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/* Optimized strpbrk implementation for PowerPC64.
Copyright (C) 2014-2016 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>
/* char [r3] *strpbrk(const char [r4] *s, const char [r5] *accept) */
EALIGN (strpbrk, 4, 0)
CALL_MCOUNT 3
lbz r10,0(r4)
cmpdi cr7,r10,0 /* accept[0] == '\0' ? */
beq cr7,L(nullfound)
/* The idea to speed up the algorithm is to create a lookup table
for fast check if input character should be considered. For ASCII
or ISO-8859-X character sets it has 256 positions. */
/* PPC64 ELF ABI stack is aligned to 16 bytes. */
addi r9,r1,-256
/* Clear the table with 0 values */
li r6, 0
li r7, 4
mtctr r7
mr r8, r9
.align 4
L(zerohash):
std r6, 0(r8)
std r6, 8(r8)
std r6, 16(r8)
std r6, 24(r8)
std r6, 32(r8)
std r6, 40(r8)
std r6, 48(r8)
std r6, 56(r8)
addi r8, r8, 64
bdnz L(zerohash)
/* Initialize the table as:
for (i=0; accept[i]; i++
table[accept[i]]] = 1 */
li r0,1
.align 4
L(init_table):
stbx r0,r9,r10
lbzu r10,1(r4)
cmpdi r0,r10,0
bne cr0,L(init_table)
L(finish_table):
/* set table[0] = 1 */
li r4,1
stb r4,0(r9)
b L(mainloop)
/* Unrool the loop 4 times and check using the table as:
i = 0;
while (1)
{
if (table[input[i++]] == 1)
return (s[i -1] ? s + i - 1: NULL);
if (table[input[i++]] == 1)
return (s[i -1] ? s + i - 1: NULL);
if (table[input[i++]] == 1)
return (s[i -1] ? s + i - 1: NULL);
if (table[input[i++]] == 1)
return (s[i -1] ? s + i - 1: NULL);
} */
.align 4
L(unroll):
lbz r0,1(r3)
lbzx r8,r9,r0
cmpwi cr6,r8,1
beq cr6,L(checkend2)
lbz r10,2(r3)
lbzx r4,r9,r10
cmpwi cr7,r4,1
beq cr7,L(checkend3)
lbz r12,3(r3)
addi r3,r3,4
lbzx r11,r9,r12
cmpwi cr0,r11,1
beq cr0,L(checkend)
L(mainloop):
lbz r12,0(r3)
addi r11,r3,1
addi r5,r3,2
addi r7,r3,3
lbzx r6,r9,r12
cmpwi cr1,r6,1
bne cr1,L(unroll)
cmpdi cr0,r12,0
beq cr0,L(nullfound)
L(end):
blr
.align 4
L(checkend):
cmpdi cr1,r12,0
mr r3,r7
bne cr1,L(end)
L(nullfound):
/* return NULL */
li 3,0
blr
.align 4
L(checkend2):
cmpdi cr7,r0,0
mr r3,r11
beq cr7,L(nullfound)
blr
.align 4
L(checkend3):
cmpdi cr6,r10,0
mr r3,r5
beq cr6,L(nullfound)
blr
END (strpbrk)
libc_hidden_builtin_def (strpbrk)