Problems with dmd inlining

[Brad Roberts]

On 12/11/2010 8:22 PM, Craig Black wrote:
> I did some benchmarking with a simple quick sort algorithm and was very
> disappointed that dmd was over twice as slow as Visual C++.  Investigation
> revealed most of the slowness was due to the fact that dmd was not inlining a
> simple function that returned a reference.  After hand-inlining some code, I got
> within 20% of the performance of Visual C++.  I don't see this as acceptable. 
> The main reason that I want to use D is so that my code will be cleaner.  If I
> have to inline my own functions then this will not result in clean code.
> 
> Anyway, has anyone else had problems with dmd's inliner?  Should I post a bug
> report or has someone else already complained about this?
> 
> -Craig

There's a number of things that currently stop dmd from inlining.  Several exist
as bug reports.  I don't recall if there's one about ref return results or not.
 These limitations are certainly worth working to lift, but they're lower
priority than a lot of other bugs.  That said, they're the sort of thing I enjoy
trying to fix, so go ahead and file a nice tiny test case.

As always, if there's issues you care a lot about, the source code for the
compiler is there for anyone to work with.

Later,
Brad