Conformance Test

    GL_ARB_gl_spirv

Contributors

    Adam Czupryna, Mobica

Contacts

    Adam Czupryna, Mobica (adam.czupryna 'at' mobica.com)

Status

    In review

Version

    July 5, 2017 (version 1)

Dependencies

    OpenGL 4.5 is required.

    ARB_gl_spirv extension is required.

    This specification is written against:
    - OpenGL 4.5 Core Profile Specification,
    - version 4.50 (revision 5) Shading Language Specification,
    - ARB_gl_spirv extension Specification.

Overview

    This test verifies two things:

    1. Verifies if OpenGL API allows a SPIR-V module to be specified as containing a
       programmable shader stage, rather than using GLSL, whatever the source language
       was used to create the SPIR-V module.

    2. Verifies if GLSL is modified to be a source language for creating SPIR-V
       modules for OpenGL consumption.

Tests

    SPIR-V Modules Tests

      * Positive Tests

        - Create GLSL shader for each shading stage. Each stage should receive color
          vector from previous stage and multiply it by constant value greater than 1.
          First stage should set color components to non zero values. Last stage should
          draw color to the framebuffer.

          Perform drawing and verify the result. Expect that color read from the
          framebuffer will be correctly multiplied.

        - Use glslang to compile GLSL shaders to SPIR-V binary modules. Create shader
          objects using ShaderBinary function with binary format set to
          SHADER_BINARY_FORMAT_SPIR_V_ARB and specialize it using SpecializeShader
          function.

          Perform drawing and verify the result. Expect the same result as for
          previous case.

      * Shader Binary Multiple Shader Objects

        - Create GLSL shader for at least two shading stages. Use glslang to compile
          GLSL shaders to single SPIR-V module. Create shader object for each stage and
          perform ShaderBinary function passing shader set as an argument, use
          SHADER_BINARY_FORMAT_SPIR_V_ARB binary format. Specialize shader objects
          using SpecializeShader function with proper entry point argument for each
          shader.

          Perform drawing and verify if the result is as expected.

      * State Queries

        - Verify if GetShaderiv with <pname> set to SPIR_V_BINARY_ARB used on valid
          shader created using SHADER_BINARY_FORMAT_SPIR_V_ARB binary format will
          result in TRUE.

        - Verify if ShaderSource function used on shader with SPIR_V_BINARY_ARB state
          set to TRUE will result in changing SPIR_V_BINARY_ARB state to FALSE.

        - Verify if ShaderSource function used on shader with SPIR_V_BINARY_ARB state
          set to TRUE will result in changing SPIR_V_BINARY_ARB state to FALSE.

        - Verify if shader compile status is set to TRUE if shader is specialized.

        - Verify if GetShaderInfoLog function return information about the last
          specialization attempt if SpecializeShader is use in a wrong way.

        - Verify if GetProgramiv function return one for ACTIVE_ATTRIBUTE_MAX_LENGTH
          <pname> when no name reflection information is available.

        - Verify if GetProgramiv function return one for ACTIVE_UNIFORM_MAX_LENGTH
          <pname> when no name reflection information is available.

        - Verify if GetProgramiv function return one for TRANSFORM_FEEDBACK_VARYING_MAX_LENGTH
          <pname> when no name reflection information is available.

        - Verify if GetProgramiv function return one for ACTIVE_UNIFORM_BLOCK_MAX_NAME_LENGTH
          <pname> when no name reflection information is available.

      * Error Verification

        - Verify if CompileShader function used on shader with SPIR_V_BINARY_ARB state
          will result in generating INVALID_OPERATION error.

        - Verify if SpecializeShader function generate INVALID_VALUE error when
          <shader> is not the name of either a program or shader object.

        - Verify if SpecializeShader function generate INVALID_OPERATION error when
          <shader> is the name of a program object.

        - Verify if SpecializeShader function generate INVALID_OPERATION error when
          SPIR_V_BINARY_ARB state for <shader> is not TRUE, or if the shader has
          already been specialized.

        - Verify if SpecializeShader function generate INVALID_VALUE when <pEntryPoint>
          does not name a valid entry point for <shader>.

        - Verify if SpecializeShader function generate INVALID_VALUE when any element
          of <pConstantIndex> refers to a specialization constant that does not exist
          in the shader module contained in <shader>.

        - Verify if LinkProgram fail when one or more of the shader objects attached to
          <program> are not specialized.

        - Verify if LinkProgram fail when not all of shaders attached to <program> have
          the same value for the SPIR_V_BINARY_ARB state.

    GLSL to SPIR-V Features Tests

      * Enable SPIR-V Features

        - Create vertex shader that checks if GL_SPIRV is defined and returns error
          message if not.

      * Built-in Functions

        - Create set of shaders that uses built-in functions listed in section 8 of
          The OpenGL Shading Language 4.50 specification. Compile shader to SPIR-V
          binary module using glslang and disassembly module.

        - Verify if no error occured during compilation.

        - Verify if built-in functions are converted from GLSL to SPIR-V as expected.

        NOTE: noise* built-in functions are excluded from testing as they are deprecated.

      * Specialization Constants

        - Create fragment shader with specialized constant floats - one for each color
          component and forward it to default fragment output as vec4. Compile shader
          to SPIR-V binary module using glslang. Create shader object and specialize it
          with different values.

        - Render a fullscreen polygon and read back pixels from framebuffer.

        - Expect that color components of read pixels follows values used in shader
          specialization.

    SPIR-V Validation

      * SPIR-V Built-In Variable Decorations

        Create SPIR-V modules set that uses built-in variable decorations listed below:

        Built-in Variable Decoration    Minimum GL version (Extension)
        ----------------------------    -----------------------------
        NumWorkgroups                   GL 4.3 (ARB_compute_shader)
        WorkgroupSize                   GL 4.3 (ARB_compute_shader)
        WorkgroupId                     GL 4.3 (ARB_compute_shader)
        LocalInvocationId               GL 4.3 (ARB_compute_shader)
        GlobalInvocationId              GL 4.3 (ARB_compute_shader)
        LocalInvocationIndex            GL 4.3 (ARB_compute_shader)
        VertexId
        InstanceId
        Position
        PointSize
        ClipDistance
        CullDistance                    GL 4.5 (ARB_cull_distance)
        PrimitiveId
        InvocationId                    GL 4.0 (ARB_tessellation_shader)
        Layer
        ViewportIndex                   GL 4.1 (ARB_viewport_array)
        PatchVertices                   GL 4.0 (ARB_tessellation_shader)
        TessLevelOuter                  GL 4.0 (ARB_tessellation_shader)
        TessLevelInner                  GL 4.0 (ARB_tessellation_shader)
        TessCoord                       GL 4.0 (ARB_tessellation_shader)
        FragCoord
        FrontFacing
        PointCoord
        SampleId                        GL 4.0 (ARB_sample_shading)
        SamplePosition                  GL 4.0 (ARB_sample_shading)
        SampleMask                      GL 4.0 (ARB_sample_shading)
        HelperInvocation                GL 4.5 (ARB_ES3_1_compatibility)

        Use SPIR-V modules in apropriate shader stage (adequate to variable it tests).
          Create program objects and execute them. Make sure that no error occured and
          the result of program execution is as expected.

      * SPIR-V Capabilities

        Create SPIR-V modules set that capabilities listed below:

        OpCapability                        Minimum GL version (Extension)
        ------------------------------      -----------------------------
        Matrix
        Shader
        Geometry
        Tessellation                        GL 4.0 (ARB_tessellation_shader)
        Float64                             GL 4.0 (ARB_gpu_shader_fp64)
        AtomicStorage                       GL 4.2 (ARB_shader_atomic_counters)
        TessellationPointSize               GL 4.0 (ARB_tessellation_shader)
        GeometryPointSize
        ImageGatherExtended                 GL 4.0 (ARB_gpu_shader5)
        StorageImageMultisample             GL 4.2 (ARB_shader_image_load_store)
        UniformBufferArrayDynamicIndexing   GL 4.0 (ARB_gpu_shader5)
        SampledImageArrayDynamicIndexing    GL 4.0 (ARB_gpu_shader5)
        StorageBufferArrayDynamicIndexing   GL 4.3 (ARB_shader_storage_buffer_object)
        StorageImageArrayDynamicIndexing    GL 4.2 (ARB_shader_image_load_store)
        ClipDistance
        CullDistance                        GL 4.5 (ARB_cull_distance)
        ImageCubeArray                      GL 4.0 (ARB_texture_cube_map_array)
        SampleRateShading                   GL 4.0 (ARB_sample_shading)
        ImageRect
        SampledRect
        Sampled1D
        Image1D
        SampledCubeArray                    GL 4.0 (ARB_texture_cube_map_array)
        SampledBuffer
        ImageBuffer
        ImageMSArray
        StorageImageExtendedFormats         GL 4.2 (ARB_shader_image_load_store)
        ImageQuery
        DerivativeControl                   GL 4.5 (ARB_derivative_control)
        InterpolationFunction               GL 4.0 (ARB_gpu_shader5)
        TransformFeedback
        GeometryStreams                     GL 4.0 (ARB_gpu_shader5)
        StorageImageWriteWithoutFormat      GL 4.2 (ARB_shader_image_load_store)
        MultiViewport                       GL 4.1 (ARB_viewport_array)
        Int64                               (ARB_gpu_shader_int64)
        SparseResidency                     (ARB_sparse_texture2)
        MinLod                              (ARB_sparse_texture_clamp)
        StorageImageReadWithoutFormat       (EXT_shader_image_load_formatted)
        Int64Atomics                        (NV_shader_atomic_int64)

        Use SPIR-V modules in apropriate shader stage (adequate to capability it tests).
          Create program objects and execute them. Make sure that no error occured and
          the result of program execution is as expected.

Revision History

    Revision 1, 5 July, 2017 (Adam Czupryna)
     - Initial version.