C Specification

Possible values of the flags member of VkPipelineShaderStageCreateInfo specifying how a pipeline shader stage is created, are:

typedef enum VkPipelineShaderStageCreateFlagBits {
    VK_PIPELINE_SHADER_STAGE_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT_EXT = 0x00000001,
    VK_PIPELINE_SHADER_STAGE_CREATE_REQUIRE_FULL_SUBGROUPS_BIT_EXT = 0x00000002,
    VK_PIPELINE_SHADER_STAGE_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VkPipelineShaderStageCreateFlagBits;

Description

  • VK_PIPELINE_SHADER_STAGE_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT_EXT specifies that the SubgroupSize may vary in the shader stage.

  • VK_PIPELINE_SHADER_STAGE_CREATE_REQUIRE_FULL_SUBGROUPS_BIT_EXT specifies that the subgroup sizes must be launched with all invocations active in the compute stage.

Note

If VK_PIPELINE_SHADER_STAGE_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT_EXT and VK_PIPELINE_SHADER_STAGE_CREATE_REQUIRE_FULL_SUBGROUPS_BIT_EXT are specified and minSubgroupSize does not equal maxSubgroupSize and no required subgroup size is specified, then the only way to guarantee that the 'X' dimension of the local workgroup size is a multiple of SubgroupSize is to make it a multiple of maxSubgroupSize. Under these conditions, you are guaranteed full subgroups but not any particular subgroup size.

See Also

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 (c) 2014-2019 Khronos Group. This work is licensed under a Creative Commons Attribution 4.0 International License.