- When determining need for arg buffer padding, use the descriptor count provided
by the app, rather than the shader, to determine the number of slots consumed,
as the shader may only be accessing part, or even one element, of the array.
Normally, I wouldn't have bothered with this, given that we already
support the Vulkan 1.1 subgroup functionality, but a client asked for
the legacy extensions.
Previously, if a constant without DecorationSpecId occurred before the constant with DecorationSpecId 0, it would be inserted into the unique_func_constants map with key 0 (the default return value from get_decoration). This prevented us from ever emitting the declaration with [[function_constant(0)]], which produced some bizarre MSL compilation errors.
Instead, we now only insert into unique_func_constants when we know we're going to emit a [[function_constant(…)]] line.
This regressed in 41007cdc7d.
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.
It is possible in SPIR-V to declare multiple specialization constants
with the same constant ID. The most common cause of this in GLSL is
defining a spec constant, then declaring the workgroup size to use that
spec constant by its ID. But, MSL forbids defining multiple function
constants with the same function constant ID. So, we must only emit one
definition of the actual function constant (with the
`[[function_constant(id)]]` attribute); but we can point the other
variables at this one definition.
Fixes three tests in the Vulkan CTS under
`dEQP-VK.compute.basic.max_local_size_*`.
Some Metal devices have a bug with depth array textures using comparison
with explicit LoD, where the LoD given will be biased by some amount.
For these devices, we can use a gradient instead, which does not exhibit
this problem. As with the fragment demote workaround, this is only
expected to be needed until the bug is fixed in Metal.
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.
- Add CompilerMSL::Options::argument_buffers_tier as an enumeration to
allow calling app to specify platform argument buffer tier capabilities.
- Support iOS writable images in Tier2 argument buffers when specified.
Tier capabilities based on recommendations from Apple engineering.
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 storage resources can still be
written to even if the fragment is discarded. This is obviously a bug in
Metal, but bothering Apple to fix it will only fix it for newer
versions; therefore, a workaround is needed for older versions. I have
made this an option so that, in case the bug is ever fixed, the
workaround can be disabled.
This workaround is simple: if a fragment shader may discard its fragment
and writes to a storage resource, a variable representing the
`HelperInvocation` built-in is created and passed to all functions. The
flag is checked on all resource writes; writes do not occur when
`HelperInvocation` is `true`. This relies on the earlier workaround to
update `HelperInvocation` when the fragment is discarded.
Fixes at least 3 failures in the CTS.
It is possible to pass unsigned integers to `OpSMulExtended`. In that
case, we want to do a signed multiply with sign extension, so make sure
the operands are forced to be interpreted as signed.
This was an oversight on my part when I added these instructions.
Fixes the CTS test
`dEQP-VK.spirv_assembly.instruction.compute.signed_op.uint_smulextended`.
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.
