Module: Mesa Branch: master Commit: e38b93087638781ef83c9b3cc3bb424e448a5380 URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=e38b93087638781ef83c9b3cc3bb424e448a5380
Author: Timothy Arceri <[email protected]> Date: Fri Jun 28 10:10:28 2019 +1000 nir/lower_clip: add a find_clipvertex_and_position_outputs() helper This will allow code sharing in a following patch that adds support for lowering in geometry shaders. It also allows us to exit early if there is no lowering to do which allows a small code tidy up. Reviewed-by: Kenneth Graunke <[email protected]> --- src/compiler/nir/nir_lower_clip.c | 59 +++++++++++++++++++++++---------------- 1 file changed, 35 insertions(+), 24 deletions(-) diff --git a/src/compiler/nir/nir_lower_clip.c b/src/compiler/nir/nir_lower_clip.c index 474854d047b..1536f0a3451 100644 --- a/src/compiler/nir/nir_lower_clip.c +++ b/src/compiler/nir/nir_lower_clip.c @@ -146,6 +146,35 @@ find_output(nir_shader *shader, unsigned drvloc) return def; } +static bool +find_clipvertex_and_position_outputs(nir_shader *shader, + nir_variable **clipvertex, + nir_variable **position) +{ + nir_foreach_variable(var, &shader->outputs) { + switch (var->data.location) { + case VARYING_SLOT_POS: + *position = var; + break; + case VARYING_SLOT_CLIP_VERTEX: + *clipvertex = var; + break; + case VARYING_SLOT_CLIP_DIST0: + case VARYING_SLOT_CLIP_DIST1: + /* if shader is already writing CLIPDIST, then + * there should be no user-clip-planes to deal + * with. + * + * We assume nir_remove_dead_variables has removed the clipdist + * variables if they're not written. + */ + return false; + } + } + + return *clipvertex || *position; +} + /* * VS lowering */ @@ -185,27 +214,9 @@ nir_lower_clip_vs(nir_shader *shader, unsigned ucp_enables, bool use_vars) assert(impl->end_block->predecessors->entries == 1); b.cursor = nir_after_cf_list(&impl->body); - /* find clipvertex/position outputs: */ - nir_foreach_variable(var, &shader->outputs) { - switch (var->data.location) { - case VARYING_SLOT_POS: - position = var; - break; - case VARYING_SLOT_CLIP_VERTEX: - clipvertex = var; - break; - case VARYING_SLOT_CLIP_DIST0: - case VARYING_SLOT_CLIP_DIST1: - /* if shader is already writing CLIPDIST, then - * there should be no user-clip-planes to deal - * with. - * - * We assume nir_remove_dead_variables has removed the clipdist - * variables if they're not written. - */ - return false; - } - } + /* find clipvertex/position outputs */ + if (!find_clipvertex_and_position_outputs(shader, &clipvertex, &position)) + return false; if (use_vars) { cv = nir_load_var(&b, clipvertex ? clipvertex : position); @@ -218,10 +229,10 @@ nir_lower_clip_vs(nir_shader *shader, unsigned ucp_enables, bool use_vars) } else { if (clipvertex) cv = find_output(shader, clipvertex->data.driver_location); - else if (position) + else { + assert(position); cv = find_output(shader, position->data.driver_location); - else - return false; + } } /* insert CLIPDIST outputs: */ _______________________________________________ mesa-commit mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/mesa-commit
