asan: Fix ICE during instrumentation of returns_twice calls [PR112709]

The following patch on top of the previously posted ubsan/gimple-iterator
one handles asan the same.  While the case of returning by hidden reference
is handled differently because of the first recently posted asan patch,
this deals with instrumentation of the aggregates returned in registers
case as well as instrumentation of loads from aggregate memory in the
function arguments of returns_twice calls.

2024-03-13  Jakub Jelinek  <jakub@redhat.com>

	PR sanitizer/112709
	* asan.cc (maybe_create_ssa_name, maybe_cast_to_ptrmode,
	build_check_stmt, maybe_instrument_call, asan_expand_mark_ifn): Use
	gsi_safe_insert_before instead of gsi_insert_before.

	* gcc.dg/asan/pr112709-2.c: New test.

(cherry picked from commit 6586359e8e4c611dd96129b5d4f24023949ac3fc)

diff --git a/gcc/asan.cc b/gcc/asan.cc
index 8d0ffb497cc905c69feedc201ae3105e9d95d990..15feecfb495d3c91b8ae8acc849e0b829659d0a2 100644 (file)
--- a/gcc/asan.cc
+++ b/gcc/asan.cc
@@ -2571,7 +2571,7 @@ maybe_create_ssa_name (location_t loc, tree base, gimple_stmt_iterator *iter,
   gimple *g = gimple_build_assign (make_ssa_name (TREE_TYPE (base)), base);
   gimple_set_location (g, loc);
   if (before_p)
-    gsi_insert_before (iter, g, GSI_SAME_STMT);
+    gsi_safe_insert_before (iter, g);
   else
     gsi_insert_after (iter, g, GSI_NEW_STMT);
   return gimple_assign_lhs (g);
@@ -2590,7 +2590,7 @@ maybe_cast_to_ptrmode (location_t loc, tree len, gimple_stmt_iterator *iter,
                                  NOP_EXPR, len);
   gimple_set_location (g, loc);
   if (before_p)
-    gsi_insert_before (iter, g, GSI_SAME_STMT);
+    gsi_safe_insert_before (iter, g);
   else
     gsi_insert_after (iter, g, GSI_NEW_STMT);
   return gimple_assign_lhs (g);
@@ -2681,7 +2681,7 @@ build_check_stmt (location_t loc, tree base, tree len,
                                                 align / BITS_PER_UNIT));
   gimple_set_location (g, loc);
   if (before_p)
-    gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+    gsi_safe_insert_before (&gsi, g);
   else
     {
       gsi_insert_after (&gsi, g, GSI_NEW_STMT);
@@ -3020,7 +3020,7 @@ maybe_instrument_call (gimple_stmt_iterator *iter)
          tree decl = builtin_decl_implicit (BUILT_IN_ASAN_HANDLE_NO_RETURN);
          gimple *g = gimple_build_call (decl, 0);
          gimple_set_location (g, gimple_location (stmt));
-         gsi_insert_before (iter, g, GSI_SAME_STMT);
+         gsi_safe_insert_before (iter, g);
        }
     }
 
@@ -3844,7 +3844,7 @@ asan_expand_mark_ifn (gimple_stmt_iterator *iter)
       g = gimple_build_assign (make_ssa_name (pointer_sized_int_node),
                               NOP_EXPR, len);
       gimple_set_location (g, loc);
-      gsi_insert_before (iter, g, GSI_SAME_STMT);
+      gsi_safe_insert_before (iter, g);
       tree sz_arg = gimple_assign_lhs (g);
 
       tree fun

diff --git a/gcc/testsuite/gcc.dg/asan/pr112709-2.c b/gcc/testsuite/gcc.dg/asan/pr112709-2.c
new file mode 100644 (file)
index 0000000..e793f53
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/asan/pr112709-2.c
@@ -0,0 +1,50 @@
+/* PR sanitizer/112709 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=address -O2" } */
+
+struct S { char c[1024]; } *p;
+int foo (int);
+
+__attribute__((returns_twice, noipa)) int
+bar (struct S x)
+{
+  (void) x.c[0];
+  return 0;
+}
+
+void
+baz (int *y)
+{
+  foo (1);
+  *y = bar (*p);
+}
+
+void
+qux (int x, int *y)
+{
+  if (x == 25)
+    x = foo (2);
+  else if (x == 42)
+    x = foo (foo (3));
+  *y = bar (*p);
+}
+
+void
+corge (int x, int *y)
+{
+  void *q[] = { &&l1, &&l2, &&l3, &&l3 };
+  if (x == 25)
+    {
+    l1:
+      x = foo (2);
+    }
+  else if (x == 42)
+    {
+    l2:
+      x = foo (foo (3));
+    }
+l3:
+  *y = bar (*p);
+  if (x < 4)
+    goto *q[x & 3];
+}