The main goal was to make it possible to give generic functions
definitions (since the code would be very dependent on the actual
parameter types), but will also allow for inline functions. It also
helped move a lot of the back-end dependent code out of semantics
processing and almost completely (if not completely) out of the parser.
Possibly more importantly, it gets the dags flushing out of the parser,
which means such is now shared by all front-ends.
There's probably a lot of dead code in expr.c now, but that can be taken
care of another time.
Arrays done via the field code since they use the same opcode and logic.
For now swizzles are just swizzles and don't support zeroing or negating
(but doing one or the other (not both) should be easy).
While storing the scope in a block was the right idea, the
implementation wasn't quite right as it resulted in the current scope
getting set at the wrong times resulting in incorrect symbol access when
shadowing was in effect.
I guess that was a mental FIXME for later, but later came sooner. The
declaration doesn't seem to be working properly, but I'll worry about
that later when I can get some automated tests going.
As I suspected, the dereference was premature, although it can act as an
optimization when multiple fields of an object are accessed, though it
won't work for writes to lvalues (which means my fixes for spir-v
code-gen currently don't work for lvalue writes). Still, progress. Need
to get field member ids set.
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.
I plan to do this eventually for Ruamoko, but I need it to keep working
for now; it's rather nice having multiple languages. I expect this will
open up a lot of options for inlining, generic/template function
instantiation, etc. Right now, it's helping with specialization
constants in glsl.
