Hi, this patch properly handles OpenACC 'wait' clauses without arguments, making it an
equivalent of "wait all".
(current trunk basically discards and ignores such argument-less wait clauses)
This adds additional handling in
the pack/unpack of the wait argument across the compiler/libgomp interface, but
is done in a matter that
doesn't affect binary compatibility.
This patch was part of the OpenACC async re-work that was done on the gomp4
branch (later merged to OG7/OG8), see [1].
I'm separating this part out and submitting it first because it's logically
independent.
[1] https://gcc.gnu.org/ml/gcc-patches/2017-06/msg01842.html
Re-tested with offloading to ensure no regressions, is this okay for trunk?
Thanks,
Chung-Lin
2018-08-30 Chung-Lin Tang <clt...@codesourcery.com>
gcc/c/
* c-parser.c (c_parser_oacc_clause_wait): Add representation of wait
clause without argument as 'wait (GOMP_ASYNC_NOVAL)', adjust comments.
gcc/cp/
* parser.c (cp_parser_oacc_clause_wait): Add representation of wait
clause without argument as 'wait (GOMP_ASYNC_NOVAL)', adjust comments.
gcc/fortran/
* trans-openmp.c (gfc_trans_omp_clauses_1): Add representation of wait
clause without argument as 'wait (GOMP_ASYNC_NOVAL)'.
gcc/
* omp-low.c (expand_omp_target): Add middle-end support for handling
OMP_CLAUSE_WAIT clause with a GOMP_ASYNC_NOVAL(-1) as the argument.
include/
* gomp-constants.h (GOMP_LAUNCH_OP_MASK): Define.
(GOMP_LAUNCH_PACK): Add bitwise-and of GOMP_LAUNCH_OP_MASK.
(GOMP_LAUNCH_OP): Likewise.
libgomp/
* oacc-parallel.c (GOACC_parallel_keyed): Interpret launch op as
signed 16-bit field, adjust num_waits handling.
(GOACC_enter_exit_data): Adjust num_waits handling.
(GOACC_update): Adjust num_waits handling.
Index: gcc/c/c-parser.c
===================================================================
--- gcc/c/c-parser.c (revision 263981)
+++ gcc/c/c-parser.c (working copy)
@@ -12719,7 +12719,7 @@ c_parser_oacc_clause_tile (c_parser *parser, tree
}
/* OpenACC:
- wait ( int-expr-list ) */
+ wait [( int-expr-list )] */
static tree
c_parser_oacc_clause_wait (c_parser *parser, tree list)
@@ -12728,7 +12728,15 @@ c_parser_oacc_clause_wait (c_parser *parser, tree
if (c_parser_peek_token (parser)->type == CPP_OPEN_PAREN)
list = c_parser_oacc_wait_list (parser, clause_loc, list);
+ else
+ {
+ tree c = build_omp_clause (clause_loc, OMP_CLAUSE_WAIT);
+ OMP_CLAUSE_DECL (c) = build_int_cst (integer_type_node,
GOMP_ASYNC_NOVAL);
+ OMP_CLAUSE_CHAIN (c) = list;
+ list = c;
+ }
+
return list;
}
Index: gcc/cp/parser.c
===================================================================
--- gcc/cp/parser.c (revision 263981)
+++ gcc/cp/parser.c (working copy)
@@ -32137,7 +32137,7 @@ cp_parser_oacc_wait_list (cp_parser *parser, locat
}
/* OpenACC:
- wait ( int-expr-list ) */
+ wait [( int-expr-list )] */
static tree
cp_parser_oacc_clause_wait (cp_parser *parser, tree list)
@@ -32144,10 +32144,16 @@ cp_parser_oacc_clause_wait (cp_parser *parser, tre
{
location_t location = cp_lexer_peek_token (parser->lexer)->location;
- if (cp_lexer_peek_token (parser->lexer)->type != CPP_OPEN_PAREN)
- return list;
+ if (cp_lexer_peek_token (parser->lexer)->type == CPP_OPEN_PAREN)
+ list = cp_parser_oacc_wait_list (parser, location, list);
+ else
+ {
+ tree c = build_omp_clause (location, OMP_CLAUSE_WAIT);
- list = cp_parser_oacc_wait_list (parser, location, list);
+ OMP_CLAUSE_DECL (c) = build_int_cst (integer_type_node,
GOMP_ASYNC_NOVAL);
+ OMP_CLAUSE_CHAIN (c) = list;
+ list = c;
+ }
return list;
}
Index: gcc/fortran/trans-openmp.c
===================================================================
--- gcc/fortran/trans-openmp.c (revision 263981)
+++ gcc/fortran/trans-openmp.c (working copy)
@@ -2922,6 +2922,13 @@ gfc_trans_omp_clauses (stmtblock_t *block, gfc_omp
omp_clauses = c;
}
}
+ else if (clauses->wait)
+ {
+ c = build_omp_clause (where.lb->location, OMP_CLAUSE_WAIT);
+ OMP_CLAUSE_DECL (c) = build_int_cst (integer_type_node,
GOMP_ASYNC_NOVAL);
+ OMP_CLAUSE_CHAIN (c) = omp_clauses;
+ omp_clauses = c;
+ }
if (clauses->num_gangs_expr)
{
tree num_gangs_var
Index: gcc/omp-expand.c
===================================================================
--- gcc/omp-expand.c (revision 263981)
+++ gcc/omp-expand.c (working copy)
@@ -7381,16 +7381,32 @@ expand_omp_target (struct omp_region *region)
/* ... push a placeholder. */
args.safe_push (integer_zero_node);
+ bool noval_seen = false;
+ tree noval = build_int_cst (integer_type_node, GOMP_ASYNC_NOVAL);
+
for (; c; c = OMP_CLAUSE_CHAIN (c))
if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_WAIT)
{
+ tree wait_expr = OMP_CLAUSE_WAIT_EXPR (c);
+
+ if (TREE_CODE (wait_expr) == INTEGER_CST
+ && tree_int_cst_compare (wait_expr, noval) == 0)
+ {
+ noval_seen = true;
+ continue;
+ }
+
args.safe_push (fold_convert_loc (OMP_CLAUSE_LOCATION (c),
- integer_type_node,
- OMP_CLAUSE_WAIT_EXPR (c)));
+ integer_type_node, wait_expr));
num_waits++;
}
- if (!tagging || num_waits)
+ if (noval_seen && num_waits == 0)
+ args[t_wait_idx] =
+ (tagging
+ ? oacc_launch_pack (GOMP_LAUNCH_WAIT, NULL_TREE, GOMP_ASYNC_NOVAL)
+ : noval);
+ else if (!tagging || num_waits)
{
tree len;
Index: include/gomp-constants.h
===================================================================
--- include/gomp-constants.h (revision 263981)
+++ include/gomp-constants.h (working copy)
@@ -221,13 +221,14 @@ enum gomp_map_kind
#define GOMP_LAUNCH_CODE_SHIFT 28
#define GOMP_LAUNCH_DEVICE_SHIFT 16
#define GOMP_LAUNCH_OP_SHIFT 0
+#define GOMP_LAUNCH_OP_MASK 0xffff
#define GOMP_LAUNCH_PACK(CODE,DEVICE,OP) \
(((CODE) << GOMP_LAUNCH_CODE_SHIFT) \
| ((DEVICE) << GOMP_LAUNCH_DEVICE_SHIFT) \
- | ((OP) << GOMP_LAUNCH_OP_SHIFT))
+ | (((OP) & GOMP_LAUNCH_OP_MASK) << GOMP_LAUNCH_OP_SHIFT))
#define GOMP_LAUNCH_CODE(X) (((X) >> GOMP_LAUNCH_CODE_SHIFT) & 0xf)
#define GOMP_LAUNCH_DEVICE(X) (((X) >> GOMP_LAUNCH_DEVICE_SHIFT) & 0xfff)
-#define GOMP_LAUNCH_OP(X) (((X) >> GOMP_LAUNCH_OP_SHIFT) & 0xffff)
+#define GOMP_LAUNCH_OP(X) (((X) >> GOMP_LAUNCH_OP_SHIFT) & GOMP_LAUNCH_OP_MASK)
#define GOMP_LAUNCH_OP_MAX 0xffff
/* Bitmask to apply in order to find out the intended device of a target
Index: libgomp/oacc-parallel.c
===================================================================
--- libgomp/oacc-parallel.c (revision 263981)
+++ libgomp/oacc-parallel.c (working copy)
@@ -194,10 +194,14 @@ GOACC_parallel_keyed (int device, void (*fn) (void
case GOMP_LAUNCH_WAIT:
{
- unsigned num_waits = GOMP_LAUNCH_OP (tag);
+ /* Be careful to cast the op field as a signed 16-bit, and
+ sign-extend to full integer. */
+ int num_waits = ((signed short) GOMP_LAUNCH_OP (tag));
- if (num_waits)
+ if (num_waits > 0)
goacc_wait (async, num_waits, &ap);
+ else if (num_waits == acc_async_noval)
+ acc_wait_all_async (async);
break;
}
@@ -351,7 +355,7 @@ GOACC_enter_exit_data (int device, size_t mapnum,
|| host_fallback)
return;
- if (num_waits)
+ if (num_waits > 0)
{
va_list ap;
@@ -359,6 +363,8 @@ GOACC_enter_exit_data (int device, size_t mapnum,
goacc_wait (async, num_waits, &ap);
va_end (ap);
}
+ else if (num_waits == acc_async_noval)
+ acc_wait_all_async (async);
/* Determine whether "finalize" semantics apply to all mappings of this
OpenACC directive. */
@@ -542,7 +548,7 @@ GOACC_update (int device, size_t mapnum,
|| host_fallback)
return;
- if (num_waits)
+ if (num_waits > 0)
{
va_list ap;
@@ -550,6 +556,8 @@ GOACC_update (int device, size_t mapnum,
goacc_wait (async, num_waits, &ap);
va_end (ap);
}
+ else if (num_waits == acc_async_noval)
+ acc_wait_all_async (async);
acc_dev->openacc.async_set_async_func (async);
