[gcc r14-9445] asan: Fix ICE during instrumentation of returns_twice calls [PR112709]

[gcc r14-9445] asan: Fix ICE during instrumentation of returns_twice calls [PR112709]

[Jakub Jelinek]

https://gcc.gnu.org/g:6586359e8e4c611dd96129b5d4f24023949ac3fc

commit r14-9445-g6586359e8e4c611dd96129b5d4f24023949ac3fc
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Wed Mar 13 09:19:05 2024 +0100

    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.

Diff:
---
 gcc/asan.cc                            | 10 +++----
 gcc/testsuite/gcc.dg/asan/pr112709-2.c | 50 ++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/gcc/asan.cc b/gcc/asan.cc
index c533b09b1a1..cfe83106460 100644
--- a/gcc/asan.cc
+++ b/gcc/asan.cc
@@ -2574,7 +2574,7 @@ 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);
@@ -2593,7 +2593,7 @@ 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);
@@ -2684,7 +2684,7 @@ 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);
@@ -3025,7 +3025,7 @@ 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);
 	}
     }
 
@@ -3852,7 +3852,7 @@ 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
index 00000000000..e793f53507f
--- /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];
+}