Revert "HHVM calling conventions."

[Amir]

Summary

This reverts commit cce239c45d6ef3865a017b5b3f935964e0348734.

HHVM calling conventions are unused. Remove them by partially reverting the commit.

[Amir]

Addressed CodeGen/X86/statepoint-fastregalloc.mir test failure

[Amir]

Rebase

[MatzeB]

Makes sense to me to drop this and I like the simplification.

There is a chance that an out-of-tree target is overriding the getStackAlignmentSkew callback, but given that is at least pretty unlikely it's probably good to try to remove first and possibly bringing it back if there really was a user...

Added one nitpick but otherwise seems good to go.

llvm/include/llvm/IR/CallingConv.h

161–164

Maybe rename to make it more explicit this is gone now?

[MatzeB]

llvm/test/CodeGen/X86/statepoint-fastregalloc.mir

24

I guess this comment needs to be adapted or removed?

[Amir]

Rename CallingConv enum items

[Amir]

llvm/test/CodeGen/X86/statepoint-fastregalloc.mir

24

If I only replace the register name, would it still make sense? I'm removing csr_64_hhvm and apparently it has an effect on statepoint operands.

[maksfb]

For all I know, HHVM is not using it. Looks good on my end. Thanks.

[Amir]

Rename the register in statepoint-fastregalloc.mir test

[MatzeB]

llvm/test/CodeGen/X86/statepoint-fastregalloc.mir

24

This feels like they just choose the HHVM convention to show the concept. This feels like they just choose it because HHVM convention only had a single callee-saved register to choose from to make the test more stable. But at a first glance feels fine to switch to any other callee saved reg of the default calling convention instead...
You should subscribe the original author(s) of the test to this diff in case they have a comment.

[Amir]

llvm/test/CodeGen/X86/statepoint-fastregalloc.mir

24

Thanks!

@dantrushin – does this change look good to you?

[MatzeB]

LGTM

[MatzeB]

Please note build failures in the CI and fix before landing.

[Amir]

Rename calling convention enum members elsewhere

[Amir]

Update mlir LLVMEnums

[dantrushin]

llvm/test/CodeGen/X86/statepoint-fastregalloc.mir

24

Could you please replace csr_hhvm with csr_64_cxx_tls_darwin_pe instead? And register will change to $rbp.

[Amir]

Update test