VkShaderStatisticsInfoAMD

The VkShaderStatisticsInfoAMD structure is defined as:

typedef struct VkShaderStatisticsInfoAMD {
    VkShaderStageFlags shaderStageMask;
    VkShaderResourceUsageAMD resourceUsage;
    uint32_t numPhysicalVgprs;
    uint32_t numPhysicalSgprs;
    uint32_t numAvailableVgprs;
    uint32_t numAvailableSgprs;
    uint32_t computeWorkGroupSize[3];
} VkShaderStatisticsInfoAMD;

• shaderStageMask are the combination of logical shader stages contained within this shader.
• resourceUsage is a VkShaderResourceUsageAMD structure describing internal physical device resources used by this shader.
• numPhysicalVgprs is the maximum number of vector instruction general-purpose registers (VGPRs) available to the physical device.
• numPhysicalSgprs is the maximum number of scalar instruction general-purpose registers (SGPRs) available to the physical device.
• numAvailableVgprs is the maximum limit of VGPRs made available to the shader compiler.
• numAvailableSgprs is the maximum limit of SGPRs made available to the shader compiler.
• computeWorkGroupSize is the local workgroup size of this shader in { X, Y, Z } dimensions.

Some implementations may merge multiple logical shader stages together in a single shader. In such cases, shaderStageMask will contain a bitmask of all of the stages that are active within that shader. Consequently, if specifying those stages as input to vkGetShaderInfoAMD, the same output information may be returned for all such shader stage queries.

The number of available VGPRs and SGPRs (numAvailableVgprs and numAvailableSgprs respectively) are the shader-addressable subset of physical registers that is given as a limit to the compiler for register assignment. These values may further be limited by implementations due to performance optimizations where register pressure is a bottleneck.