[LLVMdev] MachineMemOperands

[Chris Lattner]

On Dec 1, 2009, at 1:10 PM, David Greene wrote:

> On Tuesday 01 December 2009 15:04, Chris Lattner wrote:
> 
>>> The size is actually calculated from an EVT nearly everywhere (and
>>> where it's not it should be easy to add).  We could just replace the
>>> size with the EVT and have more information.
>> 
>> It sounds like you're looking for a property of an instruction, not an
>> operand.  If you're looking for vector instructions, that should be
>> captured in TargetInstrInfo, not in MachineInstrs/Operands.
> 
> Yes, I've written all that support.  But that doesn't cover 
> MachineMemOperands.  AFAIK there's no machine-independent way to tell which
> instruction operands make up a MachineMemOperand.  And even then, that would
> only tell you about the compoenents that make up the address, not the data
> itself.  Note that having a machine-independent way to associate 
> MachineOperands with MachineMemOperands would also be highly useful, but
> that will come later.

Again, you're saying that you need something without explaining what for. :)  We don't have a strong model for what is an 'operand' (memoperands are not bound to a particular list of MachineOperands).  If you want to fix that problem, the fix isn't to add an MVT to memoperands.

-Chris