[llvm-commits] [PATCH] Scavenging callee-saved registers

[Chris Lattner]

On Aug 2, 2009, at 1:00 PM, Evan Cheng wrote:

>>
>> I noticed that ARM tries to predict this situation so an extra CSR
>> can be spilled. That probably means that ARM will never meet this
>> situation. Unless it guesses wrong for some reason. Blackfin is not
>> so advanced yet. It cannot predict scavenger use.
>
> Looks good. Please commit.
>
> I have a plan to completely revamp the use of register scavenger.
> Basically I want PEI to introduce virtual registers instead of
> scavenging. At the end of PEI it will do another round register
> allocation using the scavenger.

... with the constraint that the new vregs have are defined by one  
instruction and killed by the next, right?

-Chris