From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id 015843858D28; Mon, 19 Jun 2023 11:02:39 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 015843858D28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1687172559; bh=05iazm6Ob8QkyZX3gSeuRxlgOyjfOtfV7kkRX07tlhQ=; h=From:To:Subject:Date:From; b=swqlLILIsOXKNDfKSjjLFN917vWpYxrIgpYIN/K+DGMCixY5VdSNPti5sKBrmpNPU 6AzlMvJLUz5ykylDVSJ8fDfV55fNO3XJ8lVl4sLbegt+jNE8g+qYFodU/sRrWC2DcK O4WWgXo268zsCYmTiVKsFlcYno3kxM1NJtNdzpoQ= 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 r14-1939] tree-optimization/110298 - CFG cleanup and stale nb_iterations X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/master X-Git-Oldrev: de2d3b69eefde005759279d6739d9a0dbd2a05cc X-Git-Newrev: 916add3bf6e46467e4391e358b11ecfbc4daa275 Message-Id: <20230619110239.015843858D28@sourceware.org> Date: Mon, 19 Jun 2023 11:02:39 +0000 (GMT) List-Id: https://gcc.gnu.org/g:916add3bf6e46467e4391e358b11ecfbc4daa275 commit r14-1939-g916add3bf6e46467e4391e358b11ecfbc4daa275 Author: Richard Biener Date: Mon Jun 19 09:52:45 2023 +0200 tree-optimization/110298 - CFG cleanup and stale nb_iterations When unrolling we eventually kill nb_iterations info since it may refer to removed SSA names. But we do this only after cleaning up the CFG which in turn can end up accessing it. Fixed by swapping the two. PR tree-optimization/110298 * tree-ssa-loop-ivcanon.cc (tree_unroll_loops_completely): Clear number of iterations info before cleaning up the CFG. * gcc.dg/torture/pr110298.c: New testcase. Diff: --- gcc/testsuite/gcc.dg/torture/pr110298.c | 20 ++++++++++++++++++++ gcc/tree-ssa-loop-ivcanon.cc | 7 ++++--- 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/gcc/testsuite/gcc.dg/torture/pr110298.c b/gcc/testsuite/gcc.dg/torture/pr110298.c new file mode 100644 index 00000000000..139f5c77d89 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr110298.c @@ -0,0 +1,20 @@ +/* { dg-do compile } */ + +int a, b, c, d, e; +int f() { + c = 0; + for (; c >= 0; c--) { + d = 0; + for (; d <= 0; d++) { + e = 0; + for (; d + c + e >= 0; e--) + ; + a = 1; + b = 0; + for (; a; ++b) + a *= 2; + for (; b + d >= 0;) + return 0; + } + } +} diff --git a/gcc/tree-ssa-loop-ivcanon.cc b/gcc/tree-ssa-loop-ivcanon.cc index 6a962a9f503..491b57ec0f1 100644 --- a/gcc/tree-ssa-loop-ivcanon.cc +++ b/gcc/tree-ssa-loop-ivcanon.cc @@ -1520,15 +1520,16 @@ tree_unroll_loops_completely (bool may_increase_size, bool unroll_outer) } BITMAP_FREE (fathers); + /* Clean up the information about numbers of iterations, since + complete unrolling might have invalidated it. */ + scev_reset (); + /* This will take care of removing completely unrolled loops from the loop structures so we can continue unrolling now innermost loops. */ if (cleanup_tree_cfg ()) update_ssa (TODO_update_ssa_only_virtuals); - /* Clean up the information about numbers of iterations, since - complete unrolling might have invalidated it. */ - scev_reset (); if (flag_checking && loops_state_satisfies_p (LOOP_CLOSED_SSA)) verify_loop_closed_ssa (true); }