On 25.12.2012 19:30, Dimitri Smits wrote:
----- Oorspronkelijk e-mail -----
Van: "Florian Klaempfl" <flor...@freepascal.org>
Aan: "FPC developers' list" <fpc-devel@lists.freepascal.org>
Verzonden: Dinsdag 25 december 2012 14:15:24
Onderwerp: Re: [fpc-devel] Forwarded message about FPC status
I see no way to speed up the 2.x FPC significantly only by stripping
something down or whatever. The whole 2.x design is geared towards
portability and maintainability, speed is only 2nd level goal (and
being
honest, self compilation in ~10 sec even on my >5 year old Core 2 Duo
is
not that bad ;)).
I'm guessing that is NOT on a Windows platform? Every full build (it has been a
while) I've ever done of the compiler on windows was at least a few minutes.
That's likely because of the slower process startup time of Windows.
Also the GNU utilities we use (make, etc.) aren't the fastest on Windows
either. Also command line output can slow down things dramatically
(cmd.exe or the PowerShell aren't that fast).
what I *think* is a large hog on compilation/linking is the spawning of
multiple executables in the different steps as opposed to the monolithic
exe(+dll) that dcc32.exe is.
If you use the internal assembler and linker on Windows you get the same.
The only approach I see to speed it up is to kick the whole back end
and
generate directly some close to i386 intermediate code directly in
the
parser.
lovely, but isn't that what Embarcadero is doing for their future compiler? Using the
llvm toolchain, they will provide a front compiler to an intermediate
"language" or interpreted code. Then they have a few optimisations for the
middle layer and use the back-ends that are already available to make stuff
architecturally compile to whatever back-end (ARM v?, intel x86, powerpc, motorola 68k,
jvm, dalvik, .net il, compiled php, ... or any community or custom backend)
But it is very likely that they won't gain a speed advantage by that.
They need to decouple their frontend from their backend and here it is
very likely that they get a performance penalty if they need to go
through some indirections or callbacks to get the necessary information
from frontend to backend (or they need to stuff all information
potentially needed by the backend into the backend). Basically the same
that FPC does...
Also LLVM does not support that many backends. Currently the most
important ones are x86(_64), ARM and PowerPC. What LLVM definitely does
not support is m68k...
Regards,
Sven
_______________________________________________
fpc-devel maillist - fpc-devel@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-devel
