[PATCH] D35985: Skip live range segment verification for reserved physregs

[Stefan Maksimovic via Phabricator via llvm-commits]

smaksimovic added a comment.

Sorry for not getting back at this earlier.

I inquired for the live range information of the register unit belonging to the $f13 register at the beginning of RegisterCoalescer::runOnMachineFunction() and it turned out to be non-empty.
Checking for the same live range information in the Live Variable Analysis pass which directly precedes Simple Register Coalescing pass revealed that it is empty.
Since the passes are executed one after another I couldn't pinpoint where exactly the live range information is generated.

As a side note, we could remove the live range for the register unit in question at the end of RegisterCoalescer::joinReservedPhysReg() right before we delete the COPY machine instruction.
Would that solution be accceptable?


https://reviews.llvm.org/D35985