//! Takes an AST node subclass and returns an appropriate DataTarget object that contains
//! the same information. Supported AST node types are:
//! - SymbolASTNode
//! - NaturalLocationASTNode
//! - AddressRangeASTNode
//!
//! \exception elftosb::semantic_error Thrown if a semantic problem is found with
//! the target node.
DataTarget * ConversionController::createTargetFromNode(ASTNode * targetNode)
{
assert(targetNode);
DataTarget * target = NULL;
SymbolASTNode * symbolNode;
NaturalLocationASTNode * naturalNode;
AddressRangeASTNode * addressNode;
if (symbolNode = dynamic_cast<SymbolASTNode*>(targetNode))
{
SourceFile * sourceFile = getSourceFromName(symbolNode->getSource(), symbolNode->getFirstLine());
std::string * symbolName = symbolNode->getSymbolName();
// symbol name is optional
if (symbolName)
{
if (!sourceFile->supportsNamedSymbols())
{
throw std::runtime_error(format_string("line %d: source does not support symbols", symbolNode->getFirstLine()));
}
target = sourceFile->createDataTargetForSymbol(*symbolName);
if (!target)
{
throw std::runtime_error(format_string("line %d: source does not have a symbol with that name", symbolNode->getFirstLine()));
}
}
else
{
// no symbol name was specified so use entry point
target = sourceFile->createDataTargetForEntryPoint();
if (!target)
{
throw std::runtime_error(format_string("line %d: source does not have an entry point", symbolNode->getFirstLine()));
}
}
}
else if (naturalNode = dynamic_cast<NaturalLocationASTNode*>(targetNode))
{
// the target is the source's natural location
target = new NaturalDataTarget();
}
else if (addressNode = dynamic_cast<AddressRangeASTNode*>(targetNode))
{
// evaluate begin address
ExprASTNode * beginExpr = dynamic_cast<ExprASTNode*>(addressNode->getBegin());
if (!beginExpr)
{
throw semantic_error("address range must always have a beginning expression");
}
IntConstExprASTNode * beginIntExpr = dynamic_cast<IntConstExprASTNode*>(beginExpr->reduce(m_context));
if (!beginIntExpr)
{
throw semantic_error("address range begin did not evaluate to an integer");
}
uint32_t beginAddress = static_cast<uint32_t>(beginIntExpr->getValue());
// evaluate end address
ExprASTNode * endExpr = dynamic_cast<ExprASTNode*>(addressNode->getEnd());
uint32_t endAddress = 0;
bool hasEndAddress = false;
if (endExpr)
{
IntConstExprASTNode * endIntExpr = dynamic_cast<IntConstExprASTNode*>(endExpr->reduce(m_context));
if (!endIntExpr)
{
throw semantic_error("address range end did not evaluate to an integer");
}
endAddress = static_cast<uint32_t>(endIntExpr->getValue());
hasEndAddress = true;
}
// create target
if (hasEndAddress)
{
target = new ConstantDataTarget(beginAddress, endAddress);
}
else
{
target = new ConstantDataTarget(beginAddress);
}
}
else
{
throw semantic_error("unexpected load target node type");
}
return target;
}
