src/arch/x86/memcpy.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <string.h>
   4 #include <stdbool.h>
   5 #include <asan.h>
   6
   7 void *memcpy(void *dest, const void *src, size_t n)
   8 {
   9         unsigned long d0, d1, d2;
  10
  11 #if (ENV_ROMSTAGE && CONFIG(ASAN_IN_ROMSTAGE)) || \
  12                 (ENV_RAMSTAGE && CONFIG(ASAN_IN_RAMSTAGE))
  13         check_memory_region((unsigned long)src, n, false, _RET_IP_);
  14         check_memory_region((unsigned long)dest, n, true, _RET_IP_);
  15 #endif
  16
  17         asm volatile(
  18 #if ENV_X86_64
  19                 "rep ; movsd\n\t"
  20                 "mov %4,%%rcx\n\t"
  21 #else
  22                 "rep ; movsl\n\t"
  23                 "movl %4,%%ecx\n\t"
  24 #endif
  25                 "rep ; movsb\n\t"
  26                 : "=&c" (d0), "=&D" (d1), "=&S" (d2)
  27                 : "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
  28                 : "memory"
  29         );
  30
  31         return dest;
  32 }