Method LookupFunction

shadercompiler/SymbolTable.cpp:206–333

}

Symbol* ScopeSymbolTable::LookupFunction( const InlineString& name, ASTNode* callNode, std::string& diagnosticMessage ) const
{
	diagnosticMessage = "";

	std::vector<std::pair<Symbol*, int>> overrides;
	const ScopeSymbolTable* scope = this;
	while( scope )
	{
		for( auto it = scope->m_symbols.begin(); it != scope->m_symbols.end(); ++it )
		{
			if( ( *it )->name == name )
			{
				overrides.push_back( std::make_pair( *it, 100000 ) );
			}
		}
		scope = scope->m_parent;
	}
	if( overrides.empty() )
	{
		return nullptr;
	}
	if( overrides.size() == 1 )
	{
		return overrides[0].first;
	}

	// overrides[i] is NT_FUNCTION_HEADER or NT_FUNCTION_DEFINITION
	// callNode is NT_FUNCTION_CALL
	Symbol* bestOverride = nullptr;
	int bestScore = 0;
	for( auto it = overrides.begin(); it != overrides.end(); ++it )
	{
		ASTNode* node = it->first->definition;
		if( node == nullptr )
		{
			continue;
		}
		if( node->GetNodeType() == NT_FUNCTION_DEFINITION )
		{
			node = node->GetChildOrNull( 0 );
		}
		if( node == nullptr )
		{
			continue;
		}
		auto parameterCount = node->GetChildrenCount();
		auto argumentCount = callNode->GetChildrenCount();

		if( argumentCount > parameterCount )
		{
			continue;
		}
		if( argumentCount < parameterCount )
		{
			// Check if next parameter after callNode->GetChildrenCount()
			// has default value.
			ASTNode* nextParameter = node->GetChild( argumentCount );
			if( nextParameter == nullptr )