jpc_math.h

/*
 * Copyright (c) 2001-2002 Michael David Adams.
 * All rights reserved.
 */
 
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#ifndef JPC_MATH_H
#define JPC_MATH_H
 
/******************************************************************************\
* Includes
\******************************************************************************/
 
#include        <assert.h>
#include        <stdint.h>
 
/******************************************************************************\
* Macros
\******************************************************************************/
 
/* Compute the floor of the quotient of two integers. */
#define JPC_FLOORDIV(x, y)      ((x) / (y))
 
/* Compute the ceiling of the quotient of two integers. */
#define JPC_CEILDIV(x, y)       (((x) + (y) - 1) / (y))
 
/* Compute the floor of (x / 2^y). */
#define JPC_FLOORDIVPOW2(x, y)  ((x) >> (y))
 
/* Compute the ceiling of (x / 2^y). */
#define JPC_CEILDIVPOW2(x, y)   (((x) + (1 << (y)) - 1) >> (y))
 
/******************************************************************************\
* Functions.
\******************************************************************************/
 
/* Calculate the bit position of the first leading one in a nonnegative
  integer. */
int jpc_firstone(int_fast32_t x);
 
/* Calculate the integer quantity floor(log2(x)), where x is a positive
  integer. */
int jpc_floorlog2(int_fast32_t x);
 
#endif