Module: Mesa Branch: main Commit: 052d12492dc7687732d56da17e9cd014925a53f7 URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=052d12492dc7687732d56da17e9cd014925a53f7
Author: Samuel Pitoiset <[email protected]> Date: Mon Oct 9 13:50:57 2023 +0200 ac/nir: only consider overflow for valid feedback buffers Otherwise the ordered operation above (ie. a GDS atomic return) might return non-zero offsets for invalid buffers. Fixes: f7076d129db ("amd: add nir_intrinsic_xfb_counter_sub_amd and fix overflowed streamout offsets") Signed-off-by: Samuel Pitoiset <[email protected]> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25613> --- src/amd/common/ac_nir_lower_ngg.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/amd/common/ac_nir_lower_ngg.c b/src/amd/common/ac_nir_lower_ngg.c index 0872c1e2f15..72fcb9c9b66 100644 --- a/src/amd/common/ac_nir_lower_ngg.c +++ b/src/amd/common/ac_nir_lower_ngg.c @@ -1893,7 +1893,15 @@ ngg_build_streamout_buffer_info(nir_builder *b, continue; nir_def *buffer_size = nir_channel(b, so_buffer_ret[buffer], 2); + + /* Only consider overflow for valid feedback buffers because + * otherwise the ordered operation above (GDS atomic return) might + * return non-zero offsets for invalid buffers. + */ + nir_def *buffer_valid = nir_ine_imm(b, buffer_size, 0); nir_def *buffer_offset = nir_channel(b, buffer_offsets, buffer); + buffer_offset = nir_bcsel(b, buffer_valid, buffer_offset, nir_imm_int(b, 0)); + nir_def *remain_size = nir_isub(b, buffer_size, buffer_offset); nir_def *remain_prim = nir_idiv(b, remain_size, prim_stride_ret[buffer]); nir_def *overflow = nir_ilt(b, buffer_size, buffer_offset);
