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/*
* Copyright 2012-2015 Samy Al Bahra.
* Copyright 2012-2014 AppNexus, Inc.
* Copyright 2014 Paul Khuong.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef CK_BITMAP_H
#define CK_BITMAP_H
#include <ck_cc.h>
#include <ck_limits.h>
#include <ck_pr.h>
#include <ck_stdint.h>
#include <ck_stdbool.h>
#include <ck_stddef.h>
#include <ck_stdbool.h>
#include <ck_stddef.h>
#include <ck_string.h>
#if !defined(CK_F_PR_LOAD_UINT) || !defined(CK_F_PR_STORE_UINT) || \
!defined(CK_F_PR_AND_UINT) || !defined(CK_F_PR_OR_UINT) || \
!defined(CK_F_CC_CTZ)
#error "ck_bitmap is not supported on your platform."
#endif
#define CK_BITMAP_BLOCK (sizeof(unsigned int) * CHAR_BIT)
#define CK_BITMAP_OFFSET(i) ((i) % CK_BITMAP_BLOCK)
#define CK_BITMAP_BIT(i) (1U << CK_BITMAP_OFFSET(i))
#define CK_BITMAP_PTR(x, i) ((x) + ((i) / CK_BITMAP_BLOCK))
#define CK_BITMAP_BLOCKS(n) (((n) + CK_BITMAP_BLOCK - 1) / CK_BITMAP_BLOCK)
#define CK_BITMAP_INSTANCE(n_entries) \
union { \
struct { \
unsigned int n_bits; \
unsigned int map[CK_BITMAP_BLOCKS(n_entries)]; \
} content; \
struct ck_bitmap bitmap; \
}
#define CK_BITMAP_ITERATOR_INIT(a, b) \
ck_bitmap_iterator_init((a), &(b)->bitmap)
#define CK_BITMAP_INIT(a, b, c) \
ck_bitmap_init(&(a)->bitmap, (b), (c))
#define CK_BITMAP_NEXT(a, b, c) \
ck_bitmap_next(&(a)->bitmap, (b), (c))
#define CK_BITMAP_SET(a, b) \
ck_bitmap_set(&(a)->bitmap, (b))
#define CK_BITMAP_BTS(a, b) \
ck_bitmap_bts(&(a)->bitmap, (b))
#define CK_BITMAP_RESET(a, b) \
ck_bitmap_reset(&(a)->bitmap, (b))
#define CK_BITMAP_TEST(a, b) \
ck_bitmap_test(&(a)->bitmap, (b))
#define CK_BITMAP_UNION(a, b) \
ck_bitmap_union(&(a)->bitmap, &(b)->bitmap)
#define CK_BITMAP_INTERSECTION(a, b) \
ck_bitmap_intersection(&(a)->bitmap, &(b)->bitmap)
#define CK_BITMAP_INTERSECTION_NEGATE(a, b) \
ck_bitmap_intersection_negate(&(a)->bitmap, &(b)->bitmap)
#define CK_BITMAP_CLEAR(a) \
ck_bitmap_clear(&(a)->bitmap)
#define CK_BITMAP_EMPTY(a, b) \
ck_bitmap_empty(&(a)->bitmap, b)
#define CK_BITMAP_FULL(a, b) \
ck_bitmap_full(&(a)->bitmap, b)
#define CK_BITMAP_COUNT(a, b) \
ck_bitmap_count(&(a)->bitmap, b)
#define CK_BITMAP_COUNT_INTERSECT(a, b, c) \
ck_bitmap_count_intersect(&(a)->bitmap, b, c)
#define CK_BITMAP_BITS(a) \
ck_bitmap_bits(&(a)->bitmap)
#define CK_BITMAP_BUFFER(a) \
ck_bitmap_buffer(&(a)->bitmap)
#define CK_BITMAP(a) \
(&(a)->bitmap)
struct ck_bitmap {
unsigned int n_bits;
unsigned int map[];
};
typedef struct ck_bitmap ck_bitmap_t;
struct ck_bitmap_iterator {
unsigned int cache;
unsigned int n_block;
unsigned int n_limit;
};
typedef struct ck_bitmap_iterator ck_bitmap_iterator_t;
CK_CC_INLINE static unsigned int
ck_bitmap_base(unsigned int n_bits)
{
return CK_BITMAP_BLOCKS(n_bits) * sizeof(unsigned int);
}
/*
* Returns the required number of bytes for a ck_bitmap_t object supporting the
* specified number of bits.
*/
CK_CC_INLINE static unsigned int
ck_bitmap_size(unsigned int n_bits)
{
return ck_bitmap_base(n_bits) + sizeof(struct ck_bitmap);
}
/*
* Returns total number of bits in specified bitmap.
*/
CK_CC_INLINE static unsigned int
ck_bitmap_bits(const struct ck_bitmap *bitmap)
{
return bitmap->n_bits;
}
/*
* Returns a pointer to the bit buffer associated
* with the specified bitmap.
*/
CK_CC_INLINE static void *
ck_bitmap_buffer(struct ck_bitmap *bitmap)
{
return bitmap->map;
}
/*
* Sets the bit at the offset specified in the second argument.
*/
CK_CC_INLINE static void
ck_bitmap_set(struct ck_bitmap *bitmap, unsigned int n)
{
ck_pr_or_uint(CK_BITMAP_PTR(bitmap->map, n), CK_BITMAP_BIT(n));
return;
}
/*
* Performs a test-and-set operation at the offset specified in the
* second argument.
* Returns true if the bit at the specified offset was already set,
* false otherwise.
*/
CK_CC_INLINE static bool
ck_bitmap_bts(struct ck_bitmap *bitmap, unsigned int n)
{
return ck_pr_bts_uint(CK_BITMAP_PTR(bitmap->map, n),
CK_BITMAP_OFFSET(n));
}
/*
* Resets the bit at the offset specified in the second argument.
*/
CK_CC_INLINE static void
ck_bitmap_reset(struct ck_bitmap *bitmap, unsigned int n)
{
ck_pr_and_uint(CK_BITMAP_PTR(bitmap->map, n), ~CK_BITMAP_BIT(n));
return;
}
/*
* Determines whether the bit at offset specified in the
* second argument is set.
*/
CK_CC_INLINE static bool
ck_bitmap_test(const struct ck_bitmap *bitmap, unsigned int n)
{
unsigned int block;
block = ck_pr_load_uint(CK_BITMAP_PTR(bitmap->map, n));
return block & CK_BITMAP_BIT(n);
}
/*
* Combines bits from second bitmap into the first bitmap. This is not a
* linearized operation with respect to the complete bitmap.
*/
CK_CC_INLINE static void
ck_bitmap_union(struct ck_bitmap *dst, const struct ck_bitmap *src)
{
unsigned int n;
unsigned int n_buckets = dst->n_bits;
if (src->n_bits < dst->n_bits)
n_buckets = src->n_bits;
n_buckets = CK_BITMAP_BLOCKS(n_buckets);
for (n = 0; n < n_buckets; n++) {
ck_pr_or_uint(&dst->map[n],
ck_pr_load_uint(&src->map[n]));
}
return;
}
/*
* Intersects bits from second bitmap into the first bitmap. This is
* not a linearized operation with respect to the complete bitmap.
* Any trailing bit in dst is cleared.
*/
CK_CC_INLINE static void
ck_bitmap_intersection(struct ck_bitmap *dst, const struct ck_bitmap *src)
{
unsigned int n;
unsigned int n_buckets = dst->n_bits;
unsigned int n_intersect = n_buckets;
if (src->n_bits < n_intersect)
n_intersect = src->n_bits;
n_buckets = CK_BITMAP_BLOCKS(n_buckets);
n_intersect = CK_BITMAP_BLOCKS(n_intersect);
for (n = 0; n < n_intersect; n++) {
ck_pr_and_uint(&dst->map[n],
ck_pr_load_uint(&src->map[n]));
}
for (; n < n_buckets; n++)
ck_pr_store_uint(&dst->map[n], 0);
return;
}
/*
* Intersects the complement of bits from second bitmap into the first
* bitmap. This is not a linearized operation with respect to the
* complete bitmap. Any trailing bit in dst is left as is.
*/
CK_CC_INLINE static void
ck_bitmap_intersection_negate(struct ck_bitmap *dst,
const struct ck_bitmap *src)
{
unsigned int n;
unsigned int n_intersect = dst->n_bits;
if (src->n_bits < n_intersect)
n_intersect = src->n_bits;
n_intersect = CK_BITMAP_BLOCKS(n_intersect);
for (n = 0; n < n_intersect; n++) {
ck_pr_and_uint(&dst->map[n],
(~ck_pr_load_uint(&src->map[n])));
}
return;
}
/*
* Resets all bits in the provided bitmap. This is not a linearized
* operation in ck_bitmap.
*/
CK_CC_INLINE static void
ck_bitmap_clear(struct ck_bitmap *bitmap)
{
unsigned int i;
unsigned int n_buckets = ck_bitmap_base(bitmap->n_bits) /
sizeof(unsigned int);
for (i = 0; i < n_buckets; i++)
ck_pr_store_uint(&bitmap->map[i], 0);
return;
}
/*
* Returns true if the first limit bits in bitmap are cleared. If
* limit is greater than the bitmap size, limit is truncated to that
* size.
*/
CK_CC_INLINE static bool
ck_bitmap_empty(const ck_bitmap_t *bitmap, unsigned int limit)
{
unsigned int i, words, slop;
if (limit > bitmap->n_bits)
limit = bitmap->n_bits;
words = limit / CK_BITMAP_BLOCK;
slop = limit % CK_BITMAP_BLOCK;
for (i = 0; i < words; i++) {
if (ck_pr_load_uint(&bitmap->map[i]) != 0) {
return false;
}
}
if (slop > 0) {
unsigned int word;
word = ck_pr_load_uint(&bitmap->map[i]);
if ((word & ((1U << slop) - 1)) != 0)
return false;
}
return true;
}
/*
* Returns true if the first limit bits in bitmap are set. If limit
* is greater than the bitmap size, limit is truncated to that size.
*/
CK_CC_UNUSED static bool
ck_bitmap_full(const ck_bitmap_t *bitmap, unsigned int limit)
{
unsigned int i, slop, words;
if (limit > bitmap->n_bits) {
limit = bitmap->n_bits;
}
words = limit / CK_BITMAP_BLOCK;
slop = limit % CK_BITMAP_BLOCK;
for (i = 0; i < words; i++) {
if (ck_pr_load_uint(&bitmap->map[i]) != -1U)
return false;
}
if (slop > 0) {
unsigned int word;
word = ~ck_pr_load_uint(&bitmap->map[i]);
if ((word & ((1U << slop) - 1)) != 0)
return false;
}
return true;
}
/*
* Returns the number of set bit in bitmap, upto (and excluding)
* limit. If limit is greater than the bitmap size, it is truncated
* to that size.
*/
CK_CC_INLINE static unsigned int
ck_bitmap_count(const ck_bitmap_t *bitmap, unsigned int limit)
{
unsigned int count, i, slop, words;
if (limit > bitmap->n_bits)
limit = bitmap->n_bits;
words = limit / CK_BITMAP_BLOCK;
slop = limit % CK_BITMAP_BLOCK;
for (i = 0, count = 0; i < words; i++)
count += ck_cc_popcount(ck_pr_load_uint(&bitmap->map[i]));
if (slop > 0) {
unsigned int word;
word = ck_pr_load_uint(&bitmap->map[i]);
count += ck_cc_popcount(word & ((1U << slop) - 1));
}
return count;
}
/*
* Returns the number of set bit in the intersection of two bitmaps,
* upto (and excluding) limit. If limit is greater than either bitmap
* size, it is truncated to the smallest.
*/
CK_CC_INLINE static unsigned int
ck_bitmap_count_intersect(const ck_bitmap_t *x, const ck_bitmap_t *y,
unsigned int limit)
{
unsigned int count, i, slop, words;
if (limit > x->n_bits)
limit = x->n_bits;
if (limit > y->n_bits)
limit = y->n_bits;
words = limit / CK_BITMAP_BLOCK;
slop = limit % CK_BITMAP_BLOCK;
for (i = 0, count = 0; i < words; i++) {
unsigned int xi, yi;
xi = ck_pr_load_uint(&x->map[i]);
yi = ck_pr_load_uint(&y->map[i]);
count += ck_cc_popcount(xi & yi);
}
if (slop > 0) {
unsigned int word, xi, yi;
xi = ck_pr_load_uint(&x->map[i]);
yi = ck_pr_load_uint(&y->map[i]);
word = xi & yi;
count += ck_cc_popcount(word & ((1U << slop) - 1));
}
return count;
}
/*
* Initializes a ck_bitmap pointing to a region of memory with
* ck_bitmap_size(n_bits) bytes. Third argument determines whether
* default bit value is 1 (true) or 0 (false).
*/
CK_CC_INLINE static void
ck_bitmap_init(struct ck_bitmap *bitmap,
unsigned int n_bits,
bool set)
{
unsigned int base = ck_bitmap_base(n_bits);
bitmap->n_bits = n_bits;
memset(bitmap->map, -(int)set, base);
if (set == true) {
unsigned int b = n_bits % CK_BITMAP_BLOCK;
if (b == 0)
return;
*CK_BITMAP_PTR(bitmap->map, n_bits - 1) &= (1U << b) - 1U;
}
return;
}
/*
* Initialize iterator for use with provided bitmap.
*/
CK_CC_INLINE static void
ck_bitmap_iterator_init(struct ck_bitmap_iterator *i,
const struct ck_bitmap *bitmap)
{
i->n_block = 0;
i->n_limit = CK_BITMAP_BLOCKS(bitmap->n_bits);
if (i->n_limit > 0) {
i->cache = ck_pr_load_uint(&bitmap->map[0]);
} else {
i->cache = 0;
}
return;
}
/*
* Iterate to next bit.
*/
CK_CC_INLINE static bool
ck_bitmap_next(const struct ck_bitmap *bitmap,
struct ck_bitmap_iterator *i,
unsigned int *bit)
{
unsigned int cache = i->cache;
unsigned int n_block = i->n_block;
unsigned int n_limit = i->n_limit;
if (cache == 0) {
if (n_block >= n_limit)
return false;
for (n_block++; n_block < n_limit; n_block++) {
cache = ck_pr_load_uint(&bitmap->map[n_block]);
if (cache != 0)
goto non_zero;
}
i->cache = 0;
i->n_block = n_block;
return false;
}
non_zero:
*bit = CK_BITMAP_BLOCK * n_block + ck_cc_ctz(cache);
i->cache = cache & (cache - 1);
i->n_block = n_block;
return true;
}
#endif /* CK_BITMAP_H */