This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: support single predicate set instructions in GCC-4.1.1
2007/9/26, Jim Wilson <wilson@specifix.com>:
> On Tue, 2007-09-25 at 15:13 +0800, 吴曦 wrote:
> > propagate_one_insn), I don't understand why GCC fails the computation
> > of liveness if there is no optimization flag :-(.
>
> There is probably something else happening with -O that is recomputing
> some liveness or CFG info. For instance, the flow2 pass will call
> split_all_insns and cleanup_cfg, but only with -O. You could try
> selectively disabling other optimization passes to determine which one
> is necessary in order for your code to work. Actually, looking closer,
> I see several of them call update_life_info. regrename for instance has
> two update_life_info calls.
>
> Another possibility here is to try calling recompute_reg_usage instead
> of doing it yourself. Or maybe calling just update_life_info directly,
> if you need different flags set.
>
> FYI This stuff is all different on mainline since the dataflow merge.
> I'm assuming you are using gcc-4.2.x.
> --
> Jim Wilson, GNU Tools Support, http://www.specifix.com
>
>
>
Thanks, it's the problem of pass_stack_adjustments.