OpenMP mandates that when certain clauses are used with 'omp requires'
that in all compilation units this requires clause appears.
Those clauses influence the offloading behavior (+ potentially codegen);
hence, the must requires must match for those claues when device code is
involved. That's the case for device functions (in particular 'declare
target') and all OpenMP directives that take a 'device' clause.
Before OpenMP was rather vague, but in .e.g. TR13, it is fortunally more
explicit. Thus, this patch adds it for 'declare target' and it adds it
("device" clause!) for 'interop' (but only for Fortran as C/C++ still
does not support 'interop' directive plarsing.)
And comment before I commit it?
Tobias
PS: In TR13, page 321, lines 14–16 —
https://www.openmp.org/wp-content/uploads/openmp-TR13.pdf
OpenMP: Update OMP_REQUIRES_TARGET_USED for declare_target + interop
Older versions of the OpenMP specification were not clear about what counted
as device usage. Newer (like TR13) are rather clear. Hence, this commit adds
"target used" also when 'declare target' or 'interop' are encountered.
(The latter only to Fortran as C/C++ parsing support is still missing.)
TR13 also lists 'dispatch' as construct and 'device_safesync' affected by
device use, but both are not yet supported in GCC:
gcc/c/ChangeLog:
* c-parser.cc (c_parser_omp_declare_target): Set target-used bit
in omp_requires_mask.
gcc/cp/ChangeLog:
* parser.cc (cp_parser_omp_declare_target): Set target-used bit
in omp_requires_mask.
gcc/fortran/ChangeLog:
* parse.cc (decode_omp_directive): Set target-used bit of
omp_requires_mask when encountering the declare_target or interop
directive.
gcc/c/c-parser.cc | 3 +++
gcc/cp/parser.cc | 3 +++
gcc/fortran/parse.cc | 8 ++++++--
3 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/gcc/c/c-parser.cc b/gcc/c/c-parser.cc
index 6a46577f511..a681438cbbe 100644
--- a/gcc/c/c-parser.cc
+++ b/gcc/c/c-parser.cc
@@ -25492,6 +25492,9 @@ c_parser_omp_declare_target (c_parser *parser)
int device_type = 0;
bool indirect = false;
bool only_device_type_or_indirect = true;
+ if (flag_openmp)
+ omp_requires_mask
+ = (enum omp_requires) (omp_requires_mask | OMP_REQUIRES_TARGET_USED);
if (c_parser_next_token_is (parser, CPP_NAME)
|| (c_parser_next_token_is (parser, CPP_COMMA)
&& c_parser_peek_2nd_token (parser)->type == CPP_NAME))
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 35c266659e4..3b3ab0f1923 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -49524,6 +49524,9 @@ cp_parser_omp_declare_target (cp_parser *parser, cp_token *pragma_tok)
int device_type = 0;
bool indirect = false;
bool only_device_type_or_indirect = true;
+ if (flag_openmp)
+ omp_requires_mask
+ = (enum omp_requires) (omp_requires_mask | OMP_REQUIRES_TARGET_USED);
if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)
|| (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)
&& cp_lexer_nth_token_is (parser->lexer, 2, CPP_NAME)))
diff --git a/gcc/fortran/parse.cc b/gcc/fortran/parse.cc
index e749bbdc6b5..9e06dbf0911 100644
--- a/gcc/fortran/parse.cc
+++ b/gcc/fortran/parse.cc
@@ -1345,8 +1345,12 @@ decode_omp_directive (void)
switch (ret)
{
- /* Set omp_target_seen; exclude ST_OMP_DECLARE_TARGET.
- FIXME: Get clarification, cf. OpenMP Spec Issue #3240. */
+ /* For the constraints on clauses with the global requirement property,
+ we set omp_target_seen. This included all clauses that take the
+ DEVICE clause, (BEGIN) DECLARE_TARGET and procedures run the device
+ (which effectively is implied by the former). */
+ case ST_OMP_DECLARE_TARGET:
+ case ST_OMP_INTEROP:
case ST_OMP_TARGET:
case ST_OMP_TARGET_DATA:
case ST_OMP_TARGET_ENTER_DATA:
