--- /dev/null
+/*
+ * Copyright © 2016 Red Hat
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "nir.h"
+#include "nir_builder.h"
+
+/* Lower complex (struct/array/mat) input and output vars to primitive types
+ * (vec4) for linking. All indirect input/output access should already be
+ * lowered (ie. nir_lower_io_to_temporaries).
+ */
+
+struct lower_io_types_state {
+ nir_shader *shader;
+ struct exec_list new_ins;
+ struct exec_list new_outs;
+};
+
+static nir_variable *
+get_new_var(struct lower_io_types_state *state, nir_variable *var,
+ const struct glsl_type *deref_type, unsigned off)
+{
+ struct exec_list *list;
+
+ if (var->data.mode == nir_var_shader_in) {
+ list = &state->new_ins;
+ } else {
+ assert(var->data.mode == nir_var_shader_out);
+ list = &state->new_outs;
+ }
+
+ nir_foreach_variable(nvar, list) {
+ if (nvar->data.location == (var->data.location + off))
+ return nvar;
+ }
+
+ /* doesn't already exist, so we need to create a new one: */
+ /* TODO figure out if scalar vs vec, and if float/int/uint/(double?)
+ * do we need to fixup interpolation mode for int vs float components
+ * of a struct, etc..
+ */
+ const struct glsl_type *ntype =
+ glsl_vector_type(glsl_get_base_type(deref_type),
+ glsl_get_vector_elements(deref_type));
+ nir_variable *nvar = nir_variable_create(state->shader, var->data.mode,
+ ntype, NULL);
+
+ nvar->name = ralloc_asprintf(nvar, "%s@%u", var->name, off);
+ nvar->data = var->data;
+ nvar->data.location += off;
+
+ /* nir_variable_create is too clever for it's own good: */
+ exec_node_remove(&nvar->node);
+ exec_node_self_link(&nvar->node); /* no delinit() :-( */
+
+ exec_list_push_tail(list, &nvar->node);
+
+ /* remove existing var from input/output list: */
+ exec_node_remove(&var->node);
+ exec_node_self_link(&var->node);
+
+ return nvar;
+}
+
+static unsigned
+get_deref_offset(struct lower_io_types_state *state, nir_deref *tail, bool vs_in)
+{
+ unsigned offset = 0;
+
+ while (tail->child != NULL) {
+ const struct glsl_type *parent_type = tail->type;
+ tail = tail->child;
+
+ if (tail->deref_type == nir_deref_type_array) {
+ nir_deref_array *deref_array = nir_deref_as_array(tail);
+
+ /* indirect inputs/outputs should already be lowered! */
+ assert(deref_array->deref_array_type == nir_deref_array_type_direct);
+
+ unsigned size = glsl_count_attribute_slots(tail->type, vs_in);
+
+ offset += size * deref_array->base_offset;
+ } else if (tail->deref_type == nir_deref_type_struct) {
+ nir_deref_struct *deref_struct = nir_deref_as_struct(tail);
+
+ for (unsigned i = 0; i < deref_struct->index; i++) {
+ const struct glsl_type *ft = glsl_get_struct_field(parent_type, i);
+ offset += glsl_count_attribute_slots(ft, vs_in);
+ }
+ }
+ }
+
+ return offset;
+}
+
+static bool
+lower_io_types_block(struct lower_io_types_state *state, nir_block *block)
+{
+ nir_foreach_instr(instr, block) {
+ if (instr->type != nir_instr_type_intrinsic)
+ continue;
+
+ nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
+
+ if ((intr->intrinsic != nir_intrinsic_load_var) &&
+ (intr->intrinsic != nir_intrinsic_store_var))
+ continue;
+
+ nir_variable *var = intr->variables[0]->var;
+
+ if ((var->data.mode != nir_var_shader_in) &&
+ (var->data.mode != nir_var_shader_out))
+ continue;
+
+ bool vs_in = (state->shader->stage == MESA_SHADER_VERTEX) &&
+ (var->data.mode == nir_var_shader_in);
+ if (glsl_count_attribute_slots(var->type, vs_in) == 1)
+ continue;
+
+ unsigned off = get_deref_offset(state, &intr->variables[0]->deref, vs_in);
+ const struct glsl_type *deref_type =
+ nir_deref_tail(&intr->variables[0]->deref)->type;
+ nir_variable *nvar = get_new_var(state, var, deref_type, off);
+
+ /* and then re-write the load/store_var deref: */
+ intr->variables[0] = nir_deref_var_create(intr, nvar);
+ }
+
+ return true;
+}
+
+static void
+lower_io_types_impl(nir_function_impl *impl, struct lower_io_types_state *state)
+{
+ nir_foreach_block(block, impl) {
+ lower_io_types_block(state, block);
+ }
+
+ nir_metadata_preserve(impl, nir_metadata_block_index |
+ nir_metadata_dominance);
+}
+
+
+void
+nir_lower_io_types(nir_shader *shader)
+{
+ struct lower_io_types_state state;
+
+ state.shader = shader;
+ exec_list_make_empty(&state.new_ins);
+ exec_list_make_empty(&state.new_outs);
+
+ nir_foreach_function(function, shader) {
+ if (function->impl)
+ lower_io_types_impl(function->impl, &state);
+ }
+
+ /* move new in/out vars to shader's lists: */
+ exec_list_append(&shader->inputs, &state.new_ins);
+ exec_list_append(&shader->outputs, &state.new_outs);
+}