Support generic `struct` types during IR-based emit

Fixes #318

Most of the required support was actually in place, so this is just a bunch of fixes:

- Detect when we are in "full IR" mode, so that we can always emit `struct` declarations with their mangled named (which will produce different names for different specializations, since we emit decl-refs)

  - Carefully exclude builtin types from this for now. We'll need a more complete solution for mapping HLSL/Slang builtin types to their GLSL equivalents soon.

- Skip emitting types referenced by generic IR functions, since they might not be usable.

  - Also fix things up so that we emit types used in the initializer for any global variables.

- Fix bug in generic specialization where we specialize the same function more than once, with different type arguments. We were crashing on a `Dictionary::Add` call where the key already exists from a previous specialization attempt.

- Fix name-mangling logic so that when outputting a possibly-specialized generic it looks for the outer-most `GenericSubstitution` rather than just the first one in the list. This is to handle the way that we insert other substitutions willy-nilly in places where they realistically don't belong. :(

All of these changes together allow us to pass a slightly modified (more advanced) version of the test case posted to #318.

0 files changed, 0 insertions, 0 deletions