github.com/apache/arrow/go/v10@v10.0.1/parquet/internal/bmi/_lib/bitmap_bmi2.c (about)

     1  // Licensed to the Apache Software Foundation (ASF) under one
     2  // or more contributor license agreements.  See the NOTICE file
     3  // distributed with this work for additional information
     4  // regarding copyright ownership.  The ASF licenses this file
     5  // to you under the Apache License, Version 2.0 (the
     6  // "License"); you may not use this file except in compliance
     7  // with the License.  You may obtain a copy of the License at
     8  //
     9  // http://www.apache.org/licenses/LICENSE-2.0
    10  //
    11  // Unless required by applicable law or agreed to in writing, software
    12  // distributed under the License is distributed on an "AS IS" BASIS,
    13  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14  // See the License for the specific language governing permissions and
    15  // limitations under the License.
    16  
    17  #include <arch.h>
    18  #include <stdint.h>
    19  
    20  uint64_t FULL_NAME(extract_bits)(uint64_t bitmap, uint64_t select_bitmap) {
    21  #if defined(__BMI2__)
    22     return (uint64_t)(_pext_u64(bitmap, select_bitmap));
    23  #else
    24    uint64_t res = 0;
    25    for (uint64_t bp = 1; select_bitmap != 0; bp += bp) {
    26      if (bitmap & select_bitmap & -select_bitmap) {
    27        res |= bp;
    28      }
    29      select_bitmap &= (select_bitmap - 1);
    30    }
    31    return res;
    32  #endif
    33  }
    34  
    35  uint64_t FULL_NAME(levels_to_bitmap)(const int16_t* levels, const int num_levels, const int16_t rhs) {
    36    uint64_t mask = 0;
    37    for (int x = 0; x < num_levels; x++) {
    38      mask |= (uint64_t)(levels[x] > rhs ? 1 : 0) << x;
    39    }
    40    return mask;
    41  }