x86-64: Implement strcat family IFUNC selectors in C

Implement strcat family IFUNC selectors in C.

All internal calls within libc.so can use IFUNC on x86-64 since unlike
x86, x86-64 supports PC-relative addressing to access the GOT entry so
that it can call via PLT without using an extra register.  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.
This patch uses IFUNC for strcat family functions within libc.

	* sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
	strcat-sse2.
	* sysdeps/x86_64/multiarch/strcat-sse2.S: New file.
	* sysdeps/x86_64/multiarch/strcat.c: Likewise.
	* sysdeps/x86_64/multiarch/strncat.c: Likewise.
	* sysdeps/x86_64/multiarch/strcat.S: Removed.
	* sysdeps/x86_64/multiarch/strncat.S: Likewise.
This commit is contained in:
H.J. Lu 2017-06-15 08:56:48 -07:00
parent b91a52d0d7
commit 9ed0aa15d3
7 changed files with 105 additions and 90 deletions

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@ -1,3 +1,13 @@
2017-06-15 H.J. Lu <hongjiu.lu@intel.com>
* sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
strcat-sse2.
* sysdeps/x86_64/multiarch/strcat-sse2.S: New file.
* sysdeps/x86_64/multiarch/strcat.c: Likewise.
* sysdeps/x86_64/multiarch/strncat.c: Likewise.
* sysdeps/x86_64/multiarch/strcat.S: Removed.
* sysdeps/x86_64/multiarch/strncat.S: Likewise.
2017-06-15 H.J. Lu <hongjiu.lu@intel.com>
Erich Elsen <eriche@google.com>

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@ -23,6 +23,7 @@ sysdep_routines += strncat-c stpncpy-c strncpy-c strcmp-ssse3 \
strcpy-ssse3 strncpy-ssse3 stpcpy-ssse3 stpncpy-ssse3 \
strcpy-sse2-unaligned strncpy-sse2-unaligned \
stpcpy-sse2-unaligned stpncpy-sse2-unaligned \
strcat-sse2 \
strcat-sse2-unaligned strncat-sse2-unaligned \
strchr-sse2-no-bsf memcmp-ssse3 strstr-sse2-unaligned \
strcspn-c strpbrk-c strspn-c varshift \

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@ -0,0 +1,28 @@
/* strcat 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
<http://www.gnu.org/licenses/>. */
#if IS_IN (libc)
# include <sysdep.h>
# define strcat __strcat_sse2
# undef libc_hidden_builtin_def
# define libc_hidden_builtin_def(strcat)
#endif
#include <sysdeps/x86_64/strcat.S>

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@ -1,85 +0,0 @@
/* Multiple versions of strcat
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
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <init-arch.h>
#ifndef USE_AS_STRNCAT
# ifndef STRCAT
# define STRCAT strcat
# endif
#endif
#ifdef USE_AS_STRNCAT
# define STRCAT_SSSE3 __strncat_ssse3
# define STRCAT_SSE2 __strncat_sse2
# define STRCAT_SSE2_UNALIGNED __strncat_sse2_unaligned
# define __GI_STRCAT __GI_strncat
# define __GI___STRCAT __GI___strncat
#else
# define STRCAT_SSSE3 __strcat_ssse3
# define STRCAT_SSE2 __strcat_sse2
# define STRCAT_SSE2_UNALIGNED __strcat_sse2_unaligned
# define __GI_STRCAT __GI_strcat
# define __GI___STRCAT __GI___strcat
#endif
/* Define multiple versions only for the definition in libc. */
#if IS_IN (libc)
.text
ENTRY(STRCAT)
.type STRCAT, @gnu_indirect_function
LOAD_RTLD_GLOBAL_RO_RDX
leaq STRCAT_SSE2_UNALIGNED(%rip), %rax
HAS_ARCH_FEATURE (Fast_Unaligned_Load)
jnz 2f
leaq STRCAT_SSE2(%rip), %rax
HAS_CPU_FEATURE (SSSE3)
jz 2f
leaq STRCAT_SSSE3(%rip), %rax
2: ret
END(STRCAT)
# undef ENTRY
# define ENTRY(name) \
.type STRCAT_SSE2, @function; \
.align 16; \
.globl STRCAT_SSE2; \
.hidden STRCAT_SSE2; \
STRCAT_SSE2: cfi_startproc; \
CALL_MCOUNT
# undef END
# define END(name) \
cfi_endproc; .size STRCAT_SSE2, .-STRCAT_SSE2
# undef libc_hidden_builtin_def
/* It doesn't make sense to send libc-internal strcat 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_STRCAT; __GI_STRCAT = STRCAT_SSE2
# undef libc_hidden_def
# define libc_hidden_def(name) \
.globl __GI___STRCAT; __GI___STRCAT = STRCAT_SSE2
#endif
#ifndef USE_AS_STRNCAT
# include "../strcat.S"
#endif

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@ -0,0 +1,35 @@
/* Multiple versions of strcat.
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
<http://www.gnu.org/licenses/>. */
/* Define multiple versions only for the definition in libc. */
#if IS_IN (libc)
# define strcat __redirect_strcat
# include <string.h>
# undef strcat
# define SYMBOL_NAME strcat
# include "ifunc-unaligned-ssse3.h"
libc_ifunc_redirected (__redirect_strcat, strcat, IFUNC_SELECTOR ());
# ifdef SHARED
__hidden_ver1 (strcat, __GI_strcat, __redirect_strcat)
__attribute__ ((visibility ("hidden")));
# endif
#endif

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@ -1,5 +0,0 @@
/* Multiple versions of strncat
All versions must be listed in ifunc-impl-list.c. */
#define STRCAT strncat
#define USE_AS_STRNCAT
#include "strcat.S"

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@ -0,0 +1,31 @@
/* Multiple versions of strncat.
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
<http://www.gnu.org/licenses/>. */
/* Define multiple versions only for the definition in libc. */
#if IS_IN (libc)
# define _HAVE_STRING_ARCH_strncat 1
# define strncat __redirect_strncat
# include <string.h>
# undef strncat
# define SYMBOL_NAME strncat
# include "ifunc-unaligned-ssse3.h"
libc_ifunc_redirected (__redirect_strncat, strncat, IFUNC_SELECTOR ());
#endif