S390: Optimize strchr and wcschr.

This patch provides optimized versions of strchr and wcschr with the z13
vector instructions.

ChangeLog:

	* sysdeps/s390/multiarch/strchr-c.c: New File.
	* sysdeps/s390/multiarch/strchr-vx.S: Likewise.
	* sysdeps/s390/multiarch/strchr.c: Likewise.
	* sysdeps/s390/multiarch/wcschr-c.c: Likewise.
	* sysdeps/s390/multiarch/wcschr-vx.S: Likewise.
	* sysdeps/s390/multiarch/wcschr.c: Likewise.
	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strchr and
	wcschr functions.
	* sysdeps/s390/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list): Add ifunc test for strchr, wcschr.
	* string/strchr.c (STRCHR): Define and use macro.
	* benchtests/bench-wcschr.c: New File.
	* benchtests/Makefile (wcsmbs-bench): Add wcschr.

ChangeLog

@@ -1,3 +1,19 @@
+2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
+	* sysdeps/s390/multiarch/strchr-c.c: New File.
+	* sysdeps/s390/multiarch/strchr-vx.S: Likewise.
+	* sysdeps/s390/multiarch/strchr.c: Likewise.
+	* sysdeps/s390/multiarch/wcschr-c.c: Likewise.
+	* sysdeps/s390/multiarch/wcschr-vx.S: Likewise.
+	* sysdeps/s390/multiarch/wcschr.c: Likewise.
+	* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strchr and
+	wcschr functions.
+	* sysdeps/s390/multiarch/ifunc-impl-list.c
+	(__libc_ifunc_impl_list): Add ifunc test for strchr, wcschr.
+	* string/strchr.c (STRCHR): Define and use macro.
+	* benchtests/bench-wcschr.c: New File.
+	* benchtests/Makefile (wcsmbs-bench): Add wcschr.
+
 2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
 	* sysdeps/s390/multiarch/strncmp-c.c: New File.

benchtests/Makefile

@@ -37,7 +37,7 @@ string-bench := bcopy bzero memccpy memchr memcmp memcpy memmem memmove \
 		strspn strstr strcpy_chk stpcpy_chk memrchr strsep strtok \
 		strcoll
 wcsmbs-bench := wcslen wcsnlen wcscpy wcpcpy wcsncpy wcpncpy wcscat wcsncat \
-		wcscmp wcsncmp
+		wcscmp wcsncmp wcschr
 string-bench-all := $(string-bench) ${wcsmbs-bench}
 
 # We have to generate locales

benchtests/bench-wcschr.c

@@ -0,0 +1,20 @@
+/* Measure wcschr 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-strchr.c"

string/strchr.c

@@ -25,9 +25,13 @@
 
 #undef strchr
 
+#ifndef STRCHR
+# define STRCHR strchr
+#endif
+
 /* Find the first occurrence of C in S.  */
 char *
-strchr (const char *s, int c_in)
+STRCHR (const char *s, int c_in)
 {
   const unsigned char *char_ptr;
   const unsigned long int *longword_ptr;
@@ -175,7 +179,7 @@ strchr (const char *s, int c_in)
 }
 
 #ifdef weak_alias
-#undef index
+# undef index
 weak_alias (strchr, index)
 #endif
 libc_hidden_builtin_def (strchr)

sysdeps/s390/multiarch/Makefile

@@ -8,7 +8,8 @@ sysdep_routines += strlen strlen-vx strlen-c \
 		   strcat strcat-vx strcat-c \
 		   strncat strncat-vx strncat-c \
 		   strcmp strcmp-vx \
-		   strncmp strncmp-vx strncmp-c
+		   strncmp strncmp-vx strncmp-c \
+		   strchr strchr-vx strchr-c
 endif
 
 ifeq ($(subdir),wcsmbs)
@@ -21,5 +22,6 @@ sysdep_routines += wcslen wcslen-vx wcslen-c \
 		   wcscat wcscat-vx wcscat-c \
 		   wcsncat wcsncat-vx wcsncat-c \
 		   wcscmp wcscmp-vx wcscmp-c \
-		   wcsncmp wcsncmp-vx wcsncmp-c
+		   wcsncmp wcsncmp-vx wcsncmp-c \
+		   wcschr wcschr-vx wcschr-c
 endif

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

@@ -109,6 +109,9 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
   IFUNC_VX_IMPL (strncmp);
   IFUNC_VX_IMPL (wcsncmp);
 
+  IFUNC_VX_IMPL (strchr);
+  IFUNC_VX_IMPL (wcschr);
+
 #endif /* HAVE_S390_VX_ASM_SUPPORT */
 
   return i;

sysdeps/s390/multiarch/strchr-c.c

@@ -0,0 +1,29 @@
+/* Default strchr 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 STRCHR  __strchr_c
+# undef weak_alias
+# ifdef SHARED
+#  undef libc_hidden_builtin_def
+#  define libc_hidden_builtin_def(name)				\
+     __hidden_ver1 (__strchr_c, __GI_strchr, __strchr_c);
+# endif /* SHARED */
+
+# include <string/strchr.c>
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */

sysdeps/s390/multiarch/strchr-vx.S

@@ -0,0 +1,100 @@
+/* Vector optimized 32/64 bit S/390 version of strchr.
+   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
+
+/* char *strchr (const char *s, int c)
+   Locate character in string.
+
+   Register usage:
+   -r1=tmp
+   -r2=s
+   -r3=c
+   -r4=tmp
+   -r5=current_len
+   -v16=part of s
+   -v17=index of unequal
+   -v18=replicated c
+*/
+ENTRY(__strchr_vx)
+	.machine "z13"
+	.machinemode "zarch_nohighgprs"
+
+	vlbb	%v16,0(%r2),6	/* Load s until next 4k-byte boundary.  */
+	lcbb	%r1,0(%r2),6	/* Get bytes to 4k-byte boundary or 16.  */
+
+	lghi	%r5,0		/* current_len = 0.  */
+
+	vlvgb	%v18,%r3,0	/* Generate vector which elements are all c.
+				   If c > 255, c will be truncated.  */
+	vrepb	%v18,%v18,0
+
+	vfeezbs	%v16,%v16,%v18	/* Find element equal with zero search.  */
+	vlgvb	%r4,%v16,7	/* Load byte index of character or zero.  */
+	clrjl	%r4,%r1,.Lfound /* Return if c/zero is in loaded bytes.  */
+
+	/* Align s to 16 byte.  */
+	risbgn	%r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15.  */
+	lghi	%r5,16		/* current_len = 16.  */
+	slr	%r5,%r4		/* Compute bytes to 16bytes boundary.  */
+
+	/* Find c/zero in 16 byte aligned loop */
+.Lloop:
+	vl	%v16,0(%r5,%r2) /* Load s.  */
+	vfeezbs	%v16,%v16,%v18	/* Find element equal with zero search.  */
+	jno	.Lfound		/* Found c/zero (cc=0|1|2).  */
+	vl	%v16,16(%r5,%r2)
+	vfeezbs	%v16,%v16,%v18
+	jno	.Lfound16
+	vl	%v16,32(%r5,%r2)
+	vfeezbs	%v16,%v16,%v18
+	jno	.Lfound32
+	vl	%v16,48(%r5,%r2)
+	vfeezbs	%v16,%v16,%v18
+	jno	.Lfound48
+
+	aghi	%r5,64
+	j	.Lloop		/* No character and no zero -> loop.  */
+
+.Lfound48:
+	la	%r5,16(%r5)	/* Use la since aghi would clobber cc.  */
+.Lfound32:
+	la	%r5,16(%r5)
+.Lfound16:
+	la	%r5,16(%r5)
+.Lfound:
+	je	.Lzero		/* Found zero, but no c before that zero.  */
+
+.Lcharacter:
+	vlgvb	%r4,%v16,7	/* Load byte index of character.  */
+	algr	%r5,%r4
+	la	%r2,0(%r5,%r2)	/* Return pointer to character.  */
+	br	%r14
+
+.Lzero:
+	llgcr	%r3,%r3		/* char c_char = (char) c.  */
+	clije	%r3,0,.Lcharacter /* Found zero and c is zero.  */
+	lghi	%r2,0		/* Return null if character not found.  */
+	br	%r14
+END(__strchr_vx)
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */

sysdeps/s390/multiarch/strchr.c

@@ -0,0 +1,28 @@
+/* Multiple versions of strchr.
+   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>
+
+s390_vx_libc_ifunc2 (__strchr, strchr)
+weak_alias (strchr, index)
+
+#else
+# include <string/strchr.c>
+#endif /* !(defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)) */

sysdeps/s390/multiarch/wcschr-c.c

@@ -0,0 +1,37 @@
+/* Default wcschr 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 WCSCHR  __wcschr_c
+
+# include <wchar.h>
+extern __typeof (__wcschr) __wcschr_c;
+# undef weak_alias
+# define weak_alias(name, alias)
+# ifdef SHARED
+#  undef libc_hidden_def
+#  define libc_hidden_def(name)					\
+  __hidden_ver1 (__wcschr_c, __GI_wcschr, __wcschr_c);		\
+  strong_alias (__wcschr_c, __wcschr_c_1);			\
+  __hidden_ver1 (__wcschr_c_1, __GI___wcschr, __wcschr_c_1);
+#  undef libc_hidden_weak
+#  define libc_hidden_weak(name)
+# endif /* SHARED */
+
+# include <wcsmbs/wcschr.c>
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */