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-rw-r--r--src/glsl/ir_dead_code_local.cpp229
1 files changed, 0 insertions, 229 deletions
diff --git a/src/glsl/ir_dead_code_local.cpp b/src/glsl/ir_dead_code_local.cpp
deleted file mode 100644
index 4bbedf0..0000000
--- a/src/glsl/ir_dead_code_local.cpp
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@@ -1,229 +0,0 @@
-/*
- * 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 ir_dead_code_local.cpp
- *
- * Eliminates local dead assignments from the code.
- *
- * This operates on basic blocks, tracking assignments and finding if
- * they're used before the variable is completely reassigned.
- *
- * Compare this to ir_dead_code.cpp, which operates globally looking
- * for assignments to variables that are never read.
- */
-
-#include "ir.h"
-#include "ir_basic_block.h"
-#include "ir_optimization.h"
-#include "glsl_types.h"
-
-static bool debug = false;
-
-class assignment_entry : public exec_node
-{
-public:
- assignment_entry(ir_variable *lhs, ir_instruction *ir)
- {
- assert(lhs);
- assert(ir);
- this->lhs = lhs;
- this->ir = ir;
- }
-
- ir_variable *lhs;
- ir_instruction *ir;
-};
-
-class kill_for_derefs_visitor : public ir_hierarchical_visitor {
-public:
- kill_for_derefs_visitor(exec_list *assignments)
- {
- this->assignments = assignments;
- }
-
- virtual ir_visitor_status visit(ir_dereference_variable *ir)
- {
- ir_variable *const var = ir->variable_referenced();
-
- foreach_iter(exec_list_iterator, iter, *this->assignments) {
- assignment_entry *entry = (assignment_entry *)iter.get();
-
- if (entry->lhs == var) {
- if (debug)
- printf("kill %s\n", entry->lhs->name);
- entry->remove();
- }
- }
-
- return visit_continue;
- }
-
-private:
- exec_list *assignments;
-};
-
-class array_index_visit : public ir_hierarchical_visitor {
-public:
- array_index_visit(ir_hierarchical_visitor *v)
- {
- this->visitor = v;
- }
-
- virtual ir_visitor_status visit_enter(class ir_dereference_array *ir)
- {
- ir->array_index->accept(visitor);
- return visit_continue;
- }
-
- static void run(ir_instruction *ir, ir_hierarchical_visitor *v)
- {
- array_index_visit top_visit(v);
- ir->accept(& top_visit);
- }
-
- ir_hierarchical_visitor *visitor;
-};
-
-
-/**
- * Adds an entry to the available copy list if it's a plain assignment
- * of a variable to a variable.
- */
-static bool
-process_assignment(void *ctx, ir_assignment *ir, exec_list *assignments)
-{
- ir_variable *var = NULL;
- bool progress = false;
- kill_for_derefs_visitor v(assignments);
-
- /* Kill assignment entries for things used to produce this assignment. */
- ir->rhs->accept(&v);
- if (ir->condition) {
- ir->condition->accept(&v);
- }
-
- /* Kill assignment enties used as array indices.
- */
- array_index_visit::run(ir->lhs, &v);
- var = ir->lhs->variable_referenced();
- assert(var);
-
- bool always_assign = true;
- if (ir->condition) {
- ir_constant *condition = ir->condition->as_constant();
- if (!condition || !condition->value.b[0])
- always_assign = false;
- }
-
- /* Now, check if we did a whole-variable assignment. */
- if (always_assign && (ir->whole_variable_written() != NULL)) {
- /* We did a whole-variable assignment. So, any instruction in
- * the assignment list with the same LHS is dead.
- */
- if (debug)
- printf("looking for %s to remove\n", var->name);
- foreach_iter(exec_list_iterator, iter, *assignments) {
- assignment_entry *entry = (assignment_entry *)iter.get();
-
- if (entry->lhs == var) {
- if (debug)
- printf("removing %s\n", var->name);
- entry->ir->remove();
- entry->remove();
- progress = true;
- }
- }
- }
-
- /* Add this instruction to the assignment list available to be removed.
- * But not if the assignment has other side effects.
- */
- if (ir_has_call(ir))
- return progress;
-
- assignment_entry *entry = new(ctx) assignment_entry(var, ir);
- assignments->push_tail(entry);
-
- if (debug) {
- printf("add %s\n", var->name);
-
- printf("current entries\n");
- foreach_iter(exec_list_iterator, iter, *assignments) {
- assignment_entry *entry = (assignment_entry *)iter.get();
-
- printf(" %s\n", entry->lhs->name);
- }
- }
-
- return progress;
-}
-
-static void
-dead_code_local_basic_block(ir_instruction *first,
- ir_instruction *last,
- void *data)
-{
- ir_instruction *ir, *ir_next;
- /* List of avaialble_copy */
- exec_list assignments;
- bool *out_progress = (bool *)data;
- bool progress = false;
-
- void *ctx = talloc_new(NULL);
- /* Safe looping, since process_assignment */
- for (ir = first, ir_next = (ir_instruction *)first->next;;
- ir = ir_next, ir_next = (ir_instruction *)ir->next) {
- ir_assignment *ir_assign = ir->as_assignment();
-
- if (debug) {
- ir->print();
- printf("\n");
- }
-
- if (ir_assign) {
- progress = process_assignment(ctx, ir_assign, &assignments) || progress;
- } else {
- kill_for_derefs_visitor kill(&assignments);
- ir->accept(&kill);
- }
-
- if (ir == last)
- break;
- }
- *out_progress = progress;
- talloc_free(ctx);
-}
-
-/**
- * Does a copy propagation pass on the code present in the instruction stream.
- */
-bool
-do_dead_code_local(exec_list *instructions)
-{
- bool progress = false;
-
- call_for_basic_blocks(instructions, dead_code_local_basic_block, &progress);
-
- return progress;
-}
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