* @author Christoph Mallon, Matthias Braun
* @version $Id$
*/
-#ifdef HAVE_CONFIG_H
#include "config.h"
-#endif
#include "iroptimize.h"
#include <assert.h>
-#include "array.h"
+#include "array_t.h"
#include "debug.h"
#include "ircons.h"
#include "irgmod.h"
set_irn_in(node, n + 1, ins);
}
-static ir_node *search_def_and_create_phis(ir_node *block, ir_mode *mode)
+static ir_node *ssa_second_def;
+static ir_node *ssa_second_def_block;
+
+static ir_node *search_def_and_create_phis(ir_node *block, ir_mode *mode,
+ int first)
{
int i;
int n_cfgpreds;
if(is_Bad(block))
return new_Bad();
+ /* the other defs can't be marked for cases where a user of the original
+ * value is in the same block as the alternative definition.
+ * In this case we mustn't use the alternative definition.
+ * So we keep a flag that indicated wether we walked at least 1 block
+ * away and may use the alternative definition */
+ if (block == ssa_second_def_block && !first) {
+ return ssa_second_def;
+ }
+
/* already processed this block? */
if(irn_visited(block)) {
ir_node *value = (ir_node*) get_irn_link(block);
irg = get_irn_irg(block);
assert(block != get_irg_start_block(irg));
- /* a Blocks with only 1 predecessor need no Phi */
+ /* a Block with only 1 predecessor needs no Phi */
n_cfgpreds = get_Block_n_cfgpreds(block);
if(n_cfgpreds == 1) {
ir_node *pred_block = get_Block_cfgpred_block(block, 0);
- ir_node *value = search_def_and_create_phis(pred_block, mode);
+ ir_node *value = search_def_and_create_phis(pred_block, mode, 0);
set_irn_link(block, value);
mark_irn_visited(block);
/* set Phi predecessors */
for(i = 0; i < n_cfgpreds; ++i) {
ir_node *pred_block = get_Block_cfgpred_block(block, i);
- ir_node *pred_val = search_def_and_create_phis(pred_block, mode);
+ ir_node *pred_val = search_def_and_create_phis(pred_block, mode, 0);
set_irn_n(phi, i, pred_val);
}
* first value (the users are determined through the out-edges of the value).
* Uses the irn_visited flags. Works without using the dominance tree.
*/
-static void construct_ssa(ir_node * const *blocks, ir_node * const *vals, int n_vals)
+static void construct_ssa(ir_node *orig_block, ir_node *orig_val,
+ ir_node *second_block, ir_node *second_val)
{
- int i;
ir_graph *irg;
ir_mode *mode;
const ir_edge_t *edge;
const ir_edge_t *next;
- ir_node *value;
- assert(n_vals == 2);
+ /* no need to do anything */
+ if (orig_val == second_val)
+ return;
- irg = get_irn_irg(vals[0]);
+ irg = get_irn_irg(orig_val);
inc_irg_visited(irg);
- mode = get_irn_mode(vals[0]);
- for(i = 0; i < n_vals; ++i) {
- ir_node *value = vals[i];
- ir_node *value_block = blocks[i];
+ mode = get_irn_mode(orig_val);
+ set_irn_link(orig_block, orig_val);
+ mark_irn_visited(orig_block);
- assert(get_irn_mode(value) == mode || is_Bad(value));
-
- set_irn_link(value_block, value);
- mark_irn_visited(value_block);
- }
+ ssa_second_def_block = second_block;
+ ssa_second_def = second_val;
/* Only fix the users of the first, i.e. the original node */
- value = vals[0];
-
- foreach_out_edge_safe(value, edge, next) {
+ foreach_out_edge_safe(orig_val, edge, next) {
ir_node *user = get_edge_src_irn(edge);
int j = get_edge_src_pos(edge);
ir_node *user_block = get_nodes_block(user);
if (is_End(user))
continue;
- if (user_block == blocks[1])
- continue;
-
DB((dbg, LEVEL_3, ">>> Fixing user %+F (pred %d == %+F)\n", user, j, get_irn_n(user, j)));
if(is_Phi(user)) {
ir_node *pred_block = get_Block_cfgpred_block(user_block, j);
- newval = search_def_and_create_phis(pred_block, mode);
+ newval = search_def_and_create_phis(pred_block, mode, 1);
} else {
- newval = search_def_and_create_phis(user_block, mode);
+ newval = search_def_and_create_phis(user_block, mode, 1);
}
/* don't fix newly created Phis from the SSA construction */
} else {
new_pred = copy_and_fix_node(env, block, copy_block, j, pred);
}
+ DB((dbg, LEVEL_2, ">> Set Pred of %+F to %+F\n", copy, new_pred));
set_irn_n(copy, i, new_pred);
}
}
/* fix data-flow (and reconstruct SSA if needed) */
foreach_out_edge(block, edge) {
- ir_node *vals[2];
- ir_node *blocks[2];
ir_node *node = get_edge_src_irn(edge);
+ ir_node *copy_node;
ir_mode *mode;
if (is_Block(node)) {
DB((dbg, LEVEL_2, ">> Fixing users of %+F\n", node));
- blocks[0] = block;
- vals[0] = node;
- blocks[1] = copy_block;
- vals[1] = get_irn_link(node);
- construct_ssa(blocks, vals, 2);
+ copy_node = get_irn_link(node);
+ construct_ssa(block, node, copy_block, copy_node);
}
}
{
ir_node *block = get_nodes_block(jump);
- if (irn_visited(value))
+ if (irn_visited_else_mark(value))
return NULL;
- mark_irn_visited(value);
if (is_Const_or_Confirm(value)) {
if (eval_cmp(env, value) <= 0) {
{
ir_node *block = get_nodes_block(jump);
- if(irn_visited(value)) {
+ if (irn_visited_else_mark(value)) {
return NULL;
}
- mark_irn_visited(value);
if (is_Const_or_Confirm(value)) {
tarval *tv = get_Const_or_Confirm_tarval(value);
* to call optimize_df() an dead code. */
optimize_cf(irg);
}
-
}
projects / libfirm / blobdiff