Displaying 3 results from an estimated 3 matches for "super_rc".
2013 May 31
2
[LLVMdev] Register coalescer and reg_sequence (virtual super-regs)
...such for register coalescing decisions
(CoalescerPair::Partial = 0).
For example, I have a super reg that has r20, r21, r22, and r23 physical
registers. This super reg is the dest of a reg_sequence which generates 4
COPY MIs. The first COPY coalesces (merging into r20), but the vregs for
r21-r23 (SUPER_RC:%vreg50:subreg1..subreg3) are never coalesced after that
because doing so generates inteference on %vreg50, the "parent" super reg.
Is there a way to work around this? It causes unnecessary copies.
Thanks,
Joe
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2013 May 31
0
[LLVMdev] Register coalescer and reg_sequence (virtual super-regs)
...register coalescing decisions (CoalescerPair::Partial = 0).
>
> For example, I have a super reg that has r20, r21, r22, and r23 physical registers. This super reg is the dest of a reg_sequence which generates 4 COPY MIs. The first COPY coalesces (merging into r20), but the vregs for r21-r23 (SUPER_RC:%vreg50:subreg1..subreg3) are never coalesced after that because doing so generates inteference on %vreg50, the "parent" super reg.
>
> Is there a way to work around this? It causes unnecessary copies.
Is this happening on trunk, or are you using an old version of LLVM?
/jakob
2013 May 31
2
[LLVMdev] Register coalescer and reg_sequence (virtual super-regs)
...> (CoalescerPair::Partial = 0).
> >
> > For example, I have a super reg that has r20, r21, r22, and r23 physical
> registers. This super reg is the dest of a reg_sequence which generates 4
> COPY MIs. The first COPY coalesces (merging into r20), but the vregs for
> r21-r23 (SUPER_RC:%vreg50:subreg1..subreg3) are never coalesced after that
> because doing so generates inteference on %vreg50, the "parent" super reg.
> >
> > Is there a way to work around this? It causes unnecessary copies.
>
> Is this happening on trunk, or are you using an old vers...