(copy_loop_body): When check for shared address givs, use new same_insn field.

(copy_loop_body): When check for shared address givs, use
new same_insn field.
(find_splittable_givs): New variable v2.  Scan givs to set new
same_insn field.  Use same_insn to indentify address givs to be
shared.

From-SVN: r8786

diff --git a/gcc/unroll.c b/gcc/unroll.c
index 787bda8..784e09a 100644 (file)
--- a/gcc/unroll.c
+++ b/gcc/unroll.c
@@ -1547,8 +1547,7 @@ copy_loop_body (copy_start, copy_end, map, exit_label, last_iteration,
                        /* Check for shared address givs, and avoid
                           incrementing the shared psuedo reg more than
                           once.  */
-                       if (! (tv != v && tv->insn == v->insn
-                              && tv->new_reg == v->new_reg))
+                       if (! tv->same_insn)
                          {
                            /* tv->dest_reg may actually be a (PLUS (REG)
                               (CONST)) here, so we must call plus_constant
@@ -2449,11 +2448,19 @@ find_splittable_givs (bl, unroll_type, loop_start, loop_end, increment,
      rtx increment;
      int unroll_number;
 {
-  struct induction *v;
+  struct induction *v, *v2;
   rtx final_value;
   rtx tem;
   int result = 0;
 
+  /* Scan the list of givs, and set the same_insn field when there are
+     multiple identical givs in the same insn.  */
+  for (v = bl->giv; v; v = v->next_iv)
+    for (v2 = v->next_iv; v2; v2 = v2->next_iv)
+      if (v->insn == v2->insn && rtx_equal_p (v->new_reg, v2->new_reg)
+         && ! v2->same_insn)
+       v2->same_insn = v;
+
   for (v = bl->giv; v; v = v->next_iv)
     {
       rtx giv_inc, value;
@@ -2629,14 +2636,13 @@ find_splittable_givs (bl, unroll_type, loop_start, loop_end, increment,
 
              v->const_adjust = 0;
 
-             if (v->same && v->same->insn == v->insn
-                 && v->new_reg == v->same->new_reg)
+             if (v->same_insn)
                {
-                 v->dest_reg = v->same->dest_reg;
+                 v->dest_reg = v->same_insn->dest_reg;
                  if (loop_dump_stream)
                    fprintf (loop_dump_stream,
-                            "Sharing address givs with reg %d\n",
-                            REGNO (v->dest_reg));
+                            "Sharing address givs in insn %d\n",
+                            INSN_UID (v->insn));
                }
              else if (unroll_type != UNROLL_COMPLETELY)
                {