https://gcc.gnu.org/g:05c2ad4a2e710494887bcfc334c978c04a6f7994
commit r16-5789-g05c2ad4a2e710494887bcfc334c978c04a6f7994 Author: Paul-Antoine Arras <[email protected]> Date: Fri Nov 28 15:40:44 2025 +0100 OpenMP/Fortran: Allow explicit map followed by implicit deep mapping [PR120505] Consider the following source code, assuming tiles is allocatable: ``` !$omp target enter data map(var%tiles(1)%den1, var%tiles(1)%den2) ! (1) [...] !$omp target ! implicitly maps var, which triggers deep mapping of tiles (2) ``` Each omp directive causes a run-time error in libgomp: (1) libgomp: Mapped array elements must be the same (0x14d729c0 vs 0x14d72a18) (2) libgomp: Trying to map into device [0x3704ca50..0x3704cb00) object when [0x3704ca50..0x3704caa8) is already mapped Regarding (1), the OpenMP spec has the following restriction: "If multiple list items are explicitly mapped on the same construct and have the same containing array or have base pointers that share original storage, and if any of the list items do not have corresponding list items that are present in the device data environment prior to a task encountering the construct, then the list items must refer to *the same array elements* of either the containing array or the implicit array of the base pointers." Because tiles is allocatable, we cannot prove at compile time that array elements are the same, so the check is deferred to libgomp. But there the condition enforcing that all addresses are the same is too strict, so this patch relaxes it to only check that addresses are sorted in increasing order. The OpenMP spec allows (2) as long as it is implicit, without extending the original mapping. So this patch sets the GOMP_MAP_IMPLICIT flag appropriately on deep maps at compile time to let libgomp know that it is fine. This patch ensures that such user code is accepted by: (1) Setting the GOMP_MAP_IMPLICIT flag appropriately on deep maps; (2) Relaxing the restriction on struct mapping from different containing arrays, so that the element index need not be the same, instead addresses must be sorted in increasing order. This fixes the two errors currently seen when running SPEC HPC clvleaf benchmark. However, further mapping issues prevent the benchmark from running to completion. PR fortran/120505 gcc/ChangeLog: * omp-low.cc (lower_omp_target): Set GOMP_MAP_IMPLICIT flag. libgomp/ChangeLog: * target.c (gomp_map_vars_internal): Allow struct mapping from different containing array elements as long as adresses are in increasing order. * testsuite/libgomp.c-c++-common/map-arrayofstruct-2.c: Adjust dg-output. * testsuite/libgomp.c-c++-common/map-arrayofstruct-3.c: Likewise. * testsuite/libgomp.fortran/map-subarray-5.f90: Likewise. * testsuite/libgomp.fortran/map-subarray-10.f90: New test. * testsuite/libgomp.fortran/map-subarray-9.f90: New test. Diff: --- gcc/omp-low.cc | 15 +++++++- libgomp/target.c | 10 +++--- .../libgomp.c-c++-common/map-arrayofstruct-2.c | 2 +- .../libgomp.c-c++-common/map-arrayofstruct-3.c | 2 +- .../testsuite/libgomp.fortran/map-subarray-10.f90 | 40 ++++++++++++++++++++++ .../testsuite/libgomp.fortran/map-subarray-5.f90 | 2 +- .../testsuite/libgomp.fortran/map-subarray-9.f90 | 40 ++++++++++++++++++++++ 7 files changed, 102 insertions(+), 9 deletions(-) diff --git a/gcc/omp-low.cc b/gcc/omp-low.cc index d36756e33a5a..6fd685cdecd3 100644 --- a/gcc/omp-low.cc +++ b/gcc/omp-low.cc @@ -13240,7 +13240,20 @@ lower_omp_target (gimple_stmt_iterator *gsi_p, omp_context *ctx) unsigned HOST_WIDE_INT tkind2; switch (OMP_CLAUSE_CODE (c)) { - case OMP_CLAUSE_MAP: tkind2 = OMP_CLAUSE_MAP_KIND (c); break; + case OMP_CLAUSE_MAP: + tkind2 = OMP_CLAUSE_MAP_KIND (c); + if (OMP_CLAUSE_MAP_RUNTIME_IMPLICIT_P (c) + && (((tkind2 & GOMP_MAP_FLAG_SPECIAL_BITS) + & ~GOMP_MAP_IMPLICIT) + == 0)) + { + /* If this is an implicit map, and the GOMP_MAP_IMPLICIT + bits are not interfered by other special bit + encodings, then turn the GOMP_IMPLICIT_BIT flag on + for the runtime to see. */ + tkind2 |= GOMP_MAP_IMPLICIT; + } + break; case OMP_CLAUSE_FIRSTPRIVATE: tkind2 = GOMP_MAP_TO; break; case OMP_CLAUSE_TO: tkind2 = GOMP_MAP_TO; break; case OMP_CLAUSE_FROM: tkind2 = GOMP_MAP_FROM; break; diff --git a/libgomp/target.c b/libgomp/target.c index 49d4218b1f7f..af7c702d439e 100644 --- a/libgomp/target.c +++ b/libgomp/target.c @@ -1665,14 +1665,14 @@ gomp_map_vars_internal (struct gomp_device_descr *devicep, case GOMP_MAP_STRUCT_UNORD: if (sizes[i] > 1) { - void *first = hostaddrs[i + 1]; for (size_t j = i + 1; j < i + sizes[i]; j++) - if (hostaddrs[j + 1] != first) + if (hostaddrs[j + 1] < hostaddrs[j]) { gomp_mutex_unlock (&devicep->lock); - gomp_fatal ("Mapped array elements must be the " - "same (%p vs %p)", first, - hostaddrs[j + 1]); + gomp_fatal ( + "Mapped array elements must be the same or in " + "increasing address order (got %p > %p)", + hostaddrs[j], hostaddrs[j + 1]); } } /* Fallthrough. */ diff --git a/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-2.c b/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-2.c index ff7ce0eb1622..55bd60772a07 100644 --- a/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-2.c +++ b/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-2.c @@ -54,5 +54,5 @@ int main (void) } /* { dg-output "(\n|\r|\r\n)" { target offload_device_nonshared_as } } */ -/* { dg-output "libgomp: Mapped array elements must be the same .*(\n|\r|\r\n)+" { target offload_device_nonshared_as } } */ +/* { dg-output "libgomp: Mapped array elements must be the same or in increasing address order .*(\n|\r|\r\n)+" { target offload_device_nonshared_as } } */ /* { dg-shouldfail "" { offload_device_nonshared_as } } */ diff --git a/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-3.c b/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-3.c index 770ac2ae1aa6..0352682d042e 100644 --- a/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-3.c +++ b/libgomp/testsuite/libgomp.c-c++-common/map-arrayofstruct-3.c @@ -64,5 +64,5 @@ int main (void) } /* { dg-output "(\n|\r|\r\n)" { target offload_device_nonshared_as } } */ -/* { dg-output "libgomp: Mapped array elements must be the same .*(\n|\r|\r\n)+" { target offload_device_nonshared_as } } */ +/* { dg-output "libgomp: Mapped array elements must be the same or in increasing address order .*(\n|\r|\r\n)+" { target offload_device_nonshared_as } } */ /* { dg-shouldfail "" { offload_device_nonshared_as } } */ diff --git a/libgomp/testsuite/libgomp.fortran/map-subarray-10.f90 b/libgomp/testsuite/libgomp.fortran/map-subarray-10.f90 new file mode 100644 index 000000000000..9afb84588496 --- /dev/null +++ b/libgomp/testsuite/libgomp.fortran/map-subarray-10.f90 @@ -0,0 +1,40 @@ +! { dg-do run } + +! PR fortran/120505 + +! This test case checks that explicit mapping of allocatable DT components from +! different containing array elements followed by implicit deep mapping works. + +module m +type t + integer, allocatable :: den1(:,:), den2(:,:) +end type t + +type t2 + type(t), allocatable :: tiles(:) +end type t2 + +type(t2) :: var +end + +use m + +allocate(var%tiles(2)) +var%tiles(1)%den1 = reshape([1,2,3,4],[2,2]) +var%tiles(2)%den2 = reshape([11,22,33,44],[2,2]) + +!$omp target enter data map(var%tiles(1)%den1, var%tiles(2)%den2) + +!$omp target + if (any (var%tiles(1)%den1 /= reshape([1,2,3,4],[2,2]))) stop 1 + if (any (var%tiles(2)%den2 /= reshape([11,22,33,44],[2,2]))) stop 1 + var%tiles(1)%den1 = var%tiles(1)%den1 + 5 + var%tiles(2)%den2 = var%tiles(2)%den2 + 7 +!$omp end target + +!$omp target exit data map(var%tiles(1)%den1, var%tiles(2)%den2) + +if (any (var%tiles(1)%den1 /= 5 + reshape([1,2,3,4],[2,2]))) stop 1 +if (any (var%tiles(2)%den2 /= 7 + reshape([11,22,33,44],[2,2]))) stop 1 + +end diff --git a/libgomp/testsuite/libgomp.fortran/map-subarray-5.f90 b/libgomp/testsuite/libgomp.fortran/map-subarray-5.f90 index 59ad01ab76be..7bf3102018e7 100644 --- a/libgomp/testsuite/libgomp.fortran/map-subarray-5.f90 +++ b/libgomp/testsuite/libgomp.fortran/map-subarray-5.f90 @@ -50,5 +50,5 @@ end do end ! { dg-output "(\n|\r|\r\n)" { target offload_device_nonshared_as } } -! { dg-output "libgomp: Mapped array elements must be the same .*(\n|\r|\r\n)+" { target offload_device_nonshared_as } } +! { dg-output "libgomp: Mapped array elements must be the same or in increasing address order .*(\n|\r|\r\n)+" { target offload_device_nonshared_as } } ! { dg-shouldfail "" { offload_device_nonshared_as } } diff --git a/libgomp/testsuite/libgomp.fortran/map-subarray-9.f90 b/libgomp/testsuite/libgomp.fortran/map-subarray-9.f90 new file mode 100644 index 000000000000..f31015599037 --- /dev/null +++ b/libgomp/testsuite/libgomp.fortran/map-subarray-9.f90 @@ -0,0 +1,40 @@ +! { dg-do run } + +! PR fortran/120505 + +! This test case checks that explicit mapping of allocatable DT components +! followed by implicit deep mapping works. + +module m +type t + integer, allocatable :: den1(:,:), den2(:,:) +end type t + +type t2 + type(t), allocatable :: tiles(:) +end type t2 + +type(t2) :: var +end + +use m + +allocate(var%tiles(1)) +var%tiles(1)%den1 = reshape([1,2,3,4],[2,2]) +var%tiles(1)%den2 = reshape([11,22,33,44],[2,2]) + +!$omp target enter data map(var%tiles(1)%den1, var%tiles(1)%den2) + +!$omp target + if (any (var%tiles(1)%den1 /= reshape([1,2,3,4],[2,2]))) stop 1 + if (any (var%tiles(1)%den2 /= reshape([11,22,33,44],[2,2]))) stop 1 + var%tiles(1)%den1 = var%tiles(1)%den1 + 5 + var%tiles(1)%den2 = var%tiles(1)%den2 + 7 +!$omp end target + +!$omp target exit data map(var%tiles(1)%den1, var%tiles(1)%den2) + +if (any (var%tiles(1)%den1 /= 5 + reshape([1,2,3,4],[2,2]))) stop 1 +if (any (var%tiles(1)%den2 /= 7 + reshape([11,22,33,44],[2,2]))) stop 1 + +end
