/**
* @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.
*/
/**
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);
-
- if (nir_is_per_vertex_io(var, stage))
- type = glsl_array_type(type, glsl_get_length(var->type));
-
- var->type = type;
-}
-
-/**
- * Rewrite any clip/cull distances to refer to the new combined array.
- */
-static void
-rewrite_references(nir_instr *instr,
- nir_variable *combined,
- unsigned cull_offset)
-{
- if (instr->type != nir_instr_type_intrinsic)
- return;
-
- nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
-
- /* copy_var needs to be lowered to load/store before calling this pass */
- assert(intrin->intrinsic != nir_intrinsic_copy_var);
-
- if (intrin->intrinsic != nir_intrinsic_load_var &&
- intrin->intrinsic != nir_intrinsic_store_var)
- return;
-
- nir_deref_var *var_ref = intrin->variables[0];
- if (var_ref->var->data.mode != combined->data.mode)
- return;
-
- if (var_ref->var->data.location != VARYING_SLOT_CLIP_DIST0 &&
- var_ref->var->data.location != VARYING_SLOT_CULL_DIST0)
- return;
-
- /* Update types along the deref chain */
- const struct glsl_type *type = combined->type;
- nir_deref *deref = &var_ref->deref;
- while (deref) {
- deref->type = type;
- deref = deref->child;
- type = glsl_get_array_element(type);
- }
-
- /* For cull distances, add an offset to the array index */
- if (var_ref->var->data.location == VARYING_SLOT_CULL_DIST0) {
- nir_deref *tail = nir_deref_tail(&intrin->variables[0]->deref);
- nir_deref_array *array_ref = nir_deref_as_array(tail);
-
- array_ref->base_offset += cull_offset;
- }
-
- /* Point the deref at the combined array */
- var_ref->var = combined;
-
- /* There's no need to update writemasks; it's a scalar array. */
-}
-
static bool
combine_clip_cull(nir_shader *nir,
struct exec_list *vars,
{
nir_variable *cull = NULL;
nir_variable *clip = NULL;
- bool progress = false;
nir_foreach_variable(var, vars) {
if (var->data.location == VARYING_SLOT_CLIP_DIST0)
cull = var;
}
+ if (!cull && !clip) {
+ /* If this is run after optimizations and the variables have been
+ * eliminated, we should update the shader info, because no other
+ * place does that.
+ */
+ if (store_info) {
+ nir->info.clip_distance_array_size = 0;
+ nir->info.cull_distance_array_size = 0;
+ }
+ return false;
+ }
+
+ if (!cull && clip) {
+ /* The GLSL IR lowering pass must have converted these to vectors */
+ if (!clip->data.compact)
+ return false;
+
+ /* If this pass has already run, don't repeat. We would think that
+ * the combined clip/cull distance array was clip-only and mess up.
+ */
+ if (clip->data.how_declared == nir_var_hidden)
+ return false;
+ }
+
const unsigned clip_array_size = get_unwrapped_array_length(nir, clip);
const unsigned cull_array_size = get_unwrapped_array_length(nir, cull);
nir->info.cull_distance_array_size = cull_array_size;
}
- if (clip)
- clip->data.compact = true;
-
- if (cull)
- cull->data.compact = true;
-
- 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_foreach_block(block, function->impl) {
- nir_foreach_instr(instr, block) {
- rewrite_references(instr, clip, clip_array_size);
- }
- }
- }
- }
-
- /* Delete the old CullDistance variable */
- exec_node_remove(&cull->node);
- ralloc_free(cull);
- }
+ if (clip) {
+ assert(clip->data.compact);
+ clip->data.how_declared = nir_var_hidden;
+ }
- nir_foreach_function(function, nir) {
- if (function->impl) {
- nir_metadata_preserve(function->impl,
- nir_metadata_block_index |
- nir_metadata_dominance);
- }
- }
- progress = true;
+ if (cull) {
+ assert(cull->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;
}
- return progress;
+ return true;
}
bool
{
bool progress = false;
- nir_assert_lowered_derefs(nir, nir_lower_load_store_derefs);
-
if (nir->info.stage <= MESA_SHADER_GEOMETRY)
progress |= combine_clip_cull(nir, &nir->outputs, true);
if (nir->info.stage > MESA_SHADER_VERTEX)
progress |= combine_clip_cull(nir, &nir->inputs, false);
+ nir_foreach_function(function, nir) {
+ if (!function->impl)
+ continue;
+
+ if (progress) {
+ nir_metadata_preserve(function->impl,
+ nir_metadata_block_index |
+ nir_metadata_dominance |
+ nir_metadata_live_ssa_defs |
+ nir_metadata_loop_analysis);
+ } else {
+ nir_metadata_preserve(function->impl, nir_metadata_all);
+ }
+ }
+
return progress;
}
projects / mesa.git / blobdiff