[LLVMdev] [global-isel] Proposal for a global instruction selector

[dag at cray.com]

Jakob Stoklund Olesen <stoklund at 2pi.dk> writes:

>> So the question is if the plan is to make MI a "complete" IR, that we
>> can serialize independently of the LLVM IR, run a single pass on, etc.
>
> Absolutely, although that project is somewhat orthogonal to the design
> of the instruction selector.
>
> Some back-references are pointers into IR functions, such as MBB
> holding a pointer to its BasicBlock and MachineMemOperand referencing
> a pointer Value. These references should definitely be cleaned up.

I agree a cleanup here would be great.

How would we handle machine-level alias analysis without pointer types?
MachineMemOperands and their Ptr members currently provide information
that can be used by alias analysis at the MI level.  We use that quite a
bit here.

Overall I really like the direction this is heading.  Thanks for
spearheading this, Jakob!

                           -David