PR opt/8492

[pf3gnuchains/gcc-fork.git] / gcc / gcse.c

diff --git a/gcc/gcse.c b/gcc/gcse.c
index 2171994..272e39a 100644 (file)
--- a/gcc/gcse.c
+++ b/gcc/gcse.c
@@ -4378,6 +4378,7 @@ local_cprop_pass (alter_jumps)
   rtx insn;
   struct reg_use *reg_used;
   rtx libcall_stack[MAX_NESTED_LIBCALLS + 1], *libcall_sp;
+  bool changed = false;
 
   cselib_init ();
   libcall_sp = &libcall_stack[MAX_NESTED_LIBCALLS];
@@ -4409,13 +4410,19 @@ local_cprop_pass (alter_jumps)
                   reg_used++, reg_use_count--)
                if (do_local_cprop (reg_used->reg_rtx, insn, alter_jumps,
                    libcall_sp))
-                 break;
+                 {
+                   changed = true;
+                   break;
+                 }
            }
          while (reg_use_count);
        }
       cselib_process_insn (insn);
     }
   cselib_finish ();
+  /* Global analysis may get into infinite loops for unreachable blocks.  */
+  if (changed && alter_jumps)
+    delete_unreachable_blocks ();
 }
 
 /* Forward propagate copies.  This includes copies and constants.  Return
@@ -4506,6 +4513,9 @@ one_cprop_pass (pass, cprop_jumps, bypass_jumps)
       fprintf (gcse_file, "%d const props, %d copy props\n\n",
               const_prop_count, copy_prop_count);
     }
+  /* Global analysis may get into infinite loops for unreachable blocks.  */
+  if (changed && cprop_jumps)
+    delete_unreachable_blocks ();
 
   return changed;
 }