RE: [discuss] semantics, "replay debugging" vs. "reverse debugging"

Dave Korn
2008-10-22T17:09:48Z

teawater wrote on 22 October 2008 17:43:

> Sorry I am wrong.
> In ARM, Just adds set cpsr reg. So:
> add r0,r0,#10
> Can reverse without record too.

Your examples are too limited to be of practical use; almost every
instruction executed destroys information.

It's easy to reverse "add r0,r0,#10" by subtracting 10 from r0. But how do
you reverse "add r0,r1,#10", or anything else where the source and dest
register are different? The original value of r0 is gone without trace, and
r1 was not changed by the instruction!

cheers,
DaveK
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