53 lines
946 B
ArmAsm
53 lines
946 B
ArmAsm
|
/*
|
||
|
|
* arch/alpha/lib/strcat.S
|
||
|
|
* Contributed by Richard Henderson (rth@tamu.edu)
|
||
|
|
*
|
||
|
|
* Append a null-terminated string from SRC to DST.
|
||
|
|
*/
|
||
|
|
|
||
|
|
.text
|
||
|
|
|
||
|
|
.align 3
|
||
|
|
.globl strcat
|
||
|
|
.ent strcat
|
||
|
|
strcat:
|
||
|
|
.frame $30, 0, $26
|
||
|
|
.prologue 0
|
||
|
|
|
||
|
|
mov $16, $0 # set up return value
|
||
|
|
|
||
|
|
/* Find the end of the string. */
|
||
|
|
|
||
|
|
ldq_u $1, 0($16) # load first quadword (a0 may be misaligned)
|
||
|
|
lda $2, -1
|
||
|
|
insqh $2, $16, $2
|
||
|
|
andnot $16, 7, $16
|
||
|
|
or $2, $1, $1
|
||
|
|
cmpbge $31, $1, $2 # bits set iff byte == 0
|
||
|
|
bne $2, $found
|
||
|
|
|
||
|
|
$loop: ldq $1, 8($16)
|
||
|
|
addq $16, 8, $16
|
||
|
|
cmpbge $31, $1, $2
|
||
|
|
beq $2, $loop
|
||
|
|
|
||
|
|
$found: negq $2, $3 # clear all but least set bit
|
||
|
|
and $2, $3, $2
|
||
|
|
|
||
|
|
and $2, 0xf0, $3 # binary search for that set bit
|
||
|
|
and $2, 0xcc, $4
|
||
|
|
and $2, 0xaa, $5
|
||
|
|
cmovne $3, 4, $3
|
||
|
|
cmovne $4, 2, $4
|
||
|
|
cmovne $5, 1, $5
|
||
|
|
addq $3, $4, $3
|
||
|
|
addq $16, $5, $16
|
||
|
|
addq $16, $3, $16
|
||
|
|
|
||
|
|
/* Now do the append. */
|
||
|
|
|
||
|
|
mov $26, $23
|
||
|
|
br __stxcpy
|
||
|
|
|
||
|
|
.end strcat
|