/** Detect basic iteration variables.
*
* The variable ir represented by a subgraph as this:
- * @verbatim
*
* init
* /|\
* | |
* |-->op
*
- * @endverbatim
* Where op is a Add or Sub, and init is loop invariant.
- *
- * @todo
- * So far we only accept Phi nodes with two predecessors.
+ * @@@ So far we only accept Phi nodes with two predecessors.
* We could expand this to Phi nodes where all preds are either
* op or loop invariant.
*
+ * @param n A phi node.
* @param info After call contains the induction variable information.
*/
+
induct_var_info *is_induction_variable (induct_var_info *info) {
int i;
- int op_pred, Store_in_op, Store_in_phi;
- ir_node *cmp_pred_bl, *cond_succ_true, *cond_succ_false, *cmp_const;
- ir_node *loop_head;
- ir_node *cmp_const_block;
+ int op_pred, Store_in_op, Store_in_phi, cmp_in_phi;
info->c = NULL;
info->cmp = NULL;
op_pred = get_irn_n_outs(info->op);
Store_in_op = 0;
Store_in_phi = 0;
+ cmp_in_phi = 0;
+ for (i = 0; i < op_pred; ++i){
+ ir_node *out = get_irn_out(info->op, i);
+ ir_op *out_op = get_irn_op(out);
+ if (out_op == op_Store)
+ Store_in_op++;
+ }
/* Information about loop of itervar_phi. */
info->l_itervar_phi = get_irn_loop(get_nodes_block(info->itervar_phi));
iter_var to reduce and marks if the iter_var have a Store
successor or a successor out of loop.*/
info->phi_pred = get_irn_n_outs(info->itervar_phi);
- loop_head = get_nodes_block(info->itervar_phi);
-
- for (i = 0; i < info->phi_pred; i++) {
+ for (i = 0; i < info->phi_pred; ++i) {
ir_node *out = get_irn_out(info->itervar_phi, i);
ir_op *out_op = get_irn_op(out);
+
if ((get_irn_loop(get_nodes_block(out)) != info->l_itervar_phi) &&
( get_Block_dom_depth(get_nodes_block(out)) >
get_Block_dom_depth(get_nodes_block(info->itervar_phi))))
if (out_op == op_Store)
Store_in_phi++;
- else {
- if (out_op == op_Cmp && !is_loop_invariant(out, loop_head)){
- cmp_pred_bl = get_irn_out(out, 0);
- cmp_pred_bl = get_irn_out(cmp_pred_bl, 0);
- cond_succ_true = get_irn_out(cmp_pred_bl, 1);
- cond_succ_false = get_irn_out(cmp_pred_bl, 0);
- if(is_loop_invariant(get_irn_out(cond_succ_false, 0), loop_head) ||
- is_loop_invariant(get_irn_out(cond_succ_true, 0), loop_head)){
- if (get_Cmp_left(out) == info->itervar_phi)
- cmp_const = get_Cmp_right(out);
- else
- cmp_const = get_Cmp_left(out);
- } else
- continue;
- if (info->cmp == NULL) {
- info->cmp = out;
- info->cmp_const = cmp_const;
- } else {
- info->cmp = NULL;
- return NULL;
- }
- }
+ else if (out_op == op_Cmp){
+ info->cmp = out;
+ cmp_in_phi++;
}
}
- for (i = 0; i < op_pred; ++i){
- ir_node *out = get_irn_out(info->op, i);
- ir_op *out_op = get_irn_op(out);
-
- if (out_op == op_Store)
- Store_in_op++;
- else {
- if (out_op == op_Cmp && !is_loop_invariant(out, loop_head)){
- cmp_pred_bl = get_irn_out(out, 0);
- cmp_pred_bl = get_irn_out(cmp_pred_bl, 0);
- cond_succ_true = get_irn_out(cmp_pred_bl, 1);
- cond_succ_false = get_irn_out(cmp_pred_bl, 0);
- if(is_loop_invariant(get_irn_out(cond_succ_false, 0), loop_head) ||
- is_loop_invariant(get_irn_out(cond_succ_true, 0), loop_head)){
- if (get_Cmp_left(out) == info->op)
- cmp_const = get_Cmp_right(out);
- else
- cmp_const = get_Cmp_left(out);
- } else
- continue;
- if (info->cmp == NULL) {
- info->cmp = out;
- info->cmp_const = cmp_const;
- set_irn_link(info->cmp_const, (void *) 1);
- } else {
- info->cmp = NULL;
- return NULL;
- }
- }
- }
- }
-
-
- if((info->phi_pred == 3 && op_pred == 1 && Store_in_phi == 0 && info->cmp != NULL) ||
+ if((info->phi_pred == 3 && op_pred == 1 && Store_in_phi == 0 && cmp_in_phi == 1) ||
(info->phi_pred == 2 && op_pred == 2 && Store_in_op == 0 && info->cmp != NULL ) ||
(info->phi_pred == 1 && Store_in_op == 0))
info->reducible = 1;
// Search for loop invariant of Cmp.
- if(info->cmp != NULL){
- cmp_const_block = get_nodes_block(info->cmp_const);
- if (get_Block_dom_depth(get_nodes_block(info->init)) >=
- get_Block_dom_depth(cmp_const_block))
- info->cmp_init_block = get_nodes_block(info->init);
- else
- info->cmp_init_block = cmp_const_block;
- }
- return info;
+ if (info->cmp != NULL) {
+ ir_node *cmp_const_block;
+
+ if (get_Cmp_left(info->cmp) == info->itervar_phi)
+ info->cmp_const = get_Cmp_right(info->cmp);
+ else
+ info->cmp_const = get_Cmp_left(info->cmp);
+
+ cmp_const_block = get_nodes_block(info->cmp_const);
+ if (get_Block_dom_depth(get_nodes_block(info->init)) >=
+ get_Block_dom_depth(cmp_const_block))
+ info->cmp_init_block = get_nodes_block(info->init);
+ else
+ info->cmp_init_block = cmp_const_block;
+ }
+ return info;
}
/**
*/
static int reduce(ir_node *reduce_var, induct_var_info *ivi)
{
- /* Essential conditions for a reducible node. */
+ // Essential conditions for a reducable node.
if (get_irn_loop(get_nodes_block(reduce_var)) != ivi->l_itervar_phi)
return 0;
ir_node *mul_init = NULL;
ir_node *mul_const = NULL;
- /* Search for constant and init of strong. */
+ // Search for constant and init of strong.
ir_node *mul_right = get_Mul_right(reduce_var);
ir_node *mul_left = get_Mul_left(reduce_var);
ir_op *mul_right_op = get_irn_op(mul_right);
if (! ivi->reducible){
int reduce_var_pred;
- /* Essential condition for the constant of strong. */
+ // Essential condition for the constant of strong.
if (get_Block_dom_depth(get_nodes_block(mul_const)) >=
get_Block_dom_depth(get_nodes_block(ivi->itervar_phi)))
return 0;
ivi->cmp_const, mul_const, get_irn_mode(mul_const));
ivi->increment = new_r_Mul (current_ir_graph, block_init,
ivi->increment, mul_const, get_irn_mode(mul_const));
- } else {
+ }else {
ivi->new_init = new_r_Mul (current_ir_graph, get_nodes_block(ivi->init),
mul_const, ivi->new_init,
get_irn_mode(mul_const));
return 1;
}
- } else if (get_irn_op (reduce_var) == op_Add) {
+ }else if (get_irn_op (reduce_var) == op_Add){
ir_node *add_init = NULL;
ir_node *add_const = NULL;
/* Call algorithm that computes the dominator trees. */
compute_doms(irg);
/* Call algorithm that computes the out edges */
- compute_outs(irg);
+ compute_irg_outs(irg);
/* -- Search expressions that can be optimized -- */
irg_walk_graph(irg, NULL, reduce_itervar, NULL);
projects / libfirm / blobdiff