VkPhysicalDeviceCooperativeMatrixInfo2EXT(3)

C Specification

The VkPhysicalDeviceCooperativeMatrixInfo2EXT structure is defined as:

// Provided by VK_EXT_cooperative_matrix_maintenance1
typedef struct VkPhysicalDeviceCooperativeMatrixInfo2EXT {
    VkStructureType                sType;
    const void*                    pNext;
    VkScopeKHR                     scope;
    uint32_t                       invocations;
    uint32_t                       subgroupSize;
    VkCooperativeMatrixFlagsEXT    flags;
} VkPhysicalDeviceCooperativeMatrixInfo2EXT;

Members

sType is a VkStructureType value identifying this structure.
pNext is NULL or a pointer to a structure extending this structure.
scope is the scope of the matrices, of type VkScopeKHR.
invocations is the number of invocations within the local workgroup. invocations is ignored unless scope is VK_SCOPE_WORKGROUP_KHR.
subgroupSize is the size of the subgroup.
flags is a bitmask of VkCooperativeMatrixFlagBitsEXT selecting which class of matrix properties are being queried.

Description

If subgroupSize is equal to 0, then the properties returned will be valid for use with shaders that execute with a varying subgroup size, and the returned properties are not guaranteed to be valid for any specific effective subgroup size.

If scope is VK_SCOPE_WORKGROUP_KHR, invocations specifies the number of invocations in the local workgroup, otherwise the properties returned will be valid for all supported local workgroup sizes.

Note	If `scope` is VK_SCOPE_WORKGROUP_KHR scope, the retrieved properties will only be valid for shaders in which `invocations` is a multiple of the shader’s effective subgroup size.

Note

The intended usage of subgroupSize is:

If the matrix will be used with a pipeline that enables VK_PIPELINE_SHADER_STAGE_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT or a shader that enables VK_SHADER_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT_EXT, or a SPIR-V module version 1.6 or later with no required subgroup size specified, the application should query the properties with subgroupSize equal to 0, since the effective subgroup size is not known at pipeline creation time.
If the matrix will be used with a shader whose subgroup size is forced via VkPipelineShaderStageRequiredSubgroupSizeCreateInfo, or VkShaderRequiredSubgroupSizeCreateInfoEXT for shader objects, the application should query with subgroupSize equal to the required value.
Otherwise (the SPIR-V module version is less than 1.6, and the shader neither requests a specific subgroup size nor allows it to vary), the effective subgroup size is VkPhysicalDeviceSubgroupProperties::subgroupSize, and the application should query with that value.

Valid Usage

VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-scope-13372
scope must equal VK_SCOPE_SUBGROUP_KHR or VK_SCOPE_WORKGROUP_KHR
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-cooperativeMatrixWorkgroupScope-13373
If the VkPhysicalDeviceCooperativeMatrix2FeaturesNV::cooperativeMatrixWorkgroupScope feature is not supported, scope must not equal VK_SCOPE_WORKGROUP_KHR
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-subgroupSize-13374
If subgroupSize does not equal 0, subgroupSize must be a power of two
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-scope-13375
If scope is VK_SCOPE_SUBGROUP_KHR, subgroupSize does not equal 0, and the subgroupSizeControl feature is supported, subgroupSize must be greater or equal to minSubgroupSize
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-scope-13376
If scope is VK_SCOPE_SUBGROUP_KHR and the subgroupSizeControl feature is supported, subgroupSize must be less than or equal to maxSubgroupSize
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-scope-13377
If scope is VK_SCOPE_SUBGROUP_KHR, the subgroupSizeControl feature is not supported, and subgroupSize does not equal 0, subgroupSize must be equal to VkPhysicalDeviceSubgroupProperties::subgroupSize
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-invocations-13378
If scope is VK_SCOPE_WORKGROUP_KHR, invocations must be a power of two
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-subgroupSize-13379
If scope is VK_SCOPE_WORKGROUP_KHR, and subgroupSize does not equal 0, invocations must be a multiple of subgroupSize
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-scope-13380
If scope is VK_SCOPE_WORKGROUP_KHR, invocations must be less than or equal to cooperativeMatrixWorkgroupScopeMaxWorkgroupSize
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-invocations-13381
If scope is not VK_SCOPE_WORKGROUP_KHR, invocations must be equal 0

Valid Usage (Implicit)

VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-sType-sType
sType must be VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_COOPERATIVE_MATRIX_INFO_2_EXT
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-pNext-pNext
pNext must be NULL
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-scope-parameter
scope must be a valid VkScopeKHR value
VUID-VkPhysicalDeviceCooperativeMatrixInfo2EXT-flags-parameter
If flags is not 0, flags must be a valid combination of VkCooperativeMatrixFlagBitsEXT values

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

SPDX-License-Identifier: CC-BY-4.0

VkPhysicalDeviceCooperativeMatrixInfo2EXT(3) Manual Page

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