VkPhysicalDeviceSubgroupProperties

The VkPhysicalDeviceSubgroupProperties structure is defined as:

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

• sType is a VkStructureType value identifying this structure.
• pNext is NULL or a pointer to a structure extending this 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 the VkPhysicalDeviceProperties2 structure passed to vkGetPhysicalDeviceProperties2, it is filled in with each corresponding implementation-dependent property.

If supportedOperations includes VK_SUBGROUP_FEATURE_QUAD_BIT, or the shaderSubgroupUniformControlFlow feature is enabled, subgroupSize must be greater than or equal to 4.

If the shaderQuadControl feature is supported, supportedOperations must include VK_SUBGROUP_FEATURE_QUAD_BIT.

If VK_KHR_shader_subgroup_rotate is supported, and the implementation advertises support with a VkExtensionProperties::specVersion greater than or equal to 2, and the shaderSubgroupRotate feature is supported, VK_SUBGROUP_FEATURE_ROTATE_BIT must be returned in VkPhysicalDeviceSubgroupProperties::supportedOperations. If VK_KHR_shader_subgroup_rotate is supported, and the implementation advertises support with a VkExtensionProperties::specVersion greater than or equal to 2, and the shaderSubgroupRotateClustered feature is supported, VK_SUBGROUP_FEATURE_ROTATE_CLUSTERED_BIT must be returned in VkPhysicalDeviceSubgroupProperties::supportedOperations.