flag-types.h (enum sanitize_code): Add SANITIZE_NONNULL_ATTRIBUTE and SANITIZE_RETURNS_NONNULL_ATTRIBUTE...

gcc/
	* flag-types.h (enum sanitize_code): Add SANITIZE_NONNULL_ATTRIBUTE
	and SANITIZE_RETURNS_NONNULL_ATTRIBUTE, or them into SANITIZE_UNDEFINED.
	* opts.c (common_handle_option): Handle SANITIZE_NONNULL_ATTRIBUTE and
	SANITIZE_RETURNS_NONNULL_ATTRIBUTE and disable
	flag_delete_null_pointer_checks for them.
	* sanitizer.def (BUILT_IN_UBSAN_HANDLE_NONNULL_ARG,
	BUILT_IN_UBSAN_HANDLE_NONNULL_ARG_ABORT,
	BUILT_IN_UBSAN_HANDLE_NONNULL_RETURN,
	BUILT_IN_UBSAN_HANDLE_NONNULL_RETURN_ABORT): New.
	* ubsan.c (instrument_bool_enum_load): Set *gsi back to
	stmt's iterator.
	(instrument_nonnull_arg, instrument_nonnull_return): New functions.
	(pass_ubsan::gate): Return true even for SANITIZE_NONNULL_ATTRIBUTE
	or SANITIZE_RETURNS_NONNULL_ATTRIBUTE.
	(pass_ubsan::execute): Call instrument_nonnull_{arg,return}.
	* doc/invoke.texi (-fsanitize=nonnull-attribute,
	-fsanitize=returns-nonnull-attribute): Document.
gcc/testsuite/
	* c-c++-common/ubsan/attrib-3.c: New test.
	* c-c++-common/ubsan/nonnull-1.c: New test.
	* c-c++-common/ubsan/nonnull-2.c: New test.
	* c-c++-common/ubsan/nonnull-3.c: New test.
	* c-c++-common/ubsan/nonnull-4.c: New test.
	* c-c++-common/ubsan/nonnull-5.c: New test.
libsanitizer/
	* ubsan/ubsan_handlers.cc, ubsan/ubsan_handlers.h: Cherry pick
	upstream r215485, r217389, r217391 and r217400.

From-SVN: r215118

1 files changed, 139 insertions, 2 deletions

diff --git a/gcc/ubsan.c b/gcc/ubsan.c
index 745ca80..e3128ad 100644
--- a/gcc/ubsan.c
+++ b/gcc/ubsan.c
@@ -1090,6 +1090,7 @@ instrument_bool_enum_load (gimple_stmt_iterator *gsi)
     }
   gimple_set_location (g, loc);
   gsi_insert_before (&gsi2, g, GSI_SAME_STMT);
+  *gsi = gsi_for_stmt (stmt);
 }
 
 /* Instrument float point-to-integer conversion.  TYPE is an integer type of
@@ -1215,6 +1216,122 @@ ubsan_instrument_float_cast (location_t loc, tree type, tree expr)
 		      fn, integer_zero_node);
 }
 
+/* Instrument values passed to function arguments with nonnull attribute.  */
+
+static void
+instrument_nonnull_arg (gimple_stmt_iterator *gsi)
+{
+  gimple stmt = gsi_stmt (*gsi);
+  location_t loc[2];
+  /* infer_nonnull_range needs flag_delete_null_pointer_checks set,
+     while for nonnull sanitization it is clear.  */
+  int save_flag_delete_null_pointer_checks = flag_delete_null_pointer_checks;
+  flag_delete_null_pointer_checks = 1;
+  loc[0] = gimple_location (stmt);
+  loc[1] = UNKNOWN_LOCATION;
+  for (unsigned int i = 0; i < gimple_call_num_args (stmt); i++)
+    {
+      tree arg = gimple_call_arg (stmt, i);
+      if (POINTER_TYPE_P (TREE_TYPE (arg))
+	  && infer_nonnull_range (stmt, arg, false, true))
+	{
+	  gimple g;
+	  if (!is_gimple_val (arg))
+	    {
+	      g = gimple_build_assign (make_ssa_name (TREE_TYPE (arg), NULL),
+				       arg);
+	      gimple_set_location (g, loc[0]);
+	      gsi_insert_before (gsi, g, GSI_SAME_STMT);
+	      arg = gimple_assign_lhs (g);
+	    }
+
+	  basic_block then_bb, fallthru_bb;
+	  *gsi = create_cond_insert_point (gsi, true, false, true,
+					   &then_bb, &fallthru_bb);
+	  g = gimple_build_cond (EQ_EXPR, arg,
+				 build_zero_cst (TREE_TYPE (arg)),
+				 NULL_TREE, NULL_TREE);
+	  gimple_set_location (g, loc[0]);
+	  gsi_insert_after (gsi, g, GSI_NEW_STMT);
+
+	  *gsi = gsi_after_labels (then_bb);
+	  if (flag_sanitize_undefined_trap_on_error)
+	    g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
+	  else
+	    {
+	      tree data = ubsan_create_data ("__ubsan_nonnull_arg_data",
+					     2, loc, NULL_TREE,
+					     build_int_cst (integer_type_node,
+							    i + 1),
+					     NULL_TREE);
+	      data = build_fold_addr_expr_loc (loc[0], data);
+	      enum built_in_function bcode
+		= flag_sanitize_recover
+		  ? BUILT_IN_UBSAN_HANDLE_NONNULL_ARG
+		  : BUILT_IN_UBSAN_HANDLE_NONNULL_ARG_ABORT;
+	      tree fn = builtin_decl_explicit (bcode);
+
+	      g = gimple_build_call (fn, 1, data);
+	    }
+	  gimple_set_location (g, loc[0]);
+	  gsi_insert_before (gsi, g, GSI_SAME_STMT);
+	}
+      *gsi = gsi_for_stmt (stmt);
+    }
+  flag_delete_null_pointer_checks = save_flag_delete_null_pointer_checks;
+}
+
+/* Instrument returns in functions with returns_nonnull attribute.  */
+
+static void
+instrument_nonnull_return (gimple_stmt_iterator *gsi)
+{
+  gimple stmt = gsi_stmt (*gsi);
+  location_t loc[2];
+  tree arg = gimple_return_retval (stmt);
+  /* infer_nonnull_range needs flag_delete_null_pointer_checks set,
+     while for nonnull return sanitization it is clear.  */
+  int save_flag_delete_null_pointer_checks = flag_delete_null_pointer_checks;
+  flag_delete_null_pointer_checks = 1;
+  loc[0] = gimple_location (stmt);
+  loc[1] = UNKNOWN_LOCATION;
+  if (arg
+      && POINTER_TYPE_P (TREE_TYPE (arg))
+      && is_gimple_val (arg)
+      && infer_nonnull_range (stmt, arg, false, true))
+    {
+      basic_block then_bb, fallthru_bb;
+      *gsi = create_cond_insert_point (gsi, true, false, true,
+				       &then_bb, &fallthru_bb);
+      gimple g = gimple_build_cond (EQ_EXPR, arg,
+				    build_zero_cst (TREE_TYPE (arg)),
+				    NULL_TREE, NULL_TREE);
+      gimple_set_location (g, loc[0]);
+      gsi_insert_after (gsi, g, GSI_NEW_STMT);
+
+      *gsi = gsi_after_labels (then_bb);
+      if (flag_sanitize_undefined_trap_on_error)
+	g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
+      else
+	{
+	  tree data = ubsan_create_data ("__ubsan_nonnull_return_data",
+					 2, loc, NULL_TREE, NULL_TREE);
+	  data = build_fold_addr_expr_loc (loc[0], data);
+	  enum built_in_function bcode
+	    = flag_sanitize_recover
+	      ? BUILT_IN_UBSAN_HANDLE_NONNULL_RETURN
+	      : BUILT_IN_UBSAN_HANDLE_NONNULL_RETURN_ABORT;
+	  tree fn = builtin_decl_explicit (bcode);
+
+	  g = gimple_build_call (fn, 1, data);
+	}
+      gimple_set_location (g, loc[0]);
+      gsi_insert_before (gsi, g, GSI_SAME_STMT);
+      *gsi = gsi_for_stmt (stmt);
+    }
+  flag_delete_null_pointer_checks = save_flag_delete_null_pointer_checks;
+}
+
 namespace {
 
 const pass_data pass_data_ubsan =
@@ -1242,7 +1359,9 @@ public:
     {
       return flag_sanitize & (SANITIZE_NULL | SANITIZE_SI_OVERFLOW
 			      | SANITIZE_BOOL | SANITIZE_ENUM
-			      | SANITIZE_ALIGNMENT)
+			      | SANITIZE_ALIGNMENT
+			      | SANITIZE_NONNULL_ATTRIBUTE
+			      | SANITIZE_RETURNS_NONNULL_ATTRIBUTE)
 	     && current_function_decl != NULL_TREE
 	     && !lookup_attribute ("no_sanitize_undefined",
 				   DECL_ATTRIBUTES (current_function_decl));
@@ -1285,7 +1404,25 @@ pass_ubsan::execute (function *fun)
 
 	  if (flag_sanitize & (SANITIZE_BOOL | SANITIZE_ENUM)
 	      && gimple_assign_load_p (stmt))
-	    instrument_bool_enum_load (&gsi);
+	    {
+	      instrument_bool_enum_load (&gsi);
+	      bb = gimple_bb (stmt);
+	    }
+
+	  if ((flag_sanitize & SANITIZE_NONNULL_ATTRIBUTE)
+	      && is_gimple_call (stmt)
+	      && !gimple_call_internal_p (stmt))
+	    {
+	      instrument_nonnull_arg (&gsi);
+	      bb = gimple_bb (stmt);
+	    }
+
+	  if ((flag_sanitize & SANITIZE_RETURNS_NONNULL_ATTRIBUTE)
+	      && gimple_code (stmt) == GIMPLE_RETURN)
+	    {
+	      instrument_nonnull_return (&gsi);
+	      bb = gimple_bb (stmt);
+	    }
 
 	  gsi_next (&gsi);
 	}