DATA PROCESSOR TRACING HISTORY OF SUBROUTINE

摘要

PURPOSE:To provide a data processor which can stores the history regarding a subroutine with a small overhead. CONSTITUTION:When subroutines are called, return addresses A, B, and C of call sources are stored in stack positions which 1st and 2nd stack pointers 10 and 20 indicate, respectively. The data processor gives a transfer instruction to a transfer means 60 at need in the execution of the program and indicates a buffer 70 for history storage to which the transfer means should transfer the return addresses at a time. The transfer means transfers the return addresses stored in the 2nd stack area 20 to the indicated buffer for history storage at a time over the range that the 2nd stack pointer indicates. The history of the subroutine is made clear by tracking the batch-transferred addresses.