From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- gfx/harfbuzz/src/hb-pool.hh | 107 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 107 insertions(+) create mode 100644 gfx/harfbuzz/src/hb-pool.hh (limited to 'gfx/harfbuzz/src/hb-pool.hh') diff --git a/gfx/harfbuzz/src/hb-pool.hh b/gfx/harfbuzz/src/hb-pool.hh new file mode 100644 index 0000000000..d6eb778f5d --- /dev/null +++ b/gfx/harfbuzz/src/hb-pool.hh @@ -0,0 +1,107 @@ +/* + * 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. + * + * Some AI musings on this, not necessarily true: + * + * This is a very simple implementation, but it's good enough for our + * purposes. It's not thread-safe. It's not very fast. It's not + * very memory efficient. It's not very cache efficient. It's not + * very anything efficient. But it's simple and it works. And it's + * good enough for our purposes. If you need something more + * sophisticated, use a real allocator. Or use a real language. */ + +template +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 chunks; +}; + + +#endif /* HB_POOL_HH */ -- cgit v1.2.3