Multiarch optimization for strspn on POWERPC

Message ID 531DF824.3040302@linux.vnet.ibm.com
State Committed
Delegated to: Adhemerval Zanella Netto
Headers

Commit Message

R Vidya March 10, 2014, 5:36 p.m. UTC
  Hi Adhemerval , fixed it. Please push if OKay.


On Monday 10 March 2014 08:09 PM, Adhemerval Zanella wrote:
> Hi Vidya,
>
> Sorry if I didn't catch it early, but just noted some line are not respecting the 80 column
> requirement from code guidelines, please fix these (example below). Also, I just also noted
> since you are touching 'string/strspn.c' it is worth of cleanup the old C-style (comment
> below). With this change I think it is good to push upstream.
>
>
> On 07-03-2014 07:23, R Vidya wrote:
>> diff --git a/string/strspn.c b/string/strspn.c
>> index 37e8161..557eec5 100644
>> --- a/string/strspn.c
>> +++ b/string/strspn.c
>> @@ -18,11 +18,14 @@
>>   #include <string.h>
>>
>>   #undef strspn
>> +#ifndef STRSPN
>> +#define STRSPN strspn
>> +#endif
>>
>>   /* Return the length of the maximum initial segment
>>      of S which contains only characters in ACCEPT.  */
>>   size_t
>> -strspn (s, accept)
>> +STRSPN (s, accept)
>>        const char *s;
>>        const char *accept;
>>   {
> There is no need on using old K&R style, just convert it to STRSPN (const char *s, const char *accept)
>
>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/Makefile b/sysdeps/powerpc/powerpc64/multiarch/Makefile
>> index a03569e..3e8010c 100644
>> --- a/sysdeps/powerpc/powerpc64/multiarch/Makefile
>> +++ b/sysdeps/powerpc/powerpc64/multiarch/Makefile
>> @@ -14,7 +14,8 @@ sysdep_routines += memcpy-power7 memcpy-a2 memcpy-power6 memcpy-cell \
>>   		   wcsrchr-ppc64 wcscpy-power7 wcscpy-power6 wcscpy-ppc64 \
>>   		   wordcopy-power7 wordcopy-power6 wordcopy-ppc64 \
>>   		   strcpy-power7 strcpy-ppc64 stpcpy-power7 stpcpy-ppc64 \
>> -		   strrchr-power7 strrchr-ppc64 strncat-power7 strncat-ppc64
>> +		   strrchr-power7 strrchr-ppc64 strncat-power7 strncat-ppc64 \
>> +		   strspn-power7 strspn-ppc64
>>
>>   CFLAGS-strncase-power7.c += -mcpu=power7 -funroll-loops
>>   CFLAGS-strncase_l-power7.c += -mcpu=power7 -funroll-loops
>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
>> index 11a3bed..20d7918 100644
>> --- a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
>> +++ b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
>> @@ -254,5 +254,13 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
>>   	      IFUNC_IMPL_ADD (array, i, strncat, 1,
>>   			      __strncat_ppc))
>>
>> +  /* Support sysdeps/powerpc/powerpc64/multiarch/strspn.c.  */
>> +  IFUNC_IMPL (i, name, strspn,
>> +	      IFUNC_IMPL_ADD (array, i, strspn,
>> +			      hwcap & PPC_FEATURE_HAS_VSX,
>> +			      __strspn_power7)
>> +	      IFUNC_IMPL_ADD (array, i, strspn, 1,
>> +			      __strspn_ppc))
>> +
>>     return i;
>>   }
>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S b/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S
>> new file mode 100644
>> index 0000000..889dfee
>> --- /dev/null
>> +++ b/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S
>> @@ -0,0 +1,40 @@
>> +/* Optimized strspn implementation for POWER7.
>> +   Copyright (C) 2014 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/>.  */
>> +
>> +#include <sysdep.h>
>> +
>> +#undef EALIGN
>> +#define EALIGN(name, alignt, words)				\
>> +  .section ".text";						\
>> +  ENTRY_2(__strspn_power7)					\
>> +  .align ALIGNARG(alignt);					\
>> +  EALIGN_W_##words;						\
>> +  BODY_LABEL(__strspn_power7):					\
>> +  cfi_startproc;						\
>> +  LOCALENTRY(__strspn_power7)
>> +
>> +#undef END
>> +#define END(name)						\
>> +  cfi_endproc;							\
>> +  TRACEBACK(__strspn_power7)					\
>> +  END_2(__strspn_power7)
>> +
>> +#undef libc_hidden_builtin_def
>> +#define libc_hidden_builtin_def(name)
>> +
>> +#include <sysdeps/powerpc/powerpc64/power7/strspn.S>
>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c b/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c
>> new file mode 100644
>> index 0000000..d543772
>> --- /dev/null
>> +++ b/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c
>> @@ -0,0 +1,33 @@
>> +/* Copyright (C) 2014 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/>.  */
>> +
>> +#include <string.h>
>> +
>> +#define STRSPN __strspn_ppc
>> +#undef weak_alias
>> +#define weak_alias(name, aliasname) \
>> +  extern __typeof (__strspn_ppc) aliasname \
>> +    __attribute__ ((weak, alias ("__strspn_ppc")));
>> +#if !defined(NOT_IN_libc) && defined(SHARED)
>> +# undef libc_hidden_builtin_def
>> +# define libc_hidden_builtin_def(name) \
>> +  __hidden_ver1(__strspn_ppc, __GI_strspn, __strspn_ppc);
>> +#endif
>> +
>> +extern __typeof (strspn) __strspn_ppc attribute_hidden;
>> +
>> +#include <string/strspn.c>
>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn.c b/sysdeps/powerpc/powerpc64/multiarch/strspn.c
>> new file mode 100644
>> index 0000000..44945f3
>> --- /dev/null
>> +++ b/sysdeps/powerpc/powerpc64/multiarch/strspn.c
>> @@ -0,0 +1,31 @@
>> +/* Multiple versions of strspn. PowerPC64 version.
>> +   Copyright (C) 2014 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 SHARED && !defined NOT_IN_libc
>> +# include <string.h>
>> +# include <shlib-compat.h>
>> +# include "init-arch.h"
>> +
>> +extern __typeof (strspn) __strspn_ppc attribute_hidden;
>> +extern __typeof (strspn) __strspn_power7 attribute_hidden;
>> +
>> +libc_ifunc (strspn,
>> +            (hwcap & PPC_FEATURE_HAS_VSX)
>> +            ? __strspn_power7
>> +            : __strspn_ppc);
>> +#endif
>> diff --git a/sysdeps/powerpc/powerpc64/power7/strspn.S b/sysdeps/powerpc/powerpc64/power7/strspn.S
>> new file mode 100644
>> index 0000000..876e9cc
>> --- /dev/null
>> +++ b/sysdeps/powerpc/powerpc64/power7/strspn.S
>> @@ -0,0 +1,148 @@
>> +/* Optimized strspn implementation for PowerPC64/POWER7.
>> +
>> +   Copyright (C) 2014 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/>.  */
>> +
>> +/* size_t [r3] strspn (const char *string [r3],
>> +                       const char *needleAccept [r4]  */
>> +
>> +/* Performance gains are grabbed through following techniques:
>> +
>> +   > hashing of needle.
>> +   > hashing avoids scanning of duplicate entries in needle across the string.
>> +   > initializing the hash table with Vector instructions by quadword access.
>> +   > unrolling when scanning for character in string across hash table.  */
>> +
>> +/* Algorithm is as below:
>> +   1. A empty hash table/dictionary is created comprising of 256 ascii character set
> Here it is an example of the column limit limit, please break it to fix 80 column.
> Also check for all file, since there are other issues relating to this.
>
>> +   2. When hash entry is found in needle , the hash index is initialized to 1
>> +   3. The string is scanned until end and for every character, its corresponding
>> +      hash index is compared.
>> +   4. initial length of string (count) until first hit of accept needle to be found
>> +      is set to 0
>> +   4. If hash index is set to 1 for the index of string, count is returned.
>> +   5. Otherwise count is incremented and scanning continues until end of string.  */
>> +
>> +#include <sysdep.h>
>> +
>> +#undef strspn
>> +
>> +	.machine  power7
>> +EALIGN(strspn, 4, 0)
>> +	CALL_MCOUNT 2
>> +
>> +	lbz r10, 0(r4)		/* load r10 with needle (r4)  */
>> +	addi r9, r1, -256	/* r9 is a hash of 256 bytes  */
>> +
>> +	li r5, 16		/* set r5 = 16 as offset  */
>> +	li r6, 32		/* set r6 = 32 as offset  */
>> +	li r8, 48		/* set r8 = 48 as offset  */
>> +
>> +/*Iniatliaze hash table with Zeroes in double indexed quadword accesses  */
>> +	xxlxor v0, v0, v0	/* prepare for initializing hash  */
>> +
>> +	stxvd2x v0, r0, r9	/* initialize 1st quadword  */
>> +	stxvd2x v0, r9, r5
>> +	stxvd2x v0, r9, r6
>> +	stxvd2x v0, r9, r8	/* initialize 4th quadword  */
>> +
>> +	addi r11, r9, 64	/* r11 is index to hash  */
>> +
>> +	stxvd2x v0, r0, r11	/* initialize 5th quadword  */
>> +	stxvd2x v0, r11, r5
>> +	stxvd2x v0, r11, r6
>> +	stxvd2x v0, r11, r8	/* initialize 8th quadword  */
>> +
>> +	addi r11, r9, 128	/* r11 is index to hash  */
>> +
>> +	stxvd2x v0, r0, r11	/* initialize 9th quadword  */
>> +	stxvd2x v0, r11, r5
>> +	stxvd2x v0, r11, r6
>> +	stxvd2x v0, r11, r8	/* initialize 12th quadword  */
>> +
>> +	addi r11, r9, 192	/* r11 is index to hash  */
>> +
>> +	stxvd2x v0, r0, r11	/* initialize 13th quadword  */
>> +	stxvd2x v0, r11, r5
>> +	stxvd2x v0, r11, r6
>> +	stxvd2x v0, r11, r8	/* initialize 16th quadword  */
>> +
>> +	li r8, 1		/* r8=1, marker into hash if found in needle  */
>> +
>> +	cmpdi cr7, r10, 0	/* accept needle is NULL  */
>> +	beq cr7, L(skipHashing)	/* if needle is NULL, skip hashing  */
>> +
>> +	.p2align 4		/* align section to 16 byte boundary  */
>> +L(hashing):
>> +	stbx r8, r9, r10	/* update hash with marker for the pivot of the needle  */
>> +	lbzu r10, 1(r4)		/* load needle into r10 and update to next  */
>> +	cmpdi cr7, r10, 0	/* if needle is has reached NULL, continue  */
>> +	bne cr7, L(hashing)	/* loop to hash the needle  */
>> +
>> +L(skipHashing):
>> +	li r10, 0		/* load counter = 0  */
>> +	b L(beginScan)
>> +
>> +	.p2align 4		/* align section to 16 byte boundary  */
>> +L(scanUnroll):
>> +	lbzx r8, r9, r8		/* load r8 with hash value at index  */
>> +	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
>> +	beq cr7, L(ret1stIndex)	/* we have hit accept needle, return the count  */
>> +
>> +	lbz r8, 1(r3)		/* load string[1] into r8  */
>> +	addi r10, r10, 4	/* increment counter  */
>> +	lbzx r8, r9, r8		/* load r8 with hash value at index  */
>> +	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
>> +	beq cr7, L(ret2ndIndex)	/* we have hit accept needle, return the count  */
>> +
>> +	lbz r8, 2(r3)		/* load string[2] into r8  */
>> +	lbzx r8, r9, r8		/* load r8 with hash value at index  */
>> +	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
>> +	beq cr7, L(ret3rdIndex)	/* we have hit accept needle, return the count  */
>> +
>> +	lbz r8, 3(r3)		/* load string[3] into r8  */
>> +	lbzx r8, r9, r8		/* load r8 with hash value at index  */
>> +	addi r3, r3, 4		/* unroll factor , increment string by 4  */
>> +	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
>> +	beq cr7,L(ret4thIndex)	/* we have hit accept needle, return the count  */
>> +
>> +L(beginScan):
>> +	lbz r8, 0(r3)		/* load string[0] into r8  */
>> +	addi r6, r10, 1		/* place holder for counter + 1  */
>> +	addi r5, r10, 2		/* place holder for counter + 2  */
>> +	addi r4, r10, 3		/* place holder for counter + 3  */
>> +	cmpdi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
>> +	bne cr7, L(scanUnroll)	/* continue scanning  */
>> +
>> +L(ret1stIndex):
>> +	mr r3, r10		/* update r3 for return  */
>> +	blr			/* return  */
>> +
>> +L(ret2ndIndex):
>> +	mr r3, r6		/* update r3 for return  */
>> +	blr			/* return  */
>> +
>> +L(ret3rdIndex):
>> +	mr r3, r5		/* update r3 for return  */
>> +	blr			/* return  */
>> +
>> +L(ret4thIndex):
>> +	mr r3, r4		/* update r3 for return  */
>> +	blr			/* done  */
>> +
>> +END(strspn)
>> +libc_hidden_builtin_def (strspn)
  

Comments

Adhemerval Zanella Netto March 11, 2014, 2:22 p.m. UTC | #1
Hi Vidya,

Pushed as e65caf1f1df4ecc122da3d30689ee2e8e2bd354f , thanks

On 10-03-2014 14:36, R Vidya wrote:
> Hi Adhemerval , fixed it. Please push if OKay.
>
>
> On Monday 10 March 2014 08:09 PM, Adhemerval Zanella wrote:
>> Hi Vidya,
>>
>> Sorry if I didn't catch it early, but just noted some line are not respecting the 80 column
>> requirement from code guidelines, please fix these (example below). Also, I just also noted
>> since you are touching 'string/strspn.c' it is worth of cleanup the old C-style (comment
>> below). With this change I think it is good to push upstream.
>>
>>
>> On 07-03-2014 07:23, R Vidya wrote:
>>> diff --git a/string/strspn.c b/string/strspn.c
>>> index 37e8161..557eec5 100644
>>> --- a/string/strspn.c
>>> +++ b/string/strspn.c
>>> @@ -18,11 +18,14 @@
>>>   #include <string.h>
>>>
>>>   #undef strspn
>>> +#ifndef STRSPN
>>> +#define STRSPN strspn
>>> +#endif
>>>
>>>   /* Return the length of the maximum initial segment
>>>      of S which contains only characters in ACCEPT.  */
>>>   size_t
>>> -strspn (s, accept)
>>> +STRSPN (s, accept)
>>>        const char *s;
>>>        const char *accept;
>>>   {
>> There is no need on using old K&R style, just convert it to STRSPN (const char *s, const char *accept)
>>
>>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/Makefile b/sysdeps/powerpc/powerpc64/multiarch/Makefile
>>> index a03569e..3e8010c 100644
>>> --- a/sysdeps/powerpc/powerpc64/multiarch/Makefile
>>> +++ b/sysdeps/powerpc/powerpc64/multiarch/Makefile
>>> @@ -14,7 +14,8 @@ sysdep_routines += memcpy-power7 memcpy-a2 memcpy-power6 memcpy-cell \
>>>              wcsrchr-ppc64 wcscpy-power7 wcscpy-power6 wcscpy-ppc64 \
>>>              wordcopy-power7 wordcopy-power6 wordcopy-ppc64 \
>>>              strcpy-power7 strcpy-ppc64 stpcpy-power7 stpcpy-ppc64 \
>>> -           strrchr-power7 strrchr-ppc64 strncat-power7 strncat-ppc64
>>> +           strrchr-power7 strrchr-ppc64 strncat-power7 strncat-ppc64 \
>>> +           strspn-power7 strspn-ppc64
>>>
>>>   CFLAGS-strncase-power7.c += -mcpu=power7 -funroll-loops
>>>   CFLAGS-strncase_l-power7.c += -mcpu=power7 -funroll-loops
>>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
>>> index 11a3bed..20d7918 100644
>>> --- a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
>>> +++ b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
>>> @@ -254,5 +254,13 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
>>>             IFUNC_IMPL_ADD (array, i, strncat, 1,
>>>                     __strncat_ppc))
>>>
>>> +  /* Support sysdeps/powerpc/powerpc64/multiarch/strspn.c.  */
>>> +  IFUNC_IMPL (i, name, strspn,
>>> +          IFUNC_IMPL_ADD (array, i, strspn,
>>> +                  hwcap & PPC_FEATURE_HAS_VSX,
>>> +                  __strspn_power7)
>>> +          IFUNC_IMPL_ADD (array, i, strspn, 1,
>>> +                  __strspn_ppc))
>>> +
>>>     return i;
>>>   }
>>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S b/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S
>>> new file mode 100644
>>> index 0000000..889dfee
>>> --- /dev/null
>>> +++ b/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S
>>> @@ -0,0 +1,40 @@
>>> +/* Optimized strspn implementation for POWER7.
>>> +   Copyright (C) 2014 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/>.  */
>>> +
>>> +#include <sysdep.h>
>>> +
>>> +#undef EALIGN
>>> +#define EALIGN(name, alignt, words)                \
>>> +  .section ".text";                        \
>>> +  ENTRY_2(__strspn_power7)                    \
>>> +  .align ALIGNARG(alignt);                    \
>>> +  EALIGN_W_##words;                        \
>>> +  BODY_LABEL(__strspn_power7):                    \
>>> +  cfi_startproc;                        \
>>> +  LOCALENTRY(__strspn_power7)
>>> +
>>> +#undef END
>>> +#define END(name)                        \
>>> +  cfi_endproc;                            \
>>> +  TRACEBACK(__strspn_power7)                    \
>>> +  END_2(__strspn_power7)
>>> +
>>> +#undef libc_hidden_builtin_def
>>> +#define libc_hidden_builtin_def(name)
>>> +
>>> +#include <sysdeps/powerpc/powerpc64/power7/strspn.S>
>>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c b/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c
>>> new file mode 100644
>>> index 0000000..d543772
>>> --- /dev/null
>>> +++ b/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c
>>> @@ -0,0 +1,33 @@
>>> +/* Copyright (C) 2014 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/>.  */
>>> +
>>> +#include <string.h>
>>> +
>>> +#define STRSPN __strspn_ppc
>>> +#undef weak_alias
>>> +#define weak_alias(name, aliasname) \
>>> +  extern __typeof (__strspn_ppc) aliasname \
>>> +    __attribute__ ((weak, alias ("__strspn_ppc")));
>>> +#if !defined(NOT_IN_libc) && defined(SHARED)
>>> +# undef libc_hidden_builtin_def
>>> +# define libc_hidden_builtin_def(name) \
>>> +  __hidden_ver1(__strspn_ppc, __GI_strspn, __strspn_ppc);
>>> +#endif
>>> +
>>> +extern __typeof (strspn) __strspn_ppc attribute_hidden;
>>> +
>>> +#include <string/strspn.c>
>>> diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn.c b/sysdeps/powerpc/powerpc64/multiarch/strspn.c
>>> new file mode 100644
>>> index 0000000..44945f3
>>> --- /dev/null
>>> +++ b/sysdeps/powerpc/powerpc64/multiarch/strspn.c
>>> @@ -0,0 +1,31 @@
>>> +/* Multiple versions of strspn. PowerPC64 version.
>>> +   Copyright (C) 2014 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 SHARED && !defined NOT_IN_libc
>>> +# include <string.h>
>>> +# include <shlib-compat.h>
>>> +# include "init-arch.h"
>>> +
>>> +extern __typeof (strspn) __strspn_ppc attribute_hidden;
>>> +extern __typeof (strspn) __strspn_power7 attribute_hidden;
>>> +
>>> +libc_ifunc (strspn,
>>> +            (hwcap & PPC_FEATURE_HAS_VSX)
>>> +            ? __strspn_power7
>>> +            : __strspn_ppc);
>>> +#endif
>>> diff --git a/sysdeps/powerpc/powerpc64/power7/strspn.S b/sysdeps/powerpc/powerpc64/power7/strspn.S
>>> new file mode 100644
>>> index 0000000..876e9cc
>>> --- /dev/null
>>> +++ b/sysdeps/powerpc/powerpc64/power7/strspn.S
>>> @@ -0,0 +1,148 @@
>>> +/* Optimized strspn implementation for PowerPC64/POWER7.
>>> +
>>> +   Copyright (C) 2014 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/>.  */
>>> +
>>> +/* size_t [r3] strspn (const char *string [r3],
>>> +                       const char *needleAccept [r4]  */
>>> +
>>> +/* Performance gains are grabbed through following techniques:
>>> +
>>> +   > hashing of needle.
>>> +   > hashing avoids scanning of duplicate entries in needle across the string.
>>> +   > initializing the hash table with Vector instructions by quadword access.
>>> +   > unrolling when scanning for character in string across hash table.  */
>>> +
>>> +/* Algorithm is as below:
>>> +   1. A empty hash table/dictionary is created comprising of 256 ascii character set
>> Here it is an example of the column limit limit, please break it to fix 80 column.
>> Also check for all file, since there are other issues relating to this.
>>
>>> +   2. When hash entry is found in needle , the hash index is initialized to 1
>>> +   3. The string is scanned until end and for every character, its corresponding
>>> +      hash index is compared.
>>> +   4. initial length of string (count) until first hit of accept needle to be found
>>> +      is set to 0
>>> +   4. If hash index is set to 1 for the index of string, count is returned.
>>> +   5. Otherwise count is incremented and scanning continues until end of string.  */
>>> +
>>> +#include <sysdep.h>
>>> +
>>> +#undef strspn
>>> +
>>> +    .machine  power7
>>> +EALIGN(strspn, 4, 0)
>>> +    CALL_MCOUNT 2
>>> +
>>> +    lbz r10, 0(r4)        /* load r10 with needle (r4)  */
>>> +    addi r9, r1, -256    /* r9 is a hash of 256 bytes  */
>>> +
>>> +    li r5, 16        /* set r5 = 16 as offset  */
>>> +    li r6, 32        /* set r6 = 32 as offset  */
>>> +    li r8, 48        /* set r8 = 48 as offset  */
>>> +
>>> +/*Iniatliaze hash table with Zeroes in double indexed quadword accesses  */
>>> +    xxlxor v0, v0, v0    /* prepare for initializing hash  */
>>> +
>>> +    stxvd2x v0, r0, r9    /* initialize 1st quadword  */
>>> +    stxvd2x v0, r9, r5
>>> +    stxvd2x v0, r9, r6
>>> +    stxvd2x v0, r9, r8    /* initialize 4th quadword  */
>>> +
>>> +    addi r11, r9, 64    /* r11 is index to hash  */
>>> +
>>> +    stxvd2x v0, r0, r11    /* initialize 5th quadword  */
>>> +    stxvd2x v0, r11, r5
>>> +    stxvd2x v0, r11, r6
>>> +    stxvd2x v0, r11, r8    /* initialize 8th quadword  */
>>> +
>>> +    addi r11, r9, 128    /* r11 is index to hash  */
>>> +
>>> +    stxvd2x v0, r0, r11    /* initialize 9th quadword  */
>>> +    stxvd2x v0, r11, r5
>>> +    stxvd2x v0, r11, r6
>>> +    stxvd2x v0, r11, r8    /* initialize 12th quadword  */
>>> +
>>> +    addi r11, r9, 192    /* r11 is index to hash  */
>>> +
>>> +    stxvd2x v0, r0, r11    /* initialize 13th quadword  */
>>> +    stxvd2x v0, r11, r5
>>> +    stxvd2x v0, r11, r6
>>> +    stxvd2x v0, r11, r8    /* initialize 16th quadword  */
>>> +
>>> +    li r8, 1        /* r8=1, marker into hash if found in needle  */
>>> +
>>> +    cmpdi cr7, r10, 0    /* accept needle is NULL  */
>>> +    beq cr7, L(skipHashing)    /* if needle is NULL, skip hashing  */
>>> +
>>> +    .p2align 4        /* align section to 16 byte boundary  */
>>> +L(hashing):
>>> +    stbx r8, r9, r10    /* update hash with marker for the pivot of the needle  */
>>> +    lbzu r10, 1(r4)        /* load needle into r10 and update to next  */
>>> +    cmpdi cr7, r10, 0    /* if needle is has reached NULL, continue  */
>>> +    bne cr7, L(hashing)    /* loop to hash the needle  */
>>> +
>>> +L(skipHashing):
>>> +    li r10, 0        /* load counter = 0  */
>>> +    b L(beginScan)
>>> +
>>> +    .p2align 4        /* align section to 16 byte boundary  */
>>> +L(scanUnroll):
>>> +    lbzx r8, r9, r8        /* load r8 with hash value at index  */
>>> +    cmpwi cr7, r8, 0    /* if we hit marker in hash, we have found accept needle  */
>>> +    beq cr7, L(ret1stIndex)    /* we have hit accept needle, return the count  */
>>> +
>>> +    lbz r8, 1(r3)        /* load string[1] into r8  */
>>> +    addi r10, r10, 4    /* increment counter  */
>>> +    lbzx r8, r9, r8        /* load r8 with hash value at index  */
>>> +    cmpwi cr7, r8, 0    /* if we hit marker in hash, we have found accept needle  */
>>> +    beq cr7, L(ret2ndIndex)    /* we have hit accept needle, return the count  */
>>> +
>>> +    lbz r8, 2(r3)        /* load string[2] into r8  */
>>> +    lbzx r8, r9, r8        /* load r8 with hash value at index  */
>>> +    cmpwi cr7, r8, 0    /* if we hit marker in hash, we have found accept needle  */
>>> +    beq cr7, L(ret3rdIndex)    /* we have hit accept needle, return the count  */
>>> +
>>> +    lbz r8, 3(r3)        /* load string[3] into r8  */
>>> +    lbzx r8, r9, r8        /* load r8 with hash value at index  */
>>> +    addi r3, r3, 4        /* unroll factor , increment string by 4  */
>>> +    cmpwi cr7, r8, 0    /* if we hit marker in hash, we have found accept needle  */
>>> +    beq cr7,L(ret4thIndex)    /* we have hit accept needle, return the count  */
>>> +
>>> +L(beginScan):
>>> +    lbz r8, 0(r3)        /* load string[0] into r8  */
>>> +    addi r6, r10, 1        /* place holder for counter + 1  */
>>> +    addi r5, r10, 2        /* place holder for counter + 2  */
>>> +    addi r4, r10, 3        /* place holder for counter + 3  */
>>> +    cmpdi cr7, r8, 0    /* if we hit marker in hash, we have found accept needle  */
>>> +    bne cr7, L(scanUnroll)    /* continue scanning  */
>>> +
>>> +L(ret1stIndex):
>>> +    mr r3, r10        /* update r3 for return  */
>>> +    blr            /* return  */
>>> +
>>> +L(ret2ndIndex):
>>> +    mr r3, r6        /* update r3 for return  */
>>> +    blr            /* return  */
>>> +
>>> +L(ret3rdIndex):
>>> +    mr r3, r5        /* update r3 for return  */
>>> +    blr            /* return  */
>>> +
>>> +L(ret4thIndex):
>>> +    mr r3, r4        /* update r3 for return  */
>>> +    blr            /* done  */
>>> +
>>> +END(strspn)
>>> +libc_hidden_builtin_def (strspn)
>
  

Patch

>From 49b84f6296408669abd6d73beb5fe7e2c37fcdba Mon Sep 17 00:00:00 2001
From: Vidya Ranganathan <vidya@linux.vnet.ibm.com>
Date: Mon, 10 Mar 2014 12:20:36 -0400
Subject: [PATCH] Multiarch optimization for strspn() on PowerPC. I have
 attached the benchtest output to show the performance improvement.

The optimization is achieved by following techniques:
   > hashing of needle.
   > hashing avoids scanning of duplicate entries in needle across the string.
   > initializing the hash table with Vector instructions (VSX) by quadword access.
   > unrolling when scanning for character in string across hash table.

ChangeLog:
2014-03-04  Vidya Ranganathan  <vidya@linux.vnet.ibm.com>

	* sysdeps/powerpc/powerpc64/power7/strspn.S: New file: Optimization.
	* sysdeps/powerpc/powerpc64/multiarch/strspn.c: New file:
	multiarch strspn for PPC64.
	* sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c: New file
	* sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S: New file
	* sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c:
	(__libc_ifunc_impl_list): Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/Makefile: Add strspn
	multiarch optimizations
	* string/strspn.c (strspn): Using macro to redefine symbol name.

Signed-off-by: Vidya Ranganathan <vidya@linux.vnet.ibm.com>
---
 string/strspn.c                                    |   7 +-
 sysdeps/powerpc/powerpc64/multiarch/Makefile       |   3 +-
 .../powerpc/powerpc64/multiarch/ifunc-impl-list.c  |   8 ++
 .../powerpc/powerpc64/multiarch/strspn-power7.S    |  40 ++++++
 sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c |  33 +++++
 sysdeps/powerpc/powerpc64/multiarch/strspn.c       |  31 +++++
 sysdeps/powerpc/powerpc64/power7/strspn.S          | 155 +++++++++++++++++++++
 7 files changed, 273 insertions(+), 4 deletions(-)
 create mode 100644 sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S
 create mode 100644 sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c
 create mode 100644 sysdeps/powerpc/powerpc64/multiarch/strspn.c
 create mode 100644 sysdeps/powerpc/powerpc64/power7/strspn.S

diff --git a/string/strspn.c b/string/strspn.c
index 37e8161..c2d6364 100644
--- a/string/strspn.c
+++ b/string/strspn.c
@@ -18,13 +18,14 @@ 
 #include <string.h>
 
 #undef strspn
+#ifndef STRSPN
+#define STRSPN strspn
+#endif
 
 /* Return the length of the maximum initial segment
    of S which contains only characters in ACCEPT.  */
 size_t
-strspn (s, accept)
-     const char *s;
-     const char *accept;
+STRSPN (const char *s, const char *accept)
 {
   const char *p;
   const char *a;
diff --git a/sysdeps/powerpc/powerpc64/multiarch/Makefile b/sysdeps/powerpc/powerpc64/multiarch/Makefile
index a03569e..3e8010c 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/Makefile
+++ b/sysdeps/powerpc/powerpc64/multiarch/Makefile
@@ -14,7 +14,8 @@  sysdep_routines += memcpy-power7 memcpy-a2 memcpy-power6 memcpy-cell \
 		   wcsrchr-ppc64 wcscpy-power7 wcscpy-power6 wcscpy-ppc64 \
 		   wordcopy-power7 wordcopy-power6 wordcopy-ppc64 \
 		   strcpy-power7 strcpy-ppc64 stpcpy-power7 stpcpy-ppc64 \
-		   strrchr-power7 strrchr-ppc64 strncat-power7 strncat-ppc64
+		   strrchr-power7 strrchr-ppc64 strncat-power7 strncat-ppc64 \
+		   strspn-power7 strspn-ppc64
 
 CFLAGS-strncase-power7.c += -mcpu=power7 -funroll-loops
 CFLAGS-strncase_l-power7.c += -mcpu=power7 -funroll-loops
diff --git a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
index 11a3bed..20d7918 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
@@ -254,5 +254,13 @@  __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 	      IFUNC_IMPL_ADD (array, i, strncat, 1,
 			      __strncat_ppc))
 
+  /* Support sysdeps/powerpc/powerpc64/multiarch/strspn.c.  */
+  IFUNC_IMPL (i, name, strspn,
+	      IFUNC_IMPL_ADD (array, i, strspn,
+			      hwcap & PPC_FEATURE_HAS_VSX,
+			      __strspn_power7)
+	      IFUNC_IMPL_ADD (array, i, strspn, 1,
+			      __strspn_ppc))
+
   return i;
 }
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S b/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S
new file mode 100644
index 0000000..889dfee
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/multiarch/strspn-power7.S
@@ -0,0 +1,40 @@ 
+/* Optimized strspn implementation for POWER7.
+   Copyright (C) 2014 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/>.  */
+
+#include <sysdep.h>
+
+#undef EALIGN
+#define EALIGN(name, alignt, words)				\
+  .section ".text";						\
+  ENTRY_2(__strspn_power7)					\
+  .align ALIGNARG(alignt);					\
+  EALIGN_W_##words;						\
+  BODY_LABEL(__strspn_power7):					\
+  cfi_startproc;						\
+  LOCALENTRY(__strspn_power7)
+
+#undef END
+#define END(name)						\
+  cfi_endproc;							\
+  TRACEBACK(__strspn_power7)					\
+  END_2(__strspn_power7)
+
+#undef libc_hidden_builtin_def
+#define libc_hidden_builtin_def(name)
+
+#include <sysdeps/powerpc/powerpc64/power7/strspn.S>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c b/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c
new file mode 100644
index 0000000..d543772
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/multiarch/strspn-ppc64.c
@@ -0,0 +1,33 @@ 
+/* Copyright (C) 2014 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/>.  */
+
+#include <string.h>
+
+#define STRSPN __strspn_ppc
+#undef weak_alias
+#define weak_alias(name, aliasname) \
+  extern __typeof (__strspn_ppc) aliasname \
+    __attribute__ ((weak, alias ("__strspn_ppc")));
+#if !defined(NOT_IN_libc) && defined(SHARED)
+# undef libc_hidden_builtin_def
+# define libc_hidden_builtin_def(name) \
+  __hidden_ver1(__strspn_ppc, __GI_strspn, __strspn_ppc);
+#endif
+
+extern __typeof (strspn) __strspn_ppc attribute_hidden;
+
+#include <string/strspn.c>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strspn.c b/sysdeps/powerpc/powerpc64/multiarch/strspn.c
new file mode 100644
index 0000000..44945f3
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/multiarch/strspn.c
@@ -0,0 +1,31 @@ 
+/* Multiple versions of strspn. PowerPC64 version.
+   Copyright (C) 2014 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 SHARED && !defined NOT_IN_libc
+# include <string.h>
+# include <shlib-compat.h>
+# include "init-arch.h"
+
+extern __typeof (strspn) __strspn_ppc attribute_hidden;
+extern __typeof (strspn) __strspn_power7 attribute_hidden;
+
+libc_ifunc (strspn,
+            (hwcap & PPC_FEATURE_HAS_VSX)
+            ? __strspn_power7
+            : __strspn_ppc);
+#endif
diff --git a/sysdeps/powerpc/powerpc64/power7/strspn.S b/sysdeps/powerpc/powerpc64/power7/strspn.S
new file mode 100644
index 0000000..6033b02
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/power7/strspn.S
@@ -0,0 +1,155 @@ 
+/* Optimized strspn implementation for PowerPC64/POWER7.
+
+   Copyright (C) 2014 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/>.  */
+
+/* size_t [r3] strspn (const char *string [r3],
+                       const char *needleAccept [r4]  */
+
+/* Performance gains are grabbed through following techniques:
+
+   > hashing of needle.
+   > hashing avoids scanning of duplicate entries in needle
+     across the string.
+   > initializing the hash table with Vector instructions
+     by quadword access.
+   > unrolling when scanning for character in string
+     across hash table.  */
+
+/* Algorithm is as below:
+   1. A empty hash table/dictionary is created comprising of
+      256 ascii character set
+   2. When hash entry is found in needle , the hash index
+      is initialized to 1
+   3. The string is scanned until end and for every character,
+      its corresponding hash index is compared.
+   4. initial length of string (count) until first hit of
+      accept needle to be found is set to 0
+   4. If hash index is set to 1 for the index of string,
+      count is returned.
+   5. Otherwise count is incremented and scanning continues
+      until end of string.  */
+
+#include <sysdep.h>
+
+#undef strspn
+
+	.machine  power7
+EALIGN(strspn, 4, 0)
+	CALL_MCOUNT 2
+
+	lbz r10, 0(r4)		/* load r10 with needle (r4)  */
+	addi r9, r1, -256	/* r9 is a hash of 256 bytes  */
+
+	li r5, 16		/* set r5 = 16 as offset  */
+	li r6, 32		/* set r6 = 32 as offset  */
+	li r8, 48		/* set r8 = 48 as offset  */
+
+/*Iniatliaze hash table with Zeroes in double indexed quadword accesses  */
+	xxlxor v0, v0, v0	/* prepare for initializing hash  */
+
+	stxvd2x v0, r0, r9	/* initialize 1st quadword  */
+	stxvd2x v0, r9, r5
+	stxvd2x v0, r9, r6
+	stxvd2x v0, r9, r8	/* initialize 4th quadword  */
+
+	addi r11, r9, 64	/* r11 is index to hash  */
+
+	stxvd2x v0, r0, r11	/* initialize 5th quadword  */
+	stxvd2x v0, r11, r5
+	stxvd2x v0, r11, r6
+	stxvd2x v0, r11, r8	/* initialize 8th quadword  */
+
+	addi r11, r9, 128	/* r11 is index to hash  */
+
+	stxvd2x v0, r0, r11	/* initialize 9th quadword  */
+	stxvd2x v0, r11, r5
+	stxvd2x v0, r11, r6
+	stxvd2x v0, r11, r8	/* initialize 12th quadword  */
+
+	addi r11, r9, 192	/* r11 is index to hash  */
+
+	stxvd2x v0, r0, r11	/* initialize 13th quadword  */
+	stxvd2x v0, r11, r5
+	stxvd2x v0, r11, r6
+	stxvd2x v0, r11, r8	/* initialize 16th quadword  */
+
+	li r8, 1		/* r8=1, marker into hash if found in needle  */
+
+	cmpdi cr7, r10, 0	/* accept needle is NULL  */
+	beq cr7, L(skipHashing)	/* if needle is NULL, skip hashing  */
+
+	.p2align 4		/* align section to 16 byte boundary  */
+L(hashing):
+	stbx r8, r9, r10	/* update hash with marker for the pivot of the needle  */
+	lbzu r10, 1(r4)		/* load needle into r10 and update to next  */
+	cmpdi cr7, r10, 0	/* if needle is has reached NULL, continue  */
+	bne cr7, L(hashing)	/* loop to hash the needle  */
+
+L(skipHashing):
+	li r10, 0		/* load counter = 0  */
+	b L(beginScan)
+
+	.p2align 4		/* align section to 16 byte boundary  */
+L(scanUnroll):
+	lbzx r8, r9, r8		/* load r8 with hash value at index  */
+	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
+	beq cr7, L(ret1stIndex)	/* we have hit accept needle, return the count  */
+
+	lbz r8, 1(r3)		/* load string[1] into r8  */
+	addi r10, r10, 4	/* increment counter  */
+	lbzx r8, r9, r8		/* load r8 with hash value at index  */
+	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
+	beq cr7, L(ret2ndIndex)	/* we have hit accept needle, return the count  */
+
+	lbz r8, 2(r3)		/* load string[2] into r8  */
+	lbzx r8, r9, r8		/* load r8 with hash value at index  */
+	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
+	beq cr7, L(ret3rdIndex)	/* we have hit accept needle, return the count  */
+
+	lbz r8, 3(r3)		/* load string[3] into r8  */
+	lbzx r8, r9, r8		/* load r8 with hash value at index  */
+	addi r3, r3, 4		/* unroll factor , increment string by 4  */
+	cmpwi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
+	beq cr7,L(ret4thIndex)	/* we have hit accept needle, return the count  */
+
+L(beginScan):
+	lbz r8, 0(r3)		/* load string[0] into r8  */
+	addi r6, r10, 1		/* place holder for counter + 1  */
+	addi r5, r10, 2		/* place holder for counter + 2  */
+	addi r4, r10, 3		/* place holder for counter + 3  */
+	cmpdi cr7, r8, 0	/* if we hit marker in hash, we have found accept needle  */
+	bne cr7, L(scanUnroll)	/* continue scanning  */
+
+L(ret1stIndex):
+	mr r3, r10		/* update r3 for return  */
+	blr			/* return  */
+
+L(ret2ndIndex):
+	mr r3, r6		/* update r3 for return  */
+	blr			/* return  */
+
+L(ret3rdIndex):
+	mr r3, r5		/* update r3 for return  */
+	blr			/* return  */
+
+L(ret4thIndex):
+	mr r3, r4		/* update r3 for return  */
+	blr			/* done  */
+
+END(strspn)
+libc_hidden_builtin_def (strspn)
-- 
1.8.3.1