On Tue, Aug 19, 2014 at 8:46 PM, Wei Mi <w...@google.com> wrote:
> Sorry for the late reply. I took some time to make myself more
> familiar with NORETURN and related code, and finally I understood what
> you mean and saw why only GF_CALL_CTRL_ALTERING was enough and
> GF_CALL_NORETURN was unneeded. With your suggestion, the change looks
> much briefer! Please check if the new patch attached is ok.
Indeed - much nicer than I originally thought. Thanks for bearing
with me.
> bootstrap and regression tests pass on x86_64-linux-gnu.
Ok!
Thanks,
Richard.
> Thanks,
> Wei.
>
>> +static void
>> +update_no_abnormal_goto_attr (basic_block bb)
>> +{
>> + gimple_stmt_iterator gsi;
>> + for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
>> + {
>>
>> it should be enough to check these on last stmts of a basic block, no?
>
> Yes, that is better.
>
>>
>> That you call update_no_abnormal_goto_attr from two places
>> before cleanup_tree_cfg_bb suggests you may want to perform
>> this change in cleanup_control_flow_bb which already looks
>> at the last stmt only?
>
> Changed.
>
>>
>> Btw, I originally had this whole idea of moving flags to the gimple
>> stmt level because of the "interesting" way we handle the noreturn
>> attribute (calls to noreturn functions also end basic-blocks).
>>
>> Thus would it be possible to turn all these into a single flag,
>> GF_CALL_CTRL_ALTERING? That is, cover everything
>> that is_ctrl_altering_stmt covers? I suggest we initialize it at
>> CFG build time and only ever clear it later.
>
> Good idea!
