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diff --git a/deps/node/deps/brotli/c/enc/cluster_inc.h b/deps/node/deps/brotli/c/enc/cluster_inc.h
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--- a/deps/node/deps/brotli/c/enc/cluster_inc.h
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@@ -1,317 +0,0 @@
-/* NOLINT(build/header_guard) */
-/* Copyright 2013 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, CODE */
-
-#define HistogramType FN(Histogram)
-
-/* Computes the bit cost reduction by combining out[idx1] and out[idx2] and if
- it is below a threshold, stores the pair (idx1, idx2) in the *pairs queue. */
-BROTLI_INTERNAL void FN(BrotliCompareAndPushToQueue)(
- const HistogramType* out, const uint32_t* cluster_size, uint32_t idx1,
- uint32_t idx2, size_t max_num_pairs, HistogramPair* pairs,
- size_t* num_pairs) CODE({
- BROTLI_BOOL is_good_pair = BROTLI_FALSE;
- HistogramPair p;
- p.idx1 = p.idx2 = 0;
- p.cost_diff = p.cost_combo = 0;
- if (idx1 == idx2) {
- return;
- }
- if (idx2 < idx1) {
- uint32_t t = idx2;
- idx2 = idx1;
- idx1 = t;
- }
- p.idx1 = idx1;
- p.idx2 = idx2;
- p.cost_diff = 0.5 * ClusterCostDiff(cluster_size[idx1], cluster_size[idx2]);
- p.cost_diff -= out[idx1].bit_cost_;
- p.cost_diff -= out[idx2].bit_cost_;
-
- if (out[idx1].total_count_ == 0) {
- p.cost_combo = out[idx2].bit_cost_;
- is_good_pair = BROTLI_TRUE;
- } else if (out[idx2].total_count_ == 0) {
- p.cost_combo = out[idx1].bit_cost_;
- is_good_pair = BROTLI_TRUE;
- } else {
- double threshold = *num_pairs == 0 ? 1e99 :
- BROTLI_MAX(double, 0.0, pairs[0].cost_diff);
- HistogramType combo = out[idx1];
- double cost_combo;
- FN(HistogramAddHistogram)(&combo, &out[idx2]);
- cost_combo = FN(BrotliPopulationCost)(&combo);
- if (cost_combo < threshold - p.cost_diff) {
- p.cost_combo = cost_combo;
- is_good_pair = BROTLI_TRUE;
- }
- }
- if (is_good_pair) {
- p.cost_diff += p.cost_combo;
- if (*num_pairs > 0 && HistogramPairIsLess(&pairs[0], &p)) {
- /* Replace the top of the queue if needed. */
- if (*num_pairs < max_num_pairs) {
- pairs[*num_pairs] = pairs[0];
- ++(*num_pairs);
- }
- pairs[0] = p;
- } else if (*num_pairs < max_num_pairs) {
- pairs[*num_pairs] = p;
- ++(*num_pairs);
- }
- }
-})
-
-BROTLI_INTERNAL size_t FN(BrotliHistogramCombine)(HistogramType* out,
- uint32_t* cluster_size,
- uint32_t* symbols,
- uint32_t* clusters,
- HistogramPair* pairs,
- size_t num_clusters,
- size_t symbols_size,
- size_t max_clusters,
- size_t max_num_pairs) CODE({
- double cost_diff_threshold = 0.0;
- size_t min_cluster_size = 1;
- size_t num_pairs = 0;
-
- {
- /* We maintain a vector of histogram pairs, with the property that the pair
- with the maximum bit cost reduction is the first. */
- size_t idx1;
- for (idx1 = 0; idx1 < num_clusters; ++idx1) {
- size_t idx2;
- for (idx2 = idx1 + 1; idx2 < num_clusters; ++idx2) {
- FN(BrotliCompareAndPushToQueue)(out, cluster_size, clusters[idx1],
- clusters[idx2], max_num_pairs, &pairs[0], &num_pairs);
- }
- }
- }
-
- while (num_clusters > min_cluster_size) {
- uint32_t best_idx1;
- uint32_t best_idx2;
- size_t i;
- if (pairs[0].cost_diff >= cost_diff_threshold) {
- cost_diff_threshold = 1e99;
- min_cluster_size = max_clusters;
- continue;
- }
- /* Take the best pair from the top of heap. */
- best_idx1 = pairs[0].idx1;
- best_idx2 = pairs[0].idx2;
- FN(HistogramAddHistogram)(&out[best_idx1], &out[best_idx2]);
- out[best_idx1].bit_cost_ = pairs[0].cost_combo;
- cluster_size[best_idx1] += cluster_size[best_idx2];
- for (i = 0; i < symbols_size; ++i) {
- if (symbols[i] == best_idx2) {
- symbols[i] = best_idx1;
- }
- }
- for (i = 0; i < num_clusters; ++i) {
- if (clusters[i] == best_idx2) {
- memmove(&clusters[i], &clusters[i + 1],
- (num_clusters - i - 1) * sizeof(clusters[0]));
- break;
- }
- }
- --num_clusters;
- {
- /* Remove pairs intersecting the just combined best pair. */
- size_t copy_to_idx = 0;
- for (i = 0; i < num_pairs; ++i) {
- HistogramPair* p = &pairs[i];
- if (p->idx1 == best_idx1 || p->idx2 == best_idx1 ||
- p->idx1 == best_idx2 || p->idx2 == best_idx2) {
- /* Remove invalid pair from the queue. */
- continue;
- }
- if (HistogramPairIsLess(&pairs[0], p)) {
- /* Replace the top of the queue if needed. */
- HistogramPair front = pairs[0];
- pairs[0] = *p;
- pairs[copy_to_idx] = front;
- } else {
- pairs[copy_to_idx] = *p;
- }
- ++copy_to_idx;
- }
- num_pairs = copy_to_idx;
- }
-
- /* Push new pairs formed with the combined histogram to the heap. */
- for (i = 0; i < num_clusters; ++i) {
- FN(BrotliCompareAndPushToQueue)(out, cluster_size, best_idx1, clusters[i],
- max_num_pairs, &pairs[0], &num_pairs);
- }
- }
- return num_clusters;
-})
-
-/* What is the bit cost of moving histogram from cur_symbol to candidate. */
-BROTLI_INTERNAL double FN(BrotliHistogramBitCostDistance)(
- const HistogramType* histogram, const HistogramType* candidate) CODE({
- if (histogram->total_count_ == 0) {
- return 0.0;
- } else {
- HistogramType tmp = *histogram;
- FN(HistogramAddHistogram)(&tmp, candidate);
- return FN(BrotliPopulationCost)(&tmp) - candidate->bit_cost_;
- }
-})
-
-/* Find the best 'out' histogram for each of the 'in' histograms.
- When called, clusters[0..num_clusters) contains the unique values from
- symbols[0..in_size), but this property is not preserved in this function.
- Note: we assume that out[]->bit_cost_ is already up-to-date. */
-BROTLI_INTERNAL void FN(BrotliHistogramRemap)(const HistogramType* in,
- size_t in_size, const uint32_t* clusters, size_t num_clusters,
- HistogramType* out, uint32_t* symbols) CODE({
- size_t i;
- for (i = 0; i < in_size; ++i) {
- uint32_t best_out = i == 0 ? symbols[0] : symbols[i - 1];
- double best_bits =
- FN(BrotliHistogramBitCostDistance)(&in[i], &out[best_out]);
- size_t j;
- for (j = 0; j < num_clusters; ++j) {
- const double cur_bits =
- FN(BrotliHistogramBitCostDistance)(&in[i], &out[clusters[j]]);
- if (cur_bits < best_bits) {
- best_bits = cur_bits;
- best_out = clusters[j];
- }
- }
- symbols[i] = best_out;
- }
-
- /* Recompute each out based on raw and symbols. */
- for (i = 0; i < num_clusters; ++i) {
- FN(HistogramClear)(&out[clusters[i]]);
- }
- for (i = 0; i < in_size; ++i) {
- FN(HistogramAddHistogram)(&out[symbols[i]], &in[i]);
- }
-})
-
-/* Reorders elements of the out[0..length) array and changes values in
- symbols[0..length) array in the following way:
- * when called, symbols[] contains indexes into out[], and has N unique
- values (possibly N < length)
- * on return, symbols'[i] = f(symbols[i]) and
- out'[symbols'[i]] = out[symbols[i]], for each 0 <= i < length,
- where f is a bijection between the range of symbols[] and [0..N), and
- the first occurrences of values in symbols'[i] come in consecutive
- increasing order.
- Returns N, the number of unique values in symbols[]. */
-BROTLI_INTERNAL size_t FN(BrotliHistogramReindex)(MemoryManager* m,
- HistogramType* out, uint32_t* symbols, size_t length) CODE({
- static const uint32_t kInvalidIndex = BROTLI_UINT32_MAX;
- uint32_t* new_index = BROTLI_ALLOC(m, uint32_t, length);
- uint32_t next_index;
- HistogramType* tmp;
- size_t i;
- if (BROTLI_IS_OOM(m)) return 0;
- for (i = 0; i < length; ++i) {
- new_index[i] = kInvalidIndex;
- }
- next_index = 0;
- for (i = 0; i < length; ++i) {
- if (new_index[symbols[i]] == kInvalidIndex) {
- new_index[symbols[i]] = next_index;
- ++next_index;
- }
- }
- /* TODO: by using idea of "cycle-sort" we can avoid allocation of
- tmp and reduce the number of copying by the factor of 2. */
- tmp = BROTLI_ALLOC(m, HistogramType, next_index);
- if (BROTLI_IS_OOM(m)) return 0;
- next_index = 0;
- for (i = 0; i < length; ++i) {
- if (new_index[symbols[i]] == next_index) {
- tmp[next_index] = out[symbols[i]];
- ++next_index;
- }
- symbols[i] = new_index[symbols[i]];
- }
- BROTLI_FREE(m, new_index);
- for (i = 0; i < next_index; ++i) {
- out[i] = tmp[i];
- }
- BROTLI_FREE(m, tmp);
- return next_index;
-})
-
-BROTLI_INTERNAL void FN(BrotliClusterHistograms)(
- MemoryManager* m, const HistogramType* in, const size_t in_size,
- size_t max_histograms, HistogramType* out, size_t* out_size,
- uint32_t* histogram_symbols) CODE({
- uint32_t* cluster_size = BROTLI_ALLOC(m, uint32_t, in_size);
- uint32_t* clusters = BROTLI_ALLOC(m, uint32_t, in_size);
- size_t num_clusters = 0;
- const size_t max_input_histograms = 64;
- size_t pairs_capacity = max_input_histograms * max_input_histograms / 2;
- /* For the first pass of clustering, we allow all pairs. */
- HistogramPair* pairs = BROTLI_ALLOC(m, HistogramPair, pairs_capacity + 1);
- size_t i;
-
- if (BROTLI_IS_OOM(m)) return;
-
- for (i = 0; i < in_size; ++i) {
- cluster_size[i] = 1;
- }
-
- for (i = 0; i < in_size; ++i) {
- out[i] = in[i];
- out[i].bit_cost_ = FN(BrotliPopulationCost)(&in[i]);
- histogram_symbols[i] = (uint32_t)i;
- }
-
- for (i = 0; i < in_size; i += max_input_histograms) {
- size_t num_to_combine =
- BROTLI_MIN(size_t, in_size - i, max_input_histograms);
- size_t num_new_clusters;
- size_t j;
- for (j = 0; j < num_to_combine; ++j) {
- clusters[num_clusters + j] = (uint32_t)(i + j);
- }
- num_new_clusters =
- FN(BrotliHistogramCombine)(out, cluster_size,
- &histogram_symbols[i],
- &clusters[num_clusters], pairs,
- num_to_combine, num_to_combine,
- max_histograms, pairs_capacity);
- num_clusters += num_new_clusters;
- }
-
- {
- /* For the second pass, we limit the total number of histogram pairs.
- After this limit is reached, we only keep searching for the best pair. */
- size_t max_num_pairs = BROTLI_MIN(size_t,
- 64 * num_clusters, (num_clusters / 2) * num_clusters);
- BROTLI_ENSURE_CAPACITY(
- m, HistogramPair, pairs, pairs_capacity, max_num_pairs + 1);
- if (BROTLI_IS_OOM(m)) return;
-
- /* Collapse similar histograms. */
- num_clusters = FN(BrotliHistogramCombine)(out, cluster_size,
- histogram_symbols, clusters,
- pairs, num_clusters, in_size,
- max_histograms, max_num_pairs);
- }
- BROTLI_FREE(m, pairs);
- BROTLI_FREE(m, cluster_size);
- /* Find the optimal map from original histograms to the final ones. */
- FN(BrotliHistogramRemap)(in, in_size, clusters, num_clusters,
- out, histogram_symbols);
- BROTLI_FREE(m, clusters);
- /* Convert the context map to a canonical form. */
- *out_size = FN(BrotliHistogramReindex)(m, out, histogram_symbols, in_size);
- if (BROTLI_IS_OOM(m)) return;
-})
-
-#undef HistogramType
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