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Added Brotli compress/decompress utilities and makefiles

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This commit is contained in:
Roderick Sheeter
2013-11-19 14:32:56 -08:00
parent 1571db36a9
commit 437bbad370
29 changed files with 3267 additions and 135 deletions
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brotli/enc/hash.h
+42 -34
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@@ -147,6 +147,7 @@ class HashLongestMatch {
uint32_t max_length,
const uint32_t max_backward,
size_t * __restrict best_len_out,
size_t * __restrict best_len_code_out,
size_t * __restrict best_distance_out,
double * __restrict best_score_out) {
const size_t cur_ix_masked = cur_ix & ring_buffer_mask;
@@ -227,6 +228,7 @@ class HashLongestMatch {
best_len = len;
best_ix = backward;
*best_len_out = best_len;
*best_len_code_out = best_len;
*best_distance_out = best_ix;
*best_score_out = best_score;
match_found = true;
@@ -234,7 +236,7 @@ class HashLongestMatch {
}
}
const uint32_t key = Hash3Bytes(&data[cur_ix_masked], kBucketBits);
const uint32_t * __restrict const bucket = &buckets_[key][0];
const int * __restrict const bucket = &buckets_[key][0];
const int down = (num_[key] > kBlockSize) ? (num_[key] - kBlockSize) : 0;
int stop = int(cur_ix) - 64;
if (stop < 0) { stop = 0; }
@@ -259,44 +261,50 @@ class HashLongestMatch {
best_len = len;
best_ix = backward;
*best_len_out = best_len;
*best_len_code_out = best_len;
*best_distance_out = best_ix;
match_found = true;
}
}
for (int i = num_[key] - 1; i >= down; --i) {
size_t prev_ix = bucket[i & kBlockMask];
const size_t backward = cur_ix - prev_ix;
if (PREDICT_FALSE(backward > max_backward)) {
break;
}
prev_ix &= ring_buffer_mask;
if (data[cur_ix_masked + best_len] != data[prev_ix + best_len]) {
int prev_ix = bucket[i & kBlockMask];
if (prev_ix < 0) {
continue;
}
const size_t len =
FindMatchLengthWithLimit(&data[prev_ix], &data[cur_ix_masked],
max_length);
if (len >= 3) {
// Comparing for >= 3 does not change the semantics, but just saves for
// a few unnecessary binary logarithms in backward reference score,
// since we are not interested in such short matches.
const double score = BackwardReferenceScore(average_cost_,
start_cost4,
start_cost3,
start_cost2,
len, backward,
last_distance1_,
last_distance2_,
last_distance3_,
last_distance4_);
if (best_score < score) {
best_score = score;
best_len = len;
best_ix = backward;
*best_len_out = best_len;
*best_distance_out = best_ix;
*best_score_out = best_score;
match_found = true;
} else {
const size_t backward = cur_ix - prev_ix;
if (PREDICT_FALSE(backward > max_backward)) {
break;
}
prev_ix &= ring_buffer_mask;
if (data[cur_ix_masked + best_len] != data[prev_ix + best_len]) {
continue;
}
const size_t len =
FindMatchLengthWithLimit(&data[prev_ix], &data[cur_ix_masked],
max_length);
if (len >= 3) {
// Comparing for >= 3 does not change the semantics, but just saves
// for a few unnecessary binary logarithms in backward reference
// score, since we are not interested in such short matches.
const double score = BackwardReferenceScore(average_cost_,
start_cost4,
start_cost3,
start_cost2,
len, backward,
last_distance1_,
last_distance2_,
last_distance3_,
last_distance4_);
if (best_score < score) {
best_score = score;
best_len = len;
best_ix = backward;
*best_len_out = best_len;
*best_len_code_out = best_len;
*best_distance_out = best_ix;
*best_score_out = best_score;
match_found = true;
}
}
}
}
@@ -333,7 +341,7 @@ class HashLongestMatch {
uint16_t num_[kBucketSize];
// Buckets containing kBlockSize of backward references.
uint32_t buckets_[kBucketSize][kBlockSize];
int buckets_[kBucketSize][kBlockSize];
int last_distance1_;
int last_distance2_;