S390: Optimize strcmp and wcscmp.

This patch provides optimized versions of strcmp and wcscmp with the z13
vector instructions.

The architecture specific string.h had a typo, which leads to ommiting the
inline version in this file if __USE_STRING_INLINES is defined.
Tested this inline version by tweaking test-strcmp.c.

ChangeLog:

	* sysdeps/s390/multiarch/strcmp-vx.S: New File.
	* sysdeps/s390/multiarch/strcmp.c: Likewise.
	* sysdeps/s390/multiarch/wcscmp-c.c: Likewise.
	* sysdeps/s390/multiarch/wcscmp-vx.S: Likewise.
	* sysdeps/s390/multiarch/wcscmp.c: Likewise.
	* sysdeps/s390/s390-32/multiarch/strcmp.c: Likewise.
	* sysdeps/s390/s390-64/multiarch/strcmp.c: Likewise.
	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strcmp and
	wcscmp functions.
	* sysdeps/s390/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list): Add ifunc test for strcmp, wcscmp.
	* string/strcmp.c (STRCMP): Define and use macro.
	* benchtests/bench-wcscmp.c: New File.
	* benchtests/Makefile (wcsmbs-bench): Add wcscmp.
	* sysdeps/s390/bits/string.h: Fix typo: _HAVE_STRING_ARCH_strcmp
	instead of _HAVE_STRING_ARCH_memchr.

ChangeLog

@@ -1,3 +1,22 @@
+2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
+	* sysdeps/s390/multiarch/strcmp-vx.S: New File.
+	* sysdeps/s390/multiarch/strcmp.c: Likewise.
+	* sysdeps/s390/multiarch/wcscmp-c.c: Likewise.
+	* sysdeps/s390/multiarch/wcscmp-vx.S: Likewise.
+	* sysdeps/s390/multiarch/wcscmp.c: Likewise.
+	* sysdeps/s390/s390-32/multiarch/strcmp.c: Likewise.
+	* sysdeps/s390/s390-64/multiarch/strcmp.c: Likewise.
+	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strcmp and
+	wcscmp functions.
+	* sysdeps/s390/multiarch/ifunc-impl-list.c
+	(__libc_ifunc_impl_list): Add ifunc test for strcmp, wcscmp.
+	* string/strcmp.c (STRCMP): Define and use macro.
+	* benchtests/bench-wcscmp.c: New File.
+	* benchtests/Makefile (wcsmbs-bench): Add wcscmp.
+	* sysdeps/s390/bits/string.h: Fix typo: _HAVE_STRING_ARCH_strcmp
+	instead of _HAVE_STRING_ARCH_memchr.
+
 2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
 	* sysdeps/s390/multiarch/strncat-c.c: New File.

benchtests/Makefile

@@ -36,7 +36,8 @@ string-bench := bcopy bzero memccpy memchr memcmp memcpy memmem memmove \
 		strncasecmp strncat strncmp strncpy strnlen strpbrk strrchr \
 		strspn strstr strcpy_chk stpcpy_chk memrchr strsep strtok \
 		strcoll
-wcsmbs-bench := wcslen wcsnlen wcscpy wcpcpy wcsncpy wcpncpy wcscat wcsncat
+wcsmbs-bench := wcslen wcsnlen wcscpy wcpcpy wcsncpy wcpncpy wcscat wcsncat \
+		wcscmp
 string-bench-all := $(string-bench) ${wcsmbs-bench}
 
 # We have to generate locales

benchtests/bench-wcscmp.c

@@ -0,0 +1,20 @@
+/* Measure wcscmp functions.
+   Copyright (C) 2015 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 WIDE 1
+#include "bench-strcmp.c"

string/strcmp.c

@@ -19,11 +19,15 @@
 
 #undef strcmp
 
+#ifndef STRCMP
+# define STRCMP strcmp
+#endif
+
 /* Compare S1 and S2, returning less than, equal to or
    greater than zero if S1 is lexicographically less than,
    equal to or greater than S2.  */
 int
-strcmp (const char *p1, const char *p2)
+STRCMP (const char *p1, const char *p2)
 {
   const unsigned char *s1 = (const unsigned char *) p1;
   const unsigned char *s2 = (const unsigned char *) p2;

sysdeps/s390/bits/string.h

@@ -226,8 +226,8 @@ memchr (const void *__str, int __c, size_t __n)
 }
 #endif
 
-/* Search N bytes of S for C.  */
-#define _HAVE_STRING_ARCH_memchr 1
+/* Compare S1 and S2.  */
+#define _HAVE_STRING_ARCH_strcmp 1
 #ifndef _FORCE_INLINES
 __STRING_INLINE int
 strcmp (const char *__s1, const char *__s2)

sysdeps/s390/multiarch/Makefile

@@ -6,7 +6,8 @@ sysdep_routines += strlen strlen-vx strlen-c \
 		   strncpy strncpy-vx \
 		   stpncpy stpncpy-vx stpncpy-c \
 		   strcat strcat-vx strcat-c \
-		   strncat strncat-vx strncat-c
+		   strncat strncat-vx strncat-c \
+		   strcmp strcmp-vx
 endif
 
 ifeq ($(subdir),wcsmbs)
@@ -17,5 +18,6 @@ sysdep_routines += wcslen wcslen-vx wcslen-c \
 		   wcsncpy wcsncpy-vx wcsncpy-c \
 		   wcpncpy wcpncpy-vx wcpncpy-c \
 		   wcscat wcscat-vx wcscat-c \
-		   wcsncat wcsncat-vx wcsncat-c
+		   wcsncat wcsncat-vx wcsncat-c \
+		   wcscmp wcscmp-vx wcscmp-c
 endif

sysdeps/s390/multiarch/ifunc-impl-list.c

@@ -103,6 +103,9 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
   IFUNC_VX_IMPL (strncat);
   IFUNC_VX_IMPL (wcsncat);
 
+  IFUNC_VX_IMPL (strcmp);
+  IFUNC_VX_IMPL (wcscmp);
+
 #endif /* HAVE_S390_VX_ASM_SUPPORT */
 
   return i;

sysdeps/s390/multiarch/strcmp-vx.S

@@ -0,0 +1,116 @@
+/* Vector optimized 32/64 bit S/390 version of strcmp.
+   Copyright (C) 2015 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 defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+
+# include "sysdep.h"
+# include "asm-syntax.h"
+
+	.text
+
+/* int strcmp (const char *s1, const char *s2)
+   Compare two strings
+
+   Register usage:
+   -r1=loaded byte count s1
+   -r2=s1
+   -r3=s2
+   -r4=loaded byte coutn s2, tmp
+   -r5=current_len
+   -v16=part of s1
+   -v17=part of s2
+   -v18=index of unequal
+*/
+ENTRY(__strcmp_vx)
+	.machine "z13"
+	.machinemode "zarch_nohighgprs"
+
+	lghi	%r5,0		/* current_len = 0.  */
+
+.Lloop:
+	vlbb	%v16,0(%r5,%r2),6 /* Load s1 to block boundary.  */
+	vlbb	%v17,0(%r5,%r3),6 /* Load s2 to block boundary.  */
+	lcbb	%r1,0(%r5,%r2),6 /* Get loaded byte count of s1.  */
+	jo	.Llt16_1	/* Jump away if vr is not fully loaded.  */
+	lcbb	%r4,0(%r5,%r3),6
+	jo	.Llt16_2	/* Jump away if vr is not fully loaded.  */
+	/* Both vrs are fully loaded.  */
+	aghi	%r5,16
+	vfenezbs %v18,%v16,%v17	/* Compare not equal with zero search.  */
+	jno	.Lfound
+
+	vlbb	%v16,0(%r5,%r2),6
+	vlbb	%v17,0(%r5,%r3),6
+	lcbb	%r1,0(%r5,%r2),6
+	jo	.Llt16_1
+	lcbb	%r4,0(%r5,%r3),6
+	jo	.Llt16_2
+	aghi	%r5,16
+	vfenezbs %v18,%v16,%v17
+	jno	.Lfound
+
+	vlbb	%v16,0(%r5,%r2),6
+	vlbb	%v17,0(%r5,%r3),6
+	lcbb	%r1,0(%r5,%r2),6
+	jo	.Llt16_1
+	lcbb	%r4,0(%r5,%r3),6
+	jo	.Llt16_2
+	aghi	%r5,16
+	vfenezbs %v18,%v16,%v17
+	jno	.Lfound
+
+	vlbb	%v16,0(%r5,%r2),6
+	vlbb	%v17,0(%r5,%r3),6
+	lcbb	%r1,0(%r5,%r2),6
+	jo	.Llt16_1
+	lcbb	%r4,0(%r5,%r3),6
+	jo	.Llt16_2
+	aghi	%r5,16
+	vfenezbs %v18,%v16,%v17
+	jno	.Lfound
+	j	.Lloop
+
+.Llt16_1:
+	lcbb	%r4,0(%r5,%r3),6 /* Get loaded byte count of s2.  */
+.Llt16_2:
+	clr	%r1,%r4
+	locrh	%r1,%r4		/* Get minimum of bytes loaded in s1/2.  */
+	algfr	%r5,%r1		/* Add smallest loaded bytes to current_len.  */
+	vfenezbs %v18,%v16,%v17	/* Compare not equal with zero search.  */
+	vlgvb	%r4,%v18,7	/* Get not equal index or 16 if all equal.  */
+	clrjl	%r4,%r1,.Lfound /* Jump away if miscompare is within loaded
+				    bytes.  */
+	j	.Lloop
+
+.Lfound:
+	je	.Lend_equal
+	lghi	%r2,1
+	lghi	%r1,-1
+	locgrl	%r2,%r1
+	br	%r14
+.Lend_equal:
+	lghi	%r2,0
+	br	%r14
+END(__strcmp_vx)
+
+# define strcmp __strcmp_c
+# undef libc_hidden_builtin_def
+# define libc_hidden_builtin_def(name) strong_alias(__strcmp_c, __GI_strcmp)
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */
+
+#include <strcmp.S>

sysdeps/s390/multiarch/strcmp.c

@@ -0,0 +1,26 @@
+/* Multiple versions of strcmp.
+   Copyright (C) 2015 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 defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+# include <string.h>
+# include <ifunc-resolve.h>
+
+
+# undef strcmp
+s390_vx_libc_ifunc2 (__strcmp, strcmp)
+#endif

sysdeps/s390/multiarch/wcscmp-c.c

@@ -0,0 +1,32 @@
+/* Default wcscmp implementation for S/390.
+   Copyright (C) 2015 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 defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
+# define WCSCMP  __wcscmp_c
+
+# include <wchar.h>
+extern __typeof (wcscmp) __wcscmp_c;
+# undef weak_alias
+# define weak_alias(name, alias)
+# ifdef SHARED
+#  undef libc_hidden_def
+#  define libc_hidden_def(name)				\
+  __hidden_ver1 (__wcscmp_c, __GI___wcscmp, __wcscmp_c);
+# endif /* SHARED */
+# include <wcsmbs/wcscmp.c>
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */