strcat.S
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/*
* 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