Unaligned block moves and MEM_ALIGN re-broken

[Richard Kenner]

    The AIX ABI allows doubles to be word-aligned.  According to your
    argument, DFmode values in structures on AIX never should be in FPRs.
    You are changing the semantics of MODE in GCC, which is unacceptable.

No, I'm not.  The criteria for whether something can have an integral
(or FP) mode has *always* been that it has the specified size and the
required alignment.  We may not be doing a very good job in this
discussion of defining what "required" is in all cases, but the
concept is hardly new.

    I ask you again, fix this problem which you have introduced.

I have no idea to what "this problem" refers.

Objects of non-BLKmode certainly can are at known alignments, though it is
possible that there might be a bug in some case of computing what that
alignment is.