[Bug rtl-optimization/47614] [4.6 Regression] cpu2000 benchmark 301.apsi fails with revision 169782

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47614

--- Comment #15 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-02-09 21:10:23 UTC ---
Please move the side_effects_p check in reload_cse_simplify_operands right
before the cselib_lookup call, there is no point calling cselib_lookup if it
has side effects.
BTW, on powerpc64-linux Alex's incdec patch apparently broke profiledbootstrap,
cc1 built with -fprofile-use keeps segfaulting on most of libgcc compilations.

A patch similar to #c13 (just with if (side_effects_p (op)) continue; moved
in front of v = cselib_lookup (...);) fixed the profiledbootstrap apparently
(but guess a patch using check_for_inc_dec + the *_operands change will do the
same).  I agree that in this case it can generate better code to delete the
redundant insn and just keep the side effects.