secure_fw/partitions/lib/sprt/crt_memcpy.c

/*
 * Copyright (c) 2019-2020, Arm Limited. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 *
 */

#include "crt_impl_private.h"

void *memcpy(void *dest, const void *src, size_t n)
{
    union tfm_mem_addr_t p_dest, p_src;

    p_dest.uint_addr = (uintptr_t)dest;
    p_src.uint_addr = (uintptr_t)src;

    /* Byte copy for unaligned address. check the last bit of address. */
    while (n && (GET_MEM_ADDR_BIT0(p_dest.uint_addr) ||
           GET_MEM_ADDR_BIT0(p_src.uint_addr))) {
        *p_dest.p_byte++ = *p_src.p_byte++;
        n--;
    }

    /*
     * Double byte copy for aligned address.
     * Check the 2nd last bit of address.
     */
    while (n >= sizeof(uint16_t) && (GET_MEM_ADDR_BIT1(p_dest.uint_addr) ||
           GET_MEM_ADDR_BIT1(p_src.uint_addr))) {
        *(p_dest.p_dbyte)++ = *(p_src.p_dbyte)++;
        n -= sizeof(uint16_t);
    }

    /* Quad byte copy for aligned address. */
    while (n >= sizeof(uint32_t)) {
        *(p_dest.p_qbyte)++ = *(p_src.p_qbyte)++;
        n -= sizeof(uint32_t);
    }

    /* Byte copy for the remaining bytes. */
    while (n--) {
        *p_dest.p_byte++ = *p_src.p_byte++;
    }

    return dest;
}