/* * Copyright (c) 2015 ARM Ltd * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the company may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include .arm .syntax unified .global memset .type memset, %function memset: tst r0, #3 stmfd sp!, {r4, lr} beq 10f cmp r2, #0 sub r2, r2, #1 beq 9f and ip, r1, #255 mov r3, r0 b 2f 1: cmp r2, #0 sub r2, r2, #1 beq 9f 2: strb ip, [r3], #1 tst r3, #3 bne 1b 3: cmp r2, #3 bls 7f and lr, r1, #255 orr lr, lr, lr, asl #8 cmp r2, #15 orr lr, lr, lr, asl #16 bls 5f mov r4, r2 add ip, r3, #16 4: sub r4, r4, #16 cmp r4, #15 str lr, [ip, #-16] str lr, [ip, #-12] str lr, [ip, #-8] str lr, [ip, #-4] add ip, ip, #16 bhi 4b sub ip, r2, #16 bic ip, ip, #15 and r2, r2, #15 add ip, ip, #16 cmp r2, #3 add r3, r3, ip bls 7f 5: mov r4, r3 mov ip, r2 6: sub ip, ip, #4 cmp ip, #3 str lr, [r4], #4 bhi 6b sub ip, r2, #4 bic ip, ip, #3 add ip, ip, #4 add r3, r3, ip and r2, r2, #3 7: cmp r2, #0 andne r1, r1, #255 addne r2, r3, r2 beq 9f 8: strb r1, [r3], #1 cmp r3, r2 bne 8b 9: ldmfd sp!, {r4, lr} bx lr 10: mov r3, r0 b 3b .size memset, . - memset