Hi!
Similarly to EXEC_OMP_WORKSHARE, EXEC_OMP_ATOMIC has also very tight rules
what can and can't appear in the block, enforced through parsing and
resolving, so e.g. inserting EXEC_BLOCK there leads to ICEs. In theory, one
could add such a BLOCK around the atomic rather than inside of it, but the
code isn't prepared to be able to do that and furthermore there is still
risk of breaking the EXEC_OMP_ATOMIC expectations.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux,
committed to trunk so far.
2019-12-19 Jakub Jelinek <ja...@redhat.com>
PR fortran/92977
* frontend-passes.c (in_omp_atomic): New variable.
(cfe_expr_0, matmul_to_var_expr, matmul_temp_args,
inline_matmul_assign, call_external_blas): Don't optimize in
EXEC_OMP_ATOMIC.
(optimize_namespace): Clear in_omp_atomic.
(gfc_code_walker): Set in_omp_atomic for EXEC_OMP_ATOMIC, save/restore
it around.
* gfortran.dg/gomp/pr92977.f90: New test.
--- gcc/fortran/frontend-passes.c.jj 2019-11-09 18:08:47.866374726 +0100
+++ gcc/fortran/frontend-passes.c 2019-12-18 14:45:23.996493420 +0100
@@ -92,6 +92,10 @@ static int forall_level;
static bool in_omp_workshare;
+/* Keep track of whether we are within an OMP atomic. */
+
+static bool in_omp_atomic;
+
/* Keep track of whether we are within a WHERE statement. */
static bool in_where;
@@ -913,9 +917,9 @@ cfe_expr_0 (gfc_expr **e, int *walk_subt
gfc_expr *newvar;
gfc_expr **ei, **ej;
- /* Don't do this optimization within OMP workshare or ASSOC lists. */
+ /* Don't do this optimization within OMP workshare/atomic or ASSOC lists. */
- if (in_omp_workshare || in_assoc_list)
+ if (in_omp_workshare || in_omp_atomic || in_assoc_list)
{
*walk_subtrees = 0;
return 0;
@@ -1464,6 +1468,7 @@ optimize_namespace (gfc_namespace *ns)
iterator_level = 0;
in_assoc_list = false;
in_omp_workshare = false;
+ in_omp_atomic = false;
if (flag_frontend_optimize)
{
@@ -2818,7 +2823,7 @@ matmul_to_var_expr (gfc_expr **ep, int *
return 0;
if (forall_level > 0 || iterator_level > 0 || in_omp_workshare
- || in_where || in_assoc_list)
+ || in_omp_atomic || in_where || in_assoc_list)
return 0;
/* Check if this is already in the form c = matmul(a,b). */
@@ -2880,7 +2885,7 @@ matmul_temp_args (gfc_code **c, int *wal
return 0;
if (forall_level > 0 || iterator_level > 0 || in_omp_workshare
- || in_where)
+ || in_omp_atomic || in_where)
return 0;
/* This has some duplication with inline_matmul_assign. This
@@ -3848,7 +3853,7 @@ inline_matmul_assign (gfc_code **c, int
/* For now don't do anything in OpenMP workshare, it confuses
its translation, which expects only the allowed statements in there.
We should figure out how to parallelize this eventually. */
- if (in_omp_workshare)
+ if (in_omp_workshare || in_omp_atomic)
return 0;
expr1 = co->expr1;
@@ -4385,7 +4390,7 @@ call_external_blas (gfc_code **c, int *w
/* For now don't do anything in OpenMP workshare, it confuses
its translation, which expects only the allowed statements in there. */
- if (in_omp_workshare)
+ if (in_omp_workshare | in_omp_atomic)
return 0;
expr1 = co->expr1;
@@ -5047,6 +5052,7 @@ gfc_code_walker (gfc_code **c, walk_code
gfc_code *co;
gfc_association_list *alist;
bool saved_in_omp_workshare;
+ bool saved_in_omp_atomic;
bool saved_in_where;
/* There might be statement insertions before the current code,
@@ -5054,6 +5060,7 @@ gfc_code_walker (gfc_code **c, walk_code
co = *c;
saved_in_omp_workshare = in_omp_workshare;
+ saved_in_omp_atomic = in_omp_atomic;
saved_in_where = in_where;
switch (co->op)
@@ -5251,6 +5258,10 @@ gfc_code_walker (gfc_code **c, walk_code
WALK_SUBEXPR (co->ext.dt->extra_comma);
break;
+ case EXEC_OMP_ATOMIC:
+ in_omp_atomic = true;
+ break;
+
case EXEC_OMP_PARALLEL:
case EXEC_OMP_PARALLEL_DO:
case EXEC_OMP_PARALLEL_DO_SIMD:
@@ -5368,6 +5379,7 @@ gfc_code_walker (gfc_code **c, walk_code
select_level --;
in_omp_workshare = saved_in_omp_workshare;
+ in_omp_atomic = saved_in_omp_atomic;
in_where = saved_in_where;
}
}
--- gcc/testsuite/gfortran.dg/gomp/pr92977.f90.jj 2019-12-18
15:16:14.657486591 +0100
+++ gcc/testsuite/gfortran.dg/gomp/pr92977.f90 2019-12-18 15:16:08.310582750
+0100
@@ -0,0 +1,15 @@
+! PR fortran/92977
+! { dg-do compile }
+! { dg-additional-options "-O2" }
+
+program pr92977
+ integer :: n = 1
+ integer :: a
+!$omp atomic write
+ a = f(n) - f(n)
+contains
+ integer function f(x)
+ integer, intent(in) :: x
+ f = x
+ end
+end
Jakub
