[PATCH] D16239: Fix PR25526 by adding back limited cmpxchg pseudo-Insts

[Ahmed Bougacha via llvm-commits]

ab added a comment.

There's still the live-in issue, but I'm not sure anyone cares after pseudo expansion. Quentin tells me you can use LivePhysRegs (::stepBackwards) to compute that for you.

Also, it occurs to me that nothing prevents a spill from being inserted with optimized regalloc.  It's probably extremely unlikely, but maybe we should consider using the pseudo regardless of the opt level..


http://reviews.llvm.org/D16239