[llvm] [AMDGPU] Fix bad removal of s_delay_alu (PR #145728)

[Jay Foad via llvm-commits]

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@@ -3070,6 +3070,7 @@ define amdgpu_kernel void @flat_atomic_inc_ret_i32_offset_addr64(ptr %out, ptr %
 ; GFX12-NEXT:    v_dual_mov_b32 v0, s0 :: v_dual_mov_b32 v1, s1
 ; GFX12-NEXT:    v_add_co_u32 v0, vcc_lo, v0, v2
 ; GFX12-NEXT:    s_wait_alu 0xfffd
+; GFX12-NEXT:    s_delay_alu instid0(VALU_DEP_2)
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jayfoad wrote:

Not your fault, but I think this delay is unnecessary because of the fast-forward path from add-with-carry-out to add-with-carry-in.

https://github.com/llvm/llvm-project/pull/145728