CC0 to CCmode conversion
James E Wilson
wilson@specifixinc.com
Tue Mar 22 22:16:00 GMT 2005
Denis Chertykov wrote:
> I think that sequence of compare + cond-jump will exists in any
> compiler pass.
Combine can optimize away compares, if you have other instructions that
set the condition code register to useful values. This optimization
will only work correctly if instructions that set or clobber the cc are
properly marked.
If no instructions are marked as setting the cc (other than compares),
then this will probably work, but you won't get any optimization from
combine, and may get worse code than before.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com
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