/* Copyright (C) 1995, 1996 Aladdin Enterprises.  All rights reserved.
  
  This file is part of Aladdin Ghostscript.
  
  Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
  or distributor accepts any responsibility for the consequences of using it,
  or for whether it serves any particular purpose or works at all, unless he
  or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
  License (the "License") for full details.
  
  Every copy of Aladdin Ghostscript must include a copy of the License,
  normally in a plain ASCII text file named PUBLIC.  The License grants you
  the right to copy, modify and redistribute Aladdin Ghostscript, but only
  under certain conditions described in the License.  Among other things, the
  License requires that the copyright notice and this notice be preserved on
  all copies.
*/

/* gsbittab.c */
/* Tables for bit operations */
#include "stdpre.h"
#include "gsbittab.h"

/* ---------------- Byte processing tables ---------------- */

/*
 * byte_reverse_bits[B] = the byte B with the order of bits reversed.
 */
const byte byte_reverse_bits[256] = {
  bit_table_8(0, 1, 2, 4, 8, 0x10, 0x20, 0x40, 0x80)
};

/*
 * byte_right_mask[N] = a byte with N trailing 1s, 0 <= N <= 8.
 */
const byte byte_right_mask[9] = {
  0, 1, 3, 7, 0xf, 0x1f, 0x3f, 0x7f, 0xff
};

/*
 * byte_count_bits[B] = the number of 1-bits in a byte with value B.
 */
const byte byte_count_bits[256] = {
  bit_table_8(0, 1, 1, 1, 1, 1, 1, 1, 1)
};

/* ---------------- Scanning tables ---------------- */

/*
 * byte_bit_run_length_N[B], for 0 <= N <= 7, gives the length of the
 * run of 1-bits starting at bit N in a byte with value B,
 * numbering the bits in the byte as 01234567.  If the run includes
 * the low-order bit (i.e., might be continued into a following byte),
 * the run length is increased by 8.
 */

#define t8(n) n,n,n,n,n+1,n+1,n+2,n+11
#define r8(n) n,n,n,n,n,n,n,n
#define r16(n) r8(n),r8(n)
#define r32(n) r16(n),r16(n)
#define r64(n) r32(n),r32(n)
#define r128(n) r64(n),r64(n)
const byte byte_bit_run_length_0[256] = {
  r128(0), r64(1), r32(2), r16(3), r8(4), t8(5)
};
const byte far_data byte_bit_run_length_1[256] = {
  r64(0), r32(1), r16(2), r8(3), t8(4),
  r64(0), r32(1), r16(2), r8(3), t8(4)
};
const byte far_data byte_bit_run_length_2[256] = {
  r32(0), r16(1), r8(2), t8(3),
  r32(0), r16(1), r8(2), t8(3),
  r32(0), r16(1), r8(2), t8(3),
  r32(0), r16(1), r8(2), t8(3)
};
const byte far_data byte_bit_run_length_3[256] = {
  r16(0), r8(1), t8(2), r16(0), r8(1), t8(2),
  r16(0), r8(1), t8(2), r16(0), r8(1), t8(2),
  r16(0), r8(1), t8(2), r16(0), r8(1), t8(2),
  r16(0), r8(1), t8(2), r16(0), r8(1), t8(2)
};
const byte far_data byte_bit_run_length_4[256] = {
  r8(0), t8(1), r8(0), t8(1), r8(0), t8(1), r8(0), t8(1),
  r8(0), t8(1), r8(0), t8(1), r8(0), t8(1), r8(0), t8(1),
  r8(0), t8(1), r8(0), t8(1), r8(0), t8(1), r8(0), t8(1),
  r8(0), t8(1), r8(0), t8(1), r8(0), t8(1), r8(0), t8(1),
};
#define rr8(a,b,c,d,e,f,g,h)\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h,\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h,\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h,\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h,\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h,\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h,\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h,\
  a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h, a,b,c,d,e,f,g,h
const byte far_data byte_bit_run_length_5[256] = {
  rr8(0,0,0,0,1,1,2,11)
};
const byte far_data byte_bit_run_length_6[256] = {
  rr8(0,0,1,10,0,0,1,10)
};
const byte far_data byte_bit_run_length_7[256] = {
  rr8(0,9,0,9,0,9,0,9)
};

/* Pointer tables indexed by bit number. */

const byte *byte_bit_run_length[8] =
{ byte_bit_run_length_0, byte_bit_run_length_1,
  byte_bit_run_length_2, byte_bit_run_length_3,
  byte_bit_run_length_4, byte_bit_run_length_5,
  byte_bit_run_length_6, byte_bit_run_length_7
};
const byte *byte_bit_run_length_neg[8] =
{ byte_bit_run_length_0, byte_bit_run_length_7,
  byte_bit_run_length_6, byte_bit_run_length_5,
  byte_bit_run_length_4, byte_bit_run_length_3,
  byte_bit_run_length_2, byte_bit_run_length_1
};

/* Some C compilers insist on having executable code in every file.... */
void
gsbittab_dummy(void)
{
}
