From patchwork Sun Jun 11 13:50:42 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "H.J. Lu" X-Patchwork-Id: 20912 Received: (qmail 112353 invoked by alias); 11 Jun 2017 13:50:46 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 112338 invoked by uid 89); 11 Jun 2017 13:50:45 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.8 required=5.0 tests=BAYES_00, FREEMAIL_FROM, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_STOCKGEN, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mail-pg0-f65.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:subject:message-id:mime-version :content-disposition:user-agent; bh=NuqQUGsIXpxQ/9eji7zWsSGqXYgemOES9AG/rLYC+lk=; b=unsnu/nHaSWpihva5Yb1I139cTmLsjsQP5vADei5ew19FSFmmQmsHFcW2IlIMBEGnO MO5VHZxjgN1AfHsrl05Xa0BygTzUiRthJzfr7Ua2Ux8BZhbXAfRAbd88RPlktI5hxXqP nET/DltB01kUEp1gPhKde3FOrjAtsAG1TTcu3pNmQBJQKzx1hIIM7PGaPyv9YBl7dx83 dWQoxMpE3ec59kntxU7cOKVhCe8v7aA3mL4Hw2Mfv5fBGnmYBw7UDnBTU7gEu4Lx6aJm l8ULtJWrUtiZGGFbERMPP0gLAxEu1cl4ow/rgXFvpEUY7yWenxaf7p+rnoIgaAN+1GZh O5LQ== X-Gm-Message-State: AODbwcDQg0Hqi2GOHnq2SKdAbu1CFgA4I5VKzqdVX1KDJJqmcfQLBVKz h3qe+SyTPNJ7vlA7 X-Received: by 10.84.248.78 with SMTP id e14mr37191979pln.118.1497189044478; Sun, 11 Jun 2017 06:50:44 -0700 (PDT) Date: Sun, 11 Jun 2017 06:50:42 -0700 From: "H.J. Lu" To: GNU C Library Subject: [PATCH] x86-64: Implement strcpy family IFUNC selectors in C Message-ID: <20170611135042.GA22931@gmail.com> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.8.0 (2017-02-23) Implement strcpy family IFUNC selectors in C. All internal calls within libc.so can use IFUNC on x86-64 since unlike x86, x86-64 doesn't need to reserve a register to make a PLT call. For libc,a, we can't use IFUNC for functions which are called before IFUNC has been initialized. Use IFUNC internally reduces the icache footprint since libc.so and other codes in the process use the same implementations. The patch uses IFUNC for strcpy family functions within libc. Any comments? H.J. --- * sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add strcpy-sse2 and stpcpy-sse2. * sysdeps/x86_64/multiarch/ifunc-strcpy.h: New file. * sysdeps/x86_64/multiarch/stpcpy-sse2.S: Likewise. * sysdeps/x86_64/multiarch/stpcpy.c: Likewise. * sysdeps/x86_64/multiarch/stpncpy.c: Likewise. * sysdeps/x86_64/multiarch/strcpy-sse2.S: Likewise. * sysdeps/x86_64/multiarch/strcpy.c: Likewise. * sysdeps/x86_64/multiarch/strncpy.c: Likewise. * sysdeps/x86_64/multiarch/stpcpy.S: Removed. * sysdeps/x86_64/multiarch/stpncpy.S: Likewise. * sysdeps/x86_64/multiarch/strcpy.S: Likewise. * sysdeps/x86_64/multiarch/strncpy.S: Likewise. * sysdeps/x86_64/multiarch/stpncpy-c.c (weak_alias): New. (libc_hidden_def): Always defined as empty. * sysdeps/x86_64/multiarch/strncpy-c.c (libc_hidden_builtin_def): Always Defined as empty. --- sysdeps/x86_64/multiarch/Makefile | 1 + sysdeps/x86_64/multiarch/ifunc-strcpy.h | 39 +++++++++++++ sysdeps/x86_64/multiarch/stpcpy-sse2.S | 33 +++++++++++ sysdeps/x86_64/multiarch/stpcpy.S | 9 --- sysdeps/x86_64/multiarch/stpcpy.c | 40 +++++++++++++ sysdeps/x86_64/multiarch/stpncpy-c.c | 9 ++- sysdeps/x86_64/multiarch/stpncpy.S | 8 --- sysdeps/x86_64/multiarch/stpncpy.c | 37 ++++++++++++ sysdeps/x86_64/multiarch/strcpy-sse2.S | 29 ++++++++++ sysdeps/x86_64/multiarch/strcpy.S | 99 --------------------------------- sysdeps/x86_64/multiarch/strcpy.c | 34 +++++++++++ sysdeps/x86_64/multiarch/strncpy-c.c | 7 +-- sysdeps/x86_64/multiarch/strncpy.S | 5 -- sysdeps/x86_64/multiarch/strncpy.c | 35 ++++++++++++ 14 files changed, 254 insertions(+), 131 deletions(-) create mode 100644 sysdeps/x86_64/multiarch/ifunc-strcpy.h create mode 100644 sysdeps/x86_64/multiarch/stpcpy-sse2.S delete mode 100644 sysdeps/x86_64/multiarch/stpcpy.S create mode 100644 sysdeps/x86_64/multiarch/stpcpy.c delete mode 100644 sysdeps/x86_64/multiarch/stpncpy.S create mode 100644 sysdeps/x86_64/multiarch/stpncpy.c create mode 100644 sysdeps/x86_64/multiarch/strcpy-sse2.S delete mode 100644 sysdeps/x86_64/multiarch/strcpy.S create mode 100644 sysdeps/x86_64/multiarch/strcpy.c delete mode 100644 sysdeps/x86_64/multiarch/strncpy.S create mode 100644 sysdeps/x86_64/multiarch/strncpy.c diff --git a/sysdeps/x86_64/multiarch/Makefile b/sysdeps/x86_64/multiarch/Makefile index 7d7c142..ff6c7f4 100644 --- a/sysdeps/x86_64/multiarch/Makefile +++ b/sysdeps/x86_64/multiarch/Makefile @@ -19,6 +19,7 @@ sysdep_routines += strncat-c stpncpy-c strncpy-c strcmp-ssse3 \ strrchr-sse2 strrchr-avx2 \ strlen-sse2 strnlen-sse2 strlen-avx2 strnlen-avx2 \ strncase_l-ssse3 strcat-ssse3 strncat-ssse3\ + strcpy-sse2 stpcpy-sse2 \ strcpy-ssse3 strncpy-ssse3 stpcpy-ssse3 stpncpy-ssse3 \ strcpy-sse2-unaligned strncpy-sse2-unaligned \ stpcpy-sse2-unaligned stpncpy-sse2-unaligned \ diff --git a/sysdeps/x86_64/multiarch/ifunc-strcpy.h b/sysdeps/x86_64/multiarch/ifunc-strcpy.h new file mode 100644 index 0000000..b6c8b63 --- /dev/null +++ b/sysdeps/x86_64/multiarch/ifunc-strcpy.h @@ -0,0 +1,39 @@ +/* Common definition for ifunc implementation. + All versions must be listed in ifunc-impl-list.c. + Copyright (C) 2017 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 + . */ + +#include + +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden; +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned) + attribute_hidden; +extern __typeof (REDIRECT_NAME) OPTIMIZE (ssse3) attribute_hidden; + +static inline void * +IFUNC_SELECTOR (void) +{ + const struct cpu_features* cpu_features = __get_cpu_features (); + + if (CPU_FEATURES_ARCH_P (cpu_features, Fast_Unaligned_Load)) + return OPTIMIZE (sse2_unaligned); + + if (CPU_FEATURES_CPU_P (cpu_features, SSSE3)) + return OPTIMIZE (ssse3); + + return OPTIMIZE (sse2); +} diff --git a/sysdeps/x86_64/multiarch/stpcpy-sse2.S b/sysdeps/x86_64/multiarch/stpcpy-sse2.S new file mode 100644 index 0000000..701ff68 --- /dev/null +++ b/sysdeps/x86_64/multiarch/stpcpy-sse2.S @@ -0,0 +1,33 @@ +/* stpcpy optimized with SSE2. + Copyright (C) 2017 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 + . */ + +#if IS_IN (libc) + +# include +# define __stpcpy __stpcpy_sse2 + +# undef weak_alias +# define weak_alias(__stpcpy, stpcpy) +# undef libc_hidden_def +# define libc_hidden_def(__stpcpy) +# undef libc_hidden_builtin_def +# define libc_hidden_builtin_def(stpcpy) +#endif + +#define USE_AS_STPCPY +#include "../stpcpy.S" diff --git a/sysdeps/x86_64/multiarch/stpcpy.S b/sysdeps/x86_64/multiarch/stpcpy.S deleted file mode 100644 index ee81ab6..0000000 --- a/sysdeps/x86_64/multiarch/stpcpy.S +++ /dev/null @@ -1,9 +0,0 @@ -/* Multiple versions of stpcpy - All versions must be listed in ifunc-impl-list.c. */ -#define USE_AS_STPCPY -#define STRCPY __stpcpy -#include "strcpy.S" - -weak_alias (__stpcpy, stpcpy) -libc_hidden_def (__stpcpy) -libc_hidden_builtin_def (stpcpy) diff --git a/sysdeps/x86_64/multiarch/stpcpy.c b/sysdeps/x86_64/multiarch/stpcpy.c new file mode 100644 index 0000000..85b59d0 --- /dev/null +++ b/sysdeps/x86_64/multiarch/stpcpy.c @@ -0,0 +1,40 @@ +/* Multiple versions of stpcpy. + All versions must be listed in ifunc-impl-list.c. + Copyright (C) 2017 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 + . */ + +/* Define multiple versions only for the definition in libc. */ +#if IS_IN (libc) +# define _HAVE_STRING_ARCH_stpcpy +# define stpcpy __redirect_stpcpy +# define __stpcpy __redirect___stpcpy +# include +# undef stpcpy +# undef __stpcpy + +# define SYMBOL_NAME stpcpy +# include "ifunc-strcpy.h" + +libc_ifunc_redirected (__redirect_stpcpy, __stpcpy, IFUNC_SELECTOR ()); +# ifdef SHARED +weak_alias (__stpcpy, stpcpy) +__hidden_ver1 (__stpcpy, __GI___stpcpy, __redirect___stpcpy) + __attribute__((visibility ("hidden"))); +__hidden_ver1 (stpcpy, __GI_stpcpy, __redirect_stpcpy) + __attribute__((visibility ("hidden"))); +# endif +#endif diff --git a/sysdeps/x86_64/multiarch/stpncpy-c.c b/sysdeps/x86_64/multiarch/stpncpy-c.c index 2fde77d..62f69b5 100644 --- a/sysdeps/x86_64/multiarch/stpncpy-c.c +++ b/sysdeps/x86_64/multiarch/stpncpy-c.c @@ -1,8 +1,7 @@ #define STPNCPY __stpncpy_sse2 -#ifdef SHARED +#undef weak_alias +#define weak_alias(__stpncpy, stpncpy) #undef libc_hidden_def -#define libc_hidden_def(name) \ - __hidden_ver1 (__stpncpy_sse2, __GI___stpncpy, __stpncpy_sse2); -#endif +#define libc_hidden_def(stpncpy) -#include "stpncpy.c" +#include diff --git a/sysdeps/x86_64/multiarch/stpncpy.S b/sysdeps/x86_64/multiarch/stpncpy.S deleted file mode 100644 index 2698ca6..0000000 --- a/sysdeps/x86_64/multiarch/stpncpy.S +++ /dev/null @@ -1,8 +0,0 @@ -/* Multiple versions of stpncpy - All versions must be listed in ifunc-impl-list.c. */ -#define STRCPY __stpncpy -#define USE_AS_STPCPY -#define USE_AS_STRNCPY -#include "strcpy.S" - -weak_alias (__stpncpy, stpncpy) diff --git a/sysdeps/x86_64/multiarch/stpncpy.c b/sysdeps/x86_64/multiarch/stpncpy.c new file mode 100644 index 0000000..0e3822a --- /dev/null +++ b/sysdeps/x86_64/multiarch/stpncpy.c @@ -0,0 +1,37 @@ +/* Multiple versions of stpncpy. + All versions must be listed in ifunc-impl-list.c. + Copyright (C) 2017 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 + . */ + +/* Define multiple versions only for the definition in libc. */ +#if IS_IN (libc) +# define stpncpy __redirect_stpncpy +# define __stpncpy __redirect___stpncpy +# include +# undef stpncpy +# undef __stpncpy + +# define SYMBOL_NAME stpncpy +# include "ifunc-strcpy.h" + +libc_ifunc_redirected (__redirect_stpncpy, __stpncpy, IFUNC_SELECTOR ()); +# ifdef SHARED +weak_alias (__stpncpy, stpncpy) +__hidden_ver1 (__stpncpy, __GI___stpncpy, __redirect___stpncpy) + __attribute__((visibility ("hidden"))); +# endif +#endif diff --git a/sysdeps/x86_64/multiarch/strcpy-sse2.S b/sysdeps/x86_64/multiarch/strcpy-sse2.S new file mode 100644 index 0000000..d6c9a35 --- /dev/null +++ b/sysdeps/x86_64/multiarch/strcpy-sse2.S @@ -0,0 +1,29 @@ +/* strcpy optimized with SSE2. + Copyright (C) 2009-2017 Free Software Foundation, Inc. + Contributed by Intel Corporation. + 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 + . */ + +#if IS_IN (libc) + +# include +# define strcpy __strcpy_sse2 + +# undef libc_hidden_builtin_def +# define libc_hidden_builtin_def(strcpy) +#endif + +#include "../strcpy.S" diff --git a/sysdeps/x86_64/multiarch/strcpy.S b/sysdeps/x86_64/multiarch/strcpy.S deleted file mode 100644 index 77819dd..0000000 --- a/sysdeps/x86_64/multiarch/strcpy.S +++ /dev/null @@ -1,99 +0,0 @@ -/* Multiple versions of strcpy - All versions must be listed in ifunc-impl-list.c. - Copyright (C) 2009-2017 Free Software Foundation, Inc. - Contributed by Intel Corporation. - 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 - . */ - -#include -#include - -#if !defined (USE_AS_STPCPY) && !defined (USE_AS_STRNCPY) -# ifndef STRCPY -# define STRCPY strcpy -# endif -#endif - -#ifdef USE_AS_STPCPY -# ifdef USE_AS_STRNCPY -# define STRCPY_SSSE3 __stpncpy_ssse3 -# define STRCPY_SSE2 __stpncpy_sse2 -# define STRCPY_SSE2_UNALIGNED __stpncpy_sse2_unaligned -# define __GI_STRCPY __GI_stpncpy -# define __GI___STRCPY __GI___stpncpy -# else -# define STRCPY_SSSE3 __stpcpy_ssse3 -# define STRCPY_SSE2 __stpcpy_sse2 -# define STRCPY_SSE2_UNALIGNED __stpcpy_sse2_unaligned -# define __GI_STRCPY __GI_stpcpy -# define __GI___STRCPY __GI___stpcpy -# endif -#else -# ifdef USE_AS_STRNCPY -# define STRCPY_SSSE3 __strncpy_ssse3 -# define STRCPY_SSE2 __strncpy_sse2 -# define STRCPY_SSE2_UNALIGNED __strncpy_sse2_unaligned -# define __GI_STRCPY __GI_strncpy -# else -# define STRCPY_SSSE3 __strcpy_ssse3 -# define STRCPY_SSE2 __strcpy_sse2 -# define STRCPY_SSE2_UNALIGNED __strcpy_sse2_unaligned -# define __GI_STRCPY __GI_strcpy -# endif -#endif - - -/* Define multiple versions only for the definition in libc. */ -#if IS_IN (libc) - .text -ENTRY(STRCPY) - .type STRCPY, @gnu_indirect_function - LOAD_RTLD_GLOBAL_RO_RDX - leaq STRCPY_SSE2_UNALIGNED(%rip), %rax - HAS_ARCH_FEATURE (Fast_Unaligned_Load) - jnz 2f - leaq STRCPY_SSE2(%rip), %rax - HAS_CPU_FEATURE (SSSE3) - jz 2f - leaq STRCPY_SSSE3(%rip), %rax -2: ret -END(STRCPY) - -# undef ENTRY -# define ENTRY(name) \ - .type STRCPY_SSE2, @function; \ - .align 16; \ - .globl STRCPY_SSE2; \ - .hidden STRCPY_SSE2; \ - STRCPY_SSE2: cfi_startproc; \ - CALL_MCOUNT -# undef END -# define END(name) \ - cfi_endproc; .size STRCPY_SSE2, .-STRCPY_SSE2 -# undef libc_hidden_builtin_def -/* It doesn't make sense to send libc-internal strcpy calls through a PLT. - The speedup we get from using SSSE3 instruction is likely eaten away - by the indirect call in the PLT. */ -# define libc_hidden_builtin_def(name) \ - .globl __GI_STRCPY; __GI_STRCPY = STRCPY_SSE2 -# undef libc_hidden_def -# define libc_hidden_def(name) \ - .globl __GI___STRCPY; __GI___STRCPY = STRCPY_SSE2 -#endif - -#ifndef USE_AS_STRNCPY -#include "../strcpy.S" -#endif diff --git a/sysdeps/x86_64/multiarch/strcpy.c b/sysdeps/x86_64/multiarch/strcpy.c new file mode 100644 index 0000000..3bd552e --- /dev/null +++ b/sysdeps/x86_64/multiarch/strcpy.c @@ -0,0 +1,34 @@ +/* Multiple versions of strcpy. + All versions must be listed in ifunc-impl-list.c. + Copyright (C) 2017 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 + . */ + +/* Define multiple versions only for the definition in libc. */ +#if IS_IN (libc) +# define strcpy __redirect_strcpy +# include +# undef strcpy + +# define SYMBOL_NAME strcpy +# include "ifunc-strcpy.h" + +libc_ifunc_redirected (__redirect_strcpy, strcpy, IFUNC_SELECTOR ()); +# ifdef SHARED +__hidden_ver1 (strcpy, __GI_strcpy, __redirect_strcpy) + __attribute__((visibility ("hidden"))); +# endif +#endif diff --git a/sysdeps/x86_64/multiarch/strncpy-c.c b/sysdeps/x86_64/multiarch/strncpy-c.c index 296c32c..57c45ac 100644 --- a/sysdeps/x86_64/multiarch/strncpy-c.c +++ b/sysdeps/x86_64/multiarch/strncpy-c.c @@ -1,8 +1,5 @@ #define STRNCPY __strncpy_sse2 -#ifdef SHARED #undef libc_hidden_builtin_def -#define libc_hidden_builtin_def(name) \ - __hidden_ver1 (__strncpy_sse2, __GI_strncpy, __strncpy_sse2); -#endif +#define libc_hidden_builtin_def(strncpy) -#include "strncpy.c" +#include diff --git a/sysdeps/x86_64/multiarch/strncpy.S b/sysdeps/x86_64/multiarch/strncpy.S deleted file mode 100644 index 6d87a0b..0000000 --- a/sysdeps/x86_64/multiarch/strncpy.S +++ /dev/null @@ -1,5 +0,0 @@ -/* Multiple versions of strncpy - All versions must be listed in ifunc-impl-list.c. */ -#define STRCPY strncpy -#define USE_AS_STRNCPY -#include "strcpy.S" diff --git a/sysdeps/x86_64/multiarch/strncpy.c b/sysdeps/x86_64/multiarch/strncpy.c new file mode 100644 index 0000000..5340851 --- /dev/null +++ b/sysdeps/x86_64/multiarch/strncpy.c @@ -0,0 +1,35 @@ +/* Multiple versions of strncpy. + All versions must be listed in ifunc-impl-list.c. + Copyright (C) 2017 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 + . */ + +/* Define multiple versions only for the definition in libc. */ +#if IS_IN (libc) +# define _HAVE_STRING_ARCH_strncpy +# define strncpy __redirect_strncpy +# include +# undef strncpy + +# define SYMBOL_NAME strncpy +# include "ifunc-strcpy.h" + +libc_ifunc_redirected (__redirect_strncpy, strncpy, IFUNC_SELECTOR ()); +# ifdef SHARED +__hidden_ver1 (strncpy, __GI_strncpy, __redirect_strncpy) + __attribute__((visibility ("hidden"))); +# endif +#endif