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diff --git a/src/3rdparty/angle/src/libANGLE/VaryingPacking.cpp b/src/3rdparty/angle/src/libANGLE/VaryingPacking.cpp
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+++ b/src/3rdparty/angle/src/libANGLE/VaryingPacking.cpp
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+//
+// Copyright 2015 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.
+//
+// VaryingPacking:
+//   Class which describes a mapping from varyings to registers, according
+//   to the spec, or using custom packing algorithms. We also keep a register
+//   allocation list for the D3D renderer.
+//
+
+#include "libANGLE/VaryingPacking.h"
+
+#include "common/utilities.h"
+#include "libANGLE/Program.h"
+#include "libANGLE/Shader.h"
+
+namespace gl
+{
+
+namespace
+{
+
+// true if varying x has a higher priority in packing than y
+bool ComparePackedVarying(const PackedVarying &x, const PackedVarying &y)
+{
+    // If the PackedVarying 'x' or 'y' to be compared is an array element, this clones an equivalent
+    // non-array shader variable 'vx' or 'vy' for actual comparison instead.
+    sh::ShaderVariable vx, vy;
+    const sh::ShaderVariable *px, *py;
+    if (x.isArrayElement())
+    {
+        vx           = *x.varying;
+        vx.arraySizes.clear();
+        px           = &vx;
+    }
+    else
+    {
+        px = x.varying;
+    }
+
+    if (y.isArrayElement())
+    {
+        vy           = *y.varying;
+        vy.arraySizes.clear();
+        py           = &vy;
+    }
+    else
+    {
+        py = y.varying;
+    }
+
+    return gl::CompareShaderVar(*px, *py);
+}
+
+}  // anonymous namespace
+
+// Implementation of VaryingPacking
+VaryingPacking::VaryingPacking(GLuint maxVaryingVectors, PackMode packMode)
+    : mRegisterMap(maxVaryingVectors), mPackMode(packMode)
+{
+}
+
+VaryingPacking::~VaryingPacking() = default;
+
+// Packs varyings into generic varying registers, using the algorithm from
+// See [OpenGL ES Shading Language 1.00 rev. 17] appendix A section 7 page 111
+// Also [OpenGL ES Shading Language 3.00 rev. 4] Section 11 page 119
+// Returns false if unsuccessful.
+bool VaryingPacking::packVarying(const PackedVarying &packedVarying)
+{
+    const auto &varying = *packedVarying.varying;
+
+    // "Non - square matrices of type matCxR consume the same space as a square matrix of type matN
+    // where N is the greater of C and R."
+    // Here we are a bit more conservative and allow packing non-square matrices more tightly.
+    // Make sure we use transposed matrix types to count registers correctly.
+    ASSERT(!varying.isStruct());
+    GLenum transposedType       = gl::TransposeMatrixType(varying.type);
+    unsigned int varyingRows    = gl::VariableRowCount(transposedType);
+    unsigned int varyingColumns = gl::VariableColumnCount(transposedType);
+
+    // "Variables of type mat2 occupies 2 complete rows."
+    // For non-WebGL contexts, we allow mat2 to occupy only two columns per row.
+    if (mPackMode == PackMode::WEBGL_STRICT && varying.type == GL_FLOAT_MAT2)
+    {
+        varyingColumns = 4;
+    }
+
+    // "Arrays of size N are assumed to take N times the size of the base type"
+    // GLSL ES 3.10 section 4.3.6: Output variables cannot be arrays of arrays or arrays of
+    // structures, so we may use getBasicTypeElementCount().
+    const unsigned int elementCount = varying.getBasicTypeElementCount();
+    varyingRows *= (packedVarying.isArrayElement() ? 1 : elementCount);
+
+    unsigned int maxVaryingVectors = static_cast<unsigned int>(mRegisterMap.size());
+
+    // Fail if we are packing a single over-large varying.
+    if (varyingRows > maxVaryingVectors)
+    {
+        return false;
+    }
+
+    // "For 2, 3 and 4 component variables packing is started using the 1st column of the 1st row.
+    // Variables are then allocated to successive rows, aligning them to the 1st column."
+    if (varyingColumns >= 2 && varyingColumns <= 4)
+    {
+        for (unsigned int row = 0; row <= maxVaryingVectors - varyingRows; ++row)
+        {
+            if (isFree(row, 0, varyingRows, varyingColumns))
+            {
+                insert(row, 0, packedVarying);
+                return true;
+            }
+        }
+
+        // "For 2 component variables, when there are no spare rows, the strategy is switched to
+        // using the highest numbered row and the lowest numbered column where the variable will
+        // fit."
+        if (varyingColumns == 2)
+        {
+            for (unsigned int r = maxVaryingVectors - varyingRows + 1; r-- >= 1;)
+            {
+                if (isFree(r, 2, varyingRows, 2))
+                {
+                    insert(r, 2, packedVarying);
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+
+    // "1 component variables have their own packing rule. They are packed in order of size, largest
+    // first. Each variable is placed in the column that leaves the least amount of space in the
+    // column and aligned to the lowest available rows within that column."
+    ASSERT(varyingColumns == 1);
+    unsigned int contiguousSpace[4]     = {0};
+    unsigned int bestContiguousSpace[4] = {0};
+    unsigned int totalSpace[4]          = {0};
+
+    for (unsigned int row = 0; row < maxVaryingVectors; ++row)
+    {
+        for (unsigned int column = 0; column < 4; ++column)
+        {
+            if (mRegisterMap[row][column])
+            {
+                contiguousSpace[column] = 0;
+            }
+            else
+            {
+                contiguousSpace[column]++;
+                totalSpace[column]++;
+
+                if (contiguousSpace[column] > bestContiguousSpace[column])
+                {
+                    bestContiguousSpace[column] = contiguousSpace[column];
+                }
+            }
+        }
+    }
+
+    unsigned int bestColumn = 0;
+    for (unsigned int column = 1; column < 4; ++column)
+    {
+        if (bestContiguousSpace[column] >= varyingRows &&
+            (bestContiguousSpace[bestColumn] < varyingRows ||
+             totalSpace[column] < totalSpace[bestColumn]))
+        {
+            bestColumn = column;
+        }
+    }
+
+    if (bestContiguousSpace[bestColumn] >= varyingRows)
+    {
+        for (unsigned int row = 0; row < maxVaryingVectors; row++)
+        {
+            if (isFree(row, bestColumn, varyingRows, 1))
+            {
+                for (unsigned int arrayIndex = 0; arrayIndex < varyingRows; ++arrayIndex)
+                {
+                    // If varyingRows > 1, it must be an array.
+                    PackedVaryingRegister registerInfo;
+                    registerInfo.packedVarying     = &packedVarying;
+                    registerInfo.registerRow       = row + arrayIndex;
+                    registerInfo.registerColumn    = bestColumn;
+                    registerInfo.varyingArrayIndex =
+                        (packedVarying.isArrayElement() ? packedVarying.arrayIndex : arrayIndex);
+                    registerInfo.varyingRowIndex   = 0;
+                    // Do not record register info for builtins.
+                    // TODO(jmadill): Clean this up.
+                    if (!packedVarying.varying->isBuiltIn())
+                    {
+                        mRegisterList.push_back(registerInfo);
+                    }
+                    mRegisterMap[row + arrayIndex][bestColumn] = true;
+                }
+                break;
+            }
+        }
+        return true;
+    }
+
+    return false;
+}
+
+bool VaryingPacking::isFree(unsigned int registerRow,
+                            unsigned int registerColumn,
+                            unsigned int varyingRows,
+                            unsigned int varyingColumns) const
+{
+    for (unsigned int row = 0; row < varyingRows; ++row)
+    {
+        ASSERT(registerRow + row < mRegisterMap.size());
+        for (unsigned int column = 0; column < varyingColumns; ++column)
+        {
+            ASSERT(registerColumn + column < 4);
+            if (mRegisterMap[registerRow + row][registerColumn + column])
+            {
+                return false;
+            }
+        }
+    }
+
+    return true;
+}
+
+void VaryingPacking::insert(unsigned int registerRow,
+                            unsigned int registerColumn,
+                            const PackedVarying &packedVarying)
+{
+    unsigned int varyingRows    = 0;
+    unsigned int varyingColumns = 0;
+
+    const auto &varying = *packedVarying.varying;
+    ASSERT(!varying.isStruct());
+    GLenum transposedType = gl::TransposeMatrixType(varying.type);
+    varyingRows           = gl::VariableRowCount(transposedType);
+    varyingColumns        = gl::VariableColumnCount(transposedType);
+
+    PackedVaryingRegister registerInfo;
+    registerInfo.packedVarying  = &packedVarying;
+    registerInfo.registerColumn = registerColumn;
+
+    // GLSL ES 3.10 section 4.3.6: Output variables cannot be arrays of arrays or arrays of
+    // structures, so we may use getBasicTypeElementCount().
+    const unsigned int arrayElementCount = varying.getBasicTypeElementCount();
+    for (unsigned int arrayElement = 0; arrayElement < arrayElementCount; ++arrayElement)
+    {
+        if (packedVarying.isArrayElement() && arrayElement != packedVarying.arrayIndex)
+        {
+            continue;
+        }
+        for (unsigned int varyingRow = 0; varyingRow < varyingRows; ++varyingRow)
+        {
+            registerInfo.registerRow     = registerRow + (arrayElement * varyingRows) + varyingRow;
+            registerInfo.varyingRowIndex = varyingRow;
+            registerInfo.varyingArrayIndex = arrayElement;
+            // Do not record register info for builtins.
+            // TODO(jmadill): Clean this up.
+            if (!packedVarying.varying->isBuiltIn())
+            {
+                mRegisterList.push_back(registerInfo);
+            }
+
+            for (unsigned int columnIndex = 0; columnIndex < varyingColumns; ++columnIndex)
+            {
+                mRegisterMap[registerInfo.registerRow][registerColumn + columnIndex] = true;
+            }
+        }
+    }
+}
+
+bool VaryingPacking::collectAndPackUserVaryings(gl::InfoLog &infoLog,
+                                                const Program::MergedVaryings &mergedVaryings,
+                                                const std::vector<std::string> &tfVaryings)
+{
+    std::set<std::string> uniqueFullNames;
+    mPackedVaryings.clear();
+
+    for (const auto &ref : mergedVaryings)
+    {
+        const sh::Varying *input  = ref.second.vertex;
+        const sh::Varying *output = ref.second.fragment;
+
+        // Only pack statically used varyings that have a matched input or output, plus special
+        // builtins.
+        if (((input && output) || (output && output->isBuiltIn())) && output->staticUse)
+        {
+            // Will get the vertex shader interpolation by default.
+            auto interpolation = ref.second.get()->interpolation;
+
+            // Note that we lose the vertex shader static use information here. The data for the
+            // variable is taken from the fragment shader.
+            if (output->isStruct())
+            {
+                ASSERT(!output->isArray());
+                for (const auto &field : output->fields)
+                {
+                    ASSERT(!field.isStruct() && !field.isArray());
+                    mPackedVaryings.push_back(PackedVarying(field, interpolation, output->name));
+                    uniqueFullNames.insert(mPackedVaryings.back().nameWithArrayIndex());
+                }
+            }
+            else
+            {
+                mPackedVaryings.push_back(PackedVarying(*output, interpolation));
+                uniqueFullNames.insert(mPackedVaryings.back().nameWithArrayIndex());
+            }
+            continue;
+        }
+
+        // Keep Transform FB varyings in the merged list always.
+        if (!input)
+        {
+            continue;
+        }
+
+        for (const std::string &tfVarying : tfVaryings)
+        {
+            std::vector<unsigned int> subscripts;
+            std::string baseName = ParseResourceName(tfVarying, &subscripts);
+            size_t subscript     = GL_INVALID_INDEX;
+            if (!subscripts.empty())
+            {
+                subscript = subscripts.back();
+            }
+            // Already packed for fragment shader.
+            if (uniqueFullNames.count(tfVarying) > 0 || uniqueFullNames.count(baseName) > 0)
+            {
+                continue;
+            }
+            // Array as a whole and array element conflict has already been checked in
+            // linkValidateTransformFeedback.
+            if (baseName == input->name)
+            {
+                // Transform feedback for varying structs is underspecified.
+                // See Khronos bug 9856.
+                // TODO(jmadill): Figure out how to be spec-compliant here.
+                if (!input->isStruct() && tfVarying.compare(0, 3, "gl_") != 0)
+                {
+                    mPackedVaryings.push_back(PackedVarying(*input, input->interpolation));
+                    mPackedVaryings.back().vertexOnly = true;
+                    mPackedVaryings.back().arrayIndex = static_cast<GLuint>(subscript);
+                    uniqueFullNames.insert(tfVarying);
+                }
+                // Continue to match next array element for 'input' if the current match is array
+                // element.
+                if (subscript == GL_INVALID_INDEX)
+                {
+                    break;
+                }
+            }
+        }
+    }
+
+    std::sort(mPackedVaryings.begin(), mPackedVaryings.end(), ComparePackedVarying);
+
+    return packUserVaryings(infoLog, mPackedVaryings, tfVaryings);
+}
+
+// See comment on packVarying.
+bool VaryingPacking::packUserVaryings(gl::InfoLog &infoLog,
+                                      const std::vector<PackedVarying> &packedVaryings,
+                                      const std::vector<std::string> &transformFeedbackVaryings)
+{
+
+    // "Variables are packed into the registers one at a time so that they each occupy a contiguous
+    // subrectangle. No splitting of variables is permitted."
+    for (const PackedVarying &packedVarying : packedVaryings)
+    {
+        if (!packVarying(packedVarying))
+        {
+            infoLog << "Could not pack varying " << packedVarying.nameWithArrayIndex();
+            return false;
+        }
+    }
+
+    // Sort the packed register list
+    std::sort(mRegisterList.begin(), mRegisterList.end());
+
+    // Assign semantic indices
+    for (unsigned int semanticIndex = 0;
+         semanticIndex < static_cast<unsigned int>(mRegisterList.size()); ++semanticIndex)
+    {
+        mRegisterList[semanticIndex].semanticIndex = semanticIndex;
+    }
+
+    return true;
+}
+
+unsigned int VaryingPacking::getRegisterCount() const
+{
+    unsigned int count = 0;
+
+    for (const Register &reg : mRegisterMap)
+    {
+        if (reg.data[0] || reg.data[1] || reg.data[2] || reg.data[3])
+        {
+            ++count;
+        }
+    }
+
+    return count;
+}
+
+}  // namespace rx