RFR: JDK-8193717: Import resolution performance regression in JDK 9 (original) (raw)

Jan Lahoda jan.lahoda at oracle.com
Mon May 21 11:24:04 UTC 2018

Hi,

A webrev updated to the current situation, and with a comment explaining the need for the HashMap is here (as suggested offline): http://cr.openjdk.java.net/~jlahoda/8193717/webrev.01/

Any feedback is welcome.

Thanks, Jan

On 2.3.2018 17:52, Jan Lahoda wrote:

Hi,

Having a source with a lot of imports can lead to a long compilation time, as the imports are lazily searched on each query to the Scope. But at least for named imports, the name is known, and can be used for quick filtering. (Sadly, for on-demand imports/package imports, this is much more difficult, and this patch does not improve them.) The principle of the patch is to have a map from name to scopes that may contain the given name in Scope.NamedImportScope. Also, the "current-file top-level scope" (JCCompilationUnit.toplevelScope) is no longer appended to the named import scope, but rather the relevant lookup is enhanced to query it as well if needed. This seems cleaner that trying to append the scope to the fast name lookup. Bug: https://bugs.openjdk.java.net/browse/JDK-8193717 Webrev: http://cr.openjdk.java.net/~jlahoda/8193717/webrev.00/ Liam, could you please check if this helps with your real-world case? How does this look? Thanks, Jan

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