diff options
| -rw-r--r-- | gcc/ChangeLog | 8 | ||||
| -rw-r--r-- | gcc/cfgloop.c | 70 | ||||
| -rw-r--r-- | gcc/cfgloop.h | 1 | ||||
| -rw-r--r-- | gcc/omp-low.c | 1 |
4 files changed, 60 insertions, 20 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b2efa82..82d23c0 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2015-11-25 Tom de Vries <tom@codesourcery.com> + + * cfgloop.c (find_single_latch): New function, factored out of ... + (flow_loops_find): ... here. + (verify_loop_structure): Improve verification of loop->latch. + * cfgloop.h (find_single_latch): Declare. + * omp-low.c (expand_omp_for_generic): Initialize latch of orig_loop. + 2015-11-25 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE> * config/sol2.h (SUPPORTS_INIT_PRIORITY): Move up. diff --git a/gcc/cfgloop.c b/gcc/cfgloop.c index 83a5262..e7cb78a 100644 --- a/gcc/cfgloop.c +++ b/gcc/cfgloop.c @@ -388,6 +388,33 @@ bb_loop_header_p (basic_block header) return false; } +/* Return the latch block for this header block, if it has just a single one. + Otherwise, return NULL. */ + +basic_block +find_single_latch (struct loop* loop) +{ + basic_block header = loop->header; + edge_iterator ei; + edge e; + basic_block latch = NULL; + + FOR_EACH_EDGE (e, ei, header->preds) + { + basic_block cand = e->src; + if (!flow_bb_inside_loop_p (loop, cand)) + continue; + + if (latch != NULL) + /* More than one latch edge. */ + return NULL; + + latch = cand; + } + + return latch; +} + /* Find all the natural loops in the function and save in LOOPS structure and recalculate loop_father information in basic block structures. If LOOPS is non-NULL then the loop structures for already recorded loops @@ -482,29 +509,10 @@ flow_loops_find (struct loops *loops) { struct loop *loop = larray[i]; basic_block header = loop->header; - edge_iterator ei; - edge e; flow_loop_tree_node_add (header->loop_father, loop); loop->num_nodes = flow_loop_nodes_find (loop->header, loop); - - /* Look for the latch for this header block, if it has just a - single one. */ - FOR_EACH_EDGE (e, ei, header->preds) - { - basic_block latch = e->src; - - if (flow_bb_inside_loop_p (loop, latch)) - { - if (loop->latch != NULL) - { - /* More than one latch edge. */ - loop->latch = NULL; - break; - } - loop->latch = latch; - } - } + loop->latch = find_single_latch (loop); } return loops; @@ -1434,6 +1442,28 @@ verify_loop_structure (void) error ("loop %d%'s latch is not dominated by its header", i); err = 1; } + if (find_single_latch (loop) == NULL) + { + error ("loop %d%'s latch is is not the only latch", i); + err = 1; + } + } + else + { + if (loops_state_satisfies_p (LOOPS_MAY_HAVE_MULTIPLE_LATCHES)) + { + if (find_single_latch (loop) != NULL) + { + error ("loop %d%'s latch is missing", i); + err = 1; + } + } + else + { + error ("loop %d%'s latch is missing, and loops may not have" + " multiple latches", i); + err = 1; + } } if (loops_state_satisfies_p (LOOPS_HAVE_SIMPLE_LATCHES)) { diff --git a/gcc/cfgloop.h b/gcc/cfgloop.h index ee73bf9..7faf591 100644 --- a/gcc/cfgloop.h +++ b/gcc/cfgloop.h @@ -270,6 +270,7 @@ bool mark_irreducible_loops (void); void release_recorded_exits (function *); void record_loop_exits (void); void rescan_loop_exit (edge, bool, bool); +basic_block find_single_latch (struct loop*); /* Loop data structure manipulation/querying. */ extern void flow_loop_tree_node_add (struct loop *, struct loop *); diff --git a/gcc/omp-low.c b/gcc/omp-low.c index 0d4c6e5..2d782eb 100644 --- a/gcc/omp-low.c +++ b/gcc/omp-low.c @@ -8903,6 +8903,7 @@ expand_omp_for_generic (struct omp_region *region, orig_loop->header = l1_bb; /* The loop may have multiple latches. */ add_loop (orig_loop, new_loop); + orig_loop->latch = find_single_latch (orig_loop); } } } |