SPV_EXT_shader_viewport_index_layer enables using ViewportIndex
and Layer in vertex and tessellation shaders.
Also, as per the Vulkan spec:
> The ViewportIndex decoration must be used only within vertex,
> tessellation evaluation, geometry, and fragment shaders.
> In a vertex, tessellation evaluation, or geometry shader, any
> variable decorated with ViewportIndex must be declared using
> the Output storage class.
> In a fragment shader, any variable decorated with ViewportIndex
> must be declared using the Input storage class.
Similarly for Layer.
* Reworked how execution model limitations are checked
* Now OpFunction checks which entry points call it and checks its
registered limitations instead of building a call stack in the entry
point
* New tests
* Moving function to entry point mapping into VState
Relaxs checks for per-vertex builtin variables. If the builtin
decoration is applied to a variable, then those checks now allow a level
of arraying on the variable before checking the type consistency.
* Allows arrays of variables to be present for the per-vertex variables:
* Position
* PointSize
* ClipDistance
* CullDistance
* Updated tests
According to Vulkan spec 1.1.72:
> The PrimitiveId decoration must be used only within fragment,
> tessellation control, tessellation evaluation, and geometry shaders.
> In a tessellation control or tessellation evaluation shader, any
> variable decorated with PrimitiveId must be declared using the Input
> storage class.
We were enforcing that PrimitiveId can only be used with Output
storage class for TCS and TES before.
At every definition of a builtin id, run at-reference-check rules on the
defining instruction as well.
Previosly the validation was missing the case when invalid storage class
was defined in the instruction which defines the built-in, and not in
the instruction which references the built-in.
Refactored validate built-ins to make
GetExecutionModels(entry_point)
and
GetExecutionModes(entry_point)
available in validation state.
Entry points are allowed to have multiple execution modes and execution
models.
Finished the last missing feature in Vulkan built-ins validation:
FragDepth requires DepthReplacing.
Added a framework for validation of BuiltIn variables. The framework
allows implementation of flexible abstract rules which are required for
built-ins as the information (decoration, definition, reference) is not
in one place, but is scattered all over the module.
Validation rules are implemented as a map
id -> list<functor(instrution)>
Ids which are dependent on built-in types or objects receive a task
list, such as "this id cannot be referenced from function which is
called from entry point with execution model X; propagate this rule
to your descendants in the global scope".
Also refactored test/val/val_fixtures.
All built-ins covered by tests
