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Re: SSA-based dead-code elimination
On Wed, Aug 02, 2000 at 11:31:48PM +0200, Laurent Guerby wrote:
> Mark Mitchell wrote [about empty loops removal]:
> > So, I think we should reserve your patch for the day when we actually
> > turn this stuff on by default.
>
> Will there be a documented way to generate an empty loop that survives
> optimization then? I can think of using a volatile variable, but this
> generates unecessary memory accesses.
One such way would be to us an empty asm (which given it doesn't specify target
and input arguments, should be treated as volatile):
int i;
for (i = 0; i < n; i++)
__asm__ ("");
--
Michael Meissner, Red Hat, Inc.
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