jpc_math.h
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61 
62 #ifndef JPC_MATH_H
63 #define JPC_MATH_H
64 
65 /******************************************************************************\
66 * Includes
67 \******************************************************************************/
68 
69 #include <assert.h>
70 #include <stdint.h>
71 
72 /******************************************************************************\
73 * Macros
74 \******************************************************************************/
75 
76 /* Compute the floor of the quotient of two integers. */
77 #define JPC_FLOORDIV(x, y) ((x) / (y))
78 
79 /* Compute the ceiling of the quotient of two integers. */
80 #define JPC_CEILDIV(x, y) (((x) + (y) - 1) / (y))
81 
82 /* Compute the floor of (x / 2^y). */
83 #define JPC_FLOORDIVPOW2(x, y) ((x) >> (y))
84 
85 /* Compute the ceiling of (x / 2^y). */
86 #define JPC_CEILDIVPOW2(x, y) (((x) + (1 << (y)) - 1) >> (y))
87 
88 /******************************************************************************\
89 * Functions.
90 \******************************************************************************/
91 
92 /* Calculate the bit position of the first leading one in a nonnegative
93  integer. */
94 int jpc_firstone(int_fast32_t x);
95 
96 /* Calculate the integer quantity floor(log2(x)), where x is a positive
97  integer. */
98 int jpc_floorlog2(int_fast32_t x);
99 
100 #endif