On 6/26/23 11:21, Jan Hubicka wrote:
Hi,
playing with testcases for path isolation and const function, I noticed
that we do not seem to even try to isolate out of range array accesses:
int a[3]={0,1,2};
test(int i)
{
if (i > 3)
return test2(a[i]);
return a[i];
}
Here
Hi,
playing with testcases for path isolation and const function, I noticed
that we do not seem to even try to isolate out of range array accesses:
int a[3]={0,1,2};
test(int i)
{
if (i > 3)
return test2(a[i]);
return a[i];
}
Here call to test2 is dead, since a[i] will acces
> > Also as discussed some time ago, the volatile loads between traps has
> > effect of turning previously pure/const functions into non-const which
> > is somewhat sad, so it is still on my todo list to change it this stage1
> > to something more careful. We discussed internal functions trap_sto
On 6/22/23 07:42, Jan Hubicka wrote:
On 6/22/23 00:31, Richard Biener wrote:
I think there's a difference in that __builtin_trap () is observable
while __builtin_unreachable () is not and reaching __builtin_unreachable
() invokes undefined behavior while reaching __builtin_trap () does not.
>
>
> On 6/22/23 00:31, Richard Biener wrote:
> > I think there's a difference in that __builtin_trap () is observable
> > while __builtin_unreachable () is not and reaching __builtin_unreachable
> > () invokes undefined behavior while reaching __builtin_trap () does not.
> >
> > So the isolatio
On 6/22/23 00:31, Richard Biener wrote:
I think there's a difference in that __builtin_trap () is observable
while __builtin_unreachable () is not and reaching __builtin_unreachable
() invokes undefined behavior while reaching __builtin_trap () does not.
So the isolation code marking the trap
On Wed, 21 Jun 2023, Jeff Law wrote:
>
>
> On 6/21/23 00:41, Richard Biener wrote:
> >> I thought during the introduction of erroneous path isolation that we
> >> concluded stores, calls and such had observable side effects that must be
> >> preserved, even when we hit a block that leads to __bu
On 6/21/23 00:41, Richard Biener wrote:
I thought during the introduction of erroneous path isolation that we
concluded stores, calls and such had observable side effects that must be
preserved, even when we hit a block that leads to __builtin_unreachable.
Indeed, I remember we repeatedly hi
>
> If I manually add a __builtin_unreachable () to the above case
> I see the *(int *)0 = 0; store DSEd. Maybe we should avoid
> removing stores that might trap here? POSIX wise such a trap
> could be a way to jump out of the path leading to unreachable ()
> via siglongjmp ...
I am not sure ho
On Tue, 20 Jun 2023, Jeff Law wrote:
>
>
> On 6/20/23 00:59, Richard Biener via Gcc-patches wrote:
> > DSE isn't good at identifying program points that end lifetime
> > of variables that are not associated with virtual operands. But
> > at least for those that end basic-blocks we can handle th
On 6/20/23 00:59, Richard Biener via Gcc-patches wrote:
DSE isn't good at identifying program points that end lifetime
of variables that are not associated with virtual operands. But
at least for those that end basic-blocks we can handle the simple
case where this ending is in the same basic-
11 matches
Mail list logo
