CryptoPkg/Library/IntrinsicLib/Ia32/MathRShiftU64.nasm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
   4 ; SPDX-License-Identifier: BSD-2-Clause-Patent
   5 ;
   6 ; Module Name:
   7 ;
   8 ;   MathRShiftU64.nasm
   9 ;
  10 ; Abstract:
  11 ;
  12 ;   64-bit Math Worker Function.
  13 ;   Shifts a 64-bit unsigned value right by a certain number of bits.
  14 ;
  15 ;------------------------------------------------------------------------------
  16
  17     SECTION .text
  18
  19 ;------------------------------------------------------------------------------
  20 ;
  21 ; void __cdecl __ashrdi3 (void)
  22 ;
  23 ;------------------------------------------------------------------------------
  24 global ASM_PFX(__ashrdi3)
  25 ASM_PFX(__ashrdi3):
  26     cmp cl,0x40
  27     jnc _Exit
  28     cmp cl,0x20
  29     jnc More32
  30     shrd eax,edx,cl
  31     shr edx,cl
  32     ret
  33 More32:
  34     mov eax,edx
  35     xor edx,edx
  36     and cl,0x1f
  37     shr eax,cl
  38     ret
  39 _Exit:
  40     xor eax,eax
  41     xor edx,edx
  42     ret
  43