Add -std=c99 to avx-cmpsd-1.c and avx-cmpss-1.c.

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

diff --git a/gcc/loop-iv.c b/gcc/loop-iv.c
index 3723dbd..16e9a52 100644 (file)
--- a/gcc/loop-iv.c
+++ b/gcc/loop-iv.c
@@ -1,18 +1,19 @@
 /* Rtl-level induction variable analysis.
 /* Rtl-level induction variable analysis.

-   Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
-   
+   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009
+   Free Software Foundation, Inc.
+

 This file is part of GCC.
 This file is part of GCC.

-   
+

 GCC is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
 Free Software Foundation; either version 3, or (at your option) any
 later version.
 GCC is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
 Free Software Foundation; either version 3, or (at your option) any
 later version.

-   
+

 GCC is distributed in the hope that it will be useful, but WITHOUT
 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 for more details.
 GCC is distributed in the hope that it will be useful, but WITHOUT
 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 for more details.

-   
+

 You should have received a copy of the GNU General Public License
 along with GCC; see the file COPYING3.  If not see
 <http://www.gnu.org/licenses/>.  */
 You should have received a copy of the GNU General Public License
 along with GCC; see the file COPYING3.  If not see
 <http://www.gnu.org/licenses/>.  */


@@ -34,7 +35,7 @@ along with GCC; see the file COPYING3.  If not see
    iv_analysis_done () to clean up the memory.
 
    The available functions are:
    iv_analysis_done () to clean up the memory.
 
    The available functions are:

- 
+

    iv_analyze (insn, reg, iv): Stores the description of the induction variable
      corresponding to the use of register REG in INSN to IV.  Returns true if
      REG is an induction variable in INSN. false otherwise.
    iv_analyze (insn, reg, iv): Stores the description of the induction variable
      corresponding to the use of register REG in INSN to IV.  Returns true if
      REG is an induction variable in INSN. false otherwise.


@@ -167,14 +168,14 @@ lowpart_subreg (enum machine_mode outer_mode, rtx expr,
                              subreg_lowpart_offset (outer_mode, inner_mode));
 }
 
                              subreg_lowpart_offset (outer_mode, inner_mode));
 }
 

-static void 
+static void

 check_iv_ref_table_size (void)
 {
   if (iv_ref_table_size < DF_DEFS_TABLE_SIZE())
     {
       unsigned int new_size = DF_DEFS_TABLE_SIZE () + (DF_DEFS_TABLE_SIZE () / 4);
       iv_ref_table = XRESIZEVEC (struct rtx_iv *, iv_ref_table, new_size);
 check_iv_ref_table_size (void)
 {
   if (iv_ref_table_size < DF_DEFS_TABLE_SIZE())
     {
       unsigned int new_size = DF_DEFS_TABLE_SIZE () + (DF_DEFS_TABLE_SIZE () / 4);
       iv_ref_table = XRESIZEVEC (struct rtx_iv *, iv_ref_table, new_size);

-      memset (&iv_ref_table[iv_ref_table_size], 0, 
+      memset (&iv_ref_table[iv_ref_table_size], 0,

              (new_size - iv_ref_table_size) * sizeof (struct rtx_iv *));
       iv_ref_table_size = new_size;
     }
              (new_size - iv_ref_table_size) * sizeof (struct rtx_iv *));
       iv_ref_table_size = new_size;
     }


@@ -277,6 +278,7 @@ iv_analysis_loop_init (struct loop *loop)
   df_remove_problem (df_chain);
   df_process_deferred_rescans ();
   df_chain_add_problem (DF_UD_CHAIN);
   df_remove_problem (df_chain);
   df_process_deferred_rescans ();
   df_chain_add_problem (DF_UD_CHAIN);

+  df_note_add_problem ();

   df_set_blocks (blocks);
   df_analyze ();
   if (dump_file)
   df_set_blocks (blocks);
   df_analyze ();
   if (dump_file)


@@ -328,7 +330,7 @@ iv_get_reaching_def (rtx insn, rtx reg, df_ref *def)
   basic_block def_bb, use_bb;
   rtx def_insn;
   bool dom_p;
   basic_block def_bb, use_bb;
   rtx def_insn;
   bool dom_p;

-  
+

   *def = NULL;
   if (!simple_reg_p (reg))
     return GRD_INVALID;
   *def = NULL;
   if (!simple_reg_p (reg))
     return GRD_INVALID;


@@ -857,7 +859,7 @@ iv_analyze_biv (rtx def, struct rtx_iv *iv)
       print_rtl (dump_file, def);
       fprintf (dump_file, " for bivness.\n");
     }
       print_rtl (dump_file, def);
       fprintf (dump_file, " for bivness.\n");
     }

-    
+

   if (!REG_P (def))
     {
       if (!CONSTANT_P (def))
   if (!REG_P (def))
     {
       if (!CONSTANT_P (def))


@@ -917,7 +919,7 @@ iv_analyze_biv (rtx def, struct rtx_iv *iv)
   return iv->base != NULL_RTX;
 }
 
   return iv->base != NULL_RTX;
 }
 

-/* Analyzes expression RHS used at INSN and stores the result to *IV. 
+/* Analyzes expression RHS used at INSN and stores the result to *IV.

    The mode of the induction variable is MODE.  */
 
 bool
    The mode of the induction variable is MODE.  */
 
 bool


@@ -941,7 +943,7 @@ iv_analyze_expr (rtx insn, rtx rhs, enum machine_mode mode, struct rtx_iv *iv)
     {
       if (!iv_analyze_op (insn, rhs, iv))
        return false;
     {
       if (!iv_analyze_op (insn, rhs, iv))
        return false;

-       
+

       if (iv->mode == VOIDmode)
        {
          iv->mode = mode;
       if (iv->mode == VOIDmode)
        {
          iv->mode = mode;


@@ -1055,7 +1057,7 @@ iv_analyze_def (df_ref def, struct rtx_iv *iv)
       fprintf (dump_file, " in insn ");
       print_rtl_single (dump_file, insn);
     }
       fprintf (dump_file, " in insn ");
       print_rtl_single (dump_file, insn);
     }

-  
+

   check_iv_ref_table_size ();
   if (DF_REF_IV (def))
     {
   check_iv_ref_table_size ();
   if (DF_REF_IV (def))
     {


@@ -1118,7 +1120,7 @@ iv_analyze_op (rtx insn, rtx op, struct rtx_iv *iv)
       print_rtl_single (dump_file, insn);
     }
 
       print_rtl_single (dump_file, insn);
     }
 

-  if (CONSTANT_P (op))
+  if (function_invariant_p (op))

     res = GRD_INVARIANT;
   else if (GET_CODE (op) == SUBREG)
     {
     res = GRD_INVARIANT;
   else if (GET_CODE (op) == SUBREG)
     {


@@ -1327,7 +1329,7 @@ simple_rhs_p (rtx rhs)
 {
   rtx op0, op1;
 
 {
   rtx op0, op1;
 

-  if (CONSTANT_P (rhs)
+  if (function_invariant_p (rhs)

       || (REG_P (rhs) && !HARD_REGISTER_P (rhs)))
     return true;
 
       || (REG_P (rhs) && !HARD_REGISTER_P (rhs)))
     return true;
 


@@ -1335,25 +1337,29 @@ simple_rhs_p (rtx rhs)
     {
     case PLUS:
     case MINUS:
     {
     case PLUS:
     case MINUS:

+    case AND:

       op0 = XEXP (rhs, 0);
       op1 = XEXP (rhs, 1);
       op0 = XEXP (rhs, 0);
       op1 = XEXP (rhs, 1);

-      /* Allow reg + const and reg + reg.  */
+      /* Allow reg OP const and reg OP reg.  */

       if (!(REG_P (op0) && !HARD_REGISTER_P (op0))
       if (!(REG_P (op0) && !HARD_REGISTER_P (op0))

-         && !CONSTANT_P (op0))
+         && !function_invariant_p (op0))

        return false;
       if (!(REG_P (op1) && !HARD_REGISTER_P (op1))
        return false;
       if (!(REG_P (op1) && !HARD_REGISTER_P (op1))

-         && !CONSTANT_P (op1))
+         && !function_invariant_p (op1))

        return false;
 
       return true;
 
     case ASHIFT:
        return false;
 
       return true;
 
     case ASHIFT:

+    case ASHIFTRT:
+    case LSHIFTRT:
+    case MULT:

       op0 = XEXP (rhs, 0);
       op1 = XEXP (rhs, 1);
       op0 = XEXP (rhs, 0);
       op1 = XEXP (rhs, 1);

-      /* Allow reg << const.  */
+      /* Allow reg OP const.  */

       if (!(REG_P (op0) && !HARD_REGISTER_P (op0)))
        return false;
       if (!(REG_P (op0) && !HARD_REGISTER_P (op0)))
        return false;

-      if (!CONSTANT_P (op1))
+      if (!function_invariant_p (op1))

        return false;
 
       return true;
        return false;
 
       return true;


@@ -1363,39 +1369,74 @@ simple_rhs_p (rtx rhs)
     }
 }
 
     }
 }
 

-/* Simplifies *EXPR using assignment in INSN.  ALTERED is the set of registers
-   altered so far.  */
+/* If REG has a single definition, replace it with its known value in EXPR.
+   Callback for for_each_rtx.  */

 
 

-static void
-simplify_using_assignment (rtx insn, rtx *expr, regset altered)
+static int
+replace_single_def_regs (rtx *reg, void *expr1)

 {
 {

-  rtx set = single_set (insn);
-  rtx lhs = NULL_RTX, rhs;
-  bool ret = false;
+  unsigned regno;
+  df_ref adef;
+  rtx set, src;
+  rtx *expr = (rtx *)expr1;

 
 

-  if (set)
-    {
-      lhs = SET_DEST (set);
-      if (!REG_P (lhs)
-         || altered_reg_used (&lhs, altered))
-       ret = true;
-    }
-  else
-    ret = true;
+  if (!REG_P (*reg))
+    return 0;

 
 

-  note_stores (PATTERN (insn), mark_altered, altered);
-  if (CALL_P (insn))
+  regno = REGNO (*reg);
+  for (;;)

     {
     {

-      int i;
+      rtx note;
+      adef = DF_REG_DEF_CHAIN (regno);
+      if (adef == NULL || DF_REF_NEXT_REG (adef) != NULL
+           || DF_REF_IS_ARTIFICIAL (adef))
+       return -1;
+
+      set = single_set (DF_REF_INSN (adef));
+      if (set == NULL || !REG_P (SET_DEST (set))
+         || REGNO (SET_DEST (set)) != regno)
+       return -1;

 
 

-      /* Kill all call clobbered registers.  */
-      for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
-       if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i))
-         SET_REGNO_REG_SET (altered, i);
+      note = find_reg_equal_equiv_note (DF_REF_INSN (adef));
+
+      if (note && function_invariant_p (XEXP (note, 0)))
+       {
+         src = XEXP (note, 0);
+         break;
+       }
+      src = SET_SRC (set);
+
+      if (REG_P (src))
+       {
+         regno = REGNO (src);
+         continue;
+       }
+      break;

     }
     }

+  if (!function_invariant_p (src))
+    return -1;

 
 

-  if (ret)
-    return;
+  *expr = simplify_replace_rtx (*expr, *reg, src);
+  return 1;
+}
+
+/* A subroutine of simplify_using_initial_values, this function examines INSN
+   to see if it contains a suitable set that we can use to make a replacement.
+   If it is suitable, return true and set DEST and SRC to the lhs and rhs of
+   the set; return false otherwise.  */
+
+static bool
+suitable_set_for_replacement (rtx insn, rtx *dest, rtx *src)
+{
+  rtx set = single_set (insn);
+  rtx lhs = NULL_RTX, rhs;
+
+  if (!set)
+    return false;
+
+  lhs = SET_DEST (set);
+  if (!REG_P (lhs))
+    return false;

 
   rhs = find_reg_equal_equiv_note (insn);
   if (rhs)
 
   rhs = find_reg_equal_equiv_note (insn);
   if (rhs)


@@ -1404,12 +1445,25 @@ simplify_using_assignment (rtx insn, rtx *expr, regset altered)
     rhs = SET_SRC (set);
 
   if (!simple_rhs_p (rhs))
     rhs = SET_SRC (set);
 
   if (!simple_rhs_p (rhs))

-    return;
+    return false;

 
 

-  if (for_each_rtx (&rhs, altered_reg_used, altered))
-    return;
+  *dest = lhs;
+  *src = rhs;
+  return true;
+}

 
 

-  *expr = simplify_replace_rtx (*expr, lhs, rhs);
+/* Using the data returned by suitable_set_for_replacement, replace DEST
+   with SRC in *EXPR and return the new expression.  Also call
+   replace_single_def_regs if the replacement changed something.  */
+static void
+replace_in_expr (rtx *expr, rtx dest, rtx src)
+{
+  rtx old = *expr;
+  *expr = simplify_replace_rtx (*expr, dest, src);
+  if (old == *expr)
+    return;
+  while (for_each_rtx (expr, replace_single_def_regs, expr) != 0)
+    continue;

 }
 
 /* Checks whether A implies B.  */
 }
 
 /* Checks whether A implies B.  */


@@ -1514,11 +1568,11 @@ implies_p (rtx a, rtx b)
 
   /* A != N is equivalent to A - (N + 1) <u -1.  */
   if (GET_CODE (a) == NE
 
   /* A != N is equivalent to A - (N + 1) <u -1.  */
   if (GET_CODE (a) == NE

-      && GET_CODE (op1) == CONST_INT
+      && CONST_INT_P (op1)

       && GET_CODE (b) == LTU
       && opb1 == constm1_rtx
       && GET_CODE (opb0) == PLUS
       && GET_CODE (b) == LTU
       && opb1 == constm1_rtx
       && GET_CODE (opb0) == PLUS

-      && GET_CODE (XEXP (opb0, 1)) == CONST_INT
+      && CONST_INT_P (XEXP (opb0, 1))

       /* Avoid overflows.  */
       && ((unsigned HOST_WIDE_INT) INTVAL (XEXP (opb0, 1))
          != ((unsigned HOST_WIDE_INT)1
       /* Avoid overflows.  */
       && ((unsigned HOST_WIDE_INT) INTVAL (XEXP (opb0, 1))
          != ((unsigned HOST_WIDE_INT)1


@@ -1528,12 +1582,12 @@ implies_p (rtx a, rtx b)
 
   /* Likewise, A != N implies A - N > 0.  */
   if (GET_CODE (a) == NE
 
   /* Likewise, A != N implies A - N > 0.  */
   if (GET_CODE (a) == NE

-      && GET_CODE (op1) == CONST_INT)
+      && CONST_INT_P (op1))

     {
       if (GET_CODE (b) == GTU
          && GET_CODE (opb0) == PLUS
          && opb1 == const0_rtx
     {
       if (GET_CODE (b) == GTU
          && GET_CODE (opb0) == PLUS
          && opb1 == const0_rtx

-         && GET_CODE (XEXP (opb0, 1)) == CONST_INT
+         && CONST_INT_P (XEXP (opb0, 1))

          /* Avoid overflows.  */
          && ((unsigned HOST_WIDE_INT) INTVAL (XEXP (opb0, 1))
              != ((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT - 1)))
          /* Avoid overflows.  */
          && ((unsigned HOST_WIDE_INT) INTVAL (XEXP (opb0, 1))
              != ((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT - 1)))


@@ -1542,7 +1596,7 @@ implies_p (rtx a, rtx b)
       if (GET_CODE (b) == GEU
          && GET_CODE (opb0) == PLUS
          && opb1 == const1_rtx
       if (GET_CODE (b) == GEU
          && GET_CODE (opb0) == PLUS
          && opb1 == const1_rtx

-         && GET_CODE (XEXP (opb0, 1)) == CONST_INT
+         && CONST_INT_P (XEXP (opb0, 1))

          /* Avoid overflows.  */
          && ((unsigned HOST_WIDE_INT) INTVAL (XEXP (opb0, 1))
              != ((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT - 1)))
          /* Avoid overflows.  */
          && ((unsigned HOST_WIDE_INT) INTVAL (XEXP (opb0, 1))
              != ((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT - 1)))


@@ -1552,11 +1606,12 @@ implies_p (rtx a, rtx b)
 
   /* A >s X, where X is positive, implies A <u Y, if Y is negative.  */
   if ((GET_CODE (a) == GT || GET_CODE (a) == GE)
 
   /* A >s X, where X is positive, implies A <u Y, if Y is negative.  */
   if ((GET_CODE (a) == GT || GET_CODE (a) == GE)

-      && GET_CODE (op1) == CONST_INT
+      && CONST_INT_P (op1)

       && ((GET_CODE (a) == GT && op1 == constm1_rtx)
          || INTVAL (op1) >= 0)
       && GET_CODE (b) == LTU
       && ((GET_CODE (a) == GT && op1 == constm1_rtx)
          || INTVAL (op1) >= 0)
       && GET_CODE (b) == LTU

-      && GET_CODE (opb1) == CONST_INT)
+      && CONST_INT_P (opb1)
+      && rtx_equal_p (op0, opb0))

     return INTVAL (opb1) < 0;
 
   return false;
     return INTVAL (opb1) < 0;
 
   return false;


@@ -1594,7 +1649,7 @@ canon_condition (rtx cond)
     mode = GET_MODE (op1);
   gcc_assert (mode != VOIDmode);
 
     mode = GET_MODE (op1);
   gcc_assert (mode != VOIDmode);
 

-  if (GET_CODE (op1) == CONST_INT
+  if (CONST_INT_P (op1)

       && GET_MODE_CLASS (mode) != MODE_CC
       && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT)
     {
       && GET_MODE_CLASS (mode) != MODE_CC
       && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT)
     {


@@ -1651,15 +1706,22 @@ simplify_using_condition (rtx cond, rtx *expr, regset altered)
 {
   rtx rev, reve, exp = *expr;
 
 {
   rtx rev, reve, exp = *expr;
 

-  if (!COMPARISON_P (exp))
-    return;
-

   /* If some register gets altered later, we do not really speak about its
      value at the time of comparison.  */
   if (altered
       && for_each_rtx (&cond, altered_reg_used, altered))
     return;
 
   /* If some register gets altered later, we do not really speak about its
      value at the time of comparison.  */
   if (altered
       && for_each_rtx (&cond, altered_reg_used, altered))
     return;
 

+  if (GET_CODE (cond) == EQ
+      && REG_P (XEXP (cond, 0)) && CONSTANT_P (XEXP (cond, 1)))
+    {
+      *expr = simplify_replace_rtx (*expr, XEXP (cond, 0), XEXP (cond, 1));
+      return;
+    }
+
+  if (!COMPARISON_P (exp))
+    return;
+

   rev = reversed_condition (cond);
   reve = reversed_condition (exp);
 
   rev = reversed_condition (cond);
   reve = reversed_condition (exp);
 


@@ -1676,7 +1738,6 @@ simplify_using_condition (rtx cond, rtx *expr, regset altered)
       return;
     }
 
       return;
     }
 

-

   if (rev && rtx_equal_p (exp, rev))
     {
       *expr = const0_rtx;
   if (rev && rtx_equal_p (exp, rev))
     {
       *expr = const0_rtx;


@@ -1688,7 +1749,7 @@ simplify_using_condition (rtx cond, rtx *expr, regset altered)
       *expr = const_true_rtx;
       return;
     }
       *expr = const_true_rtx;
       return;
     }

-  
+

   if (reve && implies_p (cond, reve))
     {
       *expr = const0_rtx;
   if (reve && implies_p (cond, reve))
     {
       *expr = const0_rtx;


@@ -1760,9 +1821,10 @@ eliminate_implied_conditions (enum rtx_code op, rtx *head, rtx tail)
 static void
 simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 {
 static void
 simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 {

-  rtx head, tail, insn;
+  bool expression_valid;
+  rtx head, tail, insn, cond_list, last_valid_expr;

   rtx neutral, aggr;
   rtx neutral, aggr;

-  regset altered;
+  regset altered, this_altered;

   edge e;
 
   if (!*expr)
   edge e;
 
   if (!*expr)


@@ -1793,7 +1855,7 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
        default:
          gcc_unreachable ();
        }
        default:
          gcc_unreachable ();
        }

-      
+

       simplify_using_initial_values (loop, UNKNOWN, &head);
       if (head == aggr)
        {
       simplify_using_initial_values (loop, UNKNOWN, &head);
       if (head == aggr)
        {


@@ -1814,7 +1876,7 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
          *expr = tail;
          return;
        }
          *expr = tail;
          return;
        }

-  
+

       XEXP (*expr, 0) = head;
       XEXP (*expr, 1) = tail;
       return;
       XEXP (*expr, 0) = head;
       XEXP (*expr, 1) = tail;
       return;


@@ -1822,48 +1884,122 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 
   gcc_assert (op == UNKNOWN);
 
 
   gcc_assert (op == UNKNOWN);
 

+  for (;;)
+    if (for_each_rtx (expr, replace_single_def_regs, expr) == 0)
+      break;
+  if (CONSTANT_P (*expr))
+    return;
+

   e = loop_preheader_edge (loop);
   if (e->src == ENTRY_BLOCK_PTR)
     return;
 
   altered = ALLOC_REG_SET (&reg_obstack);
   e = loop_preheader_edge (loop);
   if (e->src == ENTRY_BLOCK_PTR)
     return;
 
   altered = ALLOC_REG_SET (&reg_obstack);

+  this_altered = ALLOC_REG_SET (&reg_obstack);

 
 

+  expression_valid = true;
+  last_valid_expr = *expr;
+  cond_list = NULL_RTX;

   while (1)
     {
       insn = BB_END (e->src);
       if (any_condjump_p (insn))
        {
          rtx cond = get_condition (BB_END (e->src), NULL, false, true);
   while (1)
     {
       insn = BB_END (e->src);
       if (any_condjump_p (insn))
        {
          rtx cond = get_condition (BB_END (e->src), NULL, false, true);

-      
+

          if (cond && (e->flags & EDGE_FALLTHRU))
            cond = reversed_condition (cond);
          if (cond)
            {
          if (cond && (e->flags & EDGE_FALLTHRU))
            cond = reversed_condition (cond);
          if (cond)
            {

+             rtx old = *expr;

              simplify_using_condition (cond, expr, altered);
              simplify_using_condition (cond, expr, altered);

-             if (CONSTANT_P (*expr))
+             if (old != *expr)

                {
                {

-                 FREE_REG_SET (altered);
-                 return;
+                 rtx note;
+                 if (CONSTANT_P (*expr))
+                   goto out;
+                 for (note = cond_list; note; note = XEXP (note, 1))
+                   {
+                     simplify_using_condition (XEXP (note, 0), expr, altered);
+                     if (CONSTANT_P (*expr))
+                       goto out;
+                   }

                }
                }

+             cond_list = alloc_EXPR_LIST (0, cond, cond_list);

            }
        }
 
       FOR_BB_INSNS_REVERSE (e->src, insn)
        {
            }
        }
 
       FOR_BB_INSNS_REVERSE (e->src, insn)
        {

+         rtx src, dest;
+         rtx old = *expr;
+

          if (!INSN_P (insn))
            continue;
          if (!INSN_P (insn))
            continue;

-           
-         simplify_using_assignment (insn, expr, altered);
-         if (CONSTANT_P (*expr))
+
+         CLEAR_REG_SET (this_altered);
+         note_stores (PATTERN (insn), mark_altered, this_altered);
+         if (CALL_P (insn))

            {
            {

-             FREE_REG_SET (altered);
-             return;
+             int i;
+
+             /* Kill all call clobbered registers.  */
+             for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+               if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i))
+                 SET_REGNO_REG_SET (this_altered, i);

            }
            }

-         if (for_each_rtx (expr, altered_reg_used, altered))
+
+         if (suitable_set_for_replacement (insn, &dest, &src))

            {
            {

-             FREE_REG_SET (altered);
-             return;
+             rtx *pnote, *pnote_next;
+
+             replace_in_expr (expr, dest, src);
+             if (CONSTANT_P (*expr))
+               goto out;
+
+             for (pnote = &cond_list; *pnote; pnote = pnote_next)
+               {
+                 rtx note = *pnote;
+                 rtx old_cond = XEXP (note, 0);
+
+                 pnote_next = &XEXP (note, 1);
+                 replace_in_expr (&XEXP (note, 0), dest, src);
+
+                 /* We can no longer use a condition that has been simplified
+                    to a constant, and simplify_using_condition will abort if
+                    we try.  */
+                 if (CONSTANT_P (XEXP (note, 0)))
+                   {
+                     *pnote = *pnote_next;
+                     pnote_next = pnote;
+                     free_EXPR_LIST_node (note);
+                   }
+                 /* Retry simplifications with this condition if either the
+                    expression or the condition changed.  */
+                 else if (old_cond != XEXP (note, 0) || old != *expr)
+                   simplify_using_condition (XEXP (note, 0), expr, altered);
+               }

            }
            }

+         else
+           /* If we did not use this insn to make a replacement, any overlap
+              between stores in this insn and our expression will cause the
+              expression to become invalid.  */
+           if (for_each_rtx (expr, altered_reg_used, this_altered))
+             goto out;
+
+         if (CONSTANT_P (*expr))
+           goto out;
+
+         IOR_REG_SET (altered, this_altered);
+
+         /* If the expression now contains regs that have been altered, we
+            can't return it to the caller.  However, it is still valid for
+            further simplification, so keep searching to see if we can
+            eventually turn it into a constant.  */
+         if (for_each_rtx (expr, altered_reg_used, altered))
+           expression_valid = false;
+         if (expression_valid)
+           last_valid_expr = *expr;

        }
 
       if (!single_pred_p (e->src)
        }
 
       if (!single_pred_p (e->src)


@@ -1872,7 +2008,12 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
       e = single_pred_edge (e->src);
     }
 
       e = single_pred_edge (e->src);
     }
 

+ out:
+  free_EXPR_LIST_list (&cond_list);
+  if (!CONSTANT_P (*expr))
+    *expr = last_valid_expr;

   FREE_REG_SET (altered);
   FREE_REG_SET (altered);

+  FREE_REG_SET (this_altered);

 }
 
 /* Transforms invariant IV into MODE.  Adds assumptions based on the fact
 }
 
 /* Transforms invariant IV into MODE.  Adds assumptions based on the fact


@@ -1996,7 +2137,7 @@ canonicalize_iv_subregs (struct rtx_iv *iv0, struct rtx_iv *iv1,
      and iv0 and iv1 are both ivs iterating in SI mode, but calculated
      in different modes.  This does not seem impossible to handle, but
      it hardly ever occurs in practice.
      and iv0 and iv1 are both ivs iterating in SI mode, but calculated
      in different modes.  This does not seem impossible to handle, but
      it hardly ever occurs in practice.

-     
+

      The only exception is the case when one of operands is invariant.
      For example pentium 3 generates comparisons like
      (lt (subreg:HI (reg:SI)) 100).  Here we assign HImode to 100, but we
      The only exception is the case when one of operands is invariant.
      For example pentium 3 generates comparisons like
      (lt (subreg:HI (reg:SI)) 100).  Here we assign HImode to 100, but we


@@ -2049,17 +2190,20 @@ canonicalize_iv_subregs (struct rtx_iv *iv0, struct rtx_iv *iv1,
   return true;
 }
 
   return true;
 }
 

-/* Tries to estimate the maximum number of iterations.  */
+/* Tries to estimate the maximum number of iterations in LOOP, and store the
+   result in DESC.  This function is called from iv_number_of_iterations with
+   a number of fields in DESC already filled in.  OLD_NITER is the original
+   expression for the number of iterations, before we tried to simplify it.  */

 
 static unsigned HOST_WIDEST_INT
 
 static unsigned HOST_WIDEST_INT

-determine_max_iter (struct loop *loop, struct niter_desc *desc)
+determine_max_iter (struct loop *loop, struct niter_desc *desc, rtx old_niter)

 {
   rtx niter = desc->niter_expr;
   rtx mmin, mmax, cmp;
   unsigned HOST_WIDEST_INT nmax, inc;
 
   if (GET_CODE (niter) == AND
 {
   rtx niter = desc->niter_expr;
   rtx mmin, mmax, cmp;
   unsigned HOST_WIDEST_INT nmax, inc;
 
   if (GET_CODE (niter) == AND

-      && GET_CODE (XEXP (niter, 0)) == CONST_INT)
+      && CONST_INT_P (XEXP (niter, 0)))

     {
       nmax = INTVAL (XEXP (niter, 0));
       if (!(nmax & (nmax + 1)))
     {
       nmax = INTVAL (XEXP (niter, 0));
       if (!(nmax & (nmax + 1)))


@@ -2074,7 +2218,7 @@ determine_max_iter (struct loop *loop, struct niter_desc *desc)
 
   if (GET_CODE (niter) == UDIV)
     {
 
   if (GET_CODE (niter) == UDIV)
     {

-      if (GET_CODE (XEXP (niter, 1)) != CONST_INT)
+      if (!CONST_INT_P (XEXP (niter, 1)))

        {
          desc->niter_max = nmax;
          return nmax;
        {
          desc->niter_max = nmax;
          return nmax;


@@ -2087,7 +2231,8 @@ determine_max_iter (struct loop *loop, struct niter_desc *desc)
 
   /* We could use a binary search here, but for now improving the upper
      bound by just one eliminates one important corner case.  */
 
   /* We could use a binary search here, but for now improving the upper
      bound by just one eliminates one important corner case.  */

-  cmp = gen_rtx_fmt_ee (desc->signed_p ? LT : LTU, VOIDmode, niter, mmax);
+  cmp = simplify_gen_relational (desc->signed_p ? LT : LTU, VOIDmode,
+                                desc->mode, old_niter, mmax);

   simplify_using_initial_values (loop, UNKNOWN, &cmp);
   if (cmp == const_true_rtx)
     {
   simplify_using_initial_values (loop, UNKNOWN, &cmp);
   if (cmp == const_true_rtx)
     {


@@ -2154,7 +2299,7 @@ iv_number_of_iterations (struct loop *loop, rtx insn, rtx condition,
     goto fail;
   if (iv0.extend_mode == VOIDmode)
     iv0.mode = iv0.extend_mode = mode;
     goto fail;
   if (iv0.extend_mode == VOIDmode)
     iv0.mode = iv0.extend_mode = mode;

-  
+

   op1 = XEXP (condition, 1);
   if (!iv_analyze (insn, op1, &iv1))
     goto fail;
   op1 = XEXP (condition, 1);
   if (!iv_analyze (insn, op1, &iv1))
     goto fail;


@@ -2201,7 +2346,7 @@ iv_number_of_iterations (struct loop *loop, rtx insn, rtx condition,
   mode_mmin = lowpart_subreg (mode, mmin, comp_mode);
   mode_mmax = lowpart_subreg (mode, mmax, comp_mode);
 
   mode_mmin = lowpart_subreg (mode, mmin, comp_mode);
   mode_mmax = lowpart_subreg (mode, mmax, comp_mode);
 

-  if (GET_CODE (iv0.step) != CONST_INT || GET_CODE (iv1.step) != CONST_INT)
+  if (!CONST_INT_P (iv0.step) || !CONST_INT_P (iv1.step))

     goto fail;
 
   /* We can take care of the case of two induction variables chasing each other
     goto fail;
 
   /* We can take care of the case of two induction variables chasing each other


@@ -2332,7 +2477,7 @@ iv_number_of_iterations (struct loop *loop, rtx insn, rtx condition,
       may_xform = const0_rtx;
       may_not_xform = const_true_rtx;
 
       may_xform = const0_rtx;
       may_not_xform = const_true_rtx;
 

-      if (GET_CODE (delta) == CONST_INT)
+      if (CONST_INT_P (delta))

        {
          if (was_sharp && INTVAL (delta) == INTVAL (step) - 1)
            {
        {
          if (was_sharp && INTVAL (delta) == INTVAL (step) - 1)
            {


@@ -2395,11 +2540,11 @@ iv_number_of_iterations (struct loop *loop, rtx insn, rtx condition,
             number of iterations in this step, so record the information
             here.  */
          inc = INTVAL (iv0.step) - INTVAL (iv1.step);
             number of iterations in this step, so record the information
             here.  */
          inc = INTVAL (iv0.step) - INTVAL (iv1.step);

-         if (GET_CODE (iv1.base) == CONST_INT)
+         if (CONST_INT_P (iv1.base))

            up = INTVAL (iv1.base);
          else
            up = INTVAL (mode_mmax) - inc;
            up = INTVAL (iv1.base);
          else
            up = INTVAL (mode_mmax) - inc;

-         down = INTVAL (GET_CODE (iv0.base) == CONST_INT
+         down = INTVAL (CONST_INT_P (iv0.base)

                         ? iv0.base
                         : mode_mmin);
          desc->niter_max = (up - down) / inc + 1;
                         ? iv0.base
                         : mode_mmin);
          desc->niter_max = (up - down) / inc + 1;


@@ -2608,7 +2753,7 @@ iv_number_of_iterations (struct loop *loop, rtx insn, rtx condition,
       && XEXP (desc->noloop_assumptions, 0) == const_true_rtx)
     goto zero_iter;
 
       && XEXP (desc->noloop_assumptions, 0) == const_true_rtx)
     goto zero_iter;
 

-  if (GET_CODE (desc->niter_expr) == CONST_INT)
+  if (CONST_INT_P (desc->niter_expr))

     {
       unsigned HOST_WIDEST_INT val = INTVAL (desc->niter_expr);
 
     {
       unsigned HOST_WIDEST_INT val = INTVAL (desc->niter_expr);
 


@@ -2618,7 +2763,7 @@ iv_number_of_iterations (struct loop *loop, rtx insn, rtx condition,
   else
     {
       if (!desc->niter_max)
   else
     {
       if (!desc->niter_max)

-       desc->niter_max = determine_max_iter (loop, desc);
+       desc->niter_max = determine_max_iter (loop, desc, old_niter);

 
       /* simplify_using_initial_values does a copy propagation on the registers
         in the expression for the number of iterations.  This prolongs life
 
       /* simplify_using_initial_values does a copy propagation on the registers
         in the expression for the number of iterations.  This prolongs life


@@ -2722,7 +2867,7 @@ find_simple_exit (struct loop *loop, struct niter_desc *desc)
        {
          if (flow_bb_inside_loop_p (loop, e->dest))
            continue;
        {
          if (flow_bb_inside_loop_p (loop, e->dest))
            continue;

-         
+

          check_simple_exit (loop, e, &act);
          if (!act.simple_p)
            continue;
          check_simple_exit (loop, e, &act);
          if (!act.simple_p)
            continue;


@@ -2741,7 +2886,7 @@ find_simple_exit (struct loop *loop, struct niter_desc *desc)
              if (act.infinite && !desc->infinite)
                continue;
            }
              if (act.infinite && !desc->infinite)
                continue;
            }

-         
+

          *desc = act;
        }
     }
          *desc = act;
        }
     }


@@ -2799,22 +2944,24 @@ get_simple_loop_desc (struct loop *loop)
   if (desc)
     return desc;
 
   if (desc)
     return desc;
 

-  desc = XNEW (struct niter_desc);
+  /* At least desc->infinite is not always initialized by
+     find_simple_loop_exit.  */
+  desc = XCNEW (struct niter_desc);

   iv_analysis_loop_init (loop);
   find_simple_exit (loop, desc);
   loop->aux = desc;
 
   if (desc->simple_p && (desc->assumptions || desc->infinite))
     {
   iv_analysis_loop_init (loop);
   find_simple_exit (loop, desc);
   loop->aux = desc;
 
   if (desc->simple_p && (desc->assumptions || desc->infinite))
     {

-      const char *wording; 
+      const char *wording;

 
 

-      /* Assume that no overflow happens and that the loop is finite.  
+      /* Assume that no overflow happens and that the loop is finite.

         We already warned at the tree level if we ran optimizations there.  */
       if (!flag_tree_loop_optimize && warn_unsafe_loop_optimizations)
        {
          if (desc->infinite)
            {
         We already warned at the tree level if we ran optimizations there.  */
       if (!flag_tree_loop_optimize && warn_unsafe_loop_optimizations)
        {
          if (desc->infinite)
            {

-             wording = 
+             wording =

                flag_unsafe_loop_optimizations
                ? N_("assuming that the loop is not infinite")
                : N_("cannot optimize possibly infinite loops");
                flag_unsafe_loop_optimizations
                ? N_("assuming that the loop is not infinite")
                : N_("cannot optimize possibly infinite loops");


@@ -2823,7 +2970,7 @@ get_simple_loop_desc (struct loop *loop)
            }
          if (desc->assumptions)
            {
            }
          if (desc->assumptions)
            {

-             wording = 
+             wording =

                flag_unsafe_loop_optimizations
                ? N_("assuming that the loop counter does not overflow")
                : N_("cannot optimize loop, the loop counter may overflow");
                flag_unsafe_loop_optimizations
                ? N_("assuming that the loop counter does not overflow")
                : N_("cannot optimize loop, the loop counter may overflow");