glib/cmph/select.c
Colin Walters 6178293a83 Import CMPH 1.0
This will be used for typelib indexing.  See README-CMPH-IMPORT.txt
for more information.
2010-12-03 16:03:31 -05:00

338 lines
9.6 KiB
C

#include<stdlib.h>
#include<stdio.h>
#include <assert.h>
#include <string.h>
#include <limits.h>
#include "select_lookup_tables.h"
#include "select.h"
//#define DEBUG
#include "debug.h"
#ifndef STEP_SELECT_TABLE
#define STEP_SELECT_TABLE 128
#endif
#ifndef NBITS_STEP_SELECT_TABLE
#define NBITS_STEP_SELECT_TABLE 7
#endif
#ifndef MASK_STEP_SELECT_TABLE
#define MASK_STEP_SELECT_TABLE 0x7f // 0x7f = 127
#endif
static inline void select_insert_0(cmph_uint32 * buffer)
{
(*buffer) >>= 1;
};
static inline void select_insert_1(cmph_uint32 * buffer)
{
(*buffer) >>= 1;
(*buffer) |= 0x80000000;
};
void select_init(select_t * sel)
{
sel->n = 0;
sel->m = 0;
sel->bits_vec = 0;
sel->select_table = 0;
};
cmph_uint32 select_get_space_usage(select_t * sel)
{
register cmph_uint32 nbits;
register cmph_uint32 vec_size;
register cmph_uint32 sel_table_size;
register cmph_uint32 space_usage;
nbits = sel->n + sel->m;
vec_size = (nbits + 31) >> 5;
sel_table_size = (sel->n >> NBITS_STEP_SELECT_TABLE) + 1; // (sel->n >> NBITS_STEP_SELECT_TABLE) = (sel->n/STEP_SELECT_TABLE)
space_usage = 2 * sizeof(cmph_uint32) * 8; // n and m
space_usage += vec_size * (cmph_uint32) sizeof(cmph_uint32) * 8;
space_usage += sel_table_size * (cmph_uint32)sizeof(cmph_uint32) * 8;
return space_usage;
}
void select_destroy(select_t * sel)
{
free(sel->bits_vec);
free(sel->select_table);
sel->bits_vec = 0;
sel->select_table = 0;
};
static inline void select_generate_sel_table(select_t * sel)
{
register cmph_uint8 * bits_table = (cmph_uint8 *)sel->bits_vec;
register cmph_uint32 part_sum, old_part_sum;
register cmph_uint32 vec_idx, one_idx, sel_table_idx;
part_sum = vec_idx = one_idx = sel_table_idx = 0;
for(;;)
{
// FABIANO: Should'n it be one_idx >= sel->n
if(one_idx >= sel->n)
break;
do
{
old_part_sum = part_sum;
part_sum += rank_lookup_table[bits_table[vec_idx]];
vec_idx++;
} while (part_sum <= one_idx);
sel->select_table[sel_table_idx] = select_lookup_table[bits_table[vec_idx - 1]][one_idx - old_part_sum] + ((vec_idx - 1) << 3); // ((vec_idx - 1) << 3) = ((vec_idx - 1) * 8)
one_idx += STEP_SELECT_TABLE ;
sel_table_idx++;
};
};
void select_generate(select_t * sel, cmph_uint32 * keys_vec, cmph_uint32 n, cmph_uint32 m)
{
register cmph_uint32 i, j, idx;
cmph_uint32 buffer = 0;
register cmph_uint32 nbits;
register cmph_uint32 vec_size;
register cmph_uint32 sel_table_size;
sel->n = n;
sel->m = m; // n values in the range [0,m-1]
nbits = sel->n + sel->m;
vec_size = (nbits + 31) >> 5; // (nbits + 31) >> 5 = (nbits + 31)/32
sel_table_size = (sel->n >> NBITS_STEP_SELECT_TABLE) + 1; // (sel->n >> NBITS_STEP_SELECT_TABLE) = (sel->n/STEP_SELECT_TABLE)
if(sel->bits_vec)
{
free(sel->bits_vec);
}
sel->bits_vec = (cmph_uint32 *)calloc(vec_size, sizeof(cmph_uint32));
if(sel->select_table)
{
free(sel->select_table);
}
sel->select_table = (cmph_uint32 *)calloc(sel_table_size, sizeof(cmph_uint32));
idx = i = j = 0;
for(;;)
{
while(keys_vec[j]==i)
{
select_insert_1(&buffer);
idx++;
if((idx & 0x1f) == 0 ) // (idx & 0x1f) = idx % 32
sel->bits_vec[(idx >> 5) - 1] = buffer; // (idx >> 5) = idx/32
j++;
if(j == sel->n)
goto loop_end;
//assert(keys_vec[j] < keys_vec[j-1]);
}
if(i == sel->m)
break;
while(keys_vec[j] > i)
{
select_insert_0(&buffer);
idx++;
if((idx & 0x1f) == 0 ) // (idx & 0x1f) = idx % 32
sel->bits_vec[(idx >> 5) - 1] = buffer; // (idx >> 5) = idx/32
i++;
};
};
loop_end:
if((idx & 0x1f) != 0 ) // (idx & 0x1f) = idx % 32
{
buffer >>= 32 - (idx & 0x1f);
sel->bits_vec[ (idx - 1) >> 5 ] = buffer;
};
select_generate_sel_table(sel);
};
static inline cmph_uint32 _select_query(cmph_uint8 * bits_table, cmph_uint32 * select_table, cmph_uint32 one_idx)
{
register cmph_uint32 vec_bit_idx ,vec_byte_idx;
register cmph_uint32 part_sum, old_part_sum;
vec_bit_idx = select_table[one_idx >> NBITS_STEP_SELECT_TABLE]; // one_idx >> NBITS_STEP_SELECT_TABLE = one_idx/STEP_SELECT_TABLE
vec_byte_idx = vec_bit_idx >> 3; // vec_bit_idx / 8
one_idx &= MASK_STEP_SELECT_TABLE; // one_idx %= STEP_SELECT_TABLE == one_idx &= MASK_STEP_SELECT_TABLE
one_idx += rank_lookup_table[bits_table[vec_byte_idx] & ((1 << (vec_bit_idx & 0x7)) - 1)];
part_sum = 0;
do
{
old_part_sum = part_sum;
part_sum += rank_lookup_table[bits_table[vec_byte_idx]];
vec_byte_idx++;
}while (part_sum <= one_idx);
return select_lookup_table[bits_table[vec_byte_idx - 1]][one_idx - old_part_sum] + ((vec_byte_idx-1) << 3);
}
cmph_uint32 select_query(select_t * sel, cmph_uint32 one_idx)
{
return _select_query((cmph_uint8 *)sel->bits_vec, sel->select_table, one_idx);
};
static inline cmph_uint32 _select_next_query(cmph_uint8 * bits_table, cmph_uint32 vec_bit_idx)
{
register cmph_uint32 vec_byte_idx, one_idx;
register cmph_uint32 part_sum, old_part_sum;
vec_byte_idx = vec_bit_idx >> 3;
one_idx = rank_lookup_table[bits_table[vec_byte_idx] & ((1U << (vec_bit_idx & 0x7)) - 1U)] + 1U;
part_sum = 0;
do
{
old_part_sum = part_sum;
part_sum += rank_lookup_table[bits_table[vec_byte_idx]];
vec_byte_idx++;
}while (part_sum <= one_idx);
return select_lookup_table[bits_table[(vec_byte_idx - 1)]][(one_idx - old_part_sum)] + ((vec_byte_idx - 1) << 3);
}
cmph_uint32 select_next_query(select_t * sel, cmph_uint32 vec_bit_idx)
{
return _select_next_query((cmph_uint8 *)sel->bits_vec, vec_bit_idx);
};
void select_dump(select_t *sel, char **buf, cmph_uint32 *buflen)
{
register cmph_uint32 nbits = sel->n + sel->m;
register cmph_uint32 vec_size = ((nbits + 31) >> 5) * (cmph_uint32)sizeof(cmph_uint32); // (nbits + 31) >> 5 = (nbits + 31)/32
register cmph_uint32 sel_table_size = ((sel->n >> NBITS_STEP_SELECT_TABLE) + 1) * (cmph_uint32)sizeof(cmph_uint32); // (sel->n >> NBITS_STEP_SELECT_TABLE) = (sel->n/STEP_SELECT_TABLE)
register cmph_uint32 pos = 0;
*buflen = 2*(cmph_uint32)sizeof(cmph_uint32) + vec_size + sel_table_size;
*buf = (char *)calloc(*buflen, sizeof(char));
if (!*buf)
{
*buflen = UINT_MAX;
return;
}
memcpy(*buf, &(sel->n), sizeof(cmph_uint32));
pos += (cmph_uint32)sizeof(cmph_uint32);
memcpy(*buf + pos, &(sel->m), sizeof(cmph_uint32));
pos += (cmph_uint32)sizeof(cmph_uint32);
memcpy(*buf + pos, sel->bits_vec, vec_size);
pos += vec_size;
memcpy(*buf + pos, sel->select_table, sel_table_size);
DEBUGP("Dumped select structure with size %u bytes\n", *buflen);
}
void select_load(select_t * sel, const char *buf, cmph_uint32 buflen)
{
register cmph_uint32 pos = 0;
register cmph_uint32 nbits = 0;
register cmph_uint32 vec_size = 0;
register cmph_uint32 sel_table_size = 0;
memcpy(&(sel->n), buf, sizeof(cmph_uint32));
pos += (cmph_uint32)sizeof(cmph_uint32);
memcpy(&(sel->m), buf + pos, sizeof(cmph_uint32));
pos += (cmph_uint32)sizeof(cmph_uint32);
nbits = sel->n + sel->m;
vec_size = ((nbits + 31) >> 5) * (cmph_uint32)sizeof(cmph_uint32); // (nbits + 31) >> 5 = (nbits + 31)/32
sel_table_size = ((sel->n >> NBITS_STEP_SELECT_TABLE) + 1) * (cmph_uint32)sizeof(cmph_uint32); // (sel->n >> NBITS_STEP_SELECT_TABLE) = (sel->n/STEP_SELECT_TABLE)
if(sel->bits_vec)
{
free(sel->bits_vec);
}
sel->bits_vec = (cmph_uint32 *)calloc(vec_size/sizeof(cmph_uint32), sizeof(cmph_uint32));
if(sel->select_table)
{
free(sel->select_table);
}
sel->select_table = (cmph_uint32 *)calloc(sel_table_size/sizeof(cmph_uint32), sizeof(cmph_uint32));
memcpy(sel->bits_vec, buf + pos, vec_size);
pos += vec_size;
memcpy(sel->select_table, buf + pos, sel_table_size);
DEBUGP("Loaded select structure with size %u bytes\n", buflen);
}
/** \fn void select_pack(select_t *sel, void *sel_packed);
* \brief Support the ability to pack a select structure function into a preallocated contiguous memory space pointed by sel_packed.
* \param sel points to the select structure
* \param sel_packed pointer to the contiguous memory area used to store the select structure. The size of sel_packed must be at least @see select_packed_size
*/
void select_pack(select_t *sel, void *sel_packed)
{
if (sel && sel_packed)
{
char *buf = NULL;
cmph_uint32 buflen = 0;
select_dump(sel, &buf, &buflen);
memcpy(sel_packed, buf, buflen);
free(buf);
}
}
/** \fn cmph_uint32 select_packed_size(select_t *sel);
* \brief Return the amount of space needed to pack a select structure.
* \return the size of the packed select structure or zero for failures
*/
cmph_uint32 select_packed_size(select_t *sel)
{
register cmph_uint32 nbits = sel->n + sel->m;
register cmph_uint32 vec_size = ((nbits + 31) >> 5) * (cmph_uint32)sizeof(cmph_uint32); // (nbits + 31) >> 5 = (nbits + 31)/32
register cmph_uint32 sel_table_size = ((sel->n >> NBITS_STEP_SELECT_TABLE) + 1) * (cmph_uint32)sizeof(cmph_uint32); // (sel->n >> NBITS_STEP_SELECT_TABLE) = (sel->n/STEP_SELECT_TABLE)
return 2*(cmph_uint32)sizeof(cmph_uint32) + vec_size + sel_table_size;
}
cmph_uint32 select_query_packed(void * sel_packed, cmph_uint32 one_idx)
{
register cmph_uint32 *ptr = (cmph_uint32 *)sel_packed;
register cmph_uint32 n = *ptr++;
register cmph_uint32 m = *ptr++;
register cmph_uint32 nbits = n + m;
register cmph_uint32 vec_size = (nbits + 31) >> 5; // (nbits + 31) >> 5 = (nbits + 31)/32
register cmph_uint8 * bits_vec = (cmph_uint8 *)ptr;
register cmph_uint32 * select_table = ptr + vec_size;
return _select_query(bits_vec, select_table, one_idx);
}
cmph_uint32 select_next_query_packed(void * sel_packed, cmph_uint32 vec_bit_idx)
{
register cmph_uint8 * bits_vec = (cmph_uint8 *)sel_packed;
bits_vec += 8; // skipping n and m
return _select_next_query(bits_vec, vec_bit_idx);
}