Displaying 1 result from an estimated 1 matches for "readsundefsubreg".
2018 Apr 25
0
liveness tracking of a register class with a single sub-register
Hi list.
I'm trying to enable sub-register liveness tracking for our target but I'm hitting the following assert on VirtRegRewriter::readsUndefSubreg:
assert(SubRegIdx != 0 && LI.hasSubRanges());
The reason is that I have a register class of two bit predicates where only the low bit is allocatable so there's only a single sub-register.
Now, MachineRegisterInfo only enables sub-reg liveness tracking for a class if it has at least...