I decided to not mess with actual casts. In retrospect, this is probably
for the best as it avoids any bit-cast conflicts, but should allow for
block initializers with a few tweaks. `@construct (type, args...)` in
Ruamoko follows the same path as `type(args...)` in glsl.
Because the symbol tables for generic functions are ephemeral (as such),
they need to be easily removed from the scope chain, it's easiest if
definitions are never added to them (instead, they get added to the
parent symbol table). This keeps handling of function declarations or
definitions and their parameter scopes simple as the function gets put
in the global scope still, and the parameter scope simply gets
reconnected to the global scope (really, the generic scope's parent)
when the parameter scope is popped within a generic scope.
The back-end support for renamed builtins (fte's = #0:name) was needed
for pascal functions because the internal name is now prefixed with an @
to allow the lvalue/rvalue selection of behavior for function symbols
Because the glsl front-end uses Ruamoko to compile its builtins, it
needs to switch languages, and the cleanest way to do so is to use a
context object that gets passed around. This removes not only the
current_language global, but also (as a bonus) any real references to
flex's scanner object (there's still a pointer in rua_ctx_t, but it's no
longer a parameter (which caused some pain in the change)).
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.
I guess I'd wanted to avoid supporting automatic types in type
functions, but that broke long and unsigned int: either no type, or just
int, depending on the decl style.
I'm not sure what it's useful for, but GLSL has a function for it thus I
decided to add the instruction to the VM, so this is part of the
compiler side.
Explicitly typed compound initializers are what C uses and allows them
to initialized `auto` vars and even pass through `...`. Not tested yet
other than ensuring existing tests didn't break.
Since spir-v needs actual bools for its conditional instructions, the
time to do bool properly finally came. As expected, the changes caused
quite a mess, but Ruamoko now does bool/true/false.
I realized that spir-v pointers are essentially references (the way
they're used) since OpVariable requires a pointer type rather than the
base type. Thus, under the hood, references are just pointers with
automatic dereferencing. However, nothing uses references yet, and I
expect to run into issues with is_pointer vs is_reference vs is_ptr
(high-level pointer, reference, low-level pointer, respectively).
Since begin_function creates the parameter and locals scopes, there's no
need for another scope for the function body. This fixes the detection
of shadowed parameters for Ruamoko and QuakeC.
I don't remember why I thought it was a good idea at the time, but I
decided that having the union was a bit iffy and making the list
"official" would be a good idea. In the end, it removed a nice chunk of
code (redundant list manipulations).
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.
I don't know why I thought it was a good idea to make sy_var context
dependent. Renaming sy_var to sy_def makes it a little easier to know to
use the def field, too.
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.
Its grammatical usage is such that it's unambiguous with identifiers,
and is needed for parsing the glsl functions (the not() function for
boolean vectors).
This is needed for `unsigned int` or `unsigned long` in type
expressions. However, there is a problem where @vector etc complain
about just `unsigned` (which should default to int, of course).
Now parameters can be declared `const`, `@in`, `@out`, `@inout`. `@in`
is redundant as it's the default, but I guess it's nice for
self-documenting code. `const` marks the parameter as read-only in the
function, `@out` and `@inout` allow the parameter to pass the value back
out (by copy), but `@out` does not initialize the parameter before
calling and returning without setting an `@out` parameter is an error
(but unfortunately, currently detected only when optimizing).
Unfortunately, it seems to have broken (only!) v6 progs when optimizing
as the second parameter gets optimized out.
The code for it and make_param were nearly identical, but it turned out
that just setting up the symbol correctly was all that was needed before
passing the spec to make_param. This will make implementing parameter
qualifiers easier (less repetition).
Other than contructors (and problems with the `out` block) qfcc can
compile fstrianglest.vert to what looks like working ruamoko code.
There's still a lot of work to do, though.
Using a struct with function pointers instead of switching on an enum
makes it much easier to add languages and, more importantly,
sub-languages like glsl's shader stage variants.
I don't know why I didn't apply the same ideas as in methoddef, maybe I
just forgot. I'm pretty sure I did methodproto first, or maybe cleaned
up methoddef much later then didn't think of methodproto. Still, the
grammar is much nicer to read now.
Arrays of functions or functions that return arrays or functions aren't
valid. While working on how to get generics in properly, I finally
understood what's going on with function types in the specifier, and I
think I'll be able to sort out function pointers vs prototypes, too.
Generic qc-style prototypes don't work but both c and qc style
definitions get as far as trying to build the builtin function. It
starting to look like I need to rework function handling, which isn't
all that surprising as it hasn't changed much over 22 years.
Most of them were noise from the type const correctness pass, but the
qc field function handling was always dubious (though in practice safe
due to how the type was built, but...). The remaining casts outside of
type.c need some thought.
That is, `@generic(...) { ... };`, which is handy for bulk declarations
(such as for glsl). This proved to be a lot harder than expected, I
suspect handling of specifiers needs a lot of work.
I never did like all those cryptic parameters, especially when they were
just 0 and 1. Now the individual specifier creation functions take only
those parameters they need (if any) and there's no possibility of
conflicting parameters. Also, it's clearer what the new specifier does.
This fits in nicely with the rest of the generic type system and makes
it a little more useful. The idea is it will take a return type (already
does since type functions always require a parameter at this stage) and
a parameter list (not implemented yet). It currently resolves to the
basic void (...) function type for QC.
It turns out they're not needed as the difficulty of quakec function
declarations (function fields) is taken care of by qc_function_spec.
Also, they made it difficult to think about function declarations.
