[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025 Richard Biener changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED --- Comment #8 from Richard Biener --- Fixed.
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025
--- Comment #7 from CVS Commits ---
The master branch has been updated by Richard Biener :
https://gcc.gnu.org/g:b6ff3ddecfa93d53867afaaa078f85fc848abbbd
commit r11-272-gb6ff3ddecfa93d53867afaaa078f85fc848abbbd
Author: Richard Biener
Date: Fri May 8 12:03:30 2020 +0200
tree-optimization/94988 - enhance SM some more
This enhances store-order preserving store motion to handle the case
of non-invariant dependent stores in the sequence of unconditionally
executed stores on exit by re-issueing them as part of the sequence
of stores on the exit. This fixes the observed regression of
gcc.target/i386/pr64110.c which relies on store-motion of 'b'
for a loop like
for (int i = 0; i < j; ++i)
*b++ = x;
where for correctness we now no longer apply store-motion. With
the patch we emit the correct
tem = b;
for (int i = 0; i < j; ++i)
{
tem = tem + 1;
*tem = x;
}
b = tem;
*tem = x;
preserving the original order of stores. A testcase reflecting
the miscompilation done by earlier GCC is added as well.
This also fixes the reported ICE in PR95025 and adds checking code
to catch it earlier - the issue was not-supported refs propagation
leaving stray refs in the sequence.
2020-05-11 Richard Biener
PR tree-optimization/94988
PR tree-optimization/95025
* tree-ssa-loop-im.c (seq_entry): Make a struct, add from.
(sm_seq_push_down): Take extra parameter denoting where we
moved the ref to.
(execute_sm_exit): Re-issue sm_other stores in the correct
order.
(sm_seq_valid_bb): When always executed, allow sm_other to
prevail inbetween sm_ord and record their stored value.
(hoist_memory_references): Adjust refs_not_supported propagation
and prune sm_other from the end of the ordered sequences.
* gcc.dg/torture/pr94988.c: New testcase.
* gcc.dg/torture/pr95025.c: Likewise.
* gcc.dg/torture/pr95045.c: Likewise.
* g++.dg/asan/pr95025.C: New testcase.
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025
--- Comment #6 from David Binderman ---
My creduced version is similar:
static a;
short b;
*c;
d() {
for (;; a--)
for (; b; b++) {
*c = 5;
if (a)
return;
}
}
Flag -O2 on x86_64 required. The code seems to compile ok
on the raspberry pi.
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025
--- Comment #5 from Martin Liška ---
$ cat pr95025.c
static int a;
short b;
int *c;
void d() {
for (;; a -= 1)
for (; b; b += 1) {
*c ^= 5;
if (a)
return;
}
}
$ gcc -O2 -c pr95025.c -Werror
during GIMPLE pass: lim
pr95025.c: In function ‘d’:
pr95025.c:4:6: internal compiler error: Segmentation fault
4 | void d() {
| ^
0xe36b0f crash_signal
/home/marxin/Programming/gcc/gcc/toplev.c:328
0x778fef1f ???
/usr/src/debug/glibc-2.31-4.1.x86_64/signal/../sysdeps/unix/sysv/linux/x86_64/sigaction.c:0
0x72dd2c execute_sm_exit
/home/marxin/Programming/gcc/gcc/tree-ssa-loop-im.c:2224
0xf71d25 hoist_memory_references
/home/marxin/Programming/gcc/gcc/tree-ssa-loop-im.c:2562
0xf71d25 store_motion_loop
/home/marxin/Programming/gcc/gcc/tree-ssa-loop-im.c:2824
0xf70a21 store_motion_loop
/home/marxin/Programming/gcc/gcc/tree-ssa-loop-im.c:2830
0xf72cca store_motion
/home/marxin/Programming/gcc/gcc/tree-ssa-loop-im.c:2845
0xf72cca tree_ssa_lim
/home/marxin/Programming/gcc/gcc/tree-ssa-loop-im.c:3065
0xf72cca execute
/home/marxin/Programming/gcc/gcc/tree-ssa-loop-im.c:3115
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025 --- Comment #4 from Martin Liška --- (In reply to David Binderman from comment #3) > Created attachment 48504 [details] > C source code I'm gonna reduce that.
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025 --- Comment #3 from David Binderman --- Created attachment 48504 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48504=edit C source code
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025 --- Comment #2 from Richard Biener --- (In reply to David Binderman from comment #1) > I see this bug also. Another C test case is available on request. Please attach it.
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025 Richard Biener changed: What|Removed |Added Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org Status|NEW |ASSIGNED
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025 David Binderman changed: What|Removed |Added CC||dcb314 at hotmail dot com --- Comment #1 from David Binderman --- I see this bug also. Another C test case is available on request.
[Bug regression/95025] [11 Regression] ICE in execute_sm_exit at gcc/tree-ssa-loop-im.c:2224 since r11-161-g283cb9ea6293e813
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95025 Martin Liška changed: What|Removed |Added Known to work||10.1.0 Version|10.0|11.0 Ever confirmed|0 |1 Status|UNCONFIRMED |NEW Known to fail||11.0 Last reconfirmed||2020-05-09 Target Milestone|--- |11.0
