Most I/O registers are already described by the shader signatures.
The registers that are not do not have any property other then
being used by the program or not, so they can be collectively
described with a bitmap.
The register storage class is now represented in
vkd3d_register_builtins, so the spirv_compiler_emit_io_register()
doesn't need to know it from the caller.
Instead of returning nonsense (such as, currently, a type with zero size).
In practice this improves error reporting for shaders such as the following:
void func(float x[])
{
float y[] = {x};
}
Currently this outputs a nonsense
test.hlsl:1:19: E5002: Implicit size arrays not allowed in function parameters.
test.hlsl:3:7: E5002: Implicit size arrays need to be initialized.
With this patch the second warning is removed.
Instead of using DCL_INPUT.
The main goal here is to eventually get rid of the I/O
declaration instructions. A positive side effect is that we don't
add a useless barrier to shaders which have a DCL_INPUT instruction
in the patch constant phase but don't actually read OUTCONTROLPOINT
registers.
This makes it available to all backends, without requiring an
ad-hoc solution for each of them. It also gets rid of an
undocumented flag we're currently passing to
DCL_CONTROL_POINT_PHASE.
