LLVM IR influence on compiler debugging

[Jonathan M Davis]

On Saturday, July 07, 2012 16:54:48 Adam Wilson wrote:
> On Sat, 07 Jul 2012 16:38:27 -0700, Timon Gehr <timon.gehr at gmx.ch> wrote:
> > The DMD backend is very fast in comparison to other backends.
> > 
> > LLVM is unlikely to catch up in speed, because it is well architectured
> > and more general.
> 
> Oh, I agree that it is, but as I've been saying, raw compiler speed is
> rarely an important factor outside of small circles of developers, if it
> was, businesses would have given up on C++ LONG ago. It's nice to have,
> but the business case for it is weak comparatively.

Just because one set of developers has priorities other than compilation speed 
which they consider to be more important doesn't mean that a lot of developers 
don't think that compilation speed is important. I've worked on projects that 
took over 3 hours to build but that doesn't mean that I wouldn't have wanted 
them to be faster. I've known programmers who complained about builds which 
were over a minute!

If you rate something else higher than compilation speed, that's fine, but that 
doesn't mean that compilation speed doesn't matter, because it does.

And if the various D Compilers are consistent enough, it arguably becomes a 
good course of action to build your ultimate release using gdc or ldc but to 
do most of the direct development on dmd so that you get a fast compile-test-
rewrite cycle.

- Jonathan M Davis