[LLVMdev] Determining the register type of a MachineOperand

David Greene dag at cray.com
Fri Sep 26 08:38:39 PDT 2008


On Wednesday 24 September 2008 15:23, Mon Ping Wang wrote:
> To my knowledge, I don't think there is an easy way to get the MVT
> information from a MachineOperand.   Why do you need it for?  In my

See the thread I started on this very topic.  Spilling is one place you'd like 
to have this information.

> mind, the MachineInstr and its associated operands represent a
> physical machine instruction and I typically want to think of those as
> machine opcodes and machine register files.  I am typically interested
> in the mapping of MVTs to register classes when I'm generating machine
> instructions.  Note that a register class may map to multiple MVTs
> depending on your description.

Right, but the instruction opcode should give a clue about what the bits 
represent.  That mapping is what's currently missing.

                                              -Dave



More information about the llvm-dev mailing list