Method createConversion

glslang/MachineIndependent/Intermediate.cpp:600–680

This is 'mechanism' here, it does any conversion told. It is about basic type, not about shape. The policy comes from the shader or the calling code.

// It is about basic type, not about shape.
// The policy comes from the shader or the calling code.
TIntermTyped* TIntermediate::createConversion(TBasicType convertTo, TIntermTyped* node) const
{
    //
    // Add a new newNode for the conversion.
    //

    bool convertToIntTypes = (convertTo == EbtInt8  || convertTo == EbtUint8  ||
                              convertTo == EbtInt16 || convertTo == EbtUint16 ||
                              convertTo == EbtInt   || convertTo == EbtUint   ||
                              convertTo == EbtInt64 || convertTo == EbtUint64);

    bool convertFromIntTypes = (node->getBasicType() == EbtInt8  || node->getBasicType() == EbtUint8  ||
                                node->getBasicType() == EbtInt16 || node->getBasicType() == EbtUint16 ||
                                node->getBasicType() == EbtInt   || node->getBasicType() == EbtUint   ||
                                node->getBasicType() == EbtInt64 || node->getBasicType() == EbtUint64);

    bool convertToFloatTypes = (convertTo == EbtFloat16 || convertTo == EbtBFloat16 || convertTo == EbtFloat || convertTo == EbtDouble ||
                                convertTo == EbtFloatE5M2 || convertTo == EbtFloatE4M3);

    bool convertFromFloatTypes = (node->getBasicType() == EbtFloat16 ||
                                  node->getBasicType() == EbtBFloat16 ||
                                  node->getBasicType() == EbtFloat ||
                                  node->getBasicType() == EbtDouble ||
                                  node->getBasicType() == EbtFloatE5M2 ||
                                  node->getBasicType() == EbtFloatE4M3);

    if (((convertTo == EbtInt8 || convertTo == EbtUint8) && ! convertFromIntTypes) ||
        ((node->getBasicType() == EbtInt8 || node->getBasicType() == EbtUint8) && ! convertToIntTypes)) {
        if (! getArithemeticInt8Enabled()) {
            return nullptr;
        }
    }

    if (((convertTo == EbtInt16 || convertTo == EbtUint16) && ! convertFromIntTypes) ||
        ((node->getBasicType() == EbtInt16 || node->getBasicType() == EbtUint16) && ! convertToIntTypes)) {
        if (! getArithemeticInt16Enabled()) {
            return nullptr;
        }
    }

    if ((convertTo == EbtFloat16 && ! convertFromFloatTypes) ||
        (node->getBasicType() == EbtFloat16 && ! convertToFloatTypes)) {
        if (! getArithemeticFloat16Enabled()) {
            return nullptr;
        }
    }

    TIntermUnary* newNode = nullptr;
    TOperator newOp = EOpNull;
    if (!buildConvertOp(convertTo, node->getBasicType(), newOp)) {
        return nullptr;
    }

    TType newType(convertTo, EvqTemporary, node->getVectorSize(), node->getMatrixCols(), node->getMatrixRows());
    if (node->getType().isLongVector()) {
        newType.shallowCopy(node->getType());
        newType.setBasicType(convertTo);
        newType.makeTemporary();