/* A hash table mapping derefs to registers */
struct hash_table *regs_table;
- /* A growing array of derefs that we have encountered. There is exactly
- * one element of this array per element in the hash table. This is
- * used to make adding register initialization code deterministic.
- */
- nir_array derefs_array;
-
bool progress;
};
{
uint32_t hash = hash_deref(deref);
+ assert(deref->var->constant_initializer == NULL);
+
struct hash_entry *entry =
_mesa_hash_table_search_pre_hashed(state->regs_table, hash, deref);
if (entry)
reg->bit_size = glsl_get_bit_size(tail->type);
_mesa_hash_table_insert_pre_hashed(state->regs_table, hash, deref, reg);
- nir_array_add(&state->derefs_array, nir_deref_var *, deref);
return reg;
}
return true;
}
-static nir_block *
-compute_reg_usedef_lca(nir_register *reg)
-{
- nir_block *lca = NULL;
-
- list_for_each_entry(nir_dest, def_dest, ®->defs, reg.def_link)
- lca = nir_dominance_lca(lca, def_dest->reg.parent_instr->block);
-
- list_for_each_entry(nir_src, use_src, ®->uses, use_link)
- lca = nir_dominance_lca(lca, use_src->parent_instr->block);
-
- list_for_each_entry(nir_src, use_src, ®->if_uses, use_link) {
- nir_cf_node *prev_node = nir_cf_node_prev(&use_src->parent_if->cf_node);
- lca = nir_dominance_lca(lca, nir_cf_node_as_block(prev_node));
- }
-
- return lca;
-}
-
-static void
-insert_constant_initializer(nir_deref_var *deref_head, nir_deref *deref_tail,
- nir_block *block,
- struct locals_to_regs_state *state)
-{
- if (deref_tail->child) {
- switch (deref_tail->child->deref_type) {
- case nir_deref_type_array: {
- unsigned array_elems = glsl_get_length(deref_tail->type);
-
- nir_deref_array arr_deref;
- arr_deref.deref = *deref_tail->child;
- arr_deref.deref_array_type = nir_deref_array_type_direct;
-
- nir_deref *old_child = deref_tail->child;
- deref_tail->child = &arr_deref.deref;
- for (unsigned i = 0; i < array_elems; i++) {
- arr_deref.base_offset = i;
- insert_constant_initializer(deref_head, &arr_deref.deref,
- block, state);
- }
- deref_tail->child = old_child;
- return;
- }
-
- case nir_deref_type_struct:
- insert_constant_initializer(deref_head, deref_tail->child,
- block, state);
- return;
-
- default:
- unreachable("Invalid deref child type");
- }
- }
-
- assert(deref_tail->child == NULL);
-
- nir_load_const_instr *load =
- nir_deref_get_const_initializer_load(state->shader, deref_head);
- nir_instr_insert_before_block(block, &load->instr);
-
- nir_src reg_src = get_deref_reg_src(deref_head, &load->instr, state);
-
- nir_alu_instr *mov = nir_alu_instr_create(state->shader, nir_op_imov);
- mov->src[0].src = nir_src_for_ssa(&load->def);
- mov->dest.write_mask = (1 << load->def.num_components) - 1;
- mov->dest.dest.is_ssa = false;
- mov->dest.dest.reg.reg = reg_src.reg.reg;
- mov->dest.dest.reg.base_offset = reg_src.reg.base_offset;
- mov->dest.dest.reg.indirect = reg_src.reg.indirect;
-
- nir_instr_insert_after(&load->instr, &mov->instr);
- state->progress = true;
-}
-
static bool
nir_lower_locals_to_regs_impl(nir_function_impl *impl)
{
state.impl = impl;
state.progress = false;
state.regs_table = _mesa_hash_table_create(NULL, hash_deref, derefs_equal);
- nir_array_init(&state.derefs_array, NULL);
nir_metadata_require(impl, nir_metadata_dominance);
lower_locals_to_regs_block(block, &state);
}
- nir_array_foreach(&state.derefs_array, nir_deref_var *, deref_ptr) {
- nir_deref_var *deref = *deref_ptr;
- struct hash_entry *deref_entry =
- _mesa_hash_table_search(state.regs_table, deref);
- assert(deref_entry && deref_entry->key == deref);
- nir_register *reg = (nir_register *)deref_entry->data;
-
- if (deref->var->constant_initializer == NULL)
- continue;
-
- nir_block *usedef_lca = compute_reg_usedef_lca(reg);
-
- insert_constant_initializer(deref, &deref->deref, usedef_lca, &state);
- }
-
nir_metadata_preserve(impl, nir_metadata_block_index |
nir_metadata_dominance);
- nir_array_fini(&state.derefs_array);
_mesa_hash_table_destroy(state.regs_table, NULL);
return state.progress;