ArmPkg/Library/CompilerIntrinsicsLib/memcmp_ms.c

   1 // ------------------------------------------------------------------------------
   2 //
   3 // Copyright (c) 2019, Pete Batard. All rights reserved.
   4 // Copyright (c) 2021, Arm Limited. All rights reserved.<BR>
   5 //
   6 // SPDX-License-Identifier: BSD-2-Clause-Patent
   7 //
   8 // ------------------------------------------------------------------------------
   9
  10 #if defined (_M_ARM64)
  11 typedef unsigned __int64 size_t;
  12 #else
  13 typedef unsigned __int32 size_t;
  14 #endif
  15
  16 int
  17 memcmp (
  18   void *,
  19   void *,
  20   size_t
  21   );
  22
  23 #pragma intrinsic(memcmp)
  24 #pragma function(memcmp)
  25 int
  26 memcmp (
  27   const void  *s1,
  28   const void  *s2,
  29   size_t      n
  30   )
  31 {
  32   unsigned char const  *t1;
  33   unsigned char const  *t2;
  34
  35   t1 = s1;
  36   t2 = s2;
  37
  38   while (n-- != 0) {
  39     if (*t1 != *t2) {
  40       return (int)*t1 - (int)*t2;
  41     }
  42
  43     t1++;
  44     t2++;
  45   }
  46
  47   return 0;
  48 }