// Process the structure recursively
//
int32_t
TR_ExpressionsSimplification::perform(TR_Structure * str)
{
if (trace())
traceMsg(comp(), "Analyzing root Structure : %p\n", str);
TR_RegionStructure *region;
// Only regions can be simplified
//
if (!(region = str->asRegion()))
return 0;
TR_RegionStructure::Cursor it(*region);
for (TR_StructureSubGraphNode *node = it.getCurrent();
node != 0;
node = it.getNext())
{
// Too strict
/*
if ((node->getPredecessors().size() == 1))
{
TR::CFGEdge *edge = node->getPredecessors().front();
TR_StructureSubGraphNode *pred = toStructureSubGraphNode(edge->getFrom());
TR_BlockStructure *b = pred->getStructure()->asBlock();
if (b && pred->getSuccessors().size() == 1))
perform(node->getStructure());
}
*/
perform(node->getStructure());
}
// debug only
//
/*
if (region->isNaturalLoop() &&
(region->getParent() &&
!region->getParent()->asRegion()->isCanonicalizedLoop()))
{
traceMsg(comp(), "Loop not canonicalized %x\n", region);
}
*/
TR::Block *entryBlock = region->getEntryBlock();
if (region->isNaturalLoop() && !entryBlock->isCold() &&
(region->getParent() /* &&
region->getParent()->asRegion()->isCanonicalizedLoop() */))
{
if (trace())
traceMsg(comp(), "Found candidate non cold loop %p for expression elimination\n", region);
findAndSimplifyInvariantLoopExpressions(region);
}
return 1; // Need to specify the cost
}
static void computeInvarianceOfAllStructures(TR::Compilation *comp, TR_Structure * s)
{
TR_RegionStructure *region = s->asRegion();
if (region)
{
TR_StructureSubGraphNode *node;
TR_RegionStructure::Cursor si(*region);
for (node = si.getCurrent(); node != NULL; node = si.getNext())
computeInvarianceOfAllStructures(comp, node->getStructure());
region->resetInvariance();
if (region->isNaturalLoop() /*|| region->containsInternalCycles() */)
{
region->computeInvariantExpressions();
}
}
}
TR::TreeTop *
OMR::Simplifier::simplifyExtendedBlock(TR::TreeTop * treeTop)
{
TR::Block * block = 0;
_containingStructure = NULL;
_blockRemoved = false;
for (; treeTop; treeTop = treeTop->getNextTreeTop())
{
TR::Node * node = treeTop->getNode();
TR_ASSERT(node->getOpCodeValue() == TR::BBStart, "Simplification, expected BBStart treetop");
TR::Block * b = node->getBlock();
if (block && !b->isExtensionOfPreviousBlock())
break;
if (b->isOSRCodeBlock() || b->isOSRCatchBlock())
{
b->setHasBeenVisited();
treeTop = b->getExit();
continue;
}
#ifdef DEBUG
if (block != b)
b->setHasBeenVisited();
#endif
if (!block && _reassociate &&
comp()->getFlowGraph()->getStructure() != NULL // [99391] getStructureOf() only valid if structure isn't invalidated
)
{ // b is first block in the extended block
TR_BlockStructure *blockStructure = b->getStructureOf();
if(blockStructure)
{
TR_Structure *parent = blockStructure->getParent();
while (parent)
{
TR_RegionStructure *region = parent->asRegion();
if (region->isNaturalLoop() /* || region->containsInternalCycles() */)
{
_containingStructure = region;
break;
}
parent = parent->getParent();
}
}
}
block = b;
if (trace())
traceMsg(comp(), "simplifying block_%d\n", block->getNumber());
_performLowerTreeSimplifier=NULL;
_performLowerTreeNode=NULL;
simplify(block);
if(_performLowerTreeSimplifier)
{
_performLowerTreeNode = postWalkLowerTreeSimplifier(_performLowerTreeSimplifier, _performLowerTreeNode, block, (TR::Simplifier *) this);
_performLowerTreeSimplifier->setNode(_performLowerTreeNode);
}
// If the block itself was removed from the CFG during simplification, find
// the next 'legitimate' block to be simplified
//
//if (comp()->getFlowGraph()->getRemovedNodes().find(block))
if(block->nodeIsRemoved())
{
TR::TreeTop * tt = findNextLegalTreeTop(comp(), block);
// in certain cases the removed block might be the last one we haven't
// visited and therefore we won't be able to find a treetop to continue
// in such cases we exit the loop
//
treeTop = tt ? tt->getPrevTreeTop() : 0;
if (!treeTop)
break;
}
else
{
treeTop = block->getExit();
}
}
// now remove any unreachable blocks
//
if (_blockRemoved)
{
// if the next block to be processed has been removed,
// find the next valid block to process
//
if (treeTop)
{
TR::Block *b = treeTop->getNode()->getBlock();
//if (comp()->getFlowGraph()->getRemovedNodes().find(b))
if(b->nodeIsRemoved())
treeTop = findNextLegalTreeTop(comp(), b);
}
}
return treeTop;
}
