[llvm-branch-commits] [llvm] [X86] Manage atomic load of fp -> int promotion in DAG (PR #120386)

[Matt Arsenault via llvm-branch-commits]

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@@ -145,3 +145,40 @@ define <1 x i64> @atomic_vec1_i64_align(ptr %x) nounwind {
   %ret = load atomic <1 x i64>, ptr %x acquire, align 8
   ret <1 x i64> %ret
 }
+
+define <1 x half> @atomic_vec1_half(ptr %x) {
+; CHECK3-LABEL: atomic_vec1_half:
+; CHECK3:       ## %bb.0:
+; CHECK3-NEXT:    movzwl (%rdi), %eax
+; CHECK3-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK3-NEXT:    retq
+;
+; CHECK0-LABEL: atomic_vec1_half:
+; CHECK0:       ## %bb.0:
+; CHECK0-NEXT:    movw (%rdi), %cx
+; CHECK0-NEXT:    ## implicit-def: $eax
+; CHECK0-NEXT:    movw %cx, %ax
+; CHECK0-NEXT:    ## implicit-def: $xmm0
+; CHECK0-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK0-NEXT:    retq
+  %ret = load atomic <1 x half>, ptr %x acquire, align 4
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arsenm wrote:

```suggestion
  %ret = load atomic <1 x half>, ptr %x acquire, align 2
```

https://github.com/llvm/llvm-project/pull/120386