This was meant only as a TLC, but it also fixes PR59306. Using
walk_gimple_op was an overkill; gimple_{store,assign_load}_p is
enough. As a side effect, it also fixes the bug because now we
better restrict what goes into instrument_member_call.
Bootstrapped, ran ubsan testsuite on x86_64-linux, ok for trunk?
2013-11-27 Marek Polacek <pola...@redhat.com>
PR sanitizer/59306
* ubsan.c (instrument_null): Use gimple_store_p/gimple_assign_load_p
instead of walk_gimple_op.
(ubsan_pass): Adjust. Call instrument_null only if SANITIZE_NULL.
testsuite/
* g++.dg/ubsan/pr59306.C:
--- gcc/ubsan.c.mp3 2013-11-27 09:55:23.573252894 +0100
+++ gcc/ubsan.c 2013-11-27 11:15:29.893507768 +0100
@@ -614,24 +614,22 @@ instrument_mem_ref (tree t, gimple_stmt_
gsi_insert_before (iter, g, GSI_SAME_STMT);
}
-/* Callback function for the pointer instrumentation. */
+/* Perform the pointer instrumentation. */
-static tree
-instrument_null (tree *tp, int * /*walk_subtree*/, void *data)
+static void
+instrument_null (gimple_stmt_iterator gsi, bool is_lhs)
{
- tree t = *tp;
+ gimple stmt = gsi_stmt (gsi);
+ tree t = is_lhs ? gimple_get_lhs (stmt) : gimple_assign_rhs1 (stmt);
+ t = get_base_address (t);
const enum tree_code code = TREE_CODE (t);
- struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
-
if (code == MEM_REF
&& TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME)
- instrument_mem_ref (TREE_OPERAND (t, 0), &wi->gsi, wi->is_lhs);
+ instrument_mem_ref (TREE_OPERAND (t, 0), &gsi, is_lhs);
else if (code == ADDR_EXPR
&& POINTER_TYPE_P (TREE_TYPE (t))
&& TREE_CODE (TREE_TYPE (TREE_TYPE (t))) == METHOD_TYPE)
- instrument_member_call (&wi->gsi);
-
- return NULL_TREE;
+ instrument_member_call (&gsi);
}
/* Gate and execute functions for ubsan pass. */
@@ -646,7 +644,6 @@ ubsan_pass (void)
{
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);)
{
- struct walk_stmt_info wi;
gimple stmt = gsi_stmt (gsi);
if (is_gimple_debug (stmt) || gimple_clobber_p (stmt))
{
@@ -654,9 +651,14 @@ ubsan_pass (void)
continue;
}
- memset (&wi, 0, sizeof (wi));
- wi.gsi = gsi;
- walk_gimple_op (stmt, instrument_null, &wi);
+ if (flag_sanitize & SANITIZE_NULL)
+ {
+ if (gimple_store_p (stmt))
+ instrument_null (gsi, true);
+ if (gimple_assign_load_p (stmt))
+ instrument_null (gsi, false);
+ }
+
gsi_next (&gsi);
}
}
--- gcc/testsuite/g++.dg/ubsan/pr59306.C.mp3 2013-11-27 11:15:17.900456072
+0100
+++ gcc/testsuite/g++.dg/ubsan/pr59306.C 2013-11-27 11:15:01.696387988
+0100
@@ -0,0 +1,14 @@
+// { dg-do compile }
+// { dg-options "-fsanitize=undefined" }
+// { dg-skip-if "" { *-*-* } { "-flto" } { "" } }
+
+class A {
+ void bar (void (A::*) (int));
+ void foo (int);
+ void B ();
+};
+
+void A::B()
+{
+ bar (&A::foo);
+}
Marek
