angletypes.cpp

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Author : Shahbaz Youssefi
Date : 2020-07-21 10:18:41
Hash : c757e607
Message : Vulkan: Fix deferred clears and noop clear and blit Imagine the following situation: 1. Clear draw framebuffer 2. Noop operation on the framebuffer (Clear, ClearBuffer, BlitFramebuffer with flags specifying non-existing attachments) 3. Change framebuffer's attachment 4. Draw into framebuffer At step 2, FramebufferVk::syncState was called before noop-ing the operation. During syncState, deferred clears were stored in the framebuffer and weren't flushed because the actual operation was not performed. At step 4, the deferred clear meant for the prior attachment gets applied to the new attachment. Bug: angleproject:4865 Change-Id: I5b096bacf00356b4dccd4cbc9561b87b1bb557d8 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2309224 Reviewed-by: Tim Van Patten <timvp@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
src/libANGLE/angletypes.cpp
//
// Copyright 2013 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.
//

// angletypes.h : Defines a variety of structures and enum types that are used throughout libGLESv2

#include "libANGLE/angletypes.h"
#include "libANGLE/Program.h"
#include "libANGLE/State.h"
#include "libANGLE/VertexArray.h"
#include "libANGLE/VertexAttribute.h"

namespace gl
{
RasterizerState::RasterizerState()
{
    memset(this, 0, sizeof(RasterizerState));

    rasterizerDiscard   = false;
    cullFace            = false;
    cullMode            = CullFaceMode::Back;
    frontFace           = GL_CCW;
    polygonOffsetFill   = false;
    polygonOffsetFactor = 0.0f;
    polygonOffsetUnits  = 0.0f;
    pointDrawMode       = false;
    multiSample         = false;
    dither              = true;
}

RasterizerState::RasterizerState(const RasterizerState &other)
{
    memcpy(this, &other, sizeof(RasterizerState));
}

bool operator==(const RasterizerState &a, const RasterizerState &b)
{
    return memcmp(&a, &b, sizeof(RasterizerState)) == 0;
}

bool operator!=(const RasterizerState &a, const RasterizerState &b)
{
    return !(a == b);
}

BlendState::BlendState()
{
    memset(this, 0, sizeof(BlendState));

    blend              = false;
    sourceBlendRGB     = GL_ONE;
    sourceBlendAlpha   = GL_ONE;
    destBlendRGB       = GL_ZERO;
    destBlendAlpha     = GL_ZERO;
    blendEquationRGB   = GL_FUNC_ADD;
    blendEquationAlpha = GL_FUNC_ADD;
    colorMaskRed       = true;
    colorMaskGreen     = true;
    colorMaskBlue      = true;
    colorMaskAlpha     = true;
}

BlendState::BlendState(const BlendState &other)
{
    memcpy(this, &other, sizeof(BlendState));
}

bool operator==(const BlendState &a, const BlendState &b)
{
    return memcmp(&a, &b, sizeof(BlendState)) == 0;
}

bool operator!=(const BlendState &a, const BlendState &b)
{
    return !(a == b);
}

DepthStencilState::DepthStencilState()
{
    memset(this, 0, sizeof(DepthStencilState));

    depthTest                = false;
    depthFunc                = GL_LESS;
    depthMask                = true;
    stencilTest              = false;
    stencilFunc              = GL_ALWAYS;
    stencilMask              = static_cast<GLuint>(-1);
    stencilWritemask         = static_cast<GLuint>(-1);
    stencilBackFunc          = GL_ALWAYS;
    stencilBackMask          = static_cast<GLuint>(-1);
    stencilBackWritemask     = static_cast<GLuint>(-1);
    stencilFail              = GL_KEEP;
    stencilPassDepthFail     = GL_KEEP;
    stencilPassDepthPass     = GL_KEEP;
    stencilBackFail          = GL_KEEP;
    stencilBackPassDepthFail = GL_KEEP;
    stencilBackPassDepthPass = GL_KEEP;
}

DepthStencilState::DepthStencilState(const DepthStencilState &other)
{
    memcpy(this, &other, sizeof(DepthStencilState));
}

bool DepthStencilState::isDepthMaskedOut() const
{
    return !depthMask;
}

bool DepthStencilState::isStencilMaskedOut() const
{
    return (stencilMask & stencilWritemask) == 0;
}

bool operator==(const DepthStencilState &a, const DepthStencilState &b)
{
    return memcmp(&a, &b, sizeof(DepthStencilState)) == 0;
}

bool operator!=(const DepthStencilState &a, const DepthStencilState &b)
{
    return !(a == b);
}

SamplerState::SamplerState()
{
    memset(this, 0, sizeof(SamplerState));

    setMinFilter(GL_NEAREST_MIPMAP_LINEAR);
    setMagFilter(GL_LINEAR);
    setWrapS(GL_REPEAT);
    setWrapT(GL_REPEAT);
    setWrapR(GL_REPEAT);
    setMaxAnisotropy(1.0f);
    setMinLod(-1000.0f);
    setMaxLod(1000.0f);
    setCompareMode(GL_NONE);
    setCompareFunc(GL_LEQUAL);
    setSRGBDecode(GL_DECODE_EXT);
}

SamplerState::SamplerState(const SamplerState &other) = default;

// static
SamplerState SamplerState::CreateDefaultForTarget(TextureType type)
{
    SamplerState state;

    // According to OES_EGL_image_external and ARB_texture_rectangle: For external textures, the
    // default min filter is GL_LINEAR and the default s and t wrap modes are GL_CLAMP_TO_EDGE.
    if (type == TextureType::External || type == TextureType::Rectangle)
    {
        state.mMinFilter = GL_LINEAR;
        state.mWrapS     = GL_CLAMP_TO_EDGE;
        state.mWrapT     = GL_CLAMP_TO_EDGE;
    }

    return state;
}

void SamplerState::setMinFilter(GLenum minFilter)
{
    mMinFilter                    = minFilter;
    mCompleteness.typed.minFilter = static_cast<uint8_t>(FromGLenum<FilterMode>(minFilter));
}

void SamplerState::setMagFilter(GLenum magFilter)
{
    mMagFilter                    = magFilter;
    mCompleteness.typed.magFilter = static_cast<uint8_t>(FromGLenum<FilterMode>(magFilter));
}

void SamplerState::setWrapS(GLenum wrapS)
{
    mWrapS                    = wrapS;
    mCompleteness.typed.wrapS = static_cast<uint8_t>(FromGLenum<WrapMode>(wrapS));
}

void SamplerState::setWrapT(GLenum wrapT)
{
    mWrapT = wrapT;
    updateWrapTCompareMode();
}

void SamplerState::setWrapR(GLenum wrapR)
{
    mWrapR = wrapR;
}

void SamplerState::setMaxAnisotropy(float maxAnisotropy)
{
    mMaxAnisotropy = maxAnisotropy;
}

void SamplerState::setMinLod(GLfloat minLod)
{
    mMinLod = minLod;
}

void SamplerState::setMaxLod(GLfloat maxLod)
{
    mMaxLod = maxLod;
}

void SamplerState::setCompareMode(GLenum compareMode)
{
    mCompareMode = compareMode;
    updateWrapTCompareMode();
}

void SamplerState::setCompareFunc(GLenum compareFunc)
{
    mCompareFunc = compareFunc;
}

void SamplerState::setSRGBDecode(GLenum sRGBDecode)
{
    mSRGBDecode = sRGBDecode;
}

void SamplerState::setBorderColor(const ColorGeneric &color)
{
    mBorderColor = color;
}

void SamplerState::updateWrapTCompareMode()
{
    uint8_t wrap    = static_cast<uint8_t>(FromGLenum<WrapMode>(mWrapT));
    uint8_t compare = static_cast<uint8_t>(mCompareMode == GL_NONE ? 0x10 : 0x00);
    mCompleteness.typed.wrapTCompareMode = wrap | compare;
}

ImageUnit::ImageUnit()
    : texture(), level(0), layered(false), layer(0), access(GL_READ_ONLY), format(GL_R32UI)
{}

ImageUnit::ImageUnit(const ImageUnit &other) = default;

ImageUnit::~ImageUnit() = default;

BlendStateExt::BlendStateExt(const size_t drawBuffers)
    : mMaxFactorMask(FactorStorage::GetMask(drawBuffers)),
      mSrcColor(FactorStorage::GetReplicatedValue(BlendFactorType::One, mMaxFactorMask)),
      mDstColor(FactorStorage::GetReplicatedValue(BlendFactorType::Zero, mMaxFactorMask)),
      mSrcAlpha(FactorStorage::GetReplicatedValue(BlendFactorType::One, mMaxFactorMask)),
      mDstAlpha(FactorStorage::GetReplicatedValue(BlendFactorType::Zero, mMaxFactorMask)),
      mMaxEquationMask(EquationStorage::GetMask(drawBuffers)),
      mEquationColor(EquationStorage::GetReplicatedValue(BlendEquationType::Add, mMaxEquationMask)),
      mEquationAlpha(EquationStorage::GetReplicatedValue(BlendEquationType::Add, mMaxEquationMask)),
      mMaxColorMask(ColorMaskStorage::GetMask(drawBuffers)),
      mColorMask(ColorMaskStorage::GetReplicatedValue(PackColorMask(true, true, true, true),
                                                      mMaxColorMask)),
      mMaxEnabledMask(0xFF >> (8 - drawBuffers)),
      mEnabledMask(),
      mMaxDrawBuffers(drawBuffers)
{}

BlendStateExt &BlendStateExt::operator=(const BlendStateExt &other)
{
    memcpy(this, &other, sizeof(BlendStateExt));
    return *this;
}

void BlendStateExt::setEnabled(const bool enabled)
{
    mEnabledMask = enabled ? mMaxEnabledMask : DrawBufferMask::Zero();
}

void BlendStateExt::setEnabledIndexed(const size_t index, const bool enabled)
{
    ASSERT(index < mMaxDrawBuffers);
    mEnabledMask.set(index, enabled);
}

BlendStateExt::ColorMaskStorage::Type BlendStateExt::expandColorMaskValue(const bool red,
                                                                          const bool green,
                                                                          const bool blue,
                                                                          const bool alpha) const
{
    return BlendStateExt::ColorMaskStorage::GetReplicatedValue(
        PackColorMask(red, green, blue, alpha), mMaxColorMask);
}

BlendStateExt::ColorMaskStorage::Type BlendStateExt::expandColorMaskIndexed(
    const size_t index) const
{
    return ColorMaskStorage::GetReplicatedValue(
        ColorMaskStorage::GetValueIndexed(index, mColorMask), mMaxColorMask);
}

void BlendStateExt::setColorMask(const bool red,
                                 const bool green,
                                 const bool blue,
                                 const bool alpha)
{
    mColorMask = expandColorMaskValue(red, green, blue, alpha);
}

void BlendStateExt::setColorMaskIndexed(const size_t index, const uint8_t value)
{
    ASSERT(index < mMaxDrawBuffers);
    ASSERT(value <= 0xF);
    ColorMaskStorage::SetValueIndexed(index, value, &mColorMask);
}

void BlendStateExt::setColorMaskIndexed(const size_t index,
                                        const bool red,
                                        const bool green,
                                        const bool blue,
                                        const bool alpha)
{
    ASSERT(index < mMaxDrawBuffers);
    ColorMaskStorage::SetValueIndexed(index, PackColorMask(red, green, blue, alpha), &mColorMask);
}

uint8_t BlendStateExt::getColorMaskIndexed(const size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return ColorMaskStorage::GetValueIndexed(index, mColorMask);
}

void BlendStateExt::getColorMaskIndexed(const size_t index,
                                        bool *red,
                                        bool *green,
                                        bool *blue,
                                        bool *alpha) const
{
    ASSERT(index < mMaxDrawBuffers);
    UnpackColorMask(ColorMaskStorage::GetValueIndexed(index, mColorMask), red, green, blue, alpha);
}

DrawBufferMask BlendStateExt::compareColorMask(ColorMaskStorage::Type other) const
{
    return ColorMaskStorage::GetDiffMask(mColorMask, other);
}

BlendStateExt::EquationStorage::Type BlendStateExt::expandEquationValue(const GLenum mode) const
{
    return EquationStorage::GetReplicatedValue(FromGLenum<BlendEquationType>(mode),
                                               mMaxEquationMask);
}

BlendStateExt::EquationStorage::Type BlendStateExt::expandEquationColorIndexed(
    const size_t index) const
{
    return EquationStorage::GetReplicatedValue(
        EquationStorage::GetValueIndexed(index, mEquationColor), mMaxEquationMask);
}

BlendStateExt::EquationStorage::Type BlendStateExt::expandEquationAlphaIndexed(
    const size_t index) const
{
    return EquationStorage::GetReplicatedValue(
        EquationStorage::GetValueIndexed(index, mEquationAlpha), mMaxEquationMask);
}

void BlendStateExt::setEquations(const GLenum modeColor, const GLenum modeAlpha)
{
    mEquationColor = expandEquationValue(modeColor);
    mEquationAlpha = expandEquationValue(modeAlpha);
}

void BlendStateExt::setEquationsIndexed(const size_t index,
                                        const GLenum modeColor,
                                        const GLenum modeAlpha)
{
    ASSERT(index < mMaxDrawBuffers);
    EquationStorage::SetValueIndexed(index, FromGLenum<BlendEquationType>(modeColor),
                                     &mEquationColor);
    EquationStorage::SetValueIndexed(index, FromGLenum<BlendEquationType>(modeAlpha),
                                     &mEquationAlpha);
}

void BlendStateExt::setEquationsIndexed(const size_t index,
                                        const size_t sourceIndex,
                                        const BlendStateExt &source)
{
    ASSERT(index < mMaxDrawBuffers);
    ASSERT(sourceIndex < source.mMaxDrawBuffers);
    EquationStorage::SetValueIndexed(
        index, EquationStorage::GetValueIndexed(sourceIndex, source.mEquationColor),
        &mEquationColor);
    EquationStorage::SetValueIndexed(
        index, EquationStorage::GetValueIndexed(sourceIndex, source.mEquationAlpha),
        &mEquationAlpha);
}

GLenum BlendStateExt::getEquationColorIndexed(size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return ToGLenum(EquationStorage::GetValueIndexed(index, mEquationColor));
}

GLenum BlendStateExt::getEquationAlphaIndexed(size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return ToGLenum(EquationStorage::GetValueIndexed(index, mEquationAlpha));
}

DrawBufferMask BlendStateExt::compareEquations(const EquationStorage::Type color,
                                               const EquationStorage::Type alpha) const
{
    return EquationStorage::GetDiffMask(mEquationColor, color) |
           EquationStorage::GetDiffMask(mEquationAlpha, alpha);
}

BlendStateExt::FactorStorage::Type BlendStateExt::expandFactorValue(const GLenum func) const
{
    return FactorStorage::GetReplicatedValue(FromGLenum<BlendFactorType>(func), mMaxFactorMask);
}

BlendStateExt::FactorStorage::Type BlendStateExt::expandSrcColorIndexed(const size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return FactorStorage::GetReplicatedValue(FactorStorage::GetValueIndexed(index, mSrcColor),
                                             mMaxFactorMask);
}

BlendStateExt::FactorStorage::Type BlendStateExt::expandDstColorIndexed(const size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return FactorStorage::GetReplicatedValue(FactorStorage::GetValueIndexed(index, mDstColor),
                                             mMaxFactorMask);
}

BlendStateExt::FactorStorage::Type BlendStateExt::expandSrcAlphaIndexed(const size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return FactorStorage::GetReplicatedValue(FactorStorage::GetValueIndexed(index, mSrcAlpha),
                                             mMaxFactorMask);
}

BlendStateExt::FactorStorage::Type BlendStateExt::expandDstAlphaIndexed(const size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return FactorStorage::GetReplicatedValue(FactorStorage::GetValueIndexed(index, mDstAlpha),
                                             mMaxFactorMask);
}

void BlendStateExt::setFactors(const GLenum srcColor,
                               const GLenum dstColor,
                               const GLenum srcAlpha,
                               const GLenum dstAlpha)
{
    mSrcColor = expandFactorValue(srcColor);
    mDstColor = expandFactorValue(dstColor);
    mSrcAlpha = expandFactorValue(srcAlpha);
    mDstAlpha = expandFactorValue(dstAlpha);
}

void BlendStateExt::setFactorsIndexed(const size_t index,
                                      const GLenum srcColor,
                                      const GLenum dstColor,
                                      const GLenum srcAlpha,
                                      const GLenum dstAlpha)
{
    ASSERT(index < mMaxDrawBuffers);
    FactorStorage::SetValueIndexed(index, FromGLenum<BlendFactorType>(srcColor), &mSrcColor);
    FactorStorage::SetValueIndexed(index, FromGLenum<BlendFactorType>(dstColor), &mDstColor);
    FactorStorage::SetValueIndexed(index, FromGLenum<BlendFactorType>(srcAlpha), &mSrcAlpha);
    FactorStorage::SetValueIndexed(index, FromGLenum<BlendFactorType>(dstAlpha), &mDstAlpha);
}

void BlendStateExt::setFactorsIndexed(const size_t index,
                                      const size_t sourceIndex,
                                      const BlendStateExt &source)
{
    ASSERT(index < mMaxDrawBuffers);
    ASSERT(sourceIndex < source.mMaxDrawBuffers);
    FactorStorage::SetValueIndexed(
        index, FactorStorage::GetValueIndexed(sourceIndex, source.mSrcColor), &mSrcColor);
    FactorStorage::SetValueIndexed(
        index, FactorStorage::GetValueIndexed(sourceIndex, source.mDstColor), &mDstColor);
    FactorStorage::SetValueIndexed(
        index, FactorStorage::GetValueIndexed(sourceIndex, source.mSrcAlpha), &mSrcAlpha);
    FactorStorage::SetValueIndexed(
        index, FactorStorage::GetValueIndexed(sourceIndex, source.mDstAlpha), &mDstAlpha);
}

GLenum BlendStateExt::getSrcColorIndexed(size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return ToGLenum(FactorStorage::GetValueIndexed(index, mSrcColor));
}

GLenum BlendStateExt::getDstColorIndexed(size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return ToGLenum(FactorStorage::GetValueIndexed(index, mDstColor));
}

GLenum BlendStateExt::getSrcAlphaIndexed(size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return ToGLenum(FactorStorage::GetValueIndexed(index, mSrcAlpha));
}

GLenum BlendStateExt::getDstAlphaIndexed(size_t index) const
{
    ASSERT(index < mMaxDrawBuffers);
    return ToGLenum(FactorStorage::GetValueIndexed(index, mDstAlpha));
}

DrawBufferMask BlendStateExt::compareFactors(const FactorStorage::Type srcColor,
                                             const FactorStorage::Type dstColor,
                                             const FactorStorage::Type srcAlpha,
                                             const FactorStorage::Type dstAlpha) const
{
    return FactorStorage::GetDiffMask(mSrcColor, srcColor) |
           FactorStorage::GetDiffMask(mDstColor, dstColor) |
           FactorStorage::GetDiffMask(mSrcAlpha, srcAlpha) |
           FactorStorage::GetDiffMask(mDstAlpha, dstAlpha);
}

static void MinMax(int a, int b, int *minimum, int *maximum)
{
    if (a < b)
    {
        *minimum = a;
        *maximum = b;
    }
    else
    {
        *minimum = b;
        *maximum = a;
    }
}

Rectangle Rectangle::flip(bool flipX, bool flipY) const
{
    Rectangle flipped = *this;
    if (flipX)
    {
        flipped.x     = flipped.x + flipped.width;
        flipped.width = -flipped.width;
    }
    if (flipY)
    {
        flipped.y      = flipped.y + flipped.height;
        flipped.height = -flipped.height;
    }
    return flipped;
}

Rectangle Rectangle::removeReversal() const
{
    return flip(isReversedX(), isReversedY());
}

bool Rectangle::encloses(const gl::Rectangle &inside) const
{
    return x0() <= inside.x0() && y0() <= inside.y0() && x1() >= inside.x1() && y1() >= inside.y1();
}

bool ClipRectangle(const Rectangle &source, const Rectangle &clip, Rectangle *intersection)
{
    int minSourceX, maxSourceX, minSourceY, maxSourceY;
    MinMax(source.x, source.x + source.width, &minSourceX, &maxSourceX);
    MinMax(source.y, source.y + source.height, &minSourceY, &maxSourceY);

    int minClipX, maxClipX, minClipY, maxClipY;
    MinMax(clip.x, clip.x + clip.width, &minClipX, &maxClipX);
    MinMax(clip.y, clip.y + clip.height, &minClipY, &maxClipY);

    if (minSourceX >= maxClipX || maxSourceX <= minClipX || minSourceY >= maxClipY ||
        maxSourceY <= minClipY)
    {
        return false;
    }
    if (intersection)
    {
        intersection->x      = std::max(minSourceX, minClipX);
        intersection->y      = std::max(minSourceY, minClipY);
        intersection->width  = std::min(maxSourceX, maxClipX) - std::max(minSourceX, minClipX);
        intersection->height = std::min(maxSourceY, maxClipY) - std::max(minSourceY, minClipY);
    }
    return true;
}

bool Box::operator==(const Box &other) const
{
    return (x == other.x && y == other.y && z == other.z && width == other.width &&
            height == other.height && depth == other.depth);
}

bool Box::operator!=(const Box &other) const
{
    return !(*this == other);
}

Rectangle Box::toRect() const
{
    ASSERT(z == 0 && depth == 1);
    return Rectangle(x, y, width, height);
}

bool Box::coversSameExtent(const Extents &size) const
{
    return x == 0 && y == 0 && z == 0 && width == size.width && height == size.height &&
           depth == size.depth;
}

bool operator==(const Offset &a, const Offset &b)
{
    return a.x == b.x && a.y == b.y && a.z == b.z;
}

bool operator!=(const Offset &a, const Offset &b)
{
    return !(a == b);
}

bool operator==(const Extents &lhs, const Extents &rhs)
{
    return lhs.width == rhs.width && lhs.height == rhs.height && lhs.depth == rhs.depth;
}

bool operator!=(const Extents &lhs, const Extents &rhs)
{
    return !(lhs == rhs);
}

bool ValidateComponentTypeMasks(unsigned long outputTypes,
                                unsigned long inputTypes,
                                unsigned long outputMask,
                                unsigned long inputMask)
{
    static_assert(IMPLEMENTATION_MAX_DRAW_BUFFERS <= kMaxComponentTypeMaskIndex,
                  "Output/input masks should fit into 16 bits - 1 bit per draw buffer. The "
                  "corresponding type masks should fit into 32 bits - 2 bits per draw buffer.");
    static_assert(MAX_VERTEX_ATTRIBS <= kMaxComponentTypeMaskIndex,
                  "Output/input masks should fit into 16 bits - 1 bit per attrib. The "
                  "corresponding type masks should fit into 32 bits - 2 bits per attrib.");

    // For performance reasons, draw buffer and attribute type validation is done using bit masks.
    // We store two bits representing the type split, with the low bit in the lower 16 bits of the
    // variable, and the high bit in the upper 16 bits of the variable. This is done so we can AND
    // with the elswewhere used DrawBufferMask or AttributeMask.

    // OR the masks with themselves, shifted 16 bits. This is to match our split type bits.
    outputMask |= (outputMask << kMaxComponentTypeMaskIndex);
    inputMask |= (inputMask << kMaxComponentTypeMaskIndex);

    // To validate:
    // 1. Remove any indexes that are not enabled in the input (& inputMask)
    // 2. Remove any indexes that exist in output, but not in input (& outputMask)
    // 3. Use == to verify equality
    return (outputTypes & inputMask) == ((inputTypes & outputMask) & inputMask);
}

GLsizeiptr GetBoundBufferAvailableSize(const OffsetBindingPointer<Buffer> &binding)
{
    Buffer *buffer = binding.get();
    if (buffer)
    {
        if (binding.getSize() == 0)
            return static_cast<GLsizeiptr>(buffer->getSize());
        angle::CheckedNumeric<GLintptr> offset       = binding.getOffset();
        angle::CheckedNumeric<GLsizeiptr> size       = binding.getSize();
        angle::CheckedNumeric<GLsizeiptr> bufferSize = buffer->getSize();
        auto end                                     = offset + size;
        auto clampedSize                             = size;
        auto difference                              = end - bufferSize;
        if (!difference.IsValid())
        {
            return 0;
        }
        if (difference.ValueOrDie() > 0)
        {
            clampedSize = size - difference;
        }
        return clampedSize.ValueOrDefault(0);
    }
    else
    {
        return 0;
    }
}

}  // namespace gl
kc3-lang/angle/src/libANGLE/angletypes.cpp

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kc3-lang/angle /src/libANGLE/angletypes.cpp
