Bug 78321 - Fission + type units + compression are suboptimal
Summary: Fission + type units + compression are suboptimal
Status: UNCONFIRMED
Alias: None
Product: gcc
Classification: Unclassified
Component: debug (show other bugs)
Version: 6.1.0
: P3 normal
Target Milestone: ---
Assignee: Not yet assigned to anyone
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Reported: 2016-11-11 18:20 UTC by David Blaikie
Modified: 2017-01-26 15:54 UTC (History)
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Description David Blaikie 2016-11-11 18:20:19 UTC
GCC is producing separate (though non-comdat) sections for each type in the .dwo file when using fission+type units.

There's no need for these to be in separate sections - and it hurts compression greatly. (this may be one of the reasons Clang's .debug_types.dwo section is 1/6th the size of GCC's in a large example at Google)

It may make merging types a little more efficient - by not having to decompress the whole set of types to merge in just one/a few types, so there's potentially a memory/storage tradeoff here.
Comment 1 David Blaikie 2017-01-26 15:54:20 UTC
ping