diff options
Diffstat (limited to 'gcc/fortran/dependency.c')
-rw-r--r-- | gcc/fortran/dependency.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/gcc/fortran/dependency.c b/gcc/fortran/dependency.c index 96da3c31e4..f764873 100644 --- a/gcc/fortran/dependency.c +++ b/gcc/fortran/dependency.c @@ -359,6 +359,51 @@ gfc_check_fncall_dependency (gfc_expr * other, sym_intent intent, } +/* Return 1 if e1 and e2 are equivalenced arrays, either + directly or indirectly; ie. equivalence (a,b) for a and b + or equivalence (a,c),(b,c). This function uses the equiv_ + lists, generated in trans-common(add_equivalences), that are + guaranteed to pick up indirect equivalences. A rudimentary + use is made of the offset to ensure that cases where the + source elements are moved down to the destination are not + identified as dependencies. */ + +int +gfc_are_equivalenced_arrays (gfc_expr *e1, gfc_expr *e2) +{ + gfc_equiv_list *l; + gfc_equiv_info *s, *fl1, *fl2; + + gcc_assert (e1->expr_type == EXPR_VARIABLE + && e2->expr_type == EXPR_VARIABLE); + + if (!e1->symtree->n.sym->attr.in_equivalence + || !e2->symtree->n.sym->attr.in_equivalence + || !e1->rank + || !e2->rank) + return 0; + + /* Go through the equiv_lists and return 1 if the variables + e1 and e2 are members of the same group and satisfy the + requirement on their relative offsets. */ + for (l = gfc_current_ns->equiv_lists; l; l = l->next) + { + fl1 = NULL; + fl2 = NULL; + for (s = l->equiv; s; s = s->next) + { + if (s->sym == e1->symtree->n.sym) + fl1 = s; + if (s->sym == e2->symtree->n.sym) + fl2 = s; + if (fl1 && fl2 && (fl1->offset > fl2->offset)) + return 1; + } + } +return 0; +} + + /* Return true if the statement body redefines the condition. Returns true if expr2 depends on expr1. expr1 should be a single term suitable for the lhs of an assignment. The IDENTICAL flag indicates @@ -405,6 +450,10 @@ gfc_check_dependency (gfc_expr * expr1, gfc_expr * expr2, bool identical) return 1; } + /* Return 1 if expr1 and expr2 are equivalenced arrays. */ + if (gfc_are_equivalenced_arrays (expr1, expr2)) + return 1; + if (expr1->symtree->n.sym != expr2->symtree->n.sym) return 0; |