/* * SPDX-License-Identifier: MIT * * Copyright (C) 2013-2024 OpenMV, LLC. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * * Fast unaligned memcpy functions. */ #include #include #include "cmsis_compiler.h" #include "unaligned_memcpy.h" // ARM Cortex-M4/M7 Processors can access memory using unaligned 32-bit reads/writes. void *unaligned_memcpy(void *dest, void *src, size_t n) { #if (__ARM_ARCH > 6) // TODO: Make this faster using only 32-bit aligned reads/writes with data shifting. uint32_t *dest32 = (uint32_t *) dest; uint32_t *src32 = (uint32_t *) src; for (; n > 4; n -= 4) { *dest32++ = *src32++; } uint8_t *dest8 = (uint8_t *) dest32; uint8_t *src8 = (uint8_t *) src32; for (; n > 0; n -= 1) { *dest8++ = *src8++; } return dest; #else return memcpy(dest, src, n); #endif } // ARM Cortex-M4/M7 Processors can access memory using unaligned 32-bit reads/writes. void *unaligned_memcpy_rev16(void *dest, void *src, size_t n) { uint32_t *dest32 = (uint32_t *) dest; uint32_t *src32 = (uint32_t *) src; #if (__ARM_ARCH > 6) // TODO: Make this faster using only 32-bit aligned reads/writes with data shifting. for (; n > 2; n -= 2) { *dest32++ = __REV16(*src32++); } #endif uint16_t *dest16 = (uint16_t *) dest32; uint16_t *src16 = (uint16_t *) src32; for (; n > 0; n -= 1) { *dest16++ = __REV16(*src16++); } return dest; } void *unaligned_2_to_1_memcpy(void *dest, void *src, size_t n) { uint32_t *dest32 = (uint32_t *) dest; uint32_t *src32 = (uint32_t *) src; #if (__ARM_ARCH > 6) // TODO: Make this faster using only 32-bit aligned reads/writes with data shifting. for (; n > 4; n -= 4) { uint32_t tmp1 = *src32++; uint32_t tmp2 = *src32++; *dest32++ = (tmp1 & 0xff) | ((tmp1 >> 8) & 0xff00) | ((tmp2 & 0xff) << 16) | ((tmp2 & 0xff0000) << 8); } #endif uint8_t *dest8 = (uint8_t *) dest32; uint16_t *src16 = (uint16_t *) src32; for (; n > 0; n -= 1) { *dest8++ = *src16++; } return dest; }