/src/harfbuzz/src/hb-pool.hh

Source (jump to first uncovered line)
/*
 * Copyright © 2019  Facebook, Inc.
 *
 *  This is part of HarfBuzz, a text shaping library.
 *
 * Permission is hereby granted, without written agreement and without
 * license or royalty fees, to use, copy, modify, and distribute this
 * software and its documentation for any purpose, provided that the
 * above copyright notice and the following two paragraphs appear in
 * all copies of this software.
 *
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Facebook Author(s): Behdad Esfahbod
 */

#ifndef HB_POOL_HH
#define HB_POOL_HH

#include "hb.hh"

/* Memory pool for persistent allocation of small objects. */

template <typename T, unsigned ChunkLen = 32>
struct hb_pool_t
{
  hb_pool_t () : next (nullptr) {}
  ~hb_pool_t ()
  {
    next = nullptr;

    + hb_iter (chunks)
    | hb_apply (hb_free)
    ;
  }

  T* alloc ()
  {
    if (unlikely (!next))
    {
      if (unlikely (!chunks.alloc (chunks.length + 1))) return nullptr;
      chunk_t *chunk = (chunk_t *) hb_calloc (1, sizeof (chunk_t));
      if (unlikely (!chunk)) return nullptr;
      chunks.push (chunk);
      next = chunk->thread ();
    }

    T* obj = next;
    next = * ((T**) next);

    hb_memset (obj, 0, sizeof (T));

    return obj;
  }

  void release (T* obj)
  {
    * (T**) obj = next;
    next = obj;
  }

  private:

  static_assert (ChunkLen > 1, "");
  static_assert (sizeof (T) >= sizeof (void *), "");
  static_assert (alignof (T) % alignof (void *) == 0, "");

  struct chunk_t
  {
    T* thread ()
    {
      for (unsigned i = 0; i < ARRAY_LENGTH (arrayZ) - 1; i++)
  * (T**) &arrayZ[i] = &arrayZ[i + 1];

      * (T**) &arrayZ[ARRAY_LENGTH (arrayZ) - 1] = nullptr;

      return arrayZ;
    }

    T arrayZ[ChunkLen];
  };

  T* next;
  hb_vector_t<chunk_t *> chunks;
};


#endif /* HB_POOL_HH */

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright © 2019 Facebook, Inc.
3		*
4		* This is part of HarfBuzz, a text shaping library.
5		*
6		* Permission is hereby granted, without written agreement and without
7		* license or royalty fees, to use, copy, modify, and distribute this
8		* software and its documentation for any purpose, provided that the
9		* above copyright notice and the following two paragraphs appear in
10		* all copies of this software.
11		*
12		* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13		* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14		* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15		* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16		* DAMAGE.
17		*
18		* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19		* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20		* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21		* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22		* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23		*
24		* Facebook Author(s): Behdad Esfahbod
25		*/
26
27		#ifndef HB_POOL_HH
28		#define HB_POOL_HH
29
30		#include "hb.hh"
31
32		/* Memory pool for persistent allocation of small objects. */
33
34		template <typename T, unsigned ChunkLen = 32>
35		struct hb_pool_t
36		{
37	2.89k	hb_pool_t () : next (nullptr) {}
38		~hb_pool_t ()
39	2.89k	{
40	2.89k	next = nullptr;
41
42	2.89k	+ hb_iter (chunks)
43	2.89k	\| hb_apply (hb_free)
44	2.89k	;
45	2.89k	}
46
47		T* alloc ()
48	42.7k	{
49	42.7k	if (unlikely (!next))
50	3.63k	{
51	3.63k	if (unlikely (!chunks.alloc (chunks.length + 1))) return nullptr;
52	3.54k	chunk_t chunk = (chunk_t ) hb_calloc (1, sizeof (chunk_t));
53	3.54k	if (unlikely (!chunk)) return nullptr;
54	3.41k	chunks.push (chunk);
55	3.41k	next = chunk->thread ();
56	3.41k	}
57
58	42.5k	T* obj = next;
59	42.5k	next = * ((T**) next);
60
61	42.5k	hb_memset (obj, 0, sizeof (T));
62
63	42.5k	return obj;
64	42.7k	}
65
66		void release (T* obj)
67	0	{
68	0	* (T**) obj = next;
69	0	next = obj;
70	0	}
71
72		private:
73
74		static_assert (ChunkLen > 1, "");
75		static_assert (sizeof (T) >= sizeof (void *), "");
76		static_assert (alignof (T) % alignof (void *) == 0, "");
77
78		struct chunk_t
79		{
80		T* thread ()
81	3.41k	{
82	109k	for (unsigned i = 0; i < ARRAY_LENGTH (arrayZ) - 1; i++)
83	105k	* (T**) &arrayZ[i] = &arrayZ[i + 1];
84
85	3.41k	* (T**) &arrayZ[ARRAY_LENGTH (arrayZ) - 1] = nullptr;
86
87	3.41k	return arrayZ;
88	3.41k	}
89
90		T arrayZ[ChunkLen];
91		};
92
93		T* next;
94		hb_vector_t<chunk_t *> chunks;
95		};
96
97
98		#endif /* HB_POOL_HH */

Coverage Report

Created: 2024-08-21 15:15