/*
- * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
+ * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
*
* This file is part of libFirm.
*
#include "iredges_t.h"
#include "irgwalk.h"
#include "irprintf.h"
+#include "irgopt.h"
+#include "irtools.h"
/**
* Walker environment.
*/
typedef struct _env_t {
- unsigned num_confirms; /**< number of inserted Confirm nodes */
- unsigned num_consts; /**< number of constants placed */
- unsigned num_eq; /**< number of equalities placed */
+ unsigned num_confirms; /**< number of inserted Confirm nodes */
+ unsigned num_consts; /**< number of constants placed */
+ unsigned num_eq; /**< number of equalities placed */
} env_t;
/**
* 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);
+ if (is_Phi(node)) {
+ /* the effective use of a Phi argument is in its predecessor block */
+ node = get_nodes_block(node);
+ return get_Block_cfgpred_block(node, pos);
+ }
+ return get_nodes_block(node);
}
/**
}
} /* 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 introduce 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);
+ }
+ }
+ }
+}
+
/**
* Handle an IF-branch.
*
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))
+ if (is_Bad(left) || is_Bad(right))
return;
op = get_irn_op(left);
* 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 *succ = get_edge_src_irn(edge);
+ ir_node *user = get_edge_src_irn(edge);
int pos = get_edge_src_pos(edge);
- ir_node *blk = get_effective_use_block(succ, pos);
+ ir_node *blk = get_effective_use_block(user, pos);
next = get_irn_out_edge_next(left, edge);
if (block_dominates(block, blk)) {
* dominated by the branch block.
* We can replace the input with right.
*/
- set_irn_n(succ, pos, 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, succ, 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 */
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);
+// ir_printf("3 Replacing input %d of node %n with %n\n", pos, user, c);
env->num_confirms += 1;
}
return;
proj = get_Block_cfgpred(block, 0);
- if (get_irn_op(proj) != op_Proj)
+ if (! is_Proj(proj))
return;
cond = get_Proj_pred(proj);
- if (get_irn_op(cond) != op_Cond)
+ if (! is_Cond(cond))
return;
selector = get_Cond_selector(cond);
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)
+ if (! is_Proj(selector))
return;
cmp = get_Proj_pred(selector);
- if (get_irn_op(cmp) != op_Cmp)
+ if (! is_Cmp(cmp))
return;
pnc = get_Proj_proj(selector);
env_t env;
int edges_active = edges_activated(irg);
+ remove_critical_cf_edges(irg);
+
/* we need dominance info */
assure_doms(irg);
edges_deactivate(irg);
} /* construct_confirms */
+#if 0
/**
* Post-walker: Remove Confirm nodes
*/
static void rem_Confirm(ir_node *n, void *env) {
(void) env;
- if (get_irn_op(n) == op_Confirm) {
+ if (is_Confirm(n)) {
ir_node *value = get_Confirm_value(n);
if (value != n)
exchange(n, value);
}
}
} /* rem_Confirm */
+#endif
/*
* 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 */
projects / libfirm / blobdiff