* @file
* @brief Dead node elimination
* @author Michael Beck, Goetz Lindenmaier
- * @version $Id: opt_inline.c 27265 2010-03-07 15:13:00Z matze $
*
* Strictly speaking dead node elimination is unnecessary in firm - everthying
* which is not used can't be found by any walker.
#include "iroptimize.h"
#include "irnode_t.h"
#include "irgraph_t.h"
-#include "irphase_t.h"
#include "iredges_t.h"
#include "irhooks.h"
#include "irtools.h"
#include "irpass.h"
#include "pmap.h"
-/** a pointer to the new phases */
-static ir_phase *new_phases[PHASE_LAST + 1];
-
/**
* Reroute the inputs of a node from nodes in the old graph to copied nodes in
* the new graph
static void copy_node_dce(ir_node *node, void *env)
{
- int i;
ir_node *new_node = exact_copy(node);
ir_graph *irg = get_irn_irg(new_node);
(void) env;
/* preserve the node numbers for easier debugging */
new_node->node_nr = node->node_nr;
- /* copy phase information for this node */
- for (i = 0; i <= PHASE_LAST; i++) {
- ir_phase *phase = irg_get_phase(irg, i);
- if (phase == NULL)
- continue;
- if (!phase_get_irn_data(phase, node))
- continue;
- phase_set_irn_data(new_phases[i], new_node,
- phase_get_irn_data(phase, node));
- }
-
set_irn_link(node, new_node);
hook_dead_node_elim_subst(irg, node, new_node);
}
*/
static void copy_graph_env(ir_graph *irg)
{
+ ir_node *anchor = irg->anchor;
ir_node *new_anchor;
- int i;
-
- /* init the new_phases array */
- /* TODO: this is wrong, it should only allocate a new data_ptr inside
- * the phase! */
- for (i = 0; i <= PHASE_LAST; i++) {
- ir_phase *old_ph = irg_get_phase(irg, i);
- if (old_ph == NULL) {
- new_phases[i] = NULL;
- } else {
- new_phases[i] = new_phase(irg, old_ph->data_init);
- new_phases[i]->priv = old_ph->priv;
- }
- }
/* copy nodes */
- irg_walk_anchors(irg, copy_node_dce, rewire_inputs, NULL);
+ irg_walk_in_or_dep(anchor, copy_node_dce, rewire_inputs, NULL);
/* fix the anchor */
- new_anchor = get_irn_link(irg->anchor);
+ new_anchor = (ir_node*)get_irn_link(anchor);
assert(new_anchor != NULL);
irg->anchor = new_anchor;
-
- /* copy the new phases into the irg */
- for (i = 0; i <= PHASE_LAST; i++) {
- ir_phase *old_ph = irg_get_phase(irg, i);
- if (old_ph == NULL)
- continue;
-
- /* Matze: commented out for now: This is a memory leak, but for a real
- * fix we must not create new phases here, but reuse the old phases
- * and just create a new data array */
- /* phase_free(old_ph); */
- irg->phases[i] = new_phases[i];
- }
}
/**
free_irg_outs(irg);
free_trouts();
free_loop_information(irg);
- set_irg_doms_inconsistent(irg);
+ free_vrp_data(irg);
+ clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_DOMINANCE);
/* A quiet place, where the old obstack can rest in peace,
until it will be cremated. */
{
return def_graph_pass(name ? name : "dce", dead_node_elimination);
}
-
-
-/*
- __ _ __ __
- (_ __ o _ | \/ |_
- __)|_| | \_/ | \_/(/_ |_/\__|__
-
- The following stuff implements a facility that automatically patches
- registered ir_node pointers to the new node when a dead node elimination
- occurs.
-
- Warning: This is considered a hack - try hard to avoid this!
-*/
-
-struct survive_dce_t {
- struct obstack obst;
- pmap *places;
- pmap *new_places;
- hook_entry_t dead_node_elim;
- hook_entry_t dead_node_elim_subst;
-};
-
-typedef struct survive_dce_list_t {
- struct survive_dce_list_t *next;
- ir_node **place;
-} survive_dce_list_t;
-
-static void dead_node_hook(void *context, ir_graph *irg, int start)
-{
- survive_dce_t *sd = context;
- (void) irg;
-
- /* Create a new map before the dead node elimination is performed. */
- if (start) {
- sd->new_places = pmap_create_ex(pmap_count(sd->places));
- } else {
- /* Patch back all nodes if dead node elimination is over and something is to be done. */
- pmap_destroy(sd->places);
- sd->places = sd->new_places;
- sd->new_places = NULL;
- }
-}
-
-/**
- * Hook called when dead node elimination replaces old by nw.
- */
-static void dead_node_subst_hook(void *context, ir_graph *irg, ir_node *old, ir_node *nw)
-{
- survive_dce_t *sd = context;
- survive_dce_list_t *list = pmap_get(sd->places, old);
- (void) irg;
-
- /* If the node is to be patched back, write the new address to all registered locations. */
- if (list) {
- survive_dce_list_t *p;
-
- for (p = list; p; p = p->next)
- *(p->place) = nw;
-
- pmap_insert(sd->new_places, nw, list);
- }
-}
-
-/**
- * Make a new Survive DCE environment.
- */
-survive_dce_t *new_survive_dce(void)
-{
- survive_dce_t *res = XMALLOC(survive_dce_t);
- obstack_init(&res->obst);
- res->places = pmap_create();
- res->new_places = NULL;
-
- res->dead_node_elim.hook._hook_dead_node_elim = dead_node_hook;
- res->dead_node_elim.context = res;
- res->dead_node_elim.next = NULL;
-
- res->dead_node_elim_subst.hook._hook_dead_node_elim_subst = dead_node_subst_hook;
- res->dead_node_elim_subst.context = res;
- res->dead_node_elim_subst.next = NULL;
-
- register_hook(hook_dead_node_elim, &res->dead_node_elim);
- register_hook(hook_dead_node_elim_subst, &res->dead_node_elim_subst);
- return res;
-}
-
-/**
- * Free a Survive DCE environment.
- */
-void free_survive_dce(survive_dce_t *sd)
-{
- obstack_free(&sd->obst, NULL);
- pmap_destroy(sd->places);
- unregister_hook(hook_dead_node_elim, &sd->dead_node_elim);
- unregister_hook(hook_dead_node_elim_subst, &sd->dead_node_elim_subst);
- xfree(sd);
-}
-
-/**
- * Register a node pointer to be patched upon DCE.
- * When DCE occurs, the node pointer specified by @p place will be
- * patched to the new address of the node it is pointing to.
- *
- * @param sd The Survive DCE environment.
- * @param place The address of the node pointer.
- */
-void survive_dce_register_irn(survive_dce_t *sd, ir_node **place)
-{
- if (*place != NULL) {
- ir_node *irn = *place;
- survive_dce_list_t *curr = pmap_get(sd->places, irn);
- survive_dce_list_t *nw = OALLOC(&sd->obst, survive_dce_list_t);
-
- nw->next = curr;
- nw->place = place;
-
- pmap_insert(sd->places, irn, nw);
- }
-}
projects / libfirm / blobdiff