[llvm] [LoopIdiomVectorize] Bail when vectorization is disabled (PR #181142)

[Aiden Grossman via llvm-commits]

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@@ -199,7 +204,17 @@ PreservedAnalyses LoopIdiomVectorizePass::run(Loop &L, LoopAnalysisManager &AM,
   if (ByteCmpVF.getNumOccurrences())
     BCVF = ByteCmpVF;
 
-  LoopIdiomVectorize LIV(VecStyle, BCVF, &AR.DT, &AR.LI, &AR.TTI, DL);
+  Function &F = *L.getHeader()->getParent();
+  auto &FAMP = AM.getResult<FunctionAnalysisManagerLoopProxy>(L, AR);
+  auto *ORE = FAMP.getCachedResult<OptimizationRemarkEmitterAnalysis>(F);
+
+  std::optional<OptimizationRemarkEmitter> ORELocal;
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boomanaiden154 wrote:

Keeping it optional to keep it on the stack SGTM.

We need to ensure the ORE is required from the function pipeline, and I'm not sure of the guarantees there. If we're confident it is always available, we can just assert/error that `ORE != nullptr`.

https://github.com/llvm/llvm-project/pull/181142