From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id 274293858D35; Mon, 6 May 2024 13:15:07 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 274293858D35 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1715001307; bh=uxd52cwO1tO3VSJHVaNirEHPyqi+0c0p3pPbsFucycg=; h=From:To:Subject:Date:From; b=EeL1/XjhdjLpbp9kS3ezKv+VWXyQJ8LIPiMo/0aRav1vpWhlb5Z0dPBiMBn00Eyvx UFvTaxxxzyu85oP6dqp64pS8lBQO8LTdbK1yLG797p0MaHAq/KlfLrpOC48RSqhpvk Z4F0NuH2BVuIIE6g92krav7f6p/fBgDHVdsew+MA= 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 r13-8693] tree-optimization/113630 - invalid code hoisting X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/releases/gcc-13 X-Git-Oldrev: 429935510202c4efee933bf907fd9dff816193f2 X-Git-Newrev: 47cd06042237bf2d4f05b8355362bc038f6fa445 Message-Id: <20240506131507.274293858D35@sourceware.org> Date: Mon, 6 May 2024 13:15:07 +0000 (GMT) List-Id: https://gcc.gnu.org/g:47cd06042237bf2d4f05b8355362bc038f6fa445 commit r13-8693-g47cd06042237bf2d4f05b8355362bc038f6fa445 Author: Richard Biener Date: Wed Jan 31 11:28:50 2024 +0100 tree-optimization/113630 - invalid code hoisting The following avoids code hoisting (but also PRE insertion) of expressions that got value-numbered to another one that are not a valid replacement (but still compute the same value). This time because the access path ends in a structure with different size, meaning we consider a related access as not trapping because of the size of the base of the access. PR tree-optimization/113630 * tree-ssa-pre.cc (compute_avail): Avoid registering a reference with a representation with not matching base access size. * gcc.dg/torture/pr113630.c: New testcase. (cherry picked from commit 724b64304ff5c8ac08a913509afd6fde38d7b767) Diff: --- gcc/testsuite/gcc.dg/torture/pr113630.c | 4 ++++ gcc/tree-ssa-pre.cc | 14 ++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/gcc/testsuite/gcc.dg/torture/pr113630.c b/gcc/testsuite/gcc.dg/torture/pr113630.c new file mode 100644 index 00000000000..72ebdefae27 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr113630.c @@ -0,0 +1,4 @@ +/* { dg-do run { target { { *-*-linux* *-*-gnu* *-*-uclinux* } && mmap } } } */ +/* { dg-additional-options "-fno-strict-aliasing" } */ + +#include "pr110799.c" diff --git a/gcc/tree-ssa-pre.cc b/gcc/tree-ssa-pre.cc index dfcc9ec4711..9e9a2f9d26a 100644 --- a/gcc/tree-ssa-pre.cc +++ b/gcc/tree-ssa-pre.cc @@ -4224,6 +4224,20 @@ compute_avail (function *fun) = wide_int_to_tree (ptr_type_node, wi::to_wide (ref1->op2)); } + /* We also need to make sure that the access path + ends in an access of the same size as otherwise + we might assume an access may not trap while in + fact it might. That's independent of whether + TBAA is in effect. */ + if (TYPE_SIZE (ref1->type) != TYPE_SIZE (ref2->type) + && (! TYPE_SIZE (ref1->type) + || ! TYPE_SIZE (ref2->type) + || ! operand_equal_p (TYPE_SIZE (ref1->type), + TYPE_SIZE (ref2->type)))) + { + operands.release (); + continue; + } operands.release (); result = get_or_alloc_expr_for_reference