2008-09-18 Andrew Pinski <andrew_pinski@playstation.sony.com>

        PR rtl-opt/37451
        * loop-doloop.c (doloop_modify): New argument zero_extend_p and
        zero extend count after the correction to it is done.
        (doloop_optimize): Update call to doloop_modify, don't zero extend
        count before call.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@140470 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 11 insertions, 5 deletions

diff --git a/gcc/loop-doloop.c b/gcc/loop-doloop.c
index a039f367925..25369dd4a4d 100644
--- a/gcc/loop-doloop.c
+++ b/gcc/loop-doloop.c
@@ -333,11 +333,13 @@ add_test (rtx cond, edge *e, basic_block dest)
    describes the loop, DESC describes the number of iterations of the
    loop, and DOLOOP_INSN is the low-overhead looping insn to emit at the
    end of the loop.  CONDITION is the condition separated from the
-   DOLOOP_SEQ.  COUNT is the number of iterations of the LOOP.  */
+   DOLOOP_SEQ.  COUNT is the number of iterations of the LOOP.
+   ZERO_EXTEND_P says to zero extend COUNT after the increment of it to
+   word_mode.  */
 
 static void
 doloop_modify (struct loop *loop, struct niter_desc *desc,
-	       rtx doloop_seq, rtx condition, rtx count)
+	       rtx doloop_seq, rtx condition, rtx count, bool zero_extend_p)
 {
   rtx counter_reg;
   rtx tmp, noloop = NULL_RTX;
@@ -413,6 +415,10 @@ doloop_modify (struct loop *loop, struct niter_desc *desc,
   if (increment_count)
     count = simplify_gen_binary (PLUS, mode, count, const1_rtx);
 
+  if (zero_extend_p)
+    count = simplify_gen_unary (ZERO_EXTEND, word_mode,
+				count, mode);
+
   /* Insert initialization of the count register into the loop header.  */
   start_sequence ();
   tmp = force_operand (count, counter_reg);
@@ -547,6 +553,7 @@ doloop_optimize (struct loop *loop)
   struct niter_desc *desc;
   unsigned word_mode_size;
   unsigned HOST_WIDE_INT word_mode_max;
+  bool zero_extend_p = false;
 
   if (dump_file)
     fprintf (dump_file, "Doloop: Processing loop %d.\n", loop->num);
@@ -621,8 +628,7 @@ doloop_optimize (struct loop *loop)
     {
       if (word_mode_size > GET_MODE_BITSIZE (mode))
 	{
-	  count = simplify_gen_unary (ZERO_EXTEND, word_mode,
-				      count, mode);
+	  zero_extend_p = true;
 	  iterations = simplify_gen_unary (ZERO_EXTEND, word_mode,
 					   iterations, mode);
 	  iterations_max = simplify_gen_unary (ZERO_EXTEND, word_mode,
@@ -666,7 +672,7 @@ doloop_optimize (struct loop *loop)
       return false;
     }
 
-  doloop_modify (loop, desc, doloop_seq, condition, count);
+  doloop_modify (loop, desc, doloop_seq, condition, count, zero_extend_p);
   return true;
 }