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diff --git a/modules/brotli/dec/huffman.h b/modules/brotli/dec/huffman.h
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+++ b/modules/brotli/dec/huffman.h
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+/* Copyright 2013 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+/* Utilities for building Huffman decoding tables. */
+
+#ifndef BROTLI_DEC_HUFFMAN_H_
+#define BROTLI_DEC_HUFFMAN_H_
+
+#include <brotli/types.h>
+
+#include "../common/platform.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+#define BROTLI_HUFFMAN_MAX_CODE_LENGTH 15
+
+/* BROTLI_NUM_BLOCK_LEN_SYMBOLS == 26 */
+#define BROTLI_HUFFMAN_MAX_SIZE_26 396
+/* BROTLI_MAX_BLOCK_TYPE_SYMBOLS == 258 */
+#define BROTLI_HUFFMAN_MAX_SIZE_258 632
+/* BROTLI_MAX_CONTEXT_MAP_SYMBOLS == 272 */
+#define BROTLI_HUFFMAN_MAX_SIZE_272 646
+
+#define BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH 5
+
+#if ((defined(BROTLI_TARGET_ARMV7) || defined(BROTLI_TARGET_ARMV8_32)) && \
+  BROTLI_GNUC_HAS_ATTRIBUTE(aligned, 2, 7, 0))
+#define BROTLI_HUFFMAN_CODE_FAST_LOAD
+#endif
+
+#if !defined(BROTLI_HUFFMAN_CODE_FAST_LOAD)
+/* Do not create this struct directly - use the ConstructHuffmanCode
+ * constructor below! */
+typedef struct {
+  uint8_t bits;    /* number of bits used for this symbol */
+  uint16_t value;  /* symbol value or table offset */
+} HuffmanCode;
+
+static BROTLI_INLINE HuffmanCode ConstructHuffmanCode(const uint8_t bits,
+    const uint16_t value) {
+  HuffmanCode h;
+  h.bits = bits;
+  h.value = value;
+  return h;
+}
+
+/* Please use the following macros to optimize HuffmanCode accesses in hot
+ * paths.
+ *
+ * For example, assuming |table| contains a HuffmanCode pointer:
+ *
+ *   BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table);
+ *   BROTLI_HC_ADJUST_TABLE_INDEX(table, index_into_table);
+ *   *bits = BROTLI_HC_GET_BITS(table);
+ *   *value = BROTLI_HC_GET_VALUE(table);
+ *   BROTLI_HC_ADJUST_TABLE_INDEX(table, offset);
+ *   *bits2 = BROTLI_HC_GET_BITS(table);
+ *   *value2 = BROTLI_HC_GET_VALUE(table);
+ *
+ */
+
+#define BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(H)
+#define BROTLI_HC_ADJUST_TABLE_INDEX(H, V) H += (V)
+
+/* These must be given a HuffmanCode pointer! */
+#define BROTLI_HC_FAST_LOAD_BITS(H) (H->bits)
+#define BROTLI_HC_FAST_LOAD_VALUE(H) (H->value)
+
+#else /* BROTLI_HUFFMAN_CODE_FAST_LOAD */
+
+typedef BROTLI_ALIGNED(4) uint32_t HuffmanCode;
+
+static BROTLI_INLINE HuffmanCode ConstructHuffmanCode(const uint8_t bits,
+    const uint16_t value) {
+  return (HuffmanCode) ((value & 0xFFFF) << 16) | (bits & 0xFF);
+}
+
+#define BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(H) uint32_t __fastload_##H = (*H)
+#define BROTLI_HC_ADJUST_TABLE_INDEX(H, V) H += (V); __fastload_##H = (*H)
+
+/* These must be given a HuffmanCode pointer! */
+#define BROTLI_HC_FAST_LOAD_BITS(H) ((__fastload_##H) & 0xFF)
+#define BROTLI_HC_FAST_LOAD_VALUE(H) ((__fastload_##H) >> 16)
+#endif /* BROTLI_HUFFMAN_CODE_FAST_LOAD */
+
+/* Builds Huffman lookup table assuming code lengths are in symbol order. */
+BROTLI_INTERNAL void BrotliBuildCodeLengthsHuffmanTable(HuffmanCode* root_table,
+    const uint8_t* const code_lengths, uint16_t* count);
+
+/* Builds Huffman lookup table assuming code lengths are in symbol order.
+   Returns size of resulting table. */
+BROTLI_INTERNAL uint32_t BrotliBuildHuffmanTable(HuffmanCode* root_table,
+    int root_bits, const uint16_t* const symbol_lists, uint16_t* count);
+
+/* Builds a simple Huffman table. The |num_symbols| parameter is to be
+   interpreted as follows: 0 means 1 symbol, 1 means 2 symbols,
+   2 means 3 symbols, 3 means 4 symbols with lengths [2, 2, 2, 2],
+   4 means 4 symbols with lengths [1, 2, 3, 3]. */
+BROTLI_INTERNAL uint32_t BrotliBuildSimpleHuffmanTable(HuffmanCode* table,
+    int root_bits, uint16_t* symbols, uint32_t num_symbols);
+
+/* Contains a collection of Huffman trees with the same alphabet size. */
+/* alphabet_size_limit is needed due to simple codes, since
+   log2(alphabet_size_max) could be greater than log2(alphabet_size_limit). */
+typedef struct {
+  HuffmanCode** htrees;
+  HuffmanCode* codes;
+  uint16_t alphabet_size_max;
+  uint16_t alphabet_size_limit;
+  uint16_t num_htrees;
+} HuffmanTreeGroup;
+
+#if defined(__cplusplus) || defined(c_plusplus)
+}  /* extern "C" */
+#endif
+
+#endif  /* BROTLI_DEC_HUFFMAN_H_ */