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* [Bug target/106279] New: reload problem on arm iwmmxt
@ 2022-07-13  8:01 dcb314 at hotmail dot com
  2022-07-13  9:10 ` [Bug target/106279] " wilco at gcc dot gnu.org
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: dcb314 at hotmail dot com @ 2022-07-13  8:01 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106279

            Bug ID: 106279
           Summary: reload problem on arm iwmmxt
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

For the C testsuite file ./gcc.target/aarch64/vect_unary_1.c, compiled
by an ARM cross compiler, with target arch set to iwmmxt, does this:

$ /home/dcb/raspberrypi/results/bin/arm-linux-gnueabihf-gcc -c -march=iwmmxt 
bug827.c
during RTL pass: reload
./gcc.target/aarch64/vect_unary_1.c: In function ‘test2_int_clz_int’:
./gcc.target/aarch64/vect_unary_1.c:15:1: internal compiler error: maximum
number of generated reload insns per insn achieved (90)
   15 | }                                                                      
\
      | ^
./gcc.target/aarch64/vect_unary_1.c:161:1: note: in expansion of macro ‘TEST2’
  161 | TEST2 (int, clz, int)
      | ^~~~~
0xe06010 lra_constraints(bool)
    /home/dcb/gcc/trunk.git/gcc/lra-constraints.cc:5126

Similar things happen with target arch set to iwmmxt2.

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

* [Bug target/106279] reload problem on arm iwmmxt
  2022-07-13  8:01 [Bug target/106279] New: reload problem on arm iwmmxt dcb314 at hotmail dot com
@ 2022-07-13  9:10 ` wilco at gcc dot gnu.org
  2022-07-13  9:15 ` dcb314 at hotmail dot com
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: wilco at gcc dot gnu.org @ 2022-07-13  9:10 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106279

Wilco <wilco at gcc dot gnu.org> changed:

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

--- Comment #1 from Wilco <wilco at gcc dot gnu.org> ---
iwmmxt has been dead for 2 decades now - it's support has most likely
bitrotted, so I'm surprised anyone is trying to use it...

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

* [Bug target/106279] reload problem on arm iwmmxt
  2022-07-13  8:01 [Bug target/106279] New: reload problem on arm iwmmxt dcb314 at hotmail dot com
  2022-07-13  9:10 ` [Bug target/106279] " wilco at gcc dot gnu.org
@ 2022-07-13  9:15 ` dcb314 at hotmail dot com
  2022-07-13  9:17 ` wilco at gcc dot gnu.org
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: dcb314 at hotmail dot com @ 2022-07-13  9:15 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106279

--- Comment #2 from David Binderman <dcb314 at hotmail dot com> ---
(In reply to Wilco from comment #1)
> iwmmxt has been dead for 2 decades now - it's support has most likely
> bitrotted, so I'm surprised anyone is trying to use it...

Time to remove support for it, or just mark this bug report as WONTFIX ?

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

* [Bug target/106279] reload problem on arm iwmmxt
  2022-07-13  8:01 [Bug target/106279] New: reload problem on arm iwmmxt dcb314 at hotmail dot com
  2022-07-13  9:10 ` [Bug target/106279] " wilco at gcc dot gnu.org
  2022-07-13  9:15 ` dcb314 at hotmail dot com
@ 2022-07-13  9:17 ` wilco at gcc dot gnu.org
  2022-09-01 13:01 ` rearnsha at gcc dot gnu.org
  2022-09-01 13:06 ` rearnsha at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: wilco at gcc dot gnu.org @ 2022-07-13  9:17 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106279

--- Comment #3 from Wilco <wilco at gcc dot gnu.org> ---
(In reply to David Binderman from comment #2)
> (In reply to Wilco from comment #1)
> > iwmmxt has been dead for 2 decades now - it's support has most likely
> > bitrotted, so I'm surprised anyone is trying to use it...
> 
> Time to remove support for it, or just mark this bug report as WONTFIX ?

Both!

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

* [Bug target/106279] reload problem on arm iwmmxt
  2022-07-13  8:01 [Bug target/106279] New: reload problem on arm iwmmxt dcb314 at hotmail dot com
                   ` (2 preceding siblings ...)
  2022-07-13  9:17 ` wilco at gcc dot gnu.org
@ 2022-09-01 13:01 ` rearnsha at gcc dot gnu.org
  2022-09-01 13:06 ` rearnsha at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: rearnsha at gcc dot gnu.org @ 2022-09-01 13:01 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106279

Richard Earnshaw <rearnsha at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2022-09-01
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #4 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
In a general cross compiler you need: -march=iwmmxt -mfpu=vfp -mfloat-abi=hard
to reproduce.

This seems to need a combination of VFP, iWMMX and the hard-float ABI.  I don't
think we've ever claimed to support this.  Whilst there may be a few devices
with both iWMMX and VFP present, I think that's mostly for backwards
compatibility.

So I think we should resolve this as WONTFIX, but it would be nice if the
compiler could reject this upfront rather than ICEing later on.

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

* [Bug target/106279] reload problem on arm iwmmxt
  2022-07-13  8:01 [Bug target/106279] New: reload problem on arm iwmmxt dcb314 at hotmail dot com
                   ` (3 preceding siblings ...)
  2022-09-01 13:01 ` rearnsha at gcc dot gnu.org
@ 2022-09-01 13:06 ` rearnsha at gcc dot gnu.org
  4 siblings, 0 replies; 6+ messages in thread
From: rearnsha at gcc dot gnu.org @ 2022-09-01 13:06 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106279

--- Comment #5 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
Technical note: the compiler is missing pattern alternatives to move iwmmxt
register values to VFP registers.  There's no way to do this directly, so we'd
need to allow copying via core registers.

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

end of thread, other threads:[~2022-09-01 13:06 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-13  8:01 [Bug target/106279] New: reload problem on arm iwmmxt dcb314 at hotmail dot com
2022-07-13  9:10 ` [Bug target/106279] " wilco at gcc dot gnu.org
2022-07-13  9:15 ` dcb314 at hotmail dot com
2022-07-13  9:17 ` wilco at gcc dot gnu.org
2022-09-01 13:01 ` rearnsha at gcc dot gnu.org
2022-09-01 13:06 ` rearnsha at gcc dot gnu.org

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