//
// Copyright 2017 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// AtomicCounterBufferTest:
//   Various tests related for atomic counter buffers.
//

#include "test_utils/ANGLETest.h"
#include "test_utils/gl_raii.h"

using namespace angle;

namespace
{

class AtomicCounterBufferTest : public ANGLETest<>
{
  protected:
    AtomicCounterBufferTest()
    {
        setWindowWidth(128);
        setWindowHeight(128);
        setConfigRedBits(8);
        setConfigGreenBits(8);
        setConfigBlueBits(8);
        setConfigAlphaBits(8);
    }
};

// Test GL_ATOMIC_COUNTER_BUFFER is not supported with version lower than ES31.
TEST_P(AtomicCounterBufferTest, AtomicCounterBufferBindings)
{
    ASSERT_EQ(3, getClientMajorVersion());
    GLBuffer atomicCounterBuffer;
    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicCounterBuffer.get());
    if (getClientMinorVersion() < 1)
    {
        EXPECT_GL_ERROR(GL_INVALID_ENUM);
    }
    else
    {
        EXPECT_GL_NO_ERROR();
    }
}

class AtomicCounterBufferTest31 : public AtomicCounterBufferTest
{};

// Linking should fail if counters in vertex shader exceed gl_MaxVertexAtomicCounters.
TEST_P(AtomicCounterBufferTest31, ExceedMaxVertexAtomicCounters)
{
    constexpr char kVS[] =
        "#version 310 es\n"
        "layout(binding = 0) uniform atomic_uint foo[gl_MaxVertexAtomicCounters + 1];\n"
        "void main()\n"
        "{\n"
        "    atomicCounterIncrement(foo[0]);\n"
        "}\n";
    constexpr char kFS[] =
        "#version 310 es\n"
        "void main()\n"
        "{\n"
        "}\n";

    GLuint program = CompileProgram(kVS, kFS);
    EXPECT_EQ(0u, program);
}

// Test that Tessellation Control Shader Can Read/Write to atomic counter buffers
TEST_P(AtomicCounterBufferTest31, TessellationControlShaderMaxAtomicCounterTests)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_EXT_tessellation_shader"));
    GLint maxTessellationControlAtomicCounters = 0;
    glGetIntegerv(GL_MAX_TESS_CONTROL_ATOMIC_COUNTERS, &maxTessellationControlAtomicCounters);
    ANGLE_SKIP_TEST_IF(maxTessellationControlAtomicCounters <= 0);

    // Cap the atomic counters to an arbitrary value 16 in case we do not have a limit for
    // GL_MAX_TESS_CONTROL_ATOMIC_COUNTERS on certain devices
    GLint maxTessellationControlAtomicCountersCap = 16u;
    maxTessellationControlAtomicCounters =
        std::min(maxTessellationControlAtomicCounters, maxTessellationControlAtomicCountersCap);

    const unsigned int tessellationControlPointsCount = 3;

    // Vertex Shader Code
    const char *kVS =
        "#version 310 es\n"
        "\n"
        "in vec4 a_position;\n"
        "flat out int vertex_id;\n"
        "\n"
        "void main()\n"
        "{\n"
        "    gl_Position  = a_position;\n"
        "}\n";

    // Tessellation Control Shader Code
    // gl_InvocationID = 0: increment all elements in atomic counters acs[].
    // gl_InvocationID = 1: increment acs[index] where index==0
    // gl_InvocationID = 2: increment acs[index] where index==0,1
    // We have tessellationControlPointsCount=3 vertices output from the Tessellation Control
    // Shader Stage, meaning we have three tessellation shader code running in parallel, each with a
    // unique gl_InvocationID.
    std::stringstream tcs_code_sstream;
    tcs_code_sstream
        << "#version 310 es\n"
           "#extension GL_EXT_tessellation_shader : require\n"
           "layout(vertices ="
        << tessellationControlPointsCount
        << ") out;\n"
           "uniform int nLoopIterations;\n"
           "layout(binding = 0) uniform atomic_uint acs["
        << maxTessellationControlAtomicCounters
        << "];\n"
           "void main()\n"
           "{\n"
           "for (int counter_id = 1;\n"
           "counter_id <= nLoopIterations;\n"
           "++counter_id)\n"
           "{\n"
           "if ((gl_InvocationID % counter_id) == 0)\n"
           "{\n"
           "   atomicCounterIncrement(acs[counter_id - 1]);\n"
           "}\n"
           "}\n"
           "\n"
           "       gl_out [gl_InvocationID].gl_Position = gl_in[gl_InvocationID].gl_Position;\n"
           "       gl_TessLevelInner[0] = 1.0;\n"
           "       gl_TessLevelOuter[0] = 1.0;\n"
           "       gl_TessLevelOuter[1] = 1.0;\n"
           "       gl_TessLevelOuter[2] = 1.0;\n"
           "}\n";
    std::string tcs_code = tcs_code_sstream.str();
    const char *kTC      = tcs_code.c_str();

    // Tessellation Evaluation Shader Code
    constexpr char kTES[] =
        "#version 310 es\n"
        "#extension GL_EXT_tessellation_shader : require\n"
        "layout (triangles) in;\n"
        "void main()\n"
        "{\n"
        "   gl_Position = gl_TessCoord[0] * gl_in[0].gl_Position +"
        "                 gl_TessCoord[1] * gl_in[1].gl_Position +"
        "                 gl_TessCoord[2] * gl_in[2].gl_Position;\n"
        "}\n";

    // Fragment Shader Code
    const char *kFS =
        "#version 310 es\n"
        "\n"
        "precision highp float;\n"
        "\n"
        "out vec4 result;\n"
        "\n"
        "void main()\n"
        "{\n"
        "    result = vec4(1.0);\n"
        "}\n";
    GLuint program = CompileProgramWithTESS(kVS, kTC, kTES, kFS);
    EXPECT_NE(0u, program);
    glUseProgram(program);

    // Create and Bind Atomic Counter Buffer Object
    GLuint atomicBufferID;
    glGenBuffers(1, &atomicBufferID);
    GLuint *atomicBufferData = new GLuint[maxTessellationControlAtomicCounters];
    memset(atomicBufferData, 0, sizeof(GLuint) * maxTessellationControlAtomicCounters);
    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicBufferID);
    glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(GLuint) * maxTessellationControlAtomicCounters,
                 NULL, GL_DYNAMIC_COPY);
    glBufferSubData(GL_ATOMIC_COUNTER_BUFFER, 0,
                    sizeof(GLuint) * maxTessellationControlAtomicCounters, atomicBufferData);
    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicBufferID);

    // Bind nLoopIterationsUniformLocation uniform
    GLint nLoopIterationsUniformLocation = -1;
    nLoopIterationsUniformLocation       = glGetUniformLocation(program, "nLoopIterations");
    EXPECT_NE(-1, nLoopIterationsUniformLocation);
    glUniform1i(nLoopIterationsUniformLocation, maxTessellationControlAtomicCounters);

    // Issue a Drawcall
    std::array<Vector3, 3> triangleVertices = {
        Vector3(-1.0f, 1.0f, 0.5f), Vector3(-1.0f, -1.0f, 0.5f), Vector3(1.0f, -1.0f, 0.5f)};
    GLint positionLocation = glGetAttribLocation(program, "a_position");
    glVertexAttribPointer(positionLocation, 3, GL_FLOAT, GL_FALSE, 0, triangleVertices.data());
    glEnableVertexAttribArray(positionLocation);
    glDrawArrays(GL_PATCHES, 0, 3);
    ASSERT_GL_NO_ERROR();

    // Check the value of atomic counter buffer
    GLuint *atomicBufferResult = (GLuint *)glMapBufferRange(
        GL_ATOMIC_COUNTER_BUFFER, 0, sizeof(GLuint) * maxTessellationControlAtomicCounters,
        GL_MAP_READ_BIT);

    for (GLint n_ac = 1; n_ac <= maxTessellationControlAtomicCounters; ++n_ac)
    {
        unsigned int expected_value = 0;
        for (unsigned int n_draw_call_vertex = 0;
             n_draw_call_vertex < tessellationControlPointsCount; ++n_draw_call_vertex)
        {
            if ((n_draw_call_vertex % n_ac) == 0)
            {
                expected_value++;
            }
        }
        EXPECT_EQ(atomicBufferResult[n_ac - 1], expected_value);
    }

    glUnmapBuffer(GL_ATOMIC_COUNTER_BUFFER);
    glDisableVertexAttribArray(positionLocation);
    glDeleteBuffers(1, &atomicBufferID);
    glDeleteProgram(program);
}

// Test that Tessellation Evaluation Shader Can Read/Write to atomic counter buffers
TEST_P(AtomicCounterBufferTest31, TessellationEvaluationShaderMaxAtomicCounterTests)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_EXT_tessellation_shader"));
    GLint maxTessellationEvaluationAtomicCounters = 0;
    glGetIntegerv(GL_MAX_TESS_EVALUATION_ATOMIC_COUNTERS, &maxTessellationEvaluationAtomicCounters);
    ANGLE_SKIP_TEST_IF(maxTessellationEvaluationAtomicCounters <= 0);

    // Cap the atomic counters to an arbitrary value 16 in case we do not have a limit for
    // GL_MAX_TESS_CONTROL_ATOMIC_COUNTERS on certain devices
    GLint maxTessellationEvaluationAtomicCountersCap = 16u;
    maxTessellationEvaluationAtomicCounters = std::min(maxTessellationEvaluationAtomicCounters,
                                                       maxTessellationEvaluationAtomicCountersCap);

    const unsigned int tessellationControlPointsCount = 3;

    // Vertex Shader Code
    const char *kVS =
        "#version 310 es\n"
        "\n"
        "in vec4 a_position;\n"
        "\n"
        "void main()\n"
        "{\n"
        "    gl_Position  = a_position;\n"
        "}\n";

    // Tessellation Control Shader Code
    std::stringstream tcs_code_sstream;
    tcs_code_sstream
        << "#version 310 es\n"
           "#extension GL_EXT_tessellation_shader : require\n"
           "layout(vertices = "
        << tessellationControlPointsCount
        << ") out;\n"
           "void main()\n"
           "{\n"
           "       gl_out[gl_InvocationID].gl_Position = gl_in[gl_InvocationID].gl_Position;\n"
           "       gl_TessLevelInner[0] = 1.0;\n"
           "       gl_TessLevelOuter[0] = 1.0;\n"
           "       gl_TessLevelOuter[1] = 1.0;\n"
           "       gl_TessLevelOuter[2] = 1.0;\n"
           "}\n";
    std::string tcs_code = tcs_code_sstream.str();
    const char *kTC      = tcs_code.c_str();

    // Tessellation Evaluation Shader Code
    // The gl_TessLevelInner and gl_TessLevelOuter values in tessellation control shader (tcs) code
    // are set to 1, meaning we do not subdivide the patch and create more vertices. The number of
    // tessellation evaluation shader (tes) invocations is the same as number of vertex output from
    // tcs (e.g. tessellationControlPointsCount).
    // Increment all elements in atomic counters acs[] in every tes invocation.
    // Final value in atomic counters acs[] should be the same as the number of
    // tes invocations (e.g. tessellationControlPointsCount).
    std::stringstream tes_code_sstream;
    tes_code_sstream << "#version 310 es\n"
                        "#extension GL_EXT_tessellation_shader : require\n"
                        "layout (triangles) in;\n"
                        "uniform int nLoopIterations;\n"
                        "layout(binding = 0) uniform atomic_uint acs["
                     << maxTessellationEvaluationAtomicCounters
                     << "];\n"
                        "void main()\n"
                        "{\n"
                        "for (int counter_id = 0;\n"
                        "counter_id < nLoopIterations;\n"
                        "++counter_id)\n"
                        "{\n"
                        "   atomicCounterIncrement(acs[counter_id]);\n"
                        "}\n"
                        "\n"
                        "   gl_Position = gl_TessCoord[0] * gl_in[0].gl_Position +"
                        "                 gl_TessCoord[1] * gl_in[1].gl_Position +"
                        "                 gl_TessCoord[2] * gl_in[2].gl_Position;\n"
                        "}\n";
    std::string tes_code = tes_code_sstream.str();
    const char *kTES     = tes_code.c_str();

    // Fragment Shader Code
    const char *kFS =
        "#version 310 es\n"
        "\n"
        "precision highp float;\n"
        "\n"
        "out vec4 result;\n"
        "\n"
        "void main()\n"
        "{\n"
        "    result = vec4(1.0);\n"
        "}\n";
    GLuint program = CompileProgramWithTESS(kVS, kTC, kTES, kFS);
    EXPECT_NE(0u, program);
    glUseProgram(program);

    // Create and Bind Atomic Counter Buffer Object
    GLuint atomicBufferID;
    glGenBuffers(1, &atomicBufferID);
    GLuint *atomicBufferData = new GLuint[maxTessellationEvaluationAtomicCounters];
    memset(atomicBufferData, 0, sizeof(GLuint) * maxTessellationEvaluationAtomicCounters);
    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicBufferID);
    glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(GLuint) * maxTessellationEvaluationAtomicCounters,
                 NULL, GL_DYNAMIC_COPY);
    glBufferSubData(GL_ATOMIC_COUNTER_BUFFER, 0,
                    sizeof(GLuint) * maxTessellationEvaluationAtomicCounters, atomicBufferData);
    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicBufferID);

    // Bind nLoopIterationsUniformLocation uniform
    GLint nLoopIterationsUniformLocation = -1;
    nLoopIterationsUniformLocation       = glGetUniformLocation(program, "nLoopIterations");
    EXPECT_NE(-1, nLoopIterationsUniformLocation);
    glUniform1i(nLoopIterationsUniformLocation, maxTessellationEvaluationAtomicCounters);

    // Issue Drawcall
    std::array<Vector3, 3> triangleVertices = {
        Vector3(-1.0f, 1.0f, 0.5f), Vector3(-1.0f, -1.0f, 0.5f), Vector3(1.0f, -1.0f, 0.5f)};
    GLint positionLocation = glGetAttribLocation(program, "a_position");
    glVertexAttribPointer(positionLocation, 3, GL_FLOAT, GL_FALSE, 0, triangleVertices.data());
    glEnableVertexAttribArray(positionLocation);
    glDrawArrays(GL_PATCHES, 0, 3);
    ASSERT_GL_NO_ERROR();

    // Check the value of atomic counter buffer
    GLuint *atomicBufferResult = (GLuint *)glMapBufferRange(
        GL_ATOMIC_COUNTER_BUFFER, 0, sizeof(GLuint) * maxTessellationEvaluationAtomicCounters,
        GL_MAP_READ_BIT);
    unsigned int expected_value = tessellationControlPointsCount;
    for (GLint n_ac = 0; n_ac < maxTessellationEvaluationAtomicCounters; ++n_ac)
    {
        EXPECT_EQ(atomicBufferResult[n_ac], expected_value);
    }

    glUnmapBuffer(GL_ATOMIC_COUNTER_BUFFER);
    glDisableVertexAttribArray(positionLocation);
    glDeleteBuffers(1, &atomicBufferID);
    glDeleteProgram(program);
}

// Counters matching across shader stages should fail if offsets aren't all specified.
// GLSL ES Spec 3.10.4, section 9.2.1.
TEST_P(AtomicCounterBufferTest31, OffsetNotAllSpecified)
{
    constexpr char kVS[] =
        "#version 310 es\n"
        "layout(binding = 0, offset = 4) uniform atomic_uint foo;\n"
        "void main()\n"
        "{\n"
        "    atomicCounterIncrement(foo);\n"
        "}\n";
    constexpr char kFS[] =
        "#version 310 es\n"
        "layout(binding = 0) uniform atomic_uint foo;\n"
        "void main()\n"
        "{\n"
        "}\n";

    GLuint program = CompileProgram(kVS, kFS);
    EXPECT_EQ(0u, program);
}

// Counters matching across shader stages should fail if offsets aren't all specified with same
// value.
TEST_P(AtomicCounterBufferTest31, OffsetNotAllSpecifiedWithSameValue)
{
    constexpr char kVS[] =
        "#version 310 es\n"
        "layout(binding = 0, offset = 4) uniform atomic_uint foo;\n"
        "void main()\n"
        "{\n"
        "    atomicCounterIncrement(foo);\n"
        "}\n";
    constexpr char kFS[] =
        "#version 310 es\n"
        "layout(binding = 0, offset = 8) uniform atomic_uint foo;\n"
        "void main()\n"
        "{\n"
        "}\n";

    GLuint program = CompileProgram(kVS, kFS);
    EXPECT_EQ(0u, program);
}

// Tests atomic counter reads using compute shaders. Used as a confidence check for the translator.
TEST_P(AtomicCounterBufferTest31, AtomicCounterReadCompute)
{
    // Skipping due to a bug on the Adreno OpenGLES Android driver.
    // http://anglebug.com/2925
    ANGLE_SKIP_TEST_IF(IsAndroid() && IsAdreno() && IsOpenGLES());

    constexpr char kComputeShaderSource[] = R"(#version 310 es
layout(local_size_x=1, local_size_y=1, local_size_z=1) in;

void atomicCounterInFunction(in atomic_uint counter[3]);

layout(binding = 0, offset = 8) uniform atomic_uint ac[3];

void atomicCounterInFunction(in atomic_uint counter[3])
{
    atomicCounter(counter[0]);
}

void main()
{
    atomicCounterInFunction(ac);
    atomicCounter(ac[gl_LocalInvocationIndex + 1u]);
})";

    ANGLE_GL_COMPUTE_PROGRAM(program, kComputeShaderSource);
    EXPECT_GL_NO_ERROR();
}

// Test atomic counter read.
TEST_P(AtomicCounterBufferTest31, AtomicCounterRead)
{
    // Skipping test while we work on enabling atomic counter buffer support in th D3D renderer.
    // http://anglebug.com/1729
    ANGLE_SKIP_TEST_IF(IsD3D11());

    constexpr char kFS[] =
        "#version 310 es\n"
        "precision highp float;\n"
        "layout(binding = 0, offset = 4) uniform atomic_uint ac;\n"
        "out highp vec4 my_color;\n"
        "void main()\n"
        "{\n"
        "    my_color = vec4(0.0);\n"
        "    uint a1 = atomicCounter(ac);\n"
        "    if (a1 == 3u) my_color = vec4(1.0);\n"
        "}\n";

    ANGLE_GL_PROGRAM(program, essl31_shaders::vs::Simple(), kFS);

    glUseProgram(program.get());

    // The initial value of counter 'ac' is 3u.
    unsigned int bufferData[3] = {11u, 3u, 1u};
    GLBuffer atomicCounterBuffer;
    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer);
    glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(bufferData), bufferData, GL_STATIC_DRAW);

    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicCounterBuffer);

    drawQuad(program.get(), essl31_shaders::PositionAttrib(), 0.0f);
    ASSERT_GL_NO_ERROR();
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::white);
}

// Test a bug in vulkan back-end where recreating the atomic counter storage should trigger state
// update in the context
TEST_P(AtomicCounterBufferTest31, DependentAtomicCounterBufferChange)
{
    // Skipping test while we work on enabling atomic counter buffer support in th D3D renderer.
    // http://anglebug.com/1729
    ANGLE_SKIP_TEST_IF(IsD3D11());

    constexpr char kFS[] =
        "#version 310 es\n"
        "precision highp float;\n"
        "layout(binding = 0, offset = 4) uniform atomic_uint ac;\n"
        "out highp vec4 my_color;\n"
        "void main()\n"
        "{\n"
        "    my_color = vec4(0.0);\n"
        "    uint a1 = atomicCounter(ac);\n"
        "    if (a1 == 3u) my_color = vec4(1.0);\n"
        "    if (a1 == 19u) my_color = vec4(1.0, 0.0, 0.0, 1.0);\n"
        "}\n";

    ANGLE_GL_PROGRAM(program, essl31_shaders::vs::Simple(), kFS);

    glUseProgram(program.get());

    // The initial value of counter 'ac' is 3u.
    unsigned int bufferDataLeft[3] = {11u, 3u, 1u};
    GLBuffer atomicCounterBuffer;
    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer);
    glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(bufferDataLeft), bufferDataLeft, GL_STATIC_DRAW);

    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicCounterBuffer);
    // Draw left quad
    glViewport(0, 0, getWindowWidth() / 2, getWindowHeight());
    drawQuad(program.get(), essl31_shaders::PositionAttrib(), 0.0f);
    // Draw right quad
    unsigned int bufferDataRight[3] = {11u, 19u, 1u};
    glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(bufferDataRight), bufferDataRight,
                 GL_STATIC_DRAW);
    glViewport(getWindowWidth() / 2, 0, getWindowWidth() / 2, getWindowHeight());
    drawQuad(program.get(), essl31_shaders::PositionAttrib(), 0.0f);
    ASSERT_GL_NO_ERROR();
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::white);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 2, 0, GLColor::red);
}

// Updating atomic counter buffer's offsets was optimized based on a count of valid bindings.
// This test will fail if there are bugs in how we count valid bindings.
TEST_P(AtomicCounterBufferTest31, AtomicCounterBufferRangeRead)
{
    // Skipping due to a bug on the Qualcomm driver.
    // http://anglebug.com/3726
    ANGLE_SKIP_TEST_IF(IsNexus5X() && IsOpenGLES());

    // Skipping test while we work on enabling atomic counter buffer support in th D3D renderer.
    // http://anglebug.com/1729
    ANGLE_SKIP_TEST_IF(IsD3D11());

    constexpr char kFS[] =
        "#version 310 es\n"
        "precision highp float;\n"
        "layout(binding = 0, offset = 4) uniform atomic_uint ac;\n"
        "out highp vec4 my_color;\n"
        "void main()\n"
        "{\n"
        "    my_color = vec4(0.0);\n"
        "    uint a1 = atomicCounter(ac);\n"
        "    if (a1 == 3u) my_color = vec4(1.0);\n"
        "}\n";

    ANGLE_GL_PROGRAM(program, essl31_shaders::vs::Simple(), kFS);

    glUseProgram(program.get());

    // The initial value of counter 'ac' is 3u.
    unsigned int bufferData[]     = {0u, 0u, 0u, 0u, 0u, 11u, 3u, 1u};
    constexpr GLintptr kOffset    = 20;
    GLint maxAtomicCounterBuffers = 0;
    GLBuffer atomicCounterBuffer;

    glGetIntegerv(GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS, &maxAtomicCounterBuffers);
    // Repeatedly bind the same buffer (GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS + 1) times
    // A bug in counting valid atomic counter buffers will cause a crash when we
    // exceed GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS
    for (int32_t i = 0; i < maxAtomicCounterBuffers + 1; i++)
    {
        glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer);
        glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(bufferData), bufferData, GL_STATIC_DRAW);
        glBindBufferRange(GL_ATOMIC_COUNTER_BUFFER, 0, atomicCounterBuffer, kOffset,
                          sizeof(bufferData) - kOffset);
    }

    drawQuad(program.get(), essl31_shaders::PositionAttrib(), 0.0f);
    ASSERT_GL_NO_ERROR();
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::white);
}

// Updating atomic counter buffer's offsets was optimized based on a count of valid bindings.
// Repeatedly bind/unbind buffers across available binding points. The test will fail if
// there are bugs in how we count valid bindings.
TEST_P(AtomicCounterBufferTest31, AtomicCounterBufferRepeatedBindUnbind)
{
    // Skipping test while we work on enabling atomic counter buffer support in th D3D renderer.
    // http://anglebug.com/1729
    ANGLE_SKIP_TEST_IF(IsD3D11());

    constexpr char kFS[] =
        "#version 310 es\n"
        "precision highp float;\n"
        "layout(binding = 0, offset = 4) uniform atomic_uint ac;\n"
        "out highp vec4 my_color;\n"
        "void main()\n"
        "{\n"
        "    my_color = vec4(0.0);\n"
        "    uint a1 = atomicCounter(ac);\n"
        "    if (a1 == 3u) my_color = vec4(1.0);\n"
        "}\n";

    ANGLE_GL_PROGRAM(program, essl31_shaders::vs::Simple(), kFS);

    glUseProgram(program.get());

    constexpr int32_t kBufferCount = 16;
    // The initial value of counter 'ac' is 3u.
    unsigned int bufferData[3] = {11u, 3u, 1u};
    GLBuffer atomicCounterBuffer[kBufferCount];
    // Populate atomicCounterBuffer[0] with valid data and the rest with nullptr
    for (int32_t bufferIndex = 0; bufferIndex < kBufferCount; bufferIndex++)
    {
        glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer[bufferIndex]);
        glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(bufferData),
                     (bufferIndex == 0) ? bufferData : nullptr, GL_STATIC_DRAW);
    }

    GLint maxAtomicCounterBuffers = 0;
    glGetIntegerv(GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS, &maxAtomicCounterBuffers);

    // Cycle through multiple buffers
    for (int32_t i = 0; i < kBufferCount; i++)
    {
        constexpr int32_t kBufferIndices[kBufferCount] = {7, 12, 15, 5, 13, 14, 1, 2,
                                                          0, 6,  4,  9, 8,  11, 3, 10};
        int32_t bufferIndex                            = kBufferIndices[i];

        // Randomly bind/unbind buffers to/from different binding points,
        // capped by GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS
        for (int32_t bufferCount = 0; bufferCount < maxAtomicCounterBuffers; bufferCount++)
        {
            constexpr uint32_t kBindingSlotsSize                = kBufferCount;
            constexpr uint32_t kBindingSlots[kBindingSlotsSize] = {1,  3,  4, 14, 15, 9, 0, 6,
                                                                   12, 11, 8, 5,  10, 2, 7, 13};

            uint32_t bindingSlotIndex = bufferCount % kBindingSlotsSize;
            uint32_t bindingSlot      = kBindingSlots[bindingSlotIndex];
            uint32_t bindingPoint     = bindingSlot % maxAtomicCounterBuffers;
            bool even                 = (bufferCount % 2 == 0);
            int32_t bufferId          = (even) ? 0 : atomicCounterBuffer[bufferIndex];

            glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, bindingPoint, bufferId);
        }
    }

    // Bind atomicCounterBuffer[0] to slot 0 and verify result
    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicCounterBuffer[0]);
    drawQuad(program.get(), essl31_shaders::PositionAttrib(), 0.0f);
    ASSERT_GL_NO_ERROR();
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::white);
}

// Test atomic counter increment and decrement.
TEST_P(AtomicCounterBufferTest31, AtomicCounterIncrementAndDecrement)
{
    constexpr char kCS[] =
        "#version 310 es\n"
        "layout(local_size_x=1, local_size_y=1, local_size_z=1) in;\n"
        "layout(binding = 0, offset = 4) uniform atomic_uint ac[2];\n"
        "void main()\n"
        "{\n"
        "    atomicCounterIncrement(ac[0]);\n"
        "    atomicCounterDecrement(ac[1]);\n"
        "}\n";

    ANGLE_GL_COMPUTE_PROGRAM(program, kCS);

    glUseProgram(program.get());

    // The initial value of 'ac[0]' is 3u, 'ac[1]' is 1u.
    unsigned int bufferData[3] = {11u, 3u, 1u};
    GLBuffer atomicCounterBuffer;
    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer);
    glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(bufferData), bufferData, GL_STATIC_DRAW);

    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicCounterBuffer);

    glDispatchCompute(1, 1, 1);
    EXPECT_GL_NO_ERROR();

    glMemoryBarrier(GL_BUFFER_UPDATE_BARRIER_BIT);

    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer);
    void *mappedBuffer =
        glMapBufferRange(GL_ATOMIC_COUNTER_BUFFER, 0, sizeof(GLuint) * 3, GL_MAP_READ_BIT);
    memcpy(bufferData, mappedBuffer, sizeof(bufferData));
    glUnmapBuffer(GL_ATOMIC_COUNTER_BUFFER);

    EXPECT_EQ(11u, bufferData[0]);
    EXPECT_EQ(4u, bufferData[1]);
    EXPECT_EQ(0u, bufferData[2]);
}

// Tests multiple atomic counter buffers.
TEST_P(AtomicCounterBufferTest31, AtomicCounterMultipleBuffers)
{
    GLint maxAtomicCounterBuffers = 0;
    glGetIntegerv(GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS, &maxAtomicCounterBuffers);
    constexpr unsigned int kBufferCount = 3;
    // ES 3.1 table 20.45 only guarantees 1 atomic counter buffer
    ANGLE_SKIP_TEST_IF(maxAtomicCounterBuffers < static_cast<int>(kBufferCount));

    constexpr char kComputeShaderSource[] = R"(#version 310 es
layout(local_size_x=1, local_size_y=1, local_size_z=1) in;
layout(binding = 0) uniform atomic_uint ac1;
layout(binding = 1) uniform atomic_uint ac2;
layout(binding = 2) uniform atomic_uint ac3;

void main()
{
    atomicCounterIncrement(ac1);
    atomicCounterIncrement(ac2);
    atomicCounterIncrement(ac3);
})";

    ANGLE_GL_COMPUTE_PROGRAM(program, kComputeShaderSource);

    glUseProgram(program);

    GLBuffer atomicCounterBuffers[kBufferCount];

    for (unsigned int ii = 0; ii < kBufferCount; ++ii)
    {
        GLuint initialData[1] = {ii};
        glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffers[ii]);
        glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(initialData), initialData, GL_STATIC_DRAW);

        glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, ii, atomicCounterBuffers[ii]);
    }

    glDispatchCompute(1, 1, 1);
    EXPECT_GL_NO_ERROR();

    glMemoryBarrier(GL_BUFFER_UPDATE_BARRIER_BIT);

    for (unsigned int ii = 0; ii < kBufferCount; ++ii)
    {
        glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffers[ii]);
        GLuint *mappedBuffer = static_cast<GLuint *>(
            glMapBufferRange(GL_ATOMIC_COUNTER_BUFFER, 0, sizeof(GLuint), GL_MAP_READ_BIT));
        EXPECT_EQ(ii + 1, mappedBuffer[0]);
        glUnmapBuffer(GL_ATOMIC_COUNTER_BUFFER);
    }
}

// Test atomic counter array of array.
TEST_P(AtomicCounterBufferTest31, AtomicCounterArrayOfArray)
{
    // Fails on D3D.  Some counters are double-incremented while some are untouched, hinting at a
    // bug in index translation.  http://anglebug.com/3783
    ANGLE_SKIP_TEST_IF(IsD3D11());

    // Nvidia's OpenGL driver fails to compile the shader.  http://anglebug.com/3791
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsNVIDIA());

    // Intel's Windows OpenGL driver crashes in this test.  http://anglebug.com/3791
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsWindows());

    constexpr char kCS[] = R"(#version 310 es
layout(local_size_x=1, local_size_y=1, local_size_z=1) in;
layout(binding = 0) uniform atomic_uint ac[7][5][3];

void f0(in atomic_uint ac)
{
    atomicCounterIncrement(ac);
}

void f1(in atomic_uint ac[3])
{
    atomicCounterIncrement(ac[0]);
    f0(ac[1]);
    int index = 2;
    f0(ac[index]);
}

void f2(in atomic_uint ac[5][3])
{
    // Increment all in ac[0], ac[1] and ac[2]
    for (int i = 0; i < 3; ++i)
    {
        for (int j = 0; j < 2; ++j)
        {
            f0(ac[i][j]);
        }
        f0(ac[i][2]);
    }

    // Increment all in ac[3]
    f1(ac[3]);

    // Increment all in ac[4]
    for (int i = 0; i < 2; ++i)
    {
        atomicCounterIncrement(ac[4][i]);
    }
    f0(ac[4][2]);
}

void f3(in atomic_uint ac[7][5][3])
{
    // Increment all in ac[0], ac[1], ac[2] and ac[3]
    f2(ac[0]);
    for (int i = 1; i < 4; ++i)
    {
        f2(ac[i]);
    }

    // Increment all in ac[5][0], ac[5][1], ac[5][2] and ac[5][3]
    for (int i = 0; i < 4; ++i)
    {
        f1(ac[5][i]);
    }

    // Increment all in ac[5][4][0], ac[5][4][1] and ac[5][4][2]
    f0(ac[5][4][0]);
    for (int i = 1; i < 3; ++i)
    {
        f0(ac[5][4][i]);
    }

    // Increment all in ac[6]
    for (int i = 0; i < 5; ++i)
    {
        for (int j = 0; j < 2; ++j)
        {
            atomicCounterIncrement(ac[6][i][j]);
        }
        atomicCounterIncrement(ac[6][i][2]);
    }
}

void main()
{
    // Increment all in ac except ac[4]
    f3(ac);

    // Increment all in ac[4]
    f2(ac[4]);
})";

    constexpr uint32_t kAtomicCounterRows  = 7;
    constexpr uint32_t kAtomicCounterCols  = 5;
    constexpr uint32_t kAtomicCounterDepth = 3;
    constexpr uint32_t kAtomicCounterCount =
        kAtomicCounterRows * kAtomicCounterCols * kAtomicCounterDepth;

    GLint maxAtomicCounters = 0;
    glGetIntegerv(GL_MAX_COMPUTE_ATOMIC_COUNTERS, &maxAtomicCounters);
    EXPECT_GL_NO_ERROR();

    // Required minimum is 8 by the spec
    EXPECT_GE(maxAtomicCounters, 8);
    ANGLE_SKIP_TEST_IF(static_cast<uint32_t>(maxAtomicCounters) < kAtomicCounterCount);

    ANGLE_GL_COMPUTE_PROGRAM(program, kCS);
    glUseProgram(program.get());

    // The initial value of atomic counters is 0, 1, 2, ...
    unsigned int bufferData[kAtomicCounterCount] = {};
    for (uint32_t index = 0; index < kAtomicCounterCount; ++index)
    {
        bufferData[index] = index;
    }

    GLBuffer atomicCounterBuffer;
    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer);
    glBufferData(GL_ATOMIC_COUNTER_BUFFER, sizeof(bufferData), bufferData, GL_STATIC_DRAW);

    glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomicCounterBuffer);

    glDispatchCompute(1, 1, 1);
    EXPECT_GL_NO_ERROR();

    glMemoryBarrier(GL_BUFFER_UPDATE_BARRIER_BIT);

    unsigned int result[kAtomicCounterCount] = {};
    glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomicCounterBuffer);
    void *mappedBuffer =
        glMapBufferRange(GL_ATOMIC_COUNTER_BUFFER, 0, sizeof(bufferData), GL_MAP_READ_BIT);
    memcpy(result, mappedBuffer, sizeof(bufferData));
    glUnmapBuffer(GL_ATOMIC_COUNTER_BUFFER);

    for (uint32_t index = 0; index < kAtomicCounterCount; ++index)
    {
        EXPECT_EQ(result[index], bufferData[index] + 1) << "index " << index;
    }
}

// Test inactive atomic counter
TEST_P(AtomicCounterBufferTest31, AtomicCounterInactive)
{
    constexpr char kFS[] =
        "#version 310 es\n"
        "precision highp float;\n"

        // This inactive atomic counter should be removed by RemoveInactiveInterfaceVariables
        "layout(binding = 0) uniform atomic_uint inactive;\n"

        "out highp vec4 my_color;\n"
        "void main()\n"
        "{\n"
        "    my_color = vec4(0.0, 1.0, 0.0, 1.0);\n"
        "}\n";

    ANGLE_GL_PROGRAM(program, essl31_shaders::vs::Simple(), kFS);
    glUseProgram(program);

    drawQuad(program, essl31_shaders::PositionAttrib(), 0.0f);
    ASSERT_GL_NO_ERROR();

    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);
}

// Test inactive memoryBarrierAtomicCounter
TEST_P(AtomicCounterBufferTest31, AtomicCounterMemoryBarrier)
{
    constexpr char kFS[] =
        "#version 310 es\n"
        "precision highp float;\n"
        // This inactive atomic counter should be removed by RemoveInactiveInterfaceVariables
        "layout(binding = 0) uniform atomic_uint inactive;\n"
        "out highp vec4 my_color;\n"
        "void main()\n"
        "{\n"
        "    my_color = vec4(0.0, 1.0, 0.0, 1.0);\n"
        // This barrier should be removed by RemoveAtomicCounterBuiltins because
        // there are no active atomic counters
        "    memoryBarrierAtomicCounter();\n"
        "}\n";

    ANGLE_GL_PROGRAM(program, essl31_shaders::vs::Simple(), kFS);
    glUseProgram(program);

    drawQuad(program, essl31_shaders::PositionAttrib(), 0.0f);
    ASSERT_GL_NO_ERROR();

    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);
}

GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(AtomicCounterBufferTest);
GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(AtomicCounterBufferTest31);
ANGLE_INSTANTIATE_TEST_ES3_AND_ES31(AtomicCounterBufferTest);
ANGLE_INSTANTIATE_TEST_ES31(AtomicCounterBufferTest31);

}  // namespace
