arch-vega: Implement non-carry-out VEGA add, sub, and subrev
In GCN3, the v_add_u32, v_sub_u32, and v_subrev_u32 instructions write
the carry-out value to VCC. VEGA introduces explicit carry-out versions
of these instructions (v_add_co_u32, v_sub_co_u32, and v_subrev_co_u32),
and modifies the behavior of the baseline, non-carry-out versions to not
write to VCC. Previously both the carry-out and non-carry-out versions
shared a single implementation that wrote to VCC. This patch correctly
implements the non-carry-out versions to avoid the VCC write.
This patch also makes the following substitutions for GCN3 instructions
that no longer exist in VEGA (this renaming has no functional impact):
v_addc_u32 -> v_addc_co_u32
v_subb_u32 -> v_subb_co_u32
v_subbrev_u32 -> v_subbrev_co_u32
Change-Id: I002fa6e9316d38fd4cc3554daff047523cfc12c9
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47240
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
4 files changed
