GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
-Software Foundation; either version 2, or (at your option) any later
+Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
/* This pass implements tree level if-conversion transformation of loops.
Initial goal is to help vectorizer vectorize loops with conditions.
if (single_succ_p (bb))
{
basic_block bb_n = single_succ (bb);
- if (cond != NULL_TREE)
- add_to_predicate_list (bb_n, cond);
+
+ /* Successor bb inherits predicate of its predecessor. If there
+ is no predicate in predecessor bb, then consider successor bb
+ as always executed. */
+ if (cond == NULL_TREE)
+ cond = boolean_true_node;
+
+ add_to_predicate_list (bb_n, cond);
}
}
and it belongs to basic block BB.
PHI is not if-convertible
- if it has more than 2 arguments.
- - Virtual PHI is immediately used in another PHI node. */
+ - Virtual PHI is immediately used in another PHI node.
+ - Virtual PHI on BB other than header. */
static bool
if_convertible_phi_p (struct loop *loop, basic_block bb, tree phi)
{
imm_use_iterator imm_iter;
use_operand_p use_p;
+
+ if (bb != loop->header)
+ {
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Virtual phi not on loop header.\n");
+ return false;
+ }
FOR_EACH_IMM_USE_FAST (use_p, imm_iter, PHI_RESULT (phi))
{
if (TREE_CODE (USE_STMT (use_p)) == PHI_NODE)
/* Select condition that is not TRUTH_NOT_EXPR. */
tmp_cond = (first_edge->src)->aux;
+ gcc_assert (tmp_cond);
+
if (TREE_CODE (tmp_cond) == TRUTH_NOT_EXPR)
{
edge tmp_edge;
/* Replace phi nodes with cond. modify expr. */
for (i = 1; i < orig_loop_num_nodes; i++)
{
- tree phi, cond;
+ tree phi, cond = NULL_TREE;
block_stmt_iterator bsi;
basic_block true_bb = NULL;
bb = ifc_bbs[i];
/* Update stmt list. */
last = tsi_last (bb_stmt_list (merge_target_bb));
tsi_link_after (&last, bb_stmt_list (bb), TSI_NEW_STMT);
- set_bb_stmt_list (bb, NULL);
+ set_bb_stmt_list (bb, alloc_stmt_list());
delete_basic_block (bb);
}