[PATCH] Don't consider clones of user functions as uninstrumentable by mudflap (PR libmudflap/40778)

[Jakub Jelinek]

Hi!

It isn't clear why mudflap doesn't instrument DECL_ARTIFICIAL functions,
if it couldn't avoid instrumenting just a subset of them.
But there is certainly no reason why it shouldn't instrument normal clones
of user functions (OpenMP, TM, ISRA, ...).  Fixed thusly,
bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2012-01-19  Jakub Jelinek  <ja...@redhat.com>

        PR libmudflap/40778
        * tree-mudflap.c (mf_artificial): New function.
        (execute_mudflap_function_ops, execute_mudflap_function_decls,
        mx_register_decls, mudflap_enqueue_decl): Use it.

        * testsuite/libmudflap.c/fail68-frag.c: New test.

--- gcc/tree-mudflap.c  2011-12-08 16:36:52.233959103 +0100
+++ gcc/tree-mudflap.c  2012-01-19 11:18:45.817151412 +0100
@@ -69,6 +69,13 @@ static tree mx_xfn_xform_decls (gimple_s
 static gimple_seq mx_register_decls (tree, gimple_seq, location_t);
 static unsigned int execute_mudflap_function_decls (void);
 
+/* Return true if DECL is artificial stub that shouldn't be instrumented by
+   mf.  We should instrument clones of non-artificial functions.  */
+static inline bool
+mf_artificial (const_tree decl)
+{
+  return DECL_ARTIFICIAL (DECL_ORIGIN (decl));
+}
 
 /* ------------------------------------------------------------------------ */
 /* Some generally helpful functions for mudflap instrumentation.  */
@@ -412,8 +419,8 @@ execute_mudflap_function_ops (void)
 
   /* Don't instrument functions such as the synthetic constructor
      built during mudflap_finish_file.  */
-  if (mf_marked_p (current_function_decl) ||
-      DECL_ARTIFICIAL (current_function_decl))
+  if (mf_marked_p (current_function_decl)
+      || mf_artificial (current_function_decl))
     return 0;
 
   push_gimplify_context (&gctx);
@@ -994,8 +1001,8 @@ execute_mudflap_function_decls (void)
 
   /* Don't instrument functions such as the synthetic constructor
      built during mudflap_finish_file.  */
-  if (mf_marked_p (current_function_decl) ||
-      DECL_ARTIFICIAL (current_function_decl))
+  if (mf_marked_p (current_function_decl)
+      || mf_artificial (current_function_decl))
     return 0;
 
   push_gimplify_context (&gctx);
@@ -1078,7 +1085,7 @@ mx_register_decls (tree decl, gimple_seq
           /* Add the __mf_register call at the current appending point.  */
           if (gsi_end_p (initially_stmts))
            {
-             if (!DECL_ARTIFICIAL (decl))
+             if (!mf_artificial (decl))
                warning (OPT_Wmudflap,
                         "mudflap cannot track %qE in stub function",
                         DECL_NAME (decl));
@@ -1249,7 +1256,7 @@ mudflap_enqueue_decl (tree obj)
      during mudflap_finish_file ().  That would confuse the user,
      since the text would refer to variables that don't show up in the
      user's source code.  */
-  if (DECL_P (obj) && DECL_EXTERNAL (obj) && DECL_ARTIFICIAL (obj))
+  if (DECL_P (obj) && DECL_EXTERNAL (obj) && mf_artificial (obj))
     return;
 
   VEC_safe_push (tree, gc, deferred_static_decls, obj);
--- libmudflap/testsuite/libmudflap.c/fail68-frag.c.jj  2010-12-16 
17:15:40.000000000 +0100
+++ libmudflap/testsuite/libmudflap.c/fail68-frag.c     2010-12-16 
17:26:16.000000000 +0100
@@ -0,0 +1,27 @@
+/* PR libmudflap/40778 */
+
+char p[32];
+static int j;
+
+__attribute__((noinline))
+static void foo (int i)
+{
+  if (j++ == 0)
+    p[i + 4] = 12;
+  else
+    p[i - 4] = 13;
+}
+
+int
+main ()
+{
+  foo (30);
+  foo (30);
+  foo (30);
+  return 0;
+}
+
+/* { dg-output "mudflap violation 1.*" } */
+/* { dg-output "Nearby object 1.*" } */
+/* { dg-output "mudflap object.*name.*p" } */
+/* { dg-do run { xfail *-*-* } } */

        Jakub