[llvm] [WIP][X86] lowerBuildVectorAsBroadcast - don't convert constant vectors to broadcasts on AVX512VL targets (PR #73509)

[Simon Pilgrim via llvm-commits]

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@@ -8,7 +8,7 @@ define <4 x float> @test_int_x86_avx512fp8_mask_cfmadd_ph_bst(<4 x float> %x0, <
 ; CHECK-LABEL: test_int_x86_avx512fp8_mask_cfmadd_ph_bst:
 ; CHECK:       ## %bb.0:
 ; CHECK-NEXT:    kmovd %edi, %k1
-; CHECK-NEXT:    vfmaddcph {{\.?LCPI[0-9]+_[0-9]+}}(%rip){1to4}, %xmm0, %xmm1 {%k1}
+; CHECK-NEXT:    vfmaddcph {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm0, %xmm1 {%k1}
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RKSimon wrote:

This is an example of what I meant when asking whether I should be waiting on #66360 or just manually extending the broadcast tables

https://github.com/llvm/llvm-project/pull/73509