C++ Method::getCodeBuffer方法代码示例

/**
 * Parses the keyword "return" from the given token stack
 */
int CodeParser::parseKeyword_Return( Scope* scope, TokenStack* stack ) {
	// get the scope type
	ScopeType type = scope->getScopeType();
	if( type != METHOD_SCOPE ) {
		SYNTAX_ERROR( "Statement is only permissible within a method block", stack->last() );
		return -1;
	}

	// get the method instance
	Method* method = (Method*)scope;

	// TODO support "return value" syntax

	// add the instruction
	INSTRUCTION_T instruction = RET << A_OP;
	method->getCodeBuffer()->putInstruction( instruction );
	return 0;
}

/**
 * Parses a method definition
 */
int CodeParser::parseMethod( Scope* scope, const char* name, TypeReference* type, TokenStack* stack ) {
	int errorCode = 0;
	const char* signature;
	list<Parameter*> params;
	Method *method;

	// step through the tokens ...
	int step = 0;
	bool done = false;
	while( !errorCode && !done && stack->hasNext() ) {
		switch( ++step ) {
			// step 1: create the method
			case 1:
				// get the method parameters
				if( !( errorCode = parseMethodParameters( scope, stack, params ) ) ) {
					// create the method signature
					signature = generateSignature( name, params );

					// create the method
					printf( "CodeParser::parseMethod - method '%s' signature = '%s' modifiers = %s\n", name, signature, toBinary( this->modifiers ) );
					method = new Method( scope, name, signature, type, this->modifiers );
				}

				// reset the modifier for the current scope
				this->modifiers = 0;
				break;

			// step 2: process the method code block
			case 2:
				// must be a code block
				if( stack->peek()->getType() != tok::CODE_BLOCK ) {
					SYNTAX_ERROR( "symbol '{' expected", stack->next() );
					return NULL;
				}

				// process the method code block
				errorCode = parse( method, ((ComplexToken*)stack->next())->getChildren() );
				method->getCodeBuffer()->putInstruction( RET << A_OP ); // RET
				done = true;
				break;
		}
	}

	// is there already an error code?
	if( errorCode ) {
		return errorCode;
	}

	// did it complete?
	if( !done ) {
		SYNTAX_ERROR( "unexpected end of statement", stack->last() );
		return -1;
	}

	// add the method to the scope
	if( scope->getScopeType() != CLASS_SCOPE ) {
		SYNTAX_ERROR( "method cannot be defined here", stack->last() );
		return -1;
	}

	// add the method to the scope
	ScopeContainer* container = (ScopeContainer*)scope;
	container->addMethod( method );
	return 0;
}