diff options
Diffstat (limited to 'BaseTools/Source/C/BrotliCompress/enc/hash_longest_match_quickly_inc.h')
| -rw-r--r-- | BaseTools/Source/C/BrotliCompress/enc/hash_longest_match_quickly_inc.h | 230 |
1 files changed, 0 insertions, 230 deletions
diff --git a/BaseTools/Source/C/BrotliCompress/enc/hash_longest_match_quickly_inc.h b/BaseTools/Source/C/BrotliCompress/enc/hash_longest_match_quickly_inc.h deleted file mode 100644 index 49e6795f5a..0000000000 --- a/BaseTools/Source/C/BrotliCompress/enc/hash_longest_match_quickly_inc.h +++ /dev/null @@ -1,230 +0,0 @@ -/* NOLINT(build/header_guard) */
-/* Copyright 2010 Google Inc. All Rights Reserved.
-
- Distributed under MIT license.
- See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
-*/
-
-/* template parameters: FN, BUCKET_BITS, BUCKET_SWEEP, USE_DICTIONARY */
-
-#define HashLongestMatchQuickly HASHER()
-
-#define BUCKET_SIZE (1 << BUCKET_BITS)
-
-#define HASH_MAP_SIZE (4 << BUCKET_BITS)
-
-static BROTLI_INLINE size_t FN(HashTypeLength)(void) { return 8; }
-static BROTLI_INLINE size_t FN(StoreLookahead)(void) { return 8; }
-
-/* HashBytes is the function that chooses the bucket to place
- the address in. The HashLongestMatch and HashLongestMatchQuickly
- classes have separate, different implementations of hashing. */
-static uint32_t FN(HashBytes)(const uint8_t *data) {
- /* Computing a hash based on 5 bytes works much better for
- qualities 1 and 3, where the next hash value is likely to replace */
- uint64_t h = (BROTLI_UNALIGNED_LOAD64(data) << 24) * kHashMul32;
- /* The higher bits contain more mixture from the multiplication,
- so we take our results from there. */
- return (uint32_t)(h >> (64 - BUCKET_BITS));
-}
-
-/* A (forgetful) hash table to the data seen by the compressor, to
- help create backward references to previous data.
-
- This is a hash map of fixed size (BUCKET_SIZE). Starting from the
- given index, BUCKET_SWEEP buckets are used to store values of a key. */
-typedef struct HashLongestMatchQuickly {
- uint32_t buckets_[BUCKET_SIZE + BUCKET_SWEEP];
- /* True if buckets_ array needs to be initialized. */
- BROTLI_BOOL is_dirty_;
- DictionarySearchStatictics dict_search_stats_;
-} HashLongestMatchQuickly;
-
-static void FN(Reset)(HashLongestMatchQuickly* self) {
- self->is_dirty_ = BROTLI_TRUE;
- DictionarySearchStaticticsReset(&self->dict_search_stats_);
-}
-
-static void FN(InitEmpty)(HashLongestMatchQuickly* self) {
- if (self->is_dirty_) {
- /* It is not strictly necessary to fill this buffer here, but
- not filling will make the results of the compression stochastic
- (but correct). This is because random data would cause the
- system to find accidentally good backward references here and there. */
- memset(&self->buckets_[0], 0, sizeof(self->buckets_));
- self->is_dirty_ = BROTLI_FALSE;
- }
-}
-
-static void FN(InitForData)(HashLongestMatchQuickly* self, const uint8_t* data,
- size_t num) {
- size_t i;
- for (i = 0; i < num; ++i) {
- const uint32_t key = FN(HashBytes)(&data[i]);
- memset(&self->buckets_[key], 0, BUCKET_SWEEP * sizeof(self->buckets_[0]));
- }
- if (num != 0) {
- self->is_dirty_ = BROTLI_FALSE;
- }
-}
-
-static void FN(Init)(
- MemoryManager* m, HashLongestMatchQuickly* self, const uint8_t* data,
- const BrotliEncoderParams* params, size_t position, size_t bytes,
- BROTLI_BOOL is_last) {
- /* Choose which init method is faster.
- Init() is about 100 times faster than InitForData(). */
- const size_t kMaxBytesForPartialHashInit = HASH_MAP_SIZE >> 7;
- BROTLI_UNUSED(m);
- BROTLI_UNUSED(params);
- if (position == 0 && is_last && bytes <= kMaxBytesForPartialHashInit) {
- FN(InitForData)(self, data, bytes);
- } else {
- FN(InitEmpty)(self);
- }
-}
-
-/* Look at 5 bytes at &data[ix & mask].
- Compute a hash from these, and store the value somewhere within
- [ix .. ix+3]. */
-static BROTLI_INLINE void FN(Store)(HashLongestMatchQuickly* self,
- const uint8_t *data, const size_t mask, const size_t ix) {
- const uint32_t key = FN(HashBytes)(&data[ix & mask]);
- /* Wiggle the value with the bucket sweep range. */
- const uint32_t off = (ix >> 3) % BUCKET_SWEEP;
- self->buckets_[key + off] = (uint32_t)ix;
-}
-
-static BROTLI_INLINE void FN(StoreRange)(HashLongestMatchQuickly* self,
- const uint8_t *data, const size_t mask, const size_t ix_start,
- const size_t ix_end) {
- size_t i;
- for (i = ix_start; i < ix_end; ++i) {
- FN(Store)(self, data, mask, i);
- }
-}
-
-static BROTLI_INLINE void FN(StitchToPreviousBlock)(
- HashLongestMatchQuickly* self, size_t num_bytes, size_t position,
- const uint8_t* ringbuffer, size_t ringbuffer_mask) {
- if (num_bytes >= FN(HashTypeLength)() - 1 && position >= 3) {
- /* Prepare the hashes for three last bytes of the last write.
- These could not be calculated before, since they require knowledge
- of both the previous and the current block. */
- FN(Store)(self, ringbuffer, ringbuffer_mask, position - 3);
- FN(Store)(self, ringbuffer, ringbuffer_mask, position - 2);
- FN(Store)(self, ringbuffer, ringbuffer_mask, position - 1);
- }
-}
-
-/* Find a longest backward match of &data[cur_ix & ring_buffer_mask]
- up to the length of max_length and stores the position cur_ix in the
- hash table.
-
- Does not look for matches longer than max_length.
- Does not look for matches further away than max_backward.
- Writes the best match into |out|.
- Returns true if match is found, otherwise false. */
-static BROTLI_INLINE BROTLI_BOOL FN(FindLongestMatch)(
- HashLongestMatchQuickly* self, const uint8_t* BROTLI_RESTRICT data,
- const size_t ring_buffer_mask, const int* BROTLI_RESTRICT distance_cache,
- const size_t cur_ix, const size_t max_length, const size_t max_backward,
- HasherSearchResult* BROTLI_RESTRICT out) {
- const size_t best_len_in = out->len;
- const size_t cur_ix_masked = cur_ix & ring_buffer_mask;
- const uint32_t key = FN(HashBytes)(&data[cur_ix_masked]);
- int compare_char = data[cur_ix_masked + best_len_in];
- score_t best_score = out->score;
- size_t best_len = best_len_in;
- size_t cached_backward = (size_t)distance_cache[0];
- size_t prev_ix = cur_ix - cached_backward;
- BROTLI_BOOL is_match_found = BROTLI_FALSE;
- out->len_x_code = 0;
- if (prev_ix < cur_ix) {
- prev_ix &= (uint32_t)ring_buffer_mask;
- if (compare_char == data[prev_ix + best_len]) {
- size_t len = FindMatchLengthWithLimit(&data[prev_ix],
- &data[cur_ix_masked],
- max_length);
- if (len >= 4) {
- best_score = BackwardReferenceScoreUsingLastDistance(len, 0);
- best_len = len;
- out->len = len;
- out->distance = cached_backward;
- out->score = best_score;
- compare_char = data[cur_ix_masked + best_len];
- if (BUCKET_SWEEP == 1) {
- self->buckets_[key] = (uint32_t)cur_ix;
- return BROTLI_TRUE;
- } else {
- is_match_found = BROTLI_TRUE;
- }
- }
- }
- }
- if (BUCKET_SWEEP == 1) {
- size_t backward;
- size_t len;
- /* Only one to look for, don't bother to prepare for a loop. */
- prev_ix = self->buckets_[key];
- self->buckets_[key] = (uint32_t)cur_ix;
- backward = cur_ix - prev_ix;
- prev_ix &= (uint32_t)ring_buffer_mask;
- if (compare_char != data[prev_ix + best_len_in]) {
- return BROTLI_FALSE;
- }
- if (PREDICT_FALSE(backward == 0 || backward > max_backward)) {
- return BROTLI_FALSE;
- }
- len = FindMatchLengthWithLimit(&data[prev_ix],
- &data[cur_ix_masked],
- max_length);
- if (len >= 4) {
- out->len = len;
- out->distance = backward;
- out->score = BackwardReferenceScore(len, backward);
- return BROTLI_TRUE;
- }
- } else {
- uint32_t *bucket = self->buckets_ + key;
- int i;
- prev_ix = *bucket++;
- for (i = 0; i < BUCKET_SWEEP; ++i, prev_ix = *bucket++) {
- const size_t backward = cur_ix - prev_ix;
- size_t len;
- prev_ix &= (uint32_t)ring_buffer_mask;
- if (compare_char != data[prev_ix + best_len]) {
- continue;
- }
- if (PREDICT_FALSE(backward == 0 || backward > max_backward)) {
- continue;
- }
- len = FindMatchLengthWithLimit(&data[prev_ix],
- &data[cur_ix_masked],
- max_length);
- if (len >= 4) {
- const score_t score = BackwardReferenceScore(len, backward);
- if (best_score < score) {
- best_score = score;
- best_len = len;
- out->len = best_len;
- out->distance = backward;
- out->score = score;
- compare_char = data[cur_ix_masked + best_len];
- is_match_found = BROTLI_TRUE;
- }
- }
- }
- }
- if (USE_DICTIONARY && !is_match_found) {
- is_match_found = SearchInStaticDictionary(&self->dict_search_stats_,
- &data[cur_ix_masked], max_length, max_backward, out, BROTLI_TRUE);
- }
- self->buckets_[key + ((cur_ix >> 3) % BUCKET_SWEEP)] = (uint32_t)cur_ix;
- return is_match_found;
-}
-
-#undef HASH_MAP_SIZE
-#undef BUCKET_SIZE
-
-#undef HashLongestMatchQuickly
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