And, nicely, simplify it quite a bit. I'm not sure why I didn't thinkg
of this approach before. While the ruamoko back-end doesn't support
matrices yet, the expressions are handled.
As a side effect, type checking on comparisons is "stricter" in that
more potentially bogus comparisons (eg, int-float) are caught, resulting
in a few warnings in ruamoko code and even finding a couple of bugs.
Using bit masks for valid source types for each destination type makes
the logic a lot easier to read. Still had to have some explicit checks
for enums and bools.
The code gen return statements checks for out/inout parameters in the
current function and thus could result in some undesired behavior when
constants are evaluated within such a function.
I found a need to check for shifts separately (not sure it's the right
approach for that problem, though), and there are a few more math ops
than just +-*/.
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.
The tricky bit was figuring out how to get `floor()` out of the
available instructions. It's handy that the comparison ops always
returned floats and didn't force the use of branches.
Now both width and columns must match for an instruction to be selected.
Found a few errors in my opcode specs, and some minor goofs in the type
system (really just overthinking things when I added matrices).
Implemented via specific overloads of the function.
It's not quite working correctly in that parameter names are taken from
the declaration instead of definition. However, this seems to be an old
bug that went unnoticed due to me almost always using the same parameter
names in declaration and definition.
Also, the code in get_function() is a horrible mess.
However, the basic idea turned out to be simpler than I though (though
details of the implementation are indeed a little trickier): generic
functions are essentially prototype generators when implemented using
non-generic specialized overloads.
Yet another step closer to glsl support.
While it wasn't correct anyway (neither vectors nor quaternions are
colors), the additional names broke q.s in the quaternion.r test, likely
due to there being two s fields.
For now, it's just recording that type type has attributes (encoding
begins with %) and resurrecting types_same which is used only when
matching with types with attributes, so there's still a fair bit of work
to do.
I'm not sure why I made those functions take const type_t *, but they
didn't need it. There's still a relevant fixime in find_handle, but I
haven't decided how to fix that one just yet.
I'm sure there are still some warts, but interface declaration now works
for spir-v and a real vertex shader can be compiled (albeit one that
doesn't use matrices).
