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| /* SPDX-License-Identifier: GPL-2.0 */
| /*
| * arch/alpha/lib/strcat.S
| * Contributed by Richard Henderson (rth@tamu.edu)
| *
| * Append a null-terminated string from SRC to DST.
| */
| #include <asm/export.h>
|
| .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
| EXPORT_SYMBOL(strcat);
|
|
