[LLVMdev] LiveIntervals, replace register with representative register?

Chris Lattner sabre at nondot.org
Wed Sep 7 13:05:33 PDT 2005

On Thu, 8 Sep 2005, Tzu-Chien Chiu wrote:

> On 08/09/05, Alkis Evlogimenos <evlogimenos at gmail.com> wrote:
>> representative register (found using a union find algorithm). Note that
>> the representative register could be a real register if we ever joined
>> an interval of a real register with one of a virtual register (and this
>> real register will be the representative register of the set of
>> intervals joined together).
> I understand the representative register could be a physical (real)
> register if one of the coallescing register is a physical register.
> But the code _uncondtionally_ changes MachineOperand::optype to
> MO_MachineRegister, why?
> (Same question as my previous post)

See above.  There is no distinction, and some of these changes are 
required by the SparcV9 backend.  This kind of stuff will be cleaned up 
over time.



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