Fix a bug that was causing major slowdowns in povray. This was due to LCSSA

not handling PHI nodes correctly when determining if a value was live-out.

This patch reduces the number of detected live-out variables in the testcase
from 6565 to 485.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28771 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2006-06-13 19:37:18 +00:00
parent 0e4dd01ffc
commit 7be3f1e078

View File

@ -91,6 +91,7 @@ const PassInfo *llvm::LCSSAID = X.getPassInfo();
/// runOnFunction - Process all loops in the function, inner-most out.
bool LCSSA::runOnFunction(Function &F) {
bool changed = false;
LI = &getAnalysis<LoopInfo>();
DF = &getAnalysis<DominanceFrontier>();
DT = &getAnalysis<DominatorTree>();
@ -107,7 +108,7 @@ bool LCSSA::runOnFunction(Function &F) {
bool LCSSA::visitSubloop(Loop* L) {
for (Loop::iterator I = L->begin(), E = L->end(); I != E; ++I)
visitSubloop(*I);
// Speed up queries by creating a sorted list of blocks
LoopBlocks.clear();
LoopBlocks.insert(LoopBlocks.end(), L->block_begin(), L->block_end());
@ -162,7 +163,6 @@ void LCSSA::processInstruction(Instruction* Instr,
phi = new PHINode(Instr->getType(), Instr->getName()+".lcssa",
(*BBI)->begin());
workList.push_back(cast<PHINode>(phi));
Phis[*BBI] = phi;
}
}
@ -253,6 +253,11 @@ SetVector<Instruction*> LCSSA::getLoopValuesUsedOutsideLoop(Loop *L) {
for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E;
++UI) {
BasicBlock *UserBB = cast<Instruction>(*UI)->getParent();
if (PHINode* p = dyn_cast<PHINode>(*UI)) {
unsigned OperandNo = UI.getOperandNo();
UserBB = p->getIncomingBlock(OperandNo/2);
}
if (!inLoop(UserBB)) {
AffectedValues.insert(I);
break;