Stackrahmens

Stackrahmen, or stack frames, are data structures created on the call stack when a function or subroutine is invoked. Each frame encapsulates the information needed to transfer control back to the caller and to store the callee’s local data during execution. The frame typically includes the return address, saved registers, the previous frame pointer, and space for parameters and local variables.

Contents typically include: the return address; the old frame pointer; saved callee-saved registers; local variables and temporary storage; arguments passed on the stack; and alignment padding to meet ABI requirements. The exact layout varies by architecture and calling convention.

Creation and destruction: On function entry, the prologue adjusts the stack pointer to allocate the frame, saves registers, and may set up a frame pointer. On function exit, the epilogue restores saved registers and deallocates the frame, returning via the saved address. Some ABIs use a frame pointer, others permit frame-pointer elimination and use SP-relative addressing.

Stack frames are central to debugging and exception handling. They enable stack unwinding to reconstruct the call sequence after a fault. They also constrain resources: excessive recursion or deep calls risk stack overflow, mitigated by guards, canaries, and larger stack limits.

In practice, the exact structure of a stack frame depends on the programming language, compiler, and hardware architecture. Understanding stack frames is important for low-level programming, performance analysis, and systems debugging.