[llvm] [LoopVectorize] Enable more early exit vectorisation tests (PR #117008)

[David Sherwood via llvm-commits]

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@@ -10177,13 +10202,33 @@ bool LoopVectorizePass::processLoop(Loop *L) {
     return false;
   }
 
-  if (LVL.hasUncountableEarlyExit() && !EnableEarlyExitVectorization) {
-    reportVectorizationFailure("Auto-vectorization of loops with uncountable "
-                               "early exit is not enabled",
-                               "Auto-vectorization of loops with uncountable "
-                               "early exit is not enabled",
-                               "UncountableEarlyExitLoopsDisabled", ORE, L);
-    return false;
+  if (LVL.hasUncountableEarlyExit()) {
+    if (!EnableEarlyExitVectorization) {
+      reportVectorizationFailure("Auto-vectorization of loops with uncountable "
+                                 "early exit is not enabled",
+                                 "Auto-vectorization of loops with uncountable "
+                                 "early exit is not enabled",
+                                 "UncountableEarlyExitLoopsDisabled", ORE, L);
+      return false;
+    }
+
+    // Needed to prevent InnerLoopVectorizer::fixupIVUsers from crashing.
+    for (BasicBlock *BB : L->blocks()) {
+      for (Instruction &I : *BB) {
+        for (User *U : I.users()) {
+          Instruction *UI = cast<Instruction>(U);
+          if (!L->contains(UI)) {
+            reportVectorizationFailure(
+                "Auto-vectorization of loops with uncountable "
+                "early exit and live-outs is not yet supported",
+                "Auto-vectorization of loop with uncountable "
+                "early exit and live-outs is not yet supported",
----------------
david-arm wrote:

Good suggestion! I've added one and I've started using it in this patch, but as a follow-on I'm happy to clean up any other cases in the vectoriser or legality code that take duplicated strings.

https://github.com/llvm/llvm-project/pull/117008