Now declarations can be deferred too, thus things like generic/template
and inline functions should be possible. However, the most important
thing is this is a step towards a cleaner middle layer for compilation,
separating front-end language from back-end code-gen.
And they even pass validation (though it turns out there's a bug in
glslangValidator regarding specialization constants with expressions (or
possibly spirv-val, but it seems to be the former as my bug report shows
signs of activity in that direction)).
https://github.com/KhronosGroup/glslang/issues/3748
They're currently wrong since they're meant to be for specialization
constants (and that whole system is currently broken anyway) but are
instead raw code expressions, but progress is progress.
The imports need their result id recorded somewhere (and the hard-coding
in qc-parse.y removed), but that's a little bit of progress getting
spir-v working.
While I'm not happy with the module "creation" (at least it's limited to
two places), setting it up with spir-v capabilities and memory model
seems quite nice and should play nicely with being set up from within
source code, though using uint constant expressions might be overkill.
A few more types and function parameters are set up more or less
correctly (however, the pointer storage class is hard-coded for now:
need to add attributes to everything).
