1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun/* 3*4882a593Smuzhiyun * arch/alpha/lib/strcat.S 4*4882a593Smuzhiyun * Contributed by Richard Henderson (rth@tamu.edu) 5*4882a593Smuzhiyun * 6*4882a593Smuzhiyun * Append a null-terminated string from SRC to DST. 7*4882a593Smuzhiyun */ 8*4882a593Smuzhiyun#include <asm/export.h> 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun .text 11*4882a593Smuzhiyun 12*4882a593Smuzhiyun .align 3 13*4882a593Smuzhiyun .globl strcat 14*4882a593Smuzhiyun .ent strcat 15*4882a593Smuzhiyunstrcat: 16*4882a593Smuzhiyun .frame $30, 0, $26 17*4882a593Smuzhiyun .prologue 0 18*4882a593Smuzhiyun 19*4882a593Smuzhiyun mov $16, $0 # set up return value 20*4882a593Smuzhiyun 21*4882a593Smuzhiyun /* Find the end of the string. */ 22*4882a593Smuzhiyun 23*4882a593Smuzhiyun ldq_u $1, 0($16) # load first quadword (a0 may be misaligned) 24*4882a593Smuzhiyun lda $2, -1 25*4882a593Smuzhiyun insqh $2, $16, $2 26*4882a593Smuzhiyun andnot $16, 7, $16 27*4882a593Smuzhiyun or $2, $1, $1 28*4882a593Smuzhiyun cmpbge $31, $1, $2 # bits set iff byte == 0 29*4882a593Smuzhiyun bne $2, $found 30*4882a593Smuzhiyun 31*4882a593Smuzhiyun$loop: ldq $1, 8($16) 32*4882a593Smuzhiyun addq $16, 8, $16 33*4882a593Smuzhiyun cmpbge $31, $1, $2 34*4882a593Smuzhiyun beq $2, $loop 35*4882a593Smuzhiyun 36*4882a593Smuzhiyun$found: negq $2, $3 # clear all but least set bit 37*4882a593Smuzhiyun and $2, $3, $2 38*4882a593Smuzhiyun 39*4882a593Smuzhiyun and $2, 0xf0, $3 # binary search for that set bit 40*4882a593Smuzhiyun and $2, 0xcc, $4 41*4882a593Smuzhiyun and $2, 0xaa, $5 42*4882a593Smuzhiyun cmovne $3, 4, $3 43*4882a593Smuzhiyun cmovne $4, 2, $4 44*4882a593Smuzhiyun cmovne $5, 1, $5 45*4882a593Smuzhiyun addq $3, $4, $3 46*4882a593Smuzhiyun addq $16, $5, $16 47*4882a593Smuzhiyun addq $16, $3, $16 48*4882a593Smuzhiyun 49*4882a593Smuzhiyun /* Now do the append. */ 50*4882a593Smuzhiyun 51*4882a593Smuzhiyun mov $26, $23 52*4882a593Smuzhiyun br __stxcpy 53*4882a593Smuzhiyun 54*4882a593Smuzhiyun .end strcat 55*4882a593SmuzhiyunEXPORT_SYMBOL(strcat); 56