I'm developing a back end for a research SIMD processor.
I get the following error:
<<Remaining virtual register operands
UNREACHABLE executed at /llvm/lib/CodeGen/MachineRegisterInfo.cpp:144!>>
(when running with llc -O0, at end? of pass: "FAST REGISTER ALLOCATION")
Note that I used the suggestion from http://lists.llvm.org/pipermail/llvm-dev/2014-October/077632.html to "override requiresRegisterScavenging() and requiresFrameIndexScavenging() in your XXXRegisterInfo class to return true". However, this did not help.
A few more details: I create in a pass immediately after the first instruction scheduling phase a physical register (R31, a vector register), which I also reserve in [Target]RegisterInfo::getReservedRegs().
I also use instruction bundles.
Could somebody please help me with this problem?
Thank you very much,