integer_class.pkg

6端口寄存器IP内核VHDL源代码

-- +------------------------------------
-- | Library: VFP
-- | Designer: Tim Pagden
-- | Opened: 28 Dec 1997
-- +------------------------------------

package integer_class is
  
  -- extensions to std.standard.integer
  -- integer defined in std.standard

  type integer_array is array (natural range <>) of integer;
  -- integer subtypes
  subtype  positive_1_bit is integer range 0 to 1;
  subtype  positive_2_bit is integer range 0 to 3;
  subtype  positive_3_bit is integer range 0 to 7;
  subtype  positive_4_bit is integer range 0 to 15;
  subtype  positive_5_bit is integer range 0 to 31;
  subtype  positive_6_bit is integer range 0 to 63;
  subtype  positive_7_bit is integer range 0 to 127;
  subtype  positive_8_bit is integer range 0 to 255;
  subtype  positive_9_bit is integer range 0 to 511;
  subtype positive_10_bit is integer range 0 to 1023;
  subtype positive_11_bit is integer range 0 to 2047;
  subtype positive_12_bit is integer range 0 to 4095;
  subtype positive_13_bit is integer range 0 to 8191;
  subtype positive_14_bit is integer range 0 to 16383;
  subtype positive_15_bit is integer range 0 to 32767;
  subtype positive_16_bit is integer range 0 to 65535;
  subtype positive_17_bit is integer range 0 to 131071;
  subtype positive_18_bit is integer range 0 to 262143;
  subtype positive_19_bit is integer range 0 to 524287;
  subtype positive_20_bit is integer range 0 to 1048575;
  subtype positive_21_bit is integer range 0 to 2097151;
  subtype positive_22_bit is integer range 0 to 4194303;
  subtype positive_23_bit is integer range 0 to 8388607;
  subtype positive_24_bit is integer range 0 to 16777215;
  subtype positive_25_bit is integer range 0 to 33554431;
  subtype positive_26_bit is integer range 0 to 67108863;
  subtype positive_27_bit is integer range 0 to 134217727;
  subtype positive_28_bit is integer range 0 to 268435455;
  subtype positive_29_bit is integer range 0 to 536870911;
  subtype positive_30_bit is integer range 0 to 1073741823;
  subtype positive_31_bit is integer range 0 to 2147483647;
  
  subtype  integer_1_bit is integer range -1 to 0;
  subtype  integer_2_bit is integer range -2 to 1;
  subtype  integer_3_bit is integer range -4 to 3;
  subtype  integer_4_bit is integer range -8 to 7;
  subtype  integer_5_bit is integer range -16 to 15;
  subtype  integer_6_bit is integer range -32 to 31;
  subtype  integer_7_bit is integer range -64 to 63;
  subtype  integer_8_bit is integer range -128 to 127;
  subtype  integer_9_bit is integer range -256 to 255;
  subtype integer_10_bit is integer range -512 to 511;
  subtype integer_11_bit is integer range -1024 to 1023;
  subtype integer_12_bit is integer range -2048 to 2047;
  subtype integer_13_bit is integer range -4096 to 4095;
  subtype integer_14_bit is integer range -8192 to 8191;
  subtype integer_15_bit is integer range -16384 to 16383;
  subtype integer_16_bit is integer range -32768 to 32767;
  subtype integer_17_bit is integer range -65536 to 65535;
  subtype integer_18_bit is integer range -131072 to 131071;
  subtype integer_19_bit is integer range -262144 to 262143;
  subtype integer_20_bit is integer range -524288 to 524287;
  subtype integer_21_bit is integer range -1048576 to 1048575;
  subtype integer_22_bit is integer range -2097152 to 2097151;
  subtype integer_23_bit is integer range -4194304 to 4194303;
  subtype integer_24_bit is integer range -8388608 to 8388607;
  subtype integer_25_bit is integer range -16777216 to 16777215;
  subtype integer_26_bit is integer range -33554432 to 33554431;
  subtype integer_27_bit is integer range -67108864 to 67108863;
  subtype integer_28_bit is integer range -134217728 to 134217727;
  subtype integer_29_bit is integer range -268435456 to 268435455;
  subtype integer_30_bit is integer range -536870912 to 536870911;
  subtype integer_31_bit is integer range -1073741824 to 1073741823;
  
  -- arithmetic operators
  -- defined in std.standard

  -- general purpose functions
  function integer_wordlength (a: integer) return integer;  -- 25.11.92
  function integer_charlength (a: integer) return integer;  -- 29.12.97
  function next_greater_binary_power_minus_1 (a: integer) return integer;  -- 14.02.93
  
  -- hardware functions
  -- none yet defined

  -- mathematical functions
  function is_factor_of_32 (a: integer) return boolean; -- 15.11.95
  function is_power_of_2 (a: integer) return boolean;   -- 15.11.95
  function log_2 (a: integer) return integer;           -- 15.11.95

end integer_class;