[tree-ssa] Fix gcc.dg/tree-ssa/20030530-2.c

[Jason Merrill]

On 11 Jun 2003 10:24:45 -0400, Diego Novillo <dnovillo@redhat.com> wrote:

> On Wed, 2003-06-11 at 10:12, law@redhat.com wrote:
>
>> Doing these things exposes a latent but in how we set may_optimize_p for
>> expresssions.  Namely we set it for expressions in which TREE_SIDE_EFFECTS
>> is set.  tsk tsk.

> I thought that TREE_SIDE_EFFECTS should not be set on GIMPLE
> expressions, with the exception of CALL_EXPRs.

Don't forget volatile.

> Aren't you just papering over a gimplification bug here?

He fixed that bug, too.  :)

> Also, don't we recognize functions whose calls can be elided if they're
> called with the same arguments repeatedly?  (I forget the technical term
> :)

"pure".  Not yet, because of TREE_SIDE_EFFECTS.  Perhaps we shouldn't set
TREE_SIDE_EFFECTS on calls to pure functions.

Jason