preferring consecutive registers in allocater

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1

Hi,
Im trying to give priority for some machine instruction to allocate consecutive registers,
I saw some Architectures like ARM is “forcing” some instructions to use consecutive registers but in my case I do not want to force but to “prefer”, so if it will create spills I wont choose consecutive registers…

any ideas how to do this?
I saw “getRegAllocationHints” function but didnt see how it will help…
seems that I need to create a new Register Allocator by inheriting the Base Register Allocator…

thanks,
Atheel

2

Hi Atheel,

With getRegAllocationHints you have access to the machine function and
the register you are assigning.
Using this information, you can take a look at the instructions that
uses the register being assigned and the surrounding area and
influence the allocation order based on that.

Cheers,
-Quentin