8332826: Make hashCode methods in ArraysSupport friendlier

Reviewed-by: redestad, liach
This commit is contained in:
Pavel Rappo 2024-05-30 09:33:30 +00:00
parent 2b4a4b7bd8
commit 3cff588a31
13 changed files with 234 additions and 80 deletions

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2010, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2010, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -113,7 +113,7 @@ class CharacterName {
}
private static int hashN(byte[] a, int off, int len) {
return ArraysSupport.vectorizedHashCode(a, off, len, 1, ArraysSupport.T_BYTE);
return ArraysSupport.hashCode(a, off, len, 1);
}
private int addCp(int idx, int hash, int next, int cp) {

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2015, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2015, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -303,11 +303,7 @@ final class StringLatin1 {
}
public static int hashCode(byte[] value) {
return switch (value.length) {
case 0 -> 0;
case 1 -> value[0] & 0xff;
default -> ArraysSupport.vectorizedHashCode(value, 0, value.length, 0, ArraysSupport.T_BOOLEAN);
};
return ArraysSupport.hashCodeOfUnsigned(value, 0, value.length, 0);
}
// Caller must ensure that from- and toIndex are within bounds

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@ -585,11 +585,7 @@ final class StringUTF16 {
}
public static int hashCode(byte[] value) {
return switch (value.length) {
case 0 -> 0;
case 2 -> getChar(value, 0);
default -> ArraysSupport.vectorizedHashCode(value, 0, value.length >> 1, 0, ArraysSupport.T_CHAR);
};
return ArraysSupport.hashCodeOfUTF16(value, 0, value.length >> 1, 0);
}
// Caller must ensure that from- and toIndex are within bounds

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@ -4098,8 +4098,7 @@ public class BigInteger extends Number implements Comparable<BigInteger> {
*/
@Override
public int hashCode() {
return ArraysSupport.vectorizedHashCode(mag, 0, mag.length, 0,
ArraysSupport.T_INT) * signum;
return ArraysSupport.hashCode(mag, 0, mag.length, 0) * signum;
}
/**

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2000, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2000, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -707,7 +707,7 @@ class Heap$Type$Buffer$RW$
}
public int hashCode() {
return ArraysSupport.vectorizedHashCode(hb, ix(position()), remaining(), 1, ArraysSupport.T_BYTE);
return ArraysSupport.hashCode(hb, ix(position()), remaining(), 1);
}
#end[byte]
@ -738,7 +738,7 @@ class Heap$Type$Buffer$RW$
}
public int hashCode() {
return ArraysSupport.vectorizedHashCode(hb, ix(position()), remaining(), 1, ArraysSupport.T_CHAR);
return ArraysSupport.hashCode(hb, ix(position()), remaining(), 1);
}
#end[char]

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@ -1,5 +1,5 @@
/*
* Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -4358,11 +4358,7 @@ public final class Arrays {
if (a == null) {
return 0;
}
return switch (a.length) {
case 0 -> 1;
case 1 -> 31 + a[0];
default -> ArraysSupport.vectorizedHashCode(a, 0, a.length, 1, ArraysSupport.T_INT);
};
return ArraysSupport.hashCode(a, 0, a.length, 1);
}
/**
@ -4385,11 +4381,7 @@ public final class Arrays {
if (a == null) {
return 0;
}
return switch (a.length) {
case 0 -> 1;
case 1 -> 31 + (int)a[0];
default -> ArraysSupport.vectorizedHashCode(a, 0, a.length, 1, ArraysSupport.T_SHORT);
};
return ArraysSupport.hashCode(a, 0, a.length, 1);
}
/**
@ -4412,11 +4404,7 @@ public final class Arrays {
if (a == null) {
return 0;
}
return switch (a.length) {
case 0 -> 1;
case 1 -> 31 + (int)a[0];
default -> ArraysSupport.vectorizedHashCode(a, 0, a.length, 1, ArraysSupport.T_CHAR);
};
return ArraysSupport.hashCode(a, 0, a.length, 1);
}
/**
@ -4439,11 +4427,7 @@ public final class Arrays {
if (a == null) {
return 0;
}
return switch (a.length) {
case 0 -> 1;
case 1 -> 31 + (int)a[0];
default -> ArraysSupport.vectorizedHashCode(a, 0, a.length, 1, ArraysSupport.T_BYTE);
};
return ArraysSupport.hashCode(a, 0, a.length, 1);
}
/**
@ -4549,15 +4533,10 @@ public final class Arrays {
* @since 1.5
*/
public static int hashCode(Object[] a) {
if (a == null)
if (a == null) {
return 0;
int result = 1;
for (Object element : a)
result = 31 * result + Objects.hashCode(element);
return result;
}
return ArraysSupport.hashCode(a, 0, a.length, 1);
}
/**

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@ -290,8 +290,7 @@ class ZipCoder {
// exceptions eagerly when opening ZipFiles
return hash(JLA.newStringUTF8NoRepl(a, off, len));
}
// T_BOOLEAN to treat the array as unsigned bytes, in line with StringLatin1.hashCode
int h = ArraysSupport.vectorizedHashCode(a, off, len, 0, ArraysSupport.T_BOOLEAN);
int h = ArraysSupport.hashCodeOfUnsigned(a, off, len, 0);
if (a[end - 1] != '/') {
h = 31 * h + '/';
}

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2022, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -230,7 +230,7 @@ public abstract sealed class AbstractPoolEntry {
*/
private void inflate() {
int singleBytes = JLA.countPositives(rawBytes, offset, rawLen);
int hash = ArraysSupport.vectorizedHashCode(rawBytes, offset, singleBytes, 0, ArraysSupport.T_BOOLEAN);
int hash = ArraysSupport.hashCodeOfUnsigned(rawBytes, offset, singleBytes, 0);
if (singleBytes == rawLen) {
this.hash = hashString(hash);
charLen = rawLen;

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@ -26,6 +26,8 @@ package jdk.internal.util;
import java.util.Arrays;
import java.util.Collection;
import java.util.Objects;
import jdk.internal.access.JavaLangAccess;
import jdk.internal.access.SharedSecrets;
import jdk.internal.misc.Unsafe;
@ -164,17 +166,177 @@ public class ArraysSupport {
}
}
/**
* Calculates the hash code for the subrange of an integer array.
*
* <p> This method does not perform type checks or bounds checks. It is the
* responsibility of the caller to perform such checks before calling this
* method.
*
* @param a the array
* @param fromIndex the first index of the subrange of the array
* @param length the number of elements in the subrange
* @param initialValue the initial hash value, typically 0 or 1
*
* @return the calculated hash value
*/
public static int hashCode(int[] a, int fromIndex, int length, int initialValue) {
return switch (length) {
case 0 -> initialValue;
case 1 -> 31 * initialValue + a[fromIndex];
default -> vectorizedHashCode(a, fromIndex, length, initialValue, T_INT);
};
}
/**
* Calculates the hash code for the subrange of a short array.
*
* <p> This method does not perform type checks or bounds checks. It is the
* responsibility of the caller to perform such checks before calling this
* method.
*
* @param a the array
* @param fromIndex the first index of the subrange of the array
* @param length the number of elements in the subrange
* @param initialValue the initial hash value, typically 0 or 1
*
* @return the calculated hash value
*/
public static int hashCode(short[] a, int fromIndex, int length, int initialValue) {
return switch (length) {
case 0 -> initialValue;
case 1 -> 31 * initialValue + a[fromIndex];
default -> vectorizedHashCode(a, fromIndex, length, initialValue, T_SHORT);
};
}
/**
* Calculates the hash code for the subrange of a char array.
*
* <p> This method does not perform type checks or bounds checks. It is the
* responsibility of the caller to perform such checks before calling this
* method.
*
* @param a the array
* @param fromIndex the first index of the subrange of the array
* @param length the number of elements in the subrange
* @param initialValue the initial hash value, typically 0 or 1
*
* @return the calculated hash value
*/
public static int hashCode(char[] a, int fromIndex, int length, int initialValue) {
return switch (length) {
case 0 -> initialValue;
case 1 -> 31 * initialValue + a[fromIndex];
default -> vectorizedHashCode(a, fromIndex, length, initialValue, T_CHAR);
};
}
/**
* Calculates the hash code for the subrange of a byte array.
*
* <p> This method does not perform type checks or bounds checks. It is the
* responsibility of the caller to perform such checks before calling this
* method.
*
* @param a the array
* @param fromIndex the first index of the subrange of the array
* @param length the number of elements in the subrange
* @param initialValue the initial hash value, typically 0 or 1
*
* @return the calculated hash value
*/
public static int hashCode(byte[] a, int fromIndex, int length, int initialValue) {
return switch (length) {
case 0 -> initialValue;
case 1 -> 31 * initialValue + a[fromIndex];
default -> vectorizedHashCode(a, fromIndex, length, initialValue, T_BYTE);
};
}
/**
* Calculates the hash code for the subrange of a byte array whose elements
* are treated as unsigned bytes.
*
* <p> This method does not perform type checks or bounds checks. It is the
* responsibility of the caller to perform such checks before calling this
* method.
*
* @param a the array
* @param fromIndex the first index of the subrange of the array
* @param length the number of elements in the subrange
* @param initialValue the initial hash value, typically 0 or 1
*
* @return the calculated hash value
*/
public static int hashCodeOfUnsigned(byte[] a, int fromIndex, int length, int initialValue) {
return switch (length) {
case 0 -> initialValue;
case 1 -> 31 * initialValue + Byte.toUnsignedInt(a[fromIndex]);
default -> vectorizedHashCode(a, fromIndex, length, initialValue, T_BOOLEAN);
};
}
/**
* Calculates the hash code for the subrange of a byte array whose contents
* are treated as UTF-16 chars.
*
* <p> This method does not perform type checks or bounds checks. It is the
* responsibility of the caller to perform such checks before calling this
* method.
*
* <p> {@code fromIndex} and {@code length} must be scaled down to char
* indexes.
*
* @param a the array
* @param fromIndex the first index of a char in the subrange of the array
* @param length the number of chars in the subrange
* @param initialValue the initial hash value, typically 0 or 1
*
* @return the calculated hash value
*/
public static int hashCodeOfUTF16(byte[] a, int fromIndex, int length, int initialValue) {
return switch (length) {
case 0 -> initialValue;
case 1 -> 31 * initialValue + JLA.getUTF16Char(a, fromIndex);
default -> vectorizedHashCode(a, fromIndex, length, initialValue, T_CHAR);
};
}
/**
* Calculates the hash code for the subrange of an object array.
*
* <p> This method does not perform type checks or bounds checks. It is the
* responsibility of the caller to perform such checks before calling this
* method.
*
* @param a the array
* @param fromIndex the first index of the subrange of the array
* @param length the number of elements in the subrange
* @param initialValue the initial hash value, typically 0 or 1
*
* @return the calculated hash value
*/
public static int hashCode(Object[] a, int fromIndex, int length, int initialValue) {
int result = initialValue;
int end = fromIndex + length;
for (int i = fromIndex; i < end; i++) {
result = 31 * result + Objects.hashCode(a[i]);
}
return result;
}
// Possible values for the type operand of the NEWARRAY instruction.
// See https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-6.html#jvms-6.5.newarray.
public static final int T_BOOLEAN = 4;
public static final int T_CHAR = 5;
public static final int T_FLOAT = 6;
public static final int T_DOUBLE = 7;
public static final int T_BYTE = 8;
public static final int T_SHORT = 9;
public static final int T_INT = 10;
public static final int T_LONG = 11;
private static final int T_BOOLEAN = 4;
private static final int T_CHAR = 5;
private static final int T_FLOAT = 6;
private static final int T_DOUBLE = 7;
private static final int T_BYTE = 8;
private static final int T_SHORT = 9;
private static final int T_INT = 10;
private static final int T_LONG = 11;
/**
* Calculate the hash code for an array in a way that enables efficient
@ -197,8 +359,8 @@ public class ArraysSupport {
* @return the calculated hash value
*/
@IntrinsicCandidate
public static int vectorizedHashCode(Object array, int fromIndex, int length, int initialValue,
int basicType) {
private static int vectorizedHashCode(Object array, int fromIndex, int length, int initialValue,
int basicType) {
return switch (basicType) {
case T_BOOLEAN -> unsignedHashCode(initialValue, (byte[]) array, fromIndex, length);
case T_CHAR -> array instanceof byte[]
@ -214,7 +376,7 @@ public class ArraysSupport {
private static int unsignedHashCode(int result, byte[] a, int fromIndex, int length) {
int end = fromIndex + length;
for (int i = fromIndex; i < end; i++) {
result = 31 * result + (a[i] & 0xff);
result = 31 * result + Byte.toUnsignedInt(a[i]);
}
return result;
}
@ -255,7 +417,7 @@ public class ArraysSupport {
/*
* fromIndex and length must be scaled to char indexes.
*/
public static int utf16hashCode(int result, byte[] value, int fromIndex, int length) {
private static int utf16hashCode(int result, byte[] value, int fromIndex, int length) {
int end = fromIndex + length;
for (int i = fromIndex; i < end; i++) {
result = 31 * result + JLA.getUTF16Char(value, i);

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@ -1,5 +1,5 @@
/*
* Copyright (c) 1996, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 1996, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -1267,7 +1267,7 @@ public class DerValue {
*/
@Override
public int hashCode() {
return ArraysSupport.vectorizedHashCode(buffer, start, end - start, tag, ArraysSupport.T_BYTE);
return ArraysSupport.hashCode(buffer, start, end - start, tag);
}
/**