Il 02/04/2013 19:17, Peter Maydell ha scritto: > On 2 April 2013 17:56, Paolo Bonzini <pbonz...@redhat.com> wrote: >> Il 02/04/2013 18:43, Peter Maydell ha scritto: >>> Doesn't this incorrectly set the long alignment to 8 >>> for ppc64abi32? (Probably similar problem for >>> sparc32plus and mipsn32. The underlying point here is that >>> alignment is an ABI decision and you can have more than one >>> ABI for a particular TARGET_FOO.) >> >> Hmm, seems like you're right _but_ I am not sure if the *current* code >> is correct. On real hardware, the CPUs are certainly not able to do >> unaligned 32-bit accesses, and target_long/target_ulong pointers look >> like they're never used for data that comes from target memory. > > Did you check linux-user too? I'm pretty sure we have structs > and so on that mirror target memory and use target_ulong. > >> What these targets want to have 32-bit alignment is really >> abi_long/abi_ulong, and that's already okay. Alex, Blue, Aurelien, >> can you test the above three targets? > > Mmm, rather than speculating we should just confirm what gcc > thinks the alignment of void* should be on these targets > (since "a thing the size of a pointer" is what target_long/ulong > represent, I think.)
I think "a thing the size of a pointer" should be abi_long/ulong. The pointer is not a CPU concept. > That said, we should keep bugfixes and cleanup patches separated, Indeed. The change was unintended, and your comment is worth a respin. > so on approach for proceeding with these cleanup patches is just > to define TARGET_LONG_ALIGNMENT based on TARGET_ABI32 or whatever is > appropriate for each target CPU. Then we retain the same behaviour. Yes, TARGET_ABI32. I'll have to squash patches 1 and 2, and the testing RFH still holds because this alignment things sounds fishy... Paolo
