[llvm] [AMDGPU] Add new 64-bit SALU instructions (PR #74449)

[Jay Foad via llvm-commits]

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@@ -2072,6 +2086,9 @@ defm S_MUL_HI_I32      : SOP2_Real_gfx11_gfx12<0x02e>;
 defm S_CSELECT_B32     : SOP2_Real_gfx11_gfx12<0x030>;
 defm S_CSELECT_B64     : SOP2_Real_gfx11_gfx12<0x031>;
 defm S_PACK_HL_B32_B16 : SOP2_Real_gfx11_gfx12<0x035>;
+defm S_ADD_NC_U64      : SOP2_Real_Renamed_gfx12<0x053, S_ADD_U64, "s_add_nc_u64">;
+defm S_SUB_NC_U64      : SOP2_Real_Renamed_gfx12<0x054, S_SUB_U64, "s_sub_nc_u64">;
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jayfoad wrote:

To be clear, GFX12 is adding "NC" to the SALU name to match the VALU equivalents. The old versions without NC (like S_ADD_U64) are still accepted for compatibility.

https://github.com/llvm/llvm-project/pull/74449