[llvm] [LoopVectorize] Teach LoopVectorizationLegality about more early exits (PR #107004)

[Paul Walker via llvm-commits]

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@@ -9802,6 +9802,12 @@ bool LoopVectorizePass::processLoop(Loop *L) {
     return false;
   }
 
+  if (LVL.hasSpeculativeEarlyExit()) {
+    LLVM_DEBUG(dbgs() << "LV: Not vectorizing: Auto-vectorization of early "
+                      << "exit loops is not yet supported.\n");
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paulwalker-arm wrote:

Is a `reportVectorizationFailure` required here until vectorisation is enabled?

https://github.com/llvm/llvm-project/pull/107004