Games using D3D idioms can join images and samplers when a shader
executes, instead of baking them into a combined sampler image. This is
also possible on Vulkan.
One approach to this solution would be to use separate samplers on
Vulkan and leave this unimplemented on OpenGL, but we can't do this
because there's no consistent way of determining which constant buffer
holds a sampler and which one an image. We could in theory find the
first bit and if it's in the TIC area, it's an image; but this falls
apart when an image or sampler handle use an index of zero.
The used approach is to track for a LOP.OR operation (this is done at an
IR level, not at an ISA level), track again the constant buffers used as
source and store this pair. Then, outside of shader execution, join
the sample and image pair with a bitwise or operation.
This approach won't work on games that truly use separate samplers in a
meaningful way. For example, pooling textures in a 2D array and
determining at runtime what sampler to use.
This invalidates OpenGL's disk shader cache :)
- Used mostly by D3D ports to Switch
Geometry shaders built from Nvidia's compiler check for bits[16:23] to
be less than or equal to 0 with VSETP to default to a "safe" value of
0x8000'0000 (safe from hardware's perspective). To avoid hitting this
path in the shader, return 0x00ff'0000 from S2R INVOCATION_INFO.
This seems to be the maximum number of vertices a geometry shader can
emit in a primitive.
Hardware S2R special registers match gl_Thread*MaskNV. We can trivially
implement these using Nvidia's extension on OpenGL or naively stubbing
them with the ARB instructions to match. This might cause issues if the
host device warp size doesn't match Nvidia's. That said, this is
unlikely on proper shaders.
Refer to the attached url for more documentation about these flags.
https://www.khronos.org/registry/OpenGL/extensions/NV/NV_shader_thread_group.txt
Signed integer addition overflow might be undefined behavior. It's free
to change operations to UAdd and use unsigned integers to avoid
potential bugs.
P2R CC takes the state of condition codes and puts them into a register.
We already have this implemented for PR (predicates). This commit
implements CC over that.
The encoding for negation and absolute value was wrong.
Extracting is now done manually. Similar instructions having different
encodings is the rule, not the exception. To keep sanity and readability
I preferred to extract the desired bit manually.
This is implemented against nxas:
8dbc389957/table.h (L68)
That is itself tested against nvdisasm (Nvidia's official disassembler).
This allows deducing some properties from the texture instruction before
asking the runtime. By doing this we can handle type mismatches in some
instructions from the renderer instead of the shader decoder.
Fixes texelFetch issues with games using 2D texture instructions on a 1D
sampler.
Some variables aren't used, so we can remove these.
Unfortunately, diagnostics are still reported on structured bindings
even when annotated with [[maybe_unused]], so we need to unpack the
elements that we want to use manually.
Allows reporting more cases where logic errors may exist, such as
implicit fallthrough cases, etc.
We currently ignore unused parameters, since we currently have many
cases where this is intentional (virtual interfaces).
While we're at it, we can also tidy up any existing code that causes
warnings. This also uncovered a few bugs as well.
Implements the common usages for VMNMX. Inputs with a different size
than 32 bits are not supported and sign mismatches aren't supported
either.
VMNMX works as follows:
It grabs Ra and Rb and applies a maximum/minimum on them (this is
defined by .MX), having in mind the input sign. This result can then be
saturated. After the intermediate result is calculated, it applies
another operation on it using Rc. These operations are merges,
accumulations or another min/max pass.
This instruction allows to implement with a more flexible approach GCN's
min3 and max3 instructions (for instance).
Since commit e22816a5bb we handle type mismatches from the CPU.
We don't need to hack our shader decoder due to game bugs anymore.
Removed in this commit.
Reimplements I2I adding sign extension, saturation (clamp source value
to the destination), selection and destination sizes that are not 32
bits wide.
It doesn't implement CC yet.
Implements a reduction operation. It's an atomic operation that doesn't
return a value.
This commit introduces another primitive because some shading languages
might have a primitive for reduction operations.
