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* [Bug tree-optimization/94934] New: Failure to inline addv
@ 2020-05-03 11:08 gabravier at gmail dot com
  2020-05-04  6:47 ` [Bug target/94934] " rguenth at gcc dot gnu.org
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: gabravier at gmail dot com @ 2020-05-03 11:08 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94934

            Bug ID: 94934
           Summary: Failure to inline addv
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

int f(int x, int y)
{
    return x + y;
}

With -O3 -ftrapv, LLVM outputs this :

f(int, int): # @f(int, int)
  mov eax, edi
  add eax, esi
  jo .LBB0_1
  ret
.LBB0_1:
  ud2

GCC outputs this :

f(int, int):
  sub rsp, 8
  call __addvsi3
  add rsp, 8
  ret

`-ftrapv` may not be specifically intended for speed, but it seems to make
sense to inline it on targets that have direct support for the instructions it
uses.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/94934] Failure to inline addv
  2020-05-03 11:08 [Bug tree-optimization/94934] New: Failure to inline addv gabravier at gmail dot com
@ 2020-05-04  6:47 ` rguenth at gcc dot gnu.org
  2020-05-06 14:52 ` jakub at gcc dot gnu.org
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu.org @ 2020-05-04  6:47 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94934

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |x86_64-*-*
          Component|tree-optimization           |target

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
It's up to targets to decide but as was said in another bug -ftrapv hasn't seen
much love (and wants re-implementation).

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/94934] Failure to inline addv
  2020-05-03 11:08 [Bug tree-optimization/94934] New: Failure to inline addv gabravier at gmail dot com
  2020-05-04  6:47 ` [Bug target/94934] " rguenth at gcc dot gnu.org
@ 2020-05-06 14:52 ` jakub at gcc dot gnu.org
  2020-05-18  8:34 ` gabravier at gmail dot com
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: jakub at gcc dot gnu.org @ 2020-05-06 14:52 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94934

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Yeah, -ftrapv should just be reimplemented using the ubsan/__builtin_*_overflow
internal functions or perhaps killed altogether, one can use
-fsanitize=signed-integer-overflow -fsanitize-undefined-trap-on-error instead.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/94934] Failure to inline addv
  2020-05-03 11:08 [Bug tree-optimization/94934] New: Failure to inline addv gabravier at gmail dot com
  2020-05-04  6:47 ` [Bug target/94934] " rguenth at gcc dot gnu.org
  2020-05-06 14:52 ` jakub at gcc dot gnu.org
@ 2020-05-18  8:34 ` gabravier at gmail dot com
  2020-05-18  9:32 ` jakub at gcc dot gnu.org
  2021-08-03  3:22 ` pinskia at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: gabravier at gmail dot com @ 2020-05-18  8:34 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94934

--- Comment #3 from Gabriel Ravier <gabravier at gmail dot com> ---
In that case, it looks really easy to reimplemnet `-ftrapv` as literally just
enabling `-fsanitize=signed-integer-overflow
-fsanitize-undefined-trap-on-error`.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/94934] Failure to inline addv
  2020-05-03 11:08 [Bug tree-optimization/94934] New: Failure to inline addv gabravier at gmail dot com
                   ` (2 preceding siblings ...)
  2020-05-18  8:34 ` gabravier at gmail dot com
@ 2020-05-18  9:32 ` jakub at gcc dot gnu.org
  2021-08-03  3:22 ` pinskia at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: jakub at gcc dot gnu.org @ 2020-05-18  9:32 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94934

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Gabriel Ravier from comment #3)
> In that case, it looks really easy to reimplemnet `-ftrapv` as literally
> just enabling `-fsanitize=signed-integer-overflow
> -fsanitize-undefined-trap-on-error`.

It shouldn't be literally that, because -ftrapv should be able to coexist with
other UBSan sanitizers (just not signed-integer-overflow) and e.g. let the
other UBSan sanitizers have different decision on what to do on error (the
trap. vs. fatal error vs. just diagnostics and continue).
And for -ftrapv we should consider using the library functions rather than
emitting code inline if it would be too large to match past behavior.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/94934] Failure to inline addv
  2020-05-03 11:08 [Bug tree-optimization/94934] New: Failure to inline addv gabravier at gmail dot com
                   ` (3 preceding siblings ...)
  2020-05-18  9:32 ` jakub at gcc dot gnu.org
@ 2021-08-03  3:22 ` pinskia at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-08-03  3:22 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94934

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

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

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Dup of bug 101521.

*** This bug has been marked as a duplicate of bug 101521 ***

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2021-08-03  3:22 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-05-03 11:08 [Bug tree-optimization/94934] New: Failure to inline addv gabravier at gmail dot com
2020-05-04  6:47 ` [Bug target/94934] " rguenth at gcc dot gnu.org
2020-05-06 14:52 ` jakub at gcc dot gnu.org
2020-05-18  8:34 ` gabravier at gmail dot com
2020-05-18  9:32 ` jakub at gcc dot gnu.org
2021-08-03  3:22 ` pinskia at gcc dot gnu.org

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