/*
- * 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) 1995-2008 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 "iredges_t.h"
#include "irgwalk.h"
#include "irprintf.h"
+#include "irgopt.h"
+#include "irtools.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) {
+ if (is_Phi(node)) {
+ /* the effective use of a Phi is in its predecessor block */
+ node = get_irn_n(node, pos);
+ }
+ return get_nodes_block(node);
+}
+
/**
* Handle a CASE-branch.
*
* Branch labels are a simple case. We can replace the value
* by a Const with the branch label.
*/
-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);
-
- next = get_irn_out_edge_next(irn, edge);
-
- if (block_dominates(block, blk)) {
- /*
- * Ok, we found a user of irn that is placed
- * in a block dominated by the branch block.
- * We can replace the input with the Constant
- * branch label.
- */
-
- if (! c) {
- ir_mode *mode = get_irn_mode(irn);
- 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;
- }
- }
+static void handle_case(ir_node *block, ir_node *irn, long nr, env_t *env) {
+ 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);
+ 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 (block_dominates(block, blk)) {
+ /*
+ * Ok, we found a user of irn that is placed
+ * in a block dominated by the branch block.
+ * We can replace the input with the Constant
+ * branch label.
+ */
+
+ if (! c) {
+ ir_mode *mode = get_irn_mode(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);
+ }
+
+ 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 a mode_b input of Cond nodes.
+ *
+ * @param block the block which is entered by the branch
+ * @param selector the mode_b node expressing the branch condition
+ * @param pnc the true/false condition branch
+ * @param env statistical environment
+ */
+static void handle_modeb(ir_node *block, ir_node *selector, pn_Cond pnc, env_t *env) {
+ ir_node *cond, *old, *cond_block, *other_blk = NULL, *con = NULL;
+ ir_node *c_b = NULL, *c_o = NULL;
+ const ir_edge_t *edge, *next;
+
+ for (edge = get_irn_out_edge_first(selector); edge; edge = next) {
+ ir_node *user = get_edge_src_irn(edge);
+ int pos = get_edge_src_pos(edge);
+ ir_node *user_blk = get_effective_use_block(user, pos);
+
+ next = get_irn_out_edge_next(selector, edge);
+ if (block_dominates(block, user_blk)) {
+ /*
+ * Ok, we found a usage of selector in a block
+ * dominated by the branch block.
+ * We can replace the input with true/false.
+ */
+ if (con == NULL) {
+ con = new_Const(mode_b, pnc == pn_Cond_true ? tarval_b_true : tarval_b_false);
+ }
+ old = get_irn_n(user, pos);
+ set_irn_n(user, pos, con);
+ DBG_OPT_CONFIRM_C(old, con);
+
+ // ir_printf("2 Replacing input %d of node %n with %n\n", pos, user, con);
+
+ env->num_consts += 1;
+ } else {
+ int i, n;
+
+ /* get the other block */
+ if (other_blk == NULL) {
+ /* we have already tested, that block has only ONE Cond predecessor */
+ cond = get_Proj_pred(get_Block_cfgpred(block, 0));
+ cond_block = get_nodes_block(cond);
+ foreach_out_edge(cond, edge) {
+ ir_node *proj = get_edge_src_irn(edge);
+ if (get_Proj_proj(proj) == (long)pnc)
+ continue;
+ edge = get_irn_out_edge_first(proj);
+ other_blk = get_edge_src_irn(edge);
+ break;
+ }
+ assert(other_blk);
+
+ /*
+ * Note the special case here: if block is a then, there might be no else
+ * block. In that case the other_block is the user_blk itself and pred_block
+ * is the cond_block ...
+ *
+ * Best would be to indroduce a block here, removing this critical edge.
+ * For some reasons I cannot repair dominance here, so I have to remove
+ * ALL critical edges...
+ * FIXME: This should not be needed if we could repair dominance ...
+ */
+ }
+
+ n = get_Block_n_cfgpreds(user_blk);
+
+ /*
+ * We have found a user in a non-dominated block:
+ * check, if all its block predecessors are dominated.
+ * If yes, place a Phi.
+ */
+ for (i = n - 1; i >= 0; --i) {
+ ir_node *pred_blk = get_Block_cfgpred_block(user_blk, i);
+
+ if (!block_dominates(block, pred_blk) &&
+ !block_dominates(other_blk, pred_blk)) {
+ /* can't do anything */
+ break;
+ }
+ }
+ if (i < 0) {
+ ir_node *phi, **in;
+
+ NEW_ARR_A(ir_node *, in, n);
+ /* ok, ALL predecessors are either dominated by block OR other block */
+ if (c_b == NULL) {
+ ir_node *c_true = new_Const(mode_b, tarval_b_true);
+ ir_node *c_false = new_Const(mode_b, tarval_b_false);
+ c_b = new_r_Confirm(current_ir_graph, cond_block, selector,
+ pnc == pn_Cond_true ? c_true : c_false, pn_Cmp_Eq);
+ c_o = new_r_Confirm(current_ir_graph, cond_block, selector,
+ pnc == pn_Cond_false ? c_true : c_false, pn_Cmp_Eq);
+ }
+ for (i = n - 1; i >= 0; --i) {
+ ir_node *pred_blk = get_Block_cfgpred_block(user_blk, i);
+
+ if (block_dominates(block, pred_blk))
+ in[i] = c_b;
+ else
+ in[i] = c_o;
+ }
+ phi = new_r_Phi(current_ir_graph, user_blk, n, in, mode_b);
+ set_irn_n(user, pos, phi);
+ }
+ }
+ }
}
/**
* @param pnc the Compare relation for taking this branch
* @param env statistical environment
*/
-static void handle_if(ir_node *block, ir_node *cmp, pn_Cmp pnc, env_t *env)
-{
- ir_node *left = get_Cmp_left(cmp);
- ir_node *right = get_Cmp_right(cmp);
+static void handle_if(ir_node *block, ir_node *cmp, pn_Cmp pnc, env_t *env) {
+ ir_node *left = get_Cmp_left(cmp);
+ ir_node *right = get_Cmp_right(cmp);
+ ir_node *cond_block;
ir_op *op;
- const ir_edge_t *edge, *next;
-
- /* Beware of Bads */
- if (is_Bad(left) ||is_Bad(right))
- return;
-
- op = get_irn_op(left);
-
- /* 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;
- right = t;
-
- pnc = get_inversed_pnc(pnc);
- }
-
- /*
- * First case: both values are identical.
- * replace the right one by the left 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);
-
- 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.
- * 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;
- 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);
-
- 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.
- * 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;
- }
- }
- }
-}
+ const ir_edge_t *edge, *next;
+
+ /* Beware of Bads */
+ if (is_Bad(left) || is_Bad(right))
+ return;
+
+ 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;
+ right = t;
+
+ pnc = get_inversed_pnc(pnc);
+ }
+
+ /*
+ * First case: both values are identical.
+ * replace the left one by the right (potentially const) one.
+ */
+ if (pnc == pn_Cmp_Eq) {
+ cond_block = get_Block_cfgpred_block(block, 0);
+ for (edge = get_irn_out_edge_first(left); edge; edge = next) {
+ ir_node *user = get_edge_src_irn(edge);
+ int pos = get_edge_src_pos(edge);
+ ir_node *blk = get_effective_use_block(user, pos);
+
+ next = get_irn_out_edge_next(left, edge);
+ if (block_dominates(block, blk)) {
+ /*
+ * Ok, we found a usage of left in a block
+ * dominated by the branch block.
+ * We can replace the input with right.
+ */
+ set_irn_n(user, pos, right);
+ DBG_OPT_CONFIRM(left, right);
+
+// ir_printf("2 Replacing input %d of node %n with %n\n", pos, user, right);
+
+ env->num_eq += 1;
+ } else if (block_dominates(blk, cond_block)) {
+ if (is_Const(right) && get_irn_pinned(user) == op_pin_state_floats) {
+ /*
+ * left == Const and we found a movable user of left in a
+ * dominator of the Cond block
+ */
+ const ir_edge_t *edge, *next;
+ for (edge = get_irn_out_edge_first(user); edge; edge = next) {
+ ir_node *usr_of_usr = get_edge_src_irn(edge);
+ int npos = get_edge_src_pos(edge);
+ ir_node *blk = get_effective_use_block(usr_of_usr, npos);
+
+ next = get_irn_out_edge_next(user, edge);
+ if (block_dominates(block, blk)) {
+ /*
+ * The user of the user is dominated by our true/false
+ * block. So, create a copy of user WITH the constant
+ * replacing it's pos'th input.
+ *
+ * This is always good for unop's and might be good
+ * for binops.
+ *
+ * If user has other user in the false/true block, code
+ * placement will move it down.
+ * If there are users in cond block or upper, we create
+ * "redundant ops", because one will have a const op,
+ * the other no const ...
+ */
+ ir_node *new_op = exact_copy(user);
+ set_nodes_block(new_op, block);
+ set_irn_n(new_op, pos, right);
+ set_irn_n(usr_of_usr, npos, new_op);
+ }
+ }
+ }
+ }
+ }
+ } 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);
+ 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 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, user, c);
+
+ env->num_confirms += 1;
+ }
+ }
+ }
+} /* handle_if */
/**
* Pre-walker: Called for every block to insert Confirm nodes
*/
-static void insert_Confirm(ir_node *block, void *env)
-{
- ir_node *cond, *proj, *selector;
- ir_mode *mode;
-
- /*
- * we can only handle blocks with only ONE control flow
- * predecessor
- */
- if (get_Block_n_cfgpreds(block) != 1)
- return;
-
- proj = get_Block_cfgpred(block, 0);
- if (get_irn_op(proj) != op_Proj)
- return;
-
- cond = get_Proj_pred(proj);
- if (get_irn_op(cond) != op_Cond)
- return;
-
- selector = get_Cond_selector(cond);
- mode = get_irn_mode(selector);
-
- if (mode == mode_b) {
- ir_node *cmp;
- pn_Cmp pnc;
-
- /* this should be an IF, check this */
- if (get_irn_op(selector) != op_Proj)
- return;
-
- cmp = get_Proj_pred(selector);
- if (get_irn_op(cmp) != op_Cmp)
- return;
-
- pnc = get_Proj_proj(selector);
-
- if (get_Proj_proj(proj) != pn_Cond_true) {
- /* 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)) {
- long proj_nr = get_Proj_proj(proj);
-
- /* this is a CASE, but we cannot handle the default case */
- if (proj_nr == get_Cond_defaultProj(cond))
- return;
-
- handle_case(block, get_Cond_selector(cond), proj_nr, env);
- }
-}
+static void insert_Confirm(ir_node *block, void *env) {
+ ir_node *cond, *proj, *selector;
+ ir_mode *mode;
+
+ /*
+ * we can only handle blocks with only ONE control flow
+ * predecessor yet.
+ */
+ if (get_Block_n_cfgpreds(block) != 1)
+ return;
+
+ proj = get_Block_cfgpred(block, 0);
+ if (! is_Proj(proj))
+ return;
+
+ cond = get_Proj_pred(proj);
+ if (! is_Cond(cond))
+ return;
+
+ selector = get_Cond_selector(cond);
+ mode = get_irn_mode(selector);
+
+ if (mode == mode_b) {
+ ir_node *cmp;
+ pn_Cmp pnc;
+
+ handle_modeb(block, selector, get_Proj_proj(proj), env);
+
+ /* this should be an IF, check this */
+ if (get_irn_op(selector) != op_Proj)
+ return;
+
+ cmp = get_Proj_pred(selector);
+ if (get_irn_op(cmp) != op_Cmp)
+ return;
+
+ pnc = get_Proj_proj(selector);
+
+ if (get_Proj_proj(proj) != pn_Cond_true) {
+ /* 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)) {
+ long proj_nr = get_Proj_proj(proj);
+
+ /* this is a CASE, but we cannot handle the default case */
+ if (proj_nr == get_Cond_defaultProj(cond))
+ return;
+
+ handle_case(block, get_Cond_selector(cond), proj_nr, env);
+ }
+} /* insert_Confirm */
/*
* Construct Confirm nodes
*/
-void construct_confirms(ir_graph *irg)
-{
- env_t env;
- int edges_active = edges_activated(irg);
+void construct_confirms(ir_graph *irg) {
+ env_t env;
+ int edges_active = edges_activated(irg);
- if (get_irg_dom_state(irg) != dom_consistent) {
- /* we need dominance info */
- compute_doms(irg);
- }
+ remove_critical_cf_edges(irg);
- assert(get_irg_pinned(irg) == op_pin_state_pinned &&
- "Nodes must be placed to insert Confirms");
+ /* we need dominance info */
+ assure_doms(irg);
- if (! edges_active) {
- /* We need edges */
- edges_activate(irg);
- }
+ assert(get_irg_pinned(irg) == op_pin_state_pinned &&
+ "Nodes must be placed to insert Confirms");
- env.num_confirms = 0;
- env.num_consts = 0;
- env.num_eq = 0;
+ if (! edges_active) {
+ /* We need edges */
+ edges_activate(irg);
+ }
- /* now, visit all blocks and add Confirms where possible */
- irg_block_walk_graph(irg, insert_Confirm, NULL, &env);
+ env.num_confirms = 0;
+ env.num_consts = 0;
+ env.num_eq = 0;
- if (env.num_confirms | env.num_consts | env.num_eq) {
- /* we have add nodes or changed DF edges */
- set_irg_outs_inconsistent(irg);
+ /* now, visit all blocks and add Confirms where possible */
+ irg_block_walk_graph(irg, insert_Confirm, NULL, &env);
- /* the new nodes are not in the loop info */
- set_irg_loopinfo_inconsistent(irg);
- }
+ if (env.num_confirms | env.num_consts | env.num_eq) {
+ /* we have add nodes or changed DF edges */
+ set_irg_outs_inconsistent(irg);
+
+ /* the new nodes are not in the loop info */
+ set_irg_loopinfo_inconsistent(irg);
+ }
#if 0
- printf("# Confirms inserted : %u\n", env.num_confirms);
- printf("# Const replacements: %u\n", env.num_consts);
- printf("# node equalities : %u\n", env.num_eq);
+ printf("# Confirms inserted : %u\n", env.num_confirms);
+ printf("# Const replacements: %u\n", env.num_consts);
+ printf("# node equalities : %u\n", env.num_eq);
#endif
- /* deactivate edges if they where off */
- if (! edges_active)
- edges_deactivate(irg);
-}
+ /* deactivate edges if they where off */
+ if (! edges_active)
+ edges_deactivate(irg);
+} /* construct_confirms */
/**
* Post-walker: Remove Confirm nodes
*/
static void rem_Confirm(ir_node *n, void *env) {
- if (get_irn_op(n) == op_Confirm) {
- 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());
- }
- }
-}
+ (void) env;
+ if (get_irn_op(n) == op_Confirm) {
+ 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);
-}
+ set_opt_remove_confirm(1);
+ optimize_graph_df(irg);
+} /* remove_confirms */