LSR: run DeleteDeadPhis before replaceCongruentPhis.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147711 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Andrew Trick 2012-01-07 01:36:44 +00:00
parent 63faf82d03
commit f231a6dc7f

View File

@ -3860,14 +3860,6 @@ LSRInstance::LSRInstance(const TargetLowering *tli, Loop *l, Pass *P)
// Skip nested loops until we can model them better with formulae.
if (!EnableNested && !L->empty()) {
if (EnablePhiElim) {
// Remove any extra phis created by processing inner loops.
SmallVector<WeakVH, 16> DeadInsts;
SCEVExpander Rewriter(SE, "lsr");
Changed |= (bool)Rewriter.replaceCongruentIVs(L, &DT, DeadInsts, TLI);
Changed |= (bool)DeleteTriviallyDeadInstructions(DeadInsts);
}
DEBUG(dbgs() << "LSR skipping outer loop " << *L << "\n");
return;
}
@ -3913,14 +3905,6 @@ LSRInstance::LSRInstance(const TargetLowering *tli, Loop *l, Pass *P)
// Now that we've decided what we want, make it so.
ImplementSolution(Solution, P);
if (EnablePhiElim) {
// Remove any extra phis created by processing inner loops.
SmallVector<WeakVH, 16> DeadInsts;
SCEVExpander Rewriter(SE, "lsr");
Changed |= (bool)Rewriter.replaceCongruentIVs(L, &DT, DeadInsts, TLI);
Changed |= (bool)DeleteTriviallyDeadInstructions(DeadInsts);
}
}
void LSRInstance::print_factors_and_types(raw_ostream &OS) const {
@ -4046,9 +4030,21 @@ bool LoopStrengthReduce::runOnLoop(Loop *L, LPPassManager & /*LPM*/) {
// Run the main LSR transformation.
Changed |= LSRInstance(TLI, L, this).getChanged();
// At this point, it is worth checking to see if any recurrence PHIs are also
// dead, so that we can remove them as well.
// Remove any extra phis created by processing inner loops.
Changed |= DeleteDeadPHIs(L->getHeader());
if (EnablePhiElim) {
SmallVector<WeakVH, 16> DeadInsts;
SCEVExpander Rewriter(getAnalysis<ScalarEvolution>(), "lsr");
#ifndef NDEBUG
Rewriter.setDebugType(DEBUG_TYPE);
#endif
unsigned numFolded = Rewriter.
replaceCongruentIVs(L, &getAnalysis<DominatorTree>(), DeadInsts, TLI);
if (numFolded) {
Changed = true;
DeleteTriviallyDeadInstructions(DeadInsts);
DeleteDeadPHIs(L->getHeader());
}
}
return Changed;
}