// Copyright 2019 The Dawn Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "common/Assert.h"
#include "common/Constants.h"
#include "common/Math.h"
#include "tests/DawnTest.h"
#include "utils/ComboRenderPipelineDescriptor.h"
#include "utils/WGPUHelpers.h"

class GpuMemorySyncTests : public DawnTest {
  protected:
    wgpu::Buffer CreateBuffer() {
        wgpu::BufferDescriptor srcDesc;
        srcDesc.size = 4;
        srcDesc.usage =
            wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::Storage;
        wgpu::Buffer buffer = device.CreateBuffer(&srcDesc);

        int myData = 0;
        queue.WriteBuffer(buffer, 0, &myData, sizeof(myData));
        return buffer;
    }

    std::tuple<wgpu::ComputePipeline, wgpu::BindGroup> CreatePipelineAndBindGroupForCompute(
        const wgpu::Buffer& buffer) {
        wgpu::ShaderModule csModule =
            utils::CreateShaderModule(device, utils::SingleShaderStage::Compute, R"(
        #version 450
        layout(std140, set = 0, binding = 0) buffer Data {
            int a;
        } data;
        void main() {
            data.a += 1;
        })");

        wgpu::ComputePipelineDescriptor cpDesc;
        cpDesc.computeStage.module = csModule;
        cpDesc.computeStage.entryPoint = "main";
        wgpu::ComputePipeline pipeline = device.CreateComputePipeline(&cpDesc);

        wgpu::BindGroup bindGroup =
            utils::MakeBindGroup(device, pipeline.GetBindGroupLayout(0), {{0, buffer}});
        return std::make_tuple(pipeline, bindGroup);
    }

    std::tuple<wgpu::RenderPipeline, wgpu::BindGroup> CreatePipelineAndBindGroupForRender(
        const wgpu::Buffer& buffer,
        wgpu::TextureFormat colorFormat) {
        wgpu::ShaderModule vsModule =
            utils::CreateShaderModule(device, utils::SingleShaderStage::Vertex, R"(
        #version 450
        void main() {
            gl_Position = vec4(0.f, 0.f, 0.f, 1.f);
            gl_PointSize = 1.0;
        })");

        wgpu::ShaderModule fsModule =
            utils::CreateShaderModule(device, utils::SingleShaderStage::Fragment, R"(
        #version 450
        layout (set = 0, binding = 0) buffer Data {
            int i;
        } data;
        layout(location = 0) out vec4 fragColor;
        void main() {
            data.i += 1;
            fragColor = vec4(data.i / 255.f, 0.f, 0.f, 1.f);
        })");

        utils::ComboRenderPipelineDescriptor rpDesc(device);
        rpDesc.vertexStage.module = vsModule;
        rpDesc.cFragmentStage.module = fsModule;
        rpDesc.primitiveTopology = wgpu::PrimitiveTopology::PointList;
        rpDesc.cColorStates[0].format = colorFormat;

        wgpu::RenderPipeline pipeline = device.CreateRenderPipeline(&rpDesc);

        wgpu::BindGroup bindGroup =
            utils::MakeBindGroup(device, pipeline.GetBindGroupLayout(0), {{0, buffer}});
        return std::make_tuple(pipeline, bindGroup);
    }
};

// Clear storage buffer with zero. Then read data, add one, and write the result to storage buffer
// in compute pass. Iterate this read-add-write steps per compute pass a few time. The successive
// iteration reads the result in buffer from last iteration, which makes the iterations a data
// dependency chain. The test verifies that data in buffer among iterations in compute passes is
// correctly synchronized.
TEST_P(GpuMemorySyncTests, ComputePass) {
    // Create pipeline, bind group, and buffer for compute pass.
    wgpu::Buffer buffer = CreateBuffer();
    wgpu::ComputePipeline compute;
    wgpu::BindGroup bindGroup;
    std::tie(compute, bindGroup) = CreatePipelineAndBindGroupForCompute(buffer);
    wgpu::CommandEncoder encoder = device.CreateCommandEncoder();

    // Iterate the read-add-write operations in compute pass a few times.
    int iteration = 3;
    for (int i = 0; i < iteration; ++i) {
        wgpu::ComputePassEncoder pass = encoder.BeginComputePass();
        pass.SetPipeline(compute);
        pass.SetBindGroup(0, bindGroup);
        pass.Dispatch(1);
        pass.EndPass();
    }

    wgpu::CommandBuffer commands = encoder.Finish();
    queue.Submit(1, &commands);

    // Verify the result.
    EXPECT_BUFFER_U32_EQ(iteration, buffer, 0);
}

// Clear storage buffer with zero. Then read data, add one, and write the result to storage buffer
// in render pass. Iterate this read-add-write steps per render pass a few time. The successive
// iteration reads the result in buffer from last iteration, which makes the iterations a data
// dependency chain. In addition, color output by fragment shader depends on the data in storage
// buffer, so we can check color in render target to verify that data in buffer among iterations in
// render passes is correctly synchronized.
TEST_P(GpuMemorySyncTests, RenderPass) {
    // Create pipeline, bind group, and buffer for render pass.
    wgpu::Buffer buffer = CreateBuffer();
    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, 1, 1);
    wgpu::RenderPipeline render;
    wgpu::BindGroup bindGroup;
    std::tie(render, bindGroup) =
        CreatePipelineAndBindGroupForRender(buffer, renderPass.colorFormat);
    wgpu::CommandEncoder encoder = device.CreateCommandEncoder();

    // Iterate the read-add-write operations in render pass a few times.
    int iteration = 3;
    for (int i = 0; i < iteration; ++i) {
        wgpu::RenderPassEncoder pass = encoder.BeginRenderPass(&renderPass.renderPassInfo);
        pass.SetPipeline(render);
        pass.SetBindGroup(0, bindGroup);
        pass.Draw(1);
        pass.EndPass();
    }

    wgpu::CommandBuffer commands = encoder.Finish();
    queue.Submit(1, &commands);

    // Verify the result.
    EXPECT_PIXEL_RGBA8_EQ(RGBA8(iteration, 0, 0, 255), renderPass.color, 0, 0);
}

// Write into a storage buffer in a render pass. Then read that data in a compute
// pass. And verify the data flow is correctly synchronized.
TEST_P(GpuMemorySyncTests, RenderPassToComputePass) {
    // Create pipeline, bind group, and buffer for render pass and compute pass.
    wgpu::Buffer buffer = CreateBuffer();
    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, 1, 1);
    wgpu::RenderPipeline render;
    wgpu::BindGroup bindGroup0;
    std::tie(render, bindGroup0) =
        CreatePipelineAndBindGroupForRender(buffer, renderPass.colorFormat);

    wgpu::ComputePipeline compute;
    wgpu::BindGroup bindGroup1;
    std::tie(compute, bindGroup1) = CreatePipelineAndBindGroupForCompute(buffer);

    wgpu::CommandEncoder encoder = device.CreateCommandEncoder();

    // Write data into a storage buffer in render pass.
    wgpu::RenderPassEncoder pass0 = encoder.BeginRenderPass(&renderPass.renderPassInfo);
    pass0.SetPipeline(render);
    pass0.SetBindGroup(0, bindGroup0);
    pass0.Draw(1);
    pass0.EndPass();

    // Read that data in compute pass.
    wgpu::ComputePassEncoder pass1 = encoder.BeginComputePass();
    pass1.SetPipeline(compute);
    pass1.SetBindGroup(0, bindGroup1);
    pass1.Dispatch(1);
    pass1.EndPass();

    wgpu::CommandBuffer commands = encoder.Finish();
    queue.Submit(1, &commands);

    // Verify the result.
    EXPECT_BUFFER_U32_EQ(2, buffer, 0);
}

// Write into a storage buffer in a compute pass. Then read that data in a render
// pass. And verify the data flow is correctly synchronized.
TEST_P(GpuMemorySyncTests, ComputePassToRenderPass) {
    // Create pipeline, bind group, and buffer for compute pass and render pass.
    wgpu::Buffer buffer = CreateBuffer();
    wgpu::ComputePipeline compute;
    wgpu::BindGroup bindGroup1;
    std::tie(compute, bindGroup1) = CreatePipelineAndBindGroupForCompute(buffer);

    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, 1, 1);
    wgpu::RenderPipeline render;
    wgpu::BindGroup bindGroup0;
    std::tie(render, bindGroup0) =
        CreatePipelineAndBindGroupForRender(buffer, renderPass.colorFormat);

    wgpu::CommandEncoder encoder = device.CreateCommandEncoder();

    // Write data into a storage buffer in compute pass.
    wgpu::ComputePassEncoder pass0 = encoder.BeginComputePass();
    pass0.SetPipeline(compute);
    pass0.SetBindGroup(0, bindGroup1);
    pass0.Dispatch(1);
    pass0.EndPass();

    // Read that data in render pass.
    wgpu::RenderPassEncoder pass1 = encoder.BeginRenderPass(&renderPass.renderPassInfo);
    pass1.SetPipeline(render);
    pass1.SetBindGroup(0, bindGroup0);
    pass1.Draw(1);
    pass1.EndPass();

    wgpu::CommandBuffer commands = encoder.Finish();
    queue.Submit(1, &commands);

    // Verify the result.
    EXPECT_PIXEL_RGBA8_EQ(RGBA8(2, 0, 0, 255), renderPass.color, 0, 0);
}

DAWN_INSTANTIATE_TEST(GpuMemorySyncTests,
                      D3D12Backend(),
                      MetalBackend(),
                      OpenGLBackend(),
                      VulkanBackend());

class StorageToUniformSyncTests : public DawnTest {
  protected:
    void CreateBuffer() {
        wgpu::BufferDescriptor bufferDesc;
        bufferDesc.size = sizeof(float);
        bufferDesc.usage = wgpu::BufferUsage::Storage | wgpu::BufferUsage::Uniform;
        mBuffer = device.CreateBuffer(&bufferDesc);
    }

    std::tuple<wgpu::ComputePipeline, wgpu::BindGroup> CreatePipelineAndBindGroupForCompute() {
        wgpu::ShaderModule csModule =
            utils::CreateShaderModule(device, utils::SingleShaderStage::Compute, R"(
        #version 450
        layout(std140, set = 0, binding = 0) buffer Data {
            float a;
        } data;
        void main() {
            data.a = 1.0;
        })");

        wgpu::ComputePipelineDescriptor cpDesc;
        cpDesc.computeStage.module = csModule;
        cpDesc.computeStage.entryPoint = "main";
        wgpu::ComputePipeline pipeline = device.CreateComputePipeline(&cpDesc);

        wgpu::BindGroup bindGroup =
            utils::MakeBindGroup(device, pipeline.GetBindGroupLayout(0), {{0, mBuffer}});
        return std::make_tuple(pipeline, bindGroup);
    }

    std::tuple<wgpu::RenderPipeline, wgpu::BindGroup> CreatePipelineAndBindGroupForRender(
        wgpu::TextureFormat colorFormat) {
        wgpu::ShaderModule vsModule =
            utils::CreateShaderModule(device, utils::SingleShaderStage::Vertex, R"(
        #version 450
        void main() {
            gl_Position = vec4(0.f, 0.f, 0.f, 1.f);
            gl_PointSize = 1.0;
        })");

        wgpu::ShaderModule fsModule =
            utils::CreateShaderModule(device, utils::SingleShaderStage::Fragment, R"(
        #version 450
        layout (set = 0, binding = 0) uniform Contents{
            float color;
        };
        layout(location = 0) out vec4 fragColor;
        void main() {
            fragColor = vec4(color, 0.f, 0.f, 1.f);
        })");

        utils::ComboRenderPipelineDescriptor rpDesc(device);
        rpDesc.vertexStage.module = vsModule;
        rpDesc.cFragmentStage.module = fsModule;
        rpDesc.primitiveTopology = wgpu::PrimitiveTopology::PointList;
        rpDesc.cColorStates[0].format = colorFormat;

        wgpu::RenderPipeline pipeline = device.CreateRenderPipeline(&rpDesc);

        wgpu::BindGroup bindGroup =
            utils::MakeBindGroup(device, pipeline.GetBindGroupLayout(0), {{0, mBuffer}});
        return std::make_tuple(pipeline, bindGroup);
    }

    wgpu::Buffer mBuffer;
};

// Write into a storage buffer in compute pass in a command buffer. Then read that data in a render
// pass. The two passes use the same command buffer.
TEST_P(StorageToUniformSyncTests, ReadAfterWriteWithSameCommandBuffer) {
    // Create pipeline, bind group, and buffer for compute pass and render pass.
    CreateBuffer();
    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, 1, 1);
    wgpu::ComputePipeline compute;
    wgpu::BindGroup computeBindGroup;
    std::tie(compute, computeBindGroup) = CreatePipelineAndBindGroupForCompute();
    wgpu::RenderPipeline render;
    wgpu::BindGroup renderBindGroup;
    std::tie(render, renderBindGroup) = CreatePipelineAndBindGroupForRender(renderPass.colorFormat);

    // Write data into a storage buffer in compute pass.
    wgpu::CommandEncoder encoder0 = device.CreateCommandEncoder();
    wgpu::ComputePassEncoder pass0 = encoder0.BeginComputePass();
    pass0.SetPipeline(compute);
    pass0.SetBindGroup(0, computeBindGroup);
    pass0.Dispatch(1);
    pass0.EndPass();

    // Read that data in render pass.
    wgpu::RenderPassEncoder pass1 = encoder0.BeginRenderPass(&renderPass.renderPassInfo);
    pass1.SetPipeline(render);
    pass1.SetBindGroup(0, renderBindGroup);
    pass1.Draw(1);
    pass1.EndPass();

    wgpu::CommandBuffer commands = encoder0.Finish();
    queue.Submit(1, &commands);

    // Verify the rendering result.
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kRed, renderPass.color, 0, 0);
}

// Write into a storage buffer in compute pass in a command buffer. Then read that data in a render
// pass. The two passes use the different command buffers. The command buffers are submitted to the
// queue in one shot.
TEST_P(StorageToUniformSyncTests, ReadAfterWriteWithDifferentCommandBuffers) {
    // Create pipeline, bind group, and buffer for compute pass and render pass.
    CreateBuffer();
    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, 1, 1);
    wgpu::ComputePipeline compute;
    wgpu::BindGroup computeBindGroup;
    std::tie(compute, computeBindGroup) = CreatePipelineAndBindGroupForCompute();
    wgpu::RenderPipeline render;
    wgpu::BindGroup renderBindGroup;
    std::tie(render, renderBindGroup) = CreatePipelineAndBindGroupForRender(renderPass.colorFormat);

    // Write data into a storage buffer in compute pass.
    wgpu::CommandBuffer cb[2];
    wgpu::CommandEncoder encoder0 = device.CreateCommandEncoder();
    wgpu::ComputePassEncoder pass0 = encoder0.BeginComputePass();
    pass0.SetPipeline(compute);
    pass0.SetBindGroup(0, computeBindGroup);
    pass0.Dispatch(1);
    pass0.EndPass();
    cb[0] = encoder0.Finish();

    // Read that data in render pass.
    wgpu::CommandEncoder encoder1 = device.CreateCommandEncoder();
    wgpu::RenderPassEncoder pass1 = encoder1.BeginRenderPass(&renderPass.renderPassInfo);
    pass1.SetPipeline(render);
    pass1.SetBindGroup(0, renderBindGroup);
    pass1.Draw(1);
    pass1.EndPass();

    cb[1] = encoder1.Finish();
    queue.Submit(2, cb);

    // Verify the rendering result.
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kRed, renderPass.color, 0, 0);
}

// Write into a storage buffer in compute pass in a command buffer. Then read that data in a render
// pass. The two passes use the different command buffers. The command buffers are submitted to the
// queue separately.
TEST_P(StorageToUniformSyncTests, ReadAfterWriteWithDifferentQueueSubmits) {
    // Create pipeline, bind group, and buffer for compute pass and render pass.
    CreateBuffer();
    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, 1, 1);
    wgpu::ComputePipeline compute;
    wgpu::BindGroup computeBindGroup;
    std::tie(compute, computeBindGroup) = CreatePipelineAndBindGroupForCompute();
    wgpu::RenderPipeline render;
    wgpu::BindGroup renderBindGroup;
    std::tie(render, renderBindGroup) = CreatePipelineAndBindGroupForRender(renderPass.colorFormat);

    // Write data into a storage buffer in compute pass.
    wgpu::CommandBuffer cb[2];
    wgpu::CommandEncoder encoder0 = device.CreateCommandEncoder();
    wgpu::ComputePassEncoder pass0 = encoder0.BeginComputePass();
    pass0.SetPipeline(compute);
    pass0.SetBindGroup(0, computeBindGroup);
    pass0.Dispatch(1);
    pass0.EndPass();
    cb[0] = encoder0.Finish();
    queue.Submit(1, &cb[0]);

    // Read that data in render pass.
    wgpu::CommandEncoder encoder1 = device.CreateCommandEncoder();
    wgpu::RenderPassEncoder pass1 = encoder1.BeginRenderPass(&renderPass.renderPassInfo);
    pass1.SetPipeline(render);
    pass1.SetBindGroup(0, renderBindGroup);
    pass1.Draw(1);
    pass1.EndPass();

    cb[1] = encoder1.Finish();
    queue.Submit(1, &cb[1]);

    // Verify the rendering result.
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kRed, renderPass.color, 0, 0);
}

DAWN_INSTANTIATE_TEST(StorageToUniformSyncTests,
                      D3D12Backend(),
                      MetalBackend(),
                      OpenGLBackend(),
                      VulkanBackend());

constexpr int kRTSize = 8;
constexpr int kVertexBufferStride = 4 * sizeof(float);

class MultipleWriteThenMultipleReadTests : public DawnTest {
  protected:
    wgpu::Buffer CreateZeroedBuffer(uint64_t size, wgpu::BufferUsage usage) {
        wgpu::BufferDescriptor srcDesc;
        srcDesc.size = size;
        srcDesc.usage = usage;
        wgpu::Buffer buffer = device.CreateBuffer(&srcDesc);

        std::vector<uint8_t> zeros(size, 0);
        queue.WriteBuffer(buffer, 0, zeros.data(), size);

        return buffer;
    }
};

// Write into a few storage buffers in compute pass. Then read that data in a render pass. The
// readonly buffers in render pass include vertex buffer, index buffer, uniform buffer, and readonly
// storage buffer. Data to be read in all of these buffers in render pass depend on the write
// operation in compute pass.
TEST_P(MultipleWriteThenMultipleReadTests, SeparateBuffers) {
    // Create pipeline, bind group, and different buffers for compute pass.
    wgpu::ShaderModule csModule =
        utils::CreateShaderModule(device, utils::SingleShaderStage::Compute, R"(
        #version 450
        layout(std140, set = 0, binding = 0) buffer VBContents {
            vec4 pos[4];
        };

        layout(std140, set = 0, binding = 1) buffer IBContents {
            ivec4 indices[2];
        };

        layout(std140, set = 0, binding = 2) buffer UniformContents {
            float color0;
        };

        layout(std140, set = 0, binding = 3) buffer ReadonlyStorageContents {
            float color1;
        };

        void main() {
            pos[0] = vec4(-1.f, 1.f, 0.f, 1.f);
            pos[1] = vec4(1.f, 1.f, 0.f, 1.f);
            pos[2] = vec4(1.f, -1.f, 0.f, 1.f);
            pos[3] = vec4(-1.f, -1.f, 0.f, 1.f);
            int dummy = 0;
            indices[0] = ivec4(0, 1, 2, 0);
            indices[1] = ivec4(2, 3, dummy, dummy);
            color0 = 1.0;
            color1 = 1.0;
        })");

    wgpu::ComputePipelineDescriptor cpDesc;
    cpDesc.computeStage.module = csModule;
    cpDesc.computeStage.entryPoint = "main";
    wgpu::ComputePipeline cp = device.CreateComputePipeline(&cpDesc);
    wgpu::Buffer vertexBuffer = CreateZeroedBuffer(
        kVertexBufferStride * 4,
        wgpu::BufferUsage::Vertex | wgpu::BufferUsage::Storage | wgpu::BufferUsage::CopyDst);
    wgpu::Buffer indexBuffer = CreateZeroedBuffer(
        sizeof(int) * 4 * 2,
        wgpu::BufferUsage::Index | wgpu::BufferUsage::Storage | wgpu::BufferUsage::CopyDst);
    wgpu::Buffer uniformBuffer =
        CreateZeroedBuffer(sizeof(float), wgpu::BufferUsage::Uniform | wgpu::BufferUsage::Storage |
                                              wgpu::BufferUsage::CopyDst);
    wgpu::Buffer readonlyStorageBuffer =
        CreateZeroedBuffer(sizeof(float), wgpu::BufferUsage::Storage | wgpu::BufferUsage::CopyDst);

    wgpu::BindGroup bindGroup0 = utils::MakeBindGroup(
        device, cp.GetBindGroupLayout(0),
        {{0, vertexBuffer}, {1, indexBuffer}, {2, uniformBuffer}, {3, readonlyStorageBuffer}});
    // Write data into storage buffers in compute pass.
    wgpu::CommandEncoder encoder = device.CreateCommandEncoder();
    wgpu::ComputePassEncoder pass0 = encoder.BeginComputePass();
    pass0.SetPipeline(cp);
    pass0.SetBindGroup(0, bindGroup0);
    pass0.Dispatch(1);
    pass0.EndPass();

    // Create pipeline, bind group, and reuse buffers in render pass.
    wgpu::ShaderModule vsModule =
        utils::CreateShaderModule(device, utils::SingleShaderStage::Vertex, R"(
        #version 450
        layout(location = 0) in vec4 pos;
        void main() {
            gl_Position = pos;
        })");

    wgpu::ShaderModule fsModule =
        utils::CreateShaderModule(device, utils::SingleShaderStage::Fragment, R"(
        #version 450
        layout (set = 0, binding = 0) uniform UniformBuffer {
            float color0;
        };

        layout (set = 0, binding = 1) readonly buffer ReadonlyStorageBuffer {
            float color1;
        };

        layout(location = 0) out vec4 fragColor;
        void main() {
            fragColor = vec4(color0, color1, 0.f, 1.f);
        })");

    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, kRTSize, kRTSize);

    utils::ComboRenderPipelineDescriptor rpDesc(device);
    rpDesc.vertexStage.module = vsModule;
    rpDesc.cFragmentStage.module = fsModule;
    rpDesc.primitiveTopology = wgpu::PrimitiveTopology::TriangleStrip;
    rpDesc.cVertexState.vertexBufferCount = 1;
    rpDesc.cVertexState.cVertexBuffers[0].arrayStride = kVertexBufferStride;
    rpDesc.cVertexState.cVertexBuffers[0].attributeCount = 1;
    rpDesc.cVertexState.cAttributes[0].format = wgpu::VertexFormat::Float4;
    rpDesc.cColorStates[0].format = renderPass.colorFormat;

    wgpu::RenderPipeline rp = device.CreateRenderPipeline(&rpDesc);

    wgpu::BindGroup bindGroup1 = utils::MakeBindGroup(
        device, rp.GetBindGroupLayout(0), {{0, uniformBuffer}, {1, readonlyStorageBuffer}});

    // Read data in buffers in render pass.
    wgpu::RenderPassEncoder pass1 = encoder.BeginRenderPass(&renderPass.renderPassInfo);
    pass1.SetPipeline(rp);
    pass1.SetVertexBuffer(0, vertexBuffer);
    pass1.SetIndexBufferWithFormat(indexBuffer, wgpu::IndexFormat::Uint32, 0);
    pass1.SetBindGroup(0, bindGroup1);
    pass1.DrawIndexed(6);
    pass1.EndPass();

    wgpu::CommandBuffer commandBuffer = encoder.Finish();
    queue.Submit(1, &commandBuffer);

    // Verify the rendering result.
    int min = 1, max = kRTSize - 3;
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, min, min);
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, max, min);
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, min, max);
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, max, max);
}

// Write into a storage buffer in compute pass. Then read that data in buffer in a render pass. The
// buffer is composed of vertices, indices, uniforms and readonly storage. Data to be read in the
// buffer in render pass depend on the write operation in compute pass.
TEST_P(MultipleWriteThenMultipleReadTests, OneBuffer) {
    // Create pipeline, bind group, and a complex buffer for compute pass.
    wgpu::ShaderModule csModule =
        utils::CreateShaderModule(device, utils::SingleShaderStage::Compute, R"(
        #version 450
        layout(std140, set = 0, binding = 0) buffer Contents {
            // Every single float (and every float in an array, and every single vec2, vec3, and
            // every column in mat2/mat3, etc) uses the same amount of memory as vec4 (float4).
            vec4 pos[4];
            vec4 padding0[12];
            ivec4 indices[2];
            ivec4 padding1[14];
            float color0;
            float padding2[15];
            float color1;
        };

        void main() {
            pos[0] = vec4(-1.f, 1.f, 0.f, 1.f);
            pos[1] = vec4(1.f, 1.f, 0.f, 1.f);
            pos[2] = vec4(1.f, -1.f, 0.f, 1.f);
            pos[3] = vec4(-1.f, -1.f, 0.f, 1.f);
            int dummy = 0;
            indices[0] = ivec4(0, 1, 2, 0);
            indices[1] = ivec4(2, 3, dummy, dummy);
            color0 = 1.0;
            color1 = 1.0;
        })");

    wgpu::ComputePipelineDescriptor cpDesc;
    cpDesc.computeStage.module = csModule;
    cpDesc.computeStage.entryPoint = "main";
    wgpu::ComputePipeline cp = device.CreateComputePipeline(&cpDesc);
    struct Data {
        float pos[4][4];
        char padding0[256 - sizeof(float) * 16];
        int indices[2][4];
        char padding1[256 - sizeof(int) * 8];
        float color0[4];
        char padding2[256 - sizeof(float) * 4];
        float color1[4];
    };
    wgpu::Buffer buffer = CreateZeroedBuffer(
        sizeof(Data), wgpu::BufferUsage::Vertex | wgpu::BufferUsage::Index |
                          wgpu::BufferUsage::Uniform | wgpu::BufferUsage::Storage |
                          wgpu::BufferUsage::CopyDst);
    wgpu::BindGroup bindGroup0 =
        utils::MakeBindGroup(device, cp.GetBindGroupLayout(0), {{0, buffer}});

    // Write various data (vertices, indices, and uniforms) into the buffer in compute pass.
    wgpu::CommandEncoder encoder = device.CreateCommandEncoder();
    wgpu::ComputePassEncoder pass0 = encoder.BeginComputePass();
    pass0.SetPipeline(cp);
    pass0.SetBindGroup(0, bindGroup0);
    pass0.Dispatch(1);
    pass0.EndPass();

    // Create pipeline, bind group, and reuse the buffer in render pass.
    wgpu::ShaderModule vsModule =
        utils::CreateShaderModule(device, utils::SingleShaderStage::Vertex, R"(
        #version 450
        layout(location = 0) in vec4 pos;
        void main() {
            gl_Position = pos;
        })");

    wgpu::ShaderModule fsModule =
        utils::CreateShaderModule(device, utils::SingleShaderStage::Fragment, R"(
        #version 450
        layout (set = 0, binding = 0) uniform UniformBuffer {
            float color0;
        };

        layout (set = 0, binding = 1) readonly buffer ReadonlyStorageBuffer {
            float color1;
        };

        layout(location = 0) out vec4 fragColor;
        void main() {
            fragColor = vec4(color0, color1, 0.f, 1.f);
        })");

    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, kRTSize, kRTSize);

    utils::ComboRenderPipelineDescriptor rpDesc(device);
    rpDesc.vertexStage.module = vsModule;
    rpDesc.cFragmentStage.module = fsModule;
    rpDesc.primitiveTopology = wgpu::PrimitiveTopology::TriangleStrip;
    rpDesc.cVertexState.vertexBufferCount = 1;
    rpDesc.cVertexState.cVertexBuffers[0].arrayStride = kVertexBufferStride;
    rpDesc.cVertexState.cVertexBuffers[0].attributeCount = 1;
    rpDesc.cVertexState.cAttributes[0].format = wgpu::VertexFormat::Float4;
    rpDesc.cColorStates[0].format = renderPass.colorFormat;

    wgpu::RenderPipeline rp = device.CreateRenderPipeline(&rpDesc);

    wgpu::BindGroup bindGroup1 =
        utils::MakeBindGroup(device, rp.GetBindGroupLayout(0),
                             {{0, buffer, offsetof(Data, color0), sizeof(float)},
                              {1, buffer, offsetof(Data, color1), sizeof(float)}});

    // Read various data in the buffer in render pass.
    wgpu::RenderPassEncoder pass1 = encoder.BeginRenderPass(&renderPass.renderPassInfo);
    pass1.SetPipeline(rp);
    pass1.SetVertexBuffer(0, buffer);
    pass1.SetIndexBufferWithFormat(buffer, wgpu::IndexFormat::Uint32, offsetof(Data, indices));
    pass1.SetBindGroup(0, bindGroup1);
    pass1.DrawIndexed(6);
    pass1.EndPass();

    wgpu::CommandBuffer commandBuffer = encoder.Finish();
    queue.Submit(1, &commandBuffer);

    // Verify the rendering result.
    int min = 1, max = kRTSize - 3;
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, min, min);
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, max, min);
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, min, max);
    EXPECT_PIXEL_RGBA8_EQ(RGBA8::kYellow, renderPass.color, max, max);
}

DAWN_INSTANTIATE_TEST(MultipleWriteThenMultipleReadTests,
                      D3D12Backend(),
                      MetalBackend(),
                      OpenGLBackend(),
                      VulkanBackend());