[Bug rtl-optimization/60776] [4.9 Regression] FAIL gcc.dg/builtin-bswap-6.c and gcc.dg/builtin-bswap-7.c

["rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60776

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |krebbel at gcc dot gnu.org

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Andreas, that's very likely caused by your change to the testcase.  For some
reason I see two adjacent

(insn 11 10 28 2 (set (reg:CCZ 17 flags)
        (compare:CCZ (reg:SI 84 [ D.1826 ])
            (reg:SI 85 [ D.1826 ])))
/space/rguenther/src/svn/trunk/gcc/testsuite/gcc.dg/builtin-bswap-6.c:37 7
{*cmpsi_1}
     (expr_list:REG_UNUSED (reg:CCZ 17 flags)
        (nil)))
(insn 28 11 29 2 (set (reg:CCZ 17 flags)
        (compare:CCZ (reg:SI 84 [ D.1826 ])
            (reg:SI 85 [ D.1826 ])))
/space/rguenther/src/svn/trunk/gcc/testsuite/gcc.dg/builtin-bswap-6.c:39 7
{*cmpsi_1}
     (expr_list:REG_DEAD (reg:SI 85 [ D.1826 ])
        (expr_list:REG_DEAD (reg:SI 84 [ D.1826 ])
            (nil))))

and thus the bswaps are no longer single-use.  Eventually we relied on
if-conversion doing some magic here which the testcase change disabled?