2009-02-27 Sebastian Pop <sebastian.pop@amd.com>

[pf3gnuchains/gcc-fork.git] / gcc / loop-doloop.c

diff --git a/gcc/loop-doloop.c b/gcc/loop-doloop.c
index 293b3ae..1f5856f 100644 (file)
--- a/gcc/loop-doloop.c
+++ b/gcc/loop-doloop.c
@@ -333,11 +333,14 @@ 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 from FROM_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, enum machine_mode from_mode)
 {
   rtx counter_reg;
   rtx tmp, noloop = NULL_RTX;
@@ -411,7 +414,11 @@ doloop_modify (struct loop *loop, struct niter_desc *desc,
     }
 
   if (increment_count)
-    count = simplify_gen_binary (PLUS, mode, count, const1_rtx);
+    count = simplify_gen_binary (PLUS, from_mode, count, const1_rtx);
+
+  if (zero_extend_p)
+    count = simplify_gen_unary (ZERO_EXTEND, word_mode,
+                               count, from_mode);
 
   /* Insert initialization of the count register into the loop header.  */
   start_sequence ();
@@ -547,6 +554,7 @@ 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);
@@ -586,7 +594,8 @@ doloop_optimize (struct loop *loop)
 
   max_cost
     = COSTS_N_INSNS (PARAM_VALUE (PARAM_MAX_ITERATIONS_COMPUTATION_COST));
-  if (rtx_cost (desc->niter_expr, SET) > max_cost)
+  if (rtx_cost (desc->niter_expr, SET, optimize_loop_for_speed_p (loop))
+      > max_cost)
     {
       if (dump_file)
        fprintf (dump_file,
@@ -620,8 +629,7 @@ 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,
@@ -665,7 +673,8 @@ 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, mode);
   return true;
 }