[llvm] [LV][NFC] Emit remarks when failing to vectorise early exit loops (PR #225078)

[Luke Lau via llvm-commits]

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@@ -3227,8 +3251,13 @@ static bool handleUncountableExitsWithSideEffects(
     if (!isDereferenceableAndAlignedInLoop(
             PtrSCEV, cast<LoadInst>(Load->getUnderlyingInstr())->getAlign(),
             PSE.getSE()->getConstant(EltSize), TheLoop, *PSE.getSE(), DT, AC,
-            &Predicates))
+            &Predicates)) {
+      reportVectorizationFailure("Early exit loop with side effects contains "
+                                 "critical load that may fault.\n",
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lukel97 wrote:

Nit do we use the term "critical" load anywhere else? Can we explicitly write it out as something like "contains load used by the exit condition that may fault"

https://github.com/llvm/llvm-project/pull/225078