1/* 2 * memcmp - compare memory 3 * 4 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 * See https://llvm.org/LICENSE.txt for license information. 6 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 */ 8 9#if __ARM_FEATURE_SVE 10/* Assumptions: 11 * 12 * ARMv8-a, AArch64 13 * SVE Available. 14 */ 15 16 .arch armv8-a+sve 17 .text 18 19 .globl __memcmp_aarch64_sve 20 .type __memcmp_aarch64_sve, %function 21 .p2align 4 22__memcmp_aarch64_sve: 23 mov x3, 0 /* initialize off */ 24 250: whilelo p0.b, x3, x2 /* while off < max */ 26 b.none 9f 27 28 ld1b z0.b, p0/z, [x0, x3] /* read vectors bounded by max. */ 29 ld1b z1.b, p0/z, [x1, x3] 30 31 /* Increment for a whole vector, even if we've only read a partial. 32 This is significantly cheaper than INCP, and since OFF is not 33 used after the loop it is ok to increment OFF past MAX. */ 34 incb x3 35 36 cmpne p1.b, p0/z, z0.b, z1.b /* while no inequalities */ 37 b.none 0b 38 39 /* Found inequality. */ 401: brkb p1.b, p0/z, p1.b /* find first such */ 41 lasta w0, p1, z0.b /* extract each byte */ 42 lasta w1, p1, z1.b 43 sub x0, x0, x1 /* return comparison */ 44 ret 45 46 /* Found end-of-count. */ 479: mov x0, 0 /* return equality */ 48 ret 49 50 .size __memcmp_aarch64_sve, . - __memcmp_aarch64_sve 51#endif 52