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Re: PR19578: noreturn vs. function pointer propagation part 2


On Wed, 2005-01-26 at 22:28 +0000, Richard Sandiford wrote:
> Diego Novillo <dnovillo@redhat.com> writes:
> > When building the flowgraph, consider indirect calls block
> > terminators.  It's probably the easiest approach, but it may have a
> > negative impact on some codes with many indirect calls (see
> > stmt_ends_bb_p).
> 
> OK, the patch below does that... kind of.  It actually changes
> is_ctrl_altering_stmt (the predicate used by stmt_ends_bb_p)
> so that indirect calls are conservatively treated as being
> control-altering.
> 
> Bootstrapped & regression tested on i686-pc-linux-gnu.  OK to install?
> 
> Richard
> 
> 
> 	PR tree-optimization/19578
> 	* tree-cfg.c (is_ctrl_altering_stmt): Return true for indirect calls.
I had to sit down and think about this for a while -- I was somewhat
worried that it might pessimize code.  However, I think that concern is
unwarranted given this effects just the tree optimizers, which are not
nearly as pessimistic at block boundaries as their RTL cousins.

Approved.

jeff



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