Re: [PATCH 1/N] Clean-up usage of ipa_fn_summary and ipa_call_summary summaries.

[Jan Hubicka <hubicka at ucw dot cz>]

> Hello.
> 
> ICEs on:
> 
> $ cat ice.ii
> #pragma GCC optimize 0
> int main() {}
> 
> $ ./xgcc -B. -O2 ice.ii
> during IPA pass: cp
> ice.ii:2:13: internal compiler error: Segmentation fault
>  int main() {}
>              ^
> 0xdbb6bf crash_signal
> 	/home/marxin/Programming/gcc/gcc/toplev.c:324
> 0x7ffff6d8ba6f ???
> 	/usr/src/debug/glibc-2.27-5.1.x86_64/signal/../sysdeps/unix/sysv/linux/x86_64/sigaction.c:0
> 0x15edd82 ipcp_propagate_stage
> 	/home/marxin/Programming/gcc/gcc/ipa-cp.c:3292
> 0x15f049a ipcp_driver
> 	/home/marxin/Programming/gcc/gcc/ipa-cp.c:5081
> 0x15f049a execute
> 	/home/marxin/Programming/gcc/gcc/ipa-cp.c:5172

I see, it would be cleaner to simply skip !optimize functions in this loop
(and not try to allocate lattices for them), but that is definitly something
for followup.

> >> @@ -1199,7 +1199,8 @@ sem_function::merge (sem_item *alias_item)
> >>  		     "can not create wrapper of stdarg function.\n");
> >>  	}
> >>        else if (ipa_fn_summaries
> >> -	       && ipa_fn_summaries->get_create (alias)->self_size <= 2)
> >> +	       && ipa_fn_summaries->get (alias) != NULL
> >> +	       && ipa_fn_summaries->get (alias)->self_size <= 2)
> > 
> > Alias is the target we merge to. In what sictuation it can be unanalyzed?
> 
> Can't that also ICE for similar reason as IPA CP?

Hmm, I do not think we should try to merge -O0 functions :)
But again, if you have testcase that triggers this path, we could
handle it later.

Thanks! Patch is OK with keeping those two hunks after the
remaining few changes.
Honza