[PATCH] Fix ubsan non-call-exceptions ICE (PR tree-optimization/65984)

[Jakub Jelinek]

Hi!

The code I've added in r217755 was assuming that stmt_could_throw_p
memory read will always end a bb, but that is clearly not the case.
Thus, the following patch uses stmt_ends_bb_p instead.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk/5?

2015-05-04  Jakub Jelinek  <ja...@redhat.com>

        PR tree-optimization/65984
        * ubsan.c: Include tree-cfg.h.
        (instrument_bool_enum_load): Use stmt_ends_bb_p instead of
        stmt_could_throw_p test, rename can_throw variable to ends_bb.

        * c-c++-common/ubsan/pr65984.c: New test.

--- gcc/ubsan.c.jj      2015-04-09 21:49:59.000000000 +0200
+++ gcc/ubsan.c 2015-05-04 17:17:34.273661884 +0200
@@ -87,6 +87,7 @@ along with GCC; see the file COPYING3.
 #include "builtins.h"
 #include "tree-object-size.h"
 #include "tree-eh.h"
+#include "tree-cfg.h"
 
 /* Map from a tree to a VAR_DECL tree.  */
 
@@ -1420,7 +1421,7 @@ instrument_bool_enum_load (gimple_stmt_i
       || TREE_CODE (gimple_assign_lhs (stmt)) != SSA_NAME)
     return;
 
-  bool can_throw = stmt_could_throw_p (stmt);
+  bool ends_bb = stmt_ends_bb_p (stmt);
   location_t loc = gimple_location (stmt);
   tree lhs = gimple_assign_lhs (stmt);
   tree ptype = build_pointer_type (TREE_TYPE (rhs));
@@ -1432,7 +1433,7 @@ instrument_bool_enum_load (gimple_stmt_i
   tree mem = build2 (MEM_REF, utype, gimple_assign_lhs (g),
                     build_int_cst (atype, 0));
   tree urhs = make_ssa_name (utype);
-  if (can_throw)
+  if (ends_bb)
     {
       gimple_assign_set_lhs (stmt, urhs);
       g = gimple_build_assign (lhs, NOP_EXPR, urhs);
@@ -1469,7 +1470,7 @@ instrument_bool_enum_load (gimple_stmt_i
   gimple_set_location (g, loc);
   gsi_insert_after (gsi, g, GSI_NEW_STMT);
 
-  if (!can_throw)
+  if (!ends_bb)
     {
       gimple_assign_set_rhs_with_ops (&gsi2, NOP_EXPR, urhs);
       update_stmt (stmt);
--- gcc/testsuite/c-c++-common/ubsan/pr65984.c.jj       2015-05-04 
14:16:59.655378975 +0200
+++ gcc/testsuite/c-c++-common/ubsan/pr65984.c  2015-05-04 17:19:55.875447821 
+0200
@@ -0,0 +1,23 @@
+/* PR tree-optimization/65984 */
+/* { dg-do compile } */
+/* { dg-options "-fnon-call-exceptions -fsanitize=bool,enum" } */
+
+#ifndef __cplusplus
+#define bool _Bool
+#endif
+
+enum E { E0, E1, E2 };
+enum E e[2];
+bool *b;
+
+int
+foo (int i)
+{
+  return e[i];
+}
+
+int
+bar (int i)
+{
+  return b[i];
+}

        Jakub