[llvm] [LV] Bail out if loop nest contains non-widenable types. (PR #226463)

[Florian Hahn via llvm-commits]

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@@ -623,6 +639,23 @@ bool LoopVectorizationLegality::canVectorizeOuterLoop() {
   bool DoExtraAnalysis = ORE->allowExtraAnalysis(DEBUG_TYPE);
 
   for (BasicBlock *BB : TheLoop->blocks()) {
+    // Instructions in the loop nest are widened, so the types they produce and
+    // store must be widenable. Struct-returning calls are not supported yet.
+    for (Instruction &I : *BB) {
+      auto *SI = dyn_cast<StoreInst>(&I);
+      if (canWidenResultType(I, /*AllowStructCalls=*/false) &&
+          (!SI ||
+           VectorType::isValidElementType(SI->getValueOperand()->getType())))
+        continue;
+      reportVectorizationFailure("Found unvectorizable type",
+                                 "instruction type cannot be vectorized",
+                                 "CantVectorizeInstructionType", ORE, TheLoop,
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fhahn wrote:

Thanks, I updated the code to share the logic to emit the remarks as well in both inner and outer loop paths

https://github.com/llvm/llvm-project/pull/226463