This is somewhat awkward to support, but the best effort we can do here
is to analyze various Load/Store opcodes and deduce the ideal overall
alignment based on this. This is not a 100% perfect solution, but should
be correct for any reasonable use case.
Also fix various nitpicks with BDA support while I'm at it.
Promote to short instead and do simple casts on load/store instead.
Not 100% complete fix since structs can contain booleans, but this is
getting into pretty ridiculously complicated territory.
We'll need to force a temporary and mark it as precise.
MSL is a little weird here, but we can piggyback on top of the invariant
float math option here to force fma() operations everywhere.
Need special workarounds to handle array load/store since array size is
unsized in GLSL, and array copy is not possible.
Also, consider bitcast for scalar loads and stores.
Fairly minor differences, so can keep them side by side without too much
effort. NV support is effectively deprecated now however.
- Add OpConvertUToAccelerationStructureKHR
- Ignore/Terminate ray is now a terminator in KHR, but a call in NV.
- Fix some bugs with reportIntersection.
`half` cannot be bitcasted to `float`, because the two types are not the
same size. Use an expanding cast instead.
We were already doing this for stores to the tessellation levels; why I
didn't also do this for loads is beyond me.
- Do not silently drop reserved identifiers in the parser. This makes it
possible to reflect identifiers which are reserved by the
cross-compiler module.
- Instead of dropping the name, emit _RESERVED_IDENTIFIER_FIXUP in the
source to make it clear that a name has been rewritten.
- Document what is reserved and not.
On MSL, the compiler refuses to allow access chains into a normal vector type.
What happens in practice instead is a read-modify-write where a vector type is
loaded, modified and written back.
The workaround is to convert a vector into a pointer-to-scalar before
the access chain continues to add the scalar index.
When inside a loop, treat any read of outer expressions to happen
multiple times, forcing a temporary of said outer expressions.
This avoids the problem where we can end up relying on loop-invariant code motion to happen in the
compiler when converting optimized shaders.
When loading and storing array types which belong to buffer objects, we
need to treat these values as not being value types. Also, need to
handle array load/store from/to more address space combinations.
