michael@0: #if !defined(_mathops_H)
michael@0: # define _mathops_H (1)
michael@0: # include <ogg/ogg.h>
michael@0: 
michael@0: # if __GNUC_PREREQ(3,4)
michael@0: #  include <limits.h>
michael@0: /*Note the casts to (int) below: this prevents OC_CLZ{32|64}_OFFS from
michael@0:    "upgrading" the type of an entire expression to an (unsigned) size_t.*/
michael@0: #  if INT_MAX>=2147483647
michael@0: #   define OC_CLZ32_OFFS ((int)sizeof(unsigned)*CHAR_BIT)
michael@0: #   define OC_CLZ32(_x) (__builtin_clz(_x))
michael@0: #  elif LONG_MAX>=2147483647L
michael@0: #   define OC_CLZ32_OFFS ((int)sizeof(unsigned long)*CHAR_BIT)
michael@0: #   define OC_CLZ32(_x) (__builtin_clzl(_x))
michael@0: #  endif
michael@0: #  if INT_MAX>=9223372036854775807LL
michael@0: #   define OC_CLZ64_OFFS ((int)sizeof(unsigned)*CHAR_BIT)
michael@0: #   define OC_CLZ64(_x) (__builtin_clz(_x))
michael@0: #  elif LONG_MAX>=9223372036854775807LL
michael@0: #   define OC_CLZ64_OFFS ((int)sizeof(unsigned long)*CHAR_BIT)
michael@0: #   define OC_CLZ64(_x) (__builtin_clzl(_x))
michael@0: #  elif LLONG_MAX>=9223372036854775807LL|| \
michael@0:     __LONG_LONG_MAX__>=9223372036854775807LL
michael@0: #   define OC_CLZ64_OFFS ((int)sizeof(unsigned long long)*CHAR_BIT)
michael@0: #   define OC_CLZ64(_x) (__builtin_clzll(_x))
michael@0: #  endif
michael@0: # endif
michael@0: 
michael@0: 
michael@0: 
michael@0: /**
michael@0:  * oc_ilog32 - Integer binary logarithm of a 32-bit value.
michael@0:  * @_v: A 32-bit value.
michael@0:  * Returns floor(log2(_v))+1, or 0 if _v==0.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  * The OC_ILOG_32() or OC_ILOGNZ_32() macros may be able to use a builtin
michael@0:  *  function instead, which should be faster.
michael@0:  */
michael@0: int oc_ilog32(ogg_uint32_t _v);
michael@0: /**
michael@0:  * oc_ilog64 - Integer binary logarithm of a 64-bit value.
michael@0:  * @_v: A 64-bit value.
michael@0:  * Returns floor(log2(_v))+1, or 0 if _v==0.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  * The OC_ILOG_64() or OC_ILOGNZ_64() macros may be able to use a builtin
michael@0:  *  function instead, which should be faster.
michael@0:  */
michael@0: int oc_ilog64(ogg_int64_t _v);
michael@0: 
michael@0: 
michael@0: # if defined(OC_CLZ32)
michael@0: /**
michael@0:  * OC_ILOGNZ_32 - Integer binary logarithm of a non-zero 32-bit value.
michael@0:  * @_v: A non-zero 32-bit value.
michael@0:  * Returns floor(log2(_v))+1.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  * If _v is zero, the return value is undefined; use OC_ILOG_32() instead.
michael@0:  */
michael@0: #  define OC_ILOGNZ_32(_v) (OC_CLZ32_OFFS-OC_CLZ32(_v))
michael@0: /**
michael@0:  * OC_ILOG_32 - Integer binary logarithm of a 32-bit value.
michael@0:  * @_v: A 32-bit value.
michael@0:  * Returns floor(log2(_v))+1, or 0 if _v==0.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  */
michael@0: #  define OC_ILOG_32(_v)   (OC_ILOGNZ_32(_v)&-!!(_v))
michael@0: # else
michael@0: #  define OC_ILOGNZ_32(_v) (oc_ilog32(_v))
michael@0: #  define OC_ILOG_32(_v)   (oc_ilog32(_v))
michael@0: # endif
michael@0: 
michael@0: # if defined(CLZ64)
michael@0: /**
michael@0:  * OC_ILOGNZ_64 - Integer binary logarithm of a non-zero 64-bit value.
michael@0:  * @_v: A non-zero 64-bit value.
michael@0:  * Returns floor(log2(_v))+1.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  * If _v is zero, the return value is undefined; use OC_ILOG_64() instead.
michael@0:  */
michael@0: #  define OC_ILOGNZ_64(_v) (CLZ64_OFFS-CLZ64(_v))
michael@0: /**
michael@0:  * OC_ILOG_64 - Integer binary logarithm of a 64-bit value.
michael@0:  * @_v: A 64-bit value.
michael@0:  * Returns floor(log2(_v))+1, or 0 if _v==0.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  */
michael@0: #  define OC_ILOG_64(_v)   (OC_ILOGNZ_64(_v)&-!!(_v))
michael@0: # else
michael@0: #  define OC_ILOGNZ_64(_v) (oc_ilog64(_v))
michael@0: #  define OC_ILOG_64(_v)   (oc_ilog64(_v))
michael@0: # endif
michael@0: 
michael@0: # define OC_STATIC_ILOG0(_v) (!!(_v))
michael@0: # define OC_STATIC_ILOG1(_v) (((_v)&0x2)?2:OC_STATIC_ILOG0(_v))
michael@0: # define OC_STATIC_ILOG2(_v) \
michael@0:  (((_v)&0xC)?2+OC_STATIC_ILOG1((_v)>>2):OC_STATIC_ILOG1(_v))
michael@0: # define OC_STATIC_ILOG3(_v) \
michael@0:  (((_v)&0xF0)?4+OC_STATIC_ILOG2((_v)>>4):OC_STATIC_ILOG2(_v))
michael@0: # define OC_STATIC_ILOG4(_v) \
michael@0:  (((_v)&0xFF00)?8+OC_STATIC_ILOG3((_v)>>8):OC_STATIC_ILOG3(_v))
michael@0: # define OC_STATIC_ILOG5(_v) \
michael@0:  (((_v)&0xFFFF0000)?16+OC_STATIC_ILOG4((_v)>>16):OC_STATIC_ILOG4(_v))
michael@0: # define OC_STATIC_ILOG6(_v) \
michael@0:  (((_v)&0xFFFFFFFF00000000ULL)?32+OC_STATIC_ILOG5((_v)>>32):OC_STATIC_ILOG5(_v))
michael@0: /**
michael@0:  * OC_STATIC_ILOG_32 - The integer logarithm of an (unsigned, 32-bit) constant.
michael@0:  * @_v: A non-negative 32-bit constant.
michael@0:  * Returns floor(log2(_v))+1, or 0 if _v==0.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  * This macro is suitable for evaluation at compile time, but it should not be
michael@0:  *  used on values that can change at runtime, as it operates via exhaustive
michael@0:  *  search.
michael@0:  */
michael@0: # define OC_STATIC_ILOG_32(_v) (OC_STATIC_ILOG5((ogg_uint32_t)(_v)))
michael@0: /**
michael@0:  * OC_STATIC_ILOG_64 - The integer logarithm of an (unsigned, 64-bit) constant.
michael@0:  * @_v: A non-negative 64-bit constant.
michael@0:  * Returns floor(log2(_v))+1, or 0 if _v==0.
michael@0:  * This is the number of bits that would be required to represent _v in two's
michael@0:  *  complement notation with all of the leading zeros stripped.
michael@0:  * This macro is suitable for evaluation at compile time, but it should not be
michael@0:  *  used on values that can change at runtime, as it operates via exhaustive
michael@0:  *  search.
michael@0:  */
michael@0: # define OC_STATIC_ILOG_64(_v) (OC_STATIC_ILOG6((ogg_int64_t)(_v)))
michael@0: 
michael@0: #define OC_Q57(_v) ((ogg_int64_t)(_v)<<57)
michael@0: #define OC_Q10(_v) ((_v)<<10)
michael@0: 
michael@0: ogg_int64_t oc_bexp64(ogg_int64_t _z);
michael@0: ogg_int64_t oc_blog64(ogg_int64_t _w);
michael@0: 
michael@0: ogg_uint32_t oc_bexp32_q10(int _z);
michael@0: int oc_blog32_q10(ogg_uint32_t _w);
michael@0: 
michael@0: #endif