Re: Removing ARCNET stuffs

[Anders Magnusson <ragge%ludd.ltu.se@localhost>]

Andrew Cagney skrev den 2015-06-01 17:41:
> On 1 June 2015 at 02:15, Anders Magnusson <ragge%ludd.ltu.se@localhost> wrote:
> > Andrew Cagney skrev den 2015-06-01 03:24:
> > > systems and generates reasonable code.  Unfortunately, and sorry PCC
> > > (stabs, really?),
> > Feel free to add dwarf, the source is out there, and it wouldn't be
> > especially difficult to do it.  I just haven't had time.
> > Stabs was "for free" :-)
> I'm not so sure (a year back I looked at the code with that in mind),
> and wonder if any quick hack would end up being opportunity lost.
>
> PCC, as a "classic" C compiler, only generates debug information at
> -O0.  This this is because the stabs code is restricted to the
> un-optimized code generator path.  Having the backend restricted to
> DWARF when '-O0' might just be ok, were it not for SSA (static single
> assignment).
I beg to differ.
- There is no requirement to not use optimizations when debugging, and 
has not been so in recent years.
- Why should it be any correlation to the debug format when using SSA 
representation or not?
> Just the SSA side of things (if debugging is ignored) is a lot of work
> (LLVM's solution was to largely ignore debugging.  I once asked
> Lattner directly about this and he answered that he considered it a
> "back-end problem").
I must admit that I do not understand what would be the problem here.
The SSA conversion (usually) only converts and moves stuff, which will
not affect the debug info more than marginally.

-- Ragge