This patch removes the concept of a `function_type`-named type attribute
as a requirement for implementors of FunctionOpInterface. Instead, this
type should be provided through two interface methods, `getFunctionType`
and `setFunctionTypeAttr` (*Attr because functions may use different
concrete function types), which should be automatically implemented by
ODS for ops that define a `$function_type` attribute.
This also allows FunctionOpInterface to materialize function types if
they don't carry them in an attribute, for example.
Importantly, all the function "helper" still accept an attribute name to
use in parsing and printing functions, for example.
Reviewed By: rriddle, lattner
Differential Revision: https://reviews.llvm.org/D139447
* Split ops into X_graph variants as discussed;
* Remove tokens from non-Graph region variants and rely on side-effect
modelling there while removing side-effect modelling from Graph
variants and relying on explicit ordering there;
* Make tokens required to be produced by Graph variants - but kept
explicit token type specification given previous discussion on this
potentially being configurable in future;
This results in duplicating some code. I considered adding helper
functions but decided against adding an abstraction there early given
size of duplication and creating accidental coupling.
Differential Revision: https://reviews.llvm.org/D127813
The approach I took was to define a dialect 'extern' attribute that a GlobalOp can take as a value to signify external linkage. I think this approach should compose well and should also work with wherever the OpaqueElements work goes in the future (since that is just another kind of attribute). I special cased the GlobalOp parser/printer for this case because it is significantly easier on the eyes.
In the discussion, Jeff Niu had proposed an alternative syntax for GlobalOp that I ended up not taking. I did try to implement it but a) I don't think it made anything easier to read in the common case, and b) it made the parsing/printing logic a lot more complicated (I think I would need a completely custom parser/printer to do it well). Please have a look at the common cases where the global type and initial value type match: I don't think how I have it is too bad. The less common cases seem ok to me.
I chose to only implement the direct, constant load op since that is non side effecting and there was still discussion pending on that.
Differential Revision: https://reviews.llvm.org/D124318
