[llvm] [LV]Support dropping of nneg flag for zext widencast recipes. (PR #74112)

[Florian Hahn via llvm-commits]

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@@ -652,6 +652,10 @@ void VPRecipeWithIRFlags::printFlags(raw_ostream &O) const {
     if (GEPFlags.IsInBounds)
       O << " inbounds";
     break;
+  case OperationType::CastOp:
+    if (CastFlags.NonNeg)
+      O << " nneg";
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fhahn wrote:

Can you add a test for printing the flag to `llvm/test/Transforms/LoopVectorize/vplan-printing.ll`?

https://github.com/llvm/llvm-project/pull/74112