[llvm] [RISCV] Combine (vp.splice (insert_elt poison, scalar, 0), vec, 0, mask, 1, vl) to vslide1up. (PR #144871)

[Pengcheng Wang via llvm-commits]

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@@ -286,3 +286,27 @@ define <vscale x 2 x float> @test_vp_splice_nxv2f32_masked(<vscale x 2 x float>
   %v = call <vscale x 2 x float> @llvm.experimental.vp.splice.nxv2f32(<vscale x 2 x float> %va, <vscale x 2 x float> %vb, i32 5, <vscale x 2 x i1> %mask, i32 %evla, i32 %evlb)
   ret <vscale x 2 x float> %v
 }
+
+define <vscale x 2 x i32> @test_vp_splice_nxv2i32_with_firstelt(i32 %first, <vscale x 2 x i32> %vb, <vscale x 2 x i1> %mask, i32 zeroext %evl) {
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wangpc-pp wrote:

precommit test?

https://github.com/llvm/llvm-project/pull/144871