registry/vulkan/appendices/VK_AMD_shader_core_properties.txt

// Copyright (c) 2018-2020 Advanced Micro Devices, Inc.
//
// SPDX-License-Identifier: CC-BY-4.0

include::{generated}/meta/{refprefix}VK_AMD_shader_core_properties.txt[]

=== Other Extension Metadata

*Last Modified Date*::
    2019-06-25
*IP Status*::
    No known IP claims.
*Contributors*::
  - Martin Dinkov, AMD
  - Matthaeus G. Chajdas, AMD

=== Description

This extension exposes shader core properties for a target physical device
through the `apiext:VK_KHR_get_physical_device_properties2` extension.
Please refer to the example below for proper usage.

include::{generated}/interfaces/VK_AMD_shader_core_properties.txt[]

=== Examples

This example retrieves the shader core properties for a physical device.

[source,c++]
----------------------------------------
extern VkInstance       instance;

PFN_vkGetPhysicalDeviceProperties2 pfnVkGetPhysicalDeviceProperties2 =
    reinterpret_cast<PFN_vkGetPhysicalDeviceProperties2>
    (vkGetInstanceProcAddr(instance, "vkGetPhysicalDeviceProperties2") );

VkPhysicalDeviceProperties2             general_props;
VkPhysicalDeviceShaderCorePropertiesAMD shader_core_properties;

shader_core_properties.pNext = nullptr;
shader_core_properties.sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_SHADER_CORE_PROPERTIES_AMD;

general_props.pNext = &shader_core_properties;
general_props.sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_PROPERTIES_2;

// After this call, shader_core_properties has been populated
pfnVkGetPhysicalDeviceProperties2(device, &general_props);

printf("Number of shader engines: %d\n",
    m_shader_core_properties.shader_engine_count =
    shader_core_properties.shaderEngineCount;
printf("Number of shader arrays: %d\n",
    m_shader_core_properties.shader_arrays_per_engine_count =
    shader_core_properties.shaderArraysPerEngineCount;
printf("Number of CUs per shader array: %d\n",
    m_shader_core_properties.compute_units_per_shader_array =
    shader_core_properties.computeUnitsPerShaderArray;
printf("Number of SIMDs per compute unit: %d\n",
    m_shader_core_properties.simd_per_compute_unit =
    shader_core_properties.simdPerComputeUnit;
printf("Number of wavefront slots in each SIMD: %d\n",
    m_shader_core_properties.wavefronts_per_simd =
    shader_core_properties.wavefrontsPerSimd;
printf("Number of threads per wavefront: %d\n",
    m_shader_core_properties.wavefront_size =
    shader_core_properties.wavefrontSize;
printf("Number of physical SGPRs per SIMD: %d\n",
    m_shader_core_properties.sgprs_per_simd =
    shader_core_properties.sgprsPerSimd;
printf("Minimum number of SGPRs that can be allocated by a wave: %d\n",
    m_shader_core_properties.min_sgpr_allocation =
    shader_core_properties.minSgprAllocation;
printf("Number of available SGPRs: %d\n",
    m_shader_core_properties.max_sgpr_allocation =
    shader_core_properties.maxSgprAllocation;
printf("SGPRs are allocated in groups of this size: %d\n",
    m_shader_core_properties.sgpr_allocation_granularity =
    shader_core_properties.sgprAllocationGranularity;
printf("Number of physical VGPRs per SIMD: %d\n",
    m_shader_core_properties.vgprs_per_simd =
    shader_core_properties.vgprsPerSimd;
printf("Minimum number of VGPRs that can be allocated by a wave: %d\n",
    m_shader_core_properties.min_vgpr_allocation =
    shader_core_properties.minVgprAllocation;
printf("Number of available VGPRs: %d\n",
    m_shader_core_properties.max_vgpr_allocation =
    shader_core_properties.maxVgprAllocation;
printf("VGPRs are allocated in groups of this size: %d\n",
    m_shader_core_properties.vgpr_allocation_granularity =
    shader_core_properties.vgprAllocationGranularity;
----------------------------------------


=== Version History

  * Revision 2, 2019-06-25 (Matthaeus G. Chajdas)
    - Clarified the meaning of a few fields.
  * Revision 1, 2018-02-15 (Martin Dinkov)
    - Initial draft.