LWN.net Logo

Request for testing/help for the LTO branch

From:  Diego Novillo <dnovillo-AT-google.com>
To:  gcc-AT-gcc.gnu.org
Subject:  Request for testing/help for the LTO branch
Date:  Tue, 27 Jan 2009 16:11:20 -0500
Message-ID:  <b798aad50901271311u2e5b18a7pb4767c9ea196c3be@mail.gmail.com>
Cc:  Rafael Espindola <espindola-AT-google.com>, Simon Baldwin <simonb-AT-google.com>, Doug Kwan <dougkwan-AT-google.com>, Cary Coutant <ccoutant-AT-google.com>
Archive-link:  Article, Thread

The LTO branch is starting to get some semblance of stability, though
is by no means in any kind of mergeable state.  I have updated the
wiki page to reflect the current status (Simon, Rafael, Doug, Cary,
please make sure I haven't missed anything substantial):

http://gcc.gnu.org/wiki/LinkTimeOptimization

Essentially, the biggest areas where we need help are:

- Testing on other targets.  We have only tested on x86 (32 and 64
bit) targets.  I'm pretty sure other targets are either non-functional
or show major breakage.  We'd appreciate any daily tester that could
include the branch and report bugs to bugzilla (feel free to assign to
me).

- Help with testsuite regressions.  There are currently around 1,200
regressions vs mainline.  Some may not even be too gruesome to fix.
We are currently testing the code with a set of internal large
applications, which is what has been driving our patches, some times
fixes we do happen to fix testsuite programs, but not always.

This is a list of major issues that need to be addressed.  The wiki
page contains full details:

* Re-implement the GIMPLE streamer
* -v -save-temps does not always show everything needed to reproduce a
compilation stage when using -fwhopr
* -fwhopr should not launch the LTRANS phase from lto1
* WPA should use the pass manager
* Design and implement rules for handling mixed command line options.
* Browsing/dumping tools for LTO files
* Implement a GIMPLE type system
* Read GIMPLE from a text file
* Improve serialization
* Make nested functions work properly
* Fix debug information for LTO programs
* Test on other platforms
* Aliasing information needs to be propagated all the way through LTO


Thanks.  Diego.



(Log in to post comments)

Copyright © 2009, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds