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 D06C43858D33; Tue, 14 Feb 2023 15:59:39 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D06C43858D33
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1676390379;
	bh=+tQnnaAt4CWETbZvko1XymCV6v2XVbnS1y19Jjv/o1Q=;
	h=From:To:Subject:Date:From;
	b=nqSA6gpL6VWxYa2xM9nxXF9uGa4GTmpzjJDajrjdqzyecFpiR+6TX5eqZPMqMomh6
	 TW6nvHh4znbp77dxaODrJwDbnEjfPsnmLgSX9VTibmgc53oIKBJJYc/nSGjFd4fYrv
	 nauns2XZrI5o69iM/dUjOO19yhYHQWGf37DQ3sYE=
From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/108787] New: [13 Regression] libsodium miscompilation on
 power9 starting with r13-2107
Date: Tue, 14 Feb 2023 15:59:39 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: target
X-Bugzilla-Version: 13.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: jakub at gcc dot gnu.org
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: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status
 bug_severity priority component assigned_to reporter target_milestone
Message-ID: <bug-108787-4@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=3D108787

            Bug ID: 108787
           Summary: [13 Regression] libsodium miscompilation on power9
                    starting with r13-2107
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jakub at gcc dot gnu.org
  Target Milestone: ---

The following testcase is miscompiled with -mcpu=3Dpower9 -mtune=3Dpower9 s=
tarting
with
r13-2107-gdefa08a33672d200edbdd7f87ed7afa442249261 .  Doesn't reproduce wit=
hout
-fPIC though.

/* { dg-do run { target int128 } } */
/* { dg-options "-O2" } */
/* { dg-additional-options "-fPIC" { target fpic } } */

typedef unsigned __int128 uint128_t;

static inline unsigned long long
foo (const unsigned char src[8])
{
  unsigned long long w;
  __builtin_memcpy (&w, src, sizeof w);
  return w;
}

typedef struct S {
  unsigned long long r[3], h[3];
  unsigned char final;
} S;

__attribute__((noipa)) static void
poly1305_blocks (S *st, const unsigned char *m,
                 unsigned long long bytes)
{
  const unsigned long long hibit =3D st->final ? 0ULL : (1ULL << 40);
  unsigned long long r0, r1, r2;
  unsigned long long s1, s2;
  unsigned long long h0, h1, h2;
  unsigned long long c;
  uint128_t d0, d1, d2, d;

  r0 =3D st->r[0];
  r1 =3D st->r[1];
  r2 =3D st->r[2];
  h0 =3D st->h[0];
  h1 =3D st->h[1];
  h2 =3D st->h[2];
  s1 =3D r1 * (5 << 2);
  s2 =3D r2 * (5 << 2);
  while (bytes >=3D 16)
    {
      unsigned long long t0, t1;

      t0 =3D foo (&m[0]);
      t1 =3D foo (&m[8]);
      h0 +=3D t0 & 0xfffffffffff;
      h1 +=3D ((t0 >> 44) | (t1 << 20)) & 0xfffffffffff;
      h2 +=3D (((t1 >> 24)) & 0x3ffffffffff) | hibit;
      d0 =3D ((uint128_t) h0 * r0);
      d =3D ((uint128_t) h1 * s2);
      d0 +=3D d;
      d =3D ((uint128_t) h2 * s1);
      d0 +=3D d;
      d1 =3D ((uint128_t) h0 * r1);
      d =3D ((uint128_t) h1 * r0);
      d1 +=3D d;
      d =3D ((uint128_t) h2 * s2);
      d1 +=3D d;
      d2 =3D ((uint128_t) h0 * r2);
      d =3D ((uint128_t) h1 * r1);
      d2 +=3D d;
      d =3D ((uint128_t) h2 * r0);
      d2 +=3D d;
      c =3D (unsigned long long) (d0 >> (44));
      h0 =3D (unsigned long long) (d0) & 0xfffffffffff;
      d1 +=3D c;
      c =3D (unsigned long long) (d1 >> (44));
      h1 =3D (unsigned long long) (d1) & 0xfffffffffff;
      d2 +=3D c;
      c =3D (unsigned long long) (d2 >> (42));
      h2 =3D (unsigned long long) (d2) & 0x3ffffffffff;
      h0 +=3D c * 5;
      c =3D (h0 >> 44);
      h0 =3D h0 & 0xfffffffffff;
      h1 +=3D c;
      m +=3D 16;
      bytes -=3D 16;
    }
  st->h[0] =3D h0;
  st->h[1] =3D h1;
  st->h[2] =3D h2;
}

int
main ()
{
  if (sizeof (unsigned long long) !=3D 8 || sizeof (uint128_t) !=3D 16)
    return 0;
  S st =3D { .r =3D { 0x42c052bac7bULL, 0x7ab6080f47bULL, 0x455e9a405ULL },
           .h =3D { 0x3efe88da491ULL, 0xd10577b4a44ULL, 0x3efa677b3dbULL } =
};
  unsigned long long l[2] =3D { 0, 0x72ULL };
  poly1305_blocks (&st, (unsigned char *) &l[0], sizeof (l));
  if (st.h[0] !=3D 0xef4cd4260ULL || st.h[1] !=3D 0x5d0e836abb6ULL || st.h[=
2] !=3D
0x171e724427ULL)
    __builtin_abort ();
  return 0;
}=