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

[Luke Lau via llvm-commits]

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@@ -15,7 +15,7 @@ body: |
     ; CHECK-NEXT: %avl:gprnox0 = COPY $x1
     ; CHECK-NEXT: %mask:vmv0 = PseudoVMSET_M_B8 %avl, 5 /* e32 */
     ; CHECK-NEXT: $v0 = COPY %mask
-    ; CHECK-NEXT: %x:vr = PseudoVMV_V_V_M1 %false, %true, %avl, 5 /* e32 */, 0 /* tu, mu */
+    ; CHECK-NEXT: %x:vr = PseudoVMV_V_V_M1 %false, %true, %avl, 5 /* e32 */, 1 /* ta, mu */
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lukel97 wrote:

I don't think we need to since elements, I think we can just use the passthru given that all the elements come from true or the tail (passthru). I think this is just a detail from the initial implementation in https://reviews.llvm.org/D133255

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