C++ TIntermSelection类代码示例

//
// For "if" test nodes.  There are three children; a condition,
// a true path, and a false path.  The two paths are in the
// nodePair.
//
// Returns the selection node created.
//
TIntermNode *TIntermediate::addSelection(
    TIntermTyped *cond, TIntermNodePair nodePair, const TSourceLoc &line)
{
    //
    // For compile time constant selections, prune the code and
    // test now.
    //

    if (cond->getAsTyped() && cond->getAsTyped()->getAsConstantUnion())
    {
        if (cond->getAsConstantUnion()->getBConst(0) == true)
        {
            return nodePair.node1 ? setAggregateOperator(
                nodePair.node1, EOpSequence, nodePair.node1->getLine()) : NULL;
        }
        else
        {
            return nodePair.node2 ? setAggregateOperator(
                nodePair.node2, EOpSequence, nodePair.node2->getLine()) : NULL;
        }
    }

    TIntermSelection *node = new TIntermSelection(
        cond, nodePair.node1, nodePair.node2);
    node->setLine(line);

    return node;
}

//
// For "?:" test nodes.  There are three children; a condition,
// a true path, and a false path.  The two paths are specified
// as separate parameters.
//
// Returns the selection node created, or 0 if one could not be.
//
TIntermTyped *TIntermediate::addSelection(
    TIntermTyped *cond, TIntermTyped *trueBlock, TIntermTyped *falseBlock,
    const TSourceLoc &line)
{
    if (!cond || !trueBlock || !falseBlock ||
        trueBlock->getType() != falseBlock->getType())
    {
        return NULL;
    }

    //
    // See if all the operands are constant, then fold it otherwise not.
    //

    if (cond->getAsConstantUnion() &&
        trueBlock->getAsConstantUnion() &&
        falseBlock->getAsConstantUnion())
    {
        if (cond->getAsConstantUnion()->getBConst(0))
            return trueBlock;
        else
            return falseBlock;
    }

    //
    // Make a selection node.
    //
    TIntermSelection *node = new TIntermSelection(
        cond, trueBlock, falseBlock, trueBlock->getType());
    node->getTypePointer()->setQualifier(EvqTemporary);
    node->setLine(line);

    return node;
}

//
// For "?:" test nodes.  There are three children; a condition,
// a true path, and a false path.  The two paths are specified
// as separate parameters.
//
// Returns the selection node created, or 0 if one could not be.
//
TIntermTyped* TIntermediate::addSelection(TIntermTyped* cond, TIntermTyped* trueBlock, TIntermTyped* falseBlock, TSourceLoc line)
{
    //
    // Get compatible types.
    //
    TIntermTyped* child = addConversion(EOpSequence, trueBlock->getType(), falseBlock);
    if (child)
        falseBlock = child;
    else {
        child = addConversion(EOpSequence, falseBlock->getType(), trueBlock);
        if (child)
            trueBlock = child;
        else
            return 0;
    }

    //
    // See if all the operands are constant, then fold it otherwise not.
    //

    if (cond->getAsConstantUnion() && trueBlock->getAsConstantUnion() && falseBlock->getAsConstantUnion()) {
        if (cond->getAsConstantUnion()->getUnionArrayPointer()->getBConst())
            return trueBlock;
        else
            return falseBlock;
    }

    //
    // Make a selection node.
    //
    TIntermSelection* node = new TIntermSelection(cond, trueBlock, falseBlock, trueBlock->getType());
    node->setLine(line);

    return node;
}

//
// For "?:" test nodes.  There are three children; a condition,
// a true path, and a false path.  The two paths are specified
// as separate parameters.
//
// Returns the selection node created, or one of trueBlock and falseBlock if the expression could be folded.
//
TIntermTyped *TIntermediate::addSelection(TIntermTyped *cond, TIntermTyped *trueBlock, TIntermTyped *falseBlock,
                                          const TSourceLoc &line)
{
    // Right now it's safe to fold ternary operators only when all operands
    // are constant. If only the condition is constant, it's theoretically
    // possible to fold the ternary operator, but that requires making sure
    // that the node returned from here won't be treated as a constant
    // expression in case the node that gets eliminated was not a constant
    // expression.
    if (cond->getAsConstantUnion() &&
        trueBlock->getAsConstantUnion() &&
        falseBlock->getAsConstantUnion())
    {
        if (cond->getAsConstantUnion()->getBConst(0))
            return trueBlock;
        else
            return falseBlock;
    }

    //
    // Make a selection node.
    //
    TIntermSelection *node = new TIntermSelection(cond, trueBlock, falseBlock, trueBlock->getType());
    node->getTypePointer()->setQualifier(EvqTemporary);
    node->setLine(line);

    return node;
}

// For "if" test nodes.  There are three children; a condition,
// a true path, and a false path.  The two paths are in the
// nodePair.
TIntermNode* ir_add_selection(TIntermTyped* cond, TIntermNodePair nodePair, TSourceLoc line, TInfoSink& infoSink)
{   
   // Convert float/int to bool
   if ( cond->getBasicType() != EbtBool)
   {
      cond = ir_add_conversion (EOpConstructBool,
                             TType (EbtBool, cond->getPrecision(), cond->getQualifier(), cond->getColsCount(), cond->getRowsCount(), cond->isMatrix(), cond->isArray()),
                             cond, infoSink);
   }

   TIntermSelection* node = new TIntermSelection(cond, nodePair.node1, nodePair.node2);
   node->setLine(line);

   return node;
}

//
// For "if" test nodes.  There are three children; a condition,
// a true path, and a false path.  The two paths are in the
// nodePair.
//
// Returns the selection node created.
//
TIntermNode* TIntermediate::addSelection(TIntermTyped* cond, TIntermNodePair nodePair, TSourceLoc line)
{
    //
    // For compile time constant selections, prune the code and 
    // test now.
    //
    
    if (cond->getAsTyped() && cond->getAsTyped()->getAsConstantUnion()) {
        if (cond->getAsTyped()->getAsConstantUnion()->getUnionArrayPointer()->getBConst())
            return nodePair.node1;
        else
            return nodePair.node2;
    }

    TIntermSelection* node = new TIntermSelection(cond, nodePair.node1, nodePair.node2);
    node->setLine(line);

    return node;
}

// For "if" test nodes.  There are three children; a condition,
// a true path, and a false path.  The two paths are in the
// nodePair.
TIntermNode* ir_add_selection(TIntermTyped* cond, TIntermNodePair nodePair, TSourceLoc line, TInfoSink& infoSink)
{   
   // Convert float/int to bool
   switch ( cond->getBasicType() )
   {
   case EbtFloat:
   case EbtInt:
      cond = ir_add_conversion (EOpConstructBool, 
                             TType (EbtBool, cond->getPrecision(), cond->getQualifier(), cond->getNominalSize(), cond->isMatrix(), cond->isArray()),
                             cond, infoSink);
      break;
   default:
      // Do nothing
      break;
   }

   TIntermSelection* node = new TIntermSelection(cond, nodePair.node1, nodePair.node2);
   node->setLine(line);

   return node;
}

bool ElseBlockRewriter::visitAggregate(Visit visit, TIntermAggregate *node)
{
    switch (node->getOp())
    {
      case EOpSequence:
        {
            for (size_t statementIndex = 0; statementIndex != node->getSequence().size(); statementIndex++)
            {
                TIntermNode *statement = node->getSequence()[statementIndex];
                TIntermSelection *selection = statement->getAsSelectionNode();
                if (selection && selection->getFalseBlock() != NULL)
                {
                    node->getSequence()[statementIndex] = rewriteSelection(selection);
                    delete selection;
                }
            }
        }
        break;

      default: break;
    }

    return true;
}