HLSL allows type keywords to also be identifiers, so a sequence such as "float half = 3" is
valid, or more bizzarely, something like "float.float = int.uint + bool;"
There are places this is not supported. E.g, it's permitted for struct members, but not struct
names or functions. Also, vector or matrix types such as "float3" are not permitted as
identifiers.
This PR adds that support, as well as support for the "half" type. In production shaders,
this was seen with variables named "half". The PR attempts to support this without breaking
useful grammar errors such as "; expected" at the end of unterminated statements, so it errs
on that side at the possible expense of failing to accept valid constructs containing a type
keyword identifier. If others are discovered, they can be added.
Also, half is now accepted as a valid type, alongside the min*float types.
This PR adds a CreateParseContext() fn analogous to CreateBuiltInParseables(),
to create a language specific built in parser. (This code was present before
but not encapsualted in a fn). This can now be used to create a source language
specific parser for builtins.
Along with this, the code creating HLSL intrinsic prototypes can now produce
them in HLSL syntax, rather than GLSL syntax. This relaxes certain prior
restrictions at the parser level. Lower layers (e.g, SPIR-V) may still have
such restrictions, such as around Nx1 matrices: this code does not impact
that.
This PR also fleshes out matrix types for bools and ints, both of which were
partially in place before. This was easier than maintaining the restrictions
in the HLSL prototype generator to avoid creating protoypes with those types.
Many tests change because the result type from intrinsics moves from "global"
to "temp".
Several new tests are added for the new types.
These HLSL types are guaranteed to have at least the given number of bits, but may have more.
min{16,10}float is mapped to EbtFloat at medium precision -> SPIRV RelaxedPrecision
min{16,12}int and min16uint are mapped to mediump -> SPIR-V RelaxedPrecision
There's a lot to do for RWTexture and RWBuffer, so it will be broken up into
several PRs. This is #1.
This adds RWTexture and RWBuffer support, with the following limitations:
* Only 4 component formats supported
* No operator[] yet
Those will be added in other PRs.
This PR supports declarations and the Load & GetDimensions methods. New tests are
added.
