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Diffstat (limited to 'compiler/dwarf/dedup_vector.h')
-rw-r--r-- | compiler/dwarf/dedup_vector.h | 67 |
1 files changed, 0 insertions, 67 deletions
diff --git a/compiler/dwarf/dedup_vector.h b/compiler/dwarf/dedup_vector.h deleted file mode 100644 index 7fb21b76e2..0000000000 --- a/compiler/dwarf/dedup_vector.h +++ /dev/null @@ -1,67 +0,0 @@ -/* - * Copyright (C) 2015 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#ifndef ART_COMPILER_DWARF_DEDUP_VECTOR_H_ -#define ART_COMPILER_DWARF_DEDUP_VECTOR_H_ - -#include <vector> -#include <unordered_map> - -namespace art { -namespace dwarf { - class DedupVector { - public: - // Returns an offset to previously inserted identical block of data, - // or appends the data at the end of the vector and returns offset to it. - size_t Insert(const uint8_t* ptr, size_t num_bytes) { - // See http://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function - uint32_t hash = 2166136261u; - for (size_t i = 0; i < num_bytes; i++) { - hash = (hash ^ ptr[i]) * 16777619u; - } - // Try to find existing copy of the data. - const auto& range = hash_to_offset_.equal_range(hash); - for (auto it = range.first; it != range.second; ++it) { - const size_t offset = it->second; - if (offset + num_bytes <= vector_.size() && - memcmp(vector_.data() + offset, ptr, num_bytes) == 0) { - return offset; - } - } - // Append the data at the end of the vector. - const size_t new_offset = vector_.size(); - hash_to_offset_.emplace(hash, new_offset); - vector_.insert(vector_.end(), ptr, ptr + num_bytes); - return new_offset; - } - - const std::vector<uint8_t>& Data() const { return vector_; } - - private: - struct IdentityHash { - size_t operator()(uint32_t v) const { return v; } - }; - - // We store the full hash as the key to simplify growing of the table. - // It avoids storing or referencing the actual data in the hash-table. - std::unordered_multimap<uint32_t, size_t, IdentityHash> hash_to_offset_; - - std::vector<uint8_t> vector_; - }; -} // namespace dwarf -} // namespace art - -#endif // ART_COMPILER_DWARF_DEDUP_VECTOR_H_ |