On Tue, 2003-01-28 at 14:48, Mike Uhler wrote:
> If the patch assumes that one can look backward by one instruction
> in the STATIC code to determine if the instruction is in a
> delay slot, one can not have code that jumps directly to the
> instruction following another branch, as this would cause the
> code to assume that it was in the delay slot of the branch.
A while back, when working on a different architecture that also had
branch delay slots, it took me a while to get my head around the
branch-in-a-delay-slot case, e.g.
10: b 100
20: b 30
where the actual program flow would be
and instruction 100 would be considered to be in the delay slot of 20.
I was *very* happy when I first looked at MIPS to see that this was
specified as unpredictable, even if it was pretty cool to be able to
make the CPU execute a single instruction in the middle of nowhere.
Pointless, but cool. :)