From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id 0E34F385843F; Mon, 8 Nov 2021 15:19:48 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 0E34F385843F MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Richard Biener To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-5001] Fix spurious valgrind errors in irred loop verification X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/master X-Git-Oldrev: 18546941ae4c56cd9240d2dc2ca2806e01eb6fb7 X-Git-Newrev: d626fe77cdc40de0ae1651c8b94090eea73a719f Message-Id: <20211108151948.0E34F385843F@sourceware.org> Date: Mon, 8 Nov 2021 15:19:48 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 08 Nov 2021 15:19:48 -0000 https://gcc.gnu.org/g:d626fe77cdc40de0ae1651c8b94090eea73a719f commit r12-5001-gd626fe77cdc40de0ae1651c8b94090eea73a719f Author: Richard Biener Date: Mon Nov 8 15:21:08 2021 +0100 Fix spurious valgrind errors in irred loop verification The sbitmap bitmap_{set,clear}_bit changes trigger spurious uninit value use reportings from valgrind since we now read the old value before setting/clearing a bit so verify_loop_structures optimization to not clear the sbitmap is reported. Fixed by using a temporary BB flag which should also be more efficient in terms of cache re-use. 2021-11-08 Richard Biener * cfgloop.c (verify_loop_structure): Use a temporary BB flag instead of an sbitmap to cache irreducible state. Diff: --- gcc/cfgloop.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) diff --git a/gcc/cfgloop.c b/gcc/cfgloop.c index 2ba9918bfa2..20c24c13c36 100644 --- a/gcc/cfgloop.c +++ b/gcc/cfgloop.c @@ -1567,19 +1567,17 @@ verify_loop_structure (void) /* Check irreducible loops. */ if (loops_state_satisfies_p (LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS)) { - auto_edge_flag saved_irr_mask (cfun); - /* Record old info. */ - auto_sbitmap irreds (last_basic_block_for_fn (cfun)); + auto_edge_flag saved_edge_irr (cfun); + auto_bb_flag saved_bb_irr (cfun); + /* Save old info. */ FOR_EACH_BB_FN (bb, cfun) { edge_iterator ei; if (bb->flags & BB_IRREDUCIBLE_LOOP) - bitmap_set_bit (irreds, bb->index); - else - bitmap_clear_bit (irreds, bb->index); + bb->flags |= saved_bb_irr; FOR_EACH_EDGE (e, ei, bb->succs) if (e->flags & EDGE_IRREDUCIBLE_LOOP) - e->flags |= saved_irr_mask; + e->flags |= saved_edge_irr; } /* Recount it. */ @@ -1591,34 +1589,35 @@ verify_loop_structure (void) edge_iterator ei; if ((bb->flags & BB_IRREDUCIBLE_LOOP) - && !bitmap_bit_p (irreds, bb->index)) + && !(bb->flags & saved_bb_irr)) { error ("basic block %d should be marked irreducible", bb->index); err = 1; } else if (!(bb->flags & BB_IRREDUCIBLE_LOOP) - && bitmap_bit_p (irreds, bb->index)) + && (bb->flags & saved_bb_irr)) { error ("basic block %d should not be marked irreducible", bb->index); err = 1; } + bb->flags &= ~saved_bb_irr; FOR_EACH_EDGE (e, ei, bb->succs) { if ((e->flags & EDGE_IRREDUCIBLE_LOOP) - && !(e->flags & saved_irr_mask)) + && !(e->flags & saved_edge_irr)) { error ("edge from %d to %d should be marked irreducible", e->src->index, e->dest->index); err = 1; } else if (!(e->flags & EDGE_IRREDUCIBLE_LOOP) - && (e->flags & saved_irr_mask)) + && (e->flags & saved_edge_irr)) { error ("edge from %d to %d should not be marked irreducible", e->src->index, e->dest->index); err = 1; } - e->flags &= ~saved_irr_mask; + e->flags &= ~saved_edge_irr; } } }