[LLVMdev] alias information on machine instructions

Florian Brandner fbrandne at mail.tuwien.ac.at
Thu May 24 00:09:56 PDT 2007

Dan Gohman wrote:
> On Wed, May 23, 2007 at 12:23:38AM -0700, Chris Lattner wrote:
>> On Fri, 4 May 2007, Florian Brandner wrote:
>>> i had a look at the SelectionDAG based schedulers. it seems that
>>> aliasing loads/stores are chained together by the DAGCombiner. after
>>> scheduling, when the MachineInstrs are created, the alias information
>>> cannot be used anymore in the current framework. is this correct?
>> Right.  The original Value*'s are preserved in the DAG, but dropped when 
>> MachineInstrs are created.  We could add a machineoperand to capture this 
>> Value* if desired.
> Another benefit of keeping the original Value*'s (and offsets) around is it
> would provide more information that could be used for verbose asm output
> and MachineInstr-level dumps, which would be quite nice.

i'll do this and post a patch, unless someone else is already working on


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