The job of this abstraction is to provide staging buffers for temporary
operations. Think of image uploads or buffer uploads to device memory.

It automatically deletes unused buffers.

The intention behind this hasheable structure is to describe the state
of fixed function pipeline state that gets compiled to a single graphics
pipeline state object. This is all dynamic state in OpenGL but Vulkan
wants it in an immutable state, even if hardware can edit it freely.

In this commit the structure is defined in an optimized state (it uses
booleans, has paddings and many data entries that can be packed to
single integers). This is intentional as an initial implementation that
is easier to debug, implement and review. It will be optimized in later
stages, or it might change if Vulkan gets more dynamic states.

Use a large flat array to look up texture formats. This allows us to
properly implement formats with different component types. It should
also be faster.

Enable sign conversion warnings but don't treat them as errors.

Add an intermediary class that implements common functions across GPU
accelerated rasterizers. This avoids code repetition on different
backends.

VideoCore: Unify const buffer accessing along engines and provide ConstBufferLocker class to shaders.

Implement VOTE using Nvidia's intrinsics. Documentation about these can
be found here
https://developer.nvidia.com/reading-between-threads-shader-intrinsics

Instead of using portable ARB instructions I opted to use Nvidia
intrinsics because these are the closest we have to how Tegra X1
hardware renders.

To stub VOTE on non-Nvidia drivers (including nouveau) this commit
simulates a GPU with a warp size of one, returning what is meaningful
for the instruction being emulated:

* anyThreadNV(value) -> value
* allThreadsNV(value) -> value
* allThreadsEqualNV(value) -> true

ballotARB, also known as "uint64_t(activeThreadsNV())", emits

VOTE.ANY Rd, PT, PT;

on nouveau's compiler. This doesn't match exactly to Nvidia's code

VOTE.ALL Rd, PT, PT;

Which is emulated with activeThreadsNV() by this commit. In theory this
shouldn't really matter since .ANY, .ALL and .EQ affect the predicates
(set to PT on those cases) and not the registers.

Implements a templated class with a similar approach to our current
generic texture cache. It is designed to be compatible with Vulkan and
OpenGL,

Analysis passes do not have a good reason to depend on shader_ir.h to
work on top of nodes. This splits node-related declarations to their own
file and leaves the IR in shader_ir.h

Instead of having a vector of unique_ptr stored in a vector and
returning star pointers to this, use shared_ptr. While changing
initialization code, move it to a separate file when possible.

This is a first step to allow code analysis and node generation beyond
the ShaderIR class.

sirit is a runtime assembler for SPIR-V

data_compression: Move LZ4 compression from video_core/gl_shader_disk_cache to common/data_compression

Implements an API agnostic texture view based texture cache. Classes
defined here are intended to be inherited by the API implementation and
used in API-specific code.

This implementation exposes protected virtual functions to be called
from the implementer.

Before executing any surface copies methods (defined in API-specific code)
it tries to detect if the overlapping surface is a superset and if it
is, it creates a view. Views are references of a subset of a surface, it
can be a superset view (the same as referencing the whole texture).
Current code manages 1D, 1D array, 2D, 2D array, cube maps and cube map
arrays with layer and mipmap level views. Texture 3D slices views are
not implemented.

If the view attempt fails, the fast path is invoked with the overlapping
textures (defined in the implementer). If that one fails (returning
nullptr) it will flush and reload the texture.