[clang] [llvm] [OpenMP] OpenMP 5.1 "assume" directive parsing support (PR #92731)

[Alexey Bataev via llvm-commits]

alexey-bataev wrote:

> > > > don't you need more code in AST?
> > > 
> > > 
> > > Sorry, I don't quite understand the question! Could you elaborate a little please?
> > 
> > 
> > I was thinking maybe you need changes in AST related files, like `ASTWriter.cpp`, but that might be not needed as this is adding a new directive.
> 
> At the moment, since the "assume" directive is parsed but then immediately discarded, I don't think anything else is needed.
> 
> Actually the existing "assumes" support is reused -- the bit in SemaOpenMP.cpp adds the "assume" assumptions to the OMPAssumeScoped "stack". For "assumes", it's done like that so (e.g. top-level) declarations between begin/end "assumes" can be modified according to the assumptions on that stack. For "assume", once some use is made for the assumptions, that might turn out to not be the most useful representation. That can be revisited later though, I think.



> > > > don't you need more code in AST?
> > > 
> > > 
> > > Sorry, I don't quite understand the question! Could you elaborate a little please?
> > 
> > 
> > I was thinking maybe you need changes in AST related files, like `ASTWriter.cpp`, but that might be not needed as this is adding a new directive.
> 
> At the moment, since the "assume" directive is parsed but then immediately discarded, I don't think anything else is needed.
> 
> Actually the existing "assumes" support is reused -- the bit in SemaOpenMP.cpp adds the "assume" assumptions to the OMPAssumeScoped "stack". For "assumes", it's done like that so (e.g. top-level) declarations between begin/end "assumes" can be modified according to the assumptions on that stack. For "assume", once some use is made for the assumptions, that might turn out to not be the most useful representation. That can be revisited later though, I think.

Even so, it should support serialization/deserialization and have the tests for it (like ast-dump and ast-print).

https://github.com/llvm/llvm-project/pull/92731