On Tuesday, 24 July 2012 at 22:19:07 UTC, Jonathan M Davis wrote:
On Tuesday, July 24, 2012 15:49:38 Nick Sabalausky wrote:
Yea. Programs using Goldie ( semitwist.com/goldie ) take a
long time to
compile (by D standards, not by C++ standards). I tried to
benchmark
it a while back, and was never really confident in the results
I was
getting or my understanding of the DMD source, so I never
brought it up
before. But it *seemed* to be template matching that was the
big
bottleneck (ie, IIUC, determining which template to
instantiate,
and I think the function was actually called "match" or
something like
that). Goldie does make use of a *lot* of that sort of thing.
I don't have any hard evidence for it, but I've always gotten
the impression
that it was templates, mixins, and CTFE which really slowed
down compilation.
Certainly, they increase the memory consumption of the compiler
by quite a
bit. My guess would be that if we were looking to improve the
compiler's
performance, that's where we'd need to focus. But we'd have to
actually profile
the compiler on a variety of projects to be sure of that (which
is at least
partially related to what Andrei is suggesting).
- Jonathan M Davis
There's also the nasty O(n^2) optimiser issue.
http://d.puremagic.com/issues/show_bug.cgi?id=7157
