[
https://issues.apache.org/jira/browse/DRILL-1854?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Jacques Nadeau updated DRILL-1854:
----------------------------------
Fix Version/s: Future
> reduce number of local variables in generated operators by reusing them
> -----------------------------------------------------------------------
>
> Key: DRILL-1854
> URL: https://issues.apache.org/jira/browse/DRILL-1854
> Project: Apache Drill
> Issue Type: Improvement
> Components: Execution - Codegen
> Reporter: Chris Westin
> Assignee: Chris Westin
> Fix For: Future
>
>
> Every time code gen inlines a function, it generates new temporaries for it
> to use. The number of locals is getting very large for some functions -- I've
> seen one case with about 300. But all of these locals are only referenced
> within a single block. It appears that the java compiler (at least Janino)
> does not reuse these (compare with a C/C++ compiler, which would reuse the
> same stack space across blocks). We can be smarter about not generating new
> temporaries, and just reusing compatible ones if they are already available
> by maintaining a pool (map of Type to variable name) of available variables,
> and borrowing from these during code generation as necessary.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
