On Tue, 20 Feb 2024, Thomas Schwinge wrote:
> Hi Richard!
>
> On 2024-02-20T08:44:35+0100, Richard Biener <rguent...@suse.de> wrote:
> > On Mon, 19 Feb 2024, Thomas Schwinge wrote:
> >> On 2024-02-19T17:31:20+0100, I wrote:
> >> > On 2024-02-19T11:52:55+0100, Richard Biener <rguent...@suse.de> wrote:
> >> >> On Mon, 19 Feb 2024, Thomas Schwinge wrote:
> >> >>> On 2024-02-16T14:53:04+0100, I wrote:
> >> >>> > On 2024-02-16T12:41:06+0000, Andrew Stubbs <a...@baylibre.com> wrote:
> >> >>> >> On 16/02/2024 12:26, Richard Biener wrote:
> >> >>> >>> On Fri, 16 Feb 2024, Andrew Stubbs wrote:
> >> >>> >>>> On 16/02/2024 10:17, Richard Biener wrote:
> >> >>> >>>>> On Fri, 16 Feb 2024, Thomas Schwinge wrote:
> >> >>> >>>>>> On 2023-10-20T12:51:03+0100, Andrew Stubbs
> >> >>> >>>>>> <a...@codesourcery.com> wrote:
> >> >>> >>>>>>> I've committed this patch
> >> >>> >>>>>>
> >> >>> >>>>>> ... as commit c7ec7bd1c6590cf4eed267feab490288e0b8d691
> >> >>> >>>>>> "amdgcn: add -march=gfx1030 EXPERIMENTAL", which the later
> >> >>> >>>>>> RDNA3/gfx1100
> >> >>> >>>>>> support builds on top of, and that's what I'm currently working
> >> >>> >>>>>> on
> >> >>> >>>>>> getting proper GCC/GCN target (not offloading) results for.
> >> >>> >>>>>>
> >> >>> >>>>>> Now looking at 'gcc.dg/vect/bb-slp-cond-1.c', which is
> >> >>> >>>>>> reasonably simple,
> >> >>> >>>>>> and hopefully representative for other SLP execution test FAILs
> >> >>> >>>>>> (regressions compared to my earlier non-gfx1100 testing).
> >> >>> >>>>>>
> >> >>> >>>>>> $ build-gcc/gcc/xgcc -Bbuild-gcc/gcc/
> >> >>> >>>>>> source-gcc/gcc/testsuite/gcc.dg/vect/bb-slp-cond-1.c
> >> >>> >>>>>> --sysroot=install/amdgcn-amdhsa -ftree-vectorize
> >> >>> >>>>>> -fno-tree-loop-distribute-patterns -fno-vect-cost-model
> >> >>> >>>>>> -fno-common
> >> >>> >>>>>> -O2 -fdump-tree-slp-details -fdump-tree-vect-details
> >> >>> >>>>>> -isystem
> >> >>> >>>>>> build-gcc/amdgcn-amdhsa/gfx1100/newlib/targ-include
> >> >>> >>>>>> -isystem
> >> >>> >>>>>> source-gcc/newlib/libc/include
> >> >>> >>>>>> -Bbuild-gcc/amdgcn-amdhsa/gfx1100/newlib/
> >> >>> >>>>>> -Lbuild-gcc/amdgcn-amdhsa/gfx1100/newlib -wrapper
> >> >>> >>>>>> setarch,--addr-no-randomize -fdump-tree-all-all
> >> >>> >>>>>> -fdump-ipa-all-all
> >> >>> >>>>>> -fdump-rtl-all-all -save-temps -march=gfx1100
> >> >>> >>>>>>
> >> >>> >>>>>> The '-march=gfx1030' 'a-bb-slp-cond-1.s' is identical (apart
> >> >>> >>>>>> from
> >> >>> >>>>>> 'TARGET_PACKED_WORK_ITEMS' in
> >> >>> >>>>>> 'gcn_target_asm_function_prologue'), so I
> >> >>> >>>>>> suppose will also exhibit the same failure mode, once again?
> >> >>> >>>>>>
> >> >>> >>>>>> Compared to '-march=gfx90a', the differences begin in
> >> >>> >>>>>> 'a-bb-slp-cond-1.c.266r.expand' (only!), down to
> >> >>> >>>>>> 'a-bb-slp-cond-1.s'.
> >> >>> >>>>>>
> >> >>> >>>>>> Changed like:
> >> >>> >>>>>>
> >> >>> >>>>>> @@ -38,10 +38,10 @@ int main ()
> >> >>> >>>>>> #pragma GCC novector
> >> >>> >>>>>> for (i = 1; i < N; i++)
> >> >>> >>>>>> if (a[i] != i%4 + 1)
> >> >>> >>>>>> - abort ();
> >> >>> >>>>>> + __builtin_printf("%d %d != %d\n", i, a[i], i%4 +
> >> >>> >>>>>> 1);
> >> >>> >>>>>>
> >> >>> >>>>>> if (a[0] != 5)
> >> >>> >>>>>> - abort ();
> >> >>> >>>>>> + __builtin_printf("%d %d != %d\n", 0, a[0], 5);
> >> >>> >>>>>>
> >> >>> >>>>>> ..., we see:
> >> >>> >>>>>>
> >> >>> >>>>>> $ flock /tmp/gcn.lock build-gcc/gcc/gcn-run a.out
> >> >>> >>>>>> 40 5 != 1
> >> >>> >>>>>> 41 6 != 2
> >> >>> >>>>>> 42 7 != 3
> >> >>> >>>>>> 43 8 != 4
> >> >>> >>>>>> 44 5 != 1
> >> >>> >>>>>> 45 6 != 2
> >> >>> >>>>>> 46 7 != 3
> >> >>> >>>>>> 47 8 != 4
> >> >>> >>>>>>
> >> >>> >>>>>> '40..47' are the 'i = 10..11' in 'foo', and the expectation is
> >> >>> >>>>>> 'a[i * stride + 0..3] != 0'. So, either some earlier iteration
> >> >>> >>>>>> has
> >> >>> >>>>>> scribbled zero values over these (vector lane masking issue,
> >> >>> >>>>>> perhaps?),
> >> >>> >>>>>> or some other code generation issue?
> >> >>> >
> >> >>> >>>> [...], I must be doing something different because
> >> >>> >>>> vect/bb-slp-cond-1.c
> >> >>> >>>> passes for me, on gfx1100.
> >> >>> >
> >> >>> > That's strange. I've looked at your log file (looks good), and used
> >> >>> > your
> >> >>> > toolchain to compile, and your 'gcn-run' to invoke, and still do get:
> >> >>> >
> >> >>> > $ flock /tmp/gcn.lock ~/gcn-run ~/bb-slp-cond-1.exe
> >> >>> > GCN Kernel Aborted
> >> >>> > Kernel aborted
> >> >>> >
> >> >>> > Andrew, later on, please try what happens when you put an
> >> >>> > unconditional
> >> >>> > 'abort' call into a test case?
> >> >>>
> >> >>> Andrew, any luck with that yet?
> >> >>>
> >> >>> Richard, are you able to reproduce the 'gcc.dg/vect/bb-slp-cond-1.c'
> >> >>> execution test failure mentioned above (manual compilation and
> >> >>> 'gcn-run')?
> >> >>
> >> >> No, when manually compiling/running the testcase it works fine for me.
> >> >
> >> > I've updated my GCC master branch sources, but it still fails for me:
> >> >
> >> > $ build-gcc/gcc/xgcc -Bbuild-gcc/gcc/
> >> > source-gcc/gcc/testsuite/gcc.dg/vect/bb-slp-cond-1.c
> >> > --sysroot=install/amdgcn-amdhsa -isystem
> >> > build-gcc/amdgcn-amdhsa/gfx1100/newlib/targ-include -isystem
> >> > source-gcc/newlib/libc/include -Bbuild-gcc/amdgcn-amdhsa/gfx1100/newlib/
> >> > -Lbuild-gcc/amdgcn-amdhsa/gfx1100/newlib -march=gfx1100 -ftree-vectorize
> >> > -fno-tree-loop-distribute-patterns -fno-vect-cost-model -fno-common -O2
> >> > -save-temps
> >> > $ flock /tmp/gcn.lock build-gcc/gcc/gcn-run a.out
> >> > GCN Kernel Aborted
> >> > Kernel aborted
> >> >
> >> > Strange.
> >> >
> >> > In 'bb-slp-cond-1.tar.xz' I'm attaching the files I've built. Could you
> >> > please compare those to yours and try 'gcn-run gfx1030/a.out'?
> >>
> >> Actually: 'gcn-run gfx1030/a.out' a few times -- our dear friend
> >> Nondeterminism seems to be at play here... :-|
> >
> > What's your set of compile options? I don't manage to get close
> > to your gfx1030 assembly when using your preprocessed source ...
> >
> > I've tried -march=gfx1030 -O[23] [-fno-vect-cost-model]
>
> See the 'xgcc' command line just a few lines above? ;-)
>
> -ftree-vectorize -fno-tree-loop-distribute-patterns -fno-vect-cost-model
> -fno-common -O2
>
> That's what I originally found in 'gcc.log'.
OK, with that I can reproduce the issue. -O2 -ftree-vectorize seems
to be enough to trigger it. It's indeed somewhat random whether it
fails or not ...
Richard.
>
> Gr??e
> Thomas
>
>
> > Looks like you use -fno-omit-frame-pointer but then I still see
> > -mine +yours
> >
> > - v_readlane_b32 s18, v4, 0
> > - v_readlane_b32 s19, v5, 0
> > - s_add_u32 s18, s18, s26
> > - s_addc_u32 s19, s19, s27
> > - v_writelane_b32 v4, s18, 0
> > - v_writelane_b32 v5, s19, 0
> > - s_mov_b32 s18, s14
> > - s_mov_b32 s19, s15
> > - s_mov_b32 s22, scc
> > - s_add_u32 s18, s18, 4096
> > - s_addc_u32 s19, s19, 0
> > - s_cmpk_lg_u32 s22, 0
> > - v_writelane_b32 v6, s18, 0
> > - v_writelane_b32 v7, s19, 0
> > - flat_store_dwordx2 v[6:7], v[4:5]
> > + v_writelane_b32 v6, s26, 0
> > + v_writelane_b32 v7, s27, 0
> > + v_add_co_u32 v4, vcc, v6, v4
> > + v_add_co_ci_u32 v5, vcc, v7, v5, vcc
> >
> > and more changes.
> >
> > Richard.
> >
> >>
> >> Gr??e
> >> Thomas
> >>
> >>
> >> >> Didn't yet get to try the .exp files
> >> >>
> >> >> Richard.
> >> >>
> >> >>>
> >> >>> Gr??e
> >> >>> Thomas
> >> >>>
> >> >>>
> >> >>> >>> I didn't try to run it - when doing make check-gcc fails to using
> >> >>> >>> gcn-run for test invocation
> >> >>> >
> >> >>> > Note, that for such individual test cases, invoking the compiler and
> >> >>> > then
> >> >>> > 'gcn-run' manually would seem easiest?
> >> >>> >
> >> >>> >>> what's the trick to make it do that?
> >> >>> >
> >> >>> > I tell you've probably not done much "embedded" or simulator testing
> >> >>> > of
> >> >>> > GCC targets? ;-P
> >> >>> >
> >> >>> >> There's a config file for nvptx here:
> >> >>> >> https://github.com/SourceryTools/nvptx-tools/blob/master/nvptx-none-run.exp
> >> >>> >
> >> >>> > Yes, and I have pending some updates to that one, to be finished once
> >> >>> > I've generally got my testing set up again, to a sufficient degree...
> >> >>> >
> >> >>> >> You can probably make the obvious adjustments. I think Thomas has a
> >> >>> >> GCN
> >> >>> >> version with a few more features.
> >> >>> >
> >> >>> > Right. I'm attaching my current 'amdgcn-amdhsa-run.exp'.
> >> >>> >
> >> >>> > I'm aware that the 'set_board_info gcc,[...] [...]' may be
> >> >>> > obsolete/wrong
> >> >>> > (as Andrew also noted privately) -- likewise, at least in part, for
> >> >>> > GCC/nvptx, which is where I copied all that from. (Will revise
> >> >>> > later;
> >> >>> > not relevant for this discussion, here.)
> >> >>> >
> >> >>> > Similar to what I've recently added to libgomp, there is 'flock'ing
> >> >>> > here,
> >> >>> > so that you may use 'make -j[...] check' for (partial) parallelism,
> >> >>> > but
> >> >>> > still all execution testing runs serialized. I found this to greatly
> >> >>> > help denoise the test results. (Not ideal, of course, but improving
> >> >>> > that
> >> >>> > is for later, too.)
> >> >>> >
> >> >>> > You may want to disable the 'HSA_STATUS_ERROR_OUT_OF_RESOURCES'
> >> >>> > thing if
> >> >>> > that doesn't work like that in your case. (I've no idea what
> >> >>> > 'amdgpu_gpu_recover' would do if the GPU is also used for display.)
> >> >>> > But
> >> >>> > this, again, greatly helps denoise test results, at least for the one
> >> >>> > system I'm currently testing on.
> >> >>> >
> >> >>> > I intend to publish proper documentation of all this, later on --
> >> >>> > happy
> >> >>> > to answer any questions in the mean time.
> >> >>> >
> >> >>> > If you don't already have a common directory for DejaGnu board
> >> >>> > files, put
> >> >>> > 'amdgcn-amdhsa-run.exp' into '~/tmp/amdgcn-amdhsa/', for example,
> >> >>> > and add
> >> >>> > a 'dejagnu.exp' file next to it:
> >> >>> >
> >> >>> > lappend boards_dir ~/tmp/amdgcn-amdhsa
> >> >>> >
> >> >>> > Prepare:
> >> >>> >
> >> >>> > $ DEJAGNU=$HOME/tmp/amdgcn-amdhsa/dejagnu.exp
> >> >>> > $ export DEJAGNU
> >> >>> > $ AMDGCN_AMDHSA_RUN=[...]/build-gcc/gcc/gcn-run
> >> >>> > $ export AMDGCN_AMDHSA_RUN
> >> >>> > $ # If necessary:
> >> >>> > $ AMDGCN_AMDHSA_LD_LIBRARY_PATH=/opt/rocm/lib
> >> >>> > $
> >> >>> > LD_LIBRARY_PATH=$AMDGCN_AMDHSA_LD_LIBRARY_PATH${LD_LIBRARY_PATH+:$LD_LIBRARY_PATH}
> >> >>> > $ export LD_LIBRARY_PATH
> >> >>> >
> >> >>> > ..., and then run:
> >> >>> >
> >> >>> > $ make -j8 check-gcc-c
> >> >>> > RUNTESTFLAGS='--target_board=amdgcn-amdhsa-run/-march=gfx1030
> >> >>> > vect.exp'
> >> >>> >
> >> >>> > Oh, and I saw that on <https://gcc.gnu.org/wiki/Offloading>, Tobias
> >> >>> > has
> >> >>> > recently put into a new "Using the GPU as stand-alone system" section
> >> >>> > some similar information. (..., but this should, in my opinion, be
> >> >>> > on a
> >> >>> > different page, as it's explicitly *not* about what we understand as
> >> >>> > offloading.)
> >> >>> >
> >> >>> >> I usually use the CodeSourcery magic stack of scripts for testing
> >> >>> >> installed toolchains on remote devices, so I'm not too familiar
> >> >>> >> with
> >> >>> >> using Dejagnu directly.
> >> >>> >
> >> >>> > Tsk... ;'-|
> >> >>> >
> >> >>> >
> >> >>> > Gr??e
> >> >>> > Thomas
> >> >>>
> >> >>
> >> >> --
> >> >> Richard Biener <rguent...@suse.de>
> >> >> SUSE Software Solutions Germany GmbH,
> >> >> Frankenstrasse 146, 90461 Nuernberg, Germany;
> >> >> GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG
> >> >> Nuernberg)
> >>
> >
> > --
> > Richard Biener <rguent...@suse.de>
> > SUSE Software Solutions Germany GmbH,
> > Frankenstrasse 146, 90461 Nuernberg, Germany;
> > GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
