re PR tree-optimization/57149 (wrong -Wmaybe-uninitialized warning with -Os)

PR tree-optimization/57149
	* tree-ssa-uninit.c (uninit_undefined_value_p): New inline.
	(can_skip_redundant_opnd, compute_uninit_opnds_pos,
	collect_phi_def_edges, execute_late_warn_uninitialized): Use
	uninit_undefined_value_p instead of ssa_undefined_value_p.

	* gcc.dg/pr57149.c: New test.

From-SVN: r198671
This commit is contained in:
Jakub Jelinek 2013-05-07 12:30:13 +02:00 committed by Jakub Jelinek
parent 43303d6f8e
commit ba7e83f8dc
4 changed files with 76 additions and 4 deletions

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@ -1,5 +1,11 @@
2013-05-07 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/57149
* tree-ssa-uninit.c (uninit_undefined_value_p): New inline.
(can_skip_redundant_opnd, compute_uninit_opnds_pos,
collect_phi_def_edges, execute_late_warn_uninitialized): Use
uninit_undefined_value_p instead of ssa_undefined_value_p.
PR debug/57184
* expr.c (expand_expr_addr_expr_1): Handle COMPOUND_LITERAL_EXPR
for modifier == EXPAND_INITIALIZER.

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@ -1,5 +1,8 @@
2013-05-07 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/57149
* gcc.dg/pr57149.c: New test.
PR debug/57184
* gcc.dg/pr57184.c: New test.

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@ -0,0 +1,50 @@
/* PR tree-optimization/57149 */
/* { dg-do compile } */
/* { dg-options "-Os -Wuninitialized" } */
struct A { struct A *a, *b; };
struct D { struct A e; };
struct E { unsigned char f; struct { struct A e; } g; };
struct F { struct E i[32]; };
extern int fn0 (void);
extern int fn1 (struct E *, struct D *);
static inline __attribute__ ((always_inline)) int
fn2 (const struct A *x)
{
return x->a == x;
}
static int
fn3 (struct E *x)
{
struct D *l, *m;
int retval = retval;
if (fn2 (&x->g.e))
return 0;
for (l = (struct D *) x->g.e.a, m = (struct D *) l->e.a;
&l->e != &x->g.e;
l = m, m = (struct D *) m->e.a)
retval = fn1 (x, l);
return retval;
}
void
fn4 (struct F *x, unsigned k)
{
unsigned i;
for (i = 0; i < k; i++)
{
struct E *y = &x->i[i];
int err = -22;
err = fn3 (y);
if (y->f == 0)
{
if (err > 0)
err = fn0 ();
if (err < 0) /* { dg-bogus "may be used uninitialized in this function" } */
fn0 ();
}
}
}

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@ -101,6 +101,19 @@ ssa_undefined_value_p (tree t)
&& pointer_set_contains (possibly_undefined_names, t)));
}
/* Like ssa_undefined_value_p, but don't return true if TREE_NO_WARNING
is set on SSA_NAME_VAR. */
static inline bool
uninit_undefined_value_p (tree t)
{
if (!ssa_undefined_value_p (t))
return false;
if (SSA_NAME_VAR (t) && TREE_NO_WARNING (SSA_NAME_VAR (t)))
return false;
return true;
}
/* Checks if the operand OPND of PHI is defined by
another phi with one operand defined by this PHI,
but the rest operands are all defined. If yes,
@ -124,7 +137,7 @@ can_skip_redundant_opnd (tree opnd, gimple phi)
tree op = gimple_phi_arg_def (op_def, i);
if (TREE_CODE (op) != SSA_NAME)
continue;
if (op != phi_def && ssa_undefined_value_p (op))
if (op != phi_def && uninit_undefined_value_p (op))
return false;
}
@ -149,7 +162,7 @@ compute_uninit_opnds_pos (gimple phi)
{
tree op = gimple_phi_arg_def (phi, i);
if (TREE_CODE (op) == SSA_NAME
&& ssa_undefined_value_p (op)
&& uninit_undefined_value_p (op)
&& !can_skip_redundant_opnd (op, phi))
{
/* Ignore SSA_NAMEs on abnormal edges to setjmp
@ -518,7 +531,7 @@ collect_phi_def_edges (gimple phi, basic_block cd_root,
gimple_bb (def), cd_root))
collect_phi_def_edges (def, cd_root, edges,
visited_phis);
else if (!ssa_undefined_value_p (opnd))
else if (!uninit_undefined_value_p (opnd))
{
if (dump_file && (dump_flags & TDF_DETAILS))
{
@ -2002,7 +2015,7 @@ execute_late_warn_uninitialized (void)
{
tree op = gimple_phi_arg_def (phi, i);
if (TREE_CODE (op) == SSA_NAME
&& ssa_undefined_value_p (op))
&& uninit_undefined_value_p (op))
{
worklist.safe_push (phi);
pointer_set_insert (added_to_worklist, phi);