MdePkg/Library/CompilerIntrinsicsLib/memmove_ms.c


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// ------------------------------------------------------------------------------
//
// Copyright (c) 2019, Pete Batard. All rights reserved.
// Copyright (c) 2021, Arm Limited. All rights reserved.<BR>
//
// SPDX-License-Identifier: BSD-2-Clause-Patent
//
// ------------------------------------------------------------------------------

#if defined (_M_ARM64)
typedef unsigned __int64 size_t;
#else
typedef unsigned __int32 size_t;
#endif

void *
memmove (
  void *,
  const void *,
  size_t
  );

#pragma intrinsic(memmove)
#pragma function(memmove)
void *
memmove (
  void        *dest,
  const void  *src,
  size_t      n
  )
{
  unsigned char        *d;
  unsigned char const  *s;

  d = dest;
  s = src;

  if (d < s) {
    while (n-- != 0) {
      *d++ = *s++;
    }
  } else {
    d += n;
    s += n;
    while (n-- != 0) {
      *--d = *--s;
    }
  }

  return dest;
}