/*
- * 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"
#include "irgmod.h"
#include "iropt_dbg.h"
#include "iredges_t.h"
+#include "irgwalk.h"
+#include "irprintf.h"
/**
* Walker environment.
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.
*
* @param block the block which is entered by the branch
* @param irn the node expressing the switch value
- * @param pnc the branch label
+ * @param nr the branch label
* @param env statistical environment
*
* Branch labels are a simple case. We can replace the value
*/
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;
+ if (is_Bad(irn))
+ return;
+
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);
if (! c) {
ir_mode *mode = get_irn_mode(irn);
- type *tp = get_irn_type(irn);
+ ir_type *tp = get_irn_type(irn);
tarval *tv = new_tarval_from_long(nr, mode);
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.
{
ir_node *left = get_Cmp_left(cmp);
ir_node *right = get_Cmp_right(cmp);
+ ir_op *op;
const ir_edge_t *edge, *next;
- /* remove unordered if it's an integer compare */
- if (mode_is_int(get_irn_mode(left)))
- pnc &= ~pn_Cmp_Uo;
+ /* Beware of Bads */
+ if (is_Bad(left) ||is_Bad(right))
+ return;
- /* try to place the constant on the right side */
- if (get_irn_op(left) == op_Const) {
+ op = get_irn_op(left);
+
+ /* Do not create Confirm nodes for Cmp(Const, Const) constructs.
+ These are removed anyway */
+ if (op == op_Const && is_Const(right))
+ return;
+
+ /* try to place the constant on the right side for a Confirm */
+ if (op == op_Const || op == op_SymConst) {
ir_node *t = left;
left = right;
/*
* First case: both values are identical.
- * replace the left one by the right 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 left 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);
+// ir_printf("2 Replacing input %d of node %n with %n\n", pos, succ, right);
+
env->num_eq += 1;
}
}
}
- 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 left 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)
c = new_r_Confirm(current_ir_graph, block, left, right, pnc);
pos = get_edge_src_pos(edge);
set_irn_n(succ, pos, c);
+// ir_printf("3 Replacing input %d of node %n with %n\n", pos, succ, c);
env->num_confirms += 1;
}
}
}
-}
+} /* 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;
/* it's the false branch */
pnc = get_negated_pnc(pnc, mode);
}
+// ir_printf("At %n using %n Confirm %=\n", block, cmp, pnc);
+
handle_if(block, cmp, pnc, env);
}
else if (mode_is_int(mode)) {
handle_case(block, get_Cond_selector(cond), proj_nr, env);
}
-}
+} /* insert_Confirm */
/*
* Construct Confirm nodes
env_t env;
int edges_active = edges_activated(irg);
- if (get_irg_dom_state(irg) != dom_consistent) {
- /* we need dominance info */
- compute_doms(irg);
- }
+ /* we need dominance info */
+ assure_doms(irg);
+
+ assert(get_irg_pinned(irg) == op_pin_state_pinned &&
+ "Nodes must be placed to insert Confirms");
if (! edges_active) {
/* We need edges */
/* deactivate edges if they where off */
if (! edges_active)
edges_deactivate(irg);
-}
+} /* construct_confirms */
/**
- * Post-walker: Remove COnfirm nodes
+ * Post-walker: Remove Confirm nodes
*/
static void rem_Confirm(ir_node *n, void *env) {
if (get_irn_op(n) == op_Confirm) {
- exchange(n, get_Confirm_value(n));
+ ir_node *value = get_Confirm_value(n);
+ if (value != n)
+ exchange(n, value);
+ else {
+ /*
+ * Strange: a Confirm is it's own bound. This can happen
+ * in dead blocks when Phi nodes are already removed.
+ */
+ 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