jpountz commented on a change in pull request #541: URL: https://github.com/apache/lucene/pull/541#discussion_r783744532
########## File path: lucene/core/src/java/org/apache/lucene/util/bkd/BKDForUtil.java ########## @@ -0,0 +1,88 @@ +// This file has been automatically generated, DO NOT EDIT +/* + * 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. + */ +package org.apache.lucene.util.bkd; + +import java.io.IOException; +import org.apache.lucene.store.DataInput; +import org.apache.lucene.store.DataOutput; + +// Inspired from https://fulmicoton.com/posts/bitpacking/ +// Encodes multiple integers in a long to get SIMD-like speedups. +// If bitsPerValue <= 8 then we pack 8 ints per long +// else if bitsPerValue <= 16 we pack 4 ints per long +// else we pack 2 ints per long Review comment: this comment is no longer relevant ########## File path: lucene/core/src/java/org/apache/lucene/util/bkd/DocIdsWriter.java ########## @@ -24,58 +24,94 @@ import org.apache.lucene.util.DocBaseBitSetIterator; import org.apache.lucene.util.FixedBitSet; -class DocIdsWriter { +final class DocIdsWriter { - private DocIdsWriter() {} + private static final byte CONTINUOUS_IDS = (byte) -2; + private static final byte BITSET_IDS = (byte) -1; + private static final byte DELTA_VINT = (byte) 0; + private static final byte DELTA_FOR_UTIL = (byte) 32 + 16; + private static final byte BPV_24 = (byte) 24; + private static final byte BPV_24_FOR_UTIL = (byte) 32 + 24; + private static final byte BPV_32 = (byte) 32; + private static final byte BPV_32_FOR_UTIL = (byte) 32 + 32; Review comment: do BPV_32 and BPV_32_FOR_UTIL encode data the same way? If yes, could we combine them? ########## File path: lucene/core/src/java/org/apache/lucene/util/bkd/DocIdsWriter.java ########## @@ -24,58 +24,94 @@ import org.apache.lucene.util.DocBaseBitSetIterator; import org.apache.lucene.util.FixedBitSet; -class DocIdsWriter { +final class DocIdsWriter { - private DocIdsWriter() {} + private static final byte CONTINUOUS_IDS = (byte) -2; + private static final byte BITSET_IDS = (byte) -1; + private static final byte DELTA_VINT = (byte) 0; + private static final byte DELTA_FOR_UTIL = (byte) 32 + 16; + private static final byte BPV_24 = (byte) 24; + private static final byte BPV_24_FOR_UTIL = (byte) 32 + 24; Review comment: maybe call them LEGACY_BPV_24 and BPV_24 instead to make it clear which one is the right one -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org
