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all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
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/*
* Copyright 2024 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.util.internal;
/**
* Utility class for SWAR (SIMD within a register) operations.
*/
public final class SWARUtil {
/**
* Compiles given byte into a long pattern suitable for SWAR operations.
*/
public static long compilePattern(byte byteToFind) {
return (byteToFind & 0xFFL) * 0x101010101010101L;
}
/**
* Applies a compiled pattern to given word.
* Returns a word where each byte that matches the pattern has the highest bit set.
*
* @param word the word to apply the pattern to
* @param pattern the pattern to apply
* @return a word where each byte that matches the pattern has the highest bit set
*/
public static long applyPattern(final long word, final long pattern) {
long input = word ^ pattern;
long tmp = (input & 0x7F7F7F7F7F7F7F7FL) + 0x7F7F7F7F7F7F7F7FL;
return ~(tmp | input | 0x7F7F7F7F7F7F7F7FL);
}
/**
* Returns the index of the first occurrence of byte that specificied in the pattern.
* If no pattern is found, returns 8.
*
* @param word the return value of {@link #applyPattern(long, long)}
* @param isBigEndian if true, if given word is big endian
* if false, if given word is little endian
* @return the index of the first occurrence of the specified pattern in the specified word.
* If no pattern is found, returns 8.
*/
public static int getIndex(final long word, final boolean isBigEndian) {
final int zeros = isBigEndian? Long.numberOfLeadingZeros(word) : Long.numberOfTrailingZeros(word);
return zeros >>> 3;
}
/**
* Returns a word where each ASCII uppercase byte has the highest bit set.
*/
private static long applyUpperCasePattern(final long word) {
// Inspired by https://github.com/facebook/folly/blob/add4049dd6c2371eac05b92b6fd120fd6dd74df5/folly/String.cpp
long rotated = word & 0x7F7F7F7F7F7F7F7FL;
rotated += 0x2525252525252525L;
rotated &= 0x7F7F7F7F7F7F7F7FL;
rotated += 0x1A1A1A1A1A1A1A1AL;
rotated &= ~word;
rotated &= 0x8080808080808080L;
return rotated;
}
/**
* Returns a word where each ASCII uppercase byte has the highest bit set.
*/
private static int applyUpperCasePattern(final int word) {
int rotated = word & 0x7F7F7F7F;
rotated += 0x25252525;
rotated &= 0x7F7F7F7F;
rotated += 0x1A1A1A1A;
rotated &= ~word;
rotated &= 0x80808080;
return rotated;
}
/**
* Returns a word where each ASCII lowercase byte has the highest bit set.
*/
private static long applyLowerCasePattern(final long word) {
long rotated = word & 0x7F7F7F7F7F7F7F7FL;
rotated += 0x0505050505050505L;
rotated &= 0x7F7F7F7F7F7F7F7FL;
rotated += 0x1A1A1A1A1A1A1A1AL;
rotated &= ~word;
rotated &= 0x8080808080808080L;
return rotated;
}
/**
* Returns a word where each lowercase ASCII byte has the highest bit set.
*/
private static int applyLowerCasePattern(final int word) {
int rotated = word & 0x7F7F7F7F;
rotated += 0x05050505;
rotated &= 0x7F7F7F7F;
rotated += 0x1A1A1A1A;
rotated &= ~word;
rotated &= 0x80808080;
return rotated;
}
/**
* Returns true if the given word contains at least one ASCII uppercase byte.
*/
public static boolean containsUpperCase(final long word) {
return applyUpperCasePattern(word) != 0;
}
/**
* Returns true if the given word contains at least one ASCII uppercase byte.
*/
public static boolean containsUpperCase(final int word) {
return applyUpperCasePattern(word) != 0;
}
/**
* Returns true if the given word contains at least one ASCII lowercase byte.
*/
public static boolean containsLowerCase(final long word) {
return applyLowerCasePattern(word) != 0;
}
/**
* Returns true if the given word contains at least one ASCII lowercase byte.
*/
public static boolean containsLowerCase(final int word) {
return applyLowerCasePattern(word) != 0;
}
/**
* Returns a word with all bytes converted to lowercase ASCII.
*/
public static long toLowerCase(final long word) {
final long mask = applyUpperCasePattern(word) >>> 2;
return word | mask;
}
/**
* Returns a word with all bytes converted to lowercase ASCII.
*/
public static int toLowerCase(final int word) {
final int mask = applyUpperCasePattern(word) >>> 2;
return word | mask;
}
/**
* Returns a word with all bytes converted to uppercase ASCII.
*/
public static long toUpperCase(final long word) {
final long mask = applyLowerCasePattern(word) >>> 2;
return word & ~mask;
}
/**
* Returns a word with all bytes converted to uppercase ASCII.
*/
public static int toUpperCase(final int word) {
final int mask = applyLowerCasePattern(word) >>> 2;
return word & ~mask;
}
private SWARUtil() {
// Utility
}
}