diff --git a/src/intel/vulkan/anv_nir_lower_multiview.c b/src/intel/vulkan/anv_nir_lower_multiview.c index 75bc01868ba..0502b1e3df7 100644 --- a/src/intel/vulkan/anv_nir_lower_multiview.c +++ b/src/intel/vulkan/anv_nir_lower_multiview.c @@ -150,166 +150,6 @@ build_view_index(struct lower_multiview_state *state) return state->view_index; } -/* Primitive Replication allows a shader to write different positions for each - * view in the same execution. If only the position depends on the view, then - * it is possible to use the feature instead of instancing to implement - * multiview. - */ -static bool -lower_multiview_with_primitive_replication(nir_shader *shader, - struct anv_graphics_pipeline *pipeline) -{ - if (shader->info.stage == MESA_SHADER_FRAGMENT) - return false; - - assert(shader->info.stage == MESA_SHADER_VERTEX); - - uint32_t view_mask = pipeline->subpass->view_mask; - int view_count = util_bitcount(view_mask); - assert(view_count > 1 && view_count <= MAX_VIEWS_FOR_PRIMITIVE_REPLICATION); - - nir_function_impl *entrypoint = nir_shader_get_entrypoint(shader); - - /* Update position to refer to an array. */ - nir_variable *pos_var = NULL; - nir_foreach_shader_out_variable(var, shader) { - if (var->data.location == VARYING_SLOT_POS) { - assert(var->type == glsl_vec4_type()); - var->type = glsl_array_type(glsl_vec4_type(), view_count, 0); - var->data.per_view = true; - pos_var = var; - break; - } - } - - assert(pos_var); - - nir_cf_list body; - nir_cf_list_extract(&body, &entrypoint->body); - - nir_builder b; - nir_builder_init(&b, entrypoint); - b.cursor = nir_after_cf_list(&entrypoint->body); - - /* Fill Layer ID with zero. Replication will use that as base to apply the - * RTAI offsets. - */ - nir_variable *layer_id_out = - nir_variable_create(shader, nir_var_shader_out, - glsl_int_type(), "layer ID"); - layer_id_out->data.location = VARYING_SLOT_LAYER; - nir_store_var(&b, layer_id_out, nir_imm_zero(&b, 1, 32), 0x1); - - /* Loop Index will go from 0 to view_count. */ - nir_variable *loop_index_var = - nir_local_variable_create(entrypoint, glsl_uint_type(), "loop_index"); - nir_deref_instr *loop_index_deref = nir_build_deref_var(&b, loop_index_var); - nir_store_deref(&b, loop_index_deref, nir_imm_int(&b, 0), 1); - - /* Array of view index values that are active in the loop. Note that the - * loop index only matches the view index if there are no gaps in the - * view_mask. - */ - nir_variable *view_index_var = nir_local_variable_create( - entrypoint, glsl_array_type(glsl_uint_type(), view_count, 0), "view_index"); - nir_deref_instr *view_index_deref = nir_build_deref_var(&b, view_index_var); - { - int array_position = 0; - uint32_t view_index; - for_each_bit(view_index, view_mask) { - nir_store_deref(&b, nir_build_deref_array_imm(&b, view_index_deref, array_position), - nir_imm_int(&b, view_index), 1); - array_position++; - } - } - - /* Create the equivalent of - * - * while (true): - * if (loop_index >= view_count): - * break - * - * view_index = active_indices[loop_index] - * pos_deref = &pos[loop_index] - * - * # Placeholder for the body to be reinserted. - * - * loop_index += 1 - * - * Later both `view_index` and `pos_deref` will be used to rewrite the - * original shader body. - */ - - nir_loop* loop = nir_push_loop(&b); - - nir_ssa_def *loop_index = nir_load_deref(&b, loop_index_deref); - nir_ssa_def *cmp = nir_ige(&b, loop_index, nir_imm_int(&b, view_count)); - nir_if *loop_check = nir_push_if(&b, cmp); - nir_jump(&b, nir_jump_break); - nir_pop_if(&b, loop_check); - - nir_ssa_def *view_index = - nir_load_deref(&b, nir_build_deref_array(&b, view_index_deref, loop_index)); - nir_deref_instr *pos_deref = - nir_build_deref_array(&b, nir_build_deref_var(&b, pos_var), loop_index); - - nir_store_deref(&b, loop_index_deref, nir_iadd_imm(&b, loop_index, 1), 1); - nir_pop_loop(&b, loop); - - /* Reinsert the body. */ - b.cursor = nir_after_instr(&pos_deref->instr); - nir_cf_reinsert(&body, b.cursor); - - nir_foreach_block(block, entrypoint) { - nir_foreach_instr_safe(instr, block) { - if (instr->type != nir_instr_type_intrinsic) - continue; - - nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); - - switch (intrin->intrinsic) { - case nir_intrinsic_load_view_index: { - assert(intrin->dest.is_ssa); - nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(view_index)); - break; - } - - case nir_intrinsic_store_deref: { - nir_variable *var = nir_intrinsic_get_var(intrin, 0); - if (var == pos_var) { - nir_deref_instr *old_deref = nir_src_as_deref(intrin->src[0]); - - nir_instr_rewrite_src(instr, &intrin->src[0], - nir_src_for_ssa(&pos_deref->dest.ssa)); - - /* Remove old deref since it has the wrong type. */ - nir_deref_instr_remove_if_unused(old_deref); - } - break; - } - - case nir_intrinsic_load_deref: - if (nir_intrinsic_get_var(intrin, 0) == pos_var) { - unreachable("Should have lowered I/O to temporaries " - "so no load_deref on position output is expected."); - } - break; - - case nir_intrinsic_copy_deref: - unreachable("Should have lowered copy_derefs at this point"); - break; - - default: - /* Do nothing. */ - break; - } - } - } - - nir_metadata_preserve(entrypoint, nir_metadata_none); - return true; -} - bool anv_nir_lower_multiview(nir_shader *shader, struct anv_graphics_pipeline *pipeline) @@ -321,16 +161,42 @@ anv_nir_lower_multiview(nir_shader *shader, if (view_mask == 0) return false; - if (pipeline->use_primitive_replication) - return lower_multiview_with_primitive_replication(shader, pipeline); + /* This pass assumes a single entrypoint */ + nir_function_impl *entrypoint = nir_shader_get_entrypoint(shader); + + /* Primitive Replication allows a shader to write different positions for + * each view in the same execution. If only the position depends on the + * view, then it is possible to use the feature instead of instancing to + * implement multiview. + */ + if (pipeline->use_primitive_replication) { + if (shader->info.stage == MESA_SHADER_FRAGMENT) + return false; + + bool progress = nir_lower_multiview(shader, pipeline->subpass->view_mask); + + if (progress) { + nir_builder b; + nir_builder_init(&b, entrypoint); + b.cursor = nir_before_cf_list(&entrypoint->body); + + /* Fill Layer ID with zero. Replication will use that as base to + * apply the RTAI offsets. + */ + nir_variable *layer_id_out = + nir_variable_create(shader, nir_var_shader_out, + glsl_int_type(), "layer ID"); + layer_id_out->data.location = VARYING_SLOT_LAYER; + nir_store_var(&b, layer_id_out, nir_imm_zero(&b, 1, 32), 0x1); + } + + return progress; + } struct lower_multiview_state state = { .view_mask = view_mask, }; - /* This pass assumes a single entrypoint */ - nir_function_impl *entrypoint = nir_shader_get_entrypoint(shader); - nir_builder_init(&state.builder, entrypoint); bool progress = false; @@ -401,141 +267,6 @@ anv_nir_lower_multiview(nir_shader *shader, return progress; } -static bool -shader_writes_to_memory(nir_shader *shader) -{ - /* With multiview, we would need to ensure that memory writes happen either - * once or once per view. Since combination of multiview and memory writes - * is not expected, we'll just skip this optimization in this case. - */ - - nir_function_impl *entrypoint = nir_shader_get_entrypoint(shader); - - nir_foreach_block(block, entrypoint) { - nir_foreach_instr(instr, block) { - if (instr->type != nir_instr_type_intrinsic) - continue; - nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); - - switch (intrin->intrinsic) { - case nir_intrinsic_deref_atomic_add: - case nir_intrinsic_deref_atomic_imin: - case nir_intrinsic_deref_atomic_umin: - case nir_intrinsic_deref_atomic_imax: - case nir_intrinsic_deref_atomic_umax: - case nir_intrinsic_deref_atomic_and: - case nir_intrinsic_deref_atomic_or: - case nir_intrinsic_deref_atomic_xor: - case nir_intrinsic_deref_atomic_exchange: - case nir_intrinsic_deref_atomic_comp_swap: - case nir_intrinsic_store_ssbo: - case nir_intrinsic_ssbo_atomic_add: - case nir_intrinsic_ssbo_atomic_imin: - case nir_intrinsic_ssbo_atomic_umin: - case nir_intrinsic_ssbo_atomic_imax: - case nir_intrinsic_ssbo_atomic_umax: - case nir_intrinsic_ssbo_atomic_and: - case nir_intrinsic_ssbo_atomic_or: - case nir_intrinsic_ssbo_atomic_xor: - case nir_intrinsic_ssbo_atomic_exchange: - case nir_intrinsic_ssbo_atomic_comp_swap: - case nir_intrinsic_store_shared: - case nir_intrinsic_shared_atomic_add: - case nir_intrinsic_shared_atomic_imin: - case nir_intrinsic_shared_atomic_umin: - case nir_intrinsic_shared_atomic_imax: - case nir_intrinsic_shared_atomic_umax: - case nir_intrinsic_shared_atomic_and: - case nir_intrinsic_shared_atomic_or: - case nir_intrinsic_shared_atomic_xor: - case nir_intrinsic_shared_atomic_exchange: - case nir_intrinsic_shared_atomic_comp_swap: - case nir_intrinsic_image_deref_store: - case nir_intrinsic_image_deref_atomic_add: - case nir_intrinsic_image_deref_atomic_umin: - case nir_intrinsic_image_deref_atomic_umax: - case nir_intrinsic_image_deref_atomic_imin: - case nir_intrinsic_image_deref_atomic_imax: - case nir_intrinsic_image_deref_atomic_and: - case nir_intrinsic_image_deref_atomic_or: - case nir_intrinsic_image_deref_atomic_xor: - case nir_intrinsic_image_deref_atomic_exchange: - case nir_intrinsic_image_deref_atomic_comp_swap: - return true; - - default: - /* Keep walking. */ - break; - } - } - } - - return false; -} - -static bool -shader_uses_view_index(nir_shader *shader) -{ - nir_function_impl *entrypoint = nir_shader_get_entrypoint(shader); - - nir_foreach_block(block, entrypoint) { - nir_foreach_instr(instr, block) { - if (instr->type != nir_instr_type_intrinsic) - continue; - - nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); - if (intrin->intrinsic == nir_intrinsic_load_view_index) - return true; - } - } - - return false; -} - -static bool -shader_only_position_uses_view_index(nir_shader *shader) -{ - nir_shader *shader_no_position = nir_shader_clone(NULL, shader); - nir_function_impl *entrypoint = nir_shader_get_entrypoint(shader_no_position); - - /* Remove the store position from a cloned shader. */ - nir_foreach_block(block, entrypoint) { - nir_foreach_instr_safe(instr, block) { - if (instr->type != nir_instr_type_intrinsic) - continue; - - nir_intrinsic_instr *store = nir_instr_as_intrinsic(instr); - if (store->intrinsic != nir_intrinsic_store_deref) - continue; - - nir_variable *var = nir_intrinsic_get_var(store, 0); - if (var->data.location != VARYING_SLOT_POS) - continue; - - nir_instr_remove(&store->instr); - } - } - - /* Clean up shader so unused load_view_index intrinsics are removed. */ - bool progress; - do { - progress = false; - progress |= nir_opt_dead_cf(shader_no_position); - - /* Peephole select will drop if-blocks that have then and else empty, - * which will remove the usage of an SSA in the condition. - */ - progress |= nir_opt_peephole_select(shader_no_position, 0, false, false); - - progress |= nir_opt_dce(shader_no_position); - } while (progress); - - bool uses_view_index = shader_uses_view_index(shader_no_position); - - ralloc_free(shader_no_position); - return !uses_view_index; -} - bool anv_check_for_primitive_replication(nir_shader **shaders, struct anv_graphics_pipeline *pipeline) @@ -570,19 +301,9 @@ anv_check_for_primitive_replication(nir_shader **shaders, if (view_count == 1 || view_count > primitive_replication_max_views) return false; - bool vs_writes_position = false; - nir_foreach_shader_out_variable(var, shaders[MESA_SHADER_VERTEX]) { - if (var->data.location == VARYING_SLOT_POS) { - vs_writes_position = true; - break; - } - } - - /* Don't bother handling this edge case with Primitive Replication. */ - if (!vs_writes_position) + /* We can't access the view index in the fragment shader. */ + if (nir_shader_uses_view_index(shaders[MESA_SHADER_FRAGMENT])) return false; - return !shader_uses_view_index(shaders[MESA_SHADER_FRAGMENT]) && - !shader_writes_to_memory(shaders[MESA_SHADER_VERTEX]) && - shader_only_position_uses_view_index(shaders[MESA_SHADER_VERTEX]); + return nir_can_lower_multiview(shaders[MESA_SHADER_VERTEX]); }