Non-const params use references and so need somewhere to store the
arguments. Local variables could be passed directly (parameters normally
require function storage class, which local variables are), but that's a
potential optimization for later.
This required adding a `var` symbol type. For now, it holds just the
storage class, but it might be good for the initializer, too.
Also, clean up some pointer/reference inconsistencies.
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.
It turns out my field access processing works well enough for vectors.
I'm not sure about pointer access as I may have done the pointer
dereference prematurely.
This gets parameter qualifiers to the parameters and thus `const`
parameters work as expected (even passes validation). However,
in/out/inout do not work yet due to incorrect setup of the function
call: spir-v wants them to be passed by reference (pointers) rather than
by value.
The function parameter and argument types are a mess with respect to
references (and thus calls don't pass validation) but the generated code
seems to be otherwise correct.
It wasn't quite as nasty as I thought, but splitting it up helps add a
little self documentation and, possibly more importantly, simplify
navigation through the type checks and argument setup.
I've long felt build_function_call was getting a bit big, and expr.c
especially so. This should make it easier to rewrite build_function_call
for dealing with target-specific code. As a bonus, the int through ...
warning is already cleaned up.
spir-v uses SSA, so temps cannot be assigned to directly, so instead use
the temp expression as a reference for the result id of the rhs of the
assignment. This would get function calls working if the they actually
emitted any code (right now, just a place-holder id so spirv-dis doesn't
fall over).
Also, fix some missing docs. Unfortunately, there are still some
problems (incorrect resolution for multiple files/functions with the
same name, and a bug with doxygen's verbatim/code blocks).
Unfortunately, the function isn't used yet, so it's easy to miss. I just
happened to notice things didn't look right when looking at my
projection matrices.
Ruamoko and v6(p) have their own copies despite being (currently) the
same, and spir-v's is currently empty, but now targeting spir-v doesn't
try to emit ruamoko code.
While a reference var can't be initialized yet, using them seems to work
in that they get dereferenced when the value needs to be read or written
(though I haven't seen any generated code for them yet).
It turns out my test was backwards: it fed the json text into a string
object then pulled it out, which of course round-tripped correctly. Now
things do round-trip correctly, but I had to ignore white-space
differences and edit the numbers as text->double->text doesn't
necessarily round-trip well (though double->text->double does with 17
digits).
I don't know why the last argument was handled differently. I suspect it
was a hold-over from before I added list handling. Removing it seems to
have made no significant difference (all tests pass still).
They're not actually used yet because all the calculations are giving me
a headache, but the improved handling of text direction in
Text_PassageView, along with passing the information, is important
enough, I think.
When the parameter is a reference, implicit casting is not allowed, but
when the parameter is by value and the argument is a reference, the
argument is dereferenced and promotion is allowed.
However, this covers only the selection of generic functions. It doesn't
deal with otherwise overloaded functions, nor does it do the actual
dereferencing or address taking.
Before adding references, looking at just type.type was ok whether or
not the type was an alias, but checking the deref flag needs the type to
be basic and not alias.
Simple functions now get to the code-gen phase (where they fail since
it's the wrong for other reasons). Parameter types aren't right for
spir-v yet as non-const params need to be references.
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.
