leave

rsp = rbp
pop rbp

The leave instruction is a convenient way to restore rbp and rsp before returning from a function with a normal stack frame.

With a stack frame established using

my_function:
        push    rbp             ; save previous rbp
        mov     rbp, rsp        ; establish frame pointer
                                ; rbp will be used to access local variables
                                ; and non-register parameters to my_function
        sub     rsp, N          ; N is some multiple of 16
                                ; leaving space for local variables and
                                ; non-register parameters for called functions

Use leave to return using

        leave                   ; restores rbp and rsp
        ret                     ; returns to the calling function

flags: none