> It almost sounds like you need to be preventing the compiler from > considering a lo_sum (whatever) as an offsettable memory address when > the underlying object has had its alignment decreased from its natural > alignment. > > I wouldn't be at all surprised if you do this you won't see the calls > into adjust_address_1 occurring in the first place.
This would be a little heavy handed as the issue only happens in the case where a high part calculation is used by multiple low part calculations. So far I have found that this happens when we have to lower a DI mode load/store into two SI mode load/stores where different offsets are applied to each load/store. I have found a case in the MIPS backend where this occurs, and also when we are expanding a bitfield load/store to RTL, but I am sure there are others. My worry is that it could be hard to track down all cases that generate invalid lo_sums, and therefore it could be easier to just perform the fixup in adjust_address_1. Regards, Andrew
