TLA  Line data    Source code

       1                 : // evmone: Fast Ethereum Virtual Machine implementation
       2                 : // Copyright 2023 The evmone Authors.
       3                 : // SPDX-License-Identifier: Apache-2.0
       4                 : 
       5                 : #include "bloom_filter.hpp"
       6                 : #include "state.hpp"
       7                 : 
       8                 : namespace evmone::state
       9                 : {
      10                 : 
      11                 : namespace
      12                 : {
      13                 : /// Adds an entry to the bloom filter.
      14                 : /// based on
      15                 : /// https://ethereum.github.io/execution-specs/autoapi/ethereum/shanghai/bloom/index.html#add-to-bloom
      16 UBC           0 : inline void add_to(BloomFilter& bf, const bytes_view& entry)
      17                 : {
      18               0 :     const auto hash = keccak256(entry);
      19                 : 
      20                 :     // take the least significant 11-bits of the first three 16-bit values
      21               0 :     for (const auto i : {0, 2, 4})
      22                 :     {
      23               0 :         const auto bit_to_set = ((hash.bytes[i] & 0x07) << 8) | hash.bytes[i + 1];
      24               0 :         const auto bit_index = 0x07FF - bit_to_set;
      25               0 :         const auto byte_index = bit_index / 8;
      26               0 :         const auto bit_pos = static_cast<uint8_t>(1 << (7 - (bit_index % 8)));
      27               0 :         bf.bytes[byte_index] |= bit_pos;
      28                 :     }
      29               0 : }
      30                 : 
      31                 : }  // namespace
      32                 : 
      33 CBC          53 : BloomFilter compute_bloom_filter(std::span<const Log> logs) noexcept
      34                 : {
      35              53 :     BloomFilter res;
      36              53 :     for (const auto& log : logs)
      37                 :     {
      38 UBC           0 :         add_to(res, log.addr);
      39               0 :         for (const auto& topic : log.topics)
      40               0 :             add_to(res, topic);
      41                 :     }
      42                 : 
      43 CBC          53 :     return res;
      44                 : }
      45                 : 
      46              53 : BloomFilter compute_bloom_filter(std::span<const TransactionReceipt> receipts) noexcept
      47                 : {
      48              53 :     BloomFilter res;
      49                 : 
      50             106 :     for (const auto& r : receipts)
      51              53 :         std::transform(
      52              53 :             res.bytes, std::end(res.bytes), r.logs_bloom_filter.bytes, res.bytes, std::bit_or<>());
      53                 : 
      54              53 :     return res;
      55                 : }
      56                 : 
      57 UBC           0 : BloomFilter bloom_filter_from_bytes(const bytes_view& data) noexcept
      58                 : {
      59               0 :     assert(data.size() == 256);
      60               0 :     BloomFilter res;
      61               0 :     std::copy(std::begin(data), std::end(data), std::begin(res.bytes));
      62               0 :     return res;
      63                 : }
      64                 : 
      65                 : }  // namespace evmone::state