reactos/lib/rtl/i386/rtlswap.S
2013-06-16 22:01:41 +00:00

56 lines
1.3 KiB
ArmAsm

/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS Run-Time Library
* PURPOSE: Byte swap functions
* FILE: lib/rtl/i386/rtlswap.S
* PROGRAMER: Alex Ionescu (alex.ionescu@reactos.org)
* Timo Kreuzer (timo.kreuzer@reactos.org)
*/
#include <asm.inc>
PUBLIC @RtlUshortByteSwap@4
PUBLIC @RtlUlongByteSwap@4
PUBLIC @RtlUlonglongByteSwap@8
/* FUNCTIONS ***************************************************************/
.code
FUNC @RtlUshortByteSwap@4
FPO 0, 0, 0, 0, 0, FRAME_FPO
/* Swap high and low bits */
mov ah, cl
mov al, ch
ret
ENDFUNC
FUNC @RtlUlongByteSwap@4
FPO 0, 0, 0, 0, 0, FRAME_FPO
/* Swap high and low bits */
mov eax, ecx
bswap eax
ret
ENDFUNC
FUNC @RtlUlonglongByteSwap@8
FPO 0, 2, 0, 0, 0, FRAME_FPO
/* Get 64-bit integer */
mov eax, [esp+8]
mov edx, [esp+4]
/* Swap it */
bswap edx
bswap eax
/* Return it (NOTE: this might look wrong, since fastcall functions
should clean up the stack, even if the first parameter is an ULONGLONG,
and therefore put on tthe stack instead of in ecx and edx,
but thats exactly how the function behaves on Windows! */
ret
ENDFUNC
END