[llvm] [RISCV] Adjust LMUL if not used to avoid VL toggle (PR #69259)

[Philip Reames via llvm-commits]

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@@ -65,9 +65,8 @@ define <32 x i32> @insertelt_v32i32_31(<32 x i32> %a, i32 %y) {
 ; CHECK-LABEL: insertelt_v32i32_31:
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    li a1, 32
-; CHECK-NEXT:    vsetvli zero, a1, e32, m1, ta, ma
-; CHECK-NEXT:    vmv.s.x v16, a0
 ; CHECK-NEXT:    vsetvli zero, a1, e32, m8, ta, ma
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preames wrote:

This is an interesting sub-case as we shouldn't need to be reasoning about ratios here.  Why didn't the existing logic get this case given only LMUL is changing?  I think this might just be the lack of LI handling in isNonZeroAVL?  

https://github.com/llvm/llvm-project/pull/69259