162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */ 262306a36Sopenharmony_ci/* 362306a36Sopenharmony_ci * arch/alpha/lib/strcat.S 462306a36Sopenharmony_ci * Contributed by Richard Henderson (rth@tamu.edu) 562306a36Sopenharmony_ci * 662306a36Sopenharmony_ci * Append a null-terminated string from SRC to DST. 762306a36Sopenharmony_ci */ 862306a36Sopenharmony_ci#include <linux/export.h> 962306a36Sopenharmony_ci 1062306a36Sopenharmony_ci .text 1162306a36Sopenharmony_ci 1262306a36Sopenharmony_ci .align 3 1362306a36Sopenharmony_ci .globl strcat 1462306a36Sopenharmony_ci .ent strcat 1562306a36Sopenharmony_cistrcat: 1662306a36Sopenharmony_ci .frame $30, 0, $26 1762306a36Sopenharmony_ci .prologue 0 1862306a36Sopenharmony_ci 1962306a36Sopenharmony_ci mov $16, $0 # set up return value 2062306a36Sopenharmony_ci 2162306a36Sopenharmony_ci /* Find the end of the string. */ 2262306a36Sopenharmony_ci 2362306a36Sopenharmony_ci ldq_u $1, 0($16) # load first quadword (a0 may be misaligned) 2462306a36Sopenharmony_ci lda $2, -1 2562306a36Sopenharmony_ci insqh $2, $16, $2 2662306a36Sopenharmony_ci andnot $16, 7, $16 2762306a36Sopenharmony_ci or $2, $1, $1 2862306a36Sopenharmony_ci cmpbge $31, $1, $2 # bits set iff byte == 0 2962306a36Sopenharmony_ci bne $2, $found 3062306a36Sopenharmony_ci 3162306a36Sopenharmony_ci$loop: ldq $1, 8($16) 3262306a36Sopenharmony_ci addq $16, 8, $16 3362306a36Sopenharmony_ci cmpbge $31, $1, $2 3462306a36Sopenharmony_ci beq $2, $loop 3562306a36Sopenharmony_ci 3662306a36Sopenharmony_ci$found: negq $2, $3 # clear all but least set bit 3762306a36Sopenharmony_ci and $2, $3, $2 3862306a36Sopenharmony_ci 3962306a36Sopenharmony_ci and $2, 0xf0, $3 # binary search for that set bit 4062306a36Sopenharmony_ci and $2, 0xcc, $4 4162306a36Sopenharmony_ci and $2, 0xaa, $5 4262306a36Sopenharmony_ci cmovne $3, 4, $3 4362306a36Sopenharmony_ci cmovne $4, 2, $4 4462306a36Sopenharmony_ci cmovne $5, 1, $5 4562306a36Sopenharmony_ci addq $3, $4, $3 4662306a36Sopenharmony_ci addq $16, $5, $16 4762306a36Sopenharmony_ci addq $16, $3, $16 4862306a36Sopenharmony_ci 4962306a36Sopenharmony_ci /* Now do the append. */ 5062306a36Sopenharmony_ci 5162306a36Sopenharmony_ci mov $26, $23 5262306a36Sopenharmony_ci br __stxcpy 5362306a36Sopenharmony_ci 5462306a36Sopenharmony_ci .end strcat 5562306a36Sopenharmony_ciEXPORT_SYMBOL(strcat); 56