[llvm] [RISCV] Set a barrier between mask producer and user of V0 (PR #114012)

[Pengcheng Wang via llvm-commits]

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@@ -15,25 +15,25 @@ define <2 x half> @vfmax_v2f16_vv(<2 x half> %a, <2 x half> %b) {
 ; ZVFH:       # %bb.0:
 ; ZVFH-NEXT:    vsetivli zero, 2, e16, mf4, ta, ma
 ; ZVFH-NEXT:    vmfeq.vv v0, v8, v8
-; ZVFH-NEXT:    vmfeq.vv v10, v9, v9
-; ZVFH-NEXT:    vmerge.vvm v11, v8, v9, v0
-; ZVFH-NEXT:    vmv1r.v v0, v10
+; ZVFH-NEXT:    vmerge.vvm v10, v8, v9, v0
+; ZVFH-NEXT:    vmfeq.vv v0, v9, v9
 ; ZVFH-NEXT:    vmerge.vvm v8, v9, v8, v0
-; ZVFH-NEXT:    vfmax.vv v8, v8, v11
+; ZVFH-NEXT:    vfmax.vv v8, v8, v10
 ; ZVFH-NEXT:    ret
 ;
 ; ZVFHMIN-LABEL: vfmax_v2f16_vv:
 ; ZVFHMIN:       # %bb.0:
 ; ZVFHMIN-NEXT:    vsetivli zero, 2, e16, mf4, ta, ma
-; ZVFHMIN-NEXT:    vfwcvt.f.f.v v10, v9
-; ZVFHMIN-NEXT:    vfwcvt.f.f.v v9, v8
+; ZVFHMIN-NEXT:    vfwcvt.f.f.v v10, v8
 ; ZVFHMIN-NEXT:    vsetvli zero, zero, e32, mf2, ta, ma
-; ZVFHMIN-NEXT:    vmfeq.vv v0, v9, v9
-; ZVFHMIN-NEXT:    vmfeq.vv v8, v10, v10
-; ZVFHMIN-NEXT:    vmerge.vvm v11, v9, v10, v0
-; ZVFHMIN-NEXT:    vmv1r.v v0, v8
-; ZVFHMIN-NEXT:    vmerge.vvm v8, v10, v9, v0
-; ZVFHMIN-NEXT:    vfmax.vv v9, v8, v11
+; ZVFHMIN-NEXT:    vmfeq.vv v0, v10, v10
+; ZVFHMIN-NEXT:    vsetvli zero, zero, e16, mf4, ta, ma
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wangpc-pp wrote:

An example that causes more vtype toggles.

https://github.com/llvm/llvm-project/pull/114012