/*
- * Project: libFIRM
- * File name: ir/ana/irconsconfirm.c
- * Purpose: Construction of Confirm nodes
- * Author: Michael Beck
- * Modified by:
- * Created: 6.2005
- * CVS-ID: $Id$
- * Copyright: (C) 2002-2005 Universität Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
+ * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
+ *
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
*/
/**
- * @file irconsconfirm.c
- *
- * Construction of Confirm nodes
- *
- * @author Michael Beck
+ * @file
+ * @brief Construction of Confirm nodes
+ * @author Michael Beck
+ * @date 6.2005
+ * @version $Id$
*/
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
#include "irgraph_t.h"
#include "irnode_t.h"
#include "ircons_t.h"
unsigned num_eq; /**< number of equalities placed */
} env_t;
+/**
+ * Return the effective use block of a node and it's predecessor on
+ * position pos.
+ *
+ * @param node the node
+ * @param pos the position of the used input
+ *
+ * This handles correctly Phi nodes.
+ */
+static ir_node *get_effective_use_block(ir_node *node, int pos)
+{
+ /* the effective use of a Phi is in its predecessor block */
+ if (is_Phi(node))
+ return get_nodes_block(get_irn_n(node, pos));
+ else
+ return get_nodes_block(node);
+}
+
/**
* Handle a CASE-branch.
*
*/
static void handle_case(ir_node *block, ir_node *irn, long nr, env_t *env)
{
- int pos;
const ir_edge_t *edge, *next;
ir_node *c = NULL;
for (edge = get_irn_out_edge_first(irn); edge; edge = next) {
ir_node *succ = get_edge_src_irn(edge);
- ir_node *blk = get_nodes_block(succ);
+ int pos = get_edge_src_pos(edge);
+ ir_node *blk = get_effective_use_block(succ, pos);
next = get_irn_out_edge_next(irn, edge);
c = new_r_Const_type(current_ir_graph, block, mode, tv, tp);
}
- pos = get_edge_src_pos(edge);
set_irn_n(succ, pos, c);
DBG_OPT_CONFIRM_C(irn, c);
// ir_printf("1 Replacing input %d of node %n with %n\n", pos, succ, c);
env->num_consts += 1;
}
}
-}
+} /* handle_case */
/**
* Handle an IF-branch.
/*
* First case: both values are identical.
- * replace the right one by the left one.
+ * replace the left one by the right (potentially const) one.
*/
if (pnc == pn_Cmp_Eq) {
- int pos;
-
for (edge = get_irn_out_edge_first(left); edge; edge = next) {
ir_node *succ = get_edge_src_irn(edge);
- ir_node *blk = get_nodes_block(succ);
+ int pos = get_edge_src_pos(edge);
+ ir_node *blk = get_effective_use_block(succ, pos);
next = get_irn_out_edge_next(left, edge);
if (block_dominates(block, blk)) {
/*
- * Ok, we found a user of right that is placed
- * in a block dominated by the branch block.
+ * Ok, we found a usage of left in a block
+ * dominated by the branch block.
* We can replace the input with right.
*/
- pos = get_edge_src_pos(edge);
set_irn_n(succ, pos, right);
DBG_OPT_CONFIRM(left, right);
}
}
}
- else { /* not == cases */
- int pos;
+ else { /* not pn_Cmp_Eq cases */
ir_node *c = NULL;
for (edge = get_irn_out_edge_first(left); edge; edge = next) {
ir_node *succ = get_edge_src_irn(edge);
- ir_node *blk = get_nodes_block(succ);
+ int pos = get_edge_src_pos(edge);
+ ir_node *blk = get_effective_use_block(succ, pos);
next = get_irn_out_edge_next(left, edge);
if (block_dominates(block, blk)) {
/*
- * Ok, we found a user of right that is placed
- * in a block dominated by the branch block.
+ * Ok, we found a usage of left in a block
+ * dominated by the branch block.
* We can replace the input with a Confirm(left, pnc, right).
*/
if (! c)
}
}
}
-}
+} /* handle_if */
/**
* Pre-walker: Called for every block to insert Confirm nodes
/*
* we can only handle blocks with only ONE control flow
- * predecessor
+ * predecessor yet.
*/
if (get_Block_n_cfgpreds(block) != 1)
return;
handle_case(block, get_Cond_selector(cond), proj_nr, env);
}
-}
+} /* insert_Confirm */
/*
* Construct Confirm nodes
/* deactivate edges if they where off */
if (! edges_active)
edges_deactivate(irg);
-}
+} /* construct_confirms */
/**
* Post-walker: Remove Confirm nodes
exchange(n, new_Bad());
}
}
-}
+} /* rem_Confirm */
/*
* Remove all Confirm nodes from a graph.
*/
void remove_confirms(ir_graph *irg) {
irg_walk_graph(irg, NULL, rem_Confirm, NULL);
-}
+} /* remove_confirms */
projects / libfirm / blobdiff