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
Introduces an idea of a recompilation making forward progress.
There are some extreme edge cases where we need more than 3 loops, but
only allow this in specific circumstances where we can reason about
forward progress being made.
Adds "In" postfix to the "gl_TessCoord" on entry point arguments decompilation stage if built in type is "BuiltInTessCoord" and execution mode is "ExecutionModeQuads". And declares shadow variable "gl_TessCoord" on entry point declarations.
Fragment shaders that require explicit early fragment tests are incompatible
with specifying depth and stencil values within the shader. If explicit early
fragment tests is specified, remove the depth and stencil outputs from the
output structure, and replace them with dummy local variables.
Add CompilerMSL:uses_explicit_early_fragment_test() function to consolidate
testing for whether early fragment tests are required.
Add two unit tests for depth-out with, and without, early fragment tests.
SPIR-V allows an image to be marked as a depth image, but with a non-depth
format. Such images should be read or sampled as vectors instead of scalars,
except when they are subject to compare operations.
Don't mark an OpSampledImage as using a compare operation just because the
image contains a depth marker. Instead, require that a compare operation
is actually used on that image.
Compiler::image_is_comparison() was really testing whether an image is a
depth image, since it incorporates the depth marker. Rename that function
to is_depth_image(), to clarify what it is really testing.
In Compiler::is_depth_image(), do not treat an image as a depth image
if it has been explicitly marked with a color format, unless the image
is subject to compare operations.
In CompilerMSL::to_function_name(), test for compare operations
specifically, rather than assuming them from the depth-image marker.
CompilerGLSL and CompilerMSL still contain a number of internal tests that
use is_depth_image() both for testing for a depth image, and for testing
whether compare operations are being used. I've left these as they are
for now, but these should be cleaned up at some point.
Add unit tests for fetch/sample depth images with color formats and no compare ops.
Only emit user(locnN) for tess builtin input variables, and allow output builtin
to emit user(clip/cullN). Previously, output builtin would emit location if
input builtin also existed.
Previous test for SPIRVCrossDecorationPhysicalTypePacked on parent struct
when unpacking member struct was too restrictive, and not needed as long
as padding compensates.
Populate member_type_index_redirection as reverse lookup, not forward lookup.
Move use of member_type_index_redirection from CompilerMSL::to_member_reference()
to CompilerGLSL::access_chain_internal() to access all redirected type info,
not just name.
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.
Additional usecases include array and vector indexing, variable declarations,
loop initializers, function return values, switch statement evaluations,
and various specialized MSL operations.
Ultimately, we might consider refactoring CompilerMSL::to_expression()
to always take into consideration possible unpacking behavior.
Refactor CompilerGLSL::to_enclosed_unpacked_expression()
for conciseness and consistency with similar functionality.
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.
Add spvQuantizeToF16() family of synthetic functions to convert
from float to half and back again, and add function attribute
[[clang::optnone]] to honor infinities during conversions.
Adjust SPIRV-Cross unit test reference shaders to accommodate these changes.
Add [[clang::optnone]] attribute to spvF*() functions used for handling
floating point operations decorated with DecorationNoContraction.
Just using precise::fma() did not work.
Adjust SPIRV-Cross unit test reference shaders to accommodate these changes.
Matching output/input struct member types between shader stages could fail if
a location is shared between members, each using different components of that
location, because the member vecsize was only stored once for the location.
Add MSLShaderInput::component member.
Use LocationComponentPair to key inputs_by_location, instead of just location.
ensure_correct_input_type() pass component value as well as location.
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.
Add test shader for new functionality.
Add legacy test reference shader for unrelated buffer-bitcast
test, that doesn't seem to have been added previously.
When gl_Position is defined by SPIR-V, but neither used nor initialized,
it appeared twice in the MSL output, as gl_Position and glPosition_1.
The existing tests for whether an output is active check only that it is
used by an op, or initialized. Adding the implicit gl_Position also marked
the existing gl_Position as active, duplicating the output variable.
Fix is that when checking for the need to add an implicit gl_Position
output, also check if the var is already defined in the shader,
and just needs to be marked as active.
Add test shader.
Previous casting in constant expressions used as_type<> between
types of different overall sizes.
Add check for overall size (width * vecsize) to ensure as_type<> will work,
otherwise use regular cast. Also beef up test of integer values to also check
vecsize, and use regular casts for those.