#include "irnode_t.h"
#include "ircons_t.h"
#include "array.h"
+#include "iredges.h"
#define get_dom_info(bl) (&(bl)->attr.block.dom)
return 0;
}
+/* Returns the smallest common dominator block of two nodes. */
+ir_node *node_smallest_common_dominator(ir_node *a, ir_node *b)
+{
+ ir_node *bl_a = is_Block(a) ? a : get_nodes_block(a);
+ ir_node *bl_b = is_Block(b) ? b : get_nodes_block(b);
+ ir_node *dom_bl = NULL;
+
+ /* Check if block of a dominates block of b */
+ if (block_dominates(bl_a, bl_b))
+ dom_bl = bl_a;
+ /* Check if block of b dominates block of a */
+ else if (block_dominates(bl_b, bl_a))
+ dom_bl = bl_b;
+ else {
+ /* walk up dominator tree and search for first block dominating a and b */
+ while (! dom_bl) {
+ bl_a = get_Block_idom(bl_a);
+
+ assert(! is_Bad(bl_a) && "block is dead?");
+
+ if (block_dominates(bl_a, bl_b))
+ dom_bl = bl_a;
+ }
+ }
+
+ return dom_bl;
+}
+
+/* Returns the smallest common dominator block of all users of a node. */
+ir_node *node_users_smallest_common_dominator(ir_node *irn, int handle_phi)
+{
+ int n, j, i = 0, success;
+ ir_node **user_blocks, *dom_bl;
+ const ir_edge_t *edge;
+
+ assert(! is_Block(irn) && "WRONG USAGE of node_users_smallest_common_dominator");
+ assert(edges_activated(get_irn_irg(irn)) && "need edges activated");
+
+ n = get_irn_n_edges(irn);
+
+ /* get array to hold all block of the node users */
+ NEW_ARR_A(ir_node *, user_blocks, n);
+ foreach_out_edge(irn, edge) {
+ ir_node *src = get_edge_src_irn(edge);
+
+ if (is_Phi(src) && handle_phi) {
+ /* get the corresponding cfg predecessor block if phi handling requested */
+ j = get_edge_src_pos(edge);
+ assert(j >= 0 && "kaputt");
+ user_blocks[i++] = get_Block_cfgpred_block(get_nodes_block(src), j);
+ }
+ else
+ user_blocks[i++] = is_Block(src) ? src : get_nodes_block(src);
+ }
+
+ assert(i == n && "get_irn_n_edges probably broken");
+
+ /* in case of only one user: return the block of the user */
+ if (n == 1)
+ return user_blocks[0];
+
+ i = 0;
+ /* search the smallest block dominating all user blocks */
+ do {
+ dom_bl = node_smallest_common_dominator(user_blocks[i], user_blocks[i + 1]);
+ success = 1;
+
+ /* check if this block dominates all remaining blocks as well */
+ for (j = i + 2; j < n; j++) {
+ if (! block_dominates(dom_bl, user_blocks[j]))
+ success = 0;
+ }
+
+ if (success)
+ break;
+
+ /* inherit the dominator block of the first (i + 1) users */
+ user_blocks[++i] = dom_bl;
+ } while (i < n - 1);
+
+ assert(success && "no block found dominating all users");
+
+ return dom_bl;
+}
+
+
/* Get the first node in the list of nodes dominated by a given block. */
ir_node *get_Block_dominated_first(const ir_node *bl)
{
/* The root of the dominator tree should be the End block. */
ir_node *root = get_irg_end_block(irg);
- assert(irg->pdom_state == dom_consistent
+ assert(irg->pdom_state == dom_consistent
&& "The dominators of the irg must be consistent");
assert(root && "The end block of the graph is NULL?");
assert(get_pdom_info(root)->idom == NULL
* count the number of blocks and clears the post dominance info
*/
static void count_and_init_blocks_pdom(ir_node *bl, void *env) {
- int *n_blocks = (int *) env;
- (*n_blocks) ++;
+ int *n_blocks = (int *) env;
+ (*n_blocks) ++;
memset(get_pdom_info(bl), 0, sizeof(dom_info));
- set_Block_ipostdom(bl, NULL);
- set_Block_postdom_pre_num(bl, -1);
- set_Block_postdom_depth(bl, -1);
+ set_Block_ipostdom(bl, NULL);
+ set_Block_postdom_pre_num(bl, -1);
+ set_Block_postdom_depth(bl, -1);
}
/** temporary type used while constructing the dominator / post dominator tree. */
* Start block misses control dead blocks.
*/
static void init_tmp_dom_info(ir_node *bl, tmp_dom_info *parent,
- tmp_dom_info *tdi_list, int* used) {
+ tmp_dom_info *tdi_list, int *used, int n_blocks) {
tmp_dom_info *tdi;
int i;
mark_Block_block_visited(bl);
set_Block_dom_pre_num(bl, *used);
+ assert(*used < n_blocks);
tdi = &tdi_list[*used];
++(*used);
- tdi->semi = tdi;
- tdi->label = tdi;
+ tdi->semi = tdi;
+ tdi->label = tdi;
tdi->ancestor = NULL;
- tdi->bucket = NULL;
- tdi->parent = parent;
- tdi->block = bl;
+ tdi->bucket = NULL;
+ tdi->parent = parent;
+ tdi->block = bl;
/* Iterate */
for (i = get_Block_n_cfg_outs_ka(bl) - 1; i >= 0; --i) {
ir_node *pred = get_Block_cfg_out_ka(bl, i);
assert(is_Block(pred));
- init_tmp_dom_info(pred, tdi, tdi_list, used);
+ init_tmp_dom_info(pred, tdi, tdi_list, used, n_blocks);
}
}
* End block misses blocks in endless loops.
*/
static void init_tmp_pdom_info(ir_node *bl, tmp_dom_info *parent,
- tmp_dom_info *tdi_list, int* used) {
+ tmp_dom_info *tdi_list, int* used, int n_blocks) {
tmp_dom_info *tdi;
int i;
mark_Block_block_visited(bl);
set_Block_postdom_pre_num(bl, *used);
+ assert(*used < n_blocks);
tdi = &tdi_list[*used];
++(*used);
if (is_Bad(pred))
continue;
assert(is_Block(pred));
- init_tmp_pdom_info(pred, tdi, tdi_list, used);
+ init_tmp_pdom_info(pred, tdi, tdi_list, used, n_blocks);
}
/* Handle keep-alives. Note that the preprocessing
ir_node *pred = get_irn_n(end, i);
if (is_Block(pred))
- init_tmp_pdom_info(pred, tdi, tdi_list, used);
+ init_tmp_pdom_info(pred, tdi, tdi_list, used, n_blocks);
}
}
}
*
* - count the number of blocks
* - clear the dominance info
- * - remove block-keepalives of live blocks to reduce
+ * - remove Block-keepalives of live blocks to reduce
* the number of "phantom" block edges
*
* @param irg the graph
tdi_list = xcalloc(n_blocks, sizeof(tdi_list[0]));
/* We need the out data structure. */
- if (irg->outs_state != outs_consistent)
- compute_irg_outs(irg);
+ assure_irg_outs(irg);
/* this with a standard walker as passing the parent to the sons isn't
simple. */
used = 0;
inc_irg_block_visited(irg);
- init_tmp_dom_info(get_irg_start_block(irg), NULL, tdi_list, &used);
+ init_tmp_dom_info(get_irg_start_block(irg), NULL, tdi_list, &used, n_blocks);
/* If not all blocks are reachable from Start by out edges this assertion
fails.
assert(used == n_blocks && "Precondition for dom construction violated"); */
+ assert(used <= n_blocks && "Precondition for dom construction violated");
n_blocks = used;
ir_node *pred = get_irn_n(end, j);
tmp_dom_info *u;
- if (is_no_Block(pred))
- continue;
-
- if (get_Block_dom_pre_num(pred) == -1)
+ if (is_no_Block(pred) || get_Block_dom_pre_num(pred) == -1)
continue; /* control-dead */
u = dom_eval (&tdi_list[get_Block_dom_pre_num(pred)]);
set_Block_dom_depth(tdi_list[0].block, 1);
for (i = 1; i < n_blocks; i++) {
tmp_dom_info *w = &tdi_list[i];
+ int depth;
+
+ if (! w->dom)
+ continue; /* control dead */
if (w->dom != w->semi) w->dom = w->dom->dom;
set_Block_idom(w->block, w->dom->block);
- set_Block_dom_depth(w->block, get_Block_dom_depth(w->dom->block) + 1);
+
+ /* blocks dominated by dead one's are still dead */
+ depth = get_Block_dom_depth(w->dom->block);
+ if (depth > 0)
+ ++depth;
+ set_Block_dom_depth(w->block, depth);
}
/* clean up */
free(tdi_list);
- current_ir_graph = rem;
/* Do a walk over the tree and assign the tree pre orders. */
{
dom_tree_walk_irg(irg, assign_tree_dom_pre_order,
assign_tree_dom_pre_order_max, &tree_pre_order);
}
+ current_ir_graph = rem;
+}
+
+void assure_doms(ir_graph *irg) {
+ if (get_irg_dom_state(irg) != dom_consistent)
+ compute_doms(irg);
}
void free_dom(ir_graph *irg) {
tdi_list = xcalloc(n_blocks, sizeof(tdi_list[0]));
/* We need the out data structure. */
- if (irg->outs_state != outs_consistent)
- compute_irg_outs(irg);
+ assure_irg_outs(irg);
/* this with a standard walker as passing the parent to the sons isn't
simple. */
used = 0;
inc_irg_block_visited(irg);
- init_tmp_pdom_info(get_irg_end_block(irg), NULL, tdi_list, &used);
+ init_tmp_pdom_info(get_irg_end_block(irg), NULL, tdi_list, &used, n_blocks);
/* If not all blocks are reachable from End by cfg edges this assertion
fails.
assert(used == n_blocks && "Precondition for dom construction violated"); */
/* clean up */
free(tdi_list);
- irg = rem;
/* Do a walk over the tree and assign the tree pre orders. */
{
postdom_tree_walk_irg(irg, assign_tree_postdom_pre_order,
assign_tree_postdom_pre_order_max, &tree_pre_order);
}
+ current_ir_graph = rem;
+}
+
+void assure_postdoms(ir_graph *irg) {
+ if (get_irg_postdom_state(irg) != dom_consistent)
+ compute_postdoms(irg);
}
void free_postdom(ir_graph *irg) {
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