[clang] [llvm] [clang-tools-extra] [VPlan] Add new VPUniformPerUFRecipe, use for step truncation. (PR #78113)

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@@ -164,6 +164,8 @@ bool VPRecipeBase::mayHaveSideEffects() const {
     auto *R = cast<VPReplicateRecipe>(this);
     return R->getUnderlyingInstr()->mayHaveSideEffects();
   }
+  case VPScalarCastSC:
+    return false;
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ayalz wrote:

nit: join the above group known to return false including VPDerivedIVSC and VPPredInstPHISC?

https://github.com/llvm/llvm-project/pull/78113