[CIR] Add GEP flags to ptr stride op

[badumbatish]

From the comment on PR review #1844, it seems like we're missing the flags for GEP.

I'm opening the PR to add the flags.

The first commit is just a prototype to gather opinions and reviews to see if I'm heading to the right direction with this.

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[bcardosolopes]

Nice! This also needs CIRGen changes and lowering to LLVM support, but looks like a good start

[tommymcm]

It might make sense for cir.get_element to get the same treatment. Maybe we should have it inherit from ptr_stride to avoid duplicating everything? get_element is essentially just a ptr_stride with 'better' type information.

[badumbatish]

is there any historical reason why we didn't consolidate the two?

[tommymcm]

is there any historical reason why we didn't consolidate the two?

Nope, I introduced get_element recently-ish. It just didn't have any meaningful overlap until this. Other option is having them share a parent (some kind of "ptr_arith" base class).
This can all be handled in a later PR though.

[andykaylor]

I like get_element as a separate operation, because it does something logically different than ptr_stride, but if we can share code between them, we should.

[badumbatish]

I added lowering and codegen, I added OGCG test initially but was reluctant if i should push it.

I also didn't remove the missing feature check, i'm not sure how feature ready this is compared to OG.

[xlauko]

Can this be first ported to incubator then mirrored here.

[badumbatish]

Can this be first ported to incubator then mirrored here.

I dont quite follow, this repo is the incubator yes?

[tommymcm]

Need to update the CIR-to-LLVM GEP flag function. Also some formatting nits.

[xlauko]

Can this be first ported to incubator then mirrored here.

I dont quite follow, this repo is the incubator yes?

Yeah sorry, I was jumping in between PRs and missed that this was already in clangir.

[badumbatish]

i got an unrelated code formatting error, should I wait for the formatting PR to come in separately or do you guys want me to include the correct formatting as well?

[bcardosolopes]

i got an unrelated code formatting error, should I wait for the formatting PR to come in separately or do you guys want me to include the correct formatting as well?

How sure it's unrelated? Is it showing up in other PRs? I see at least clang/test/CIR/CodeGen/pointers.cpp in the list, haven't checked the others. If you can reproduce locally and there's a small workaround you could include that'd be welcome

[badumbatish]

clang-format CI shows this file not passing the CI but this PR doesn't include the lines in those files

[bcardosolopes]

Gotcha, maybe we made a mistake and landed non-formatted things, just landed a fix for it. Can you rebase the PR just to make sure it goes smooth?

[bcardosolopes]

LGTM, I'll merge as soon as it passes all tests