From 4e69fba534e7377f3bc6c40c73e6bc5c23437d4e Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Wed, 13 Feb 2019 16:15:42 -0600 Subject: [PATCH] nir: Rewrite lower_clip_cull_distance_arrays to do a lot less lowering MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Instead of going to all the work of to combine them into one array, just make two arrays and use location_frac to colocate them within CLIP0. Then the back-end can sort things out and stack them on top of each other. Thanks to ef99f4c8, we also don't need to set compact anymore. Reviewed-by: Alejandro Piñeiro Reviewed-by: Kenneth Graunke --- .../nir/nir_lower_clip_cull_distance_arrays.c | 132 +++--------------- 1 file changed, 19 insertions(+), 113 deletions(-) diff --git a/src/compiler/nir/nir_lower_clip_cull_distance_arrays.c b/src/compiler/nir/nir_lower_clip_cull_distance_arrays.c index 05cd6af2195..d98ffa69596 100644 --- a/src/compiler/nir/nir_lower_clip_cull_distance_arrays.c +++ b/src/compiler/nir/nir_lower_clip_cull_distance_arrays.c @@ -27,10 +27,10 @@ /** * @file * - * This pass combines separate clip and cull distance arrays into a - * single array that contains both. Clip distances come first, then - * cull distances. It also populates nir_shader_info with the size - * of the original arrays so the driver knows which are which. + * This pass combines clip and cull distance arrays in separate locations and + * colocates them both in VARYING_SLOT_CLIP_DIST0. It does so by maintaining + * two arrays but making them compact and using location_frac to stack them on + * top of each other. */ /** @@ -56,77 +56,6 @@ get_unwrapped_array_length(nir_shader *nir, nir_variable *var) return glsl_get_length(type); } -/** - * Update the type of the combined array (including interface block nesting). - */ -static void -update_type(nir_variable *var, gl_shader_stage stage, unsigned length) -{ - const struct glsl_type *type = glsl_array_type(glsl_float_type(), length, 0); - - if (nir_is_per_vertex_io(var, stage)) - type = glsl_array_type(type, glsl_get_length(var->type), 0); - - var->type = type; -} - -static void -rewrite_clip_cull_deref(nir_builder *b, - nir_deref_instr *deref, - const struct glsl_type *type, - unsigned tail_offset) -{ - deref->type = type; - - if (glsl_type_is_array(type)) { - const struct glsl_type *child_type = glsl_get_array_element(type); - nir_foreach_use(src, &deref->dest.ssa) { - rewrite_clip_cull_deref(b, nir_instr_as_deref(src->parent_instr), - child_type, tail_offset); - } - } else { - assert(glsl_type_is_scalar(type)); - - /* This is the end of the line. Add the tail offset if needed */ - if (tail_offset > 0) { - b->cursor = nir_before_instr(&deref->instr); - assert(deref->deref_type == nir_deref_type_array); - nir_ssa_def *index = nir_iadd(b, deref->arr.index.ssa, - nir_imm_int(b, tail_offset)); - nir_instr_rewrite_src(&deref->instr, &deref->arr.index, - nir_src_for_ssa(index)); - } - } -} - -static void -rewrite_references(nir_builder *b, - nir_instr *instr, - nir_variable *combined, - unsigned cull_offset) -{ - if (instr->type != nir_instr_type_deref) - return; - - nir_deref_instr *deref = nir_instr_as_deref(instr); - if (deref->deref_type != nir_deref_type_var) - return; - - if (deref->var->data.mode != combined->data.mode) - return; - - const unsigned location = deref->var->data.location; - if (location != VARYING_SLOT_CLIP_DIST0 && - location != VARYING_SLOT_CULL_DIST0) - return; - - deref->var = combined; - if (location == VARYING_SLOT_CULL_DIST0) - rewrite_clip_cull_deref(b, deref, combined->type, cull_offset); - else - rewrite_clip_cull_deref(b, deref, combined->type, 0); -} - static bool combine_clip_cull(nir_shader *nir, struct exec_list *vars, @@ -134,7 +63,6 @@ combine_clip_cull(nir_shader *nir, { nir_variable *cull = NULL; nir_variable *clip = NULL; - bool progress = false; nir_foreach_variable(var, vars) { if (var->data.location == VARYING_SLOT_CLIP_DIST0) @@ -144,6 +72,9 @@ combine_clip_cull(nir_shader *nir, cull = var; } + if (!cull && !clip) + return false; + if (!cull && clip) { /* The GLSL IR lowering pass must have converted these to vectors */ if (!clip->data.compact) @@ -165,53 +96,28 @@ combine_clip_cull(nir_shader *nir, } if (clip) { - clip->data.compact = true; + assert(clip->data.compact); clip->data.how_declared = nir_var_hidden; } if (cull) { - cull->data.compact = true; + assert(clip->data.compact); cull->data.how_declared = nir_var_hidden; + cull->data.location = VARYING_SLOT_CLIP_DIST0 + clip_array_size / 4; + cull->data.location_frac = clip_array_size % 4; } - if (cull_array_size > 0) { - if (clip_array_size == 0) { - /* No clip distances, just change the cull distance location */ - cull->data.location = VARYING_SLOT_CLIP_DIST0; - } else { - /* Turn the ClipDistance array into a combined one */ - update_type(clip, nir->info.stage, clip_array_size + cull_array_size); - - /* Rewrite CullDistance to reference the combined array */ - nir_foreach_function(function, nir) { - if (function->impl) { - nir_builder b; - nir_builder_init(&b, function->impl); - - nir_foreach_block(block, function->impl) { - nir_foreach_instr(instr, block) { - rewrite_references(&b, instr, clip, clip_array_size); - } - } - } - } - - /* Delete the old CullDistance variable */ - exec_node_remove(&cull->node); - ralloc_free(cull); + nir_foreach_function(function, nir) { + if (function->impl) { + nir_metadata_preserve(function->impl, + nir_metadata_block_index | + nir_metadata_dominance | + nir_metadata_live_ssa_defs | + nir_metadata_loop_analysis); } - - nir_foreach_function(function, nir) { - if (function->impl) { - nir_metadata_preserve(function->impl, - nir_metadata_block_index | - nir_metadata_dominance); - } - } - progress = true; } - return progress; + return true; } bool -- 2.30.2