--- /dev/null
+/* Optimized strtok implementation for PowerPC64.
+
+ 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/>. */
+
+/* Performance gains are grabbed through following techniques:
+
+ > hashing of needle.
+ > hashing avoids scanning of duplicate entries in needle
+ across the string.
+ > 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 is calculated and moved.(strspn)
+ 5. The string is again scanned until end and for every character,
+ its corresponding hash index is compared.(strpbrk)
+ 6. If hash index is set to 1 for the index of string,
+ set it to null and set the saveptr to point to the next char.
+ 7. Otherwise count is incremented and scanning continues
+ until end of string. */
+
+#include <sysdep.h>
+#ifdef USE_AS_STRTOK_R
+# define FUNC_NAME __strtok_r
+#else
+# define FUNC_NAME strtok
+#endif
+
+EALIGN(FUNC_NAME, 4, 0)
+#ifdef USE_AS_STRTOK_R
+ CALL_MCOUNT 3
+ cmpdi cr7, r3, 0 /* Is input null? */
+ bne cr7, L(inputnotNull)
+ ld r3, 0(r5) /* Load from r5 */
+#else
+ CALL_MCOUNT 2
+ addis r5, r2, .LANCHOR0@toc@ha
+ cmpdi cr7, r3, 0 /* Is r3 NULL? */
+ bne cr7, L(inputnotNull)
+ ld r3, .LANCHOR0@toc@l(r5) /* Load from saveptr */
+#endif
+L(inputnotNull):
+ mr r7, r3
+ cmpdi cr7, r3, 0
+ beq cr7, L(returnNULL)
+ lbz r8, 0(r3)
+ cmpdi cr7, r8, 0
+ beq cr7, L(returnNULL)
+
+ addi r9, r1, -256 /* r9 is a hash of 256 bytes */
+
+ /*Iniatliaze hash table with Zeroes */
+ li r6, 0
+ li r8, 4
+ mtctr r8
+ mr r10, r9
+ .align 4
+L(zerohash):
+ std r6, 0(r10)
+ std r6, 8(r10)
+ std r6, 16(r10)
+ std r6, 24(r10)
+ std r6, 32(r10)
+ std r6, 40(r10)
+ std r6, 48(r10)
+ std r6, 56(r10)
+ addi r10, r10, 64
+ bdnz L(zerohash)
+
+
+ lbz r10, 0(r4) /* load r10 with needle (r4) */
+ 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 */
+
+ .align 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):
+ b L(beginScan)
+
+ .align 4 /* align section to 16 byte boundary */
+L(scanUnroll):
+ lbzx r8, r9, r8 /* load r8 with hash value at index */
+ cmpwi cr7, r8, 0 /* check the hash value */
+ beq cr7, L(ret1stIndex) /* we have hit accept needle */
+
+ lbz r8, 1(r7) /* load string[1] into r8 */
+ lbzx r8, r9, r8 /* load r8 with hash value at index */
+ cmpwi cr7, r8, 0 /* check the hash value */
+ beq cr7, L(ret2ndIndex) /* we have hit accept needle */
+
+ lbz r8, 2(r7) /* load string[1] into r8 */
+ lbzx r8, r9, r8 /* load r8 with hash value at index */
+ cmpwi cr7, r8, 0 /* check the hash value */
+ beq cr7, L(ret3rdIndex) /* we have hit accept needle */
+
+ lbz r8, 3(r7) /* load string[1] into r8 */
+ addi r7, r7, 4
+ lbzx r8, r9, r8 /* load r8 with hash value at index */
+ cmpwi cr7, r8, 0 /* check the hash value */
+ beq cr7,L(ret4thIndex) /* we have hit accept needle */
+
+L(beginScan):
+ lbz r8, 0(r7) /* load string[0] into r8 */
+ addi r6, r7, 1
+ addi r11, r7, 2
+ addi r4, r7, 3
+ cmpdi cr7, r8, 0 /* check if its null */
+ bne cr7, L(scanUnroll) /* continue scanning */
+
+L(ret1stIndex):
+ mr r3, r7
+ b L(next)
+L(ret2ndIndex):
+ mr r3, r6
+ b L(next)
+L(ret3rdIndex):
+ mr r3, r11
+ b L(next)
+L(ret4thIndex):
+ mr r3, r4
+L(next):
+ mr r7, r3
+ lbz r8, 0(r7)
+ cmpdi cr7, r8, 0
+ beq cr7, L(returnNULL)
+ li r8, 1
+ li r10, 0 /* load counter = 0 */
+ stbx r8, r9, r10 /* update hash for NULL */
+ b L(mainloop)
+
+L(unroll):
+ lbz r8, 1(r7) /* load string[1] into r8 */
+ lbzx r8, r9, r8 /* load r8 with hash value at index */
+ cmpwi r7, r8, 1 /* check the hash */
+ beq cr7, L(foundat1st) /* we have hit accept needle */
+ lbz r8, 2(r7)
+ lbzx r8, r9, r8
+ cmpwi cr7, r8, 1
+ beq cr7, L(foundat2nd)
+ lbz r8, 3(r7)
+ addi r7, r7, 4
+ lbzx r8, r9, r8
+ cmpwi cr7, r8, 1
+ beq cr7, L(foundat3rd)
+L(mainloop):
+ lbz r8, 0(r7)
+ addi r6, r7, 1
+ addi r11, r7, 2
+ addi r4, r7, 3
+ lbzx r8, r9, r8
+ cmpwi cr7, r8, 1
+ bne cr7, L(unroll) /* continue scanning */
+
+ b L(found)
+L(foundat1st):
+ mr r7, r6
+ b L(found)
+L(foundat2nd):
+ mr r7, r11
+ b L(found)
+L(foundat3rd):
+ mr r7, r4
+L(found):
+ lbz r8, 0(r7)
+ cmpdi cr7, r8, 0
+ beq cr7, L(end)
+ li r10, 0
+ stb r10, 0(r7) /* Terminate string */
+ addi r7, r7, 1 /* Store the pointer to the next char */
+L(end):
+#ifdef USE_AS_STRTOK_R
+ std r7, 0(r5) /* Update saveptr */
+#else
+ std r7, .LANCHOR0@toc@l(r5)
+#endif
+ blr /* done */
+L(returnNULL):
+#ifndef USE_AS_STRTOK_R
+ li r7, 0
+#endif
+ li r3, 0 /* return NULL */
+ b L(end)
+END(FUNC_NAME)
+#ifdef USE_AS_STRTOK_R
+libc_hidden_builtin_def (strtok_r)
+#else
+ .section ".bss"
+ .align 3
+ .set .LANCHOR0,. + 0
+ .type olds, @object
+ .size olds, 8
+olds:
+ .zero 8
+libc_hidden_builtin_def (strtok)
+#endif
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