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crt_memcpy.c
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1 /*
2  * Copyright (c) 2019-2020, Arm Limited. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  */
7 
8 #include "crt_impl_private.h"
9 
10 void *memcpy(void *dest, const void *src, size_t n)
11 {
12  union tfm_mem_addr_t p_dest, p_src;
13 
14  p_dest.uint_addr = (uintptr_t)dest;
15  p_src.uint_addr = (uintptr_t)src;
16 
17  /* Byte copy for unaligned address. check the last bit of address. */
18  while (n && (GET_MEM_ADDR_BIT0(p_dest.uint_addr) ||
19  GET_MEM_ADDR_BIT0(p_src.uint_addr))) {
20  *p_dest.p_byte++ = *p_src.p_byte++;
21  n--;
22  }
23 
24  /*
25  * Double byte copy for aligned address.
26  * Check the 2nd last bit of address.
27  */
28  while (n >= sizeof(uint16_t) && (GET_MEM_ADDR_BIT1(p_dest.uint_addr) ||
29  GET_MEM_ADDR_BIT1(p_src.uint_addr))) {
30  *(p_dest.p_dbyte)++ = *(p_src.p_dbyte)++;
31  n -= sizeof(uint16_t);
32  }
33 
34  /* Quad byte copy for aligned address. */
35  while (n >= sizeof(uint32_t)) {
36  *(p_dest.p_qbyte)++ = *(p_src.p_qbyte)++;
37  n -= sizeof(uint32_t);
38  }
39 
40  /* Byte copy for the remaining bytes. */
41  while (n--) {
42  *p_dest.p_byte++ = *p_src.p_byte++;
43  }
44 
45  return dest;
46 }
uint16_t * p_dbyte
#define GET_MEM_ADDR_BIT1(x)
uintptr_t uint_addr
uint32_t * p_qbyte
#define GET_MEM_ADDR_BIT0(x)
void * memcpy(void *dest, const void *src, size_t n)
Definition: crt_memcpy.c:10