[llvm] [AMDGPU] Add new aliases ds_subrev_rtn_u32/u64 for ds_rsub_rtn_u32/u64 (PR #83408)

[Matt Arsenault via llvm-commits]

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@@ -27,5 +27,11 @@ ds_min_rtn_f64 v[5:6], v1, v[2:3]
 ds_subrev_u32 v1, v2
 // GFX12: ds_rsub_u32 v1, v2                      ; encoding: [0x00,0x00,0x08,0xd8,0x01,0x02,0x00,0x00]
 
+ds_subrev_rtn_u32 v5, v1, v2
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arsenm wrote:

do we need tests that the alias is rejected on other targets?

https://github.com/llvm/llvm-project/pull/83408