Vulkan.Extensions.VK_EXT_subgroup_size_control

Name

VK_EXT_subgroup_size_control - device extension

VK_EXT_subgroup_size_control

Name String

VK_EXT_subgroup_size_control

Extension Type

Device extension

Registered Extension Number

226

Revision

2

Extension and Version Dependencies

• Requires Vulkan 1.1

Contact

• Neil Henning @sheredom%0A<<Here describe the issue or question you have about the VK_EXT_subgroup_size_control extension> >

Other Extension Metadata

Last Modified Date

2019-03-05

Contributors

• Jeff Bolz, NVIDIA
• Jason Ekstrand, Intel
• Sławek Grajewski, Intel
• Jesse Hall, Google
• Neil Henning, AMD
• Daniel Koch, NVIDIA
• Jeff Leger, Qualcomm
• Graeme Leese, Broadcom
• Allan MacKinnon, Google
• Mariusz Merecki, Intel
• Graham Wihlidal, Electronic Arts

Description

This extension enables an implementation to control the subgroup size by allowing a varying subgroup size and also specifying a required subgroup size.

It extends the subgroup support in Vulkan 1.1 to allow an implementation to expose a varying subgroup size. Previously Vulkan exposed a single subgroup size per physical device, with the expectation that implementations will behave as if all subgroups have the same size. Some implementations may dispatch shaders with a varying subgroup size for different subgroups. As a result they could implicitly split a large subgroup into smaller subgroups or represent a small subgroup as a larger subgroup, some of whose invocations were inactive on launch.

To aid developers in understanding the performance characteristics of their programs, this extension exposes a minimum and maximum subgroup size that a physical device supports and a pipeline create flag to enable that pipeline to vary its subgroup size. If enabled, any SubgroupSize decorated variables in the SPIR-V shader modules provided to pipeline creation may vary between the minimum and maximum subgroup sizes.

An implementation is also optionally allowed to support specifying a required subgroup size for a given pipeline stage. Implementations advertise which stages support a required subgroup size, and any pipeline of a supported stage can be passed a PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT structure to set the subgroup size for that shader stage of the pipeline. For compute shaders, this requires the developer to query the maxComputeWorkgroupSubgroups and ensure that:

\[s = { WorkGroupSize.x \times WorkGroupSize.y \times WorkgroupSize.z \leq SubgroupSize \times maxComputeWorkgroupSubgroups }\]

Developers can also specify a new pipeline shader stage create flag that requires the implementation to have fully populated subgroups within local workgroups. This requires the workgroup size in the X dimension to be a multiple of the subgroup size.

New Structures

• Extending PhysicalDeviceFeatures2, DeviceCreateInfo:

  • PhysicalDeviceSubgroupSizeControlFeaturesEXT

• Extending PhysicalDeviceProperties2:

  • PhysicalDeviceSubgroupSizeControlPropertiesEXT

• Extending PipelineShaderStageCreateInfo:

  • PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

New Enum Constants

• EXT_SUBGROUP_SIZE_CONTROL_EXTENSION_NAME

• EXT_SUBGROUP_SIZE_CONTROL_SPEC_VERSION

• Extending PipelineShaderStageCreateFlagBits:

  • PIPELINE_SHADER_STAGE_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT_EXT
  • PIPELINE_SHADER_STAGE_CREATE_REQUIRE_FULL_SUBGROUPS_BIT_EXT

• Extending StructureType:

  • STRUCTURE_TYPE_PHYSICAL_DEVICE_SUBGROUP_SIZE_CONTROL_FEATURES_EXT
  • STRUCTURE_TYPE_PHYSICAL_DEVICE_SUBGROUP_SIZE_CONTROL_PROPERTIES_EXT
  • STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_REQUIRED_SUBGROUP_SIZE_CREATE_INFO_EXT

Version History

• Revision 1, 2019-03-05 (Neil Henning)

  • Initial draft

• Revision 2, 2019-07-26 (Jason Ekstrand)

  • Add the missing PhysicalDeviceSubgroupSizeControlFeaturesEXT for querying subgroup size control features.

See Also

PhysicalDeviceSubgroupSizeControlFeaturesEXT, PhysicalDeviceSubgroupSizeControlPropertiesEXT, PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Document Notes

For more information, see the Vulkan Specification

This page is a generated document. Fixes and changes should be made to the generator scripts, not directly.

Documentation

data PhysicalDeviceSubgroupSizeControlFeaturesEXT

VkPhysicalDeviceSubgroupSizeControlFeaturesEXT - Structure describing the subgroup size control features that can be supported by an implementation

Members

This structure describes the following features:

Description

If the PhysicalDeviceSubgroupSizeControlFeaturesEXT structure is included in the pNext chain of the PhysicalDeviceFeatures2 structure passed to getPhysicalDeviceFeatures2, it is filled in to indicate whether each corresponding feature is supported. PhysicalDeviceSubgroupSizeControlFeaturesEXT can also be used in the pNext chain of DeviceCreateInfo to selectively enable these features.

Note

The PhysicalDeviceSubgroupSizeControlFeaturesEXT structure was added in version 2 of the VK_EXT_subgroup_size_control extension. Version 1 implementations of this extension will not fill out the features structure but applications may assume that both subgroupSizeControl and computeFullSubgroups are supported if the extension is supported. (See also the Feature Requirements section.) Applications are advised to add a PhysicalDeviceSubgroupSizeControlFeaturesEXT structure to the pNext chain of DeviceCreateInfo to enable the features regardless of the version of the extension supported by the implementation. If the implementation only supports version 1, it will safely ignore the PhysicalDeviceSubgroupSizeControlFeaturesEXT structure.

Valid Usage (Implicit)

See Also

VK_EXT_subgroup_size_control, Bool32, StructureType

Constructors

PhysicalDeviceSubgroupSizeControlFeaturesEXT

Fields

• subgroupSizeControl :: Bool

  subgroupSizeControl indicates whether the implementation supports controlling shader subgroup sizes via the PIPELINE_SHADER_STAGE_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT_EXT flag and the PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT structure.

• computeFullSubgroups :: Bool

  computeFullSubgroups indicates whether the implementation supports requiring full subgroups in compute shaders via the PIPELINE_SHADER_STAGE_CREATE_REQUIRE_FULL_SUBGROUPS_BIT_EXT flag.

Instances

Eq PhysicalDeviceSubgroupSizeControlFeaturesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

(==) :: PhysicalDeviceSubgroupSizeControlFeaturesEXT -> PhysicalDeviceSubgroupSizeControlFeaturesEXT -> Bool

(/=) :: PhysicalDeviceSubgroupSizeControlFeaturesEXT -> PhysicalDeviceSubgroupSizeControlFeaturesEXT -> Bool

Show PhysicalDeviceSubgroupSizeControlFeaturesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

showsPrec :: Int -> PhysicalDeviceSubgroupSizeControlFeaturesEXT -> ShowS

show :: PhysicalDeviceSubgroupSizeControlFeaturesEXT -> String

showList :: [PhysicalDeviceSubgroupSizeControlFeaturesEXT] -> ShowS

Storable PhysicalDeviceSubgroupSizeControlFeaturesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

sizeOf :: PhysicalDeviceSubgroupSizeControlFeaturesEXT -> Int

alignment :: PhysicalDeviceSubgroupSizeControlFeaturesEXT -> Int

peekElemOff :: Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> Int -> IO PhysicalDeviceSubgroupSizeControlFeaturesEXT

pokeElemOff :: Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> Int -> PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO ()

peekByteOff :: Ptr b -> Int -> IO PhysicalDeviceSubgroupSizeControlFeaturesEXT

pokeByteOff :: Ptr b -> Int -> PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO ()

peek :: Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO PhysicalDeviceSubgroupSizeControlFeaturesEXT

poke :: Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO ()

FromCStruct PhysicalDeviceSubgroupSizeControlFeaturesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

peekCStruct :: Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO PhysicalDeviceSubgroupSizeControlFeaturesEXT

ToCStruct PhysicalDeviceSubgroupSizeControlFeaturesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

withCStruct :: PhysicalDeviceSubgroupSizeControlFeaturesEXT -> (Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO b) -> IO b

pokeCStruct :: Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO b -> IO b

withZeroCStruct :: (Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO b) -> IO b

pokeZeroCStruct :: Ptr PhysicalDeviceSubgroupSizeControlFeaturesEXT -> IO b -> IO b

cStructSize :: Int

cStructAlignment :: Int

Zero PhysicalDeviceSubgroupSizeControlFeaturesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

zero :: PhysicalDeviceSubgroupSizeControlFeaturesEXT

data PhysicalDeviceSubgroupSizeControlPropertiesEXT

VkPhysicalDeviceSubgroupSizeControlPropertiesEXT - Structure describing the control subgroup size properties of an implementation

Description

If the PhysicalDeviceSubgroupSizeControlPropertiesEXT structure is included in the pNext chain of the PhysicalDeviceProperties2 structure passed to getPhysicalDeviceProperties2, it is filled in with each corresponding implementation-dependent property.

If PhysicalDeviceSubgroupProperties::supportedOperations includes https://www.khronos.org/registry/vulkan/specs/1.2-extensions/html/vkspec.html#features-subgroup-quad, minSubgroupSize must be greater than or equal to 4.

Valid Usage (Implicit)

See Also

VK_EXT_subgroup_size_control, ShaderStageFlags, StructureType

Constructors

PhysicalDeviceSubgroupSizeControlPropertiesEXT

Fields

• minSubgroupSize :: Word32

  minSubgroupSize is the minimum subgroup size supported by this device. minSubgroupSize is at least one if any of the physical device’s queues support QUEUE_GRAPHICS_BIT or QUEUE_COMPUTE_BIT. minSubgroupSize is a power-of-two. minSubgroupSize is less than or equal to maxSubgroupSize. minSubgroupSize is less than or equal to subgroupSize.

• maxSubgroupSize :: Word32

  maxSubgroupSize is the maximum subgroup size supported by this device. maxSubgroupSize is at least one if any of the physical device’s queues support QUEUE_GRAPHICS_BIT or QUEUE_COMPUTE_BIT. maxSubgroupSize is a power-of-two. maxSubgroupSize is greater than or equal to minSubgroupSize. maxSubgroupSize is greater than or equal to subgroupSize.

• maxComputeWorkgroupSubgroups :: Word32

  maxComputeWorkgroupSubgroups is the maximum number of subgroups supported by the implementation within a workgroup.

• requiredSubgroupSizeStages :: ShaderStageFlags

  requiredSubgroupSizeStages is a bitfield of what shader stages support having a required subgroup size specified.

Instances

Eq PhysicalDeviceSubgroupSizeControlPropertiesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

(==) :: PhysicalDeviceSubgroupSizeControlPropertiesEXT -> PhysicalDeviceSubgroupSizeControlPropertiesEXT -> Bool

(/=) :: PhysicalDeviceSubgroupSizeControlPropertiesEXT -> PhysicalDeviceSubgroupSizeControlPropertiesEXT -> Bool

Show PhysicalDeviceSubgroupSizeControlPropertiesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

showsPrec :: Int -> PhysicalDeviceSubgroupSizeControlPropertiesEXT -> ShowS

show :: PhysicalDeviceSubgroupSizeControlPropertiesEXT -> String

showList :: [PhysicalDeviceSubgroupSizeControlPropertiesEXT] -> ShowS

Storable PhysicalDeviceSubgroupSizeControlPropertiesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

sizeOf :: PhysicalDeviceSubgroupSizeControlPropertiesEXT -> Int

alignment :: PhysicalDeviceSubgroupSizeControlPropertiesEXT -> Int

peekElemOff :: Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> Int -> IO PhysicalDeviceSubgroupSizeControlPropertiesEXT

pokeElemOff :: Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> Int -> PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO ()

peekByteOff :: Ptr b -> Int -> IO PhysicalDeviceSubgroupSizeControlPropertiesEXT

pokeByteOff :: Ptr b -> Int -> PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO ()

peek :: Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO PhysicalDeviceSubgroupSizeControlPropertiesEXT

poke :: Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO ()

FromCStruct PhysicalDeviceSubgroupSizeControlPropertiesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

peekCStruct :: Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO PhysicalDeviceSubgroupSizeControlPropertiesEXT

ToCStruct PhysicalDeviceSubgroupSizeControlPropertiesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

withCStruct :: PhysicalDeviceSubgroupSizeControlPropertiesEXT -> (Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO b) -> IO b

pokeCStruct :: Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO b -> IO b

withZeroCStruct :: (Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO b) -> IO b

pokeZeroCStruct :: Ptr PhysicalDeviceSubgroupSizeControlPropertiesEXT -> IO b -> IO b

cStructSize :: Int

cStructAlignment :: Int

Zero PhysicalDeviceSubgroupSizeControlPropertiesEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

zero :: PhysicalDeviceSubgroupSizeControlPropertiesEXT

data PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

VkPipelineShaderStageRequiredSubgroupSizeCreateInfoEXT - Structure specifying the required subgroup size of a newly created pipeline shader stage

Valid Usage

Description

If a PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT structure is included in the pNext chain of PipelineShaderStageCreateInfo, it specifies that the pipeline shader stage being compiled has a required subgroup size.

Valid Usage (Implicit)

See Also

VK_EXT_subgroup_size_control, StructureType

Constructors

PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Fields

• requiredSubgroupSize :: Word32

  requiredSubgroupSize must be a power-of-two integer

  requiredSubgroupSize must be greater or equal to minSubgroupSize

  requiredSubgroupSize must be less than or equal to maxSubgroupSize

Instances

Eq PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

(==) :: PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> Bool

(/=) :: PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> Bool

Show PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

showsPrec :: Int -> PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> ShowS

show :: PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> String

showList :: [PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT] -> ShowS

Storable PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

sizeOf :: PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> Int

alignment :: PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> Int

peekElemOff :: Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> Int -> IO PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

pokeElemOff :: Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> Int -> PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO ()

peekByteOff :: Ptr b -> Int -> IO PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

pokeByteOff :: Ptr b -> Int -> PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO ()

peek :: Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

poke :: Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO ()

FromCStruct PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

peekCStruct :: Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

ToCStruct PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

withCStruct :: PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> (Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO b) -> IO b

pokeCStruct :: Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO b -> IO b

withZeroCStruct :: (Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO b) -> IO b

pokeZeroCStruct :: Ptr PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT -> IO b -> IO b

cStructSize :: Int

cStructAlignment :: Int

Zero PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

Defined in Vulkan.Extensions.VK_EXT_subgroup_size_control

Methods

zero :: PipelineShaderStageRequiredSubgroupSizeCreateInfoEXT

type EXT_SUBGROUP_SIZE_CONTROL_SPEC_VERSION = 2

pattern EXT_SUBGROUP_SIZE_CONTROL_SPEC_VERSION :: forall a. Integral a => a

type EXT_SUBGROUP_SIZE_CONTROL_EXTENSION_NAME = "VK_EXT_subgroup_size_control"

pattern EXT_SUBGROUP_SIZE_CONTROL_EXTENSION_NAME :: forall a. (Eq a, IsString a) => a