--- /dev/null
+/*
+ * 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_constant_variable.cpp
+ *
+ * Marks variables assigned a single constant value over the course
+ * of the program as constant.
+ *
+ * The goal here is to trigger further constant folding and then dead
+ * code elimination. This is common with vector/matrix constructors
+ * and calls to builtin functions.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "ir.h"
+#include "ir_print_visitor.h"
+#include "ir_visitor.h"
+#include "ir_optimization.h"
+#include "glsl_types.h"
+#include "linux_list.h"
+
+struct assignment_entry {
+ struct list link;
+ int assignment_count;
+ ir_variable *var;
+ ir_constant *constval;
+};
+
+class ir_constant_variable_visitor : public ir_hierarchical_visitor {
+public:
+ ir_constant_variable_visitor()
+ {
+ list_init(&list);
+ }
+
+ virtual ir_visitor_status visit_enter(ir_assignment *);
+
+ struct list list;
+};
+
+static struct assignment_entry *
+get_assignment_entry(ir_variable *var, struct list *list)
+{
+ struct assignment_entry *entry;
+
+ list_foreach_entry(entry, struct assignment_entry, list, link) {
+ if (entry->var == var)
+ return entry;
+ }
+
+ entry = (struct assignment_entry *)calloc(1, sizeof(*entry));
+ entry->var = var;
+ list_add(&entry->link, list);
+ return entry;
+}
+
+ir_visitor_status
+ir_constant_variable_visitor::visit_enter(ir_assignment *ir)
+{
+ ir_constant *constval;
+ struct assignment_entry *entry;
+
+ entry = get_assignment_entry(ir->lhs->variable_referenced(), &this->list);
+ assert(entry);
+ entry->assignment_count++;
+
+ /* If it's already constant, don't do the work. */
+ if (entry->var->constant_value)
+ return visit_continue;
+
+ /* OK, now find if we actually have all the right conditions for
+ * this to be a constant value assigned to the var.
+ */
+ if (ir->condition) {
+ constval = ir->condition->constant_expression_value();
+ if (!constval || !constval->value.b[0])
+ return visit_continue;
+ }
+
+ ir_variable *var = ir->lhs->whole_variable_referenced();
+ if (!var)
+ return visit_continue;
+
+ constval = ir->rhs->constant_expression_value();
+ if (!constval)
+ return visit_continue;
+
+ /* Mark this entry as having a constant assignment (if the
+ * assignment count doesn't go >1). do_constant_variable will fix
+ * up the variable with the constant value later.
+ */
+ entry->constval = constval;
+
+ return visit_continue;
+}
+
+/**
+ * Does a copy propagation pass on the code present in the instruction stream.
+ */
+bool
+do_constant_variable(exec_list *instructions)
+{
+ bool progress = false;
+ ir_constant_variable_visitor v;
+
+ v.run(instructions);
+
+ while (!list_is_empty(&v.list)) {
+
+ struct assignment_entry *entry;
+ entry = list_entry(v.list.next, struct assignment_entry, link);
+
+ if (entry->assignment_count == 1 && entry->constval) {
+ entry->var->constant_value = entry->constval;
+ progress = true;
+ }
+ list_del(&entry->link);
+ free(entry);
+ }
+
+ return progress;
+}
+
+bool
+do_constant_variable_unlinked(exec_list *instructions)
+{
+ bool progress = false;
+
+ foreach_iter(exec_list_iterator, iter, *instructions) {
+ ir_instruction *ir = (ir_instruction *)iter.get();
+ ir_function *f = ir->as_function();
+ if (f) {
+ foreach_iter(exec_list_iterator, sigiter, *f) {
+ ir_function_signature *sig =
+ (ir_function_signature *) sigiter.get();
+ if (do_constant_variable(&sig->body))
+ progress = true;
+ }
+ }
+ }
+
+ return progress;
+}
--- /dev/null
+/*
+ * Copyright © 2009 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:
+ * Chris Wilson <chris@chris-wilson.co.uk>
+ *
+ */
+
+/* classic doubly-link circular list */
+struct list {
+ struct list *next, *prev;
+};
+
+static void
+list_init(struct list *list)
+{
+ list->next = list->prev = list;
+}
+
+static inline void
+__list_add(struct list *entry,
+ struct list *prev,
+ struct list *next)
+{
+ next->prev = entry;
+ entry->next = next;
+ entry->prev = prev;
+ prev->next = entry;
+}
+
+static inline void
+list_add(struct list *entry, struct list *head)
+{
+ __list_add(entry, head, head->next);
+}
+
+static inline void
+__list_del(struct list *prev, struct list *next)
+{
+ next->prev = prev;
+ prev->next = next;
+}
+
+static inline void
+list_del(struct list *entry)
+{
+ __list_del(entry->prev, entry->next);
+ list_init(entry);
+}
+
+static inline bool
+list_is_empty(struct list *head)
+{
+ return head->next == head;
+}
+
+#ifndef container_of
+#define container_of(ptr, type, member) \
+ (type *)((char *)(ptr) - (char *) &((type *)0)->member)
+#endif
+
+#define list_entry(ptr, type, member) \
+ container_of(ptr, type, member)
+
+#define list_first_entry(ptr, type, member) \
+ list_entry((ptr)->next, type, member)
+
+#define list_foreach(pos, head) \
+ for (pos = (head)->next; pos != (head); pos = pos->next)
+
+#define list_foreach_entry(pos, type, head, member) \
+ for (pos = list_entry((head)->next, type, member);\
+ &pos->member != (head); \
+ pos = list_entry(pos->member.next, type, member))
projects / mesa.git / commitdiff