[llvm] [RISCV] Select mask operands as virtual registers and eliminate vmv0 (PR #125026)

[Luke Lau via llvm-commits]

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@@ -5,13 +5,14 @@
 define i8 @extract_last_i8(<16 x i8> %data, <16 x i8> %mask, i8 %passthru) {
 ; CHECK-LABEL: extract_last_i8:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetivli zero, 16, e8, m1, ta, mu
+; CHECK-NEXT:    vsetivli zero, 16, e8, m1, ta, ma
 ; CHECK-NEXT:    vmsne.vi v0, v9, 0
-; CHECK-NEXT:    vmv.v.i v9, 0
 ; CHECK-NEXT:    vcpop.m a1, v0
-; CHECK-NEXT:    vid.v v9, v0.t
 ; CHECK-NEXT:    beqz a1, .LBB0_2
 ; CHECK-NEXT:  # %bb.1:
+; CHECK-NEXT:    vmv.v.i v9, 0
+; CHECK-NEXT:    vsetvli zero, zero, e8, m1, ta, mu
+; CHECK-NEXT:    vid.v v9, v0.t
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lukel97 wrote:

This is an example of code sinking

https://github.com/llvm/llvm-project/pull/125026