Re: [PATCH] s390: libatomic: Fix 16 byte atomic {cas,load,store}

[Andreas Krebbel <krebbel@linux.ibm.com>]

On 3/2/23 16:24, Stefan Schulze Frielinghaus wrote:
> This is a follow-up to commit a4c6bd0821099f6b8c0f64a96ffd9d01a025c413
> introducing a runtime check for alignment for 16 byte atomic
> compare-exchange, load, and store.
> 
> Bootstrapped and regtested on s390.
> Ok for mainline and gcc-{12,11,10}?
> 
> libatomic/ChangeLog:
> 
> 	* config/s390/cas_n.c: New file.
> 	* config/s390/load_n.c: New file.
> 	* config/s390/store_n.c: New file.

Ok. Thanks!

Andreas

> ---
>  libatomic/config/s390/cas_n.c   | 65 +++++++++++++++++++++++++++++++++
>  libatomic/config/s390/load_n.c  | 57 +++++++++++++++++++++++++++++
>  libatomic/config/s390/store_n.c | 54 +++++++++++++++++++++++++++
>  3 files changed, 176 insertions(+)
>  create mode 100644 libatomic/config/s390/cas_n.c
>  create mode 100644 libatomic/config/s390/load_n.c
>  create mode 100644 libatomic/config/s390/store_n.c
> 
> diff --git a/libatomic/config/s390/cas_n.c b/libatomic/config/s390/cas_n.c
> new file mode 100644
> index 00000000000..44b7152ca5d
> --- /dev/null
> +++ b/libatomic/config/s390/cas_n.c
> @@ -0,0 +1,65 @@
> +/* Copyright (C) 2018-2023 Free Software Foundation, Inc.
> +
> +   This file is part of the GNU Atomic Library (libatomic).
> +
> +   Libatomic is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published by
> +   the Free Software Foundation; either version 3 of the License, or
> +   (at your option) any later version.
> +
> +   Libatomic is distributed in the hope that it will be useful, but WITHOUT ANY
> +   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
> +   FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> +   more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include <libatomic_i.h>
> +
> +
> +/* Analog to config/s390/exch_n.c.  */
> +
> +#if !DONE && N == 16
> +bool
> +SIZE(libat_compare_exchange) (UTYPE *mptr, UTYPE *eptr, UTYPE newval,
> +			      int smodel, int fmodel UNUSED)
> +{
> +  if (!((uintptr_t)mptr & 0xf))
> +    {
> +      return __atomic_compare_exchange_n (
> +	(UTYPE *)__builtin_assume_aligned (mptr, 16), eptr, newval, false,
> +	__ATOMIC_SEQ_CST, __ATOMIC_RELAXED);
> +    }
> +  else
> +    {
> +      UTYPE oldval;
> +      UWORD magic;
> +      bool ret;
> +
> +      pre_seq_barrier (smodel);
> +      magic = protect_start (mptr);
> +
> +      oldval = *mptr;
> +      ret = (oldval == *eptr);
> +      if (ret)
> +	*mptr = newval;
> +      else
> +	*eptr = oldval;
> +
> +      protect_end (mptr, magic);
> +      post_seq_barrier (smodel);
> +
> +      return ret;
> +    }
> +}
> +#define DONE 1
> +#endif /* N == 16 */
> +
> +#include "../../cas_n.c"
> diff --git a/libatomic/config/s390/load_n.c b/libatomic/config/s390/load_n.c
> new file mode 100644
> index 00000000000..335d2f8b2c3
> --- /dev/null
> +++ b/libatomic/config/s390/load_n.c
> @@ -0,0 +1,57 @@
> +/* Copyright (C) 2018-2023 Free Software Foundation, Inc.
> +
> +   This file is part of the GNU Atomic Library (libatomic).
> +
> +   Libatomic is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published by
> +   the Free Software Foundation; either version 3 of the License, or
> +   (at your option) any later version.
> +
> +   Libatomic is distributed in the hope that it will be useful, but WITHOUT ANY
> +   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
> +   FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> +   more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include <libatomic_i.h>
> +
> +
> +/* Analog to config/s390/exch_n.c.  */
> +
> +#if !DONE && N == 16
> +UTYPE
> +SIZE(libat_load) (UTYPE *mptr, int smodel)
> +{
> +  if (!((uintptr_t)mptr & 0xf))
> +    {
> +      return __atomic_load_n ((UTYPE *)__builtin_assume_aligned (mptr, 16),
> +			      __ATOMIC_SEQ_CST);
> +    }
> +  else
> +    {
> +      UTYPE ret;
> +      UWORD magic;
> +
> +      pre_seq_barrier (smodel);
> +      magic = protect_start (mptr);
> +
> +      ret = *mptr;
> +
> +      protect_end (mptr, magic);
> +      post_seq_barrier (smodel);
> +
> +      return ret;
> +    }
> +}
> +#define DONE 1
> +#endif /* N == 16 */
> +
> +#include "../../load_n.c"
> diff --git a/libatomic/config/s390/store_n.c b/libatomic/config/s390/store_n.c
> new file mode 100644
> index 00000000000..9e5b2b8213d
> --- /dev/null
> +++ b/libatomic/config/s390/store_n.c
> @@ -0,0 +1,54 @@
> +/* Copyright (C) 2018-2023 Free Software Foundation, Inc.
> +
> +   This file is part of the GNU Atomic Library (libatomic).
> +
> +   Libatomic is free software; you can redistribute it and/or modify it
> +   under the terms of the GNU General Public License as published by
> +   the Free Software Foundation; either version 3 of the License, or
> +   (at your option) any later version.
> +
> +   Libatomic is distributed in the hope that it will be useful, but WITHOUT ANY
> +   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
> +   FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> +   more details.
> +
> +   Under Section 7 of GPL version 3, you are granted additional
> +   permissions described in the GCC Runtime Library Exception, version
> +   3.1, as published by the Free Software Foundation.
> +
> +   You should have received a copy of the GNU General Public License and
> +   a copy of the GCC Runtime Library Exception along with this program;
> +   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#include <libatomic_i.h>
> +
> +
> +/* Analog to config/s390/exch_n.c.  */
> +
> +#if !DONE && N == 16
> +void
> +SIZE(libat_store) (UTYPE *mptr, UTYPE newval, int smodel)
> +{
> +  if (!((uintptr_t)mptr & 0xf))
> +    {
> +      __atomic_store_n ((UTYPE *)__builtin_assume_aligned (mptr, 16), newval,
> +			__ATOMIC_SEQ_CST);
> +    }
> +  else
> +    {
> +      UWORD magic;
> +
> +      pre_seq_barrier (smodel);
> +      magic = protect_start (mptr);
> +
> +      *mptr = newval;
> +
> +      protect_end (mptr, magic);
> +      post_seq_barrier (smodel);
> +    }
> +}
> +#define DONE 1
> +#endif /* N == 16 */
> +
> +#include "../../store_n.c"