32bit memcmp/strcmp/strncmp optimized for SSSE3/SSS4.2

1 files changed, 115 insertions, 0 deletions

diff --git a/sysdeps/i386/i686/multiarch/strcmp.S b/sysdeps/i386/i686/multiarch/strcmp.S
new file mode 100644
index 0000000000..79a1fdfd43
--- /dev/null
+++ b/sysdeps/i386/i686/multiarch/strcmp.S
@@ -0,0 +1,115 @@
+/* Multiple versions of strcmp
+   Copyright (C) 2010 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+#include <init-arch.h>
+
+#ifndef USE_AS_STRNCMP
+# define STRCMP			strcmp
+# define __GI_STRCMP		__GI_strcmp
+# define __STRCMP_IA32		__strcmp_ia32
+# define __STRCMP_SSSE3		__strcmp_ssse3
+# define __STRCMP_SSE4_2	__strcmp_sse4_2
+#else
+# define STRCMP			strncmp
+# define __GI_STRCMP		__GI_strncmp
+# define __STRCMP_IA32		__strncmp_ia32
+# define __STRCMP_SSSE3		__strncmp_ssse3
+# define __STRCMP_SSE4_2	__strncmp_sse4_2
+#endif
+
+/* Define multiple versions only for the definition in libc.  Don't
+   define multiple versions for strncmp in static library since we
+   need strncmp before the initialization happened.  */
+#if (defined SHARED || !defined USE_AS_STRNCMP) && !defined NOT_IN_libc
+# ifdef SHARED
+	.section	.gnu.linkonce.t.__i686.get_pc_thunk.bx,"ax",@progbits
+	.globl	__i686.get_pc_thunk.bx
+	.hidden	__i686.get_pc_thunk.bx
+	.p2align 4
+	.type	__i686.get_pc_thunk.bx,@function
+__i686.get_pc_thunk.bx:
+	movl	(%esp), %ebx
+	ret
+
+	.text
+ENTRY(STRCMP)
+	.type	STRCMP, @gnu_indirect_function
+	pushl	%ebx
+	cfi_adjust_cfa_offset (4)
+	cfi_rel_offset (ebx, 0)
+	call	__i686.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	cmpl	$0, KIND_OFFSET+__cpu_features@GOTOFF(%ebx)
+	jne	1f
+	call	__init_cpu_features
+1:	leal	__STRCMP_IA32@GOTOFF(%ebx), %eax
+	testl	$bit_SSSE3, CPUID_OFFSET+index_SSSE3+__cpu_features@GOTOFF(%ebx)
+	jz	2f
+	leal	__STRCMP_SSSE3@GOTOFF(%ebx), %eax
+	testl	$bit_SSE4_2, CPUID_OFFSET+index_SSE4_2+__cpu_features@GOTOFF(%ebx)
+	jz	2f
+	leal	__STRCMP_SSE4_2@GOTOFF(%ebx), %eax
+2:	popl	%ebx
+	cfi_adjust_cfa_offset (-4)
+	cfi_restore (ebx)
+	ret
+END(STRCMP)
+# else
+	.text
+ENTRY(STRCMP)
+	.type	STRCMP, @gnu_indirect_function
+	cmpl	$0, KIND_OFFSET+__cpu_features
+	jne	1f
+	call	__init_cpu_features
+1:	leal	__STRCMP_IA32, %eax
+	testl	$bit_SSSE3, CPUID_OFFSET+index_SSSE3+__cpu_features
+	jz	2f
+	leal	__STRCMP_SSSE3, %eax
+	testl	$bit_SSE4_2, FEATURE_OFFSET+index_SSE4_2+__cpu_features
+	jz	2f
+	leal	__STRCMP_SSE4_2, %eax
+2:	ret
+END(STRCMP)
+# endif
+
+# undef ENTRY
+# define ENTRY(name) \
+	.type __STRCMP_IA32, @function; \
+	.p2align 4; \
+	__STRCMP_IA32: cfi_startproc; \
+	CALL_MCOUNT
+# undef END
+# define END(name) \
+	cfi_endproc; .size __STRCMP_IA32, .-__STRCMP_IA32
+
+# ifdef SHARED
+#  undef libc_hidden_builtin_def
+/* IFUNC doesn't work with the hidden functions in shared library since
+   they will be called without setting up EBX needed for PLT which is
+   used by IFUNC.  */
+#  define libc_hidden_builtin_def(name) \
+	.globl __GI_STRCMP; __GI_STRCMP = __STRCMP_IA32
+# endif
+#endif
+
+#ifndef USE_AS_STRNCMP
+# include "../strcmp.S"
+#endif