[llvm] [RISCV] AddEdge between first mask producer and user of V0 (PR #146855)

[Min-Yih Hsu via llvm-commits]

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@@ -493,33 +487,31 @@ define <vscale x 2 x i8> @vwop_vscale_zext_i1i8_multiple_users(ptr %x, ptr %y, p
 ; NO_FOLDING-NEXT:    vsetvli a3, zero, e8, mf4, ta, mu
 ; NO_FOLDING-NEXT:    vlm.v v0, (a0)
 ; NO_FOLDING-NEXT:    vlm.v v8, (a2)
-; NO_FOLDING-NEXT:    vlm.v v9, (a1)
-; NO_FOLDING-NEXT:    vmv.v.i v10, 0
-; NO_FOLDING-NEXT:    vmerge.vim v11, v10, 1, v0
+; NO_FOLDING-NEXT:    vmv.v.i v9, 0
+; NO_FOLDING-NEXT:    vmerge.vim v10, v9, 1, v0
 ; NO_FOLDING-NEXT:    vmv1r.v v0, v8
-; NO_FOLDING-NEXT:    vmerge.vim v8, v10, 1, v0
-; NO_FOLDING-NEXT:    vadd.vv v10, v11, v8
-; NO_FOLDING-NEXT:    vsub.vv v8, v11, v8
-; NO_FOLDING-NEXT:    vmv1r.v v0, v9
-; NO_FOLDING-NEXT:    vor.vv v10, v10, v11, v0.t
-; NO_FOLDING-NEXT:    vor.vv v8, v10, v8
+; NO_FOLDING-NEXT:    vmerge.vim v8, v9, 1, v0
+; NO_FOLDING-NEXT:    vlm.v v0, (a1)
+; NO_FOLDING-NEXT:    vadd.vv v9, v10, v8
+; NO_FOLDING-NEXT:    vsub.vv v8, v10, v8
+; NO_FOLDING-NEXT:    vor.vv v9, v9, v10, v0.t
+; NO_FOLDING-NEXT:    vor.vv v8, v9, v8
 ; NO_FOLDING-NEXT:    ret
 ;
 ; FOLDING-LABEL: vwop_vscale_zext_i1i8_multiple_users:
 ; FOLDING:       # %bb.0:
 ; FOLDING-NEXT:    vsetvli a3, zero, e8, mf4, ta, mu
 ; FOLDING-NEXT:    vlm.v v0, (a0)
 ; FOLDING-NEXT:    vlm.v v8, (a2)
-; FOLDING-NEXT:    vlm.v v9, (a1)
-; FOLDING-NEXT:    vmv.v.i v10, 0
-; FOLDING-NEXT:    vmerge.vim v11, v10, 1, v0
+; FOLDING-NEXT:    vmv.v.i v9, 0
+; FOLDING-NEXT:    vmerge.vim v10, v9, 1, v0
 ; FOLDING-NEXT:    vmv1r.v v0, v8
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mshockwave wrote:

do we know if we could eliminate this as well? namely moving vlm.v from `a2` closer to vmerge.vim below.

https://github.com/llvm/llvm-project/pull/146855