loop.c

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@31500 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 8 insertions, 4 deletions

diff --git a/gcc/unroll.c b/gcc/unroll.c
index 9225a9c1e9b..b166298653e 100644
--- a/gcc/unroll.c
+++ b/gcc/unroll.c
@@ -3702,10 +3702,14 @@ loop_iterations (loop)
       return 0;
     }
 
-  /* The only new registers that care created before loop iterations are
-     givs made from biv increments, so this should never occur.  */
-
-  if ((unsigned) REGNO (iteration_var) >= reg_iv_type->num_elements)
+  /* The only new registers that are created before loop iterations
+     are givs made from biv increments or registers created by
+     load_mems.  In the latter case, it is possible that try_copy_prop
+     will propagate a new pseudo into the old iteration register but
+     this will be marked by having the REG_USERVAR_P bit set.  */
+
+  if ((unsigned) REGNO (iteration_var) >= reg_iv_type->num_elements
+      && ! REG_USERVAR_P (iteration_var))
     abort ();
 
   iteration_info (iteration_var, &initial_value, &increment,