* flow.c (reorder_basic_blocks): Account for barriers when writing

	over NEXT_INSN (last_bb->end).
	(verify_flow_info): Add check for missing barriers.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@32545 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c139e27..8c5ac0b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+
+2000-03-14  Jason Eckhardt  <jle@cygnus.com>
+       * flow.c (reorder_basic_blocks): Account for barriers when writing
+       over NEXT_INSN (last_bb->end).
+       (verify_flow_info): Add check for missing barriers.
+
 2000-03-14  Greg McGary  <gkm@gnu.org>
 
        * c-lex.h (enum rid): Add RID_BOUNDED & RID_UNBOUNDED.

diff --git a/gcc/flow.c b/gcc/flow.c
index 26c1a6f..fe221ca 100644 (file)
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -5785,6 +5785,7 @@ set_block_num (insn, bb)
      and NOTE_INSN_BASIC_BLOCK
    - check that all insns are in the basic blocks 
    (except the switch handling code, barriers and notes)
+   - check that all returns are followed by barriers
 
    In future it can be extended check a lot of other stuff as well
    (reachability of basic blocks, life information, etc. etc.).  */
@@ -5988,6 +5989,12 @@ verify_flow_info ()
            }
        }
 
+      if (GET_RTX_CLASS (GET_CODE (x)) == 'i'
+         && GET_CODE (x) == JUMP_INSN
+         && returnjump_p (x)
+         && ! (NEXT_INSN (x) && GET_CODE (NEXT_INSN (x)) == BARRIER))
+           fatal_insn ("Return not followed by barrier", x);
+
       x = NEXT_INSN (x);
     }
 
@@ -7758,8 +7765,19 @@ reorder_basic_blocks ()
          BASIC_BLOCK (j) = tempbb;
        }
     }
-      
-  NEXT_INSN (BASIC_BLOCK (n_basic_blocks - 1)->end) = last_insn;
+     
+    {
+      rtx xafter = skip_insns_between_block (BASIC_BLOCK (n_basic_blocks - 1),
+                                            REORDER_SKIP_AFTER);
+      if (xafter)
+       NEXT_INSN (xafter) = last_insn;
+      else
+       abort();
+    }
+
+#ifdef ENABLE_CHECKING
+  verify_flow_info ();
+#endif
 
   for (i = 0; i < n_basic_blocks - 1; i++)
     {