1 files changed, 71 insertions, 34 deletions

diff --git a/gcc/tsan.c b/gcc/tsan.c
index 1bc146f..567a421 100644
--- a/gcc/tsan.c
+++ b/gcc/tsan.c
@@ -704,6 +704,47 @@ instrument_gimple (gimple_stmt_iterator *gsi)
   return instrumented;
 }
 
+/* Replace TSAN_FUNC_EXIT internal call with function exit tsan builtin.  */
+
+static void
+replace_func_exit (gimple stmt)
+{
+  tree builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_FUNC_EXIT);
+  gimple g = gimple_build_call (builtin_decl, 0);
+  gimple_set_location (g, cfun->function_end_locus);
+  gimple_stmt_iterator gsi = gsi_for_stmt (stmt);
+  gsi_replace (&gsi, g, true);
+}
+
+/* Instrument function exit.  Used when TSAN_FUNC_EXIT does not exist.  */
+
+static void
+instrument_func_exit (void)
+{
+  location_t loc;
+  basic_block exit_bb;
+  gimple_stmt_iterator gsi;
+  gimple stmt, g;
+  tree builtin_decl;
+  edge e;
+  edge_iterator ei;
+
+  /* Find all function exits.  */
+  exit_bb = EXIT_BLOCK_PTR_FOR_FN (cfun);
+  FOR_EACH_EDGE (e, ei, exit_bb->preds)
+    {
+      gsi = gsi_last_bb (e->src);
+      stmt = gsi_stmt (gsi);
+      gcc_assert (gimple_code (stmt) == GIMPLE_RETURN
+		  || gimple_call_builtin_p (stmt, BUILT_IN_RETURN));
+      loc = gimple_location (stmt);
+      builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_FUNC_EXIT);
+      g = gimple_build_call (builtin_decl, 0);
+      gimple_set_location (g, loc);
+      gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+    }
+}
+
 /* Instruments all interesting memory accesses in the current function.
    Return true if func entry/exit should be instrumented.  */
 
@@ -713,10 +754,38 @@ instrument_memory_accesses (void)
   basic_block bb;
   gimple_stmt_iterator gsi;
   bool fentry_exit_instrument = false;
+  bool func_exit_seen = false;
+  auto_vec<gimple> tsan_func_exits;
 
   FOR_EACH_BB_FN (bb, cfun)
     for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
-      fentry_exit_instrument |= instrument_gimple (&gsi);
+      {
+	gimple stmt = gsi_stmt (gsi);
+	if (is_gimple_call (stmt)
+	    && gimple_call_internal_p (stmt)
+	    && gimple_call_internal_fn (stmt) == IFN_TSAN_FUNC_EXIT)
+	  {
+	    if (fentry_exit_instrument)
+	      replace_func_exit (stmt);
+	    else
+	      tsan_func_exits.safe_push (stmt);
+	    func_exit_seen = true;
+	  }
+	else
+	  fentry_exit_instrument |= instrument_gimple (&gsi);
+      }
+  unsigned int i;
+  gimple stmt;
+  FOR_EACH_VEC_ELT (tsan_func_exits, i, stmt)
+    if (fentry_exit_instrument)
+      replace_func_exit (stmt);
+    else
+      {
+	gsi = gsi_for_stmt (stmt);
+	gsi_remove (&gsi, true);
+      }
+  if (fentry_exit_instrument && !func_exit_seen)
+    instrument_func_exit ();
   return fentry_exit_instrument;
 }
 
@@ -745,35 +814,6 @@ instrument_func_entry (void)
   gsi_insert_seq_on_edge_immediate (e, seq);
 }
 
-/* Instruments function exits.  */
-
-static void
-instrument_func_exit (void)
-{
-  location_t loc;
-  basic_block exit_bb;
-  gimple_stmt_iterator gsi;
-  gimple stmt, g;
-  tree builtin_decl;
-  edge e;
-  edge_iterator ei;
-
-  /* Find all function exits.  */
-  exit_bb = EXIT_BLOCK_PTR_FOR_FN (cfun);
-  FOR_EACH_EDGE (e, ei, exit_bb->preds)
-    {
-      gsi = gsi_last_bb (e->src);
-      stmt = gsi_stmt (gsi);
-      gcc_assert (gimple_code (stmt) == GIMPLE_RETURN
-		  || gimple_call_builtin_p (stmt, BUILT_IN_RETURN));
-      loc = gimple_location (stmt);
-      builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_FUNC_EXIT);
-      g = gimple_build_call (builtin_decl, 0);
-      gimple_set_location (g, loc);
-      gsi_insert_before (&gsi, g, GSI_SAME_STMT);
-    }
-}
-
 /* ThreadSanitizer instrumentation pass.  */
 
 static unsigned
@@ -781,10 +821,7 @@ tsan_pass (void)
 {
   initialize_sanitizer_builtins ();
   if (instrument_memory_accesses ())
-    {
-      instrument_func_entry ();
-      instrument_func_exit ();
-    }
+    instrument_func_entry ();
   return 0;
 }