reactos/sdk/lib/crt/stdlib/rot.c
2020-11-16 16:58:10 +01:00

87 lines
2 KiB
C

/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS system libraries
* FILE: lib/sdk/crt/stdlib/rot.c
* PURPOSE: Performs a bitwise rotation
* PROGRAMER: Ariadne
* UPDATE HISTORY:
* 03/04/99: Created
*/
#include <stdlib.h>
#ifdef __clang__
#define _rotl __function_rotl
#define _rotr __function_rotr
#define _lrotl __function_lrotl
#define _lrotr __function_lrotr
#elif defined(_MSC_VER)
#pragma function(_rotr, _rotl, _rotr, _lrotl, _lrotr)
#endif
#if defined (__clang__) && !defined(_MSC_VER)
#define ASM_ALIAS __asm__
#else
#define ASM_ALIAS(x)
#endif
unsigned int _rotr( unsigned int value, int shift ) ASM_ALIAS("__rotr");
unsigned long _lrotr(unsigned long value, int shift) ASM_ALIAS("__lrotr");
unsigned int _rotl( unsigned int value, int shift ) ASM_ALIAS("__rotl");
unsigned long _lrotl( unsigned long value, int shift ) ASM_ALIAS("__lrotl");
/*
* @implemented
*/
unsigned int _rotl( unsigned int value, int shift )
{
int max_bits = sizeof(unsigned int)<<3;
if ( shift < 0 )
return _rotr(value,-shift);
if ( shift > max_bits )
shift = shift % max_bits;
return (value << shift) | (value >> (max_bits-shift));
}
/*
* @implemented
*/
unsigned int _rotr( unsigned int value, int shift )
{
int max_bits = sizeof(unsigned int)<<3;
if ( shift < 0 )
return _rotl(value,-shift);
if ( shift > max_bits )
shift = shift % max_bits;
return (value >> shift) | (value << (max_bits-shift));
}
/*
* @implemented
*/
unsigned long _lrotl( unsigned long value, int shift )
{
int max_bits = sizeof(unsigned long)<<3;
if ( shift < 0 )
return _lrotr(value,-shift);
if ( shift > max_bits )
shift = shift % max_bits;
return (value << shift) | (value >> (max_bits-shift));
}
/*
* @implemented
*/
unsigned long _lrotr( unsigned long value, int shift )
{
int max_bits = sizeof(unsigned long)<<3;
if ( shift < 0 )
return _lrotl(value,-shift);
if ( shift > max_bits )
shift = shift % max_bits;
return (value >> shift) | (value << (max_bits-shift));
}