[MIPS] RFA: Use new rtl iterators in mips_need_noat_wrapper_p

[Richard Sandiford]

This is part of a series to remove uses of for_each_rtx from the ports.

Tested by making sure there were no code changes for gcc.dg, gcc.c-torture
and g++.dg for mips64-elf.  OK to install?

Thanks,
Richard


gcc/
        * config/mips/mips.c (mips_at_reg_p): Delete.
        (mips_need_noat_wrapper_p): Use FOR_EACH_SUBRTX.

Index: gcc/config/mips/mips.c
===================================================================
--- gcc/config/mips/mips.c      2014-10-25 09:51:21.912852052 +0100
+++ gcc/config/mips/mips.c      2014-10-25 09:51:22.291855430 +0100
@@ -17528,26 +17528,20 @@ mips_epilogue_uses (unsigned int regno)
   return false;
 }
 
-/* A for_each_rtx callback.  Stop the search if *X is an AT register.  */
-
-static int
-mips_at_reg_p (rtx *x, void *data ATTRIBUTE_UNUSED)
-{
-  return REG_P (*x) && REGNO (*x) == AT_REGNUM;
-}
-
 /* Return true if INSN needs to be wrapped in ".set noat".
    INSN has NOPERANDS operands, stored in OPVEC.  */
 
 static bool
 mips_need_noat_wrapper_p (rtx_insn *insn, rtx *opvec, int noperands)
 {
-  int i;
-
   if (recog_memoized (insn) >= 0)
-    for (i = 0; i < noperands; i++)
-      if (for_each_rtx (&opvec[i], mips_at_reg_p, NULL))
-       return true;
+    {
+      subrtx_iterator::array_type array;
+      for (int i = 0; i < noperands; i++)
+       FOR_EACH_SUBRTX (iter, array, opvec[i], NONCONST)
+         if (REG_P (*iter) && REGNO (*iter) == AT_REGNUM)
+           return true;
+    }
   return false;
 }