- Copy Brotli algorithm 3rd party source code for tool Cc: Liming Gao <liming.gao@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Bell Song <binx.song@intel.com> Reviewed-by: Liming Gao <liming.gao@intel.com>
		
			
				
	
	
		
			718 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			718 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright 2010 Google Inc. All Rights Reserved.
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| 
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|    Distributed under MIT license.
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|    See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
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| */
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| 
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| /* A (forgetful) hash table to the data seen by the compressor, to
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|    help create backward references to previous data. */
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| 
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| #ifndef BROTLI_ENC_HASH_H_
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| #define BROTLI_ENC_HASH_H_
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| 
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| #include <string.h>  /* memcmp, memset */
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| 
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| #include "../common/constants.h"
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| #include "../common/dictionary.h"
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| #include "../common/types.h"
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| #include "./dictionary_hash.h"
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| #include "./fast_log.h"
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| #include "./find_match_length.h"
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| #include "./memory.h"
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| #include "./port.h"
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| #include "./quality.h"
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| #include "./static_dict.h"
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| 
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| #if defined(__cplusplus) || defined(c_plusplus)
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| extern "C" {
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| #endif
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| 
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| #define MAX_TREE_SEARCH_DEPTH 64
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| #define MAX_TREE_COMP_LENGTH 128
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| #define score_t size_t
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| 
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| static const uint32_t kDistanceCacheIndex[] = {
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|   0, 1, 2, 3, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1,
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| };
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| static const int kDistanceCacheOffset[] = {
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|   0, 0, 0, 0, -1, 1, -2, 2, -3, 3, -1, 1, -2, 2, -3, 3
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| };
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| 
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| static const uint32_t kCutoffTransformsCount = 10;
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| static const uint8_t kCutoffTransforms[] = {
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|   0, 12, 27, 23, 42, 63, 56, 48, 59, 64
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| };
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| 
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| typedef struct HasherSearchResult {
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|   size_t len;
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|   size_t len_x_code; /* == len ^ len_code */
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|   size_t distance;
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|   score_t score;
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| } HasherSearchResult;
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| 
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| typedef struct DictionarySearchStatictics {
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|   size_t num_lookups;
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|   size_t num_matches;
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| } DictionarySearchStatictics;
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| 
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| /* kHashMul32 multiplier has these properties:
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|    * The multiplier must be odd. Otherwise we may lose the highest bit.
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|    * No long streaks of 1s or 0s.
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|    * There is no effort to ensure that it is a prime, the oddity is enough
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|      for this use.
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|    * The number has been tuned heuristically against compression benchmarks. */
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| static const uint32_t kHashMul32 = 0x1e35a7bd;
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| 
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| static BROTLI_INLINE uint32_t Hash14(const uint8_t* data) {
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|   uint32_t h = BROTLI_UNALIGNED_LOAD32(data) * kHashMul32;
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|   /* The higher bits contain more mixture from the multiplication,
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|      so we take our results from there. */
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|   return h >> (32 - 14);
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| }
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| 
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| #define BROTLI_LITERAL_BYTE_SCORE 540
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| #define BROTLI_DISTANCE_BIT_PENALTY 120
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| /* Score must be positive after applying maximal penalty. */
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| #define BROTLI_SCORE_BASE (BROTLI_DISTANCE_BIT_PENALTY * 8 * sizeof(size_t))
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| 
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| /* Usually, we always choose the longest backward reference. This function
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|    allows for the exception of that rule.
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| 
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|    If we choose a backward reference that is further away, it will
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|    usually be coded with more bits. We approximate this by assuming
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|    log2(distance). If the distance can be expressed in terms of the
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|    last four distances, we use some heuristic constants to estimate
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|    the bits cost. For the first up to four literals we use the bit
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|    cost of the literals from the literal cost model, after that we
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|    use the average bit cost of the cost model.
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| 
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|    This function is used to sometimes discard a longer backward reference
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|    when it is not much longer and the bit cost for encoding it is more
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|    than the saved literals.
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| 
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|    backward_reference_offset MUST be positive. */
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| static BROTLI_INLINE score_t BackwardReferenceScore(
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|     size_t copy_length, size_t backward_reference_offset) {
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|   return BROTLI_SCORE_BASE + BROTLI_LITERAL_BYTE_SCORE * (score_t)copy_length -
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|       BROTLI_DISTANCE_BIT_PENALTY * Log2FloorNonZero(backward_reference_offset);
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| }
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| 
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| static const score_t kDistanceShortCodeCost[BROTLI_NUM_DISTANCE_SHORT_CODES] = {
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|   /* Repeat last */
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|   BROTLI_SCORE_BASE +  60,
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|   /* 2nd, 3rd, 4th last */
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|   BROTLI_SCORE_BASE -  95,
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|   BROTLI_SCORE_BASE - 117,
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|   BROTLI_SCORE_BASE - 127,
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|   /* Last with offset */
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|   BROTLI_SCORE_BASE -  93,
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|   BROTLI_SCORE_BASE -  93,
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|   BROTLI_SCORE_BASE -  96,
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|   BROTLI_SCORE_BASE -  96,
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|   BROTLI_SCORE_BASE -  99,
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|   BROTLI_SCORE_BASE -  99,
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|   /* 2nd last with offset */
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|   BROTLI_SCORE_BASE - 105,
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|   BROTLI_SCORE_BASE - 105,
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|   BROTLI_SCORE_BASE - 115,
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|   BROTLI_SCORE_BASE - 115,
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|   BROTLI_SCORE_BASE - 125,
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|   BROTLI_SCORE_BASE - 125
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| };
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| 
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| static BROTLI_INLINE score_t BackwardReferenceScoreUsingLastDistance(
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|     size_t copy_length, size_t distance_short_code) {
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|   return BROTLI_LITERAL_BYTE_SCORE * (score_t)copy_length +
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|       kDistanceShortCodeCost[distance_short_code];
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| }
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| 
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| static BROTLI_INLINE void DictionarySearchStaticticsReset(
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|     DictionarySearchStatictics* self) {
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|   self->num_lookups = 0;
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|   self->num_matches = 0;
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| }
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| 
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| static BROTLI_INLINE BROTLI_BOOL TestStaticDictionaryItem(
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|     size_t item, const uint8_t* data, size_t max_length, size_t max_backward,
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|     HasherSearchResult* out) {
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|   size_t len;
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|   size_t dist;
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|   size_t offset;
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|   size_t matchlen;
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|   size_t backward;
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|   score_t score;
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|   len = item & 31;
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|   dist = item >> 5;
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|   offset = kBrotliDictionaryOffsetsByLength[len] + len * dist;
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|   if (len > max_length) {
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|     return BROTLI_FALSE;
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|   }
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| 
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|   matchlen = FindMatchLengthWithLimit(data, &kBrotliDictionary[offset], len);
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|   if (matchlen + kCutoffTransformsCount <= len || matchlen == 0) {
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|     return BROTLI_FALSE;
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|   }
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|   {
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|     size_t transform_id = kCutoffTransforms[len - matchlen];
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|     backward = max_backward + dist + 1 +
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|         (transform_id << kBrotliDictionarySizeBitsByLength[len]);
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|   }
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|   score = BackwardReferenceScore(matchlen, backward);
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|   if (score < out->score) {
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|     return BROTLI_FALSE;
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|   }
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|   out->len = matchlen;
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|   out->len_x_code = len ^ matchlen;
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|   out->distance = backward;
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|   out->score = score;
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|   return BROTLI_TRUE;
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| }
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| 
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| static BROTLI_INLINE BROTLI_BOOL SearchInStaticDictionary(
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|     DictionarySearchStatictics* self, const uint8_t* data, size_t max_length,
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|     size_t max_backward, HasherSearchResult* out, BROTLI_BOOL shallow) {
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|   size_t key;
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|   size_t i;
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|   BROTLI_BOOL is_match_found = BROTLI_FALSE;
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|   if (self->num_matches < (self->num_lookups >> 7)) {
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|     return BROTLI_FALSE;
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|   }
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|   key = Hash14(data) << 1;
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|   for (i = 0; i < (shallow ? 1 : 2); ++i, ++key) {
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|     size_t item = kStaticDictionaryHash[key];
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|     self->num_lookups++;
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|     if (item != 0 &&
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|         TestStaticDictionaryItem(item, data, max_length, max_backward, out)) {
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|       self->num_matches++;
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|       is_match_found = BROTLI_TRUE;
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|     }
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|   }
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|   return is_match_found;
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| }
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| 
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| typedef struct BackwardMatch {
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|   uint32_t distance;
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|   uint32_t length_and_code;
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| } BackwardMatch;
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| 
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| static BROTLI_INLINE void InitBackwardMatch(BackwardMatch* self,
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|     size_t dist, size_t len) {
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|   self->distance = (uint32_t)dist;
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|   self->length_and_code = (uint32_t)(len << 5);
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| }
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| 
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| static BROTLI_INLINE void InitDictionaryBackwardMatch(BackwardMatch* self,
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|     size_t dist, size_t len, size_t len_code) {
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|   self->distance = (uint32_t)dist;
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|   self->length_and_code =
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|       (uint32_t)((len << 5) | (len == len_code ? 0 : len_code));
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| }
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| 
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| static BROTLI_INLINE size_t BackwardMatchLength(const BackwardMatch* self) {
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|   return self->length_and_code >> 5;
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| }
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| 
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| static BROTLI_INLINE size_t BackwardMatchLengthCode(const BackwardMatch* self) {
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|   size_t code = self->length_and_code & 31;
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|   return code ? code : BackwardMatchLength(self);
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| }
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| 
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| #define EXPAND_CAT(a, b) CAT(a, b)
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| #define CAT(a, b) a ## b
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| #define FN(X) EXPAND_CAT(X, HASHER())
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| 
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| #define MAX_NUM_MATCHES_H10 (64 + MAX_TREE_SEARCH_DEPTH)
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| 
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| #define HASHER() H10
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| #define HashToBinaryTree HASHER()
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| 
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| #define BUCKET_BITS 17
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| #define BUCKET_SIZE (1 << BUCKET_BITS)
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| 
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| static size_t FN(HashTypeLength)(void) { return 4; }
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| static size_t FN(StoreLookahead)(void) { return MAX_TREE_COMP_LENGTH; }
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| 
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| static uint32_t FN(HashBytes)(const uint8_t *data) {
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|   uint32_t h = BROTLI_UNALIGNED_LOAD32(data) * kHashMul32;
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|   /* The higher bits contain more mixture from the multiplication,
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|      so we take our results from there. */
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|   return h >> (32 - BUCKET_BITS);
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| }
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| 
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| /* A (forgetful) hash table where each hash bucket contains a binary tree of
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|    sequences whose first 4 bytes share the same hash code.
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|    Each sequence is MAX_TREE_COMP_LENGTH long and is identified by its starting
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|    position in the input data. The binary tree is sorted by the lexicographic
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|    order of the sequences, and it is also a max-heap with respect to the
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|    starting positions. */
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| typedef struct HashToBinaryTree {
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|   /* The window size minus 1 */
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|   size_t window_mask_;
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| 
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|   /* Hash table that maps the 4-byte hashes of the sequence to the last
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|      position where this hash was found, which is the root of the binary
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|      tree of sequences that share this hash bucket. */
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|   uint32_t buckets_[BUCKET_SIZE];
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| 
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|   /* The union of the binary trees of each hash bucket. The root of the tree
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|      corresponding to a hash is a sequence starting at buckets_[hash] and
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|      the left and right children of a sequence starting at pos are
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|      forest_[2 * pos] and forest_[2 * pos + 1]. */
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|   uint32_t* forest_;
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| 
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|   /* A position used to mark a non-existent sequence, i.e. a tree is empty if
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|      its root is at invalid_pos_ and a node is a leaf if both its children
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|      are at invalid_pos_. */
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|   uint32_t invalid_pos_;
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| 
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|   size_t forest_size_;
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|   BROTLI_BOOL is_dirty_;
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| } HashToBinaryTree;
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| 
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| static void FN(Reset)(HashToBinaryTree* self) {
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|   self->is_dirty_ = BROTLI_TRUE;
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| }
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| 
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| static void FN(Initialize)(HashToBinaryTree* self) {
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|   self->forest_ = NULL;
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|   self->forest_size_ = 0;
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|   FN(Reset)(self);
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| }
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| 
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| static void FN(Cleanup)(MemoryManager* m, HashToBinaryTree* self) {
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|   BROTLI_FREE(m, self->forest_);
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| }
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| 
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| static void FN(Init)(
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|     MemoryManager* m, HashToBinaryTree* self, const uint8_t* data,
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|     const BrotliEncoderParams* params, size_t position, size_t bytes,
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|     BROTLI_BOOL is_last) {
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|   if (self->is_dirty_) {
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|     uint32_t invalid_pos;
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|     size_t num_nodes;
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|     uint32_t i;
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|     BROTLI_UNUSED(data);
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|     self->window_mask_ = (1u << params->lgwin) - 1u;
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|     invalid_pos = (uint32_t)(0 - self->window_mask_);
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|     self->invalid_pos_ = invalid_pos;
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|     for (i = 0; i < BUCKET_SIZE; i++) {
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|       self->buckets_[i] = invalid_pos;
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|     }
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|     num_nodes = (position == 0 && is_last) ? bytes : self->window_mask_ + 1;
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|     if (num_nodes > self->forest_size_) {
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|       BROTLI_FREE(m, self->forest_);
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|       self->forest_ = BROTLI_ALLOC(m, uint32_t, 2 * num_nodes);
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|       if (BROTLI_IS_OOM(m)) return;
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|       self->forest_size_ = num_nodes;
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|     }
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|     self->is_dirty_ = BROTLI_FALSE;
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|   }
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| }
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| 
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| static BROTLI_INLINE size_t FN(LeftChildIndex)(HashToBinaryTree* self,
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|     const size_t pos) {
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|   return 2 * (pos & self->window_mask_);
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| }
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| 
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| static BROTLI_INLINE size_t FN(RightChildIndex)(HashToBinaryTree* self,
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|     const size_t pos) {
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|   return 2 * (pos & self->window_mask_) + 1;
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| }
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| 
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| /* Stores the hash of the next 4 bytes and in a single tree-traversal, the
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|    hash bucket's binary tree is searched for matches and is re-rooted at the
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|    current position.
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| 
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|    If less than MAX_TREE_COMP_LENGTH data is available, the hash bucket of the
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|    current position is searched for matches, but the state of the hash table
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|    is not changed, since we can not know the final sorting order of the
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|    current (incomplete) sequence.
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| 
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|    This function must be called with increasing cur_ix positions. */
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| static BROTLI_INLINE BackwardMatch* FN(StoreAndFindMatches)(
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|     HashToBinaryTree* self, const uint8_t* const BROTLI_RESTRICT data,
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|     const size_t cur_ix, const size_t ring_buffer_mask, const size_t max_length,
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|     const size_t max_backward, size_t* const BROTLI_RESTRICT best_len,
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|     BackwardMatch* BROTLI_RESTRICT matches) {
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|   const size_t cur_ix_masked = cur_ix & ring_buffer_mask;
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|   const size_t max_comp_len =
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|       BROTLI_MIN(size_t, max_length, MAX_TREE_COMP_LENGTH);
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|   const BROTLI_BOOL should_reroot_tree =
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|       TO_BROTLI_BOOL(max_length >= MAX_TREE_COMP_LENGTH);
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|   const uint32_t key = FN(HashBytes)(&data[cur_ix_masked]);
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|   size_t prev_ix = self->buckets_[key];
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|   /* The forest index of the rightmost node of the left subtree of the new
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|      root, updated as we traverse and reroot the tree of the hash bucket. */
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|   size_t node_left = FN(LeftChildIndex)(self, cur_ix);
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|   /* The forest index of the leftmost node of the right subtree of the new
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|      root, updated as we traverse and reroot the tree of the hash bucket. */
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|   size_t node_right = FN(RightChildIndex)(self, cur_ix);
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|   /* The match length of the rightmost node of the left subtree of the new
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|      root, updated as we traverse and reroot the tree of the hash bucket. */
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|   size_t best_len_left = 0;
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|   /* The match length of the leftmost node of the right subtree of the new
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|      root, updated as we traverse and reroot the tree of the hash bucket. */
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|   size_t best_len_right = 0;
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|   size_t depth_remaining;
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|   if (should_reroot_tree) {
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|     self->buckets_[key] = (uint32_t)cur_ix;
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|   }
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|   for (depth_remaining = MAX_TREE_SEARCH_DEPTH; ; --depth_remaining) {
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|     const size_t backward = cur_ix - prev_ix;
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|     const size_t prev_ix_masked = prev_ix & ring_buffer_mask;
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|     if (backward == 0 || backward > max_backward || depth_remaining == 0) {
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|       if (should_reroot_tree) {
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|         self->forest_[node_left] = self->invalid_pos_;
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|         self->forest_[node_right] = self->invalid_pos_;
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|       }
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|       break;
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|     }
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|     {
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|       const size_t cur_len = BROTLI_MIN(size_t, best_len_left, best_len_right);
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|       size_t len;
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|       assert(cur_len <= MAX_TREE_COMP_LENGTH);
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|       len = cur_len +
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|           FindMatchLengthWithLimit(&data[cur_ix_masked + cur_len],
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|                                    &data[prev_ix_masked + cur_len],
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|                                    max_length - cur_len);
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|       assert(0 == memcmp(&data[cur_ix_masked], &data[prev_ix_masked], len));
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|       if (matches && len > *best_len) {
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|         *best_len = len;
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|         InitBackwardMatch(matches++, backward, len);
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|       }
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|       if (len >= max_comp_len) {
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|         if (should_reroot_tree) {
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|           self->forest_[node_left] =
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|               self->forest_[FN(LeftChildIndex)(self, prev_ix)];
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|           self->forest_[node_right] =
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|               self->forest_[FN(RightChildIndex)(self, prev_ix)];
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|         }
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|         break;
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|       }
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|       if (data[cur_ix_masked + len] > data[prev_ix_masked + len]) {
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|         best_len_left = len;
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|         if (should_reroot_tree) {
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|           self->forest_[node_left] = (uint32_t)prev_ix;
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|         }
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|         node_left = FN(RightChildIndex)(self, prev_ix);
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|         prev_ix = self->forest_[node_left];
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|       } else {
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|         best_len_right = len;
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|         if (should_reroot_tree) {
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|           self->forest_[node_right] = (uint32_t)prev_ix;
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|         }
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|         node_right = FN(LeftChildIndex)(self, prev_ix);
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|         prev_ix = self->forest_[node_right];
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|       }
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|     }
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|   }
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|   return matches;
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| }
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| 
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| /* Finds all backward matches of &data[cur_ix & ring_buffer_mask] up to the
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|    length of max_length and stores the position cur_ix in the hash table.
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| 
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|    Sets *num_matches to the number of matches found, and stores the found
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|    matches in matches[0] to matches[*num_matches - 1]. The matches will be
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|    sorted by strictly increasing length and (non-strictly) increasing
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|    distance. */
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| static BROTLI_INLINE size_t FN(FindAllMatches)(HashToBinaryTree* self,
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|     const uint8_t* data, const size_t ring_buffer_mask, const size_t cur_ix,
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|     const size_t max_length, const size_t max_backward,
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|     const BrotliEncoderParams* params, BackwardMatch* matches) {
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|   BackwardMatch* const orig_matches = matches;
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|   const size_t cur_ix_masked = cur_ix & ring_buffer_mask;
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|   size_t best_len = 1;
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|   const size_t short_match_max_backward =
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|       params->quality != HQ_ZOPFLIFICATION_QUALITY ? 16 : 64;
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|   size_t stop = cur_ix - short_match_max_backward;
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|   uint32_t dict_matches[BROTLI_MAX_STATIC_DICTIONARY_MATCH_LEN + 1];
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|   size_t i;
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|   if (cur_ix < short_match_max_backward) { stop = 0; }
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|   for (i = cur_ix - 1; i > stop && best_len <= 2; --i) {
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|     size_t prev_ix = i;
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|     const size_t backward = cur_ix - prev_ix;
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|     if (PREDICT_FALSE(backward > max_backward)) {
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|       break;
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|     }
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|     prev_ix &= ring_buffer_mask;
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|     if (data[cur_ix_masked] != data[prev_ix] ||
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|         data[cur_ix_masked + 1] != data[prev_ix + 1]) {
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|       continue;
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|     }
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|     {
 | |
|       const size_t len =
 | |
|           FindMatchLengthWithLimit(&data[prev_ix], &data[cur_ix_masked],
 | |
|                                    max_length);
 | |
|       if (len > best_len) {
 | |
|         best_len = len;
 | |
|         InitBackwardMatch(matches++, backward, len);
 | |
|       }
 | |
|     }
 | |
|   }
 | |
|   if (best_len < max_length) {
 | |
|     matches = FN(StoreAndFindMatches)(self, data, cur_ix, ring_buffer_mask,
 | |
|         max_length, max_backward, &best_len, matches);
 | |
|   }
 | |
|   for (i = 0; i <= BROTLI_MAX_STATIC_DICTIONARY_MATCH_LEN; ++i) {
 | |
|     dict_matches[i] = kInvalidMatch;
 | |
|   }
 | |
|   {
 | |
|     size_t minlen = BROTLI_MAX(size_t, 4, best_len + 1);
 | |
|     if (BrotliFindAllStaticDictionaryMatches(&data[cur_ix_masked], minlen,
 | |
|                                              max_length, &dict_matches[0])) {
 | |
|       size_t maxlen = BROTLI_MIN(
 | |
|           size_t, BROTLI_MAX_STATIC_DICTIONARY_MATCH_LEN, max_length);
 | |
|       size_t l;
 | |
|       for (l = minlen; l <= maxlen; ++l) {
 | |
|         uint32_t dict_id = dict_matches[l];
 | |
|         if (dict_id < kInvalidMatch) {
 | |
|           InitDictionaryBackwardMatch(matches++,
 | |
|               max_backward + (dict_id >> 5) + 1, l, dict_id & 31);
 | |
|         }
 | |
|       }
 | |
|     }
 | |
|   }
 | |
|   return (size_t)(matches - orig_matches);
 | |
| }
 | |
| 
 | |
| /* Stores the hash of the next 4 bytes and re-roots the binary tree at the
 | |
|    current sequence, without returning any matches.
 | |
|    REQUIRES: ix + MAX_TREE_COMP_LENGTH <= end-of-current-block */
 | |
| static BROTLI_INLINE void FN(Store)(HashToBinaryTree* self, const uint8_t *data,
 | |
|     const size_t mask, const size_t ix) {
 | |
|   /* Maximum distance is window size - 16, see section 9.1. of the spec. */
 | |
|   const size_t max_backward = self->window_mask_ - 15;
 | |
|   FN(StoreAndFindMatches)(self, data, ix, mask, MAX_TREE_COMP_LENGTH,
 | |
|       max_backward, NULL, NULL);
 | |
| }
 | |
| 
 | |
| static BROTLI_INLINE void FN(StoreRange)(HashToBinaryTree* self,
 | |
|     const uint8_t *data, const size_t mask, const size_t ix_start,
 | |
|     const size_t ix_end) {
 | |
|   size_t i = ix_start + 63 <= ix_end ? ix_end - 63 : ix_start;
 | |
|   for (; i < ix_end; ++i) {
 | |
|     FN(Store)(self, data, mask, i);
 | |
|   }
 | |
| }
 | |
| 
 | |
| static BROTLI_INLINE void FN(StitchToPreviousBlock)(HashToBinaryTree* self,
 | |
|     size_t num_bytes, size_t position, const uint8_t* ringbuffer,
 | |
|     size_t ringbuffer_mask) {
 | |
|   if (num_bytes >= FN(HashTypeLength)() - 1 &&
 | |
|       position >= MAX_TREE_COMP_LENGTH) {
 | |
|     /* Store the last `MAX_TREE_COMP_LENGTH - 1` positions in the hasher.
 | |
|        These could not be calculated before, since they require knowledge
 | |
|        of both the previous and the current block. */
 | |
|     const size_t i_start = position - MAX_TREE_COMP_LENGTH + 1;
 | |
|     const size_t i_end = BROTLI_MIN(size_t, position, i_start + num_bytes);
 | |
|     size_t i;
 | |
|     for (i = i_start; i < i_end; ++i) {
 | |
|       /* Maximum distance is window size - 16, see section 9.1. of the spec.
 | |
|          Furthermore, we have to make sure that we don't look further back
 | |
|          from the start of the next block than the window size, otherwise we
 | |
|          could access already overwritten areas of the ringbuffer. */
 | |
|       const size_t max_backward =
 | |
|           self->window_mask_ - BROTLI_MAX(size_t, 15, position - i);
 | |
|       /* We know that i + MAX_TREE_COMP_LENGTH <= position + num_bytes, i.e. the
 | |
|          end of the current block and that we have at least
 | |
|          MAX_TREE_COMP_LENGTH tail in the ringbuffer. */
 | |
|       FN(StoreAndFindMatches)(self, ringbuffer, i, ringbuffer_mask,
 | |
|           MAX_TREE_COMP_LENGTH, max_backward, NULL, NULL);
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| #undef BUCKET_SIZE
 | |
| #undef BUCKET_BITS
 | |
| 
 | |
| #undef HASHER
 | |
| 
 | |
| /* For BUCKET_SWEEP == 1, enabling the dictionary lookup makes compression
 | |
|    a little faster (0.5% - 1%) and it compresses 0.15% better on small text
 | |
|    and html inputs. */
 | |
| 
 | |
| #define HASHER() H2
 | |
| #define BUCKET_BITS 16
 | |
| #define BUCKET_SWEEP 1
 | |
| #define USE_DICTIONARY 1
 | |
| #include "./hash_longest_match_quickly_inc.h"  /* NOLINT(build/include) */
 | |
| #undef BUCKET_SWEEP
 | |
| #undef USE_DICTIONARY
 | |
| #undef HASHER
 | |
| 
 | |
| #define HASHER() H3
 | |
| #define BUCKET_SWEEP 2
 | |
| #define USE_DICTIONARY 0
 | |
| #include "./hash_longest_match_quickly_inc.h"  /* NOLINT(build/include) */
 | |
| #undef USE_DICTIONARY
 | |
| #undef BUCKET_SWEEP
 | |
| #undef BUCKET_BITS
 | |
| #undef HASHER
 | |
| 
 | |
| #define HASHER() H4
 | |
| #define BUCKET_BITS 17
 | |
| #define BUCKET_SWEEP 4
 | |
| #define USE_DICTIONARY 1
 | |
| #include "./hash_longest_match_quickly_inc.h"  /* NOLINT(build/include) */
 | |
| #undef USE_DICTIONARY
 | |
| #undef BUCKET_SWEEP
 | |
| #undef BUCKET_BITS
 | |
| #undef HASHER
 | |
| 
 | |
| #define HASHER() H5
 | |
| #define BUCKET_BITS 14
 | |
| #define BLOCK_BITS 4
 | |
| #define NUM_LAST_DISTANCES_TO_CHECK 4
 | |
| #include "./hash_longest_match_inc.h"  /* NOLINT(build/include) */
 | |
| #undef BLOCK_BITS
 | |
| #undef HASHER
 | |
| 
 | |
| #define HASHER() H6
 | |
| #define BLOCK_BITS 5
 | |
| #include "./hash_longest_match_inc.h"  /* NOLINT(build/include) */
 | |
| #undef NUM_LAST_DISTANCES_TO_CHECK
 | |
| #undef BLOCK_BITS
 | |
| #undef BUCKET_BITS
 | |
| #undef HASHER
 | |
| 
 | |
| #define HASHER() H7
 | |
| #define BUCKET_BITS 15
 | |
| #define BLOCK_BITS 6
 | |
| #define NUM_LAST_DISTANCES_TO_CHECK 10
 | |
| #include "./hash_longest_match_inc.h"  /* NOLINT(build/include) */
 | |
| #undef BLOCK_BITS
 | |
| #undef HASHER
 | |
| 
 | |
| #define HASHER() H8
 | |
| #define BLOCK_BITS 7
 | |
| #include "./hash_longest_match_inc.h"  /* NOLINT(build/include) */
 | |
| #undef NUM_LAST_DISTANCES_TO_CHECK
 | |
| #undef BLOCK_BITS
 | |
| #undef HASHER
 | |
| 
 | |
| #define HASHER() H9
 | |
| #define BLOCK_BITS 8
 | |
| #define NUM_LAST_DISTANCES_TO_CHECK 16
 | |
| #include "./hash_longest_match_inc.h"  /* NOLINT(build/include) */
 | |
| #undef NUM_LAST_DISTANCES_TO_CHECK
 | |
| #undef BLOCK_BITS
 | |
| #undef BUCKET_BITS
 | |
| #undef HASHER
 | |
| 
 | |
| #define BUCKET_BITS 15
 | |
| 
 | |
| #define NUM_LAST_DISTANCES_TO_CHECK 4
 | |
| #define NUM_BANKS 1
 | |
| #define BANK_BITS 16
 | |
| #define HASHER() H40
 | |
| #include "./hash_forgetful_chain_inc.h"  /* NOLINT(build/include) */
 | |
| #undef HASHER
 | |
| #undef NUM_LAST_DISTANCES_TO_CHECK
 | |
| 
 | |
| #define NUM_LAST_DISTANCES_TO_CHECK 10
 | |
| #define HASHER() H41
 | |
| #include "./hash_forgetful_chain_inc.h"  /* NOLINT(build/include) */
 | |
| #undef HASHER
 | |
| #undef NUM_LAST_DISTANCES_TO_CHECK
 | |
| #undef NUM_BANKS
 | |
| #undef BANK_BITS
 | |
| 
 | |
| #define NUM_LAST_DISTANCES_TO_CHECK 16
 | |
| #define NUM_BANKS 512
 | |
| #define BANK_BITS 9
 | |
| #define HASHER() H42
 | |
| #include "./hash_forgetful_chain_inc.h"  /* NOLINT(build/include) */
 | |
| #undef HASHER
 | |
| #undef NUM_LAST_DISTANCES_TO_CHECK
 | |
| #undef NUM_BANKS
 | |
| #undef BANK_BITS
 | |
| 
 | |
| #undef BUCKET_BITS
 | |
| 
 | |
| #undef FN
 | |
| #undef CAT
 | |
| #undef EXPAND_CAT
 | |
| 
 | |
| #define FOR_GENERIC_HASHERS(H) H(2) H(3) H(4) H(5) H(6) H(7) H(8) H(9) \
 | |
|                                H(40) H(41) H(42)
 | |
| #define FOR_ALL_HASHERS(H) FOR_GENERIC_HASHERS(H) H(10)
 | |
| 
 | |
| typedef struct Hashers {
 | |
| #define _MEMBER(N) H ## N* h ## N;
 | |
|   FOR_ALL_HASHERS(_MEMBER)
 | |
| #undef _MEMBER
 | |
| } Hashers;
 | |
| 
 | |
| static BROTLI_INLINE void InitHashers(Hashers* self) {
 | |
| #define _INIT(N) self->h ## N = 0;
 | |
|   FOR_ALL_HASHERS(_INIT)
 | |
| #undef _INIT
 | |
| }
 | |
| 
 | |
| static BROTLI_INLINE void DestroyHashers(MemoryManager* m, Hashers* self) {
 | |
|   if (self->h10) CleanupH10(m, self->h10);
 | |
| #define _CLEANUP(N) BROTLI_FREE(m, self->h ## N)
 | |
|   FOR_ALL_HASHERS(_CLEANUP)
 | |
| #undef _CLEANUP
 | |
| }
 | |
| 
 | |
| static BROTLI_INLINE void HashersReset(Hashers* self, int type) {
 | |
|   switch (type) {
 | |
| #define _RESET(N) case N: ResetH ## N(self->h ## N); break;
 | |
|     FOR_ALL_HASHERS(_RESET)
 | |
| #undef _RESET
 | |
|     default: break;
 | |
|   }
 | |
| }
 | |
| 
 | |
| static BROTLI_INLINE void HashersSetup(
 | |
|     MemoryManager* m, Hashers* self, int type) {
 | |
|   switch (type) {
 | |
| #define _SETUP(N) case N: self->h ## N = BROTLI_ALLOC(m, H ## N, 1); break;
 | |
|     FOR_ALL_HASHERS(_SETUP)
 | |
| #undef _SETUP
 | |
|     default: break;
 | |
|   }
 | |
|   if (BROTLI_IS_OOM(m)) return;
 | |
|   if (type == 10) InitializeH10(self->h10);
 | |
|   HashersReset(self, type);
 | |
| }
 | |
| 
 | |
| #define _WARMUP_HASH(N)                                                        \
 | |
| static BROTLI_INLINE void WarmupHashH ## N(MemoryManager* m,                   \
 | |
|     const BrotliEncoderParams* params, const size_t size, const uint8_t* dict, \
 | |
|     H ## N* hasher) {                                                          \
 | |
|   size_t overlap = (StoreLookaheadH ## N()) - 1;                               \
 | |
|   size_t i;                                                                    \
 | |
|   InitH ## N(m, hasher, dict, params, 0, size, BROTLI_FALSE);                  \
 | |
|   if (BROTLI_IS_OOM(m)) return;                                                \
 | |
|   for (i = 0; i + overlap < size; i++) {                                       \
 | |
|     StoreH ## N(hasher, dict, ~(size_t)0, i);                                  \
 | |
|   }                                                                            \
 | |
| }
 | |
| FOR_ALL_HASHERS(_WARMUP_HASH)
 | |
| #undef _WARMUP_HASH
 | |
| 
 | |
| /* Custom LZ77 window. */
 | |
| static BROTLI_INLINE void HashersPrependCustomDictionary(
 | |
|     MemoryManager* m, Hashers* self, const BrotliEncoderParams* params,
 | |
|     const size_t size, const uint8_t* dict) {
 | |
|   int hasher_type = ChooseHasher(params);
 | |
|   switch (hasher_type) {
 | |
| #define _PREPEND(N) \
 | |
|     case N: WarmupHashH ## N(m, params, size, dict, self->h ## N); break;
 | |
|     FOR_ALL_HASHERS(_PREPEND)
 | |
| #undef _PREPEND
 | |
|     default: break;
 | |
|   }
 | |
|   if (BROTLI_IS_OOM(m)) return;
 | |
| }
 | |
| 
 | |
| 
 | |
| #if defined(__cplusplus) || defined(c_plusplus)
 | |
| }  /* extern "C" */
 | |
| #endif
 | |
| 
 | |
| #endif  /* BROTLI_ENC_HASH_H_ */
 |