[Bug tree-optimization/110365] New: wrong code at -O2 and -O3 on x86_64-linux-gnu

[Bug tree-optimization/110365] New: wrong code at -O2 and -O3 on x86_64-linux-gnu

[zhendong.su at inf dot ethz.ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110365

            Bug ID: 110365
           Summary: wrong code at -O2 and -O3 on x86_64-linux-gnu
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zhendong.su at inf dot ethz.ch
  Target Milestone: ---

It appears to be a recent regression.

Compiler Explorer: https://godbolt.org/z/aP9aMrsGq

[725] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/home/suz/suz-local/software/local/gcc-trunk/bin/../libexec/gcc/x86_64-pc-linux-gnu/14.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk
--enable-sanitizers --enable-languages=c,c++ --disable-werror
--disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 14.0.0 20230622 (experimental) [master r14-924-gd709841ae0f] (GCC) 
[726] % 
[726] % gcctk -O1 small.c; ./a.out
[727] % 
[727] % gcctk -O2 small.c
[728] % ./a.out
Aborted
[729] % 
[729] % cat small.c
int a = 1;
void b() {
  int *c = &a, d = a;
  if (a < -1)
    d = a + d;
  a = d;
  if (a > 0)
    *c = 1;
  int e = -a;
  if (e < a) {
    e = a;
    if (!a)
      __builtin_abort();
  }
  a = e;
}
int main() {
  b();
  if (a != 1)
    __builtin_abort();
  return 0;
}

[Bug tree-optimization/110365] wrong code at -O2 and -O3 on x86_64-linux-gnu

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110365

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---

phiopt match-simplify trying:
        d_6 > 0 ? 1 : e_1
Matching expression match.pd:1990, gimple-match-5.cc:23
Matching expression match.pd:1990, gimple-match-5.cc:23
Applying pattern match.pd:4742, gimple-match-2.cc:16205
Folded into the sequence:
_16 = d_6 > 0;
_8 = (int) _16;
_13 = e_1 | _8;
statement un-sinked:
e_1 = -d_6;
Removing basic block 5
;; basic block 5, loop depth 0
;;  pred:       4
;;  succ:       6

[Bug tree-optimization/110365] wrong code at -O2 and -O3 on x86_64-linux-gnu

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110365

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Duplicate of bug 110252 really.

*** This bug has been marked as a duplicate of bug 110252 ***

[Bug tree-optimization/110365] wrong code at -O2 and -O3 on x86_64-linux-gnu

[zhendong.su at inf dot ethz.ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110365

--- Comment #3 from Zhendong Su <zhendong.su at inf dot ethz.ch> ---
(In reply to Andrew Pinski from comment #2)
> Duplicate of bug 110252 really.
> 
> *** This bug has been marked as a duplicate of bug 110252 ***

Sorry about the dup, and thanks for triaging it.

[Bug tree-optimization/110365] wrong code at -O2 and -O3 on x86_64-linux-gnu

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110365

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Zhendong Su from comment #3)
> Sorry about the dup, and thanks for triaging it.

I really should fix PR 110252 before more different new testcases are produced.