* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
@ 2021-12-13 22:30 ` pinskia at gcc dot gnu.org
2021-12-13 22:51 ` pinskia at gcc dot gnu.org
` (7 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-12-13 22:30 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note the -g is important here.
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
2021-12-13 22:30 ` [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g " pinskia at gcc dot gnu.org
@ 2021-12-13 22:51 ` pinskia at gcc dot gnu.org
2021-12-13 23:02 ` pinskia at gcc dot gnu.org
` (6 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-12-13 22:51 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|--- |12.0
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
2021-12-13 22:30 ` [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g " pinskia at gcc dot gnu.org
2021-12-13 22:51 ` pinskia at gcc dot gnu.org
@ 2021-12-13 23:02 ` pinskia at gcc dot gnu.org
2021-12-14 10:03 ` [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569 marxin at gcc dot gnu.org
` (5 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-12-13 23:02 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
Last reconfirmed| |2021-12-13
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(gdb) p debug_gimple_stmt(stmt)
_67 = _14 + _66;
Before pre had:
intD.9 * __trans_tmp_1D.2946;
....
# RANGE [1, 9223372036854775807] NONZERO 9223372036854775804
_66 = (long unsigned intD.16) _17;
# PT = nonlocal escaped
# ALIGN = 4, MISALIGN = 0
_67 = __trans_tmp_1_14 + _66;
But after:
# RANGE [1, 9223372036854775807] NONZERO 9223372036854775804
_66 = (long unsigned intD.16) _17;
# PT = nonlocal escaped
# ALIGN = 4, MISALIGN = 0
_67 = _14 + _66;
We already removed the definition of _14 too:
Removing dead stmt __trans_tmp_1_14 = _24 + 4;
So it is the order of the removal which is causing issues.
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
` (2 preceding siblings ...)
2021-12-13 23:02 ` pinskia at gcc dot gnu.org
@ 2021-12-14 10:03 ` marxin at gcc dot gnu.org
2021-12-15 20:05 ` acoplan at gcc dot gnu.org
` (4 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: marxin at gcc dot gnu.org @ 2021-12-14 10:03 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |aldyh at gcc dot gnu.org,
| |amacleod at redhat dot com,
| |marxin at gcc dot gnu.org
Summary|[12 Regression] ICE: in |[12 Regression] ICE: in
|build2, at tree.c:4985 with |build2, at tree.c:4985 with
|-g -O2 -fno-tree-dce |-g -O2 -fno-tree-dce
|-fno-tree-dse -fno-tree-fre |-fno-tree-dse -fno-tree-fre
|--param=max-jump-thread-dup |--param=max-jump-thread-dup
|lication-stmts=94 |lication-stmts=94 since
| |r12-2591-g2e96b5f14e402569
--- Comment #3 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r12-2591-g2e96b5f14e402569.
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
` (3 preceding siblings ...)
2021-12-14 10:03 ` [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569 marxin at gcc dot gnu.org
@ 2021-12-15 20:05 ` acoplan at gcc dot gnu.org
2021-12-16 17:17 ` aldyh at gcc dot gnu.org
` (3 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: acoplan at gcc dot gnu.org @ 2021-12-15 20:05 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
Alex Coplan <acoplan at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |acoplan at gcc dot gnu.org
--- Comment #4 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Here's a slightly cleaned up testcase which fails with the same options FWIW:
typedef int *int_ptr;
struct __normal_iterator {
int *_M_current;
__normal_iterator(const int_ptr &__i) : _M_current(__i) {}
void foo() { __normal_iterator(_M_current - 1); }
};
void deallocate(int *);
struct vector {
int *_M_start;
int *_M_finish;
__normal_iterator end() { return _M_finish; }
int back() {
__normal_iterator t = _M_finish;
t.foo();
}
void foo();
};
int *p1, *p2;
int last, result;
void vector::foo() {
for (int i; i;)
while (i) {
__normal_iterator t1 = end();
int *p3, *__old_start = _M_start, *__new_finish;
long __count = &last - __old_start;
if (__count > 0)
__builtin_memmove(&result, __old_start, __count);
p1 = &result + __count;
p2 = p1 + 1;
__count = _M_finish - t1._M_current;
if (__count)
__builtin_memmove(p2, t1._M_current, __count);
p3 = p2 + __count;
__new_finish = p3;
if (__old_start)
deallocate(__old_start);
_M_finish = __new_finish;
back();
}
}
also confirmed on aarch64-linux-gnu.
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
` (4 preceding siblings ...)
2021-12-15 20:05 ` acoplan at gcc dot gnu.org
@ 2021-12-16 17:17 ` aldyh at gcc dot gnu.org
2022-01-04 10:21 ` rguenth at gcc dot gnu.org
` (2 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: aldyh at gcc dot gnu.org @ 2021-12-16 17:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
--- Comment #5 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #2)
> (gdb) p debug_gimple_stmt(stmt)
> _67 = _14 + _66;
>
>
> Before pre had:
> intD.9 * __trans_tmp_1D.2946;
> ....
> # RANGE [1, 9223372036854775807] NONZERO 9223372036854775804
> _66 = (long unsigned intD.16) _17;
> # PT = nonlocal escaped
> # ALIGN = 4, MISALIGN = 0
> _67 = __trans_tmp_1_14 + _66;
>
> But after:
> # RANGE [1, 9223372036854775807] NONZERO 9223372036854775804
> _66 = (long unsigned intD.16) _17;
> # PT = nonlocal escaped
> # ALIGN = 4, MISALIGN = 0
> _67 = _14 + _66;
>
> We already removed the definition of _14 too:
> Removing dead stmt __trans_tmp_1_14 = _24 + 4;
>
> So it is the order of the removal which is causing issues.
Why is PRE removing the DEF of _14 when there are still uses?
<bb 5> [local count: 69834]:
__count.1_62 = (long unsigned int) _11;
__builtin_memmove (_14, _9, __count.1_62);
_66 = (long unsigned int) _17;
_67 = _14 + _66;
...
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
` (5 preceding siblings ...)
2021-12-16 17:17 ` aldyh at gcc dot gnu.org
@ 2022-01-04 10:21 ` rguenth at gcc dot gnu.org
2022-01-04 12:17 ` cvs-commit at gcc dot gnu.org
2022-01-04 12:17 ` rguenth at gcc dot gnu.org
8 siblings, 0 replies; 10+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-01-04 10:21 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Priority|P3 |P1
Status|NEW |ASSIGNED
Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Value numbering stmt = __trans_tmp_1_14 = _24 + 4;
Setting value number of __trans_tmp_1_14 to __trans_tmp_1_22 (changed)
what we do is avoiding useless work during elimination, not visiting if (0)
guarded code - those regions will have not up-to-date SSA form.
Block 14: BB5 found not executable
the issue is that PRE does
/* Because we don't follow exactly the standard PRE algorithm, and decide not
to insert PHI nodes sometimes, and because value numbering of casts isn't
perfect, we sometimes end up inserting dead code. This simple DCE-like
pass removes any insertions we made that weren't actually used. */
simple_dce_from_worklist (inserted_exprs);
which eventually runs into those uses for expressions we inserted into those
unreachable blocks.
The issue is long latent I think.
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
` (6 preceding siblings ...)
2022-01-04 10:21 ` rguenth at gcc dot gnu.org
@ 2022-01-04 12:17 ` cvs-commit at gcc dot gnu.org
2022-01-04 12:17 ` rguenth at gcc dot gnu.org
8 siblings, 0 replies; 10+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2022-01-04 12:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:
https://gcc.gnu.org/g:ebc853deb7cc0487de9ef6e891a007ba853d1933
commit r12-6208-gebc853deb7cc0487de9ef6e891a007ba853d1933
Author: Richard Biener <rguenther@suse.de>
Date: Tue Jan 4 11:59:35 2022 +0100
tree-optimization/103690 - not up-to-date SSA and PRE DCE
This avoids running simple_dce_from_worklist on partially not up-to-date
SSA form (in unreachable code regions) by scheduling CFG cleanup
manually as is done anyway when tail-merging runs.
2022-01-04 Richard Biener <rguenther@suse.de>
PR tree-optimization/103690
* tree-pass.h (tail_merge_optimize): Adjust.
* tree-ssa-tail-merge.c (tail_merge_optimize): Pass in whether
to re-split critical edges, move CFG cleanup ...
* tree-ssa-pre.c (pass_pre::execute): ... here, before
simple_dce_from_worklist and delay freeing inserted_exprs from
...
(fini_pre): .. here.
^ permalink raw reply [flat|nested] 10+ messages in thread* [Bug tree-optimization/103690] [12 Regression] ICE: in build2, at tree.c:4985 with -g -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 since r12-2591-g2e96b5f14e402569
2021-12-13 19:26 [Bug tree-optimization/103690] New: [12 Regression] ICE: in build2, at tree.c:4985 with -O2 -fno-tree-dce -fno-tree-dse -fno-tree-fre --param=max-jump-thread-duplication-stmts=94 zsojka at seznam dot cz
` (7 preceding siblings ...)
2022-01-04 12:17 ` cvs-commit at gcc dot gnu.org
@ 2022-01-04 12:17 ` rguenth at gcc dot gnu.org
8 siblings, 0 replies; 10+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-01-04 12:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103690
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution|--- |FIXED
--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.
^ permalink raw reply [flat|nested] 10+ messages in thread