[llvm] [VPlan] Change parent of VPReductionRecipe to VPRecipeWithIRFlags. NFC (PR #130881)

[Florian Hahn via llvm-commits]

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@@ -788,6 +790,12 @@ class VPRecipeWithIRFlags : public VPSingleDefRecipe {
     }
   }
 
+  /// Set fast-math flags for this recipe.
+  void setFastMathFlags(FastMathFlags FMFs) {
+    assert(OpType == OperationType::FPMathOp);
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fhahn wrote:

Please add a message to the assert

https://github.com/llvm/llvm-project/pull/130881