[llvm] [clang] [clang-tools-extra] [X86] Use plain load/store instead of cmpxchg16b for atomics with AVX (PR #74275)

[Philip Reames via cfe-commits]

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@@ -228,87 +228,86 @@ define void @widen_broadcast_unaligned(ptr %p0, i32 %v) {
 }
 
 define i128 @load_i128(ptr %ptr) {
-; CHECK-O0-LABEL: load_i128:
-; CHECK-O0:       # %bb.0:
-; CHECK-O0-NEXT:    pushq %rbx
-; CHECK-O0-NEXT:    .cfi_def_cfa_offset 16
-; CHECK-O0-NEXT:    .cfi_offset %rbx, -16
-; CHECK-O0-NEXT:    xorl %eax, %eax
-; CHECK-O0-NEXT:    movl %eax, %ebx
-; CHECK-O0-NEXT:    movq %rbx, %rax
-; CHECK-O0-NEXT:    movq %rbx, %rdx
-; CHECK-O0-NEXT:    movq %rbx, %rcx
-; CHECK-O0-NEXT:    lock cmpxchg16b (%rdi)
-; CHECK-O0-NEXT:    popq %rbx
-; CHECK-O0-NEXT:    .cfi_def_cfa_offset 8
-; CHECK-O0-NEXT:    retq
-;
-; CHECK-O3-LABEL: load_i128:
-; CHECK-O3:       # %bb.0:
-; CHECK-O3-NEXT:    pushq %rbx
-; CHECK-O3-NEXT:    .cfi_def_cfa_offset 16
-; CHECK-O3-NEXT:    .cfi_offset %rbx, -16
-; CHECK-O3-NEXT:    xorl %eax, %eax
-; CHECK-O3-NEXT:    xorl %edx, %edx
-; CHECK-O3-NEXT:    xorl %ecx, %ecx
-; CHECK-O3-NEXT:    xorl %ebx, %ebx
-; CHECK-O3-NEXT:    lock cmpxchg16b (%rdi)
-; CHECK-O3-NEXT:    popq %rbx
-; CHECK-O3-NEXT:    .cfi_def_cfa_offset 8
-; CHECK-O3-NEXT:    retq
+; CHECK-O0-CUR-LABEL: load_i128:
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preames wrote:

Your tests need updated, these check prefixes no longer exist.  

https://github.com/llvm/llvm-project/pull/74275