[llvm] [SelectionDAG] Make `(a & x) | (~a & y) -> (a & (x ^ y)) ^ y` available for all targets (PR #137641)

[Iris Shi via llvm-commits]

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@@ -28,9 +28,9 @@ define amdgpu_kernel void @s_bfi_def_i32(ptr addrspace(1) %out, i32 %x, i32 %y,
 ; GFX8-NEXT:    s_load_dwordx4 s[0:3], s[4:5], 0x2c
 ; GFX8-NEXT:    s_load_dwordx2 s[4:5], s[4:5], 0x24
 ; GFX8-NEXT:    s_waitcnt lgkmcnt(0)
-; GFX8-NEXT:    s_andn2_b32 s2, s2, s0
+; GFX8-NEXT:    s_xor_b32 s1, s1, s2
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el-ev wrote:

I believe that's because those subtargets don't correctly report them having AndNot instructions.

https://github.com/llvm/llvm-project/pull/137641