()->getOpCodeValue() != TR::BBEnd
&& !tt->getNode()->chkIsPrivatizedInlinerArg()
&& !(tt->getNode()->getOpCode().hasSymbolReference() && tt->getNode()->getSymbol()->holdsMonitoredObject())
&& !tt->getNode()->isNopableInlineGuard())
return false;
if (tt->getNode()->chkIsPrivatizedInlinerArg() && (disablePrivArgMovement ||
// If the priv arg is not for this guard
(guardCandidate->getNode()->getInlinedSiteIndex() > -1 &&
// if priv arg store does not have the same inlined site index as the guard's caller, that means it is not a priv arg for this guard,
// then we cannot move the guard and its priv args up across other calls' priv args
tt->getNode()->getInlinedSiteIndex() != TR::comp()->getInlinedCallSite(guardCandidate->getNode()->getInlinedSiteIndex())._byteCodeInfo.getCallerIndex())))
return false;
if (tt->getNode()->chkIsPrivatizedInlinerArg())
privArgSymRefs.set(tt->getNode()->getSymbolReference()->getReferenceNumber());
if (tt->getNode()->isNopableInlineGuard()
&& tt->getNode()->getBranchDestination() != branchDest)
return false;
}
}
return true;
}
/**
* Search for direct loads in the taken side of a guard
*
* @param firstBlock The guard's branch destination
* @param coldPathLoads BitVector of symbol reference numbers for any direct loads seen until the merge back to mainline
*/
static void collectColdPathLoads(TR::Block* firstBlock, TR_BitVector &coldPathLoads)
{
TR_Stack<TR::Block*> blocksToCheck(TR::comp()->trMemory(), 8, false, stackAlloc);
blocksToCheck.push(firstBlock);
TR::NodeChecklist checklist(TR::comp());
coldPathLoads.empty();
while (!blocksToCheck.isEmpty())
{
TR::Block *block = blocksToCheck.pop();
for (TR::TreeTop *tt = block->getFirstRealTreeTop(); tt->getNode()->getOpCodeValue() != TR::BBEnd; tt = tt->getNextTreeTop())
collectDirectLoads(tt->getNode(), coldPathLoads, checklist);
// Search for any successors that have not merged with the mainline
for (auto itr = block->getSuccessors().begin(), end = block->getSuccessors().end(); itr != end; ++itr)
{
TR::Block *dest = (*itr)->getTo()->asBlock();
if (dest != TR::comp()->getFlowGraph()->getEnd() && dest->getPredecessors().size() == 1)
blocksToCheck.push(dest);
}
}
}
void TR_ReachingDefinitions::initializeGenAndKillSetInfoForNode(TR::Node *node, TR_BitVector &defsKilled, bool seenException, int32_t blockNum, TR::Node *parent)
{
// Update gen and kill info for nodes in this subtree
//
int32_t i;
if (node->getVisitCount() == comp()->getVisitCount())
return;
node->setVisitCount(comp()->getVisitCount());
// Process the children first
//
for (i = node->getNumChildren()-1; i >= 0; --i)
{
initializeGenAndKillSetInfoForNode(node->getChild(i), defsKilled, seenException, blockNum, node);
}
bool irrelevantStore = false;
scount_t nodeIndex = node->getLocalIndex();
if (nodeIndex <= 0)
{
if (node->getOpCode().isStore() &&
node->getSymbol()->isAutoOrParm() &&
node->storedValueIsIrrelevant())
{
irrelevantStore = true;
}
else
return;
}
bool foundDefsToKill = false;
int32_t numDefNodes = 0;
defsKilled.empty();
TR::ILOpCode &opCode = node->getOpCode();
TR::SymbolReference *symRef;
TR::Symbol *sym;
uint16_t symIndex;
uint32_t num_aliases;
if (_useDefInfo->_useDefForRegs &&
(opCode.isLoadReg() ||
opCode.isStoreReg()))
{
sym = NULL;
symRef = NULL;
symIndex = _useDefInfo->getNumSymbols() + node->getGlobalRegisterNumber();
num_aliases = 1;
}
else
{
symRef = node->getSymbolReference();
sym = symRef->getSymbol();
symIndex = symRef->getSymbol()->getLocalIndex();
num_aliases = _useDefInfo->getNumAliases(symRef, _aux);
}
if (symIndex == NULL_USEDEF_SYMBOL_INDEX || node->getOpCode().isCall() || node->getOpCode().isFence() ||
(parent && parent->getOpCode().isResolveCheck() && num_aliases > 1))
{
// A call or unresolved reference is a definition of all
// symbols it is aliased with
//
numDefNodes = num_aliases;
//for all symbols that are a mustdef of a call, kill defs of those symbols
if (node->getOpCode().isCall())
foundDefsToKill = false;
}
else if (irrelevantStore || _useDefInfo->isExpandedDefIndex(nodeIndex))
{
// DefOnly node defines all symbols it is aliased with
// UseDef node(load) defines only the symbol itself
//
if (!irrelevantStore)
{
numDefNodes = num_aliases;
numDefNodes = _useDefInfo->isExpandedUseDefIndex(nodeIndex) ? 1 : numDefNodes;
if (!_useDefInfo->getDefsForSymbolIsZero(symIndex, _aux) &&
(!sym ||
(!sym->isShadow() &&
!sym->isMethod())))
{
foundDefsToKill = true;
// defsKilled ORed with defsForSymbol(symIndex);
_useDefInfo->getDefsForSymbol(defsKilled, symIndex, _aux);
}
if (node->getOpCode().isStoreIndirect())
{
int32_t memSymIndex = _useDefInfo->getMemorySymbolIndex(node);
if (memSymIndex != -1 &&
!_useDefInfo->getDefsForSymbolIsZero(memSymIndex, _aux))
{
foundDefsToKill = true;
// defsKilled ORed with defsForSymbol(symIndex);
_useDefInfo->getDefsForSymbol(defsKilled, memSymIndex, _aux);
}
}
}
else if (!_useDefInfo->getDefsForSymbolIsZero(symIndex, _aux))
{
numDefNodes = 1;
foundDefsToKill = true;
// defsKilled ORed with defsForSymbol(symIndex);
_useDefInfo->getDefsForSymbol(defsKilled, symIndex, _aux);
}
}
else
{
numDefNodes = 0;
}
if (foundDefsToKill)
{
if (_regularKillSetInfo[blockNum] == NULL)
allocateContainer(&_regularKillSetInfo[blockNum]);
*_regularKillSetInfo[blockNum] |= defsKilled;
if (!seenException)
{
if (_exceptionKillSetInfo[blockNum] == NULL)
allocateContainer(&_exceptionKillSetInfo[blockNum]);
*_exceptionKillSetInfo[blockNum] |= defsKilled;
}
}
if (_regularGenSetInfo[blockNum] == NULL)
allocateContainer(&_regularGenSetInfo[blockNum]);
else if (foundDefsToKill)
*_regularGenSetInfo[blockNum] -= defsKilled;
if (_exceptionGenSetInfo[blockNum] == NULL)
allocateContainer(&_exceptionGenSetInfo[blockNum]);
else if (foundDefsToKill && !seenException)
*_exceptionGenSetInfo[blockNum] -= defsKilled;
if (!irrelevantStore)
{
for (i = 0; i < numDefNodes; ++i)
{
_regularGenSetInfo[blockNum]->set(nodeIndex+i);
_exceptionGenSetInfo[blockNum]->set(nodeIndex+i);
}
}
else // fake up the method entry def as the def index to "gen" to avoid a use without a def completely
{
_regularGenSetInfo[blockNum]->set(sym->getLocalIndex());
_exceptionGenSetInfo[blockNum]->set(sym->getLocalIndex());
}
}
