/* Copyright (c) 2012, Linaro Limited All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * 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. * Neither the name of the Linaro nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE COPYRIGHT HOLDER OR CONTRIBUTORS 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. */ /* * 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. */ /* Assumptions: * * ARMv8-a, AArch64, unaligned accesses * */ #define dstin x0 #define val x1 #define valw w1 #define count x2 #define dst x3 #define dstend x4 #define tmp1 x5 #define tmp1w w5 #define tmp2 x6 #define tmp2w w6 #define zva_len x7 #define zva_lenw w7 #define L(l) .L ## l .macro def_fn f p2align=0 .text .p2align \p2align .global \f .type \f, %function \f: .endm def_fn memset p2align=6 dup v0.16B, valw add dstend, dstin, count cmp count, 96 b.hi L(set_long) cmp count, 16 b.hs L(set_medium) mov val, v0.D[0] /* Set 0..15 bytes. */ tbz count, 3, 1f str val, [dstin] str val, [dstend, -8] ret nop 1: tbz count, 2, 2f str valw, [dstin] str valw, [dstend, -4] ret 2: cbz count, 3f strb valw, [dstin] tbz count, 1, 3f strh valw, [dstend, -2] 3: ret /* Set 17..96 bytes. */ L(set_medium): str q0, [dstin] tbnz count, 6, L(set96) str q0, [dstend, -16] tbz count, 5, 1f str q0, [dstin, 16] str q0, [dstend, -32] 1: ret .p2align 4 /* Set 64..96 bytes. Write 64 bytes from the start and 32 bytes from the end. */ L(set96): str q0, [dstin, 16] stp q0, q0, [dstin, 32] stp q0, q0, [dstend, -32] ret .p2align 3 nop L(set_long): and valw, valw, 255 bic dst, dstin, 15 str q0, [dstin] cmp count, 256 ccmp valw, 0, 0, cs b.eq L(try_zva) L(no_zva): sub count, dstend, dst /* Count is 16 too large. */ add dst, dst, 16 sub count, count, 64 + 16 /* Adjust count and bias for loop. */ 1: stp q0, q0, [dst], 64 stp q0, q0, [dst, -32] L(tail64): subs count, count, 64 b.hi 1b 2: stp q0, q0, [dstend, -64] stp q0, q0, [dstend, -32] ret .p2align 3 L(try_zva): mrs tmp1, dczid_el0 tbnz tmp1w, 4, L(no_zva) and tmp1w, tmp1w, 15 cmp tmp1w, 4 /* ZVA size is 64 bytes. */ b.ne L(zva_128) /* Write the first and last 64 byte aligned block using stp rather than using DC ZVA. This is faster on some cores. */ L(zva_64): str q0, [dst, 16] stp q0, q0, [dst, 32] bic dst, dst, 63 stp q0, q0, [dst, 64] stp q0, q0, [dst, 96] sub count, dstend, dst /* Count is now 128 too large. */ sub count, count, 128+64+64 /* Adjust count and bias for loop. */ add dst, dst, 128 nop 1: dc zva, dst add dst, dst, 64 subs count, count, 64 b.hi 1b stp q0, q0, [dst, 0] stp q0, q0, [dst, 32] stp q0, q0, [dstend, -64] stp q0, q0, [dstend, -32] ret .p2align 3 L(zva_128): cmp tmp1w, 5 /* ZVA size is 128 bytes. */ b.ne L(zva_other) str q0, [dst, 16] stp q0, q0, [dst, 32] stp q0, q0, [dst, 64] stp q0, q0, [dst, 96] bic dst, dst, 127 sub count, dstend, dst /* Count is now 128 too large. */ sub count, count, 128+128 /* Adjust count and bias for loop. */ add dst, dst, 128 1: dc zva, dst add dst, dst, 128 subs count, count, 128 b.hi 1b stp q0, q0, [dstend, -128] stp q0, q0, [dstend, -96] stp q0, q0, [dstend, -64] stp q0, q0, [dstend, -32] ret L(zva_other): mov tmp2w, 4 lsl zva_lenw, tmp2w, tmp1w add tmp1, zva_len, 64 /* Max alignment bytes written. */ cmp count, tmp1 blo L(no_zva) sub tmp2, zva_len, 1 add tmp1, dst, zva_len add dst, dst, 16 subs count, tmp1, dst /* Actual alignment bytes to write. */ bic tmp1, tmp1, tmp2 /* Aligned dc zva start address. */ beq 2f 1: stp q0, q0, [dst], 64 stp q0, q0, [dst, -32] subs count, count, 64 b.hi 1b 2: mov dst, tmp1 sub count, dstend, tmp1 /* Remaining bytes to write. */ subs count, count, zva_len b.lo 4f 3: dc zva, dst add dst, dst, zva_len subs count, count, zva_len b.hs 3b 4: add count, count, zva_len b L(tail64) .size memset, . - memset