| /* |
| * Copyright © 2010 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. |
| */ |
| |
| /** |
| * \file opt_dead_functions.cpp |
| * |
| * Eliminates unused functions from the linked program. |
| */ |
| |
| #include "ir.h" |
| #include "ir_visitor.h" |
| #include "ir_expression_flattening.h" |
| #include "glsl_types.h" |
| |
| namespace { |
| |
| class signature_entry : public exec_node |
| { |
| public: |
| signature_entry(ir_function_signature *sig) |
| { |
| this->signature = sig; |
| this->used = false; |
| } |
| |
| ir_function_signature *signature; |
| bool used; |
| }; |
| |
| class ir_dead_functions_visitor : public ir_hierarchical_visitor { |
| public: |
| ir_dead_functions_visitor() |
| { |
| this->mem_ctx = ralloc_context(NULL); |
| } |
| |
| ~ir_dead_functions_visitor() |
| { |
| ralloc_free(this->mem_ctx); |
| } |
| |
| virtual ir_visitor_status visit_enter(ir_function_signature *); |
| virtual ir_visitor_status visit_enter(ir_call *); |
| |
| signature_entry *get_signature_entry(ir_function_signature *var); |
| |
| /* List of signature_entry */ |
| exec_list signature_list; |
| void *mem_ctx; |
| }; |
| |
| } /* unnamed namespace */ |
| |
| signature_entry * |
| ir_dead_functions_visitor::get_signature_entry(ir_function_signature *sig) |
| { |
| foreach_in_list(signature_entry, entry, &this->signature_list) { |
| if (entry->signature == sig) |
| return entry; |
| } |
| |
| signature_entry *entry = new(mem_ctx) signature_entry(sig); |
| this->signature_list.push_tail(entry); |
| return entry; |
| } |
| |
| |
| ir_visitor_status |
| ir_dead_functions_visitor::visit_enter(ir_function_signature *ir) |
| { |
| signature_entry *entry = this->get_signature_entry(ir); |
| |
| if (strcmp(ir->function_name(), "main") == 0) { |
| entry->used = true; |
| } |
| |
| |
| |
| return visit_continue; |
| } |
| |
| |
| ir_visitor_status |
| ir_dead_functions_visitor::visit_enter(ir_call *ir) |
| { |
| signature_entry *entry = this->get_signature_entry(ir->callee); |
| |
| entry->used = true; |
| |
| return visit_continue; |
| } |
| |
| bool |
| do_dead_functions(exec_list *instructions) |
| { |
| ir_dead_functions_visitor v; |
| bool progress = false; |
| |
| visit_list_elements(&v, instructions); |
| |
| /* Now that we've figured out which function signatures are used, remove |
| * the unused ones, and remove function definitions that have no more |
| * signatures. |
| */ |
| foreach_in_list_safe(signature_entry, entry, &v.signature_list) { |
| if (!entry->used) { |
| entry->signature->remove(); |
| delete entry->signature; |
| progress = true; |
| } |
| delete(entry); |
| } |
| |
| /* We don't just do this above when we nuked a signature because of |
| * const pointers. |
| */ |
| foreach_in_list_safe(ir_instruction, ir, instructions) { |
| ir_function *func = ir->as_function(); |
| |
| if (func && func->signatures.is_empty()) { |
| /* At this point (post-linking), the symbol table is no |
| * longer in use, so not removing the function from the |
| * symbol table should be OK. |
| */ |
| func->remove(); |
| delete func; |
| progress = true; |
| } |
| } |
| |
| return progress; |
| } |