RFR: 8289908: Skip bounds check for cases when String is constructed from entirely used byte[] [v3]

[Сергей Цыпанов]

> We can skip bounds check and null check for Charset in case we use the array entirely and the Charset is either default one or proven to be non-null.
> 
> Benchmark results:
> 
> before
> 
> Benchmark                                                  Mode  Cnt  Score   Error  Units
> StringConstructor.newStringFromArray                       avgt   50  4,815 ± 0,154  ns/op
> StringConstructor.newStringFromArrayWithCharset            avgt   50  4,462 ± 0,068  ns/op
> StringConstructor.newStringFromArrayWithCharsetName        avgt   50  8,653 ± 0,040  ns/op
> StringConstructor.newStringFromRangedArray                 avgt   50  5,090 ± 0,066  ns/op
> StringConstructor.newStringFromRangedArrayWithCharset      avgt   50  4,550 ± 0,041  ns/op
> StringConstructor.newStringFromRangedArrayWithCharsetName  avgt   50  8,080 ± 0,055  ns/op
> 
> after
> 
> Benchmark                                                  Mode  Cnt  Score   Error  Units
> StringConstructor.newStringFromArray                       avgt   50  4,595 ± 0,053  ns/op
> StringConstructor.newStringFromArrayWithCharset            avgt   50  4,038 ± 0,062  ns/op
> StringConstructor.newStringFromArrayWithCharsetName        avgt   50  8,035 ± 0,031  ns/op
> StringConstructor.newStringFromRangedArray                 avgt   50  4,084 ± 0,007  ns/op
> StringConstructor.newStringFromRangedArrayWithCharset      avgt   50  4,014 ± 0,008  ns/op
> StringConstructor.newStringFromRangedArrayWithCharsetName  avgt   50  7,466 ± 0,071  ns/op

Сергей Цыпанов has updated the pull request incrementally with one additional commit since the last revision:

  8289908: Fixed tests

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/9407/files
  - new: https://git.openjdk.org/jdk/pull/9407/files/294e91f7..b7375cd3

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9407&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9407&range=01-02

  Stats: 6 lines in 1 file changed: 1 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/9407.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9407/head:pull/9407

PR: https://git.openjdk.org/jdk/pull/9407