Re: [committed] nvptx, libgfortran: Switch out of "minimal" mode
Sandra Loosemore wrote:
On 6/6/24 06:06, Tobias Burnus wrote:
+@item I/O within OpenMP target regions and OpenACC compute regions
is supported
+ using the C library @code{printf} functions.
+ Additionally, the Fortran @code{print}/@code{write}
statements are
+ supported within OpenMP target regions, but not yet OpenACC
compute
+ regions. @c The latter needs
'GOMP_NVPTX_NATIVE_GPU_THREAD_STACK_SIZE'.
I think an "in" (or 'within') is missing before OpenACC.
Yes, "...not yet within OpenACC compute regions", please.
Thanks! Committed as https://gcc.gnu.org/r15-1072-g423522aacd9f30
Tobias
Re: [committed] nvptx, libgfortran: Switch out of "minimal" mode
On 6/6/24 06:06, Tobias Burnus wrote:
Hi Thomas,
regarding the commit r15-1070-g3a4775d4403f2e /
https://gcc.gnu.org/r15-1070
First, thanks for adding I/O support to nvptx offloading.
I have a wording nit, to be confirmed by a native speaker:
--- a/libgomp/libgomp.texi
+++ b/libgomp/libgomp.texi
...
+@item I/O within OpenMP target regions and OpenACC compute regions is
supported
+ using the C library @code{printf} functions.
+ Additionally, the Fortran @code{print}/@code{write} statements are
+ supported within OpenMP target regions, but not yet OpenACC
compute
+ regions. @c The latter needs
'GOMP_NVPTX_NATIVE_GPU_THREAD_STACK_SIZE'.
I think an "in" (or 'within') is missing before OpenACC.
Yes, "...not yet within OpenACC compute regions", please.
-Sandra
nvptx, libgfortran: Switch out of "minimal" mode
Hi!
On 2023-01-20T22:16:00+0100, Hi wrote:
> On 2023-01-20T22:04:02+0100, I wrote:
>> We've been (t)asked to enable (portions of) GCC/Fortran I/O for nvptx
>> offloading, which means building a normal (non-'LIBGFOR_MINIMAL')
>> configuration of libgfortran.
>
> This is achieved by 'nvptx, libgfortran: Switch out of "minimal" mode',
> see attached, again based on WIP work by Andrew Stubbs.
I've recently slightly revised this, in particular:
> The OpenACC XFAILs: "[...] overflows the stack [...]"
... I now avoid by use of commit 0d25989d60d15866ef4737d66e02432f50717255
"nvptx offloading: 'GOMP_NVPTX_NATIVE_GPU_THREAD_STACK_SIZE' environment
variable [PR97384, PR105274]".
The underlying issue remains...
> [...] unresolved at this point; see the discussion around
> "Handling of large stack objects in GPU code generation -- maybe transform
> into heap allocation?",
> and my "nvptx: '-mframe-malloc-threshold', '-Wframe-malloc-threshold'"
> experimenting. (The latter works to some extent, but also has other
> issues that I shall detail at some later point in time.)
(No progress.)
Pushed to trunk branch commit 3a4775d4403f2e88b589e88a9937cc1fd45a0e87
'nvptx, libgfortran: Switch out of "minimal" mode', see attached.
This, unsurprisingly, also greatly improves GCC/Fortran test results for
nvptx target.
Grüße
Thomas
>From 3a4775d4403f2e88b589e88a9937cc1fd45a0e87 Mon Sep 17 00:00:00 2001
From: Thomas Schwinge
Date: Wed, 5 Jun 2024 13:13:24 +0200
Subject: [PATCH] nvptx, libgfortran: Switch out of "minimal" mode
..., in order to enable (portions of) Fortran I/O, for example.
libgfortran/
* configure.ac: No longer set 'LIBGFOR_MINIMAL' for nvptx.
* configure: Regenerate.
libgomp/
* libgomp.texi (nvptx): Update.
* testsuite/libgomp.fortran/target-print-1-nvptx.f90: Remove.
* testsuite/libgomp.fortran/target-print-1.f90: Adjust.
* testsuite/libgomp.oacc-fortran/error_stop-2-nvptx.f: New.
* testsuite/libgomp.oacc-fortran/error_stop-2.f: Adjust.
* testsuite/libgomp.oacc-fortran/print-1-nvptx.f90: Adjust.
* testsuite/libgomp.oacc-fortran/print-1.f90: Adjust.
* testsuite/libgomp.oacc-fortran/stop-2-nvptx.f: New.
* testsuite/libgomp.oacc-fortran/stop-2.f: Adjust.
Co-authored-by: Andrew Stubbs
---
libgfortran/configure | 21 --
libgfortran/configure.ac | 17 +++-
libgomp/libgomp.texi | 10 +++--
.../libgomp.fortran/target-print-1-nvptx.f90 | 11 -
.../libgomp.fortran/target-print-1.f90| 3 --
.../libgomp.oacc-fortran/error_stop-2-nvptx.f | 39 ++
.../libgomp.oacc-fortran/error_stop-2.f | 3 +-
.../libgomp.oacc-fortran/print-1-nvptx.f90| 40 +++
.../libgomp.oacc-fortran/print-1.f90 | 4 +-
.../libgomp.oacc-fortran/stop-2-nvptx.f | 36 +
.../testsuite/libgomp.oacc-fortran/stop-2.f | 3 +-
11 files changed, 134 insertions(+), 53 deletions(-)
delete mode 100644 libgomp/testsuite/libgomp.fortran/target-print-1-nvptx.f90
create mode 100644 libgomp/testsuite/libgomp.oacc-fortran/error_stop-2-nvptx.f
create mode 100644 libgomp/testsuite/libgomp.oacc-fortran/stop-2-nvptx.f
diff --git a/libgfortran/configure b/libgfortran/configure
index 774dd52fc95..11a1bc5f070 100755
--- a/libgfortran/configure
+++ b/libgfortran/configure
@@ -6207,17 +6207,12 @@ else
fi
-# For GPU offloading, not everything in libfortran can be supported.
-# Currently, the only target that has this problem is nvptx. The
-# following is a (partial) list of features that are unsupportable on
-# this particular target:
-# * Constructors
-# * alloca
-# * C library support for I/O, with printf as the one notable exception
-# * C library support for other features such as signal, environment
-# variables, time functions
-
- if test "x${target_cpu}" = xnvptx; then
+# "Minimal" mode is for targets that cannot (yet) support all features of
+# libgfortran. It avoids the need for working constructors, alloca, and C
+# library support for I/O, signals, environment variables, time functions, etc.
+# At present there are no targets that require this mode.
+
+ if false; then
LIBGFOR_MINIMAL_TRUE=
LIBGFOR_MINIMAL_FALSE='#'
else
@@ -12852,7 +12847,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 12855 "configure"
+#line 12850 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
@@ -12958,7 +12953,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 12961 "configure"
+#line 12956 "configure"
Re: [committed] nvptx, libgfortran: Switch out of "minimal" mode
Hi Thomas,
regarding the commit r15-1070-g3a4775d4403f2e / https://gcc.gnu.org/r15-1070
First, thanks for adding I/O support to nvptx offloading.
I have a wording nit, to be confirmed by a native speaker:
--- a/libgomp/libgomp.texi
+++ b/libgomp/libgomp.texi
...
+@item I/O within OpenMP target regions and OpenACC compute regions is
supported
+ using the C library @code{printf} functions.
+ Additionally, the Fortran @code{print}/@code{write} statements are
+ supported within OpenMP target regions, but not yet OpenACC compute
+ regions. @c The latter needs
'GOMP_NVPTX_NATIVE_GPU_THREAD_STACK_SIZE'.
I think an "in" (or 'within') is missing before OpenACC.
Otherwise, it seemed to fine at a glance – and I am happy that that
feature now finally works :-)
Hooray, no longer using reverse offload ("!$omp target
device(ancestor:1)") for Fortran I/O when debugging.
Thanks,
Tobias
Update 'libgomp/libgomp.texi' for 'nvptx, libgfortran: Switch out of "minimal" mode' (was: nvptx, libgfortran: Switch out of "minimal" mode)
Hi!
On 2023-01-20T22:16:00+0100, I wrote:
> On 2023-01-20T22:04:02+0100, I wrote:
>> We've been (t)asked to enable (portions of) GCC/Fortran I/O for nvptx
>> offloading, which means building a normal (non-'LIBGFOR_MINIMAL')
>> configuration of libgfortran.
>
> This is achieved by 'nvptx, libgfortran: Switch out of "minimal" mode',
> see attached, again based on WIP work by Andrew Stubbs. This I've just
> pushed to devel/omp/gcc-12 branch in
> commit c7734c6fbb5513b4da6306de7bc85de9b8547988, and would like to push
> to master branch once other pending GCC patches have been accepted.
>
>
> The OpenACC XFAILs: "[...] overflows the stack for nvptx offloading"
> are unresolved at this point; see the discussion around
> "Handling of large stack objects in GPU code generation -- maybe transform
> into heap allocation?",
> and my "nvptx: '-mframe-malloc-threshold', '-Wframe-malloc-threshold'"
> experimenting. (The latter works to some extent, but also has other
> issues that I shall detail at some later point in time.)
I had a note from Tobias to "update the the last but one bullet point at
https://gcc.gnu.org/onlinedocs/libgomp/nvptx.html";. Thus pushed to
devel/omp/gcc-12 branch commit 8c29332e98ca4669a059ebc0d90903b409ae049f
"Update 'libgomp/libgomp.texi' for 'nvptx, libgfortran: Switch out of "minimal"
mode'",
see attached. Please consider that one 'fixup'ed into the GCC master
branch submission.
Grüße
Thomas
> From c7734c6fbb5513b4da6306de7bc85de9b8547988 Mon Sep 17 00:00:00 2001
> From: Thomas Schwinge
> Date: Wed, 21 Sep 2022 18:58:34 +0200
> Subject: [PATCH] nvptx, libgfortran: Switch out of "minimal" mode
>
> ..., in order to enable (portions of) Fortran I/O, for example.
>
> libgfortran/ChangeLog:
>
> * configure: Regenerate.
> * configure.ac: No longer set LIBGFOR_MINIMAL for nvptx.
>
> libgomp/ChangeLog:
>
> * testsuite/libgomp.fortran/target-print-1.f90: Adjust.
> * testsuite/libgomp.fortran/target-print-1-nvptx.f90: Remove.
> * testsuite/libgomp.oacc-fortran/print-1.f90: Adjust.
> * testsuite/libgomp.oacc-fortran/print-1-nvptx.f90: Remove.
> * testsuite/libgomp.oacc-fortran/error_stop-2.f: Adjust.
> * testsuite/libgomp.oacc-fortran/stop-2.f: Likewise.
>
> Co-authored-by: Andrew Stubbs
> ---
> libgfortran/ChangeLog.omp | 6 ++
> libgfortran/configure | 17 ++---
> libgfortran/configure.ac| 17 ++---
> libgomp/ChangeLog.omp | 7 +++
> .../libgomp.fortran/target-print-1-nvptx.f90| 11 ---
> .../libgomp.fortran/target-print-1.f90 | 3 ---
> .../libgomp.oacc-fortran/error_stop-2.f | 4 +++-
> .../libgomp.oacc-fortran/print-1-nvptx.f90 | 11 ---
> .../testsuite/libgomp.oacc-fortran/print-1.f90 | 5 ++---
> libgomp/testsuite/libgomp.oacc-fortran/stop-2.f | 4 +++-
> 10 files changed, 33 insertions(+), 52 deletions(-)
> delete mode 100644 libgomp/testsuite/libgomp.fortran/target-print-1-nvptx.f90
> delete mode 100644 libgomp/testsuite/libgomp.oacc-fortran/print-1-nvptx.f90
>
> diff --git a/libgfortran/ChangeLog.omp b/libgfortran/ChangeLog.omp
> index b08c264daf9..925575e65fa 100644
> --- a/libgfortran/ChangeLog.omp
> +++ b/libgfortran/ChangeLog.omp
> @@ -1,3 +1,9 @@
> +2023-01-20 Thomas Schwinge
> + Andrew Stubbs
> +
> + * configure: Regenerate.
> + * configure.ac: No longer set LIBGFOR_MINIMAL for nvptx.
> +
> 2023-01-20 Thomas Schwinge
>
> PR target/85463
> diff --git a/libgfortran/configure b/libgfortran/configure
> index ae64dca3114..3e5c931d4ad 100755
> --- a/libgfortran/configure
> +++ b/libgfortran/configure
> @@ -6230,17 +6230,12 @@ else
> fi
>
>
> -# For GPU offloading, not everything in libfortran can be supported.
> -# Currently, the only target that has this problem is nvptx. The
> -# following is a (partial) list of features that are unsupportable on
> -# this particular target:
> -# * Constructors
> -# * alloca
> -# * C library support for I/O, with printf as the one notable exception
> -# * C library support for other features such as signal, environment
> -# variables, time functions
> -
> - if test "x${target_cpu}" = xnvptx; then
> +# "Minimal" mode is for targets that cannot (yet) support all features of
> +# libgfortran. It avoids the need for working constructors, alloca, and C
> +# library support for I/O, signals, environment variables,
Re: nvptx, libgfortran: Switch out of "minimal" mode
Hi Thomas, On 2023-01-20T22:04:02+0100, I wrote: We've been (t)asked to enable (portions of) GCC/Fortran I/O for nvptx offloading, which means building a normal (non-'LIBGFOR_MINIMAL') configuration of libgfortran. This is achieved by 'nvptx, libgfortran: Switch out of "minimal" mode', see attached, again based on WIP work by Andrew Stubbs. This I've just pushed to devel/omp/gcc-12 branch in commit c7734c6fbb5513b4da6306de7bc85de9b8547988, and would like to push to master branch once other pending GCC patches have been accepted. Looks good to me. Regards Thomas
nvptx, libgfortran: Switch out of "minimal" mode
Hi!
On 2023-01-20T22:04:02+0100, I wrote:
> We've been (t)asked to enable (portions of) GCC/Fortran I/O for nvptx
> offloading, which means building a normal (non-'LIBGFOR_MINIMAL')
> configuration of libgfortran.
This is achieved by 'nvptx, libgfortran: Switch out of "minimal" mode',
see attached, again based on WIP work by Andrew Stubbs. This I've just
pushed to devel/omp/gcc-12 branch in
commit c7734c6fbb5513b4da6306de7bc85de9b8547988, and would like to push
to master branch once other pending GCC patches have been accepted.
The OpenACC XFAILs: "[...] overflows the stack for nvptx offloading"
are unresolved at this point; see the discussion around
"Handling of large stack objects in GPU code generation -- maybe transform into
heap allocation?",
and my "nvptx: '-mframe-malloc-threshold', '-Wframe-malloc-threshold'"
experimenting. (The latter works to some extent, but also has other
issues that I shall detail at some later point in time.)
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
>From c7734c6fbb5513b4da6306de7bc85de9b8547988 Mon Sep 17 00:00:00 2001
From: Thomas Schwinge
Date: Wed, 21 Sep 2022 18:58:34 +0200
Subject: [PATCH] nvptx, libgfortran: Switch out of "minimal" mode
..., in order to enable (portions of) Fortran I/O, for example.
libgfortran/ChangeLog:
* configure: Regenerate.
* configure.ac: No longer set LIBGFOR_MINIMAL for nvptx.
libgomp/ChangeLog:
* testsuite/libgomp.fortran/target-print-1.f90: Adjust.
* testsuite/libgomp.fortran/target-print-1-nvptx.f90: Remove.
* testsuite/libgomp.oacc-fortran/print-1.f90: Adjust.
* testsuite/libgomp.oacc-fortran/print-1-nvptx.f90: Remove.
* testsuite/libgomp.oacc-fortran/error_stop-2.f: Adjust.
* testsuite/libgomp.oacc-fortran/stop-2.f: Likewise.
Co-authored-by: Andrew Stubbs
---
libgfortran/ChangeLog.omp | 6 ++
libgfortran/configure | 17 ++---
libgfortran/configure.ac| 17 ++---
libgomp/ChangeLog.omp | 7 +++
.../libgomp.fortran/target-print-1-nvptx.f90| 11 ---
.../libgomp.fortran/target-print-1.f90 | 3 ---
.../libgomp.oacc-fortran/error_stop-2.f | 4 +++-
.../libgomp.oacc-fortran/print-1-nvptx.f90 | 11 ---
.../testsuite/libgomp.oacc-fortran/print-1.f90 | 5 ++---
libgomp/testsuite/libgomp.oacc-fortran/stop-2.f | 4 +++-
10 files changed, 33 insertions(+), 52 deletions(-)
delete mode 100644 libgomp/testsuite/libgomp.fortran/target-print-1-nvptx.f90
delete mode 100644 libgomp/testsuite/libgomp.oacc-fortran/print-1-nvptx.f90
diff --git a/libgfortran/ChangeLog.omp b/libgfortran/ChangeLog.omp
index b08c264daf9..925575e65fa 100644
--- a/libgfortran/ChangeLog.omp
+++ b/libgfortran/ChangeLog.omp
@@ -1,3 +1,9 @@
+2023-01-20 Thomas Schwinge
+ Andrew Stubbs
+
+ * configure: Regenerate.
+ * configure.ac: No longer set LIBGFOR_MINIMAL for nvptx.
+
2023-01-20 Thomas Schwinge
PR target/85463
diff --git a/libgfortran/configure b/libgfortran/configure
index ae64dca3114..3e5c931d4ad 100755
--- a/libgfortran/configure
+++ b/libgfortran/configure
@@ -6230,17 +6230,12 @@ else
fi
-# For GPU offloading, not everything in libfortran can be supported.
-# Currently, the only target that has this problem is nvptx. The
-# following is a (partial) list of features that are unsupportable on
-# this particular target:
-# * Constructors
-# * alloca
-# * C library support for I/O, with printf as the one notable exception
-# * C library support for other features such as signal, environment
-# variables, time functions
-
- if test "x${target_cpu}" = xnvptx; then
+# "Minimal" mode is for targets that cannot (yet) support all features of
+# libgfortran. It avoids the need for working constructors, alloca, and C
+# library support for I/O, signals, environment variables, time functions, etc.
+# At present there are no targets that require this mode.
+
+ if false; then
LIBGFOR_MINIMAL_TRUE=
LIBGFOR_MINIMAL_FALSE='#'
else
diff --git a/libgfortran/configure.ac b/libgfortran/configure.ac
index 97cc490cb5e..e5552949cc6 100644
--- a/libgfortran/configure.ac
+++ b/libgfortran/configure.ac
@@ -222,17 +222,12 @@ AM_CONDITIONAL(LIBGFOR_USE_SYMVER, [test "x$gfortran_use_symver" != xno])
AM_CONDITIONAL(LIBGFOR_USE_SYMVER_GNU, [test "x$gfortran_use_symver" = xgnu])
AM_CONDITIONAL(LIBGFOR_USE_SYMVER_SUN, [test "x$gfortran_use_symver" = xsun])
-# For GPU offloading, not everything in libfortran can be supported.
-# Currently, the only target that has this p
