[LLVMdev] RFC: Machine Instruction Bundle

[Jakob Stoklund Olesen]

On Dec 5, 2011, at 1:50 PM, Jakob Stoklund Olesen wrote:

> I would like to use bundle DBG_VALUE instructions so we can avoid silly code like this:
> 
>  MachineBasicBlock::iterator InsertPos = mi;
>  while (InsertPos != MBB->begin() && llvm::prior(InsertPos)->isDebugValue())
>    --InsertPos;
>  MachineBasicBlock::iterator From = KillMI;
>  MachineBasicBlock::iterator To = llvm::next(From);
>  while (llvm::prior(From)->isDebugValue())
>    --From;

Thinking about it, this probably wouldn't work for pre-RA passes that can delete code. They could inadvertently delete DBG_VALUE instructions.

/jakob