PATCH: change template info representation in g++
Wed Apr 19 18:58:00 GMT 2006
On Apr 18, 2006, at 6:12 PM, Sandra Loosemore wrote:
> I have been commissioned
We don't usually talk about money here... :-)
> to hack on some memory usage improvements in gcc, in particular
> replacing uses of TREE_LIST for things that aren't really lists
> with more compact data structures.
Patch looks good.
A couple of questions... What does it do for compile times (say,
compiling QT or something of that ilk) on a release style-checking -
O2 built compiler? My reading of it is that it should be about the
same speed, but, I do wonder if it is.
Also, what's the change in total memory allocated and/or peak memory
in use? You can use:
--enable-gather-detailed-mem-stats enable detailed memory
allocation stats gathering
and compile with -Q as I recall to get the memory information. Off-
hand, it looks to be about a 50% savings in memory on the
datastructure, though, you can get it to 75% savings if you can move
the single bit for pending_template out into struct lang_type_class
and struct lang_decl_flags.
I do wonder if it is more profitable to just move all the data into
the parent structure and do away with the extra pointer entirely.
Did you consider or try that?
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