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Re: Conditional call instruction




--On Wednesday, February 13, 2002 04:38:11 PM +0000 Richard Earnshaw 
<rearnsha@arm.com> wrote:

>> Do any of GCC's currently supported targets have a predicated call
>> instruction that GCC will use when appropriate?  Roughly speaking,
>> this is an instruction that calls only if some condition is true,
>> and otherwise falls through.
>
> Yes, the ARM has, but with the exception of the obsolete apcs-26 mode
> (only useful for very early ARM chips) the call will smash the
> condition-code register.  So a predicated call can only be used when it
> is  known that the condition code register won't be live afterwards.

But is sounds like, from Philip's mail, that GCC isn't smart enough
to use this feature.  Is that corret?

-- 
Mark Mitchell                mark@codesourcery.com
CodeSourcery, LLC            http://www.codesourcery.com


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