[llvm] [VPlan] Recognise single-scalar VPInstructions in isUniformAcrossVFsAndUFs (PR #194674)

[Florian Hahn via llvm-commits]

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@@ -429,7 +429,8 @@ bool vputils::isUniformAcrossVFsAndUFs(VPValue *V) {
                all_of(R->operands(), isUniformAcrossVFsAndUFs);
       })
       .Case([](const VPInstruction *VPI) {
-        return preservesUniformity(VPI->getOpcode()) &&
+        return (VPI->isSingleScalar() || VPI->isVectorToScalar() ||
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fhahn wrote:

would be good to add a test for a isVectorToScalar, and also for isSingleScalar with operands

https://github.com/llvm/llvm-project/pull/194674