From 6962c332e5e94dce48b472cb181095cc74c67816 Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Tue, 2 Dec 2014 12:48:38 -0800 Subject: [PATCH] nir: Add a pass to lower global variables to local variables Reviewed-by: Connor Abbott --- src/glsl/Makefile.sources | 1 + src/glsl/nir/nir.h | 2 + src/glsl/nir/nir_lower_global_vars_to_local.c | 106 ++++++++++++++++++ 3 files changed, 109 insertions(+) create mode 100644 src/glsl/nir/nir_lower_global_vars_to_local.c diff --git a/src/glsl/Makefile.sources b/src/glsl/Makefile.sources index 53c3e9876cd..3f5c0bd58ab 100644 --- a/src/glsl/Makefile.sources +++ b/src/glsl/Makefile.sources @@ -22,6 +22,7 @@ NIR_FILES = \ $(GLSL_SRCDIR)/nir/nir_intrinsics.h \ $(GLSL_SRCDIR)/nir/nir_live_variables.c \ $(GLSL_SRCDIR)/nir/nir_lower_atomics.c \ + $(GLSL_SRCDIR)/nir/nir_lower_global_vars_to_local.c \ $(GLSL_SRCDIR)/nir/nir_lower_locals_to_regs.c \ $(GLSL_SRCDIR)/nir/nir_lower_io.c \ $(GLSL_SRCDIR)/nir/nir_lower_samplers.cpp \ diff --git a/src/glsl/nir/nir.h b/src/glsl/nir/nir.h index 3976a3e43df..32cc302da0c 100644 --- a/src/glsl/nir/nir.h +++ b/src/glsl/nir/nir.h @@ -1358,6 +1358,8 @@ void nir_dump_cfg(nir_shader *shader, FILE *fp); void nir_split_var_copies(nir_shader *shader); +void nir_lower_global_vars_to_local(nir_shader *shader); + void nir_lower_locals_to_regs(nir_shader *shader); void nir_lower_io(nir_shader *shader); diff --git a/src/glsl/nir/nir_lower_global_vars_to_local.c b/src/glsl/nir/nir_lower_global_vars_to_local.c new file mode 100644 index 00000000000..0cd8740cc12 --- /dev/null +++ b/src/glsl/nir/nir_lower_global_vars_to_local.c @@ -0,0 +1,106 @@ +/* + * Copyright © 2014 Intel Corporation + * + * 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. + * + * Authors: + * Jason Ekstrand (jason@jlekstrand.net) + * + */ + +/* + * This lowering pass detects when a global variable is only being used by + * one function and makes it local to that function + */ + +#include "nir.h" + +struct global_to_local_state { + nir_function_impl *impl; + /* A hash table keyed on variable pointers that stores the unique + * nir_function_impl that uses the given variable. If a variable is + * used in multiple functions, the data for the given key will be NULL. + */ + struct hash_table *var_func_table; +}; + +static bool +mark_global_var_uses_block(nir_block *block, void *void_state) +{ + struct global_to_local_state *state = void_state; + + nir_foreach_instr(block, instr) { + if (instr->type != nir_instr_type_intrinsic) + continue; + + nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); + unsigned num_vars = nir_intrinsic_infos[intrin->intrinsic].num_variables; + + for (unsigned i = 0; i < num_vars; i++) { + nir_variable *var = intrin->variables[i]->var; + if (var->data.mode != nir_var_global) + continue; + + struct hash_entry *entry = + _mesa_hash_table_search(state->var_func_table, var); + + if (entry) { + if (entry->data != state->impl) + entry->data = NULL; + } else { + _mesa_hash_table_insert(state->var_func_table, var, state->impl); + } + } + } + + return true; +} + +void +nir_lower_global_vars_to_local(nir_shader *shader) +{ + struct global_to_local_state state; + + state.var_func_table = _mesa_hash_table_create(NULL, _mesa_hash_pointer, + _mesa_key_pointer_equal); + + nir_foreach_overload(shader, overload) { + if (overload->impl) { + state.impl = overload->impl; + nir_foreach_block(overload->impl, mark_global_var_uses_block, &state); + } + } + + struct hash_entry *entry; + hash_table_foreach(state.var_func_table, entry) { + nir_variable *var = (void *)entry->key; + nir_function_impl *impl = entry->data; + + assert(var->data.mode == nir_var_global); + + if (impl != NULL) { + exec_node_remove(&var->node); + var->data.mode = nir_var_local; + exec_list_push_tail(&impl->locals, &var->node); + } + } + + _mesa_hash_table_destroy(state.var_func_table, NULL); +} -- 2.30.2