------- Comment #3 from dave at hiauly1 dot hia dot nrc dot ca 2010-07-10 23:34 ------- Subject: Re: [4.6 Regression] FAIL: gcc.dg/pr35258.c execution test
On Sat, 10 Jul 2010, rguenth at gcc dot gnu dot org wrote: > I get for all memory accesses an alignment of 8 at expansion time which looks > correct (on i?86). Please debug this a bit, set_mem_attributes_minus_bitpos > looks conservative enough. The rtl in question is the following: (insn 8 6 11 /test/gnu/gcc/gcc/gcc/testsuite/gcc.dg/pr35258.c:16 (set (reg:SI 28 %r28 [orig:94 D.1980 ] [94]) (mem/c:SI (plus:SI (reg/f:SI 1 %r1 [95]) (const_int 1 [0x1])) [0 MEM[(char * {ref-all})&str + 1B]+0 S4 A8])) 37 {*pa.md:2102} (nil)) An alignment of 8 is not sufficient for a 4 byte (SImode) load on targets that define STRICT_ALIGNMENT. We need an alignment of 32. I believe the i?86 hardware allows unaligned addresses, so you wouldn't see the problem. Dave -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44903