[llvm] [LV] Avoid crashing for vector calls with scalar byte types (PR #197417)

[Graham Hunter via llvm-commits]

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@@ -5026,7 +5027,8 @@ void LoopVectorizationCostModel::setVectorizedCallDecision(ElementCount VF) {
             // TODO: do we need to figure out the cost of an extract to get the
             // first lane? Or do we hope that it will be folded away?
             ScalarEvolution *SE = PSE.getSE();
-            if (!match(SE->getSCEV(ScalarParam),
+            if (!SE->isSCEVable(ScalarParam->getType()) ||
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huntergr-arm wrote:

Yep, the test file hits an assert without those changes.

https://github.com/llvm/llvm-project/pull/197417