From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id 50E403858D33; Mon, 13 Feb 2023 07:27:04 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 50E403858D33 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1676273224; bh=i2EXYF5QqgW4ztI89BNKanEYny3IDgvB9ZrNKUpshHA=; h=From:To:Subject:Date:From; b=PDP/fFYIvvfhk+j3MinS9wX9T+n/MLymWHuZGbgJH+IIaS7ji181cM0w6IBz29/eo 3aQnIpJCisd/KNWZvol5xnb8+yX2R1o7faZixryz8YoPEVPVG5NMpFWBmz2YK7lG0r t/P00DyyorTTce/j/X5z9R824aJXYbWGdz0Z1pN4= 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 r13-5958] tree-optimization/106722 - fix CD-DCE edge marking X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/master X-Git-Oldrev: 89367e794613bdeb21df3e6fc0215f0acd553ef8 X-Git-Newrev: 338739645b8e5bf34636d8d4829d7650001ad08c Message-Id: <20230213072704.50E403858D33@sourceware.org> Date: Mon, 13 Feb 2023 07:27:04 +0000 (GMT) List-Id: https://gcc.gnu.org/g:338739645b8e5bf34636d8d4829d7650001ad08c commit r13-5958-g338739645b8e5bf34636d8d4829d7650001ad08c Author: Richard Biener Date: Fri Feb 10 10:28:29 2023 +0100 tree-optimization/106722 - fix CD-DCE edge marking The following fixes a latent issue when we mark control edges but end up with marking a block with no stmts necessary. In this case we fail to mark dependent control edges of that block. PR tree-optimization/106722 * tree-ssa-dce.cc (mark_last_stmt_necessary): Return whether we marked a stmt. (mark_control_dependent_edges_necessary): When mark_last_stmt_necessary didn't mark any stmt make sure to mark its control dependent edges. (propagate_necessity): Likewise. * gcc.dg/torture/pr108737.c: New testcase. Diff: --- gcc/testsuite/gcc.dg/torture/pr108737.c | 19 +++++++++++++++++++ gcc/tree-ssa-dce.cc | 20 +++++++++++++------- 2 files changed, 32 insertions(+), 7 deletions(-) diff --git a/gcc/testsuite/gcc.dg/torture/pr108737.c b/gcc/testsuite/gcc.dg/torture/pr108737.c new file mode 100644 index 00000000000..c8388bcabeb --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr108737.c @@ -0,0 +1,19 @@ +/* { dg-do run } */ + +extern void exit (int); +extern void abort (void); + +void __attribute__((noipa)) foo () { exit (0); } + +void __attribute__((noipa)) blah (int x) +{ + while (1) { + if(x) foo(); + } +} + +int main() +{ + blah (1); + abort (); +} diff --git a/gcc/tree-ssa-dce.cc b/gcc/tree-ssa-dce.cc index 1f1ec2c8710..ceeb0ad5ab3 100644 --- a/gcc/tree-ssa-dce.cc +++ b/gcc/tree-ssa-dce.cc @@ -327,17 +327,23 @@ mark_stmt_if_obviously_necessary (gimple *stmt, bool aggressive) /* Mark the last statement of BB as necessary. */ -static void +static bool mark_last_stmt_necessary (basic_block bb) { gimple *stmt = last_stmt (bb); - bitmap_set_bit (last_stmt_necessary, bb->index); + if (!bitmap_set_bit (last_stmt_necessary, bb->index)) + return true; + bitmap_set_bit (bb_contains_live_stmts, bb->index); /* We actually mark the statement only if it is a control statement. */ if (stmt && is_ctrl_stmt (stmt)) - mark_stmt_necessary (stmt, true); + { + mark_stmt_necessary (stmt, true); + return true; + } + return false; } @@ -369,8 +375,8 @@ mark_control_dependent_edges_necessary (basic_block bb, bool ignore_self) continue; } - if (!bitmap_bit_p (last_stmt_necessary, cd_bb->index)) - mark_last_stmt_necessary (cd_bb); + if (!mark_last_stmt_necessary (cd_bb)) + mark_control_dependent_edges_necessary (cd_bb, false); } if (!skipped) @@ -790,8 +796,8 @@ propagate_necessity (bool aggressive) if (gimple_bb (stmt) != get_immediate_dominator (CDI_POST_DOMINATORS, arg_bb)) { - if (!bitmap_bit_p (last_stmt_necessary, arg_bb->index)) - mark_last_stmt_necessary (arg_bb); + if (!mark_last_stmt_necessary (arg_bb)) + mark_control_dependent_edges_necessary (arg_bb, false); } else if (arg_bb != ENTRY_BLOCK_PTR_FOR_FN (cfun) && !bitmap_bit_p (visited_control_parents,