audk/CryptoPkg/Library/IntrinsicLib/Ia32/MathRShiftU64.S

67 lines
1.6 KiB
ArmAsm

#------------------------------------------------------------------------------
#
# Copyright (c) 2014, Intel Corporation. All rights reserved.<BR>
# This program and the accompanying materials
# are licensed and made available under the terms and conditions of the BSD License
# which accompanies this distribution. The full text of the license may be found at
# http://opensource.org/licenses/bsd-license.php.
#
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#
# Module Name:
#
# MathRShiftU64.S
#
# Abstract:
#
# 64-bit Math Worker Function.
# Shifts a 64-bit unsigned value right by a certain number of bits.
#
#------------------------------------------------------------------------------
.686:
.code:
ASM_GLOBAL ASM_PFX(__ashrdi3)
#------------------------------------------------------------------------------
#
# void __cdecl __ashrdi3 (void)
#
#------------------------------------------------------------------------------
ASM_PFX(__ashrdi3):
#
# Checking: Only handle 64bit shifting or more
#
cmpb $64, %cl
jae _Exit
#
# Handle shifting between 0 and 31 bits
#
cmpb $32, %cl
jae More32
shrd %cl, %edx, %eax
shr %cl, %edx
ret
#
# Handle shifting of 32-63 bits
#
More32:
movl %edx, %eax
xor %edx, %edx
and $31, %cl
shr %cl, %eax
ret
#
# Invalid number (less then 32bits), return 0
#
_Exit:
xor %eax, %eax
xor %edx, %edx
ret