/**
* Creates a new Sequence region.
*/
-static ir_region *new_Sequence(struct obstack *obst, ir_region *nset[]) {
+static ir_region *new_Sequence(struct obstack *obst, ir_region *nset, int nset_len) {
ir_region *reg;
- int i, len = ARR_LEN(nset);
+ int i;
ALLOC_REG(obst, reg, ir_rk_Sequence);
- reg->nr = nset[0]->nr;
- reg->parts = CLONE_ARR_D(ir_reg_or_blk, obst, nset);
- reg->pred = DUP_ARR_D(ir_region *, obst, nset[0]->pred);
- reg->succ = DUP_ARR_D(ir_region *, obst, nset[len - 1]->succ);
+ reg->parts = NEW_ARR_D(ir_reg_or_blk, obst, nset_len);
- for (i = 0; i < len; ++i) {
- reg->parts[i].region = nset[i];
- nset[i]->parent = reg;
+ /* beware: list is in reverse order, reverse */
+ for (i = nset_len - 1; i >= 0; --i) {
+ reg->parts[i].region = nset;
+ nset->parent = reg;
+ nset = nset->link;
}
+ reg->nr = reg->parts[0].region->nr;
+ reg->pred = DUP_ARR_D(ir_region *, obst, reg->parts[0].region->pred);
+ reg->succ = DUP_ARR_D(ir_region *, obst, reg->parts[nset_len - 1].region->succ);
+
DEBUG_ONLY(
DB((dbg, LEVEL_2, " Created Sequence "));
- for (i = 0; i < len; ++i) {
+ for (i = 0; i < nset_len; ++i) {
DB((dbg, LEVEL_2, "(%u)", reg->parts[i].region->nr));
}
DB((dbg, LEVEL_2, "\n"));
/**
* Create a new Switch/case region.
*/
-static ir_region *new_SwitchCase(struct obstack *obst, ir_region_kind type, ir_region *head, ir_region *end, pset *cases) {
- ir_region *reg, *c;
+static ir_region *new_SwitchCase(struct obstack *obst, ir_region_kind type, ir_region *head, ir_region *exit,
+ ir_region *cases, int cases_len) {
+ ir_region *reg, *c, *n;
int i;
+ int add = 1;
+
+ /* check, if the exit block is in the list */
+ for (c = cases; c != NULL; c = c->link) {
+ if (c == exit) {
+ add = 0;
+ break;
+ }
+ }
ALLOC_REG(obst, reg, type);
reg->nr = head->nr;
- reg->parts = NEW_ARR_D(ir_reg_or_blk, obst, pset_count(cases) + 1);
+ reg->parts = NEW_ARR_D(ir_reg_or_blk, obst, cases_len + add);
reg->parts[0].region = head; head->parent = reg;
- i = 0;
- foreach_pset(cases, c) {
- reg->parts[i].region = c;
- c->parent = reg;
+ i = 1;
+ for (c = cases; c != NULL; c = n) {
+ n = c->link;
+ if (c != exit) {
+ reg->parts[i++].region = c;
+ c->parent = reg;
+ }
+ c->link = NULL;
}
reg->pred = DUP_ARR_D(ir_region *, obst, head->pred);
reg->succ = NEW_ARR_D(ir_region *, obst, 1);
- reg->succ[0] = end;
+ reg->succ[0] = exit;
- DB((dbg, LEVEL_2, " Created Switch(%u)Exit(%u)\n", reg->nr, end->nr));
-
- del_pset(cases);
+ DEBUG_ONLY(
+ DB((dbg, LEVEL_2, " Created %s(%u)\n", reg->type == ir_rk_Switch ? "Switch" : "Case", reg->nr));
+ for (i = 1; i < ARR_LEN(reg->parts); ++i) {
+ DB((dbg, LEVEL_2, " Case(%u)\n", reg->parts[i].region->nr));
+ }
+ DB((dbg, LEVEL_2, " Exit(%u)\n", exit->nr));
+ )
return reg;
} /* new_SwitchCase */
return NULL;
}
+/**
+ * Clear all links on a list. Needed, because we expect cleared links-
+ */
+static void clear_list(ir_region *list) {
+ ir_region *next;
+
+ for (next = list; next; list = next) {
+ next = list->link;
+ list->link = NULL;
+ }
+}
+
+#define ADD_LIST(list, n) do { n->link = list; list = n; ++list##_len; } while(0)
+
/**
* Detect an acyclic region.
*/
static ir_region *acyclic_region_type(struct obstack *obst, ir_region *node) {
ir_region *n, *m;
int p, s, i, k;
- ir_region **nset = NEW_ARR_F(ir_region *, 0);
- pset *set;
+ ir_region *nset = NULL;
+ int nset_len = 0;
ir_region *res;
/* check for a block containing node */
p = 1;
s = get_region_n_succs(n) == 1;
while (p & s) {
- ARR_APP1(ir_region *, nset, n);
+ ADD_LIST(nset, n);
n = get_region_succ(n, 0);
p = get_region_n_preds(n) == 1;
s = get_region_n_succs(n) == 1;
}
if (p) {
- ARR_APP1(ir_region *, nset, n);
+ ADD_LIST(nset, n);
}
- if (ARR_LEN(nset) >= 2) {
+ if (nset_len > 1) {
/* node --> .. --> .. */
- res = new_Sequence(obst, nset);
- DEL_ARR_F(nset);
+ res = new_Sequence(obst, nset, nset_len);
return res;
}
- DEL_ARR_F(nset);
node = n;
/* check for IfThenElse */
}
}
/* check for Switch, case */
- set = pset_new_ptr_default();
- p = k > 0;
- for (i = k - 1; i >= 0; --i) {
- n = get_region_succ(node, i);
- pset_insert_ptr(set, n);
- if (get_region_n_succs(n) != 1) {
- p = 0;
- break;
- }
- }
- if (p) {
- ir_region_kind kind = ir_rk_Case;
-
- m = pset_first(set);
- if (pset_find_ptr(set, m) != NULL) {
- /* must be a switch, if any, find the exit */
- kind = ir_rk_Switch;
-
- for (m = pset_next(set); m != NULL; m = pset_next(set)) {
- if (pset_find_ptr(set, m) == NULL) {
- pset_break(set);
+ if (k > 0) {
+ ir_region *exit = NULL;
+ nset = NULL; nset_len = 0;
+ p = 0;
+ for (i = k - 1; i >= 0; --i) {
+ n = get_region_succ(node, i);
+ ADD_LIST(nset, n);
+ if (get_region_n_succs(n) != 1) {
+ /* must be the exit */
+ exit = n;
+ ++p;
+ if (p > 1)
break;
- }
}
}
- if (m != NULL) {
- /* m ist the exit, do the checks */
- foreach_pset(set, n) {
- if (n == m) {
- /* good, switch to exit */
- continue;
- }
- if (pset_find_ptr(set, n) == NULL) {
- /* another exit */
- pset_break(set);
- break;
+ if (p <= 1) {
+ ir_region_kind kind = ir_rk_Case;
+ ir_region *pos_exit_1 = NULL;
+ ir_region *pos_exit_2 = NULL;
+
+ /* find the exit */
+ for (m = nset; m != NULL; m = m->link) {
+ if (get_region_n_succs(m) != 1) {
+ /* must be the exit block */
+ if (exit == NULL) {
+ exit = m;
+ } else if (exit != m) {
+ /* two exits */
+ exit = NULL;
+ break;
+ }
+ } else {
+ ir_region *succ = get_region_succ(m, 0);
+
+ if (succ->link == NULL) {
+ if (exit == NULL) {
+ if (succ == pos_exit_1)
+ exit = succ;
+ else if (succ == pos_exit_2)
+ exit = succ;
+ else if (pos_exit_1 == NULL)
+ pos_exit_1 = succ;
+ else if (pos_exit_2 == NULL)
+ pos_exit_2 = succ;
+ else {
+ /* more than two possible exits */
+ break;
+ }
+ } else if (exit != succ) {
+ /* two exits */
+ exit = NULL;
+ break;
+ }
+ }
}
- kind = ir_rk_Switch;
}
+ if (exit != NULL) {
+ /* do the checks */
+ for (n = nset; n != NULL; n = n->link) {
+ ir_region *succ;
+ if (n == exit) {
+ /* good, default fall through */
+ continue;
+ }
+ succ = get_region_succ(n, 0);
+ if (succ == exit) {
+ /* good, switch to exit */
+ continue;
+ }
+ if (succ->link == NULL) {
+ /* another exit */
+ break;
+ } else {
+ /* a fall through */
+ kind = ir_rk_Switch;
+ }
+ }
- if (n == NULL) {
- /* detected */
- return new_SwitchCase(obst, kind, node, m, set);
+ if (n == NULL) {
+ /* detected */
+ return new_SwitchCase(obst, kind, node, exit, nset, nset_len);
+ }
}
}
+ clear_list(nset);
}
- /* check for proper */
-
return NULL;
}
projects / libfirm / commitdiff