Avoid reversing bivs with maybe_multiple set.

From-SVN: r30929

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7a23bb1c6f6a01b8d1bf35048f622cecbb70de4c..01016d13e190fd8656fec67e2687cd6d5409fe25 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+1999-12-14  Bernd Schmidt  <bernds@cygnus.co.uk>
+
+       * loop.c (check_dbra_loop): Can't reverse a biv that has
+       maybe_multiple set.
+
 1999-12-14  Nick Clifton  <nickc@cygnus.com>
 
        * config/arm/arm.c: Add support for -mcpu=arm720 command line

diff --git a/gcc/loop.c b/gcc/loop.c
index 9d55f815281efdc52405b590d853b2151184ab3b..573a76aad6a3bdf03a438d6d581e0fedeb5e8f96 100644 (file)
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -7953,6 +7953,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info)
   for (bl = loop_iv_list; bl; bl = bl->next)
     {
       if (bl->biv_count == 1
+         && ! bl->biv->maybe_multiple
          && bl->biv->dest_reg == XEXP (comparison, 0)
          && ! reg_used_between_p (regno_reg_rtx[bl->regno], bl->biv->insn,
                                   first_compare))