[PATCH, loop2_invariant] Skip inv (marked as move) from depends_on

[Zhenqiang Chen]

Hi,

The patch skips an invariant from depends_on if it has been marked as
"move" since its register pressure and cost had been taken into
account in previous iterations.

Bootstrap and no make check regression on X86-64.
Bootstrap and no make check regression on X86-64 with
flag_ira_loop_pressure = true.

OK for trunk?

Thanks!
-Zhenqiang

ChangeLog:
2014-06-10  Zhenqiang Chen  <zhenqiang.c...@linaro.org>

        * loop-invariant.c (get_inv_cost): Skip invariants, which are marked
        as "move", from depends_on.

diff --git a/gcc/loop-invariant.c b/gcc/loop-invariant.c
index e822bb6..fca9c2f 100644
--- a/gcc/loop-invariant.c
+++ b/gcc/loop-invariant.c
@@ -1148,6 +1148,10 @@ get_inv_cost (struct invariant *inv, int
*comp_cost, unsigned *regs_needed,

       dep = invariants[depno];

+      /* If DEP is moved out of the loop, it is not a depends_on any more.  */
+      if (dep->move)
+       continue;
+
       dep_ret = get_inv_cost (dep, &acomp_cost, aregs_needed, &dep_cl);

       if (! flag_ira_loop_pressure)