Summary:
Update `OIGenerator` and out BUCK stuff for compile time OIL with OIL v2. Main things:
- Switch `OIGenerator` from the `getObjectSize` call to the new `introspect` call.
- Switch from looking at template parameters to looking at function parameters, as this was exposing a bug in our elfutils/drgn and this way it's the same as OID.
- Migrate `OIGenerator` to CodeGen v2 and update CodeGen v2 to accept a linkage name.
- Update the compile time example to be the same as the JIT example, using the new interface and the JSON exporter.
- Clean up the `ObjectIntrospection.h` header.
Differential Revision: D48687728
fbshipit-source-id: 2c3c041fd1b6499c5e02eb5e2082a977bfa529d7
Types within containers were previously named TODO. This sorts it out so
they're named as their most resolved type. The current implementation
skips Typedef names.
The TypeGraph class should only be responsible for storing Type nodes.
Traversing the graph and tracking which nodes have been visited should
not be included there.
Passes now take a NodeTrackerHolder as an input parameter, which
provides access to a zeroed-out NodeTracker.
Type Graph deduplicates and modifies names to better fit the generated
code, for example `int32_t[4]` becomes `OIArray<int32_t, 4>` and `struct
MyStruct` might become `struct MyStruct_0`.
Add an `inputName` which better represents the original input code which
can be used when building the tree.
This removes Printer's legacy behaviour of generating an ID for each
node as it gets printed. This old method meant that if new nodes were
added to or removed from a graph, every ID after the new/removed node
would change.
Now IDs are stable so it is easier to follow specific nodes through
multiple transformation passes in CodeGen.
Names which were generated on-demand are now stored in member variables,
which are set during the ctor and can be regenerated when required (by
NameGen).
We previously only marked as packed if there was no tail padding, which
was not a sufficient condition.
The new AlignmentCalcTest.PackedMembers test case is an example which
would previously not have been marked as packed.
