short Assign::codeGen(Generator * generator)
{
Attributes ** attr;
// If this Assign has already been codeGenned, then bug out early.
//
MapInfo * assignMapInfo = generator->getMapInfoAsIs(getValueId());
if (assignMapInfo && assignMapInfo->isCodeGenerated())
return 0;
// If the left child (lvalue) is already in the map table, then
// add the Assign value Id to the map table with the same attributes
// as the let child. Mark the Assign node as codeGenned. Also, allocate
// space for the attributes.
//
MapInfo *leftChildMapInfo = generator->getMapInfoAsIs
(child(0)->castToItemExpr()->getValueId());
if (leftChildMapInfo)
{
if (! assignMapInfo)
assignMapInfo =
generator->addMapInfoToThis(generator->getLastMapTable(),
getValueId(),
leftChildMapInfo->getAttr());
assignMapInfo->codeGenerated();
attr = new(generator->wHeap()) Attributes*[2];
// Set the result attribute
//
attr[0] = assignMapInfo->getAttr();
}
// Otherwise, go ahead and generate the Assign attributes (which also
// allocates space for the Assign result). Add the left child to the
// map table with the same attributes as the Assign node.
//
else
{
generator->getExpGenerator()->genItemExpr(this, &attr, 2, 0);
generator->addMapInfoToThis(generator->getLastMapTable(),
child(0)->castToItemExpr()->getValueId(),
attr[0]);
}
attr[0]->resetShowplan();
// Now, generate code for the right child (rvalue).
//
generator->getExpGenerator()->setClauseLinked(FALSE);
child(1)->codeGen(generator);
attr[1] = generator->getAttr(child(1));
generator->getExpGenerator()->setClauseLinked(FALSE);
ex_conv_clause * conv_clause =
new(generator->getSpace()) ex_conv_clause
(getOperatorType(), attr, generator->getSpace());
generator->getExpGenerator()->linkClause(this, conv_clause);
return 0;
}
// A transformation method for protecting sequence functions from not
// being evaluated due to short-circuit evaluation. This is the base
// class implementation which simply recurses on the children unless
// they have already been code-generated.
//
void ItemExpr::protectiveSequenceFunctionTransformation(Generator *generator)
{
for(Int32 i=0; i<getArity(); i++)
{
MapInfo *mapInfo = generator->getMapInfoAsIs(child(i));
if(!mapInfo || !mapInfo->isCodeGenerated())
child(i)->protectiveSequenceFunctionTransformation(generator);
}
}
short Aggregate::codeGen(Generator * generator)
{
Attributes ** attr;
// If this Aggr has already been codeGenned, then bug out early.
//
MapInfo * aggrMapInfo = generator->getMapInfoAsIs(getValueId());
if (aggrMapInfo && aggrMapInfo->isCodeGenerated())
return 0;
if (getOperatorType() != ITM_ONE_ROW)
{
if (generator->getExpGenerator()->genItemExpr(this, &attr, (1+getArity()), -1) == 1)
return 0;
}
ex_clause * clause = 0;
switch (getOperatorType())
{
case ITM_ONE_ROW:
{
Int32 degree = 0;
findnumleaves(this, degree); // degree has number of leaves in the tree
if (generator->getExpGenerator()->genItemExpr(this, &attr, (1+degree),
-1) == 1)
return 0;
clause =
new(generator->getSpace()) ex_aggr_one_row_clause(getOperatorType(),
(short)(1+degree),
attr,
generator->getSpace());
}
break;
case ITM_ANY_TRUE_MAX:
{
clause =
new(generator->getSpace()) ex_aggr_any_true_max_clause(getOperatorType(),
(short)(1+getArity()),
attr, generator->getSpace());
}
break;
default:
break;
}
GenAssert(clause, "Aggregate::codeGen -- missing clause!");
generator->getExpGenerator()->linkClause(this, clause);
return 0;
}
void
markGeneratedEntries(Generator *generator, ItemExpr *item, ValueIdSet &marks)
{
if(item) {
MapInfo *mapInfo =
generator->getMapInfoAsIs(item->getValueId());
if(mapInfo && mapInfo->isCodeGenerated())
marks += item->getValueId();
for(Int32 i = 0; i < item->getArity(); i++) {
markGeneratedEntries(generator,item->child(i), marks);
}
}
}
// ItmPersistentExpressionVar::codeGen
//
// Adds the persistent variable to the expression generator.
//
short ItmPersistentExpressionVar::codeGen(Generator * generator) {
// If the variable has already been codeGenned, bug out...
//
MapInfo * mi = generator->getMapInfoAsIs(getValueId());
if (mi && mi->isCodeGenerated()) return 0;
// Otherwise, generate the code and add it to the map table.
//
generator->getExpGenerator()->addPersistent(getValueId(),
generator->getMapTable());
// Add the initial value to the persistent list in the ExpGenerator.
//
generator->getExpGenerator()->linkPersistent(this);
// ok...
//
return 0;
}