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/* Multiple versions of memcmp
   All versions must be listed in ifunc-impl-list.c.
   Copyright (C) 2010-2017 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>

/* Define multiple versions only for the definition in libc. */
#if IS_IN (libc)
	.text
ENTRY(memcmp)
	.type	memcmp, @gnu_indirect_function
	LOAD_RTLD_GLOBAL_RO_RDX
	HAS_ARCH_FEATURE (Prefer_No_VZEROUPPER)
	jnz	1f
	HAS_ARCH_FEATURE (AVX2_Usable)
	jz	1f
	HAS_CPU_FEATURE (MOVBE)
	jz	1f
	HAS_ARCH_FEATURE (AVX_Fast_Unaligned_Load)
	jz	1f
	leaq	__memcmp_avx2_movbe(%rip), %rax
	ret

1:	HAS_CPU_FEATURE (SSSE3)
	jnz	2f
	leaq	__memcmp_sse2(%rip), %rax
	ret

2:	HAS_CPU_FEATURE (SSE4_1)
	jz	3f
	leaq	__memcmp_sse4_1(%rip), %rax
	ret

3:	leaq	__memcmp_ssse3(%rip), %rax
	ret

END(memcmp)

# undef ENTRY
# define ENTRY(name) \
	.type __memcmp_sse2, @function; \
	.p2align 4; \
	.globl __memcmp_sse2; \
	.hidden __memcmp_sse2; \
	__memcmp_sse2: cfi_startproc; \
	CALL_MCOUNT
# undef END
# define END(name) \
	cfi_endproc; .size __memcmp_sse2, .-__memcmp_sse2

# ifdef SHARED
#  undef libc_hidden_builtin_def
/* It doesn't make sense to send libc-internal memcmp calls through a PLT.
   The speedup we get from using SSE4 instructions is likely eaten away
   by the indirect call in the PLT.  */
#  define libc_hidden_builtin_def(name) \
	.globl __GI_memcmp; __GI_memcmp = __memcmp_sse2
# endif
#endif

#include "../memcmp.S"