fixed some minor bugs

[libfirm] / ir / be / beifg_std.c

diff --git a/ir/be/beifg_std.c b/ir/be/beifg_std.c
index 28ca81d..8feeefa 100644 (file)
--- a/ir/be/beifg_std.c
+++ b/ir/be/beifg_std.c
@@ -200,6 +200,117 @@ static void ifg_std_neighbours_break(const void *self, void *iter)
        neighbours_break(iter, 1);
 }
 
+typedef struct _cliques_iter_t {
+       struct obstack ob;
+       const be_chordal_env_t *cenv;
+       ir_node **buf;
+       ir_node **blocks;
+       int n_blocks, blk;
+       struct list_head *bor;
+       pset *living;
+} cliques_iter_t;
+
+static INLINE void free_clique_iter(cliques_iter_t *it) {
+       it->n_blocks = -1;
+       obstack_free(&it->ob, NULL);
+       del_pset(it->living);
+}
+
+static void get_blocks_dom_order(ir_node *blk, void *env) {
+       cliques_iter_t *it = env;
+       obstack_ptr_grow(&it->ob, blk);
+}
+
+#define pset_foreach(pset, irn)  for(irn=pset_first(pset); irn; irn=pset_next(pset))
+
+
+/**
+ * NOTE: Be careful when changing this function!
+ *       First understand the control flow of consecutive calls.
+ */
+static INLINE int get_next_clique(cliques_iter_t *it) {
+
+       /* continue in the block we left the last time */
+       for (; it->blk < it->n_blocks; it->blk++) {
+               int output_on_shrink = 0;
+               struct list_head *head = get_block_border_head(it->cenv, it->blocks[it->blk]);
+
+               /* on entry to a new block set the first border ...
+               if (!it->bor)
+                       it->bor = head->prev;
+
+               /* ... otherwise continue with the border we left the last time */
+               for (; it->bor != head; it->bor = it->bor->prev) {
+                       border_t *b = list_entry(it->bor, border_t, list);
+
+                       /* if its a definition irn starts living */
+                       if (b->is_def) {
+                               pset_insert_ptr(it->living, b->irn);
+                               if (b->is_real)
+                                       output_on_shrink = 1;
+                       } else
+
+                       /* if its the last usage the irn dies */
+                       {
+                               /* before shrinking the set, return the current maximal clique */
+                               if (output_on_shrink) {
+                                       int count = 0;
+                                       ir_node *irn;
+
+                                       /* fill the output buffer */
+                                       pset_foreach(it->living, irn)
+                                               it->buf[count++] = irn;
+
+                                       assert(count > 0 && "We have a 'last usage', so there must be sth. in it->living");
+
+                                       return count;
+                               }
+
+                               pset_remove_ptr(it->living, b->irn);
+                       }
+               }
+
+               it->bor = NULL;
+               assert(0 == pset_count(it->living) && "Something has survived! (At the end of the block it->living must be empty)");
+       }
+
+       if (it->n_blocks != -1)
+               free_clique_iter(it);
+
+       return -1;
+}
+
+static int ifg_std_cliques_begin(const void *self, void *iter, ir_node **buf)
+{
+       const ifg_std_t *ifg = self;
+       cliques_iter_t *it = iter;
+       ir_node *start_bl = get_irg_start_block(it->cenv->irg);
+
+       obstack_init(&it->ob);
+       dom_tree_walk(start_bl, get_blocks_dom_order, NULL, it);
+
+       it->cenv     = ifg->env;
+       it->buf      = buf;
+       it->n_blocks = obstack_object_size(&it->ob) / sizeof(void *);
+       it->blocks   = obstack_finish(&it->ob);
+       it->blk      = 0;
+       it->bor      = NULL;
+       it->living   = pset_new_ptr(2 * arch_register_class_n_regs(it->cenv->cls));
+
+       return get_next_clique(it);
+}
+
+static int ifg_std_cliques_next(const void *self, void *iter)
+{
+       return get_next_clique(iter);
+}
+
+static void ifg_std_cliques_break(const void *self, void *iter)
+{
+       free_clique_iter(iter);
+}
+
+
 static int ifg_std_degree(const void *self, const ir_node *irn)
 {
        adj_iter_t it;
@@ -213,6 +324,7 @@ static int ifg_std_degree(const void *self, const ir_node *irn)
 static const be_ifg_impl_t ifg_std_impl = {
        sizeof(nodes_iter_t),
        sizeof(adj_iter_t),
+       sizeof(cliques_iter_t),
 
        ifg_std_free,
        ifg_std_connected,
@@ -222,6 +334,9 @@ static const be_ifg_impl_t ifg_std_impl = {
        ifg_std_nodes_begin,
        ifg_std_nodes_next,
        ifg_std_nodes_break,
+       ifg_std_cliques_begin,
+       ifg_std_cliques_next,
+       ifg_std_cliques_break,
        ifg_std_degree
 };