Re: Patch to add fake edges from calls to exit

[Toon Moene <toon at moene dot indiv dot nluug dot nl>]

Richard Henderson wrote:

> On Wed, Jan 10, 2001 at 09:15:59PM +0100, Toon Moene wrote:

> > I've contemplated in the past that it might be possible to also treat
> > specially the calls to routines guaranteed *not* to return...
> 
> We already do this.  That's what the "volatile" field
> in com-rt.def does.

Ah, yes - the Fortran Frontend *encodes* this - but what happens with
that information ?  In what sense are __noreturn__ function treated
specially ?

One of the things you *can* do with __noreturn__ functions is to reorder
the code such that only one call site is generated and every call is
converted to jumps to that call site, after which a lot of
"jump-to-jumps" can be eliminated.

[ Hmmm, using a small test program, I see that something like that
  already happens ... ]

-- 
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