archive/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2025-08-27 06:45:07 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

8231717: Improve performance of charset decoding when charset is always compactable

Browse source 
Reviewed-by: rriggs, redestad, alanb
This commit is contained in:
Andrew Leonard 2019-10-10 10:28:55 +01:00
parent 4ad3d82c76
commit 0dbfc97c05
5 changed files with 66 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

15
src/java.base/share/classes/java/lang/StringCoding.java
View file

@ -1,5 +1,5 @@
/*
* Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2000, 2019, 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
@ -191,6 +191,12 @@ class StringCoding {
return result.with(StringLatin1.inflate(ba, off, len), UTF16);
}
}
// fastpath for always Latin1 decodable single byte
if (COMPACT_STRINGS && cd instanceof ArrayDecoder && ((ArrayDecoder)cd).isLatin1Decodable()) {
byte[] dst = new byte[len];
((ArrayDecoder)cd).decodeToLatin1(ba, off, len, dst);
return result.with(dst, LATIN1);
}
int en = scale(len, cd.maxCharsPerByte());
char[] ca = new char[en];
if (cd instanceof ArrayDecoder) {
@ -278,6 +284,13 @@ class StringCoding {
((ArrayDecoder)cd).isASCIICompatible() && !hasNegatives(ba, off, len)) {
return decodeLatin1(ba, off, len);
}
// fastpath for always Latin1 decodable single byte
if (COMPACT_STRINGS && cd instanceof ArrayDecoder && ((ArrayDecoder)cd).isLatin1Decodable()) {
byte[] dst = new byte[len];
((ArrayDecoder)cd).decodeToLatin1(ba, off, len, dst);
return new Result().with(dst, LATIN1);
}
int en = scale(len, cd.maxCharsPerByte());
if (len == 0) {
return new Result().with();