* [committed][nvptx] Use --no-verify for sm_30
@ 2022-03-03 9:45 Tom de Vries
2022-03-31 7:40 ` [committed][nvptx] Fix ASM_SPEC workaround " Tom de Vries
0 siblings, 1 reply; 4+ messages in thread
From: Tom de Vries @ 2022-03-03 9:45 UTC (permalink / raw)
To: gcc-patches
Hi,
In PR97348, we ran into the problem that recent CUDA dropped support for
sm_30, which inhibited the build when building with CUDA bin in the path,
because the nvptx-tools assembler uses CUDA's ptxas to do ptx verification.
To fix this, in gcc-11 the default sm_xx was moved from sm_30 to sm_35.
This however broke support for sm_30 boards: an executable build for sm_30
might contain sm_35 code from the libraries, which are build with the default
sm_xx (PR104758).
We want to fix this by going back to having the libraries build with sm_30, as
was the case for gcc-5 to gcc-10. That however reintroduces the problem from
PR97348.
Deal with PR97348 in the simplest way possible: when calling the assembler for
sm_30, specify --no-verify.
This has the unfortunate effect that after fixing PR104758 by building
libraries with sm_30, the libraries are no longer verified. This can be
improved upon by:
- adding a configure test in gcc that tests if CUDA supports sm_30, and
if so disabling this patch
- dealing with this in nvptx-tools somehow, either:
- detect at ptxas execution time that it doesn't support sm_30, or
- detect this at nvptx-tool configure time.
Committed to trunk.
Thanks,
- Tom
[nvptx] Use --no-verify for sm_30
gcc/ChangeLog:
2022-03-03 Tom de Vries <tdevries@suse.de>
* config/nvptx/nvptx.h (ASM_SPEC): Add %{misa=sm_30:--no-verify}.
---
gcc/config/nvptx/nvptx.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/config/nvptx/nvptx.h b/gcc/config/nvptx/nvptx.h
index 4ab412bc7d8..3ca22a595d2 100644
--- a/gcc/config/nvptx/nvptx.h
+++ b/gcc/config/nvptx/nvptx.h
@@ -32,7 +32,7 @@
/* Default needs to be in sync with default for misa in nvptx.opt.
We add a default here to work around a hard-coded sm_30 default in
nvptx-as. */
-#define ASM_SPEC "%{misa=*:-m %*; :-m sm_35}"
+#define ASM_SPEC "%{misa=*:-m %*; :-m sm_35}%{misa=sm_30:--no-verify}"
#define TARGET_CPU_CPP_BUILTINS() nvptx_cpu_cpp_builtins ()
^ permalink raw reply [flat|nested] 4+ messages in thread
* [committed][nvptx] Fix ASM_SPEC workaround for sm_30
@ 2022-03-31 7:40 ` Tom de Vries
2022-04-07 14:17 ` Thomas Schwinge
0 siblings, 1 reply; 4+ messages in thread
From: Tom de Vries @ 2022-03-31 7:40 UTC (permalink / raw)
To: gcc-patches
Hi,
Newer versions of CUDA no longer support sm_30, and nvptx-tools as
currently doesn't handle that gracefully when verifying
( https://github.com/MentorEmbedded/nvptx-tools/issues/30 ).
There's a --no-verify work-around in place in ASM_SPEC, but that one doesn't
work when using -Wa,--verify on the command line.
Use a more robust workaround: verify using sm_35 when misa=sm_30 is specified
(either implicitly or explicitly).
Tested on nvptx.
Committed to trunk.
Thanks,
- Tom
[nvptx] Fix ASM_SPEC workaround for sm_30
gcc/ChangeLog:
2022-03-30 Tom de Vries <tdevries@suse.de>
* config/nvptx/nvptx.h (ASM_SPEC): Use "-m sm_35" for -misa=sm_30.
---
gcc/config/nvptx/nvptx.h | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/gcc/config/nvptx/nvptx.h b/gcc/config/nvptx/nvptx.h
index 75ac7a666b1..3b06f33032f 100644
--- a/gcc/config/nvptx/nvptx.h
+++ b/gcc/config/nvptx/nvptx.h
@@ -29,10 +29,24 @@
#define STARTFILE_SPEC "%{mmainkernel:crt0.o}"
-/* Default needs to be in sync with default for misa in nvptx.opt.
- We add a default here to work around a hard-coded sm_30 default in
- nvptx-as. */
-#define ASM_SPEC "%{misa=*:-m %*; :-m sm_35}%{misa=sm_30:--no-verify}"
+/* Newer versions of CUDA no longer support sm_30, and nvptx-tools as
+ currently doesn't handle that gracefully when verifying
+ ( https://github.com/MentorEmbedded/nvptx-tools/issues/30 ). Work around
+ this by verifying with sm_35 when having misa=sm_30 (either implicitly
+ or explicitly). */
+#define ASM_SPEC \
+ "%{" \
+ /* Explict misa=sm_30. */ \
+ "misa=sm_30:-m sm_35" \
+ /* Separator. */ \
+ "; " \
+ /* Catch-all. */ \
+ "misa=*:-m %*" \
+ /* Separator. */ \
+ "; " \
+ /* Implicit misa=sm_30. */ \
+ ":-m sm_35" \
+ "}"
#define TARGET_CPU_CPP_BUILTINS() nvptx_cpu_cpp_builtins ()
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [committed][nvptx] Fix ASM_SPEC workaround for sm_30
2022-03-31 7:40 ` [committed][nvptx] Fix ASM_SPEC workaround " Tom de Vries
@ 2022-04-07 14:17 ` Thomas Schwinge
2022-04-11 9:10 ` Tom de Vries
0 siblings, 1 reply; 4+ messages in thread
From: Thomas Schwinge @ 2022-04-07 14:17 UTC (permalink / raw)
To: Tom de Vries, gcc-patches
Hi!
On 2022-03-31T09:40:47+0200, Tom de Vries via Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
> Newer versions of CUDA no longer support sm_30, and nvptx-tools as
> currently doesn't handle that gracefully when verifying
> ( https://github.com/MentorEmbedded/nvptx-tools/issues/30 ).
There's now <https://github.com/MentorEmbedded/nvptx-tools/pull/33>
'as: Deal with CUDA 11.0, "Support for Kepler 'sm_30' and 'sm_32'
architecture based products is dropped"' available for comment/testing.
> There's a --no-verify work-around in place in ASM_SPEC, but that one doesn't
> work when using -Wa,--verify on the command line.
With that resolved in nvptx-tools, we may then revert these GCC-level
workarounds, GCC commit bf4832d6fa817f66009f100a9cd68953062add7d
"[nvptx] Fix ASM_SPEC workaround for sm_30", and
GCC commit 12fa7641ceed9c9139e2ea7b62c11f3dc5b6f6f4
"[nvptx] Use --no-verify for sm_30". OK to push, once nvptx-tools ready?
> Use a more robust workaround: verify using sm_35 when misa=sm_30 is specified
> (either implicitly or explicitly).
Thanks for that suggestion!
Grüße
Thomas
-----------------
Siemens Electronic Design Automation GmbH; Anschrift: Arnulfstraße 201, 80634 München; Gesellschaft mit beschränkter Haftung; Geschäftsführer: Thomas Heurung, Frank Thürauf; Sitz der Gesellschaft: München; Registergericht München, HRB 106955
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [committed][nvptx] Fix ASM_SPEC workaround for sm_30
2022-04-07 14:17 ` Thomas Schwinge
@ 2022-04-11 9:10 ` Tom de Vries
0 siblings, 0 replies; 4+ messages in thread
From: Tom de Vries @ 2022-04-11 9:10 UTC (permalink / raw)
To: Thomas Schwinge, gcc-patches
On 4/7/22 16:17, Thomas Schwinge wrote:
> Hi!
>
> On 2022-03-31T09:40:47+0200, Tom de Vries via Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
>> Newer versions of CUDA no longer support sm_30, and nvptx-tools as
>> currently doesn't handle that gracefully when verifying
>> ( https://github.com/MentorEmbedded/nvptx-tools/issues/30 ).
>
> There's now <https://github.com/MentorEmbedded/nvptx-tools/pull/33>
> 'as: Deal with CUDA 11.0, "Support for Kepler 'sm_30' and 'sm_32'
> architecture based products is dropped"' available for comment/testing.
>
>> There's a --no-verify work-around in place in ASM_SPEC, but that one doesn't
>> work when using -Wa,--verify on the command line.
>
> With that resolved in nvptx-tools, we may then revert these GCC-level
> workarounds, GCC commit bf4832d6fa817f66009f100a9cd68953062add7d
> "[nvptx] Fix ASM_SPEC workaround for sm_30", and
> GCC commit 12fa7641ceed9c9139e2ea7b62c11f3dc5b6f6f4
> "[nvptx] Use --no-verify for sm_30". OK to push, once nvptx-tools ready?
>
>> Use a more robust workaround: verify using sm_35 when misa=sm_30 is specified
>> (either implicitly or explicitly).
>
> Thanks for that suggestion!
>
Hi,
I've tested the nvptx-tools patch in combination with a patch that
remote ASM_SPEC, and that went fine.
[ Well apart from a new libgomp FAIL:
...
FAIL: libgomp.oacc-fortran/private-variables.f90
-DACC_DEVICE_TYPE_nvidia=1 -DACC_MEM_SHARED=0 -foffload=nvptx-none -O1
at line 142 (test for bogus messages, line 131)
...
but I assume that's unrelated ]
So, patch that removes ASM_SPEC pre-approved.
Thanks,
- Tom
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2022-04-11 9:10 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-03-03 9:45 [committed][nvptx] Use --no-verify for sm_30 Tom de Vries
2022-03-31 7:40 ` [committed][nvptx] Fix ASM_SPEC workaround " Tom de Vries
2022-04-07 14:17 ` Thomas Schwinge
2022-04-11 9:10 ` Tom de Vries
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).