Skip to content

R
riscv-gcc-1
Commit 8b7cec58 by Thomas Koenig
Options

re PR fortran/47674 (gfortran.dg/realloc_on_assign_5.f03: Segfault at run time… 

re PR fortran/47674 (gfortran.dg/realloc_on_assign_5.f03: Segfault at run time for deferred (allocatable) string length)

2015-01-05  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/47674
	* dependency.c:  Update copyright years.
	(gfc_discard_nops):  Add prototype.
	* dependency.c (discard_nops):  Rename to gfc_discard_nops,
	make non-static.
	(gfc_discard_nops):  Use gfc_discard_nops.
	(gfc_dep_difference):  Likewise.
	* frontend-passes.c  Update copyright years.
	(realloc_strings):  New function.  Add prototype.
	(gfc_run_passes):  Call realloc_strings.
	(realloc_string_callback):  New function.
	(create_var):  Add prototype.  Handle case of a
	scalar character variable.
	(optimize_trim):  Do not handle allocatable variables.

2015-01-05  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/47674
	* gfortran.dg/realloc_on_assign_25.f90:  New test.

From-SVN: r219193
parent 24fa8749
Showing with 198 additions and 24 deletions
gcc/fortran/ChangeLog
2015-01-05 Thomas Koenig <tkoenig@gcc.gnu.org>
PR fortran/47674
* dependency.c: Update copyright years.
(gfc_discard_nops): Add prototype.
* dependency.c (discard_nops): Rename to gfc_discard_nops,
make non-static.
(gfc_discard_nops): Use gfc_discard_nops.
(gfc_dep_difference): Likewise.
* frontend-passes.c Update copyright years.
(realloc_strings): New function. Add prototype.
(gfc_run_passes): Call realloc_strings.
(realloc_string_callback): New function.
(create_var): Add prototype. Handle case of a
scalar character variable.
(optimize_trim): Do not handle allocatable variables.
2015-01-05 Jakub Jelinek <jakub@redhat.com>
Update copyright years.
......
gcc/fortran/dependency.c
......@@ -243,8 +243,8 @@ gfc_dep_compare_functions (gfc_expr *e1, gfc_expr *e2, bool impure_ok)
/* Helper function to look through parens, unary plus and widening
integer conversions. */
static gfc_expr*
discard_nops (gfc_expr *e)
gfc_expr *
gfc_discard_nops (gfc_expr *e)
{
gfc_actual_arglist *arglist;
......@@ -297,8 +297,8 @@ gfc_dep_compare_expr (gfc_expr *e1, gfc_expr *e2)
if (e1 == NULL && e2 == NULL)
return 0;
e1 = discard_nops (e1);
e2 = discard_nops (e2);
e1 = gfc_discard_nops (e1);
e2 = gfc_discard_nops (e2);
if (e1->expr_type == EXPR_OP && e1->value.op.op == INTRINSIC_PLUS)
{
......@@ -515,8 +515,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e1->ts.type != BT_INTEGER || e2->ts.type != BT_INTEGER)
return false;
e1 = discard_nops (e1);
e2 = discard_nops (e2);
e1 = gfc_discard_nops (e1);
e2 = gfc_discard_nops (e2);
/* Inizialize tentatively, clear if we don't return anything. */
mpz_init (*result);
......@@ -531,8 +531,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e1->expr_type == EXPR_OP && e1->value.op.op == INTRINSIC_PLUS)
{
e1_op1 = discard_nops (e1->value.op.op1);
e1_op2 = discard_nops (e1->value.op.op2);
e1_op1 = gfc_discard_nops (e1->value.op.op1);
e1_op2 = gfc_discard_nops (e1->value.op.op2);
/* Case 2: (X + c1) - X = c1. */
if (e1_op2->expr_type == EXPR_CONSTANT
......@@ -552,8 +552,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e2->expr_type == EXPR_OP && e2->value.op.op == INTRINSIC_PLUS)
{
e2_op1 = discard_nops (e2->value.op.op1);
e2_op2 = discard_nops (e2->value.op.op2);
e2_op1 = gfc_discard_nops (e2->value.op.op1);
e2_op2 = gfc_discard_nops (e2->value.op.op2);
if (e1_op2->expr_type == EXPR_CONSTANT)
{
......@@ -597,8 +597,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e2->expr_type == EXPR_OP && e2->value.op.op == INTRINSIC_MINUS)
{
e2_op1 = discard_nops (e2->value.op.op1);
e2_op2 = discard_nops (e2->value.op.op2);
e2_op1 = gfc_discard_nops (e2->value.op.op1);
e2_op2 = gfc_discard_nops (e2->value.op.op2);
if (e1_op2->expr_type == EXPR_CONSTANT)
{
......@@ -627,8 +627,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e1->expr_type == EXPR_OP && e1->value.op.op == INTRINSIC_MINUS)
{
e1_op1 = discard_nops (e1->value.op.op1);
e1_op2 = discard_nops (e1->value.op.op2);
e1_op1 = gfc_discard_nops (e1->value.op.op1);
e1_op2 = gfc_discard_nops (e1->value.op.op2);
if (e1_op2->expr_type == EXPR_CONSTANT)
{
......@@ -642,8 +642,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e2->expr_type == EXPR_OP && e2->value.op.op == INTRINSIC_PLUS)
{
e2_op1 = discard_nops (e2->value.op.op1);
e2_op2 = discard_nops (e2->value.op.op2);
e2_op1 = gfc_discard_nops (e2->value.op.op1);
e2_op2 = gfc_discard_nops (e2->value.op.op2);
/* Case 11: (X - c1) - (X + c2) = -( c1 + c2). */
if (e2_op2->expr_type == EXPR_CONSTANT
......@@ -668,8 +668,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e2->expr_type == EXPR_OP && e2->value.op.op == INTRINSIC_MINUS)
{
e2_op1 = discard_nops (e2->value.op.op1);
e2_op2 = discard_nops (e2->value.op.op2);
e2_op1 = gfc_discard_nops (e2->value.op.op1);
e2_op2 = gfc_discard_nops (e2->value.op.op2);
/* Case 13: (X - c1) - (X - c2) = c2 - c1. */
if (e2_op2->expr_type == EXPR_CONSTANT
......@@ -685,8 +685,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
{
if (e2->expr_type == EXPR_OP && e2->value.op.op == INTRINSIC_MINUS)
{
e2_op1 = discard_nops (e2->value.op.op1);
e2_op2 = discard_nops (e2->value.op.op2);
e2_op1 = gfc_discard_nops (e2->value.op.op1);
e2_op2 = gfc_discard_nops (e2->value.op.op2);
/* Case 14: (c1 - X) - (c2 - X) == c1 - c2. */
if (gfc_dep_compare_expr (e1_op2, e2_op2) == 0)
......@@ -702,8 +702,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e2->expr_type == EXPR_OP && e2->value.op.op == INTRINSIC_PLUS)
{
e2_op1 = discard_nops (e2->value.op.op1);
e2_op2 = discard_nops (e2->value.op.op2);
e2_op1 = gfc_discard_nops (e2->value.op.op1);
e2_op2 = gfc_discard_nops (e2->value.op.op2);
/* Case 15: X - (X + c2) = -c2. */
if (e2_op2->expr_type == EXPR_CONSTANT
......@@ -723,8 +723,8 @@ gfc_dep_difference (gfc_expr *e1, gfc_expr *e2, mpz_t *result)
if (e2->expr_type == EXPR_OP && e2->value.op.op == INTRINSIC_MINUS)
{
e2_op1 = discard_nops (e2->value.op.op1);
e2_op2 = discard_nops (e2->value.op.op2);
e2_op1 = gfc_discard_nops (e2->value.op.op1);
e2_op2 = gfc_discard_nops (e2->value.op.op2);
/* Case 17: X - (X - c2) = c2. */
if (e2_op2->expr_type == EXPR_CONSTANT
......
gcc/fortran/frontend-passes.c
......@@ -42,6 +42,8 @@ static bool is_empty_string (gfc_expr *e);
static void doloop_warn (gfc_namespace *);
static void optimize_reduction (gfc_namespace *);
static int callback_reduction (gfc_expr **, int *, void *);
static void realloc_strings (gfc_namespace *);
static gfc_expr *create_var (gfc_expr *);
/* How deep we are inside an argument list. */
......@@ -113,6 +115,51 @@ gfc_run_passes (gfc_namespace *ns)
expr_array.release ();
}
if (flag_realloc_lhs)
realloc_strings (ns);
}
/* Callback for each gfc_code node invoked from check_realloc_strings.
For an allocatable LHS string which also appears as a variable on
the RHS, replace
a = a(x:y)
with
tmp = a(x:y)
a = tmp
*/
static int
realloc_string_callback (gfc_code **c, int *walk_subtrees,
void *data ATTRIBUTE_UNUSED)
{
gfc_expr *expr1, *expr2;
gfc_code *co = *c;
gfc_expr *n;
*walk_subtrees = 0;
if (co->op != EXEC_ASSIGN)
return 0;
expr1 = co->expr1;
if (expr1->ts.type != BT_CHARACTER || expr1->rank != 0
|| !expr1->symtree->n.sym->attr.allocatable)
return 0;
expr2 = gfc_discard_nops (co->expr2);
if (expr2->expr_type != EXPR_VARIABLE)
return 0;
if (!gfc_check_dependency (expr1, expr2, true))
return 0;
current_code = c;
n = create_var (expr2);
co->expr2 = n;
return 0;
}
/* Callback for each gfc_code node invoked through gfc_code_walker
......@@ -430,6 +477,52 @@ is_fe_temp (gfc_expr *e)
return e->symtree->n.sym->attr.fe_temp;
}
/* Determine the length of a string, if it can be evaluated as a constant
expression. Return a newly allocated gfc_expr or NULL on failure.
If the user specified a substring which is potentially longer than
the string itself, the string will be padded with spaces, which
is harmless. */
static gfc_expr *
constant_string_length (gfc_expr *e)
{
gfc_expr *length;
gfc_ref *ref;
gfc_expr *res;
mpz_t value;
if (e->ts.u.cl)
{
length = e->ts.u.cl->length;
if (length && length->expr_type == EXPR_CONSTANT)
return gfc_copy_expr(length);
}
/* Return length of substring, if constant. */
for (ref = e->ref; ref; ref = ref->next)
{
if (ref->type == REF_SUBSTRING
&& gfc_dep_difference (ref->u.ss.end, ref->u.ss.start, &value))
{
res = gfc_get_constant_expr (BT_INTEGER, gfc_charlen_int_kind,
&e->where);
mpz_add_ui (res->value.integer, value, 1);
mpz_clear (value);
return res;
}
}
/* Return length of char symbol, if constant. */
if (e->symtree->n.sym->ts.u.cl && e->symtree->n.sym->ts.u.cl->length
&& e->symtree->n.sym->ts.u.cl->length->expr_type == EXPR_CONSTANT)
return gfc_copy_expr (e->symtree->n.sym->ts.u.cl->length);
return NULL;
}
/* Returns a new expression (a variable) to be used in place of the old one,
with an assignment statement before the current statement to set
......@@ -525,6 +618,20 @@ create_var (gfc_expr * e)
}
}
if (e->ts.type == BT_CHARACTER && e->rank == 0)
{
gfc_expr *length;
length = constant_string_length (e);
if (length)
{
symbol->ts.u.cl = gfc_new_charlen (ns, NULL);
symbol->ts.u.cl->length = length;
}
else
symbol->attr.allocatable = 1;
}
symbol->attr.flavor = FL_VARIABLE;
symbol->attr.referenced = 1;
symbol->attr.dimension = e->rank > 0;
......@@ -849,6 +956,26 @@ optimize_namespace (gfc_namespace *ns)
}
}
/* Handle dependencies for allocatable strings which potentially redefine
themselves in an assignment. */
static void
realloc_strings (gfc_namespace *ns)
{
current_ns = ns;
gfc_code_walker (&ns->code, realloc_string_callback, dummy_expr_callback, NULL);
for (ns = ns->contained; ns; ns = ns->sibling)
{
if (ns->code == NULL || ns->code->op != EXEC_BLOCK)
{
// current_ns = ns;
realloc_strings (ns);
}
}
}
static void
optimize_reduction (gfc_namespace *ns)
{
......@@ -1567,6 +1694,11 @@ optimize_trim (gfc_expr *e)
if (a->expr_type != EXPR_VARIABLE)
return false;
/* This would pessimize the idiom a = trim(a) for reallocatable strings. */
if (a->symtree->n.sym->attr.allocatable)
return false;
/* Follow all references to find the correct place to put the newly
created reference. FIXME: Also handle substring references and
array references. Array references cause strange regressions at
......
gcc/testsuite/ChangeLog
2015-01-05 Thomas Koenig <tkoenig@gcc.gnu.org>
PR fortran/47674
* gfortran.dg/realloc_on_assign_25.f90: New test.
2015-01-05 Jakub Jelinek <jakub@redhat.com>
Update copyright years.
......
gcc/testsuite/gfortran.dg/realloc_on_assign_25.f90 0 → 100644
! { dg-do run }
! PR 47674 - this would segfault if MALLOC_PERTURB is set.
! This checks a code path where it is not possible to determine
! the length of the string at compile time.
!
program main
implicit none
character(:), allocatable :: a
integer :: m, n
a = 'a'
if (a .ne. 'a') call abort
a = a // 'x'
if (a .ne. 'ax') call abort
if (len (a) .ne. 2) call abort
n = 2
m = 2
a = a(m:n)
if (a .ne. 'x') call abort
if (len (a) .ne. 1) call abort
end program main
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment