[llvm] [RISCV] Move RISCVInsertVSETVLI to after phi elimination (PR #91440)

[Philip Reames via llvm-commits]

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@@ -811,11 +811,11 @@ define <4 x i32> @ustest_f16i32(<4 x half> %x) {
 ; CHECK-V-NEXT:    addi a0, sp, 16
 ; CHECK-V-NEXT:    vl1r.v v9, (a0) # Unknown-size Folded Reload
 ; CHECK-V-NEXT:    vslideup.vi v8, v9, 1
-; CHECK-V-NEXT:    vsetivli zero, 4, e64, m2, ta, ma
 ; CHECK-V-NEXT:    csrr a0, vlenb
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preames wrote:

This diff doesn't matter, but is another instance where moving the vsetvli maximally backward would remove a test diff.  

https://github.com/llvm/llvm-project/pull/91440