When running Civ6 using LLVM from git (SHA1's tested
1648ceaabcea762590049a74ce8b934e3bfd4fb2 and
897444660daf9e94c020efc97b63aed7e61db7ac) with R600_DEBUG=sisched and the
latest Mesa it would assert with the following error:

Civ6:
/var/tmp/portage/sys-devel/llvm-9999/work/llvm-9999/lib/Target/AMDGPU/SIMachineScheduler.cpp:1584:
void llvm::SIScheduleBlockScheduler::blockScheduled(llvm::SIScheduleBlock*):
Assertion `LiveRegsConsumers[RegP.first] == 0' failed.

This doesn't happen with LLVM-4.0.0-rc1 even when using R600_DEBUG=sisched