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* [Bug c/95777] New: Allow specifying more than one target options at the same time in target and target_clones attribute
@ 2020-06-20  5:02 yyc1992 at gmail dot com
  2020-06-22  7:41 ` [Bug c/95777] " rguenth at gcc dot gnu.org
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: yyc1992 at gmail dot com @ 2020-06-20  5:02 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95777

            Bug ID: 95777
           Summary: Allow specifying more than one target options at the
                    same time in target and target_clones attribute
           Product: gcc
           Version: 10.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: yyc1992 at gmail dot com
  Target Milestone: ---

Currently it seems that (document and own tests) only a single option is
allowed for each version of the function using `target` and `target_clones`.
This can be a problem for options that are not strict subset of each other
(e.g. the AVX512 ones IIUC). Of course specifying `cpu=haswell` and
`cpu=skylake` for the same target doesn't make much sense so some checking
should be in place but I believe allowing multiple directly testable features
to be specified at the same time should be allowed.

A related issue is that while one can indeed do some of these by specifying a
`arch=<cpu>`. However, even if the runtime CPU supports all the features it'll
still not get selected if the name doesn't exactly match (tested with
`arch=haswell` on my kabelake laptop). If a fallback could be implemented to
make this work that will be also good enough for me at least...

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

* [Bug c/95777] Allow specifying more than one target options at the same time in target and target_clones attribute
  2020-06-20  5:02 [Bug c/95777] New: Allow specifying more than one target options at the same time in target and target_clones attribute yyc1992 at gmail dot com
@ 2020-06-22  7:41 ` rguenth at gcc dot gnu.org
  2020-06-22 13:33 ` yyc1992 at gmail dot com
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu.org @ 2020-06-22  7:41 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95777

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |marxin at gcc dot gnu.org
             Target|                            |x86_64-*-* i?86-*-*

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I think multiple targets are allowed by means of providing multiple
declarations with different attribute parameters.  Martin?

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

* [Bug c/95777] Allow specifying more than one target options at the same time in target and target_clones attribute
  2020-06-20  5:02 [Bug c/95777] New: Allow specifying more than one target options at the same time in target and target_clones attribute yyc1992 at gmail dot com
  2020-06-22  7:41 ` [Bug c/95777] " rguenth at gcc dot gnu.org
@ 2020-06-22 13:33 ` yyc1992 at gmail dot com
  2020-06-22 14:19 ` yyc1992 at gmail dot com
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: yyc1992 at gmail dot com @ 2020-06-22 13:33 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95777

--- Comment #2 from Yichao Yu <yyc1992 at gmail dot com> ---
I only tested this with `target_clones` and it seems that I misread the
document for `target`. So this is only an issue with `target_clones` attribute.
`target` support this just fine.

So to be more clear, using an example from the doc, it seems impossible to do
the equivalent of `target("sse4.1,arch=core2")` using `target_clones`. Doing
`target_clones("sse4.1,arch=core2")` will create two functions instead of one.
(of course in reality what I might actually want is to make `target_clones` do
`target("sse4.1,arch=core2")` and target("default")).

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

* [Bug c/95777] Allow specifying more than one target options at the same time in target and target_clones attribute
  2020-06-20  5:02 [Bug c/95777] New: Allow specifying more than one target options at the same time in target and target_clones attribute yyc1992 at gmail dot com
  2020-06-22  7:41 ` [Bug c/95777] " rguenth at gcc dot gnu.org
  2020-06-22 13:33 ` yyc1992 at gmail dot com
@ 2020-06-22 14:19 ` yyc1992 at gmail dot com
  2020-06-23 19:38 ` marxin at gcc dot gnu.org
  2020-09-22 12:37 ` marxin at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: yyc1992 at gmail dot com @ 2020-06-22 14:19 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95777

--- Comment #3 from Yichao Yu <yyc1992 at gmail dot com> ---
And for backward compatibility maybe
`target_clones("(sse4.1,arch=core2),default")` would work?

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

* [Bug c/95777] Allow specifying more than one target options at the same time in target and target_clones attribute
  2020-06-20  5:02 [Bug c/95777] New: Allow specifying more than one target options at the same time in target and target_clones attribute yyc1992 at gmail dot com
                   ` (2 preceding siblings ...)
  2020-06-22 14:19 ` yyc1992 at gmail dot com
@ 2020-06-23 19:38 ` marxin at gcc dot gnu.org
  2020-09-22 12:37 ` marxin at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: marxin at gcc dot gnu.org @ 2020-06-23 19:38 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95777

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2020-06-23
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1
           Assignee|unassigned at gcc dot gnu.org      |marxin at gcc dot gnu.org

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

* [Bug c/95777] Allow specifying more than one target options at the same time in target and target_clones attribute
  2020-06-20  5:02 [Bug c/95777] New: Allow specifying more than one target options at the same time in target and target_clones attribute yyc1992 at gmail dot com
                   ` (3 preceding siblings ...)
  2020-06-23 19:38 ` marxin at gcc dot gnu.org
@ 2020-09-22 12:37 ` marxin at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: marxin at gcc dot gnu.org @ 2020-09-22 12:37 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95777

Martin Liška <marxin at gcc dot gnu.org> changed:

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

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
I don't see it as a high priority, thus leaving for now.

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

end of thread, other threads:[~2020-09-22 12:37 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-06-20  5:02 [Bug c/95777] New: Allow specifying more than one target options at the same time in target and target_clones attribute yyc1992 at gmail dot com
2020-06-22  7:41 ` [Bug c/95777] " rguenth at gcc dot gnu.org
2020-06-22 13:33 ` yyc1992 at gmail dot com
2020-06-22 14:19 ` yyc1992 at gmail dot com
2020-06-23 19:38 ` marxin at gcc dot gnu.org
2020-09-22 12:37 ` marxin at gcc dot gnu.org

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