On Wed, Nov 19, 2014 at 5:35 PM, H.J. Lu <hjl.to...@gmail.com> wrote: > On Wed, Nov 19, 2014 at 5:23 PM, Andrew Pinski <pins...@gmail.com> wrote: >> On Wed, Nov 19, 2014 at 5:11 PM, H.J. Lu <hjl.to...@gmail.com> wrote: >>> On Wed, Nov 19, 2014 at 4:54 PM, Andrew Pinski <pins...@gmail.com> wrote: >>>> Hi, >>>> For ILP32 on AARCH64, we have ptr_mode != Pmode (we have ptr_mode >>>> being SImode while Pmode is DImode and POINTER_SIZE is 32). This >>>> breaks ipa-polymorphic-call assumption that Pmode is the correct mode >>>> for pointers. Right now before this patch we get many testcase >>>> failures in the C++ testsuite due to this. Some of the tests fail due >>>> to the wrong devirtualization happening (using the base class rather >>>> the current class). >>>> >>>> This patch fixes the issue by using POINTER_SIZE in place of >>>> GET_MODE_BITSIZE (Pmode) all over the file. >>>> >>>> OK? Bootstrapped and tested on x86_64 and cross built and tested for >>>> aarch64-elf with no regressions. >>>> >>>> Thanks, >>>> Andrew Pinski >>>> >>>> ChangeLog: >>>> ipa/63981 >>>> * ipa-polymorphic-call.c (possible_placement_new): >>>> Use POINTER_SIZE instead of GET_MODE_BITSIZE (Pmode). >>>> (ipa_polymorphic_call_context::restrict_to_inner_class): Likewise. >>>> (extr_type_from_vtbl_ptr_store): Likewise. >>> >>> Does Pmode affect class layout? >> >> No only POINTER_SIZE. ILP32 is one of the few ABIs where Pmode != >> ptr_mode (sizeof(ptr_mode) == POINTER_SIZE always). >> >> x32 has a similar issue with -maddress-mode=long but the default for >> x32 is -maddress-mode=short. > > Pmode shouldn't change class layout, which is determined by ptr_mode. > You can mix object files compiled by -maddress-mode=long with > -maddress-mode=short. Do those tests fail with -maddress-mode=long > under x32?
I suspect they do fail with -maddress-mode=long but I did not try as I don't have x32 testing setup right now. Thanks, Andrew > > -- > H.J.
