[llvm] [RISCV] Handle scalable ops with < EEW / 2 narrow types in combineBinOp_VLToVWBinOp_VL (PR #84158)

[via llvm-commits]

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@@ -1367,13 +1367,27 @@ define <vscale x 8 x i64> @vwaddu_wx_nxv8i64_nxv8i8(<vscale x 8 x i64> %va, i8 %
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    vsetvli a1, zero, e8, m1, ta, ma
 ; CHECK-NEXT:    vmv.v.x v16, a0
-; CHECK-NEXT:    vsetvli zero, zero, e64, m8, ta, ma
-; CHECK-NEXT:    vzext.vf8 v24, v16
-; CHECK-NEXT:    vadd.vv v8, v8, v24
+; CHECK-NEXT:    vsetvli zero, zero, e32, m4, ta, ma
+; CHECK-NEXT:    vzext.vf4 v20, v16
+; CHECK-NEXT:    vwaddu.wv v8, v8, v20
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i8> poison, i8 %b, i8 0
   %splat = shufflevector <vscale x 8 x i8> %head, <vscale x 8 x i8> poison, <vscale x 8 x i32> zeroinitializer
   %vb = zext <vscale x 8 x i8> %splat to <vscale x 8 x i64>
   %vc = add <vscale x 8 x i64> %va, %vb
   ret <vscale x 8 x i64> %vc
 }
+
+; Make sure that we don't introduce any V{S,Z}EXT_VL nodes with i1 types from
+; combineBinOp_VLToVWBinOp_VL, since they can't be selected.
+define <vscale x 1 x i64> @foo(<vscale x 1 x i1> %va, <vscale x 1 x i64> %vb, ptr %p) {
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sun-jacobi wrote:

Is this name on purpose?

https://github.com/llvm/llvm-project/pull/84158