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Re: SSA-based dead-code elimination
>>>>> "Laurent" == Laurent Guerby <guerby@acm.org> writes:
Laurent> 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.
Laurent> Will there be a documented way to generate an empty loop
Laurent> that survives optimization then? I can think of using a
Laurent> volatile variable, but this generates unecessary memory
Laurent> accesses.
The usual use for such a thing is a timing loop on an embedded system.
In that case, you already need intimate knoweldge of the processor.
You can write the loop as a volatile asm, and the optimizer will leave
it alone.
--
Mark Mitchell mark@codesourcery.com
CodeSourcery, LLC http://www.codesourcery.com