* [Bug rtl-optimization/85390] possible missed optimisation / regression from 6.3 with conditional expression
[not found] <bug-85390-4@http.gcc.gnu.org/bugzilla/>
@ 2021-07-20 0:55 ` pinskia at gcc dot gnu.org
2021-12-16 7:01 ` [Bug tree-optimization/85390] [9/10/11/12 Regression] " pinskia at gcc dot gnu.org
` (5 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-07-20 0:55 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85390
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
More likely we don't normally pull loads above conditionals at all especially
when there is one on each side.
Doing this:
extern int a, b, c;
int f(int x, int b, int a)
{
__builtin_prefetch((void *) (x ? a : b));
return c;
}
Shows that.
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/85390] [9/10/11/12 Regression] possible missed optimisation / regression from 6.3 with conditional expression
[not found] <bug-85390-4@http.gcc.gnu.org/bugzilla/>
2021-07-20 0:55 ` [Bug rtl-optimization/85390] possible missed optimisation / regression from 6.3 with conditional expression pinskia at gcc dot gnu.org
@ 2021-12-16 7:01 ` pinskia at gcc dot gnu.org
2022-01-21 13:50 ` rguenth at gcc dot gnu.org
` (4 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-12-16 7:01 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85390
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to fail| |7.1.0
Last reconfirmed| |2021-12-16
Target Milestone|--- |9.5
Keywords| |needs-bisection
Ever confirmed|0 |1
Summary|possible missed |[9/10/11/12 Regression]
|optimisation / regression |possible missed
|from 6.3 with conditional |optimisation / regression
|expression |from 6.3 with conditional
| |expression
CC| |pinskia at gcc dot gnu.org
Status|UNCONFIRMED |NEW
Component|rtl-optimization |tree-optimization
Known to work| |6.4.0
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Ok, the issue is just dumb luck:
Take:
extern int a, b, c;
int f(int x)
{
__builtin_prefetch((void *) (__SIZE_TYPE__)(x ? a : b));
return c;
}
int f1(int x)
{
int t = x ? a :b;
__builtin_prefetch((void *)(__SIZE_TYPE__)t);
return c;
}
The f1 uses cmov while f does not.
The gimple level difference is there is two cast (one in each branch) for f
while only one cast outside of the PHI node.
But that was that way even in GCC 6.
I wonder what changed in GCC 7 which caused this issue to appear.
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/85390] [9/10/11/12 Regression] possible missed optimisation / regression from 6.3 with conditional expression
[not found] <bug-85390-4@http.gcc.gnu.org/bugzilla/>
2021-07-20 0:55 ` [Bug rtl-optimization/85390] possible missed optimisation / regression from 6.3 with conditional expression pinskia at gcc dot gnu.org
2021-12-16 7:01 ` [Bug tree-optimization/85390] [9/10/11/12 Regression] " pinskia at gcc dot gnu.org
@ 2022-01-21 13:50 ` rguenth at gcc dot gnu.org
2022-01-31 14:45 ` marxin at gcc dot gnu.org
` (3 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-01-21 13:50 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85390
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Priority|P3 |P2
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/85390] [9/10/11/12 Regression] possible missed optimisation / regression from 6.3 with conditional expression
[not found] <bug-85390-4@http.gcc.gnu.org/bugzilla/>
` (2 preceding siblings ...)
2022-01-21 13:50 ` rguenth at gcc dot gnu.org
@ 2022-01-31 14:45 ` marxin at gcc dot gnu.org
2022-05-27 9:38 ` [Bug tree-optimization/85390] [10/11/12/13 " rguenth at gcc dot gnu.org
` (2 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: marxin at gcc dot gnu.org @ 2022-01-31 14:45 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85390
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |marxin at gcc dot gnu.org
Keywords|needs-bisection |
--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
> But that was that way even in GCC 6.
> I wonder what changed in GCC 7 which caused this issue to appear.
Changed with r7-2128-gebe8f3226c941730
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/85390] [10/11/12/13 Regression] possible missed optimisation / regression from 6.3 with conditional expression
[not found] <bug-85390-4@http.gcc.gnu.org/bugzilla/>
` (3 preceding siblings ...)
2022-01-31 14:45 ` marxin at gcc dot gnu.org
@ 2022-05-27 9:38 ` rguenth at gcc dot gnu.org
2022-06-28 10:35 ` jakub at gcc dot gnu.org
2023-05-30 7:41 ` [Bug tree-optimization/85390] [10/11/12/13/14 " pinskia at gcc dot gnu.org
6 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-05-27 9:38 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85390
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|9.5 |10.4
--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 9 branch is being closed
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/85390] [10/11/12/13 Regression] possible missed optimisation / regression from 6.3 with conditional expression
[not found] <bug-85390-4@http.gcc.gnu.org/bugzilla/>
` (4 preceding siblings ...)
2022-05-27 9:38 ` [Bug tree-optimization/85390] [10/11/12/13 " rguenth at gcc dot gnu.org
@ 2022-06-28 10:35 ` jakub at gcc dot gnu.org
2023-05-30 7:41 ` [Bug tree-optimization/85390] [10/11/12/13/14 " pinskia at gcc dot gnu.org
6 siblings, 0 replies; 7+ messages in thread
From: jakub at gcc dot gnu.org @ 2022-06-28 10:35 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85390
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|10.4 |10.5
--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 10.4 is being released, retargeting bugs to GCC 10.5.
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/85390] [10/11/12/13/14 Regression] possible missed optimisation / regression from 6.3 with conditional expression
[not found] <bug-85390-4@http.gcc.gnu.org/bugzilla/>
` (5 preceding siblings ...)
2022-06-28 10:35 ` jakub at gcc dot gnu.org
@ 2023-05-30 7:41 ` pinskia at gcc dot gnu.org
6 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-05-30 7:41 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85390
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to work| |14.0
Target Milestone|10.5 |14.0
Status|NEW |RESOLVED
Resolution|--- |FIXED
--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed fully for GCC 14 by r14-573-g69f1a8af45d8a4 which pulls out the cast from
the branches and allows ifcvt to happen.
^ permalink raw reply [flat|nested] 7+ messages in thread