Displaying 2 results from an estimated 2 matches for "enablegprtovecspills".
2020 Sep 09
2
spill to register not stack?
...t; wrote:
>
> On PowerPC, we implemented support for spilling GPR registers to vector registers. Essentially, it requires specifying the correct register class in `getLargestLegalSuperClass()` as well as `storeRegToStackSlot()/loadRegFromStackSlot()`. You can see what is controlled with the `EnableGPRToVecSpills` option.
>
> If you also want to use this method for spilling callee-saved registers to other registers, you can do what we do on PPC in `assignCalleeSavedSpillSlots()` to specify the destination register. This should also ensure that the CFI directives are emitted correctly. Keep in mind th...
2020 Sep 09
2
spill to register not stack?
Given an architecture with two classes of registers: A is general purpose and
has an "adequate" number of registers, and C which is special purpose and has
very few (e.g. one) register. There are cheap instructions that directly copy
from C to A and vice versa.
If we need another C register and they are all live, we need to spill one.
Currently as far as I can tell, the only way to