[PATCH] Fix PR49615

[Richard Guenther]

This fixes an oversight in split_bbs_on_noreturn_calls.

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied everywhere.

Richard.

2011-07-04  Richard Guenther  <rguent...@suse.de>

        PR tree-optimization/49615
        * tree-cfgcleanup.c (split_bbs_on_noreturn_calls): Fix
        basic-block index check.

        * g++.dg/torture/pr49615.C: New testcase.

Index: gcc/tree-cfgcleanup.c
===================================================================
*** gcc/tree-cfgcleanup.c       (revision 175752)
--- gcc/tree-cfgcleanup.c       (working copy)
*************** split_bbs_on_noreturn_calls (void)
*** 599,605 ****
           BB is present in the cfg.  */
        if (bb == NULL
            || bb->index < NUM_FIXED_BLOCKS
!           || bb->index >= n_basic_blocks
            || BASIC_BLOCK (bb->index) != bb
            || !gimple_call_noreturn_p (stmt))
          continue;
--- 599,605 ----
           BB is present in the cfg.  */
        if (bb == NULL
            || bb->index < NUM_FIXED_BLOCKS
!           || bb->index >= last_basic_block
            || BASIC_BLOCK (bb->index) != bb
            || !gimple_call_noreturn_p (stmt))
          continue;
Index: gcc/testsuite/g++.dg/torture/pr49615.C
===================================================================
*** gcc/testsuite/g++.dg/torture/pr49615.C      (revision 0)
--- gcc/testsuite/g++.dg/torture/pr49615.C      (revision 0)
***************
*** 0 ****
--- 1,29 ----
+ /* { dg-do compile } */
+ /* { dg-options "-g" } */
+ 
+ template <class T>
+ static inline bool Dispatch (T* obj, void (T::*func) ())
+ {
+   (obj->*func) ();
+ }
+ class C
+ {
+   bool f (int);
+   void g ();
+ };
+ bool C::f (int n)
+ {
+   bool b;
+   switch (n)
+     {
+       case 0:
+         b = Dispatch (this, &C::g);
+       case 1:
+         b = Dispatch (this, &C::g);
+     }
+ }
+ void C::g ()
+ {
+   for (;;) { }
+ }
+