/*
* String handling functions for PowerPC.
*
* Copyright (C) 1996 Paul Mackerras.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <asm/processor.h>
#include <asm/errno.h>
#include <asm/ppc_asm.h>
_GLOBAL(strcpy)
addi r5,r3,-1
addi r4,r4,-1
1: lbzu r0,1(r4)
cmpwi 0,r0,0
stbu r0,1(r5)
bne 1b
blr
_GLOBAL(strncpy)
cmpwi 0,r5,0
beqlr
mtctr r5
addi r6,r3,-1
addi r4,r4,-1
1: lbzu r0,1(r4)
cmpwi 0,r0,0
stbu r0,1(r6)
bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */
blr
_GLOBAL(strcat)
addi r5,r3,-1
addi r4,r4,-1
1: lbzu r0,1(r5)
cmpwi 0,r0,0
bne 1b
addi r5,r5,-1
1: lbzu r0,1(r4)
cmpwi 0,r0,0
stbu r0,1(r5)
bne 1b
blr
_GLOBAL(strcmp)
addi r5,r3,-1
addi r4,r4,-1
1: lbzu r3,1(r5)
cmpwi 1,r3,0
lbzu r0,1(r4)
subf. r3,r0,r3
beqlr 1
beq 1b
blr
_GLOBAL(strlen)
addi r4,r3,-1
1: lbzu r0,1(r4)
cmpwi 0,r0,0
bne 1b
subf r3,r3,r4
blr
_GLOBAL(memset)
neg r0,r3
rlwimi r4,r4,8,16,23
andi. r0,r0,7 /* # bytes to be 8-byte aligned */
rlwimi r4,r4,16,0,15
cmplw cr1,r5,r0 /* do we get that far? */
rldimi r4,r4,32,0
mtcrf 1,r0
mr r6,r3
blt cr1,8f
beq+ 3f /* if already 8-byte aligned */
subf r5,r0,r5
bf 31,1f
stb r4,0(r6)
addi r6,r6,1
1: bf 30,2f
sth r4,0(r6)
addi r6,r6,2
2: bf 29,3f
stw r4,0(r6)
addi r6,r6,4
3: srdi. r0,r5,6
clrldi r5,r5,58
mtctr r0
beq 5f
4: std r4,0(r6)
std r4,8(r6)
std r4,16(r6)
std r4,24(r6)
std r4,32(r6)
std r4,40(r6)
std r4,48(r6)
std r4,56(r6)
addi r6,r6,64
bdnz 4b
5: srwi. r0,r5,3
clrlwi r5,r5,29
mtcrf 1,r0
beq 8f
bf 29,6f
std r4,0(r6)
std r4,8(r6)
std r4,16(r6)
std r4,24(r6)
addi r6,r6,32
6: bf 30,7f
std r4,0(r6)
std r4,8(r6)
addi r6,r6,16
7: bf 31,8f
std r4,0(r6)
addi r6,r6,8
8: cmpwi r5,0
mtcrf 1,r5
beqlr+
bf 29,9f
stw r4,0(r6)
addi r6,r6,4
9: bf 30,10f
sth r4,0(r6)
addi r6,r6,2
10: bflr 31
stb r4,0(r6)
blr
_GLOBAL(memmove)
cmplw 0,r3,r4
bgt .backwards_memcpy
b .memcpy
_GLOBAL(backwards_memcpy)
rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */
add r6,r3,r5
add r4,r4,r5
beq 2f
andi. r0,r6,3
mtctr r7
bne 5f
1: lwz r7,-4(r4)
lwzu r8,-8(r4)
stw r7,-4(r6)
stwu r8,-8(r6)
bdnz 1b
andi. r5,r5,7
2: cmplwi 0,r5,4
blt 3f
lwzu r0,-4(r4)
subi r5,r5,4
stwu r0,-4(r6)
3: cmpwi 0,r5,0
beqlr
mtctr r5
4: lbzu r0,-1(r4)
stbu r0,-1(r6)
bdnz 4b
blr
5: mtctr r0
6: lbzu r7,-1(r4)
stbu r7,-1(r6)
bdnz 6b
subf r5,r0,r5
rlwinm. r7,r5,32-3,3,31
beq 2b
mtctr r7
b 1b
_GLOBAL(memcmp)
cmpwi 0,r5,0
ble- 2f
mtctr r5
addi r6,r3,-1
addi r4,r4,-1
1: lbzu r3,1(r6)
lbzu r0,1(r4)
subf. r3,r0,r3
bdnzt 2,1b
blr
2: li r3,0
blr
_GLOBAL(memchr)
cmpwi 0,r5,0
ble- 2f
mtctr r5
addi r3,r3,-1
1: lbzu r0,1(r3)
cmpw 0,r0,r4
bdnzf 2,1b
beqlr
2: li r3,0
blr
_GLOBAL(__clear_user)
addi r6,r3,-4
li r3,0
li r5,0
cmplwi 0,r4,4
blt 7f
/* clear a single word */
11: stwu r5,4(r6)
beqlr
/* clear word sized chunks */
andi. r0,r6,3
add r4,r0,r4
subf r6,r0,r6
srwi r0,r4,2
andi. r4,r4,3
mtctr r0
bdz 7f
1: stwu r5,4(r6)
bdnz 1b
/* clear byte sized chunks */
7: cmpwi 0,r4,0
beqlr
mtctr r4
addi r6,r6,3
8: stbu r5,1(r6)
bdnz 8b
blr
90: mr r3,r4
blr
91: mfctr r3
slwi r3,r3,2
add r3,r3,r4
blr
92: mfctr r3
blr
.section __ex_table,"a"
.align 3
.llong 11b,90b
.llong 1b,91b
.llong 8b,92b
.text
/* r3 = dst, r4 = src, r5 = count */
_GLOBAL(__strncpy_from_user)
addi r6,r3,-1
addi r4,r4,-1
cmpwi 0,r5,0
beq 2f
mtctr r5
1: lbzu r0,1(r4)
cmpwi 0,r0,0
stbu r0,1(r6)
bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */
beq 3f
2: addi r6,r6,1
3: subf r3,r3,r6
blr
99: li r3,-EFAULT
blr
.section __ex_table,"a"
.align 3
.llong 1b,99b
.text
/* r3 = str, r4 = len (> 0) */
_GLOBAL(__strnlen_user)
addi r7,r3,-1
mtctr r4 /* ctr = len */
1: lbzu r0,1(r7) /* get next byte */
cmpwi 0,r0,0
bdnzf 2,1b /* loop if --ctr != 0 && byte != 0 */
addi r7,r7,1
subf r3,r3,r7 /* number of bytes we have looked at */
beqlr /* return if we found a 0 byte */
cmpw 0,r3,r4 /* did we look at all len bytes? */
blt 99f /* if not, must have hit top */
addi r3,r4,1 /* return len + 1 to indicate no null found */
blr
99: li r3,0 /* bad address, return 0 */
blr
.section __ex_table,"a"
.align 3
.llong 1b,99b
