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/** 
 * Licensed to the Apache Software Foundation (ASF) under one 
 * or more contributor license agreements.  See the NOTICE file 
 * distributed with this work for additional information 
 * regarding copyright ownership.  The ASF licenses this file 
 * to you 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. 
 */ 
 
#include "Adaptor.hh" 
#include "Murmur3.hh" 
 
#define ROTL64(x, r) ((x << r) | (x >> (64 - r))) 
 
namespace orc { 
 
  inline uint64_t rotl64 ( uint64_t x, int8_t r ) { 
    return (x << r) | (x >> (64 - r)); 
  } 
 
  inline uint64_t Murmur3::fmix64(uint64_t value) { 
    value ^= (value >> 33); 
    value *= 0xff51afd7ed558ccdL; 
    value ^= (value >> 33); 
    value *= 0xc4ceb9fe1a85ec53L; 
    value ^= (value >> 33); 
    return value; 
  } 
 
  uint64_t Murmur3::hash64(const uint8_t *data, uint32_t len) { 
    return hash64(data, len, DEFAULT_SEED); 
  } 
 
  DIAGNOSTIC_PUSH 
 
#if defined(__clang__) 
    DIAGNOSTIC_IGNORE("-Wimplicit-fallthrough") 
#endif 
 
  uint64_t Murmur3::hash64(const uint8_t *data, uint32_t len, uint32_t seed) { 
    uint64_t h = seed; 
    uint32_t blocks = len >> 3; 
 
    const uint64_t* src = reinterpret_cast<const uint64_t*>(data); 
    uint64_t c1 = 0x87c37b91114253d5L; 
    uint64_t c2 = 0x4cf5ad432745937fL; 
    for (uint32_t i = 0; i < blocks; i++) { 
      uint64_t k = src[i]; 
      k *= c1; 
      k = ROTL64(k, 31); 
      k *= c2; 
 
      h ^= k; 
      h = ROTL64(h, 27); 
      h = h * 5 + 0x52dce729; 
    } 
 
    uint64_t k = 0; 
    uint32_t idx = blocks << 3; 
    switch (len - idx) { 
      case 7: 
        k ^= static_cast<uint64_t>(data[idx + 6]) << 48; 
      case 6: 
        k ^= static_cast<uint64_t>(data[idx + 5]) << 40; 
      case 5: 
        k ^= static_cast<uint64_t>(data[idx + 4]) << 32; 
      case 4: 
        k ^= static_cast<uint64_t>(data[idx + 3]) << 24; 
      case 3: 
        k ^= static_cast<uint64_t>(data[idx + 2]) << 16; 
      case 2: 
        k ^= static_cast<uint64_t>(data[idx + 1]) << 8; 
      case 1: 
        k ^= static_cast<uint64_t>(data[idx + 0]); 
 
        k *= c1; 
        k = ROTL64(k, 31); 
        k *= c2; 
        h ^= k; 
    } 
 
    h ^= len; 
    h = fmix64(h); 
    return h; 
  } 
 
  DIAGNOSTIC_POP 
 
}