#include "iredges_t.h"
#include "irgwalk.h"
#include "irprintf.h"
+#include "irgopt.h"
+#include "irtools.h"
/**
* Walker environment.
* 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 is in its predecessor block */
+ node = get_irn_n(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 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);
+ }
+ }
+ }
+}
+
/**
* Handle an IF-branch.
*
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);
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)
return;
env_t env;
int edges_active = edges_activated(irg);
+ remove_critical_cf_edges(irg);
+
/* we need dominance info */
assure_doms(irg);
* 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