Do not allow irreducible loops/regions in a scop

Irreducible regions are not going to be optimized by ISL
so discard them early. Passes bootstrap and regtest.

gcc/ChangeLog:

2015-11-06  Aditya Kumar  <aditya.k7@samsung.com>

        * graphite-scop-detection.c (scop_detection::merge_sese): Entry and exit edges should not be a part of irreducible loop.
        (scop_detection::can_represent_loop_1): Loops should not be irreducible.
        (scop_detection::harmful_stmt_in_region): All the basic block should belong to reducible loops.

Co-Authored-By: Sebastian Pop <s.pop@samsung.com>

From-SVN: r229888
This commit is contained in:
Aditya Kumar 2015-11-06 20:43:40 +00:00 committed by Sebastian Pop
parent 246cc06002
commit 1167ebe707
2 changed files with 19 additions and 2 deletions

View File

@ -1,3 +1,13 @@
2015-11-06 Aditya Kumar <aditya.k7@samsung.com>
Sebastian Pop <s.pop@samsung.com>
* graphite-scop-detection.c (scop_detection::merge_sese): Entry
and exit edges should not be a part of irreducible loop.
(scop_detection::can_represent_loop_1): Loops should not be
irreducible.
(scop_detection::harmful_stmt_in_region): All the basic block
should belong to reducible loops.
2015-11-06 Christophe Lyon <christophe.lyon@linaro.org>
* config/aarch64/aarch64-simd-builtins.def: Update builtins

View File

@ -794,7 +794,8 @@ scop_detection::merge_sese (sese_l first, sese_l second) const
get_entry_bb (second));
edge entry = get_nearest_dom_with_single_entry (dom);
if (!entry)
if (!entry || (entry->flags & EDGE_IRREDUCIBLE_LOOP))
return invalid_sese;
basic_block pdom = nearest_common_dominator (CDI_POST_DOMINATORS,
@ -803,7 +804,8 @@ scop_detection::merge_sese (sese_l first, sese_l second) const
pdom = nearest_common_dominator (CDI_POST_DOMINATORS, dom, pdom);
edge exit = get_nearest_pdom_with_single_exit (pdom);
if (!exit)
if (!exit || (exit->flags & EDGE_IRREDUCIBLE_LOOP))
return invalid_sese;
sese_l combined (entry, exit);
@ -923,6 +925,7 @@ scop_detection::can_represent_loop_1 (loop_p loop, sese_l scop)
struct tree_niter_desc niter_desc;
return single_exit (loop)
&& !(loop_preheader_edge (loop)->flags & EDGE_IRREDUCIBLE_LOOP)
&& number_of_iterations_exit (loop, single_exit (loop), &niter_desc, false)
&& niter_desc.control.no_overflow
&& (niter = number_of_latch_executions (loop))
@ -1053,6 +1056,10 @@ scop_detection::harmful_stmt_in_region (sese_l scop) const
if (!dominated_by_p (CDI_POST_DOMINATORS, bb, exit_bb))
continue;
/* The basic block should not be part of an irreducible loop. */
if (bb->flags & BB_IRREDUCIBLE_LOOP)
return true;
if (harmful_stmt_in_bb (scop, bb))
return true;
}