//
// Copyright 2016 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.
//
// VertexArrayVk.cpp:
//    Implements the class methods for VertexArrayVk.
//

#ifdef UNSAFE_BUFFERS_BUILD
#    pragma allow_unsafe_buffers
#endif

#include "libANGLE/renderer/vulkan/VertexArrayVk.h"

#include "common/debug.h"
#include "common/utilities.h"
#include "libANGLE/Context.h"
#include "libANGLE/renderer/vulkan/BufferVk.h"
#include "libANGLE/renderer/vulkan/ContextVk.h"
#include "libANGLE/renderer/vulkan/FramebufferVk.h"
#include "libANGLE/renderer/vulkan/vk_format_utils.h"
#include "libANGLE/renderer/vulkan/vk_renderer.h"
#include "libANGLE/renderer/vulkan/vk_resource.h"

namespace rx
{
namespace
{
constexpr int kStreamIndexBufferCachedIndexCount = 6;
constexpr int kMaxCachedStreamIndexBuffers       = 4;
constexpr size_t kDefaultValueSize               = sizeof(gl::VertexAttribCurrentValueData::Values);

ANGLE_INLINE bool BindingIsAligned(const angle::Format &angleFormat,
                                   VkDeviceSize offset,
                                   GLuint stride)
{
    ASSERT(stride != 0);
    GLuint mask          = angleFormat.componentAlignmentMask;
    if (mask != std::numeric_limits<GLuint>::max())
    {
        return ((offset & mask) == 0 && (stride & mask) == 0);
    }
    else
    {
        // To perform the GPU conversion for formats with components that aren't byte-aligned
        // (for example, A2BGR10 or RGB10A2), one element has to be placed in 4 bytes to perform
        // the compute shader. So, binding offset and stride has to be aligned to formatSize.
        unsigned int formatSize = angleFormat.pixelBytes;
        return (offset % formatSize == 0) && (stride % formatSize == 0);
    }
}

ANGLE_INLINE bool ClientBindingAligned(const gl::VertexAttribute &attrib,
                                       GLuint stride,
                                       size_t alignment)
{
    return reinterpret_cast<intptr_t>(attrib.pointer) % alignment == 0 && stride % alignment == 0;
}

bool ShouldCombineAttributes(vk::Renderer *renderer,
                             const gl::VertexAttribute &attrib,
                             const gl::VertexBinding &binding)
{
    if (!renderer->getFeatures().enableMergeClientAttribBuffer.enabled)
    {
        return false;
    }
    const vk::Format &vertexFormat = renderer->getFormat(attrib.format->id);
    return !vertexFormat.getVertexLoadRequiresConversion() && binding.getDivisor() == 0 &&
           ClientBindingAligned(attrib, binding.getStride(),
                                vertexFormat.getVertexInputAlignment());
}

void WarnOnVertexFormatConversion(ContextVk *contextVk, const vk::Format &vertexFormat)
{
    if (!vertexFormat.getVertexLoadRequiresConversion())
    {
        return;
    }

    ANGLE_VK_PERF_WARNING(
        contextVk, GL_DEBUG_SEVERITY_LOW,
        "The Vulkan driver does not support vertex attribute format 0x%04X, emulating with 0x%04X",
        vertexFormat.getIntendedFormat().glInternalFormat,
        vertexFormat.getActualBufferFormat().glInternalFormat);
}

angle::Result StreamVertexData(ContextVk *contextVk,
                               vk::BufferHelper *dstBufferHelper,
                               const uint8_t *srcData,
                               size_t bytesToCopy,
                               size_t dstOffset,
                               size_t vertexCount,
                               size_t srcStride,
                               VertexCopyFunction vertexLoadFunction)
{
    vk::Renderer *renderer = contextVk->getRenderer();

    // If the source pointer is null, it should not be accessed.
    if (srcData == nullptr)
    {
        return angle::Result::Continue;
    }

    uint8_t *dst = dstBufferHelper->getMappedMemory() + dstOffset;

    if (vertexLoadFunction != nullptr)
    {
        vertexLoadFunction(srcData, srcStride, vertexCount, dst);
    }
    else
    {
        memcpy(dst, srcData, bytesToCopy);
    }

    ANGLE_TRY(dstBufferHelper->flush(renderer));

    return angle::Result::Continue;
}

angle::Result StreamVertexDataWithDivisor(ContextVk *contextVk,
                                          vk::BufferHelper *dstBufferHelper,
                                          const uint8_t *srcData,
                                          size_t bytesToAllocate,
                                          size_t srcStride,
                                          size_t dstStride,
                                          VertexCopyFunction vertexLoadFunction,
                                          uint32_t divisor,
                                          size_t numSrcVertices)
{
    vk::Renderer *renderer = contextVk->getRenderer();

    uint8_t *dst = dstBufferHelper->getMappedMemory();

    // Each source vertex is used `divisor` times before advancing. Clamp to avoid OOB reads.
    size_t clampedSize = std::min(numSrcVertices * dstStride * divisor, bytesToAllocate);

    ASSERT(clampedSize % dstStride == 0);
    ASSERT(divisor > 0);

    uint32_t srcVertexUseCount = 0;
    for (size_t dataCopied = 0; dataCopied < clampedSize; dataCopied += dstStride)
    {
        vertexLoadFunction(srcData, srcStride, 1, dst);
        srcVertexUseCount++;
        if (srcVertexUseCount == divisor)
        {
            srcData += srcStride;
            srcVertexUseCount = 0;
        }
        dst += dstStride;
    }

    // Satisfy robustness constraints (only if extension enabled)
    if (contextVk->getExtensions().robustnessAny())
    {
        if (clampedSize < bytesToAllocate)
        {
            memset(dst, 0, bytesToAllocate - clampedSize);
        }
    }

    ANGLE_TRY(dstBufferHelper->flush(renderer));

    return angle::Result::Continue;
}

size_t GetVertexCountForRange(GLint64 srcBufferBytes,
                              uint32_t srcFormatSize,
                              uint32_t srcVertexStride)
{
    ASSERT(srcVertexStride != 0);
    ASSERT(srcFormatSize != 0);

    if (srcBufferBytes < srcFormatSize)
    {
        return 0;
    }

    size_t numVertices =
        static_cast<size_t>(srcBufferBytes + srcVertexStride - 1) / srcVertexStride;
    return numVertices;
}

size_t GetVertexCount(BufferVk *srcBuffer, const gl::VertexBinding &binding, uint32_t srcFormatSize)
{
    // Bytes usable for vertex data.
    GLint64 bytes = srcBuffer->getSize() - binding.getOffset();
    GLuint stride = binding.getStride();
    if (stride == 0)
    {
        stride = srcFormatSize;
    }
    return GetVertexCountForRange(bytes, srcFormatSize, stride);
}

angle::Result CalculateMaxVertexCountForConversion(ContextVk *contextVk,
                                                   BufferVk *srcBuffer,
                                                   VertexConversionBuffer *conversion,
                                                   const angle::Format &srcFormat,
                                                   const angle::Format &dstFormat,
                                                   size_t *maxNumVerticesOut)
{
    // Initialize numVertices to 0
    *maxNumVerticesOut = 0;

    unsigned srcFormatSize = srcFormat.pixelBytes;
    unsigned dstFormatSize = dstFormat.pixelBytes;

    uint32_t srcStride = conversion->getCacheKey().stride;
    uint32_t dstStride = dstFormatSize;

    ASSERT(srcStride != 0);
    ASSERT(conversion->dirty());

    // Start the range with the range from the the beginning of the buffer to the end of
    // buffer. Then scissor it with the dirtyRange.
    size_t srcOffset  = conversion->getCacheKey().offset;
    GLint64 srcLength = srcBuffer->getSize() - srcOffset;

    // The max number of vertices from binding to the end of the buffer
    size_t maxNumVertices = GetVertexCountForRange(srcLength, srcFormatSize, srcStride);
    if (maxNumVertices == 0)
    {
        return angle::Result::Continue;
    }

    // Allocate buffer for results
    vk::MemoryHostVisibility hostVisible = conversion->getCacheKey().hostVisible
                                               ? vk::MemoryHostVisibility::Visible
                                               : vk::MemoryHostVisibility::NonVisible;
    ANGLE_TRY(contextVk->initBufferForVertexConversion(conversion, maxNumVertices * dstStride,
                                                       hostVisible));

    // Calculate numVertices to convert
    *maxNumVerticesOut = GetVertexCountForRange(srcLength, srcFormatSize, srcStride);

    return angle::Result::Continue;
}

void CalculateOffsetAndVertexCountForDirtyRange(BufferVk *bufferVk,
                                                VertexConversionBuffer *conversion,
                                                const angle::Format &srcFormat,
                                                const angle::Format &dstFormat,
                                                const RangeDeviceSize &dirtyRange,
                                                uint32_t *srcOffsetOut,
                                                uint32_t *dstOffsetOut,
                                                uint32_t *numVerticesOut)
{
    ASSERT(!dirtyRange.empty());
    unsigned srcFormatSize = srcFormat.pixelBytes;
    unsigned dstFormatSize = dstFormat.pixelBytes;

    uint32_t srcStride = conversion->getCacheKey().stride;
    uint32_t dstStride = dstFormatSize;

    ASSERT(srcStride != 0);
    ASSERT(conversion->dirty());

    // Start the range with the range from the the beginning of the buffer to the end of
    // buffer. Then scissor it with the dirtyRange.
    size_t srcOffset = conversion->getCacheKey().offset;
    size_t dstOffset = 0;

    GLint64 srcLength = bufferVk->getSize() - srcOffset;

    // Adjust offset to the begining of the dirty range
    if (dirtyRange.low() > srcOffset)
    {
        size_t vertexCountToSkip = (static_cast<size_t>(dirtyRange.low()) - srcOffset) / srcStride;
        size_t srcBytesToSkip    = vertexCountToSkip * srcStride;
        size_t dstBytesToSkip    = vertexCountToSkip * dstStride;
        srcOffset += srcBytesToSkip;
        srcLength -= srcBytesToSkip;
        dstOffset += dstBytesToSkip;
    }

    // Adjust dstOffset to align to 4 bytes. The GPU convert code path always write a uint32_t and
    // must aligned at 4 bytes. We could possibly make it able to store at unaligned uint32_t but
    // performance will be worse than just convert a few extra data.
    while ((dstOffset % 4) != 0)
    {
        dstOffset -= dstStride;
        srcOffset -= srcStride;
        srcLength += srcStride;
    }

    // Adjust length
    if (dirtyRange.high() < static_cast<VkDeviceSize>(bufferVk->getSize()))
    {
        srcLength = dirtyRange.high() - srcOffset;
    }

    // Calculate numVertices to convert
    size_t numVertices = GetVertexCountForRange(srcLength, srcFormatSize, srcStride);

    *numVerticesOut = static_cast<uint32_t>(numVertices);
    *srcOffsetOut   = static_cast<uint32_t>(srcOffset);
    *dstOffsetOut   = static_cast<uint32_t>(dstOffset);
}
}  // anonymous namespace

VertexArrayVk::VertexArrayVk(ContextVk *contextVk,
                             const gl::VertexArrayState &state,
                             const gl::VertexArrayBuffers &vertexArrayBuffers)
    : VertexArrayImpl(state, vertexArrayBuffers),
      mCurrentArrayBufferHandles{},
      mCurrentArrayBufferOffsets{},
      mCurrentArrayBuffers{},
      mVertexInputBindingDesc{},
      mVertexInputAttribDesc{},
      mCurrentElementArrayBuffer(nullptr),
      mLineLoopHelper(contextVk->getRenderer()),
      mDirtyLineLoopTranslation(true)
{
    vk::BufferHelper &emptyBuffer = contextVk->getEmptyBuffer();

    mCurrentArrayBufferHandles.fill(emptyBuffer.getBuffer().getHandle());
    mCurrentArrayBufferOffsets.fill(0);
    mCurrentArrayBuffers.fill(&emptyBuffer);

    for (uint32_t attribIndex = 0; attribIndex < mVertexInputBindingDesc.size(); attribIndex++)
    {
        mVertexInputBindingDesc[attribIndex] = VkVertexInputBindingDescription2EXT{
            VK_STRUCTURE_TYPE_VERTEX_INPUT_BINDING_DESCRIPTION_2_EXT,    nullptr, attribIndex, 0,
            static_cast<VkVertexInputRate>(VK_VERTEX_INPUT_RATE_VERTEX), 0};
    }
    for (uint32_t attribIndex = 0; attribIndex < mVertexInputAttribDesc.size(); attribIndex++)
    {
        mVertexInputAttribDesc[attribIndex] = VkVertexInputAttributeDescription2EXT{
            VK_STRUCTURE_TYPE_VERTEX_INPUT_ATTRIBUTE_DESCRIPTION_2_EXT,
            nullptr,
            attribIndex,
            attribIndex,
            VK_FORMAT_R8G8B8A8_UNORM,
            0};
    }

    mBindingDirtyBitsRequiresPipelineUpdate.set(gl::VertexArray::DIRTY_BINDING_DIVISOR);
    if (!contextVk->getFeatures().useVertexInputBindingStrideDynamicState.enabled)
    {
        mBindingDirtyBitsRequiresPipelineUpdate.set(gl::VertexArray::DIRTY_BINDING_STRIDE);
    }

    // All but DIRTY_ATTRIB_POINTER_BUFFER requires graphics pipeline update
    mAttribDirtyBitsRequiresPipelineUpdate.set(gl::VertexArray::DIRTY_ATTRIB_ENABLED);
    mAttribDirtyBitsRequiresPipelineUpdate.set(gl::VertexArray::DIRTY_ATTRIB_POINTER);
    mAttribDirtyBitsRequiresPipelineUpdate.set(gl::VertexArray::DIRTY_ATTRIB_FORMAT);
    mAttribDirtyBitsRequiresPipelineUpdate.set(gl::VertexArray::DIRTY_ATTRIB_BINDING);
}

VertexArrayVk::~VertexArrayVk() {}

void VertexArrayVk::destroy(const gl::Context *context)
{
    ContextVk *contextVk = vk::GetImpl(context);

    for (std::unique_ptr<vk::BufferHelper> &buffer : mCachedStreamIndexBuffers)
    {
        buffer->release(contextVk);
    }

    mStreamedIndexData.release(contextVk);
    mTranslatedByteIndexData.release(contextVk);
    mTranslatedByteIndirectData.release(contextVk);
    mLineLoopHelper.release(contextVk);
}

angle::Result VertexArrayVk::convertIndexBufferGPU(ContextVk *contextVk,
                                                   BufferVk *bufferVk,
                                                   const void *indices)
{
    intptr_t offsetIntoSrcData = reinterpret_cast<intptr_t>(indices);
    size_t srcDataSize         = static_cast<size_t>(bufferVk->getSize()) - offsetIntoSrcData;

    // Allocate buffer for results
    ANGLE_TRY(contextVk->initBufferForVertexConversion(&mTranslatedByteIndexData,
                                                       sizeof(GLushort) * srcDataSize,
                                                       vk::MemoryHostVisibility::NonVisible));
    mCurrentElementArrayBuffer = mTranslatedByteIndexData.getBuffer();

    vk::BufferHelper *dst = mTranslatedByteIndexData.getBuffer();
    vk::BufferHelper *src = &bufferVk->getBuffer();

    // Copy relevant section of the source into destination at allocated offset.  Note that the
    // offset returned by allocate() above is in bytes. As is the indices offset pointer.
    UtilsVk::ConvertIndexParameters params = {};
    params.srcOffset                       = static_cast<uint32_t>(offsetIntoSrcData);
    params.dstOffset                       = 0;
    params.maxIndex                        = static_cast<uint32_t>(bufferVk->getSize());

    ANGLE_TRY(contextVk->getUtils().convertIndexBuffer(contextVk, dst, src, params));
    mTranslatedByteIndexData.clearDirty();

    return angle::Result::Continue;
}

angle::Result VertexArrayVk::convertIndexBufferIndirectGPU(ContextVk *contextVk,
                                                           vk::BufferHelper *srcIndirectBuf,
                                                           VkDeviceSize srcIndirectBufOffset,
                                                           vk::BufferHelper **indirectBufferVkOut)
{
    size_t srcDataSize = static_cast<size_t>(mCurrentElementArrayBuffer->getSize());
    ASSERT(mCurrentElementArrayBuffer == &vk::GetImpl(getElementArrayBuffer())->getBuffer());

    vk::BufferHelper *srcIndexBuf = mCurrentElementArrayBuffer;

    // Allocate buffer for results
    ANGLE_TRY(contextVk->initBufferForVertexConversion(&mTranslatedByteIndexData,
                                                       sizeof(GLushort) * srcDataSize,
                                                       vk::MemoryHostVisibility::NonVisible));
    vk::BufferHelper *dstIndexBuf = mTranslatedByteIndexData.getBuffer();

    ANGLE_TRY(contextVk->initBufferForVertexConversion(&mTranslatedByteIndirectData,
                                                       sizeof(VkDrawIndexedIndirectCommand),
                                                       vk::MemoryHostVisibility::NonVisible));
    vk::BufferHelper *dstIndirectBuf = mTranslatedByteIndirectData.getBuffer();

    // Save new element array buffer
    mCurrentElementArrayBuffer = dstIndexBuf;
    // Tell caller what new indirect buffer is
    *indirectBufferVkOut = dstIndirectBuf;

    // Copy relevant section of the source into destination at allocated offset.  Note that the
    // offset returned by allocate() above is in bytes. As is the indices offset pointer.
    UtilsVk::ConvertIndexIndirectParameters params = {};
    params.srcIndirectBufOffset                    = static_cast<uint32_t>(srcIndirectBufOffset);
    params.srcIndexBufOffset                       = 0;
    params.dstIndexBufOffset                       = 0;
    params.maxIndex                                = static_cast<uint32_t>(srcDataSize);
    params.dstIndirectBufOffset                    = 0;

    ANGLE_TRY(contextVk->getUtils().convertIndexIndirectBuffer(
        contextVk, srcIndirectBuf, srcIndexBuf, dstIndirectBuf, dstIndexBuf, params));

    mTranslatedByteIndexData.clearDirty();
    mTranslatedByteIndirectData.clearDirty();

    return angle::Result::Continue;
}

angle::Result VertexArrayVk::handleLineLoopIndexIndirect(ContextVk *contextVk,
                                                         gl::DrawElementsType glIndexType,
                                                         vk::BufferHelper *srcIndexBuffer,
                                                         vk::BufferHelper *srcIndirectBuffer,
                                                         VkDeviceSize indirectBufferOffset,
                                                         vk::BufferHelper **indexBufferOut,
                                                         vk::BufferHelper **indirectBufferOut)
{
    return mLineLoopHelper.streamIndicesIndirect(contextVk, glIndexType, srcIndexBuffer,
                                                 srcIndirectBuffer, indirectBufferOffset,
                                                 indexBufferOut, indirectBufferOut);
}

angle::Result VertexArrayVk::handleLineLoopIndirectDraw(const gl::Context *context,
                                                        vk::BufferHelper *indirectBufferVk,
                                                        VkDeviceSize indirectBufferOffset,
                                                        vk::BufferHelper **indexBufferOut,
                                                        vk::BufferHelper **indirectBufferOut)
{
    size_t maxVertexCount = 0;
    ContextVk *contextVk  = vk::GetImpl(context);
    const gl::AttributesMask activeAttribs = context->getActiveBufferedAttribsMask();

    const auto &attribs  = mState.getVertexAttributes();
    const auto &bindings = mState.getVertexBindings();

    for (size_t attribIndex : activeAttribs)
    {
        const gl::VertexAttribute &attrib = attribs[attribIndex];
        ASSERT(attrib.enabled);
        VkDeviceSize bufSize             = getCurrentArrayBuffers()[attribIndex]->getSize();
        const gl::VertexBinding &binding = bindings[attrib.bindingIndex];
        size_t stride                    = binding.getStride();
        size_t vertexCount               = static_cast<size_t>(bufSize / stride);
        if (vertexCount > maxVertexCount)
        {
            maxVertexCount = vertexCount;
        }
    }
    ANGLE_TRY(mLineLoopHelper.streamArrayIndirect(contextVk, maxVertexCount + 1, indirectBufferVk,
                                                  indirectBufferOffset, indexBufferOut,
                                                  indirectBufferOut));

    return angle::Result::Continue;
}

angle::Result VertexArrayVk::convertIndexBufferCPU(ContextVk *contextVk,
                                                   gl::DrawElementsType indexType,
                                                   size_t indexCount,
                                                   const void *sourcePointer,
                                                   BufferBindingDirty *bindingDirty)
{
    ASSERT(!getElementArrayBuffer() || indexType == gl::DrawElementsType::UnsignedByte);
    vk::Renderer *renderer = contextVk->getRenderer();
    size_t elementSize     = contextVk->getVkIndexTypeSize(indexType);
    const size_t amount    = elementSize * indexCount;

    // Applications often time draw a quad with two triangles. This is try to catch all the
    // common used element array buffer with pre-created BufferHelper objects to improve
    // performance.
    if (indexCount == kStreamIndexBufferCachedIndexCount &&
        indexType == gl::DrawElementsType::UnsignedShort)
    {
        for (std::unique_ptr<vk::BufferHelper> &buffer : mCachedStreamIndexBuffers)
        {
            void *ptr = buffer->getMappedMemory();
            if (memcmp(sourcePointer, ptr, amount) == 0)
            {
                // Found a matching cached buffer, use the cached internal index buffer.
                *bindingDirty              = mCurrentElementArrayBuffer == buffer.get()
                                                 ? BufferBindingDirty::No
                                                 : BufferBindingDirty::Yes;
                mCurrentElementArrayBuffer = buffer.get();
                return angle::Result::Continue;
            }
        }

        // If we still have capacity, cache this index buffer for future use.
        if (mCachedStreamIndexBuffers.size() < kMaxCachedStreamIndexBuffers)
        {
            std::unique_ptr<vk::BufferHelper> buffer = std::make_unique<vk::BufferHelper>();
            ANGLE_TRY(contextVk->initBufferAllocation(
                buffer.get(),
                renderer->getVertexConversionBufferMemoryTypeIndex(
                    vk::MemoryHostVisibility::Visible),
                amount, renderer->getVertexConversionBufferAlignment(), BufferUsageType::Static));
            memcpy(buffer->getMappedMemory(), sourcePointer, amount);
            ANGLE_TRY(buffer->flush(renderer));

            mCachedStreamIndexBuffers.push_back(std::move(buffer));

            *bindingDirty              = BufferBindingDirty::Yes;
            mCurrentElementArrayBuffer = mCachedStreamIndexBuffers.back().get();
            return angle::Result::Continue;
        }
    }

    ANGLE_TRY(contextVk->initBufferForVertexConversion(&mStreamedIndexData, amount,
                                                       vk::MemoryHostVisibility::Visible));
    mCurrentElementArrayBuffer = mStreamedIndexData.getBuffer();
    GLubyte *dst               = mCurrentElementArrayBuffer->getMappedMemory();
    *bindingDirty              = BufferBindingDirty::Yes;

    if (contextVk->shouldConvertUint8VkIndexType(indexType))
    {
        // Unsigned bytes don't have direct support in Vulkan so we have to expand the
        // memory to a GLushort.
        const GLubyte *in     = static_cast<const GLubyte *>(sourcePointer);
        GLushort *expandedDst = reinterpret_cast<GLushort *>(dst);
        bool primitiveRestart = contextVk->getState().isPrimitiveRestartEnabled();

        constexpr GLubyte kUnsignedByteRestartValue   = 0xFF;
        constexpr GLushort kUnsignedShortRestartValue = 0xFFFF;

        if (primitiveRestart)
        {
            for (size_t index = 0; index < indexCount; index++)
            {
                GLushort value = static_cast<GLushort>(in[index]);
                if (in[index] == kUnsignedByteRestartValue)
                {
                    // Convert from 8-bit restart value to 16-bit restart value
                    value = kUnsignedShortRestartValue;
                }
                expandedDst[index] = value;
            }
        }
        else
        {
            // Fast path for common case.
            for (size_t index = 0; index < indexCount; index++)
            {
                expandedDst[index] = static_cast<GLushort>(in[index]);
            }
        }
    }
    else
    {
        // The primitive restart value is the same for OpenGL and Vulkan,
        // so there's no need to perform any conversion.
        memcpy(dst, sourcePointer, amount);
    }

    mStreamedIndexData.clearDirty();

    return mCurrentElementArrayBuffer->flush(contextVk->getRenderer());
}

// We assume the buffer is completely full of the same kind of data and convert
// and/or align it as we copy it to a buffer. The assumption could be wrong
// but the alternative of copying it piecemeal on each draw would have a lot more
// overhead.
angle::Result VertexArrayVk::convertVertexBufferGPU(ContextVk *contextVk,
                                                    BufferVk *srcBuffer,
                                                    VertexConversionBuffer *conversion,
                                                    const angle::Format &srcFormat,
                                                    const angle::Format &dstFormat)
{
    uint32_t srcStride = conversion->getCacheKey().stride;
    ASSERT(srcStride % (srcFormat.pixelBytes / srcFormat.channelCount) == 0);

    size_t maxNumVertices;
    ANGLE_TRY(CalculateMaxVertexCountForConversion(contextVk, srcBuffer, conversion, srcFormat,
                                                   dstFormat, &maxNumVertices));
    if (maxNumVertices == 0)
    {
        return angle::Result::Continue;
    }

    vk::BufferHelper *srcBufferHelper = &srcBuffer->getBuffer();
    vk::BufferHelper *dstBuffer       = conversion->getBuffer();

    UtilsVk::OffsetAndVertexCounts additionalOffsetVertexCounts;

    UtilsVk::ConvertVertexParameters params;
    params.srcFormat   = &srcFormat;
    params.dstFormat   = &dstFormat;
    params.srcStride   = srcStride;
    params.vertexCount = 0;

    if (conversion->isEntireBufferDirty())
    {
        params.vertexCount = static_cast<uint32_t>(maxNumVertices);
        params.srcOffset   = static_cast<uint32_t>(conversion->getCacheKey().offset);
        params.dstOffset   = 0;
    }
    else
    {
        // dirtyRanges may overlap with each other. Try to do a quick merge to reduce the number of
        // dispatch calls as well as avoid redundant conversion in the overlapped area.
        conversion->consolidateDirtyRanges();

        const std::vector<RangeDeviceSize> &dirtyRanges = conversion->getDirtyBufferRanges();
        additionalOffsetVertexCounts.reserve(dirtyRanges.size());

        for (const RangeDeviceSize &dirtyRange : dirtyRanges)
        {
            if (dirtyRange.empty())
            {
                // consolidateDirtyRanges may end up with invalid range if it gets merged.
                continue;
            }

            uint32_t srcOffset, dstOffset, numVertices;
            CalculateOffsetAndVertexCountForDirtyRange(srcBuffer, conversion, srcFormat, dstFormat,
                                                       dirtyRange, &srcOffset, &dstOffset,
                                                       &numVertices);
            if (params.vertexCount == 0)
            {
                params.vertexCount = numVertices;
                params.srcOffset   = srcOffset;
                params.dstOffset   = dstOffset;
            }
            else
            {
                additionalOffsetVertexCounts.emplace_back();
                additionalOffsetVertexCounts.back().srcOffset   = srcOffset;
                additionalOffsetVertexCounts.back().dstOffset   = dstOffset;
                additionalOffsetVertexCounts.back().vertexCount = numVertices;
            }
        }
    }
    ANGLE_TRY(contextVk->getUtils().convertVertexBuffer(contextVk, dstBuffer, srcBufferHelper,
                                                        params, additionalOffsetVertexCounts));
    conversion->clearDirty();

    return angle::Result::Continue;
}

angle::Result VertexArrayVk::convertVertexBufferCPU(ContextVk *contextVk,
                                                    BufferVk *srcBuffer,
                                                    VertexConversionBuffer *conversion,
                                                    const angle::Format &srcFormat,
                                                    const angle::Format &dstFormat,
                                                    const VertexCopyFunction vertexLoadFunction)
{
    ANGLE_TRACE_EVENT0("gpu.angle", "VertexArrayVk::convertVertexBufferCpu");

    size_t maxNumVertices;
    ANGLE_TRY(CalculateMaxVertexCountForConversion(contextVk, srcBuffer, conversion, srcFormat,
                                                   dstFormat, &maxNumVertices));
    if (maxNumVertices == 0)
    {
        return angle::Result::Continue;
    }

    uint8_t *src = nullptr;
    ANGLE_TRY(srcBuffer->mapForReadAccessOnly(contextVk, reinterpret_cast<void **>(&src)));
    uint32_t srcStride      = conversion->getCacheKey().stride;

    if (conversion->isEntireBufferDirty())
    {
        size_t srcOffset        = conversion->getCacheKey().offset;
        size_t dstOffset        = 0;
        const uint8_t *srcBytes = src + srcOffset;
        size_t bytesToCopy      = maxNumVertices * dstFormat.pixelBytes;
        ANGLE_TRY(StreamVertexData(contextVk, conversion->getBuffer(), srcBytes, bytesToCopy,
                                   dstOffset, maxNumVertices, srcStride, vertexLoadFunction));
    }
    else
    {
        // dirtyRanges may overlap with each other. Try to do a quick merge to avoid redundant
        // conversion in the overlapped area.
        conversion->consolidateDirtyRanges();

        const std::vector<RangeDeviceSize> &dirtyRanges = conversion->getDirtyBufferRanges();
        for (const RangeDeviceSize &dirtyRange : dirtyRanges)
        {
            if (dirtyRange.empty())
            {
                // consolidateDirtyRanges may end up with invalid range if it gets merged.
                continue;
            }

            uint32_t srcOffset, dstOffset, numVertices;
            CalculateOffsetAndVertexCountForDirtyRange(srcBuffer, conversion, srcFormat, dstFormat,
                                                       dirtyRange, &srcOffset, &dstOffset,
                                                       &numVertices);

            if (numVertices > 0)
            {
                const uint8_t *srcBytes = src + srcOffset;
                size_t bytesToCopy      = maxNumVertices * dstFormat.pixelBytes;
                ANGLE_TRY(StreamVertexData(contextVk, conversion->getBuffer(), srcBytes,
                                           bytesToCopy, dstOffset, maxNumVertices, srcStride,
                                           vertexLoadFunction));
            }
        }
    }

    conversion->clearDirty();
    ANGLE_TRY(srcBuffer->unmapReadAccessOnly(contextVk));

    return angle::Result::Continue;
}

void VertexArrayVk::updateCurrentElementArrayBuffer()
{
    ASSERT(getElementArrayBuffer() != nullptr);
    ASSERT(getElementArrayBuffer()->getSize() > 0);

    BufferVk *bufferVk         = vk::GetImpl(getElementArrayBuffer());
    mCurrentElementArrayBuffer = &bufferVk->getBuffer();
}

gl::VertexArray::DirtyBits VertexArrayVk::checkBufferForDirtyBits(
    const gl::Context *context,
    const gl::VertexArrayBufferBindingMask bufferBindingMask)
{
    gl::VertexArray::DirtyBits dirtyBits;

    const std::vector<gl::VertexAttribute> &attribs = mState.getVertexAttributes();
    const std::vector<gl::VertexBinding> &bindings  = mState.getVertexBindings();

    // Element buffer is not in bindings yet, has to handle separately.
    dirtyBits.set(gl::VertexArray::DIRTY_BIT_ELEMENT_ARRAY_BUFFER);

    gl::VertexArrayBufferBindingMask bindingMask = bufferBindingMask;
    bindingMask.reset(gl::kElementArrayBufferIndex);

    for (size_t bindingIndex : bindingMask)
    {
        const gl::Buffer *bufferGL    = getVertexArrayBuffer(bindingIndex);
        vk::BufferSerial bufferSerial = vk::GetImpl(bufferGL)->getBufferSerial();
        gl::AttributesMask enabledAttributeMask =
            bindings[bindingIndex].getBoundAttributesMask() & mState.getEnabledAttributesMask();
        for (size_t attribIndex : enabledAttributeMask)
        {
            ASSERT(attribs[attribIndex].enabled);
            if (!bufferSerial.valid() || bufferSerial != mCurrentArrayBufferSerial[attribIndex])
            {
                dirtyBits.set(gl::VertexArray::DIRTY_BIT_BINDING_0 + bindingIndex);
                break;
            }
        }
    }

    // buffer content may have changed when it became non-current. In that case we always assume
    // buffer data has changed.
    if (mContentsObserverBindingsMask.any())
    {
        uint64_t bits = mContentsObserverBindingsMask.bits();
        bits <<= gl::VertexArray::DIRTY_BIT_BUFFER_DATA_0;
        dirtyBits |= gl::VertexArray::DirtyBits(bits);
    }

    return dirtyBits;
}

angle::Result VertexArrayVk::syncState(const gl::Context *context,
                                       const gl::VertexArray::DirtyBits &dirtyBits,
                                       gl::VertexArray::DirtyAttribBitsArray *attribBits,
                                       gl::VertexArray::DirtyBindingBitsArray *bindingBits)
{
    ASSERT(dirtyBits.any());

    ContextVk *contextVk = vk::GetImpl(context);
    vk::Renderer *renderer = contextVk->getRenderer();
    contextVk->getPerfCounters().vertexArraySyncStateCalls++;

    const std::vector<gl::VertexAttribute> &attribs = mState.getVertexAttributes();
    const std::vector<gl::VertexBinding> &bindings  = mState.getVertexBindings();

    // Split out dirtyBits into bindingBits and attributeBits
    gl::BufferBindingMask bufferBindingDirtyBits(
        static_cast<uint32_t>(dirtyBits.bits() >> gl::VertexArray::DIRTY_BIT_BINDING_0));
    gl::BufferBindingMask bufferDataDirtyBits(
        static_cast<uint32_t>(dirtyBits.bits() >> gl::VertexArray::DIRTY_BIT_BUFFER_DATA_0));
    gl::AttributesMask attribDirtyBits(
        static_cast<uint32_t>(dirtyBits.bits() >> gl::VertexArray::DIRTY_BIT_ATTRIB_0));

    gl::AttributesMask previousStreamingVertexAttribsMask = mStreamingVertexAttribsMask;

    // Tracks which attribute needs full update
    gl::AttributesMask fullAttribUpdate;

    // Fold DIRTY_BIT_BINDING_n into DIRTY_BIT_ATTRIB_n
    if (bufferBindingDirtyBits.any())
    {
        for (size_t bindingIndex : bufferBindingDirtyBits)
        {
            attribDirtyBits |= bindings[bindingIndex].getBoundAttributesMask();

            gl::VertexArray::DirtyBindingBits dirtyBindingBitsRequirePipelineUpdate =
                (*bindingBits)[bindingIndex] & mBindingDirtyBitsRequiresPipelineUpdate;
            if (dirtyBindingBitsRequirePipelineUpdate.any())
            {
                fullAttribUpdate |= bindings[bindingIndex].getBoundAttributesMask();
            }

            mDivisorExceedMaxSupportedValueBindingMask.set(
                bindingIndex,
                bindings[bindingIndex].getDivisor() > renderer->getMaxVertexAttribDivisor());
        }
    }

    bool elementBufferDirty = dirtyBits[gl::VertexArray::DIRTY_BIT_ELEMENT_ARRAY_BUFFER] ||
                              dirtyBits[gl::VertexArray::DIRTY_BIT_ELEMENT_ARRAY_BUFFER_DATA];
    if (elementBufferDirty)
    {
        gl::Buffer *bufferGL = getElementArrayBuffer();
        if (bufferGL && bufferGL->getSize() > 0)
        {
            // Note that just updating buffer data may still result in a new
            // vk::BufferHelper allocation.
            updateCurrentElementArrayBuffer();
        }
        else
        {
            mCurrentElementArrayBuffer = nullptr;
        }

        mLineLoopBufferFirstIndex.reset();
        mLineLoopBufferLastIndex.reset();
        ANGLE_TRY(contextVk->onIndexBufferChange(mCurrentElementArrayBuffer));
        mDirtyLineLoopTranslation = true;
    }

    // Update mStreamingVertexAttribsMask
    mStreamingVertexAttribsMask = mState.getClientMemoryAttribsMask();
    if (ANGLE_UNLIKELY(mDivisorExceedMaxSupportedValueBindingMask.any()))
    {
        for (size_t bindingIndex : mDivisorExceedMaxSupportedValueBindingMask)
        {
            mStreamingVertexAttribsMask |= bindings[bindingIndex].getBoundAttributesMask();
        }
    }
    mStreamingVertexAttribsMask &= mState.getEnabledAttributesMask();

    // If we sre switching between streaming and buffer mode, set bufferOnly to false since we
    // are actually changing the buffer.
    fullAttribUpdate |= previousStreamingVertexAttribsMask ^ mStreamingVertexAttribsMask;

    // Sync all enabled attributes that are dirty
    gl::AttributesMask enabledAttribDirtyBits = attribDirtyBits & mState.getEnabledAttributesMask();
    for (size_t attribIndex : enabledAttribDirtyBits)
    {
        gl::VertexArray::DirtyAttribBits dirtyAttribBitsRequiresPipelineUpdate =
            (*attribBits)[attribIndex] & mAttribDirtyBitsRequiresPipelineUpdate;

        const bool bufferOnly =
            !fullAttribUpdate[attribIndex] && dirtyAttribBitsRequiresPipelineUpdate.none();

        // This will also update mNeedsConversionAttribMask
        ANGLE_TRY(syncDirtyEnabledAttrib(contextVk, attribs[attribIndex],
                                         bindings[attribs[attribIndex].bindingIndex], attribIndex,
                                         bufferOnly));
    }

    // Sync all enabled attributes that needs data conversion.
    if (ANGLE_UNLIKELY(mNeedsConversionAttribMask.any()))
    {
        // Update mContentsObserverBindingsMask
        mContentsObserverBindingsMask.reset();
        mContentsObserverBindingsMask.set(gl::kElementArrayBufferIndex);
        for (size_t attribIndex : mNeedsConversionAttribMask)
        {
            mContentsObserverBindingsMask.set(attribs[attribIndex].bindingIndex);
        }

        // As long as attribute has changed or data has changed, we need to reprocess it.
        gl::AttributesMask needsConversionAttribDirtyBits = attribDirtyBits;
        for (size_t bindingIndex : bufferDataDirtyBits)
        {
            needsConversionAttribDirtyBits |= bindings[bindingIndex].getBoundAttributesMask();
        }

        needsConversionAttribDirtyBits &= mNeedsConversionAttribMask;
        needsConversionAttribDirtyBits &= mState.getEnabledAttributesMask();

        for (size_t attribIndex : needsConversionAttribDirtyBits)
        {
            ANGLE_TRY(syncNeedsConversionAttrib(contextVk, attribs[attribIndex],
                                                bindings[attribs[attribIndex].bindingIndex],
                                                attribIndex));
        }
    }

    // Sync all disabled attributes that are dirty. We only need to handle attributes that was
    // changed from enabled to disabled.
    const gl::AttributesMask previouslyEnabledAttribDirtyBits =
        mCurrentEnabledAttributesMask & ~mState.getEnabledAttributesMask();
    const gl::AttributesMask disabledAttribDirtyBits =
        previouslyEnabledAttribDirtyBits & attribDirtyBits;
    for (size_t attribIndex : disabledAttribDirtyBits)
    {
        ANGLE_TRY(syncDirtyDisabledAttrib(contextVk, attribs[attribIndex], attribIndex));
    }

    ANGLE_TRY(contextVk->onVertexArrayChange(enabledAttribDirtyBits));

    attribBits->fill(gl::VertexArray::DirtyAttribBits());
    bindingBits->fill(gl::VertexArray::DirtyBindingBits());

    return angle::Result::Continue;
}

ANGLE_INLINE void VertexArrayVk::setDefaultPackedInput(ContextVk *contextVk,
                                                       size_t attribIndex,
                                                       angle::FormatID *formatOut)
{
    const gl::State &glState = contextVk->getState();
    const gl::VertexAttribCurrentValueData &defaultValue =
        glState.getVertexAttribCurrentValues()[attribIndex];

    *formatOut = GetCurrentValueFormatID(defaultValue.Type);
}

angle::Result VertexArrayVk::updateActiveAttribInfo(ContextVk *contextVk)
{
    const std::vector<gl::VertexAttribute> &attribs = mState.getVertexAttributes();
    const std::vector<gl::VertexBinding> &bindings  = mState.getVertexBindings();

    // Update pipeline cache with current active attribute info
    for (size_t attribIndex : mState.getEnabledAttributesMask())
    {
        const gl::VertexAttribute &attrib = attribs[attribIndex];
        const gl::VertexBinding &binding  = bindings[attribs[attribIndex].bindingIndex];
        const angle::FormatID format      = attrib.format->id;

        ANGLE_TRY(contextVk->onVertexAttributeChange(
            attribIndex, getCurrentArrayBufferStride(attribIndex), binding.getDivisor(), format,
            getCurrentArrayBufferRelativeOffset(attribIndex), mCurrentArrayBuffers[attribIndex]));

        mCurrentArrayBufferFormats[attribIndex] = format;
    }

    return angle::Result::Continue;
}

angle::Result VertexArrayVk::syncDirtyEnabledAttrib(ContextVk *contextVk,
                                                    const gl::VertexAttribute &attrib,
                                                    const gl::VertexBinding &binding,
                                                    size_t attribIndex,
                                                    bool bufferOnly)
{
    vk::Renderer *renderer = contextVk->getRenderer();
    ASSERT(attrib.enabled);

    const vk::Format &vertexFormat = renderer->getFormat(attrib.format->id);

    // Init attribute offset to the front-end value
    mVertexInputAttribDesc[attribIndex].offset      = attrib.relativeOffset;
    gl::Buffer *bufferGL                            = getVertexArrayBuffer(attrib.bindingIndex);
    bool isStreamingVertexAttrib                    = mStreamingVertexAttribsMask.test(attribIndex);

    mNeedsConversionAttribMask.reset(attribIndex);

    if (!isStreamingVertexAttrib && bufferGL->getSize() > 0)
    {
        BufferVk *bufferVk             = vk::GetImpl(bufferGL);
        const angle::Format &srcFormat = vertexFormat.getIntendedFormat();
        unsigned srcFormatSize         = srcFormat.pixelBytes;
        uint32_t srcStride       = binding.getStride() == 0 ? srcFormatSize : binding.getStride();
        bool hasAtLeastOneVertex = (bufferGL->getSize() - binding.getOffset()) >= srcFormatSize;
        bool bindingIsAligned =
            BindingIsAligned(srcFormat, binding.getOffset() + attrib.relativeOffset, srcStride);

        bool needsConversion =
            hasAtLeastOneVertex &&
            (vertexFormat.getVertexLoadRequiresConversion() || !bindingIsAligned);

        if (ANGLE_UNLIKELY(needsConversion))
        {
            // Early out if needs conversion. We will handle these attributes last.
            mNeedsConversionAttribMask.set(attribIndex);
            return angle::Result::Continue;
        }
        else if (ANGLE_LIKELY(hasAtLeastOneVertex))
        {
            vk::BufferHelper &bufferHelper         = bufferVk->getBuffer();
            mCurrentArrayBuffers[attribIndex]      = &bufferHelper;
            mCurrentArrayBufferSerial[attribIndex] = bufferHelper.getBufferSerial();
            VkDeviceSize bufferOffset;
            mCurrentArrayBufferHandles[attribIndex] =
                bufferHelper.getBufferForVertexArray(contextVk, bufferVk->getSize(), &bufferOffset)
                    .getHandle();

            // Vulkan requires the offset is within the buffer. We use robust access
            // behaviour to reset the offset if it starts outside the buffer.
            mCurrentArrayBufferOffsets[attribIndex] =
                binding.getOffset() < static_cast<GLint64>(bufferVk->getSize())
                    ? binding.getOffset() + bufferOffset
                    : bufferOffset;

            mVertexInputBindingDesc[attribIndex].stride = binding.getStride();
        }
        else
        {
            vk::BufferHelper &emptyBuffer = contextVk->getEmptyBuffer();

            mCurrentArrayBuffers[attribIndex]       = &emptyBuffer;
            mCurrentArrayBufferSerial[attribIndex]  = emptyBuffer.getBufferSerial();
            mCurrentArrayBufferHandles[attribIndex] = emptyBuffer.getBuffer().getHandle();
            mCurrentArrayBufferOffsets[attribIndex] = emptyBuffer.getOffset();
            mVertexInputBindingDesc[attribIndex].stride = 0;
        }
    }
    else
    {
        vk::BufferHelper &emptyBuffer           = contextVk->getEmptyBuffer();
        mCurrentArrayBuffers[attribIndex]       = &emptyBuffer;
        mCurrentArrayBufferSerial[attribIndex]  = emptyBuffer.getBufferSerial();
        mCurrentArrayBufferHandles[attribIndex] = emptyBuffer.getBuffer().getHandle();
        mCurrentArrayBufferOffsets[attribIndex] = emptyBuffer.getOffset();

        if (isStreamingVertexAttrib)
        {
            bool combined = ShouldCombineAttributes(renderer, attrib, binding);
            mVertexInputBindingDesc[attribIndex].stride =
                combined ? binding.getStride() : vertexFormat.getActualBufferFormat().pixelBytes;
        }
        else
        {
            mVertexInputBindingDesc[attribIndex].stride = 0;
        }
    }

    if (!bufferOnly)
    {
        mCurrentArrayBufferFormats[attribIndex]  = attrib.format->id;
        mVertexInputBindingDesc[attribIndex].divisor = binding.getDivisor();
    }

    mCurrentEnabledAttributesMask.set(attribIndex);
    return angle::Result::Continue;
}

angle::Result VertexArrayVk::syncDirtyDisabledAttrib(ContextVk *contextVk,
                                                     const gl::VertexAttribute &attrib,
                                                     size_t attribIndex)
{
    ASSERT(!attrib.enabled);
    ASSERT(mCurrentEnabledAttributesMask.test(attribIndex));
    contextVk->invalidateDefaultAttribute(attribIndex);

    // These will be filled out by the ContextVk.
    vk::BufferHelper &emptyBuffer                   = contextVk->getEmptyBuffer();
    mCurrentArrayBuffers[attribIndex]               = &emptyBuffer;
    mCurrentArrayBufferSerial[attribIndex]          = emptyBuffer.getBufferSerial();
    mCurrentArrayBufferHandles[attribIndex]         = emptyBuffer.getBuffer().getHandle();
    mCurrentArrayBufferOffsets[attribIndex]         = emptyBuffer.getOffset();
    mVertexInputBindingDesc[attribIndex].stride     = 0;
    mVertexInputBindingDesc[attribIndex].divisor    = 0;
    mVertexInputAttribDesc[attribIndex].offset      = 0;

    mCurrentEnabledAttributesMask.reset(attribIndex);
    return angle::Result::Continue;
}

angle::Result VertexArrayVk::syncNeedsConversionAttrib(ContextVk *contextVk,
                                                       const gl::VertexAttribute &attrib,
                                                       const gl::VertexBinding &binding,
                                                       size_t attribIndex)
{
    vk::Renderer *renderer = contextVk->getRenderer();
    ASSERT(attrib.enabled);
    ASSERT(mNeedsConversionAttribMask.test(attribIndex));
    ASSERT(!mStreamingVertexAttribsMask.test(attribIndex));
    ASSERT(mVertexInputAttribDesc[attribIndex].offset == attrib.relativeOffset);
    ASSERT(mContentsObserverBindingsMask.test(attrib.bindingIndex));

    const vk::Format &vertexFormat = renderer->getFormat(attrib.format->id);

    gl::Buffer *bufferGL = getVertexArrayBuffer(attrib.bindingIndex);
    ASSERT(bufferGL);
    ASSERT(bufferGL->getSize() > 0);
    BufferVk *bufferVk = vk::GetImpl(bufferGL);

    const angle::Format &srcFormat = vertexFormat.getIntendedFormat();
    unsigned srcFormatSize         = srcFormat.pixelBytes;
    uint32_t srcStride             = binding.getStride() == 0 ? srcFormatSize : binding.getStride();
    bool bindingIsAligned =
        BindingIsAligned(srcFormat, binding.getOffset() + attrib.relativeOffset, srcStride);

    const angle::Format &dstFormat = vertexFormat.getActualBufferFormat();
    // Converted buffer is tightly packed
    uint32_t dstStride = dstFormat.pixelBytes;

    ASSERT(vertexFormat.getVertexInputAlignment() <= vk::kVertexBufferAlignment);

    WarnOnVertexFormatConversion(contextVk, vertexFormat);

    const VertexConversionBuffer::CacheKey cacheKey{
        srcFormat.id, srcStride, static_cast<size_t>(binding.getOffset()) + attrib.relativeOffset,
        !bindingIsAligned, false};

    VertexConversionBuffer *conversion = bufferVk->getVertexConversionBuffer(renderer, cacheKey);

    // Converted attribs are packed in their own VK buffer so offset is relative to the
    // binding and coversion's offset. The conversion buffer try to reuse the existing
    // buffer as much as possible to reduce the amount of data that has to be converted.
    // When binding's offset changes, it will check if new offset and existing buffer's
    // offset are multiple of strides apart. It yes it will reuse. If new offset is
    // larger, all existing data are still valid. If the new offset is smaller it will
    // mark the newly exposed range dirty and then rely on
    // ContextVk::initBufferForVertexConversion to decide buffer's size is big enough or
    // not and reallocate (and mark entire buffer dirty) if needed.
    //
    // bufferVk:-----------------------------------------------------------------------
    //                 |                   |
    //                 |                bingding.offset + attrib.relativeOffset.
    //          conversion->getCacheKey().offset
    //
    // conversion.buffer: --------------------------------------------------------------
    //                                     |
    //                                   dstRelativeOffset
    size_t srcRelativeOffset =
        binding.getOffset() + attrib.relativeOffset - conversion->getCacheKey().offset;
    size_t numberOfVerticesToSkip = srcRelativeOffset / srcStride;
    size_t dstRelativeOffset      = numberOfVerticesToSkip * dstStride;

    if (conversion->dirty())
    {
        if (bindingIsAligned)
        {
            ANGLE_TRY(
                convertVertexBufferGPU(contextVk, bufferVk, conversion, srcFormat, dstFormat));
        }
        else
        {
            ANGLE_VK_PERF_WARNING(contextVk, GL_DEBUG_SEVERITY_HIGH,
                                  "GPU stall due to vertex format conversion of unaligned data");

            ANGLE_TRY(convertVertexBufferCPU(contextVk, bufferVk, conversion, srcFormat, dstFormat,
                                             vertexFormat.getVertexLoadFunction()));
        }

        // If conversion happens, the destination buffer stride may be changed,
        // therefore an attribute change needs to be called. Note that it may trigger
        // unnecessary vulkan PSO update when the destination buffer stride does not
        // change, but for simplicity just make it conservative
    }

    vk::BufferHelper *bufferHelper         = conversion->getBuffer();
    mCurrentArrayBuffers[attribIndex]      = bufferHelper;
    mCurrentArrayBufferSerial[attribIndex] = bufferHelper->getBufferSerial();
    VkDeviceSize bufferOffset;
    mCurrentArrayBufferHandles[attribIndex] =
        bufferHelper->getBufferForVertexArray(contextVk, bufferHelper->getSize(), &bufferOffset)
            .getHandle();
    ASSERT(BindingIsAligned(dstFormat, bufferOffset + dstRelativeOffset, dstStride));
    mCurrentArrayBufferOffsets[attribIndex]         = bufferOffset + dstRelativeOffset;
    mVertexInputAttribDesc[attribIndex].offset      = 0;
    mVertexInputBindingDesc[attribIndex].stride     = dstStride;

    mCurrentArrayBufferFormats[attribIndex]  = attrib.format->id;
    mVertexInputBindingDesc[attribIndex].divisor = binding.getDivisor();

    mCurrentEnabledAttributesMask.set(attribIndex);
    return angle::Result::Continue;
}

gl::AttributesMask VertexArrayVk::mergeClientAttribsRange(
    vk::Renderer *renderer,
    const gl::AttributesMask activeStreamedAttribs,
    size_t startVertex,
    size_t endVertex,
    std::array<AttributeRange, gl::MAX_VERTEX_ATTRIBS> &mergeRangesOut,
    std::array<size_t, gl::MAX_VERTEX_ATTRIBS> &mergedIndexesOut) const
{
    const std::vector<gl::VertexAttribute> &attribs = mState.getVertexAttributes();
    const std::vector<gl::VertexBinding> &bindings  = mState.getVertexBindings();
    gl::AttributesMask attributeMaskCanCombine;
    angle::FixedVector<size_t, gl::MAX_VERTEX_ATTRIBS> combinedIndexes;
    for (size_t attribIndex : activeStreamedAttribs)
    {
        const gl::VertexAttribute &attrib = attribs[attribIndex];
        ASSERT(attrib.enabled);
        const gl::VertexBinding &binding = bindings[attrib.bindingIndex];
        const vk::Format &vertexFormat   = renderer->getFormat(attrib.format->id);
        bool combined                    = ShouldCombineAttributes(renderer, attrib, binding);
        attributeMaskCanCombine.set(attribIndex, combined);
        if (combined)
        {
            combinedIndexes.push_back(attribIndex);
        }
        GLuint pixelBytes                     = vertexFormat.getActualBufferFormat().pixelBytes;
        size_t destStride      = combined ? binding.getStride() : pixelBytes;
        uintptr_t startAddress = reinterpret_cast<uintptr_t>(attrib.pointer);
        mergeRangesOut[attribIndex].startAddr = startAddress;
        mergeRangesOut[attribIndex].endAddr =
            startAddress + (endVertex - 1) * destStride + pixelBytes;
        mergeRangesOut[attribIndex].copyStartAddr =
            startAddress + startVertex * binding.getStride();
        mergedIndexesOut[attribIndex] = attribIndex;
    }
    if (attributeMaskCanCombine.none())
    {
        return attributeMaskCanCombine;
    }
    auto comp = [&mergeRangesOut](size_t a, size_t b) -> bool {
        return mergeRangesOut[a] < mergeRangesOut[b];
    };
    // Only sort combined range indexes.
    std::sort(combinedIndexes.begin(), combinedIndexes.end(), comp);
    // Merge combined range span.
    auto next = combinedIndexes.begin();
    auto cur  = next++;
    while (next != combinedIndexes.end() || (cur != next))
    {
        // Cur and next overlaps: merge next into cur and move next.
        if (next != combinedIndexes.end() &&
            mergeRangesOut[*cur].endAddr >= mergeRangesOut[*next].startAddr)
        {
            mergeRangesOut[*cur].endAddr =
                std::max(mergeRangesOut[*cur].endAddr, mergeRangesOut[*next].endAddr);
            mergeRangesOut[*cur].copyStartAddr =
                std::min(mergeRangesOut[*cur].copyStartAddr, mergeRangesOut[*next].copyStartAddr);
            mergedIndexesOut[*next] = mergedIndexesOut[*cur];
            ++next;
        }
        else
        {
            ++cur;
            if (cur != next)
            {
                mergeRangesOut[*cur] = mergeRangesOut[*(cur - 1)];
            }
            else if (next != combinedIndexes.end())
            {
                ++next;
            }
        }
    }
    return attributeMaskCanCombine;
}

// Handle copying client attribs and/or expanding attrib buffer in case where attribute
// divisor value has to be emulated.
angle::Result VertexArrayVk::updateStreamedAttribs(const gl::Context *context,
                                                   GLint firstVertex,
                                                   GLsizei vertexOrIndexCount,
                                                   GLsizei instanceCount,
                                                   gl::DrawElementsType indexTypeOrInvalid,
                                                   const void *indices)
{
    ContextVk *contextVk   = vk::GetImpl(context);
    vk::Renderer *renderer = contextVk->getRenderer();

    const gl::AttributesMask activeAttribs =
        context->getActiveClientAttribsMask() | context->getActiveBufferedAttribsMask();
    const gl::AttributesMask activeStreamedAttribs = mStreamingVertexAttribsMask & activeAttribs;

    // Early return for corner case where emulated buffered attribs are not active
    if (!activeStreamedAttribs.any())
    {
        return angle::Result::Continue;
    }

    GLint startVertex;
    size_t vertexCount;
    ANGLE_TRY(GetVertexRangeInfo(context, firstVertex, vertexOrIndexCount, indexTypeOrInvalid,
                                 indices, 0, &startVertex, &vertexCount));

    ASSERT(vertexCount > 0);
    const auto &attribs  = mState.getVertexAttributes();
    const auto &bindings = mState.getVertexBindings();

    std::array<size_t, gl::MAX_VERTEX_ATTRIBS> mergedIndexes;
    std::array<AttributeRange, gl::MAX_VERTEX_ATTRIBS> mergeRanges;
    std::array<vk::BufferHelper *, gl::MAX_VERTEX_ATTRIBS> attribBufferHelper = {};
    auto mergeAttribMask =
        mergeClientAttribsRange(renderer, activeStreamedAttribs, startVertex,
                                startVertex + vertexCount, mergeRanges, mergedIndexes);

    for (size_t attribIndex : activeStreamedAttribs)
    {
        const gl::VertexAttribute &attrib = attribs[attribIndex];
        ASSERT(attrib.enabled);
        const gl::VertexBinding &binding = bindings[attrib.bindingIndex];

        const vk::Format &vertexFormat = renderer->getFormat(attrib.format->id);
        const angle::Format &dstFormat = vertexFormat.getActualBufferFormat();
        GLuint pixelBytes              = dstFormat.pixelBytes;

        ASSERT(vertexFormat.getVertexInputAlignment() <= vk::kVertexBufferAlignment);

        vk::BufferHelper *vertexDataBuffer = nullptr;
        const uint8_t *src                 = static_cast<const uint8_t *>(attrib.pointer);
        const uint32_t divisor             = binding.getDivisor();

        bool combined            = mergeAttribMask.test(attribIndex);
        GLuint stride            = combined ? binding.getStride() : pixelBytes;
        VkDeviceSize startOffset = 0;
        if (divisor > 0)
        {
            // Instanced attrib
            if (divisor > renderer->getMaxVertexAttribDivisor())
            {
                // Divisor will be set to 1 & so update buffer to have 1 attrib per instance
                size_t bytesToAllocate = instanceCount * stride;

                // Allocate buffer for results
                ANGLE_TRY(contextVk->allocateStreamedVertexBuffer(attribIndex, bytesToAllocate,
                                                                  &vertexDataBuffer));

                gl::Buffer *bufferGL = getVertexArrayBuffer(attrib.bindingIndex);
                if (bufferGL != nullptr)
                {
                    // Only do the data copy if src buffer is valid.
                    if (bufferGL->getSize() > 0)
                    {
                        // Map buffer to expand attribs for divisor emulation
                        BufferVk *bufferVk = vk::GetImpl(bufferGL);
                        void *buffSrc      = nullptr;
                        ANGLE_TRY(bufferVk->mapForReadAccessOnly(contextVk, &buffSrc));
                        src = reinterpret_cast<const uint8_t *>(buffSrc) + binding.getOffset();

                        uint32_t srcAttributeSize =
                            static_cast<uint32_t>(ComputeVertexAttributeTypeSize(attrib));

                        size_t numVertices = GetVertexCount(bufferVk, binding, srcAttributeSize);

                        ANGLE_TRY(StreamVertexDataWithDivisor(
                            contextVk, vertexDataBuffer, src, bytesToAllocate, binding.getStride(),
                            stride, vertexFormat.getVertexLoadFunction(), divisor, numVertices));

                        ANGLE_TRY(bufferVk->unmapReadAccessOnly(contextVk));
                    }
                    else if (contextVk->getExtensions().robustnessAny())
                    {
                        // Satisfy robustness constraints (only if extension enabled)
                        uint8_t *dst = vertexDataBuffer->getMappedMemory();
                        memset(dst, 0, bytesToAllocate);
                    }
                }
                else
                {
                    size_t numVertices = instanceCount;
                    ANGLE_TRY(StreamVertexDataWithDivisor(
                        contextVk, vertexDataBuffer, src, bytesToAllocate, binding.getStride(),
                        stride, vertexFormat.getVertexLoadFunction(), divisor, numVertices));
                }
            }
            else
            {
                ASSERT(getVertexArrayBuffer(attrib.bindingIndex) == nullptr);
                size_t count           = UnsignedCeilDivide(instanceCount, divisor);
                size_t bytesToAllocate = count * stride;

                // Allocate buffer for results
                ANGLE_TRY(contextVk->allocateStreamedVertexBuffer(attribIndex, bytesToAllocate,
                                                                  &vertexDataBuffer));

                ANGLE_TRY(StreamVertexData(contextVk, vertexDataBuffer, src, bytesToAllocate, 0,
                                           count, binding.getStride(),
                                           vertexFormat.getVertexLoadFunction()));
            }
        }
        else if (attrib.pointer == nullptr)
        {
            // Set them to the initial value.
            vk::BufferHelper &emptyBuffer            = contextVk->getEmptyBuffer();
            mCurrentArrayBuffers[attribIndex]        = &emptyBuffer;
            mCurrentArrayBufferHandles[attribIndex]  = emptyBuffer.getBuffer().getHandle();
            mCurrentArrayBufferOffsets[attribIndex]  = 0;
            mVertexInputBindingDesc[attribIndex].stride  = 0;
            mVertexInputBindingDesc[attribIndex].divisor = 0;
            continue;
        }
        else
        {
            ASSERT(getVertexArrayBuffer(attrib.bindingIndex) == nullptr);
            size_t mergedAttribIdx      = mergedIndexes[attribIndex];
            const AttributeRange &range = mergeRanges[attribIndex];
            if (attribBufferHelper[mergedAttribIdx] == nullptr)
            {
                size_t destOffset =
                    combined ? range.copyStartAddr - range.startAddr : startVertex * stride;
                size_t bytesToAllocate = range.endAddr - range.startAddr;
                ANGLE_TRY(contextVk->allocateStreamedVertexBuffer(
                    mergedAttribIdx, bytesToAllocate, &attribBufferHelper[mergedAttribIdx]));
                ANGLE_TRY(StreamVertexData(
                    contextVk, attribBufferHelper[mergedAttribIdx],
                    (const uint8_t *)range.copyStartAddr, bytesToAllocate - destOffset, destOffset,
                    vertexCount, binding.getStride(),
                    combined ? nullptr : vertexFormat.getVertexLoadFunction()));
            }
            vertexDataBuffer = attribBufferHelper[mergedAttribIdx];
            startOffset      = combined ? (uintptr_t)attrib.pointer - range.startAddr : 0;
        }
        ASSERT(vertexDataBuffer != nullptr);
        mCurrentArrayBuffers[attribIndex]      = vertexDataBuffer;
        mCurrentArrayBufferSerial[attribIndex] = vertexDataBuffer->getBufferSerial();
        VkDeviceSize bufferOffset;
        mCurrentArrayBufferHandles[attribIndex] =
            vertexDataBuffer
                ->getBufferForVertexArray(contextVk, vertexDataBuffer->getSize(), &bufferOffset)
                .getHandle();
        mCurrentArrayBufferOffsets[attribIndex]  = bufferOffset + startOffset;
        mVertexInputBindingDesc[attribIndex].stride  = stride;
        mVertexInputBindingDesc[attribIndex].divisor = divisor;
        ASSERT(BindingIsAligned(dstFormat, mCurrentArrayBufferOffsets[attribIndex],
                                mVertexInputBindingDesc[attribIndex].stride));
    }

    return angle::Result::Continue;
}

angle::Result VertexArrayVk::handleLineLoop(ContextVk *contextVk,
                                            GLint firstVertex,
                                            GLsizei vertexOrIndexCount,
                                            gl::DrawElementsType indexTypeOrInvalid,
                                            const void *indices,
                                            vk::BufferHelper **indexBufferOut,
                                            uint32_t *indexCountOut)
{
    if (indexTypeOrInvalid != gl::DrawElementsType::InvalidEnum)
    {
        // Handle GL_LINE_LOOP drawElements.
        if (mDirtyLineLoopTranslation)
        {
            gl::Buffer *elementArrayBuffer = getElementArrayBuffer();

            if (!elementArrayBuffer)
            {
                ANGLE_TRY(mLineLoopHelper.streamIndices(
                    contextVk, indexTypeOrInvalid, vertexOrIndexCount,
                    reinterpret_cast<const uint8_t *>(indices), indexBufferOut, indexCountOut));
            }
            else
            {
                // When using an element array buffer, 'indices' is an offset to the first element.
                intptr_t offset                = reinterpret_cast<intptr_t>(indices);
                BufferVk *elementArrayBufferVk = vk::GetImpl(elementArrayBuffer);
                ANGLE_TRY(mLineLoopHelper.getIndexBufferForElementArrayBuffer(
                    contextVk, elementArrayBufferVk, indexTypeOrInvalid, vertexOrIndexCount, offset,
                    indexBufferOut, indexCountOut));
            }
        }

        // If we've had a drawArrays call with a line loop before, we want to make sure this is
        // invalidated the next time drawArrays is called since we use the same index buffer for
        // both calls.
        mLineLoopBufferFirstIndex.reset();
        mLineLoopBufferLastIndex.reset();
        return angle::Result::Continue;
    }

    // Note: Vertex indexes can be arbitrarily large.
    uint32_t clampedVertexCount = gl::clampCast<uint32_t>(vertexOrIndexCount);

    // Handle GL_LINE_LOOP drawArrays.
    size_t lastVertex = static_cast<size_t>(firstVertex + clampedVertexCount);
    if (!mLineLoopBufferFirstIndex.valid() || !mLineLoopBufferLastIndex.valid() ||
        mLineLoopBufferFirstIndex != firstVertex || mLineLoopBufferLastIndex != lastVertex)
    {
        ANGLE_TRY(mLineLoopHelper.getIndexBufferForDrawArrays(contextVk, clampedVertexCount,
                                                              firstVertex, indexBufferOut));

        mLineLoopBufferFirstIndex = firstVertex;
        mLineLoopBufferLastIndex  = lastVertex;
    }
    else
    {
        *indexBufferOut = mLineLoopHelper.getCurrentIndexBuffer();
    }
    *indexCountOut = vertexOrIndexCount + 1;

    return angle::Result::Continue;
}

angle::Result VertexArrayVk::updateDefaultAttrib(ContextVk *contextVk, size_t attribIndex)
{
    if (!mState.getEnabledAttributesMask().test(attribIndex))
    {
        vk::BufferHelper *bufferHelper;
        ANGLE_TRY(
            contextVk->allocateStreamedVertexBuffer(attribIndex, kDefaultValueSize, &bufferHelper));

        const gl::VertexAttribCurrentValueData &defaultValue =
            contextVk->getState().getVertexAttribCurrentValues()[attribIndex];
        uint8_t *ptr = bufferHelper->getMappedMemory();
        memcpy(ptr, &defaultValue.Values, kDefaultValueSize);
        ANGLE_TRY(bufferHelper->flush(contextVk->getRenderer()));

        VkDeviceSize bufferOffset;
        mCurrentArrayBufferHandles[attribIndex] =
            bufferHelper->getBufferForVertexArray(contextVk, kDefaultValueSize, &bufferOffset)
                .getHandle();
        mCurrentArrayBufferOffsets[attribIndex]  = bufferOffset;
        mCurrentArrayBuffers[attribIndex]        = bufferHelper;
        mCurrentArrayBufferSerial[attribIndex]   = bufferHelper->getBufferSerial();
        mVertexInputBindingDesc[attribIndex].stride  = 0;
        mVertexInputBindingDesc[attribIndex].divisor = 0;

        setDefaultPackedInput(contextVk, attribIndex, &mCurrentArrayBufferFormats[attribIndex]);

        ANGLE_TRY(contextVk->onVertexAttributeChange(
            attribIndex, 0, 0, mCurrentArrayBufferFormats[attribIndex], 0, nullptr));
    }

    return angle::Result::Continue;
}
}  // namespace rx