[llvm] [RISCV] Don't set AVL if only zeroness is demanded (PR #74049)

[Philip Reames via llvm-commits]

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@@ -1086,6 +1095,14 @@ void RISCVInsertVSETVLI::transferBefore(VSETVLIInfo &Info,
           IncomingInfo.getTailAgnostic(),
       (Demanded.MaskPolicy ? IncomingInfo : Info).getMaskAgnostic() ||
           IncomingInfo.getMaskAgnostic());
+
+  // If we only knew the sew/lmul ratio previously, replace the VTYPE but keep
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preames wrote:

Is there any value having this here as opposed to as an early exit before we call adjustIncoming?  

https://github.com/llvm/llvm-project/pull/74049