18c2ecf20Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */ 28c2ecf20Sopenharmony_ci/* 38c2ecf20Sopenharmony_ci * arch/alpha/lib/strcat.S 48c2ecf20Sopenharmony_ci * Contributed by Richard Henderson (rth@tamu.edu) 58c2ecf20Sopenharmony_ci * 68c2ecf20Sopenharmony_ci * Append a null-terminated string from SRC to DST. 78c2ecf20Sopenharmony_ci */ 88c2ecf20Sopenharmony_ci#include <asm/export.h> 98c2ecf20Sopenharmony_ci 108c2ecf20Sopenharmony_ci .text 118c2ecf20Sopenharmony_ci 128c2ecf20Sopenharmony_ci .align 3 138c2ecf20Sopenharmony_ci .globl strcat 148c2ecf20Sopenharmony_ci .ent strcat 158c2ecf20Sopenharmony_cistrcat: 168c2ecf20Sopenharmony_ci .frame $30, 0, $26 178c2ecf20Sopenharmony_ci .prologue 0 188c2ecf20Sopenharmony_ci 198c2ecf20Sopenharmony_ci mov $16, $0 # set up return value 208c2ecf20Sopenharmony_ci 218c2ecf20Sopenharmony_ci /* Find the end of the string. */ 228c2ecf20Sopenharmony_ci 238c2ecf20Sopenharmony_ci ldq_u $1, 0($16) # load first quadword (a0 may be misaligned) 248c2ecf20Sopenharmony_ci lda $2, -1 258c2ecf20Sopenharmony_ci insqh $2, $16, $2 268c2ecf20Sopenharmony_ci andnot $16, 7, $16 278c2ecf20Sopenharmony_ci or $2, $1, $1 288c2ecf20Sopenharmony_ci cmpbge $31, $1, $2 # bits set iff byte == 0 298c2ecf20Sopenharmony_ci bne $2, $found 308c2ecf20Sopenharmony_ci 318c2ecf20Sopenharmony_ci$loop: ldq $1, 8($16) 328c2ecf20Sopenharmony_ci addq $16, 8, $16 338c2ecf20Sopenharmony_ci cmpbge $31, $1, $2 348c2ecf20Sopenharmony_ci beq $2, $loop 358c2ecf20Sopenharmony_ci 368c2ecf20Sopenharmony_ci$found: negq $2, $3 # clear all but least set bit 378c2ecf20Sopenharmony_ci and $2, $3, $2 388c2ecf20Sopenharmony_ci 398c2ecf20Sopenharmony_ci and $2, 0xf0, $3 # binary search for that set bit 408c2ecf20Sopenharmony_ci and $2, 0xcc, $4 418c2ecf20Sopenharmony_ci and $2, 0xaa, $5 428c2ecf20Sopenharmony_ci cmovne $3, 4, $3 438c2ecf20Sopenharmony_ci cmovne $4, 2, $4 448c2ecf20Sopenharmony_ci cmovne $5, 1, $5 458c2ecf20Sopenharmony_ci addq $3, $4, $3 468c2ecf20Sopenharmony_ci addq $16, $5, $16 478c2ecf20Sopenharmony_ci addq $16, $3, $16 488c2ecf20Sopenharmony_ci 498c2ecf20Sopenharmony_ci /* Now do the append. */ 508c2ecf20Sopenharmony_ci 518c2ecf20Sopenharmony_ci mov $26, $23 528c2ecf20Sopenharmony_ci br __stxcpy 538c2ecf20Sopenharmony_ci 548c2ecf20Sopenharmony_ci .end strcat 558c2ecf20Sopenharmony_ciEXPORT_SYMBOL(strcat); 56