Conditional call instruction
Mark Mitchell
mark@codesourcery.com
Wed Feb 13 08:44:00 GMT 2002
--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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