[llvm] [LV][VPlan] Add initial support for CSA vectorization (PR #106560)

[Ramkumar Ramachandra via llvm-commits]

================
@@ -1564,11 +1586,15 @@ bool LoopVectorizationLegality::canFoldTailByMasking() const {
   for (const auto &Reduction : getReductionVars())
     ReductionLiveOuts.insert(Reduction.second.getLoopExitInstr());
 
+  SmallPtrSet<const Value *, 8> CSALiveOuts;
+  for (const auto &CSA : getCSAs())
+    CSALiveOuts.insert(CSA.second.getAssignment());
+
   // TODO: handle non-reduction outside users when tail is folded by masking.
   for (auto *AE : AllowedExit) {
     // Check that all users of allowed exit values are inside the loop or
-    // are the live-out of a reduction.
----------------
artagnon wrote:

Very minor nit: period ending sentence dropped?

https://github.com/llvm/llvm-project/pull/106560