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diff --git a/web/server/h2o/libh2o/deps/brotli/enc/find_match_length.h b/web/server/h2o/libh2o/deps/brotli/enc/find_match_length.h
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+/* Copyright 2010 Google Inc. All Rights Reserved.
+
+ Distributed under MIT license.
+ See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+// Function to find maximal matching prefixes of strings.
+
+#ifndef BROTLI_ENC_FIND_MATCH_LENGTH_H_
+#define BROTLI_ENC_FIND_MATCH_LENGTH_H_
+
+
+#include "./port.h"
+#include "./types.h"
+
+namespace brotli {
+
+// Separate implementation for little-endian 64-bit targets, for speed.
+#if defined(__GNUC__) && defined(_LP64) && defined(IS_LITTLE_ENDIAN)
+
+static inline size_t FindMatchLengthWithLimit(const uint8_t* s1,
+ const uint8_t* s2,
+ size_t limit) {
+ size_t matched = 0;
+ size_t limit2 = (limit >> 3) + 1; // + 1 is for pre-decrement in while
+ while (PREDICT_TRUE(--limit2)) {
+ if (PREDICT_FALSE(BROTLI_UNALIGNED_LOAD64(s2) ==
+ BROTLI_UNALIGNED_LOAD64(s1 + matched))) {
+ s2 += 8;
+ matched += 8;
+ } else {
+ uint64_t x =
+ BROTLI_UNALIGNED_LOAD64(s2) ^ BROTLI_UNALIGNED_LOAD64(s1 + matched);
+ size_t matching_bits = static_cast<size_t>(__builtin_ctzll(x));
+ matched += matching_bits >> 3;
+ return matched;
+ }
+ }
+ limit = (limit & 7) + 1; // + 1 is for pre-decrement in while
+ while (--limit) {
+ if (PREDICT_TRUE(s1[matched] == *s2)) {
+ ++s2;
+ ++matched;
+ } else {
+ return matched;
+ }
+ }
+ return matched;
+}
+#else
+static inline size_t FindMatchLengthWithLimit(const uint8_t* s1,
+ const uint8_t* s2,
+ size_t limit) {
+ size_t matched = 0;
+ const uint8_t* s2_limit = s2 + limit;
+ const uint8_t* s2_ptr = s2;
+ // Find out how long the match is. We loop over the data 32 bits at a
+ // time until we find a 32-bit block that doesn't match; then we find
+ // the first non-matching bit and use that to calculate the total
+ // length of the match.
+ while (s2_ptr <= s2_limit - 4 &&
+ BROTLI_UNALIGNED_LOAD32(s2_ptr) ==
+ BROTLI_UNALIGNED_LOAD32(s1 + matched)) {
+ s2_ptr += 4;
+ matched += 4;
+ }
+ while ((s2_ptr < s2_limit) && (s1[matched] == *s2_ptr)) {
+ ++s2_ptr;
+ ++matched;
+ }
+ return matched;
+}
+#endif
+
+} // namespace brotli
+
+#endif // BROTLI_ENC_FIND_MATCH_LENGTH_H_