[llvm] [X86] Avoid zero extend i16 when inserting fp16 (PR #126194)

[Simon Pilgrim via llvm-commits]

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@@ -43,15 +43,15 @@ define void @v_test_canonicalize__half(half addrspace(1)* %out) nounwind {
 ;
 ; AVX512-LABEL: v_test_canonicalize__half:
 ; AVX512:       # %bb.0: # %entry
-; AVX512-NEXT:    movzwl (%rdi), %eax
-; AVX512-NEXT:    movzwl {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %ecx
-; AVX512-NEXT:    vmovd %ecx, %xmm0
-; AVX512-NEXT:    vcvtph2ps %xmm0, %xmm0
-; AVX512-NEXT:    vmovd %eax, %xmm1
+; AVX512-NEXT:    vpinsrw $0, (%rdi), %xmm0, %xmm0
+; AVX512-NEXT:    vpinsrw $0, {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm0, %xmm1
+; AVX512-NEXT:    vpxor %xmm2, %xmm2, %xmm2
+; AVX512-NEXT:    vpblendw {{.*#+}} xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
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RKSimon wrote:

This is not zeroing out v8i16[1] element anymore? Just v8i16[2-7].

https://github.com/llvm/llvm-project/pull/126194