1/* 2 * Copyright (C) 2023 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28/* 29 * Copyright (c) 2023 SiFive, Inc. 30 * All rights reserved. 31 * 32 * Redistribution and use in source and binary forms, with or without 33 * modification, are permitted provided that the following conditions 34 * are met: 35 * 1. Redistributions of source code must retain the above copyright 36 * notice, this list of conditions and the following disclaimer. 37 * 2. Redistributions in binary form must reproduce the above copyright 38 * notice, this list of conditions and the following disclaimer in the 39 * documentation and/or other materials provided with the distribution. 40 * 3. The name of the company may not be used to endorse or promote 41 * products derived from this software without specific prior written 42 * permission. 43 * 44 * THIS SOFTWARE IS PROVIDED BY SIFIVE INC ``AS IS'' AND ANY EXPRESS OR IMPLIED 45 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 46 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 47 * IN NO EVENT SHALL SIFIVE INC BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 48 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 49 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 50 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 51 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 52 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 53 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 54 */ 55 56#include <private/bionic_asm.h> 57 58#define iResult a0 59 60#define pStr1 a0 61#define pStr2 a1 62#define iLength a2 63 64#define iVL a3 65#define iTemp1 a4 66#define iTemp2 a5 67 68#define ELEM_LMUL_SETTING m1 69#define vStr1 v0 70#define vStr2 v4 71#define vMask1 v8 72#define vMask2 v9 73 74ENTRY(strncmp_v) 75 76 beqz iLength, L(zero_length) 77 78L(loop): 79 vsetvli iVL, iLength, e8, ELEM_LMUL_SETTING, ta, ma 80 81 vle8ff.v vStr1, (pStr1) 82 # vStr1[i] == 0 83 vmseq.vx vMask1, vStr1, zero 84 85 vle8ff.v vStr2, (pStr2) 86 # vStr1[i] != vStr2[i] 87 vmsne.vv vMask2, vStr1, vStr2 88 89 csrr iVL, vl 90 91 # r = mask1 | mask2 92 # We could use vfirst.m to get the first zero char or the 93 # first different char between str1 and str2. 94 vmor.mm vMask1, vMask1, vMask2 95 96 sub iLength, iLength, iVL 97 98 vfirst.m iTemp1, vMask1 99 100 bgez iTemp1, L(end_loop) 101 102 add pStr1, pStr1, iVL 103 add pStr2, pStr2, iVL 104 bnez iLength, L(loop) 105L(end_loop): 106 107 add pStr1, pStr1, iTemp1 108 add pStr2, pStr2, iTemp1 109 lbu iTemp1, 0(pStr1) 110 lbu iTemp2, 0(pStr2) 111 112 sub iResult, iTemp1, iTemp2 113 ret 114 115L(zero_length): 116 li iResult, 0 117 ret 118 119END(strncmp_v) 120