[llvm] [LoopVectorize] Add support for vectorisation of more early exit loops (PR #88385)

[Graham Hunter via llvm-commits]

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@@ -8604,6 +8604,24 @@ ScalarEvolution::BackedgeTakenInfo::getExact(const Loop *L, ScalarEvolution *SE,
   return SE->getUMinFromMismatchedTypes(Ops, /* Sequential */ true);
 }
 
+void ScalarEvolution::BackedgeTakenInfo::getCountableExitingBlocks(
+    const Loop *L, ScalarEvolution *SE,
+    SmallVector<BasicBlock *, 4> *Blocks) const {
+  // All exiting blocks we have collected must dominate the only backedge.
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huntergr-arm wrote:

How is this dominance requirement checked?

https://github.com/llvm/llvm-project/pull/88385