# VkPhysicalDeviceSubgroupProperties(3) Manual Page

## Name

VkPhysicalDeviceSubgroupProperties - Structure describing subgroup support for an implementation

## C Specification

The `VkPhysicalDeviceSubgroupProperties` structure is defined as:

    typedef struct VkPhysicalDeviceSubgroupProperties {
        VkStructureType           sType;
        void*                     pNext;
        uint32_t                  subgroupSize;
        VkShaderStageFlags        supportedStages;
        VkSubgroupFeatureFlags    supportedOperations;
        VkBool32                  quadOperationsInAllStages;
    } VkPhysicalDeviceSubgroupProperties;

## Members

The members of the `VkPhysicalDeviceSubgroupProperties` structure describe the following implementation-dependent limits:

## Description

- `sType` is the type of this structure.

- `pNext` is `NULL` or a pointer to an extension-specific structure.

- `subgroupSize` is the default number of invocations in each subgroup. `subgroupSize` is at least 1 if any of the physical device’s queues support `VK_QUEUE_GRAPHICS_BIT` or `VK_QUEUE_COMPUTE_BIT`. `subgroupSize` is a power-of-two.

- `supportedStages` is a bitfield of VkShaderStageFlagBits describing the shader stages that group operations with subgroup scope are supported in. `supportedStages` will have the `VK_SHADER_STAGE_COMPUTE_BIT` bit set if any of the physical device’s queues support `VK_QUEUE_COMPUTE_BIT`.

- `supportedOperations` is a bitmask of VkSubgroupFeatureFlagBits specifying the sets of group operations with subgroup scope supported on this device. `supportedOperations` will have the `VK_SUBGROUP_FEATURE_BASIC_BIT` bit set if any of the physical device’s queues support `VK_QUEUE_GRAPHICS_BIT` or `VK_QUEUE_COMPUTE_BIT`.

- `quadOperationsInAllStages` is a boolean specifying whether quad group operations are available in all stages, or are restricted to fragment and compute stages.

If the `VkPhysicalDeviceSubgroupProperties` structure is included in the `pNext` chain of VkPhysicalDeviceProperties2, it is filled with the implementation-dependent limits.

If `supportedOperations` includes `VK_SUBGROUP_FEATURE_QUAD_BIT`, `subgroupSize` must be greater than or equal to 4.

Valid Usage (Implicit)

- `sType` must be `VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_SUBGROUP_PROPERTIES`

## See Also

`VkBool32`, VkShaderStageFlags, VkStructureType, VkSubgroupFeatureFlags

## Document Notes

For more information, see the Vulkan Specification

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.

## Copyright

Copyright (c) 2014-2020 Khronos Group. This work is licensed under a Creative Commons Attribution 4.0 International License.