[llvm] [LV][VPlan] set FastMathFlags on EVLRecipe (PR #119847)

[Luke Lau via llvm-commits]

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@@ -1516,16 +1516,23 @@ static void transformRecipestoEVLRecipes(VPlan &Plan, VPValue &EVL) {
                         IntegerType::getInt1Ty(CI->getContext())));
                     Ops.push_back(Mask);
                     Ops.push_back(&EVL);
+                    FastMathFlags FMF = {};
+                    if (isa<FPMathOperator>(CI))
+                      FMF = CI->getFastMathFlags();
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lukel97 wrote:

FastMathFlags on cast instructions seems to be a new thing? https://github.com/llvm/llvm-project/pull/115894

In that case should we preserve them in VPWidenCastRecipe/VPScalarCastRecipe first? I can't find anything there that preserves them

https://github.com/llvm/llvm-project/pull/119847