Method createCompositeCompare

SPIRV/SpvBuilder.cpp:4057–4123

External comments in header. Operates recursively to visit the composite's hierarchy.

// External comments in header.
// Operates recursively to visit the composite's hierarchy.
Id Builder::createCompositeCompare(Decoration precision, Id value1, Id value2, bool equal)
{
    Id boolType = makeBoolType();
    Id valueType = getTypeId(value1);

    Id resultId = NoResult;

    int numConstituents = getNumTypeConstituents(valueType);

    // Scalars and Vectors

    if (isScalarType(valueType) || isVectorType(valueType)) {
        assert(valueType == getTypeId(value2));
        // These just need a single comparison, just have
        // to figure out what it is.
        Op op;
        switch (getMostBasicTypeClass(valueType)) {
        case Op::OpTypeFloat:
            op = equal ? Op::OpFOrdEqual : Op::OpFUnordNotEqual;
            break;
        case Op::OpTypeInt:
        default:
            op = equal ? Op::OpIEqual : Op::OpINotEqual;
            break;
        case Op::OpTypeBool:
            op = equal ? Op::OpLogicalEqual : Op::OpLogicalNotEqual;
            precision = NoPrecision;
            break;
        }

        if (isScalarType(valueType)) {
            // scalar
            resultId = createBinOp(op, boolType, value1, value2);
        } else {
            // vector
            resultId = createBinOp(op, makeVectorType(boolType, numConstituents), value1, value2);
            setPrecision(resultId, precision);
            // reduce vector compares...
            resultId = createUnaryOp(equal ? Op::OpAll : Op::OpAny, boolType, resultId);
        }

        return setPrecision(resultId, precision);
    }

    // Only structs, arrays, and matrices should be left.
    // They share in common the reduction operation across their constituents.
    assert(isAggregateType(valueType) || isMatrixType(valueType));

    // Compare each pair of constituents
    for (int constituent = 0; constituent < numConstituents; ++constituent) {
        std::vector<unsigned> indexes(1, constituent);
        Id constituentType1 = getContainedTypeId(getTypeId(value1), constituent);
        Id constituentType2 = getContainedTypeId(getTypeId(value2), constituent);
        Id constituent1 = createCompositeExtract(value1, constituentType1, indexes);
        Id constituent2 = createCompositeExtract(value2, constituentType2, indexes);

        Id subResultId = createCompositeCompare(precision, constituent1, constituent2, equal);