jk@plx.UUCP (jk) (06/14/84)
I am interested in hearing about solutions others have used for instruction restarts on 68000's. My current "challange" is the Bourne shell and the way it catches SIGSEGV's and sbrk()'s to grow its data space. We currently have code in our kernel that tries to match the saved instruction register with some number of instructions before the (bogus) saved pc. This works in most cases, like automatic stack extension. It fails miserably if it finds the right opcode but it is not the correct instruction or it is not the opcode field of an instruction. In the case of the sh this is disaterous as the sh blindly sbrk()'s more space, returns from the signal catching code to re-execute the wrong instruction again, sbrk()'s for more space.....boom, boom out go the lights. Has anyone got a good solution for this problem? Thanks in advance, (no cute signoff yet) jk ..!decvax!sun!plx!jk
jec@iuvax.UUCP (06/20/84)
I would also be interested in possible solutions to the problem. I am
especially interested if someone knows of a way to restart the "move
multiple registers" command since there is pretty much no way that I
know of to determine where the instruction failed.
--
James Conley
Indiana University
68K Education Board Project
...{isrnix|iuvax}!jec