First part of v2 of !27, which aims to:
* Allow allocation of variables of complex types that contain both numerics and objects across multiple register sets (regsets). * Support the tex2D and tex3D intrinsics, inferring generic samplers dimension from usage, writing sampler declarations, and writing sample instructions. * Support for arrays of resources for both SM1 and SM4 (not to be confused with the resource-arrays of SM 5.1, which can have non-constant indexes). * Support for resources declared within structs. * Support for synthetic combined samplers for SM1 and synthetic separated samplers for SM4, considering that they can be arrays or members of structs. * Imitate the way the native compiler assigns the register indexes of the resources on allocation, which proved to be the most difficult thing. * Support for object components within complex input parameters. * Small fixes to corner cases.
This part consists on parsing the `tex2D()` and `tex3D()` intrinsics and beginning to support the allocation of variables across multiple regsets.
The whole series, is on my [master6](https://gitlab.winehq.org/fcasas/vkd3d/-/commits/master6) branch.