This is the last item of the OpenACC 3.3 spec. It includes the
implicit-name version of 'routine', plus significant refactorings to
make the two work together. The implicit name version is represented as
an attribute on the function call. This patch also implements the
clauses for the implicit-name version, as well as the A.3.4 warning.
These 4 clauses are mutually exclusive, AND require at least one of
them. Additionally, gang has some additional restrictions in that only
the 'dim' specifier is permitted. This patch implements all of this, and
ends up refactoring the handling of each of these clauses for
readabililty.
The 'routine' construct has two forms, one which takes the name of a
function that it applies to, and another where it implicitly figures it
out based on the next declaration. This patch implements the former with
the required restrictions on the name and the function-static-variables
as specified.
What has not been implemented is any clauses for this, any of the A.3.4
warnings, or the other form.
Currently we just emit a generic 'not implemented' diagnostic for all
OpenACC pragmas. This patch moves the diagnostic to 'Sema' and diagnoses
for a specific clause or construct, in preperation of implementing Sema
for constructs.
'bind' takes either a string literal, or an 'identifier' representing
the device-side function that this routine is intended to 'bind' to
(that is, to call). However, it seems that the intent is to permit the
'identifier' to reference any function, thus we're implementing this as
an ID expression.
Additionally, while working on this I discovered that the 'routine' ID
expression parsing for C++ wouldn't allow non-static member functions to
be referenced since it expected us to call it, this was fixed as a part
of this patch as the 'bind' support needed it too. A test was added for
routine.
The 'routine' construct applies either to a function directly, or, when
provided a name, applies to the function named (and is visible in the
current scope). This patch implements the parsing for this. The
identifier provided (or Id Expression) is required to be a valid,
declared identifier, though the semantic analysis portion of the Routine
directive will need to enforce it being a function/overload set.
