git.sesse.net Git - plocate/blob - turbopfor-common.h

   1 #ifndef _TURBOPFOR_COMMON_H
   2 #define _TURBOPFOR_COMMON_H 1
   3
   4 // Common definitions and utilities between turbopfor.h (decode)
   5 // and turbopfor-encode.h (encode).
   6
   7 #include <limits.h>
   8
   9 enum BlockType {
  10         FOR = 0,
  11         PFOR_VB = 1,
  12         PFOR_BITMAP = 2,
  13         CONSTANT = 3
  14 };
  15
  16 // Does not properly account for overflow.
  17 inline unsigned div_round_up(unsigned val, unsigned div)
  18 {
  19         return (val + div - 1) / div;
  20 }
  21
  22 inline unsigned bytes_for_packed_bits(unsigned num, unsigned bit_width)
  23 {
  24         return div_round_up(num * bit_width, CHAR_BIT);
  25 }
  26
  27 constexpr uint32_t mask_for_bits(unsigned bit_width)
  28 {
  29         if (bit_width == 32) {
  30                 return 0xFFFFFFFF;
  31         } else {
  32                 return (1U << bit_width) - 1;
  33         }
  34 }
  35
  36 #endif  // !defined(_TURBOPFOR_COMMON_H)