Re: [PATCH v1] x86: Add missing IS_IN (libc) check to memmove-ssse3.S

["H.J. Lu" <hjl.tools@gmail.com>]

On Wed, Jun 29, 2022 at 6:56 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
>
> Was missing to for the multiarch build rtld-memmove-ssse3.os was
> being built and exporting symbols:
>
> >$ nm string/rtld-memmove-ssse3.os
>                  U __GI___chk_fail
> 0000000000000020 T __memcpy_chk_ssse3
> 0000000000000040 T __memcpy_ssse3
> 0000000000000020 T __memmove_chk_ssse3
> 0000000000000040 T __memmove_ssse3
> 0000000000000000 T __mempcpy_chk_ssse3
> 0000000000000010 T __mempcpy_ssse3
>                  U __x86_shared_cache_size_half
>
> Introduced after 2.35 in:
>
> commit 26b2478322db94edc9e0e8f577b2f71d291e5acb
> Author: Noah Goldstein <goldstein.w.n@gmail.com>
> Date:   Thu Apr 14 11:47:40 2022 -0500
>
>     x86: Reduce code size of mem{move|pcpy|cpy}-ssse3
> ---
>  sysdeps/x86_64/multiarch/memmove-ssse3.S | 60 +++++++++++++++++-------
>  1 file changed, 44 insertions(+), 16 deletions(-)
>
> diff --git a/sysdeps/x86_64/multiarch/memmove-ssse3.S b/sysdeps/x86_64/multiarch/memmove-ssse3.S
> index 310ff62b86..a88fde4a8f 100644
> --- a/sysdeps/x86_64/multiarch/memmove-ssse3.S
> +++ b/sysdeps/x86_64/multiarch/memmove-ssse3.S
> @@ -1,19 +1,42 @@
> -#include <sysdep.h>
> -
> -#ifndef MEMMOVE
> -# define MEMMOVE       __memmove_ssse3
> -# define MEMMOVE_CHK   __memmove_chk_ssse3
> -# define MEMCPY        __memcpy_ssse3
> -# define MEMCPY_CHK    __memcpy_chk_ssse3
> -# define MEMPCPY       __mempcpy_ssse3
> -# define MEMPCPY_CHK   __mempcpy_chk_ssse3
> -#endif
> +/* memmove/memcpy/mempcpy optimized for aligned access with SSSE3.
> +   All versions must be listed in ifunc-impl-list.c.
> +   Copyright (C) 2022 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library 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
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +
> +#if IS_IN (libc)
> +
> +# include <sysdep.h>
> +# ifndef MEMMOVE
> +#  define MEMMOVE      __memmove_ssse3
> +#  define MEMMOVE_CHK  __memmove_chk_ssse3
> +#  define MEMCPY       __memcpy_ssse3
> +#  define MEMCPY_CHK   __memcpy_chk_ssse3
> +#  define MEMPCPY      __mempcpy_ssse3
> +#  define MEMPCPY_CHK  __mempcpy_chk_ssse3
> +# endif
>
>         .section .text.ssse3, "ax", @progbits
> +# if defined SHARED
>  ENTRY(MEMPCPY_CHK)
>         cmp     %RDX_LP, %RCX_LP
>         jb      HIDDEN_JUMPTARGET(__chk_fail)
>  END(MEMPCPY_CHK)
> +# endif
>
>  ENTRY(MEMPCPY)
>         mov     %RDI_LP, %RAX_LP
> @@ -21,10 +44,12 @@ ENTRY(MEMPCPY)
>         jmp     L(start)
>  END(MEMPCPY)
>
> +# if defined SHARED
>  ENTRY(MEMMOVE_CHK)
>         cmp     %RDX_LP, %RCX_LP
>         jb      HIDDEN_JUMPTARGET(__chk_fail)
>  END(MEMMOVE_CHK)
> +# endif
>
>  ENTRY_P2ALIGN(MEMMOVE, 6)
>  # ifdef __ILP32__
> @@ -124,11 +149,11 @@ L(more_2x_vec):
>            loop.  */
>         movups  %xmm0, (%rdi)
>
> -#ifdef SHARED_CACHE_SIZE_HALF
> +# ifdef SHARED_CACHE_SIZE_HALF
>         cmp     $SHARED_CACHE_SIZE_HALF, %RDX_LP
> -#else
> +# else
>         cmp     __x86_shared_cache_size_half(%rip), %rdx
> -#endif
> +# endif
>         ja      L(large_memcpy)
>
>         leaq    -64(%rdi, %rdx), %r8
> @@ -206,7 +231,7 @@ L(end_loop_fwd):
>
>         /* Extactly 64 bytes if `jmp L(end_loop_fwd)` is long encoding.
>            60 bytes otherwise.  */
> -#define ALIGNED_LOOP_FWD(align_by);    \
> +# define ALIGNED_LOOP_FWD(align_by);   \
>         .p2align 6;     \
>  L(loop_fwd_ ## align_by):      \
>         movaps  16(%rsi), %xmm0;        \
> @@ -275,7 +300,7 @@ L(end_large_loop_fwd):
>
>         /* Size > 64 bytes and <= 96 bytes. 32-byte align between ensure
>            96-byte spacing between each.  */
> -#define ALIGNED_LARGE_LOOP_FWD(align_by);      \
> +# define ALIGNED_LARGE_LOOP_FWD(align_by);     \
>         .p2align 5;     \
>  L(large_loop_fwd_ ## align_by):        \
>         movaps  16(%rsi), %xmm0;        \
> @@ -343,7 +368,7 @@ L(end_loop_bkwd):
>
>         /* Extactly 64 bytes if `jmp L(end_loop_bkwd)` is long encoding.
>            60 bytes otherwise.  */
> -#define ALIGNED_LOOP_BKWD(align_by);   \
> +# define ALIGNED_LOOP_BKWD(align_by);  \
>         .p2align 6;     \
>  L(loop_bkwd_ ## align_by):     \
>         movaps  32(%rsi), %xmm1;        \
> @@ -381,4 +406,7 @@ L(loop_bkwd_ ## align_by):  \
>  END(MEMMOVE)
>
>  strong_alias (MEMMOVE, MEMCPY)
> +# if defined SHARED
>  strong_alias (MEMMOVE_CHK, MEMCPY_CHK)
> +# endif
> +#endif
> --
> 2.34.1
>

LGTM.

Thanks.

-- 
H.J.