Sorry, I meant a "repeat... until False;" loop, using "Break" or "Exit"
statements when I actually want to leave it, and "Continue" for the
'not-a-goto' statement!
On 26/10/2019 15:47, J. Gareth Moreton wrote:
Hi Florian,
That seems like a fair assessment. I'll see what I can do, especially
as I have a design spec to go by, so maybe there's stuff to salvage
and re-implement.
If I recall, there was a similar TODO in the current code and it just
got moved, but I'll double-check that.
I've seen 'goto' used a few times in the code but wasn't sure what the
policy was on that. Generally I use a "repeat... until True;" loop
with a "Continue;" - is that an okay substitution?
Since you're suggesting more bite-sized chunks, I think the first
thing I'll do is overhaul the jump optimisations, since they caused
significant improvements in places that are independent of reducing
the optimiser passes.
Gareth aka. Kit
On 26/10/2019 13:26, Florian Klämpfl wrote:
Am 18.10.19 um 18:07 schrieb J. Gareth Moreton:
Hi everyone,
How is everyone doing? Sorry for my silence - been a bit tied up
with things in life. Anyway, that aside, has there been any further
progress on reviewing the x86_64 optimizer overhaul over at
https://bugs.freepascal.org/view.php?id=34628? I ask because I've
sort-of blocked myself in any further improvements to the peephole
optimizer.
I had meanwhile a look at it and to be honest, I am against applying
the remainders in its current form.
- First, the patches are inter-winded and the single patches do not
cover one single topic. Today, using e.g. TortoiseGit on Windows
(sorry, on Linux there is no tool which comes close) such patches can
be re-arranged without too much hazzle.
- Breaking the principle of the multiple optimizer passes is
reasonable on the one hand, on the other hand it makes complicated
code even more complicated and in particular as only the optimizer
benefits, I see no reason to do so. In particular in combination with
using gotos, the price being payed regarding maintainability is very
high.
- Also things like ConditionalJumpShortcut in aoptx86.pas containing
arm and aarch64 defines does not convince me regarding the patches.
- Patches contains open todo: "TODO: FIXME removing the first
instruction fails"
I would really like to see parts of the patch applied, but this
requires that it is re-arranged in small, oversee-able changes.
_______________________________________________
fpc-devel maillist - fpc-devel@lists.freepascal.org
https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
_______________________________________________
fpc-devel maillist - fpc-devel@lists.freepascal.org
https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
