[Bug target/104200] New: [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[Bug target/104200] New: [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

            Bug ID: 104200
           Summary: [12 Regression] FAIL:
                    gcc.target/aarch64/atomic-inst-cas.c (test for excess
                    errors) fails
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: testsuite-fail
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---
            Target: aarch64

+FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors)
/home/ubuntu/src/upstream-gcc-aarch64/gcc/gcc/testsuite/gcc.target/aarch64/atomic-inst-cas.c:
In function 'test_cas_atomic_relaxed_consume_char':^M
/home/ubuntu/src/upstream-gcc-aarch64/gcc/gcc/testsuite/gcc.target/aarch64/atomic-inst-cas.c:22:12:
warning: failure memory model 'memory_order_consume' cannot be stronger than
success memory model 'memory_order_relaxed' for '__atomic_compare_exchange_1'
[-Winvalid-memory-model]^M
....

Most likely caused by r12-6216.

[Bug target/104200] [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0

[Bug testsuite/104200] [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
           Assignee|unassigned at gcc dot gnu.org      |pinskia at gcc dot gnu.org
   Last reconfirmed|                            |2022-01-27
             Status|UNCONFIRMED                 |ASSIGNED

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I am going to fix this testcase.
The warning is expected, the code does check at runtime not to invoke
__atomic_compare_exchange_n with invalid orderings.

    /* The success memory ordering must be at least as strong as        \
       the failure memory ordering.  */                                 \
    if (model_s < model_f)                                              \
      return 0;                                                         \
    /* Ignore invalid memory orderings.  */                             \
    if (model_f == __ATOMIC_RELEASE || model_f == __ATOMIC_ACQ_REL)     \
      return 0;                                                         \

I am trying to decide I just want to add -Wno-invalid-memory-model or add the
dg-warning . I am leaning towards adding the flag.

[Bug tree-optimization/104200] [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|testsuite                   |tree-optimization

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Wait this should not warn as __atomic_compare_exchange_n should have been
removed before the warning happens as it is happening in
pass_waccess::check_atomic_builtin now which should have been after the code
was removed ...

Let me try to reduce a testcase and all.

[Bug tree-optimization/104200] [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |NEW
           Assignee|pinskia at gcc dot gnu.org         |unassigned at gcc dot gnu.org
           Keywords|                            |diagnostic

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
waccess is way early where there is almost no optimizations happen.
Not going to fix this.
Simple testcase:
int test_cas_atomic_relaxed_consume_char (char* val, char* foo, char* bar) {
 int model_s = 0;
 int model_f = 1;
 if (model_s < model_f) return 0;
 if (model_f == 3 || model_f == 4) return 0;
 return __atomic_compare_exchange_n (val, foo, bar, 0, model_s, model_f);
}

[Bug tree-optimization/104200] [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=102177

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
As mentioned in PR 102177, maybe we should not be warning about these as they
are valid now in C++17.

[Bug tree-optimization/104200] [12 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Maybe waccess should do a similar thing to uninitialized warnings does now:
https://gcc.gnu.org/pipermail/gcc-patches/2022-February/589983.html

[Bug tree-optimization/104200] [12/13 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|12.0                        |12.2

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 12.1 is being released, retargeting bugs to GCC 12.2.

[Bug tree-optimization/104200] [12/13 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

[Bug tree-optimization/104200] [12/13/14 Regression] FAIL: gcc.target/aarch64/atomic-inst-cas.c (test for excess errors) fails

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104200

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|12.3                        |12.4

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 12.3 is being released, retargeting bugs to GCC 12.4.