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From: Szabolcs Nagy <Szabolcs.Nagy@arm.com>
To: Wilco Dijkstra <Wilco.Dijkstra@arm.com>,
	'GNU C Library' <libc-alpha@sourceware.org>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Subject: Re: [PATCH] AArch64: Cleanup ifuncs
Date: Wed, 1 Nov 2023 13:23:14 +0000	[thread overview]
Message-ID: <ZUJRQuZQYGj6iog/@arm.com> (raw)
In-Reply-To: <PAWPR08MB89824596BFE0B599400F787183DFA@PAWPR08MB8982.eurprd08.prod.outlook.com>

The 10/24/2023 13:33, Wilco Dijkstra wrote:
> Cleanup ifuncs.  Remove uses of libc_hidden_builtin_def, use ENTRY rather than
> ENTRY_ALIGN, remove unnecessary defines and conditional compilation.  Rename
> strlen_mte to strlen_generic.  Remove rtld-memset.
> 
> Passes regress, OK for commit?

OK.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>


> 
> ---
> 
> diff --git a/sysdeps/aarch64/memset.S b/sysdeps/aarch64/memset.S
> index 50e5da3e7aec3a7b4ef23676c35c34896e8078e6..bf3cf85c8a95fd8c03ae13c4173fe507040ee8cd 100644
> --- a/sysdeps/aarch64/memset.S
> +++ b/sysdeps/aarch64/memset.S
> @@ -29,7 +29,7 @@
>   *
>   */
> 
> -ENTRY_ALIGN (MEMSET, 6)
> +ENTRY (MEMSET)
> 
>         PTR_ARG (0)
>         SIZE_ARG (2)
> diff --git a/sysdeps/aarch64/multiarch/Makefile b/sysdeps/aarch64/multiarch/Makefile
> index e6099548b96b80b656f3f22cd8d5598634647360..a1a4de3cd93c48db6e47eebc9c111186efca53fb 100644
> --- a/sysdeps/aarch64/multiarch/Makefile
> +++ b/sysdeps/aarch64/multiarch/Makefile
> @@ -17,6 +17,6 @@ sysdep_routines += \
>    memset_kunpeng \
>    memset_mops \
>    strlen_asimd \
> -  strlen_mte \
> +  strlen_generic \
>  # sysdep_routines
>  endif
> diff --git a/sysdeps/aarch64/multiarch/ifunc-impl-list.c b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
> index da7f1153778efd41a15ef5aa900252f9e492b18d..836e8317a5d3b652134d199cf685499983b1a3fc 100644
> --- a/sysdeps/aarch64/multiarch/ifunc-impl-list.c
> +++ b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
> @@ -70,7 +70,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
> 
>    IFUNC_IMPL (i, name, strlen,
>               IFUNC_IMPL_ADD (array, i, strlen, !mte, __strlen_asimd)
> -             IFUNC_IMPL_ADD (array, i, strlen, 1, __strlen_mte))
> +             IFUNC_IMPL_ADD (array, i, strlen, 1, __strlen_generic))
> 
>    return 0;
>  }
> diff --git a/sysdeps/aarch64/multiarch/memchr_nosimd.S b/sysdeps/aarch64/multiarch/memchr_nosimd.S
> index 57e48375e91edd74ee0a69e747e09d995ae8fd4f..780075189902919345c5eb15cba7ea0929043d6a 100644
> --- a/sysdeps/aarch64/multiarch/memchr_nosimd.S
> +++ b/sysdeps/aarch64/multiarch/memchr_nosimd.S
> @@ -26,10 +26,6 @@
>   * Use base integer registers.
>   */
> 
> -#ifndef MEMCHR
> -# define MEMCHR __memchr_nosimd
> -#endif
> -
>  /* Arguments and results.  */
>  #define srcin          x0
>  #define chrin          x1
> @@ -62,7 +58,7 @@
>  #define REP8_7f                0x7f7f7f7f7f7f7f7f
> 
> 
> -ENTRY_ALIGN (MEMCHR, 6)
> +ENTRY (__memchr_nosimd)
> 
>         PTR_ARG (0)
>         SIZE_ARG (2)
> @@ -219,5 +215,4 @@ L(none_chr):
>         mov     result, 0
>         ret
> 
> -END (MEMCHR)
> -libc_hidden_builtin_def (MEMCHR)
> +END (__memchr_nosimd)
> diff --git a/sysdeps/aarch64/multiarch/memcpy_a64fx.S b/sysdeps/aarch64/multiarch/memcpy_a64fx.S
> index f89b5b670a16ceb944eb816d318e02628a239df8..baff7e96d0045dac5a6a7a8d555e997998c978dd 100644
> --- a/sysdeps/aarch64/multiarch/memcpy_a64fx.S
> +++ b/sysdeps/aarch64/multiarch/memcpy_a64fx.S
> @@ -39,9 +39,6 @@
>  #define vlen8  x8
> 
>  #if HAVE_AARCH64_SVE_ASM
> -# if IS_IN (libc)
> -#  define MEMCPY __memcpy_a64fx
> -#  define MEMMOVE __memmove_a64fx
> 
>         .arch armv8.2-a+sve
> 
> @@ -97,7 +94,7 @@
>  #undef BTI_C
>  #define BTI_C
> 
> -ENTRY (MEMCPY)
> +ENTRY (__memcpy_a64fx)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -234,11 +231,10 @@ L(last_bytes):
>         st1b    z3.b, p0, [dstend, -1, mul vl]
>         ret
> 
> -END (MEMCPY)
> -libc_hidden_builtin_def (MEMCPY)
> +END (__memcpy_a64fx)
> 
> 
> -ENTRY_ALIGN (MEMMOVE, 4)
> +ENTRY_ALIGN (__memmove_a64fx, 4)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -307,7 +303,5 @@ L(full_overlap):
>         mov     dst, dstin
>         b       L(last_bytes)
> 
> -END (MEMMOVE)
> -libc_hidden_builtin_def (MEMMOVE)
> -# endif /* IS_IN (libc) */
> +END (__memmove_a64fx)
>  #endif /* HAVE_AARCH64_SVE_ASM */
> diff --git a/sysdeps/aarch64/multiarch/memcpy_falkor.S b/sysdeps/aarch64/multiarch/memcpy_falkor.S
> index ec0e4ade24bbad76979d2e34a36eff7703d30264..67c4ab34eba40c37c6aae08be6cb5e11e2a82d17 100644
> --- a/sysdeps/aarch64/multiarch/memcpy_falkor.S
> +++ b/sysdeps/aarch64/multiarch/memcpy_falkor.S
> @@ -71,7 +71,7 @@
>     The non-temporal stores help optimize cache utilization.  */
> 
>  #if IS_IN (libc)
> -ENTRY_ALIGN (__memcpy_falkor, 6)
> +ENTRY (__memcpy_falkor)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -198,7 +198,6 @@ L(loop64):
>         ret
> 
>  END (__memcpy_falkor)
> -libc_hidden_builtin_def (__memcpy_falkor)
> 
> 
>  /* RATIONALE:
> @@ -216,7 +215,7 @@ libc_hidden_builtin_def (__memcpy_falkor)
> 
>     For small and medium cases memcpy is used.  */
> 
> -ENTRY_ALIGN (__memmove_falkor, 6)
> +ENTRY (__memmove_falkor)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -311,5 +310,4 @@ L(move_long):
>  3:     ret
> 
>  END (__memmove_falkor)
> -libc_hidden_builtin_def (__memmove_falkor)
>  #endif
> diff --git a/sysdeps/aarch64/multiarch/memcpy_sve.S b/sysdeps/aarch64/multiarch/memcpy_sve.S
> index d11be6a44301af4bfd7fa4900555b769dc58d34d..2f14f9136698c5b3130482e2c15c5d4ceb198bda 100644
> --- a/sysdeps/aarch64/multiarch/memcpy_sve.S
> +++ b/sysdeps/aarch64/multiarch/memcpy_sve.S
> @@ -141,7 +141,6 @@ L(copy64_from_end):
>         ret
> 
>  END (__memcpy_sve)
> -libc_hidden_builtin_def (__memcpy_sve)
> 
> 
>  ENTRY (__memmove_sve)
> @@ -208,5 +207,4 @@ L(return):
>         ret
> 
>  END (__memmove_sve)
> -libc_hidden_builtin_def (__memmove_sve)
>  #endif
> diff --git a/sysdeps/aarch64/multiarch/memcpy_thunderx.S b/sysdeps/aarch64/multiarch/memcpy_thunderx.S
> index 366287587f4aec5c00c35320fd1f862e45400d08..14269b1a47137f178e289e31026ab2874ccc3173 100644
> --- a/sysdeps/aarch64/multiarch/memcpy_thunderx.S
> +++ b/sysdeps/aarch64/multiarch/memcpy_thunderx.S
> @@ -65,21 +65,7 @@
>     Overlapping large forward memmoves use a loop that copies backwards.
>  */
> 
> -#ifndef MEMMOVE
> -# define MEMMOVE memmove
> -#endif
> -#ifndef MEMCPY
> -# define MEMCPY memcpy
> -#endif
> -
> -#if IS_IN (libc)
> -
> -#  undef MEMCPY
> -#  define MEMCPY __memcpy_thunderx
> -#  undef MEMMOVE
> -#  define MEMMOVE __memmove_thunderx
> -
> -ENTRY_ALIGN (MEMMOVE, 6)
> +ENTRY (__memmove_thunderx)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -91,9 +77,9 @@ ENTRY_ALIGN (MEMMOVE, 6)
>         b.lo    L(move_long)
> 
>         /* Common case falls through into memcpy.  */
> -END (MEMMOVE)
> -libc_hidden_builtin_def (MEMMOVE)
> -ENTRY (MEMCPY)
> +END (__memmove_thunderx)
> +
> +ENTRY (__memcpy_thunderx)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -316,7 +302,4 @@ L(move_long):
>         stp     C_l, C_h, [dstin]
>  3:     ret
> 
> -END (MEMCPY)
> -libc_hidden_builtin_def (MEMCPY)
> -
> -#endif
> +END (__memcpy_thunderx)
> diff --git a/sysdeps/aarch64/multiarch/memcpy_thunderx2.S b/sysdeps/aarch64/multiarch/memcpy_thunderx2.S
> index d3d6f1debcc936b81aa62b170969b149faa9913d..93993b9e03b95075dbc9aef13f44c2b9a2b7800f 100644
> --- a/sysdeps/aarch64/multiarch/memcpy_thunderx2.S
> +++ b/sysdeps/aarch64/multiarch/memcpy_thunderx2.S
> @@ -75,27 +75,12 @@
>  #define I_v    v16
>  #define J_v    v17
> 
> -#ifndef MEMMOVE
> -# define MEMMOVE memmove
> -#endif
> -#ifndef MEMCPY
> -# define MEMCPY memcpy
> -#endif
> -
> -#if IS_IN (libc)
> -
> -#undef MEMCPY
> -#define MEMCPY __memcpy_thunderx2
> -#undef MEMMOVE
> -#define MEMMOVE __memmove_thunderx2
> -
> -
>  /* Overlapping large forward memmoves use a loop that copies backwards.
>     Otherwise memcpy is used. Small moves branch to memcopy16 directly.
>     The longer memcpy cases fall through to the memcpy head.
>  */
> 
> -ENTRY_ALIGN (MEMMOVE, 6)
> +ENTRY (__memmove_thunderx2)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -109,8 +94,7 @@ ENTRY_ALIGN (MEMMOVE, 6)
>         ccmp    tmp1, count, 2, hi
>         b.lo    L(move_long)
> 
> -END (MEMMOVE)
> -libc_hidden_builtin_def (MEMMOVE)
> +END (__memmove_thunderx2)
> 
> 
>  /* Copies are split into 3 main cases: small copies of up to 16 bytes,
> @@ -124,8 +108,7 @@ libc_hidden_builtin_def (MEMMOVE)
> 
>  #define MEMCPY_PREFETCH_LDR 640
> 
> -       .p2align 4
> -ENTRY (MEMCPY)
> +ENTRY (__memcpy_thunderx2)
> 
>         PTR_ARG (0)
>         PTR_ARG (1)
> @@ -449,7 +432,7 @@ L(move_long):
>  3:     ret
> 
> 
> -END (MEMCPY)
> +END (__memcpy_thunderx2)
>         .section        .rodata
>         .p2align        4
> 
> @@ -472,6 +455,3 @@ L(ext_table):
>         .word   L(ext_size_13) -.
>         .word   L(ext_size_14) -.
>         .word   L(ext_size_15) -.
> -
> -libc_hidden_builtin_def (MEMCPY)
> -#endif
> diff --git a/sysdeps/aarch64/multiarch/memset_a64fx.S b/sysdeps/aarch64/multiarch/memset_a64fx.S
> index d520355143ead2acdaf6a7e1652d2417df8087e8..7176f3d284ab12f7a354781db668c0520f47702d 100644
> --- a/sysdeps/aarch64/multiarch/memset_a64fx.S
> +++ b/sysdeps/aarch64/multiarch/memset_a64fx.S
> @@ -33,8 +33,6 @@
>  #define vector_length  x9
> 
>  #if HAVE_AARCH64_SVE_ASM
> -# if IS_IN (libc)
> -#  define MEMSET __memset_a64fx
> 
>         .arch armv8.2-a+sve
> 
> @@ -49,7 +47,7 @@
>  #undef BTI_C
>  #define BTI_C
> 
> -ENTRY (MEMSET)
> +ENTRY (__memset_a64fx)
>         PTR_ARG (0)
>         SIZE_ARG (2)
> 
> @@ -166,8 +164,6 @@ L(L2):
>         add     count, count, CACHE_LINE_SIZE
>         b       L(last)
> 
> -END (MEMSET)
> -libc_hidden_builtin_def (MEMSET)
> +END (__memset_a64fx)
> 
> -#endif /* IS_IN (libc) */
>  #endif /* HAVE_AARCH64_SVE_ASM */
> diff --git a/sysdeps/aarch64/multiarch/memset_base64.S b/sysdeps/aarch64/multiarch/memset_base64.S
> index 35296a6dec4944fa74af176bf280e17b11a027fd..0e8f709fa58478d6e9d62020c576bb9be108866c 100644
> --- a/sysdeps/aarch64/multiarch/memset_base64.S
> +++ b/sysdeps/aarch64/multiarch/memset_base64.S
> @@ -34,7 +34,7 @@
>   *
>   */
> 
> -ENTRY_ALIGN (MEMSET, 6)
> +ENTRY (MEMSET)
> 
>         PTR_ARG (0)
>         SIZE_ARG (2)
> @@ -183,4 +183,3 @@ L(zva_64):
>  #endif
> 
>  END (MEMSET)
> -libc_hidden_builtin_def (MEMSET)
> diff --git a/sysdeps/aarch64/multiarch/memset_emag.S b/sysdeps/aarch64/multiarch/memset_emag.S
> index 17d609cead96030fbd42f2997d081c6740396af3..6fecad4fae699f9967da94ddc88867afd5c59414 100644
> --- a/sysdeps/aarch64/multiarch/memset_emag.S
> +++ b/sysdeps/aarch64/multiarch/memset_emag.S
> @@ -19,8 +19,7 @@
> 
>  #include <sysdep.h>
> 
> -#if IS_IN (libc)
> -# define MEMSET __memset_emag
> +#define MEMSET __memset_emag
> 
>  /*
>   * Using DC ZVA to zero memory does not produce better performance if
> @@ -30,7 +29,6 @@
>   * workloads.
>   */
> 
> -# define DC_ZVA_THRESHOLD 0
> +#define DC_ZVA_THRESHOLD 0
> 
> -# include "./memset_base64.S"
> -#endif
> +#include "./memset_base64.S"
> diff --git a/sysdeps/aarch64/multiarch/memset_generic.S b/sysdeps/aarch64/multiarch/memset_generic.S
> index 9c23e482bf90d8b466d3e3d1e2d2d4a053b434bb..6c1f0daac8615c3e83e067db9b61e77c1c2c2fdd 100644
> --- a/sysdeps/aarch64/multiarch/memset_generic.S
> +++ b/sysdeps/aarch64/multiarch/memset_generic.S
> @@ -21,9 +21,15 @@
> 
>  #if IS_IN (libc)
>  # define MEMSET __memset_generic
> +
> +/* Do not hide the generic version of memset, we use it internally.  */
> +# undef libc_hidden_builtin_def
> +# define libc_hidden_builtin_def(name)
> +
>  /* Add a hidden definition for use within libc.so.  */
>  # ifdef SHARED
>         .globl __GI_memset; __GI_memset = __memset_generic
>  # endif
> -# include <sysdeps/aarch64/memset.S>
>  #endif
> +
> +#include <../memset.S>
> diff --git a/sysdeps/aarch64/multiarch/memset_kunpeng.S b/sysdeps/aarch64/multiarch/memset_kunpeng.S
> index 86c46434fdd30460d0655850d25f69d75b193b2e..4a54373398ff14151c49490c06749277de664cd9 100644
> --- a/sysdeps/aarch64/multiarch/memset_kunpeng.S
> +++ b/sysdeps/aarch64/multiarch/memset_kunpeng.S
> @@ -20,16 +20,13 @@
>  #include <sysdep.h>
>  #include <sysdeps/aarch64/memset-reg.h>
> 
> -#if IS_IN (libc)
> -# define MEMSET __memset_kunpeng
> -
>  /* Assumptions:
>   *
>   * ARMv8-a, AArch64, unaligned accesses
>   *
>   */
> 
> -ENTRY_ALIGN (MEMSET, 6)
> +ENTRY (__memset_kunpeng)
> 
>         PTR_ARG (0)
>         SIZE_ARG (2)
> @@ -108,6 +105,4 @@ L(set_long):
>         stp     q0, q0, [dstend, -32]
>         ret
> 
> -END (MEMSET)
> -libc_hidden_builtin_def (MEMSET)
> -#endif
> +END (__memset_kunpeng)
> diff --git a/sysdeps/aarch64/multiarch/rtld-memset.S b/sysdeps/aarch64/multiarch/rtld-memset.S
> deleted file mode 100644
> index 4b035ed8b2cfc80cc37babe6cb2f146804feb46f..0000000000000000000000000000000000000000
> --- a/sysdeps/aarch64/multiarch/rtld-memset.S
> +++ /dev/null
> @@ -1,25 +0,0 @@
> -/* Memset for aarch64, for the dynamic linker.
> -   Copyright (C) 2017-2023 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/>.  */
> -
> -#include <sysdep.h>
> -
> -#if IS_IN (rtld)
> -# define MEMSET memset
> -# include <sysdeps/aarch64/memset.S>
> -#endif
> diff --git a/sysdeps/aarch64/multiarch/strlen.c b/sysdeps/aarch64/multiarch/strlen.c
> index bbdd3de8c4a8dca2e86f6fcfbe810be2fb1867b1..728bd1936a218c77f931c7327d402bcc873c50f9 100644
> --- a/sysdeps/aarch64/multiarch/strlen.c
> +++ b/sysdeps/aarch64/multiarch/strlen.c
> @@ -28,10 +28,10 @@
> 
>  extern __typeof (__redirect_strlen) __strlen;
> 
> -extern __typeof (__redirect_strlen) __strlen_mte attribute_hidden;
> +extern __typeof (__redirect_strlen) __strlen_generic attribute_hidden;
>  extern __typeof (__redirect_strlen) __strlen_asimd attribute_hidden;
> 
> -libc_ifunc (__strlen, (mte ? __strlen_mte : __strlen_asimd));
> +libc_ifunc (__strlen, (mte ? __strlen_generic : __strlen_asimd));
> 
>  # undef strlen
>  strong_alias (__strlen, strlen);
> diff --git a/sysdeps/aarch64/multiarch/strlen_asimd.S b/sysdeps/aarch64/multiarch/strlen_asimd.S
> index 490439491d19c3f14b0228f42248bc8aa6e9e8bd..aee5ef9f78adb1f769dbc48ef9aae8966f120c24 100644
> --- a/sysdeps/aarch64/multiarch/strlen_asimd.S
> +++ b/sysdeps/aarch64/multiarch/strlen_asimd.S
> @@ -203,4 +203,3 @@ L(page_cross):
>         ret
> 
>  END (__strlen_asimd)
> -libc_hidden_builtin_def (__strlen_asimd)
> diff --git a/sysdeps/aarch64/multiarch/strlen_mte.S b/sysdeps/aarch64/multiarch/strlen_generic.S
> similarity index 85%
> rename from sysdeps/aarch64/multiarch/strlen_mte.S
> rename to sysdeps/aarch64/multiarch/strlen_generic.S
> index 1c1220b7675fcc83953aba9ceca79deedca9242b..2346296a188af76880435ff446b9fdd76a174072 100644
> --- a/sysdeps/aarch64/multiarch/strlen_mte.S
> +++ b/sysdeps/aarch64/multiarch/strlen_generic.S
> @@ -17,14 +17,14 @@
>     <https://www.gnu.org/licenses/>.  */
> 
>  /* The actual strlen code is in ../strlen.S.  If we are building libc this file
> -   defines __strlen_mte.  Otherwise the include of ../strlen.S will define
> -   the normal __strlen  entry points.  */
> +   defines __strlen_generic.  Otherwise the include of ../strlen.S will define
> +   the normal __strlen entry points.  */
> 
>  #include <sysdep.h>
> 
>  #if IS_IN (libc)
> 
> -# define STRLEN __strlen_mte
> +# define STRLEN __strlen_generic
> 
>  /* Do not hide the generic version of strlen, we use it internally.  */
>  # undef libc_hidden_builtin_def
> @@ -32,7 +32,7 @@
> 
>  # ifdef SHARED
>  /* It doesn't make sense to send libc-internal strlen calls through a PLT. */
> -       .globl __GI_strlen; __GI_strlen = __strlen_mte
> +       .globl __GI_strlen; __GI_strlen = __strlen_generic
>  # endif
>  #endif
> 

      reply	other threads:[~2023-11-01 13:23 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-24 12:33 Wilco Dijkstra
2023-11-01 13:23 ` Szabolcs Nagy [this message]

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