/* * Copyright © 2015 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. */ #include "nir.h" /** * \file nir_sweep.c * * The nir_sweep() pass performs a mark and sweep pass over a nir_shader's associated * memory - anything still connected to the program will be kept, and any dead memory * we dropped on the floor will be freed. * * The expectation is that drivers should call this when finished compiling the shader * (after any optimization, lowering, and so on). However, it's also fine to call it * earlier, and even many times, trading CPU cycles for memory savings. */ #define steal_list(mem_ctx, type, list) \ foreach_list_typed(type, obj, node, list) { ralloc_steal(mem_ctx, obj); } static void sweep_cf_node(nir_shader *nir, nir_cf_node *cf_node); static bool sweep_src_indirect(nir_src *src, void *nir) { if (!src->is_ssa && src->reg.indirect) ralloc_steal(nir, src->reg.indirect); return true; } static bool sweep_dest_indirect(nir_dest *dest, void *nir) { if (!dest->is_ssa && dest->reg.indirect) ralloc_steal(nir, dest->reg.indirect); return true; } static void sweep_block(nir_shader *nir, nir_block *block) { ralloc_steal(nir, block); /* sweep_impl will mark all metadata invalid. We can safely release all of * this here. */ ralloc_free(block->live_in); block->live_in = NULL; ralloc_free(block->live_out); block->live_out = NULL; nir_foreach_instr(instr, block) { ralloc_steal(nir, instr); nir_foreach_src(instr, sweep_src_indirect, nir); nir_foreach_dest(instr, sweep_dest_indirect, nir); } } static void sweep_if(nir_shader *nir, nir_if *iff) { ralloc_steal(nir, iff); foreach_list_typed(nir_cf_node, cf_node, node, &iff->then_list) { sweep_cf_node(nir, cf_node); } foreach_list_typed(nir_cf_node, cf_node, node, &iff->else_list) { sweep_cf_node(nir, cf_node); } } static void sweep_loop(nir_shader *nir, nir_loop *loop) { ralloc_steal(nir, loop); foreach_list_typed(nir_cf_node, cf_node, node, &loop->body) { sweep_cf_node(nir, cf_node); } } static void sweep_cf_node(nir_shader *nir, nir_cf_node *cf_node) { switch (cf_node->type) { case nir_cf_node_block: sweep_block(nir, nir_cf_node_as_block(cf_node)); break; case nir_cf_node_if: sweep_if(nir, nir_cf_node_as_if(cf_node)); break; case nir_cf_node_loop: sweep_loop(nir, nir_cf_node_as_loop(cf_node)); break; default: unreachable("Invalid CF node type"); } } static void sweep_impl(nir_shader *nir, nir_function_impl *impl) { ralloc_steal(nir, impl); steal_list(nir, nir_variable, &impl->locals); steal_list(nir, nir_register, &impl->registers); foreach_list_typed(nir_cf_node, cf_node, node, &impl->body) { sweep_cf_node(nir, cf_node); } sweep_block(nir, impl->end_block); /* Wipe out all the metadata, if any. */ nir_metadata_preserve(impl, nir_metadata_none); } static void sweep_function(nir_shader *nir, nir_function *f) { ralloc_steal(nir, f); ralloc_steal(nir, f->params); if (f->impl) sweep_impl(nir, f->impl); } void nir_sweep(nir_shader *nir) { void *rubbish = ralloc_context(NULL); /* First, move ownership of all the memory to a temporary context; assume dead. */ ralloc_adopt(rubbish, nir); ralloc_steal(nir, (char *)nir->info.name); if (nir->info.label) ralloc_steal(nir, (char *)nir->info.label); /* Variables and registers are not dead. Steal them back. */ steal_list(nir, nir_variable, &nir->uniforms); steal_list(nir, nir_variable, &nir->inputs); steal_list(nir, nir_variable, &nir->outputs); steal_list(nir, nir_variable, &nir->shared); steal_list(nir, nir_variable, &nir->globals); steal_list(nir, nir_variable, &nir->system_values); steal_list(nir, nir_register, &nir->registers); /* Recurse into functions, stealing their contents back. */ foreach_list_typed(nir_function, func, node, &nir->functions) { sweep_function(nir, func); } ralloc_steal(nir, nir->constant_data); /* Free everything we didn't steal back. */ ralloc_free(rubbish); }