LSR: run DeleteDeadPhis before replaceCongruentPhis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147711 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index ec0c9a6..f59e156 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -3860,14 +3860,6 @@
// 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 @@
// 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 @@
// 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;
}