[llvm-branch-commits] [llvm] [X86] Remove extra MOV after widening atomic load (PR #148898)

[Simon Pilgrim via llvm-branch-commits]

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@@ -319,159 +319,60 @@ define <2 x i8> @atomic_vec2_i8(ptr %x) {
 define <2 x i16> @atomic_vec2_i16(ptr %x) {
 ; CHECK-O3-LABEL: atomic_vec2_i16:
 ; CHECK-O3:       # %bb.0:
-; CHECK-O3-NEXT:    movl (%rdi), %eax
-; CHECK-O3-NEXT:    movd %eax, %xmm0
+; CHECK-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
 ; CHECK-O3-NEXT:    retq
 ;
 ; CHECK-SSE-O3-LABEL: atomic_vec2_i16:
 ; CHECK-SSE-O3:       # %bb.0:
-; CHECK-SSE-O3-NEXT:    movl (%rdi), %eax
-; CHECK-SSE-O3-NEXT:    movd %eax, %xmm0
+; CHECK-SSE-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
 ; CHECK-SSE-O3-NEXT:    retq
 ;
 ; CHECK-AVX-O3-LABEL: atomic_vec2_i16:
 ; CHECK-AVX-O3:       # %bb.0:
-; CHECK-AVX-O3-NEXT:    movl (%rdi), %eax
-; CHECK-AVX-O3-NEXT:    vmovd %eax, %xmm0
+; CHECK-AVX-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
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RKSimon wrote:

in which case we have a problem - avx should be using vmovss

https://github.com/llvm/llvm-project/pull/148898