[llvm] [RISCV] Preserve tail agnostic policy in some vector peepholes (PR #105788)

[Luke Lau via llvm-commits]

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@@ -498,10 +500,12 @@ bool RISCVVectorPeephole::foldVMV_V_V(MachineInstr &MI) {
                                               *Src->getParent()->getParent()));
   }
 
-  // Use a conservative tu,mu policy, RISCVInsertVSETVLI will relax it if
-  // passthru is undef.
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lukel97 wrote:

It still stands, but the passthru isn't undef in the new test so after RISCVInsertVSETVLI a tu policy gets emitted, even though the original policy was ta

https://github.com/llvm/llvm-project/pull/105788