> Sorry for the slow response. Jeff has approved the patch in the > meantime, but I didn't want to go ahead and apply it while there > was still disagreement...
I still think that it isn't appropriate to short-circuit the main computation as the patch does, but I don't want to block it after Jeff's approval. > (1) we have a non-paradoxical subreg; > (2) both (reg:ymode xregno) and (reg:xmode xregno) occupy full > hard registers (no padding or unused upper bits); > (3) (reg:ymode xregno) and (reg:xmode xregno) store the same number > of bytes (X) in each constituent hard register; > (4) the offset is a multiple of X, i.e. the data we're accessing > is aligned to a register boundary; and > (5) endianness is regular (no differences between words and bytes, > or between registers and memory) OK, that's a nice translation of the new code. :-) It seems to me that the patch wants to extend the support of generic subregs to modes whose sizes are not multiple of each other, which is a requirement of the existing code, but does that in a very specific case for the sake of the ARM port without saying where all the above restrictions come from. -- Eric Botcazou
