[llvm] [NFC] get rid of `undef` in avx512vl-intrinsics.ll test (PR #143641)

[Craig Topper via llvm-commits]

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@@ -6861,7 +6877,7 @@ define <4 x float> @test_mask_vfmadd128_ps_rmb(<4 x float> %a0, <4 x float> %a1,
 ; X64-NEXT:    # xmm0 {%k1} = (xmm1 * xmm0) + mem
 ; X64-NEXT:    retq # encoding: [0xc3]
   %q = load float, ptr %ptr_a2
-  %vecinit.i = insertelement <4 x float> undef, float %q, i32 0
+  %vecinit.i = insertelement <4 x float> %orig, float %q, i32 0
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topperc wrote:

You can use poison here. It's going to be overwritten. that should be what InstCombine would turn it into.

https://github.com/llvm/llvm-project/pull/143641