> This resolves minor inefficiency in the fast-path for decoding latin-1 chars > from UTF-8. I also took the opportunity to refactor the StringDecode > microbenchmark to align with recent changes to the StringEncode micro. > > The inefficiency is that this test is quite branchy: > > `if ((b1 == (byte)0xc2 || b1 == (byte)0xc3) && ...` > > Since the two constant bytes differ only on the lowest bit this can be > transformed to this, saving us a branch: > > `if ((b1 & 0xfe) == 0xc2 && ...` > > This provides a small speed-up on microbenchmarks where the input can be > internally encoded as latin1: > > > Benchmark (charsetName) Mode Cnt Score Error Units > StringDecode.decodeLatin1LongStart UTF-8 avgt 50 2283.591 ± 12.332 ns/op > > StringDecode.decodeLatin1LongStart UTF-8 avgt 50 2165.984 ± 13.136 ns/op
Claes Redestad has updated the pull request incrementally with one additional commit since the last revision: Rename and reorder latin1 micro ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/7122/files - new: https://git.openjdk.java.net/jdk/pull/7122/files/926c32bf..e4b6c40a Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7122&range=01 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7122&range=00-01 Stats: 10 lines in 1 file changed: 5 ins; 5 del; 0 mod Patch: https://git.openjdk.java.net/jdk/pull/7122.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/7122/head:pull/7122 PR: https://git.openjdk.java.net/jdk/pull/7122
