Stack Overflow Detection Using Dedicated Registers

The patent introduces a dedicated stack pointer register that acts as an intermediary between the stack memory and the comparison logic. This register stores the current stack pointer value and automatically compares it with pre-defined minimum and maximum limits, providing overflow protection without requiring complex MMU hardware. The intermediary register simplifies the hardware architecture while maintaining reliable detection of stack boundary violations.

The patent implements continuous stack overflow detection by comparing the stack pointer value with predefined limits after every stack operation. Rather than performing detection only at specific checkpoints (such as after function prologue), the comparison mechanism operates continuously, ensuring that overflow conditions are detected immediately when they occur. This eliminates the need for costly periodic checks while maintaining complete protection coverage throughout program execution.

The patent designs the dedicated stack pointer register to serve multiple functions: it stores the current stack pointer value, enables comparison with minimum and maximum limits, and generates overflow detection signals. By making this register multi-functional, the patent achieves fast detection speed without proportionally increasing device complexity. The same hardware structure supports both normal stack operations and overflow detection, maximizing resource utilization while minimizing additional hardware requirements.