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Subject: Re: [RFC] Contributing tree-ssa to mainline
From: Diego Novillo <dnovillo@redhat.com>
To: Geert Bosch <bosch@gnat.com>
Cc: Jan Hubicka <hubicka@ucw.cz>, "gcc@gcc.gnu.org" <gcc@gcc.gnu.org>,
   Richard Kenner <kenner@vlsi1.ultra.nyu.edu>
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On Mon, 2004-01-19 at 12:42, Geert Bosch wrote:

> There are many cases where we need to expand the original code in order
> to generate checks. Some Ada constructs generate a non-trivial amount of
> code, with calls to the Ada run time library, exception handlers etc.
> Once we expand such code, it is unlikely it could be optimized away.
> I agree with Richard that we need optimize away such constructs as early
> as possible, which is in the front end before expansion.
> 
Instead of emitting runtime calls, would it be possible to emit tree
codes with well defined semantics?  On finding them, the optimizers
would know that it's not just an arbitrary function call for instance
(perhaps adding attributes to the libcall).

But I'm oversimplifying.  We would have to talk about specific cases.


Diego.