> `AbstractStringBuilder.charAt(int)` does bounds check before calling
> `charAt()` (for non-latin Strings):
>
> @Override
> public char charAt(int index) {
> checkIndex(index, count);
> if (isLatin1()) {
> return (char)(value[index] & 0xff);
> }
> return StringUTF16.charAt(value, index);
> }
>
> This can be improved by removing bounds check from ASB.charAt() in favour of
> one in String*.charAt(). This gives slight improvement:
>
> before
> Benchmark Mode Cnt Score Error Units
> StringBuilderCharAtBenchmark.latin avgt 50 2,827 ± 0,024 ns/op
> StringBuilderCharAtBenchmark.utf avgt 50 2,985 ± 0,020 ns/op
>
> after
> Benchmark Mode Cnt Score Error Units
> StringBuilderCharAtBenchmark.latin avgt 50 2,434 ± 0,004 ns/op
> StringBuilderCharAtBenchmark.utf avgt 50 2,631 ± 0,004 ns/op
Сергей Цыпанов has refreshed the contents of this pull request, and previous
commits have been removed. The incremental views will show differences compared
to the previous content of the PR. The pull request contains two new commits
since the last revision:
- Merge branch 'master' into 8270160
# Conflicts:
# src/java.base/share/classes/java/lang/StringLatin1.java
- 8270160: Remove redundant bounds check from AbstractStringBuilder.charAt()
-------------
Changes:
- all: https://git.openjdk.java.net/jdk/pull/4738/files
- new: https://git.openjdk.java.net/jdk/pull/4738/files/9f30e621..b7b01ff4
Webrevs:
- full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4738&range=02
- incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4738&range=01-02
Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
Patch: https://git.openjdk.java.net/jdk/pull/4738.diff
Fetch: git fetch https://git.openjdk.java.net/jdk pull/4738/head:pull/4738
PR: https://git.openjdk.java.net/jdk/pull/4738
