[llvm] [AMDGPU] canCreateUndefOrPoisonForTargetNode - BFE_I32/U32 can't create poison/undef (PR #154932)

[Matt Arsenault via llvm-commits]

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@@ -76,12 +76,13 @@ define amdgpu_kernel void @v_round_f64(ptr addrspace(1) %out, ptr addrspace(1) %
 ; SI-NEXT:    s_waitcnt lgkmcnt(0)
 ; SI-NEXT:    s_mov_b64 s[4:5], s[2:3]
 ; SI-NEXT:    buffer_load_dwordx2 v[2:3], v[0:1], s[4:7], 0 addr64
+; SI-NEXT:    s_movk_i32 s4, 0xfc01
 ; SI-NEXT:    s_mov_b32 s2, -1
 ; SI-NEXT:    s_mov_b32 s3, 0xfffff
 ; SI-NEXT:    v_mov_b32_e32 v8, 0x3ff00000
 ; SI-NEXT:    s_waitcnt vmcnt(0)
 ; SI-NEXT:    v_bfe_u32 v4, v3, 20, 11
-; SI-NEXT:    v_add_i32_e32 v6, vcc, 0xfffffc01, v4
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arsenm wrote:

I don't know how anything you do in the DAG would cause this regression 

https://github.com/llvm/llvm-project/pull/154932