From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 755533858D33; Tue, 14 Feb 2023 21:09:01 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 755533858D33
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1676408941;
	bh=miri4qNBHpQurvgV0fuXHwn5Ead9Thl4jMp1YIkuxuU=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=WAp5d/PN/Y4LAM4NfDyyrjpOiKLxc9vKSD7HCAGKomH+hryv3OADdv9Bx2UnrLgd0
	 xz6d0Fa2NsrepRUskIAnsoBXj3ZIzI9MycIJ4KQ9mCQNoO90gZFGNb4nu/YHTmSbyF
	 UxqaztYOG/MIChrtFAjTlPajnP9258efLasBokhA=
From: "dcb314 at hotmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/108657] [13 Regression] csmith: possible wrong
 checksum with -O3 and -ftrivial-auto-var-init=zero
Date: Tue, 14 Feb 2023 21:09:01 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: middle-end
X-Bugzilla-Version: 13.0
X-Bugzilla-Keywords: needs-reduction, wrong-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: dcb314 at hotmail dot com
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 13.0
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-108657-4-yKI8ujB7SO@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-108657-4@http.gcc.gnu.org/bugzilla/>
References: <bug-108657-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108657

--- Comment #14 from David Binderman <dcb314 at hotmail dot com> ---
After five hours of reduction, cvise has:

crc32_tab[256];
unsigned crc32_context =3D 4294967295;
void crc32_byte(b) {
  crc32_context =3D crc32_context >> 8 ^ crc32_tab[(crc32_context ^ b) & 25=
5];
}
void transparent_crc(long val, char *vname) {
  crc32_context =3D crc32_context >> 8 ^ crc32_tab[(crc32_context ^ val) & =
255];
  crc32_byte(val >> 8);
  crc32_byte(val >> 16);
  crc32_byte(val >> 24);
  crc32_byte(val >> 32);
  crc32_byte(val >> 40);
  crc32_byte(val >> 48);
  crc32_byte(val >> 56);
  printf("...checksum after hashing %s : %lX\n", vname,
         crc32_context ^ 4294967295);
}
g_21 =3D -8;
short g_41;
g_78;
static *g_451 =3D &g_78;
g_452;
func_11___trans_tmp_13;
main_i;
unsigned main_crc;
main_j;
void main() {
  for (; main_i < 256; main_i++) {
    main_crc =3D main_i;
    main_j =3D 8;
    for (; main_j; main_j--)
      if (main_crc & 1)
        main_crc =3D main_crc >> 1 ^ 3988292384;
      else
        main_crc >>=3D 1;
    crc32_tab[main_i] =3D main_crc;
  }
  int l_794;
  g_41 =3D 53935 & g_21;
  g_21 =3D -18;
  g_78 =3D 1;
  for (; g_78 >=3D 0; g_78 -=3D 1) {
    g_452 =3D l_794 =3D 0;
    for (; l_794 <=3D 3; l_794 +=3D 1) {
      short l_895[1];
      if (g_452)
        break;
      g_452 ^=3D func_11___trans_tmp_13;
    }
  }
  *g_451 =3D 8 || 0;
  transparent_crc(g_21, "");
  transparent_crc(g_41, "");
  transparent_crc(2185655400, "");
  transparent_crc(g_78, "g_78");
}=