* @file
* @brief conv node optimisation
* @author Matthias Braun, Christoph Mallon
- * @version $Id: condeval.c 13543 2007-04-29 19:29:02Z beck $
+ * @version $Id$
*
* Try to minimize the number of conv nodes by changing modes of operations.
* The typical example is the following structure:
#include "config.h"
#endif
+#include "iroptimize.h"
+
#include <assert.h>
#include "debug.h"
#include "ircons.h"
#include "irgmod.h"
+#include "irgopt.h"
#include "irnode_t.h"
#include "iredges_t.h"
#include "irgwalk.h"
static
int is_optimizable_node(const ir_node *node)
{
- if(is_Const(node)) {
- ir_mode *mode = get_irn_mode(node);
- /* tarval module is incomplete and can't convert floats to ints */
- if(!mode_is_int(mode))
- return 0;
- return 1;
- }
- return is_Add(node) || is_Sub(node) || is_Mul(node);
+ return
+ is_Add(node) ||
+ is_Sub(node) ||
+ is_Mul(node) ||
+ is_Phi(node);
+}
+
+static tarval* conv_const_tv(const ir_node* cnst, ir_mode* dest_mode)
+{
+ return tarval_convert_to(get_Const_tarval(cnst), dest_mode);
}
static
int get_conv_costs(const ir_node *node, ir_mode *dest_mode)
{
ir_mode *mode = get_irn_mode(node);
+ size_t arity;
+ size_t i;
+ int costs;
- if(mode == dest_mode)
+ if (mode == dest_mode)
return 0;
- /* TODO... */
- if(!is_Const(node) && get_irn_n_edges(node) > 1) {
+ if (is_Const(node)) {
+ /* TODO tarval module is incomplete and can't convert floats to ints */
+ return conv_const_tv(node, dest_mode) == tarval_bad ? 1 : 0;
+ }
+
+ if (get_irn_n_edges(node) > 1) {
DB((dbg, LEVEL_3, "multi outs at %+F\n", node));
return 1;
}
- if(is_Conv(node)) {
+ if (is_Conv(node)) {
return get_conv_costs(get_Conv_op(node), dest_mode) - 1;
}
- if(is_optimizable_node(node)) {
- int i;
- int arity = get_irn_arity(node);
- int costs = 0;
-
- for(i = 0; i < arity; ++i) {
- ir_node *pred = get_irn_n(node, i);
- costs += get_conv_costs(pred, dest_mode);
- }
+ if (!is_optimizable_node(node)) {
+ return 1;
+ }
- return costs;
+ costs = 0;
+ arity = get_irn_arity(node);
+ for (i = 0; i < arity; ++i) {
+ ir_node *pred = get_irn_n(node, i);
+ costs += get_conv_costs(pred, dest_mode);
}
- return 1;
+ return costs;
+}
+
+static ir_node *place_conv(ir_node *node, ir_mode *dest_mode)
+{
+ ir_node *block = get_nodes_block(node);
+ ir_node *conv = new_r_Conv(current_ir_graph, block, node, dest_mode);
+ return conv;
}
static
return node;
if (is_Const(node)) {
- tarval *tv = tarval_convert_to(get_Const_tarval(node), dest_mode);
- assert(get_tarval_mode(tv) == dest_mode);
- return new_Const(dest_mode, tv);
+ /* TODO tarval module is incomplete and can't convert floats to ints */
+ tarval *tv = conv_const_tv(node, dest_mode);
+ if (tv == tarval_bad) {
+ return place_conv(node, dest_mode);
+ } else {
+ return new_Const(dest_mode, tv);
+ }
}
- if (!is_optimizable_node(node) || get_irn_n_edges(node) > 1) {
- ir_node *block = get_nodes_block(node);
- ir_node *conv = new_r_Conv(current_ir_graph, block, node, dest_mode);
- return conv;
+ if (get_irn_n_edges(node) > 1) {
+ return place_conv(node, dest_mode);
}
- if (is_Conv(node))
+ if (is_Conv(node)) {
return conv_transform(get_Conv_op(node), dest_mode);
+ }
+
+ if (!is_optimizable_node(node)) {
+ return place_conv(node, dest_mode);
+ }
arity = get_irn_arity(node);
for (i = 0; i < arity; i++) {
static
int is_downconv(ir_mode *src_mode, ir_mode *dest_mode)
{
- if(!mode_is_int(src_mode) || !mode_is_int(dest_mode))
- return 0;
- if(get_mode_size_bits(dest_mode) >= get_mode_size_bits(src_mode))
- return 0;
-
- return 1;
+ return
+ mode_is_int(src_mode) &&
+ mode_is_int(dest_mode) &&
+ get_mode_size_bits(dest_mode) < get_mode_size_bits(src_mode);
}
/* TODO, backends can't handle and it's probably not more efficient on most
}
#endif
+static char changed;
+
static
void conv_opt_walker(ir_node *node, void *data)
{
}
#endif
- if(!is_Conv(node))
+ if (!is_Conv(node))
return;
pred = get_Conv_op(node);
mode = get_irn_mode(node);
pred_mode = get_irn_mode(pred);
- if(!is_downconv(pred_mode, mode))
+ if (!is_Phi(pred) && !is_downconv(pred_mode, mode))
return;
- costs = get_conv_costs(pred, mode);
+ /* - 1 for the initial conv */
+ costs = get_conv_costs(pred, mode) - 1;
DB((dbg, LEVEL_2, "Costs for %+F -> %+F: %d\n", node, pred, costs));
if (costs >= 0) return;
transformed = conv_transform(pred, mode);
exchange(node, transformed);
+ changed = 1;
}
void conv_opt(ir_graph *irg)
DB((dbg, LEVEL_1, "===> Performing conversion optimization on %+F\n", irg));
edges_assure(irg);
- irg_walk_graph(irg, conv_opt_walker, NULL, NULL);
+ do {
+ changed = 0;
+ irg_walk_graph(irg, NULL, conv_opt_walker, NULL);
+ local_optimize_graph(irg);
+ } while (changed);
}
projects / libfirm / blobdiff