Handling native array types is not really feasible since we need to fuse
the variable declaration with the type declaration.
This is feasible in something like variable_decl, but for plain SSA
pointers, this breaks down.
If we have emitted block IO lowering at the end of vertex shader, we
will end up using the wrong name. Forcing a v_ prefix does not solve any
actual problems since the intentifier already has to be valid.
Vulkan specifies round-to-nearest-even mode to round array coordinates.
But we were using `round()`, which is round-to-nearest-away-from-zero.
Instead, use `rint()`, which is specified to perform nearest-even
rounding in MSL.
Undef values may be of struct type and may be used in constants.
Therefore, they must be interleaved with constants and types.
Fixes the rest of the Vulkan CTS test
`dEQP-VK.spirv_assembly.instruction.compute.opundef.undefined_spec_constant_composite`.
(Please excuse the churn in the reference output; it's an inevitable
result of this change.)
Some Metal devices have a bug where `simd_is_helper_thread()` won't
return true after a fragment has been discarded. We can work around this
by manually setting `gl_HelperInvocation` upon discarding a fragment.
This is fairly unintrusive, so it is enabled by default. I've made it an
option so that, when the bug is fixed, we can disable it.
MSL inherits the behavior of C where arithmetic on small types are
implicitly converted to int. SPIR-V does not have this behavior, so make
sure that arithmetic results are handled correctly.
restrict was supported, but it broke in MSL 3.0. __restrict works on all
versions, so opt for that instead.
Also check for RestrictPointer decoration and refactor to_restrict() to
not take optional parameter to make it more obvious when implied space
character is added.
Using vertex-style stage input is complex, and it doesn't support
nesting of structures or arrays. By using raw buffer input instead, we
get this support "for free," and everything becomes much simpler.
Arguably, this is the way I should've done this in the first place.
Eventually, I'd like to make this the default, and then remove the
option altogether. (And I still need to do that with
`multi_patch_workgroup`...)
Should help fix 66 tests in the Vulkan CTS, under the following trees:
- `dEQP-VK.pipeline.*.interface_matching.*`
- `dEQP-VK.tessellation.user_defined_io.*`
- `dEQP-VK.clipping.user_defined.*`
When storing to local variable (eg. OpCopyLogical), the
default device address space used during casts is illegal.
Determine correct address space based on variable type.
- Add CompilerMSL::emit_binary_ptr_op() and to_ptr_expression()
to emit binary pointer op. Compare matrix addresses without automatic
transpose() conversion, to avoid error taking address of temporary copy.
- Add Compiler::add_active_interface_variable() to also track active
interface vars in the entry point for SPIR-V 1.4 and above.
- For OpPtrAccessChain that ends in array element, use Element
as offset to existing index, otherwise it will access into
array dimension that doesn't exist.
- Dereference pointer function call arguments. Ultimately, this
dereferencing is actually backwards, and in future, we should aim
to properly support passing pointer variables between functions,
but such a refactoring was beyond the scope here.
- Use [] to declare array of pointers, as array<T*> is not supported in MSL.
- Add unit test shaders.
Speculate that we can modify the SSA value in-place. As long as it is
not used after the modify, this is fine.
Also need to make sure we don't attempt to RMW something that is
impossible to modify.
Just like we try to fixup struct names for block types, inner structs
can be "anonymous" structs. HLSL codegen from DXC tends to emit this,
and emitting dummy struct names tends to break GL linkage on some
drivers.
This allows two variables of the same struct type to be flattened
into the same interface struct without a member name conflict.
Add shaders-msl/frag/in_block_with_multiple_structs_of_same_type.frag
unit test shader to demonstrate this.
Makes codegen from typical D3D emulation SPIR-V more readable.
Also makes cross compilation with NotEqual more sensible.
It's very rare to actually need the strict NaN-checks in practice.
Also, glslang now emits UnordNotEqual by default it seems, so give up
trying to assume OrdNotEqual. Harmonize for UnordNotEqual as the sane
default.
We were passing arrays by value which the compiler fails to optimize,
causing abyssal performance. To fix this, we need to consider that
descriptors can be in constant or const device address spaces.
Also, lone descriptors are passed by value, so we explicitly remove address
space qualifiers.
One failure case is when shader passes a texture/sampler array as an
argument. It's all UniformConstant in SPIR-V, but in MSL it might be
thread, const device or constant, so that won't work ...
Global variable use works fine though, and that should cover 99.9999999%
of use cases.
Need this to be context sensitive, since array of block-like struct is
template, but struct of block-like array is C-style.
Also, test a mix and match, so we have constant array of block-like
struct with array inside. :v
Emit synthetic functions before function constants.
Support use of spvQuantizeToF16() in function constants for numerical
behavior consistency with the op code.
Ensure subnormal results from OpQuantizeToF16 are flushed to zero per SPIR-V spec.
Adjust SPIRV-Cross unit test reference shaders to accommodate these changes.
Any MSL reference shader that inclues a synthetic function is affected,
since the location it is emitted has changed.
Based on CTS testing, math optimizations between MSL and Vulkan are inconsistent.
In some cases, enabling MSL's fast-math compilation option matches Vulkan's math
results. In other cases, disabling it does. Broadly enabling or disabling fast-math
across all shaders results in some CTS test failures either way.
To fix this, selectively enable/disable fast-math optimizations in the MSL code,
using metal::fast and metal::precise function namespaces, where supported, and
the [[clang::optnone]] function attribute otherwise.
Adjust SPIRV-Cross unit test reference shaders to accommodate these changes.
