Split MachineBasicBlocks

Hi all,

as soon as I try to split MachineBasicBlocks the resulting programs suffer
from segmentation faults.

I have reproduced the error using a simple MachineFunctionPass in the X86
backend that splits MachineBasicBlocks before CALL32m instructions (and
inserts a fallthrough-jmp). The MachineFunctionPass is plugged into
X86TargetMachine::addPreRegAlloc. The split-method is basically stolen from
BranchFolder::SplitMBBAt.

Currently I use the gcc benchmark from SPEC2000 to generate the error, but I
guess every reasonably complex program will do. I have attached my
MachineFunctionPass, in case you need to look at the code. Does anyone have
an idea what is wrong here?

- Artjom

http://www.nabble.com/file/p25552660/SplitMinPass.cpp SplitMinPass.cpp