This patch optimizes the code paths exercised by
`String.class.getResource("String.class")` by:
- Adding an ASCII fast-path to methods verifying strings in the jimage, which
can then be done allocation-free
- Avoiding the allocation of the `long[8]` attributes when verifying only for
the purpose of verifying a path exists
- Using the `JNUA.create` fast-path in `SystemModuleReader` (which should be OK
since we just verified the given name is a JRT path)
- Remove a redundant check in `Class::resolveName` and fitting the
`StringBuilder` to size
-------------
Commit messages:
- Remove more redundant checks
- More cleanups, remove redundant null checks, synchronization
- Minor cleanup, remove some code duplication
- Fix offsets to properly find extension-less resources (ModuleReaderTest etc)
- Merge branch 'master' into jrt_getString
- Make ImageLocation lookup mostly allocation-free, use JNUA.create in
SystemModuleReader, improve Class.resolveName
- Invert length for non-ASCII case
- Add working micro, cleanup and fix code
- Improve jimage string reading
Changes: https://git.openjdk.java.net/jdk/pull/2212/files
Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2212&range=00
Issue: https://bugs.openjdk.java.net/browse/JDK-8260337
Stats: 387 lines in 8 files changed: 263 ins; 63 del; 61 mod
Patch: https://git.openjdk.java.net/jdk/pull/2212.diff
Fetch: git fetch https://git.openjdk.java.net/jdk pull/2212/head:pull/2212
PR: https://git.openjdk.java.net/jdk/pull/2212
