Initial checkin of GCC 4.9.0 from trunk (r208799).

Change-Id: I48a3c08bb98542aa215912a75f03c0890e497dba

1 files changed, 2884 insertions, 0 deletions

diff --git a/gcc-4.9/gcc/cselib.c b/gcc-4.9/gcc/cselib.c
new file mode 100644
index 000000000..26bcbe077
--- /dev/null
+++ b/gcc-4.9/gcc/cselib.c
@@ -0,0 +1,2884 @@
+/* Common subexpression elimination library for GNU compiler.
+   Copyright (C) 1987-2014 Free Software Foundation, Inc.
+
+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 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/>.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+
+#include "rtl.h"
+#include "tree.h"/* FIXME: For hashing DEBUG_EXPR & friends.  */
+#include "tm_p.h"
+#include "regs.h"
+#include "hard-reg-set.h"
+#include "flags.h"
+#include "insn-config.h"
+#include "recog.h"
+#include "function.h"
+#include "emit-rtl.h"
+#include "diagnostic-core.h"
+#include "ggc.h"
+#include "hash-table.h"
+#include "dumpfile.h"
+#include "cselib.h"
+#include "valtrack.h"
+#include "params.h"
+#include "alloc-pool.h"
+#include "target.h"
+#include "bitmap.h"
+
+/* A list of cselib_val structures.  */
+struct elt_list {
+    struct elt_list *next;
+    cselib_val *elt;
+};
+
+/* See the documentation of cselib_find_slot below.  */
+static enum machine_mode find_slot_memmode;
+
+static bool cselib_record_memory;
+static bool cselib_preserve_constants;
+static bool cselib_any_perm_equivs;
+static inline void promote_debug_loc (struct elt_loc_list *l);
+static struct elt_list *new_elt_list (struct elt_list *, cselib_val *);
+static void new_elt_loc_list (cselib_val *, rtx);
+static void unchain_one_value (cselib_val *);
+static void unchain_one_elt_list (struct elt_list **);
+static void unchain_one_elt_loc_list (struct elt_loc_list **);
+static void remove_useless_values (void);
+static int rtx_equal_for_cselib_1 (rtx, rtx, enum machine_mode);
+static unsigned int cselib_hash_rtx (rtx, int, enum machine_mode);
+static cselib_val *new_cselib_val (unsigned int, enum machine_mode, rtx);
+static void add_mem_for_addr (cselib_val *, cselib_val *, rtx);
+static cselib_val *cselib_lookup_mem (rtx, int);
+static void cselib_invalidate_regno (unsigned int, enum machine_mode);
+static void cselib_invalidate_mem (rtx);
+static void cselib_record_set (rtx, cselib_val *, cselib_val *);
+static void cselib_record_sets (rtx);
+
+struct expand_value_data
+{
+  bitmap regs_active;
+  cselib_expand_callback callback;
+  void *callback_arg;
+  bool dummy;
+};
+
+static rtx cselib_expand_value_rtx_1 (rtx, struct expand_value_data *, int);
+
+/* There are three ways in which cselib can look up an rtx:
+   - for a REG, the reg_values table (which is indexed by regno) is used
+   - for a MEM, we recursively look up its address and then follow the
+     addr_list of that value
+   - for everything else, we compute a hash value and go through the hash
+     table.  Since different rtx's can still have the same hash value,
+     this involves walking the table entries for a given value and comparing
+     the locations of the entries with the rtx we are looking up.  */
+
+struct cselib_hasher : typed_noop_remove <cselib_val>
+{
+  typedef cselib_val value_type;
+  typedef rtx_def compare_type;
+  static inline hashval_t hash (const value_type *);
+  static inline bool equal (const value_type *, const compare_type *);
+};
+
+/* The hash function for our hash table.  The value is always computed with
+   cselib_hash_rtx when adding an element; this function just extracts the
+   hash value from a cselib_val structure.  */
+
+inline hashval_t
+cselib_hasher::hash (const value_type *v)
+{
+  return v->hash;
+}
+
+/* The equality test for our hash table.  The first argument V is a table
+   element (i.e. a cselib_val), while the second arg X is an rtx.  We know
+   that all callers of htab_find_slot_with_hash will wrap CONST_INTs into a
+   CONST of an appropriate mode.  */
+
+inline bool
+cselib_hasher::equal (const value_type *v, const compare_type *x_arg)
+{
+  struct elt_loc_list *l;
+  rtx x = CONST_CAST_RTX (x_arg);
+  enum machine_mode mode = GET_MODE (x);
+
+  gcc_assert (!CONST_SCALAR_INT_P (x) && GET_CODE (x) != CONST_FIXED);
+
+  if (mode != GET_MODE (v->val_rtx))
+    return false;
+
+  /* Unwrap X if necessary.  */
+  if (GET_CODE (x) == CONST
+      && (CONST_SCALAR_INT_P (XEXP (x, 0))
+	  || GET_CODE (XEXP (x, 0)) == CONST_FIXED))
+    x = XEXP (x, 0);
+
+  if (GET_CODE (x) == VALUE)
+    return x == v->val_rtx;
+
+  /* We don't guarantee that distinct rtx's have different hash values,
+     so we need to do a comparison.  */
+  for (l = v->locs; l; l = l->next)
+    if (rtx_equal_for_cselib_1 (l->loc, x, find_slot_memmode))
+      {
+	promote_debug_loc (l);
+	return true;
+      }
+
+  return false;
+}
+
+/* A table that enables us to look up elts by their value.  */
+static hash_table <cselib_hasher> cselib_hash_table;
+
+/* A table to hold preserved values.  */
+static hash_table <cselib_hasher> cselib_preserved_hash_table;
+
+/* This is a global so we don't have to pass this through every function.
+   It is used in new_elt_loc_list to set SETTING_INSN.  */
+static rtx cselib_current_insn;
+
+/* The unique id that the next create value will take.  */
+static unsigned int next_uid;
+
+/* The number of registers we had when the varrays were last resized.  */
+static unsigned int cselib_nregs;
+
+/* Count values without known locations, or with only locations that
+   wouldn't have been known except for debug insns.  Whenever this
+   grows too big, we remove these useless values from the table.
+
+   Counting values with only debug values is a bit tricky.  We don't
+   want to increment n_useless_values when we create a value for a
+   debug insn, for this would get n_useless_values out of sync, but we
+   want increment it if all locs in the list that were ever referenced
+   in nondebug insns are removed from the list.
+
+   In the general case, once we do that, we'd have to stop accepting
+   nondebug expressions in the loc list, to avoid having two values
+   equivalent that, without debug insns, would have been made into
+   separate values.  However, because debug insns never introduce
+   equivalences themselves (no assignments), the only means for
+   growing loc lists is through nondebug assignments.  If the locs
+   also happen to be referenced in debug insns, it will work just fine.
+
+   A consequence of this is that there's at most one debug-only loc in
+   each loc list.  If we keep it in the first entry, testing whether
+   we have a debug-only loc list takes O(1).
+
+   Furthermore, since any additional entry in a loc list containing a
+   debug loc would have to come from an assignment (nondebug) that
+   references both the initial debug loc and the newly-equivalent loc,
+   the initial debug loc would be promoted to a nondebug loc, and the
+   loc list would not contain debug locs any more.
+
+   So the only case we have to be careful with in order to keep
+   n_useless_values in sync between debug and nondebug compilations is
+   to avoid incrementing n_useless_values when removing the single loc
+   from a value that turns out to not appear outside debug values.  We
+   increment n_useless_debug_values instead, and leave such values
+   alone until, for other reasons, we garbage-collect useless
+   values.  */
+static int n_useless_values;
+static int n_useless_debug_values;
+
+/* Count values whose locs have been taken exclusively from debug
+   insns for the entire life of the value.  */
+static int n_debug_values;
+
+/* Number of useless values before we remove them from the hash table.  */
+#define MAX_USELESS_VALUES 32
+
+/* This table maps from register number to values.  It does not
+   contain pointers to cselib_val structures, but rather elt_lists.
+   The purpose is to be able to refer to the same register in
+   different modes.  The first element of the list defines the mode in
+   which the register was set; if the mode is unknown or the value is
+   no longer valid in that mode, ELT will be NULL for the first
+   element.  */
+static struct elt_list **reg_values;
+static unsigned int reg_values_size;
+#define REG_VALUES(i) reg_values[i]
+
+/* The largest number of hard regs used by any entry added to the
+   REG_VALUES table.  Cleared on each cselib_clear_table() invocation.  */
+static unsigned int max_value_regs;
+
+/* Here the set of indices I with REG_VALUES(I) != 0 is saved.  This is used
+   in cselib_clear_table() for fast emptying.  */
+static unsigned int *used_regs;
+static unsigned int n_used_regs;
+
+/* We pass this to cselib_invalidate_mem to invalidate all of
+   memory for a non-const call instruction.  */
+static GTY(()) rtx callmem;
+
+/* Set by discard_useless_locs if it deleted the last location of any
+   value.  */
+static int values_became_useless;
+
+/* Used as stop element of the containing_mem list so we can check
+   presence in the list by checking the next pointer.  */
+static cselib_val dummy_val;
+
+/* If non-NULL, value of the eliminated arg_pointer_rtx or frame_pointer_rtx
+   that is constant through the whole function and should never be
+   eliminated.  */
+static cselib_val *cfa_base_preserved_val;
+static unsigned int cfa_base_preserved_regno = INVALID_REGNUM;
+
+/* Used to list all values that contain memory reference.
+   May or may not contain the useless values - the list is compacted
+   each time memory is invalidated.  */
+static cselib_val *first_containing_mem = &dummy_val;
+static alloc_pool elt_loc_list_pool, elt_list_pool, cselib_val_pool, value_pool;
+
+/* If nonnull, cselib will call this function before freeing useless
+   VALUEs.  A VALUE is deemed useless if its "locs" field is null.  */
+void (*cselib_discard_hook) (cselib_val *);
+
+/* If nonnull, cselib will call this function before recording sets or
+   even clobbering outputs of INSN.  All the recorded sets will be
+   represented in the array sets[n_sets].  new_val_min can be used to
+   tell whether values present in sets are introduced by this
+   instruction.  */
+void (*cselib_record_sets_hook) (rtx insn, struct cselib_set *sets,
+				 int n_sets);
+
+#define PRESERVED_VALUE_P(RTX) \
+  (RTL_FLAG_CHECK1 ("PRESERVED_VALUE_P", (RTX), VALUE)->unchanging)
+
+#define SP_BASED_VALUE_P(RTX) \
+  (RTL_FLAG_CHECK1 ("SP_BASED_VALUE_P", (RTX), VALUE)->jump)
+
+
+
+/* Allocate a struct elt_list and fill in its two elements with the
+   arguments.  */
+
+static inline struct elt_list *
+new_elt_list (struct elt_list *next, cselib_val *elt)
+{
+  struct elt_list *el;
+  el = (struct elt_list *) pool_alloc (elt_list_pool);
+  el->next = next;
+  el->elt = elt;
+  return el;
+}
+
+/* Allocate a struct elt_loc_list with LOC and prepend it to VAL's loc
+   list.  */
+
+static inline void
+new_elt_loc_list (cselib_val *val, rtx loc)
+{
+  struct elt_loc_list *el, *next = val->locs;
+
+  gcc_checking_assert (!next || !next->setting_insn
+		       || !DEBUG_INSN_P (next->setting_insn)
+		       || cselib_current_insn == next->setting_insn);
+
+  /* If we're creating the first loc in a debug insn context, we've
+     just created a debug value.  Count it.  */
+  if (!next && cselib_current_insn && DEBUG_INSN_P (cselib_current_insn))
+    n_debug_values++;
+
+  val = canonical_cselib_val (val);
+  next = val->locs;
+
+  if (GET_CODE (loc) == VALUE)
+    {
+      loc = canonical_cselib_val (CSELIB_VAL_PTR (loc))->val_rtx;
+
+      gcc_checking_assert (PRESERVED_VALUE_P (loc)
+			   == PRESERVED_VALUE_P (val->val_rtx));
+
+      if (val->val_rtx == loc)
+	return;
+      else if (val->uid > CSELIB_VAL_PTR (loc)->uid)
+	{
+	  /* Reverse the insertion.  */
+	  new_elt_loc_list (CSELIB_VAL_PTR (loc), val->val_rtx);
+	  return;
+	}
+
+      gcc_checking_assert (val->uid < CSELIB_VAL_PTR (loc)->uid);
+
+      if (CSELIB_VAL_PTR (loc)->locs)
+	{
+	  /* Bring all locs from LOC to VAL.  */
+	  for (el = CSELIB_VAL_PTR (loc)->locs; el->next; el = el->next)
+	    {
+	      /* Adjust values that have LOC as canonical so that VAL
+		 becomes their canonical.  */
+	      if (el->loc && GET_CODE (el->loc) == VALUE)
+		{
+		  gcc_checking_assert (CSELIB_VAL_PTR (el->loc)->locs->loc
+				       == loc);
+		  CSELIB_VAL_PTR (el->loc)->locs->loc = val->val_rtx;
+		}
+	    }
+	  el->next = val->locs;
+	  next = val->locs = CSELIB_VAL_PTR (loc)->locs;
+	}
+
+      if (CSELIB_VAL_PTR (loc)->addr_list)
+	{
+	  /* Bring in addr_list into canonical node.  */
+	  struct elt_list *last = CSELIB_VAL_PTR (loc)->addr_list;
+	  while (last->next)
+	    last = last->next;
+	  last->next = val->addr_list;
+	  val->addr_list = CSELIB_VAL_PTR (loc)->addr_list;
+	  CSELIB_VAL_PTR (loc)->addr_list = NULL;
+	}
+
+      if (CSELIB_VAL_PTR (loc)->next_containing_mem != NULL
+	  && val->next_containing_mem == NULL)
+	{
+	  /* Add VAL to the containing_mem list after LOC.  LOC will
+	     be removed when we notice it doesn't contain any
+	     MEMs.  */
+	  val->next_containing_mem = CSELIB_VAL_PTR (loc)->next_containing_mem;
+	  CSELIB_VAL_PTR (loc)->next_containing_mem = val;
+	}
+
+      /* Chain LOC back to VAL.  */
+      el = (struct elt_loc_list *) pool_alloc (elt_loc_list_pool);
+      el->loc = val->val_rtx;
+      el->setting_insn = cselib_current_insn;
+      el->next = NULL;
+      CSELIB_VAL_PTR (loc)->locs = el;
+    }
+
+  el = (struct elt_loc_list *) pool_alloc (elt_loc_list_pool);
+  el->loc = loc;
+  el->setting_insn = cselib_current_insn;
+  el->next = next;
+  val->locs = el;
+}
+
+/* Promote loc L to a nondebug cselib_current_insn if L is marked as
+   originating from a debug insn, maintaining the debug values
+   count.  */
+
+static inline void
+promote_debug_loc (struct elt_loc_list *l)
+{
+  if (l && l->setting_insn && DEBUG_INSN_P (l->setting_insn)
+      && (!cselib_current_insn || !DEBUG_INSN_P (cselib_current_insn)))
+    {
+      n_debug_values--;
+      l->setting_insn = cselib_current_insn;
+      if (cselib_preserve_constants && l->next)
+	{
+	  gcc_assert (l->next->setting_insn
+		      && DEBUG_INSN_P (l->next->setting_insn)
+		      && !l->next->next);
+	  l->next->setting_insn = cselib_current_insn;
+	}
+      else
+	gcc_assert (!l->next);
+    }
+}
+
+/* The elt_list at *PL is no longer needed.  Unchain it and free its
+   storage.  */
+
+static inline void
+unchain_one_elt_list (struct elt_list **pl)
+{
+  struct elt_list *l = *pl;
+
+  *pl = l->next;
+  pool_free (elt_list_pool, l);
+}
+
+/* Likewise for elt_loc_lists.  */
+
+static void
+unchain_one_elt_loc_list (struct elt_loc_list **pl)
+{
+  struct elt_loc_list *l = *pl;
+
+  *pl = l->next;
+  pool_free (elt_loc_list_pool, l);
+}
+
+/* Likewise for cselib_vals.  This also frees the addr_list associated with
+   V.  */
+
+static void
+unchain_one_value (cselib_val *v)
+{
+  while (v->addr_list)
+    unchain_one_elt_list (&v->addr_list);
+
+  pool_free (cselib_val_pool, v);
+}
+
+/* Remove all entries from the hash table.  Also used during
+   initialization.  */
+
+void
+cselib_clear_table (void)
+{
+  cselib_reset_table (1);
+}
+
+/* Return TRUE if V is a constant, a function invariant or a VALUE
+   equivalence; FALSE otherwise.  */
+
+static bool
+invariant_or_equiv_p (cselib_val *v)
+{
+  struct elt_loc_list *l;
+
+  if (v == cfa_base_preserved_val)
+    return true;
+
+  /* Keep VALUE equivalences around.  */
+  for (l = v->locs; l; l = l->next)
+    if (GET_CODE (l->loc) == VALUE)
+      return true;
+
+  if (v->locs != NULL
+      && v->locs->next == NULL)
+    {
+      if (CONSTANT_P (v->locs->loc)
+	  && (GET_CODE (v->locs->loc) != CONST
+	      || !references_value_p (v->locs->loc, 0)))
+	return true;
+      /* Although a debug expr may be bound to different expressions,
+	 we can preserve it as if it was constant, to get unification
+	 and proper merging within var-tracking.  */
+      if (GET_CODE (v->locs->loc) == DEBUG_EXPR
+	  || GET_CODE (v->locs->loc) == DEBUG_IMPLICIT_PTR
+	  || GET_CODE (v->locs->loc) == ENTRY_VALUE
+	  || GET_CODE (v->locs->loc) == DEBUG_PARAMETER_REF)
+	return true;
+
+      /* (plus (value V) (const_int C)) is invariant iff V is invariant.  */
+      if (GET_CODE (v->locs->loc) == PLUS
+	  && CONST_INT_P (XEXP (v->locs->loc, 1))
+	  && GET_CODE (XEXP (v->locs->loc, 0)) == VALUE
+	  && invariant_or_equiv_p (CSELIB_VAL_PTR (XEXP (v->locs->loc, 0))))
+	return true;
+    }
+
+  return false;
+}
+
+/* Remove from hash table all VALUEs except constants, function
+   invariants and VALUE equivalences.  */
+
+int
+preserve_constants_and_equivs (cselib_val **x, void *info ATTRIBUTE_UNUSED)
+{
+  cselib_val *v = *x;
+
+  if (invariant_or_equiv_p (v))
+    {
+      cselib_val **slot
+	= cselib_preserved_hash_table.find_slot_with_hash (v->val_rtx,
+							   v->hash, INSERT);
+      gcc_assert (!*slot);
+      *slot = v;
+    }
+
+  cselib_hash_table.clear_slot (x);
+
+  return 1;
+}
+
+/* Remove all entries from the hash table, arranging for the next
+   value to be numbered NUM.  */
+
+void
+cselib_reset_table (unsigned int num)
+{
+  unsigned int i;
+
+  max_value_regs = 0;
+
+  if (cfa_base_preserved_val)
+    {
+      unsigned int regno = cfa_base_preserved_regno;
+      unsigned int new_used_regs = 0;
+      for (i = 0; i < n_used_regs; i++)
+	if (used_regs[i] == regno)
+	  {
+	    new_used_regs = 1;
+	    continue;
+	  }
+	else
+	  REG_VALUES (used_regs[i]) = 0;
+      gcc_assert (new_used_regs == 1);
+      n_used_regs = new_used_regs;
+      used_regs[0] = regno;
+      max_value_regs
+	= hard_regno_nregs[regno][GET_MODE (cfa_base_preserved_val->locs->loc)];
+    }
+  else
+    {
+      for (i = 0; i < n_used_regs; i++)
+	REG_VALUES (used_regs[i]) = 0;
+      n_used_regs = 0;
+    }
+
+  if (cselib_preserve_constants)
+    cselib_hash_table.traverse <void *, preserve_constants_and_equivs> (NULL);
+  else
+    {
+      cselib_hash_table.empty ();
+      gcc_checking_assert (!cselib_any_perm_equivs);
+    }
+
+  n_useless_values = 0;
+  n_useless_debug_values = 0;
+  n_debug_values = 0;
+
+  next_uid = num;
+
+  first_containing_mem = &dummy_val;
+}
+
+/* Return the number of the next value that will be generated.  */
+
+unsigned int
+cselib_get_next_uid (void)
+{
+  return next_uid;
+}
+
+/* Search for X, whose hashcode is HASH, in CSELIB_HASH_TABLE,
+   INSERTing if requested.  When X is part of the address of a MEM,
+   MEMMODE should specify the mode of the MEM.  While searching the
+   table, MEMMODE is held in FIND_SLOT_MEMMODE, so that autoinc RTXs
+   in X can be resolved.  */
+
+static cselib_val **
+cselib_find_slot (rtx x, hashval_t hash, enum insert_option insert,
+		  enum machine_mode memmode)
+{
+  cselib_val **slot = NULL;
+  find_slot_memmode = memmode;
+  if (cselib_preserve_constants)
+    slot = cselib_preserved_hash_table.find_slot_with_hash (x, hash,
+							    NO_INSERT);
+  if (!slot)
+    slot = cselib_hash_table.find_slot_with_hash (x, hash, insert);
+  find_slot_memmode = VOIDmode;
+  return slot;
+}
+
+/* Return true if X contains a VALUE rtx.  If ONLY_USELESS is set, we
+   only return true for values which point to a cselib_val whose value
+   element has been set to zero, which implies the cselib_val will be
+   removed.  */
+
+int
+references_value_p (const_rtx x, int only_useless)
+{
+  const enum rtx_code code = GET_CODE (x);
+  const char *fmt = GET_RTX_FORMAT (code);
+  int i, j;
+
+  if (GET_CODE (x) == VALUE
+      && (! only_useless ||
+	  (CSELIB_VAL_PTR (x)->locs == 0 && !PRESERVED_VALUE_P (x))))
+    return 1;
+
+  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
+    {
+      if (fmt[i] == 'e' && references_value_p (XEXP (x, i), only_useless))
+	return 1;
+      else if (fmt[i] == 'E')
+	for (j = 0; j < XVECLEN (x, i); j++)
+	  if (references_value_p (XVECEXP (x, i, j), only_useless))
+	    return 1;
+    }
+
+  return 0;
+}
+
+/* For all locations found in X, delete locations that reference useless
+   values (i.e. values without any location).  Called through
+   htab_traverse.  */
+
+int
+discard_useless_locs (cselib_val **x, void *info ATTRIBUTE_UNUSED)
+{
+  cselib_val *v = *x;
+  struct elt_loc_list **p = &v->locs;
+  bool had_locs = v->locs != NULL;
+  rtx setting_insn = v->locs ? v->locs->setting_insn : NULL;
+
+  while (*p)
+    {
+      if (references_value_p ((*p)->loc, 1))
+	unchain_one_elt_loc_list (p);
+      else
+	p = &(*p)->next;
+    }
+
+  if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
+    {
+      if (setting_insn && DEBUG_INSN_P (setting_insn))
+	n_useless_debug_values++;
+      else
+	n_useless_values++;
+      values_became_useless = 1;
+    }
+  return 1;
+}
+
+/* If X is a value with no locations, remove it from the hashtable.  */
+
+int
+discard_useless_values (cselib_val **x, void *info ATTRIBUTE_UNUSED)
+{
+  cselib_val *v = *x;
+
+  if (v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
+    {
+      if (cselib_discard_hook)
+	cselib_discard_hook (v);
+
+      CSELIB_VAL_PTR (v->val_rtx) = NULL;
+      cselib_hash_table.clear_slot (x);
+      unchain_one_value (v);
+      n_useless_values--;
+    }
+
+  return 1;
+}
+
+/* Clean out useless values (i.e. those which no longer have locations
+   associated with them) from the hash table.  */
+
+static void
+remove_useless_values (void)
+{
+  cselib_val **p, *v;
+
+  /* First pass: eliminate locations that reference the value.  That in
+     turn can make more values useless.  */
+  do
+    {
+      values_became_useless = 0;
+      cselib_hash_table.traverse <void *, discard_useless_locs> (NULL);
+    }
+  while (values_became_useless);
+
+  /* Second pass: actually remove the values.  */
+
+  p = &first_containing_mem;
+  for (v = *p; v != &dummy_val; v = v->next_containing_mem)
+    if (v->locs && v == canonical_cselib_val (v))
+      {
+	*p = v;
+	p = &(*p)->next_containing_mem;
+      }
+  *p = &dummy_val;
+
+  n_useless_values += n_useless_debug_values;
+  n_debug_values -= n_useless_debug_values;
+  n_useless_debug_values = 0;
+
+  cselib_hash_table.traverse <void *, discard_useless_values> (NULL);
+
+  gcc_assert (!n_useless_values);
+}
+
+/* Arrange for a value to not be removed from the hash table even if
+   it becomes useless.  */
+
+void
+cselib_preserve_value (cselib_val *v)
+{
+  PRESERVED_VALUE_P (v->val_rtx) = 1;
+}
+
+/* Test whether a value is preserved.  */
+
+bool
+cselib_preserved_value_p (cselib_val *v)
+{
+  return PRESERVED_VALUE_P (v->val_rtx);
+}
+
+/* Arrange for a REG value to be assumed constant through the whole function,
+   never invalidated and preserved across cselib_reset_table calls.  */
+
+void
+cselib_preserve_cfa_base_value (cselib_val *v, unsigned int regno)
+{
+  if (cselib_preserve_constants
+      && v->locs
+      && REG_P (v->locs->loc))
+    {
+      cfa_base_preserved_val = v;
+      cfa_base_preserved_regno = regno;
+    }
+}
+
+/* Clean all non-constant expressions in the hash table, but retain
+   their values.  */
+
+void
+cselib_preserve_only_values (void)
+{
+  int i;
+
+  for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+    cselib_invalidate_regno (i, reg_raw_mode[i]);
+
+  cselib_invalidate_mem (callmem);
+
+  remove_useless_values ();
+
+  gcc_assert (first_containing_mem == &dummy_val);
+}
+
+/* Arrange for a value to be marked as based on stack pointer
+   for find_base_term purposes.  */
+
+void
+cselib_set_value_sp_based (cselib_val *v)
+{
+  SP_BASED_VALUE_P (v->val_rtx) = 1;
+}
+
+/* Test whether a value is based on stack pointer for
+   find_base_term purposes.  */
+
+bool
+cselib_sp_based_value_p (cselib_val *v)
+{
+  return SP_BASED_VALUE_P (v->val_rtx);
+}
+
+/* Return the mode in which a register was last set.  If X is not a
+   register, return its mode.  If the mode in which the register was
+   set is not known, or the value was already clobbered, return
+   VOIDmode.  */
+
+enum machine_mode
+cselib_reg_set_mode (const_rtx x)
+{
+  if (!REG_P (x))
+    return GET_MODE (x);
+
+  if (REG_VALUES (REGNO (x)) == NULL
+      || REG_VALUES (REGNO (x))->elt == NULL)
+    return VOIDmode;
+
+  return GET_MODE (REG_VALUES (REGNO (x))->elt->val_rtx);
+}
+
+/* Return nonzero if we can prove that X and Y contain the same value, taking
+   our gathered information into account.  */
+
+int
+rtx_equal_for_cselib_p (rtx x, rtx y)
+{
+  return rtx_equal_for_cselib_1 (x, y, VOIDmode);
+}
+
+/* If x is a PLUS or an autoinc operation, expand the operation,
+   storing the offset, if any, in *OFF.  */
+
+static rtx
+autoinc_split (rtx x, rtx *off, enum machine_mode memmode)
+{
+  switch (GET_CODE (x))
+    {
+    case PLUS:
+      *off = XEXP (x, 1);
+      return XEXP (x, 0);
+
+    case PRE_DEC:
+      if (memmode == VOIDmode)
+	return x;
+
+      *off = GEN_INT (-GET_MODE_SIZE (memmode));
+      return XEXP (x, 0);
+      break;
+
+    case PRE_INC:
+      if (memmode == VOIDmode)
+	return x;
+
+      *off = GEN_INT (GET_MODE_SIZE (memmode));
+      return XEXP (x, 0);
+
+    case PRE_MODIFY:
+      return XEXP (x, 1);
+
+    case POST_DEC:
+    case POST_INC:
+    case POST_MODIFY:
+      return XEXP (x, 0);
+
+    default:
+      return x;
+    }
+}
+
+/* Return nonzero if we can prove that X and Y contain the same value,
+   taking our gathered information into account.  MEMMODE holds the
+   mode of the enclosing MEM, if any, as required to deal with autoinc
+   addressing modes.  If X and Y are not (known to be) part of
+   addresses, MEMMODE should be VOIDmode.  */
+
+static int
+rtx_equal_for_cselib_1 (rtx x, rtx y, enum machine_mode memmode)
+{
+  enum rtx_code code;
+  const char *fmt;
+  int i;
+
+  if (REG_P (x) || MEM_P (x))
+    {
+      cselib_val *e = cselib_lookup (x, GET_MODE (x), 0, memmode);
+
+      if (e)
+	x = e->val_rtx;
+    }
+
+  if (REG_P (y) || MEM_P (y))
+    {
+      cselib_val *e = cselib_lookup (y, GET_MODE (y), 0, memmode);
+
+      if (e)
+	y = e->val_rtx;
+    }
+
+  if (x == y)
+    return 1;
+
+  if (GET_CODE (x) == VALUE)
+    {
+      cselib_val *e = canonical_cselib_val (CSELIB_VAL_PTR (x));
+      struct elt_loc_list *l;
+
+      if (GET_CODE (y) == VALUE)
+	return e == canonical_cselib_val (CSELIB_VAL_PTR (y));
+
+      for (l = e->locs; l; l = l->next)
+	{
+	  rtx t = l->loc;
+
+	  /* Avoid infinite recursion.  We know we have the canonical
+	     value, so we can just skip any values in the equivalence
+	     list.  */
+	  if (REG_P (t) || MEM_P (t) || GET_CODE (t) == VALUE)
+	    continue;
+	  else if (rtx_equal_for_cselib_1 (t, y, memmode))
+	    return 1;
+	}
+
+      return 0;
+    }
+  else if (GET_CODE (y) == VALUE)
+    {
+      cselib_val *e = canonical_cselib_val (CSELIB_VAL_PTR (y));
+      struct elt_loc_list *l;
+
+      for (l = e->locs; l; l = l->next)
+	{
+	  rtx t = l->loc;
+
+	  if (REG_P (t) || MEM_P (t) || GET_CODE (t) == VALUE)
+	    continue;
+	  else if (rtx_equal_for_cselib_1 (x, t, memmode))
+	    return 1;
+	}
+
+      return 0;
+    }
+
+  if (GET_MODE (x) != GET_MODE (y))
+    return 0;
+
+  if (GET_CODE (x) != GET_CODE (y))
+    {
+      rtx xorig = x, yorig = y;
+      rtx xoff = NULL, yoff = NULL;
+
+      x = autoinc_split (x, &xoff, memmode);
+      y = autoinc_split (y, &yoff, memmode);
+
+      if (!xoff != !yoff)
+	return 0;
+
+      if (xoff && !rtx_equal_for_cselib_1 (xoff, yoff, memmode))
+	return 0;
+
+      /* Don't recurse if nothing changed.  */
+      if (x != xorig || y != yorig)
+	return rtx_equal_for_cselib_1 (x, y, memmode);
+
+      return 0;
+    }
+
+  /* These won't be handled correctly by the code below.  */
+  switch (GET_CODE (x))
+    {
+    case CONST_DOUBLE:
+    case CONST_FIXED:
+    case DEBUG_EXPR:
+      return 0;
+
+    case DEBUG_IMPLICIT_PTR:
+      return DEBUG_IMPLICIT_PTR_DECL (x)
+	     == DEBUG_IMPLICIT_PTR_DECL (y);
+
+    case DEBUG_PARAMETER_REF:
+      return DEBUG_PARAMETER_REF_DECL (x)
+	     == DEBUG_PARAMETER_REF_DECL (y);
+
+    case ENTRY_VALUE:
+      /* ENTRY_VALUEs are function invariant, it is thus undesirable to
+	 use rtx_equal_for_cselib_1 to compare the operands.  */
+      return rtx_equal_p (ENTRY_VALUE_EXP (x), ENTRY_VALUE_EXP (y));
+
+    case LABEL_REF:
+      return XEXP (x, 0) == XEXP (y, 0);
+
+    case MEM:
+      /* We have to compare any autoinc operations in the addresses
+	 using this MEM's mode.  */
+      return rtx_equal_for_cselib_1 (XEXP (x, 0), XEXP (y, 0), GET_MODE (x));
+
+    default:
+      break;
+    }
+
+  code = GET_CODE (x);
+  fmt = GET_RTX_FORMAT (code);
+
+  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
+    {
+      int j;
+
+      switch (fmt[i])
+	{
+	case 'w':
+	  if (XWINT (x, i) != XWINT (y, i))
+	    return 0;
+	  break;
+
+	case 'n':
+	case 'i':
+	  if (XINT (x, i) != XINT (y, i))
+	    return 0;
+	  break;
+
+	case 'V':
+	case 'E':
+	  /* Two vectors must have the same length.  */
+	  if (XVECLEN (x, i) != XVECLEN (y, i))
+	    return 0;
+
+	  /* And the corresponding elements must match.  */
+	  for (j = 0; j < XVECLEN (x, i); j++)
+	    if (! rtx_equal_for_cselib_1 (XVECEXP (x, i, j),
+					  XVECEXP (y, i, j), memmode))
+	      return 0;
+	  break;
+
+	case 'e':
+	  if (i == 1
+	      && targetm.commutative_p (x, UNKNOWN)
+	      && rtx_equal_for_cselib_1 (XEXP (x, 1), XEXP (y, 0), memmode)
+	      && rtx_equal_for_cselib_1 (XEXP (x, 0), XEXP (y, 1), memmode))
+	    return 1;
+	  if (! rtx_equal_for_cselib_1 (XEXP (x, i), XEXP (y, i), memmode))
+	    return 0;
+	  break;
+
+	case 'S':
+	case 's':
+	  if (strcmp (XSTR (x, i), XSTR (y, i)))
+	    return 0;
+	  break;
+
+	case 'u':
+	  /* These are just backpointers, so they don't matter.  */
+	  break;
+
+	case '0':
+	case 't':
+	  break;
+
+	  /* It is believed that rtx's at this level will never
+	     contain anything but integers and other rtx's,
+	     except for within LABEL_REFs and SYMBOL_REFs.  */
+	default:
+	  gcc_unreachable ();
+	}
+    }
+  return 1;
+}
+
+/* We need to pass down the mode of constants through the hash table
+   functions.  For that purpose, wrap them in a CONST of the appropriate
+   mode.  */
+static rtx
+wrap_constant (enum machine_mode mode, rtx x)
+{
+  if (!CONST_SCALAR_INT_P (x) && GET_CODE (x) != CONST_FIXED)
+    return x;
+  gcc_assert (mode != VOIDmode);
+  return gen_rtx_CONST (mode, x);
+}
+
+/* Hash an rtx.  Return 0 if we couldn't hash the rtx.
+   For registers and memory locations, we look up their cselib_val structure
+   and return its VALUE element.
+   Possible reasons for return 0 are: the object is volatile, or we couldn't
+   find a register or memory location in the table and CREATE is zero.  If
+   CREATE is nonzero, table elts are created for regs and mem.
+   N.B. this hash function returns the same hash value for RTXes that
+   differ only in the order of operands, thus it is suitable for comparisons
+   that take commutativity into account.
+   If we wanted to also support associative rules, we'd have to use a different
+   strategy to avoid returning spurious 0, e.g. return ~(~0U >> 1) .
+   MEMMODE indicates the mode of an enclosing MEM, and it's only
+   used to compute autoinc values.
+   We used to have a MODE argument for hashing for CONST_INTs, but that
+   didn't make sense, since it caused spurious hash differences between
+    (set (reg:SI 1) (const_int))
+    (plus:SI (reg:SI 2) (reg:SI 1))
+   and
+    (plus:SI (reg:SI 2) (const_int))
+   If the mode is important in any context, it must be checked specifically
+   in a comparison anyway, since relying on hash differences is unsafe.  */
+
+static unsigned int
+cselib_hash_rtx (rtx x, int create, enum machine_mode memmode)
+{
+  cselib_val *e;
+  int i, j;
+  enum rtx_code code;
+  const char *fmt;
+  unsigned int hash = 0;
+
+  code = GET_CODE (x);
+  hash += (unsigned) code + (unsigned) GET_MODE (x);
+
+  switch (code)
+    {
+    case VALUE:
+      e = CSELIB_VAL_PTR (x);
+      return e->hash;
+
+    case MEM:
+    case REG:
+      e = cselib_lookup (x, GET_MODE (x), create, memmode);
+      if (! e)
+	return 0;
+
+      return e->hash;
+
+    case DEBUG_EXPR:
+      hash += ((unsigned) DEBUG_EXPR << 7)
+	      + DEBUG_TEMP_UID (DEBUG_EXPR_TREE_DECL (x));
+      return hash ? hash : (unsigned int) DEBUG_EXPR;
+
+    case DEBUG_IMPLICIT_PTR:
+      hash += ((unsigned) DEBUG_IMPLICIT_PTR << 7)
+	      + DECL_UID (DEBUG_IMPLICIT_PTR_DECL (x));
+      return hash ? hash : (unsigned int) DEBUG_IMPLICIT_PTR;
+
+    case DEBUG_PARAMETER_REF:
+      hash += ((unsigned) DEBUG_PARAMETER_REF << 7)
+	      + DECL_UID (DEBUG_PARAMETER_REF_DECL (x));
+      return hash ? hash : (unsigned int) DEBUG_PARAMETER_REF;
+
+    case ENTRY_VALUE:
+      /* ENTRY_VALUEs are function invariant, thus try to avoid
+	 recursing on argument if ENTRY_VALUE is one of the
+	 forms emitted by expand_debug_expr, otherwise
+	 ENTRY_VALUE hash would depend on the current value
+	 in some register or memory.  */
+      if (REG_P (ENTRY_VALUE_EXP (x)))
+	hash += (unsigned int) REG
+		+ (unsigned int) GET_MODE (ENTRY_VALUE_EXP (x))
+		+ (unsigned int) REGNO (ENTRY_VALUE_EXP (x));
+      else if (MEM_P (ENTRY_VALUE_EXP (x))
+	       && REG_P (XEXP (ENTRY_VALUE_EXP (x), 0)))
+	hash += (unsigned int) MEM
+		+ (unsigned int) GET_MODE (XEXP (ENTRY_VALUE_EXP (x), 0))
+		+ (unsigned int) REGNO (XEXP (ENTRY_VALUE_EXP (x), 0));
+      else
+	hash += cselib_hash_rtx (ENTRY_VALUE_EXP (x), create, memmode);
+      return hash ? hash : (unsigned int) ENTRY_VALUE;
+
+    case CONST_INT:
+      hash += ((unsigned) CONST_INT << 7) + INTVAL (x);
+      return hash ? hash : (unsigned int) CONST_INT;
+
+    case CONST_DOUBLE:
+      /* This is like the general case, except that it only counts
+	 the integers representing the constant.  */
+      hash += (unsigned) code + (unsigned) GET_MODE (x);
+      if (GET_MODE (x) != VOIDmode)
+	hash += real_hash (CONST_DOUBLE_REAL_VALUE (x));
+      else
+	hash += ((unsigned) CONST_DOUBLE_LOW (x)
+		 + (unsigned) CONST_DOUBLE_HIGH (x));
+      return hash ? hash : (unsigned int) CONST_DOUBLE;
+
+    case CONST_FIXED:
+      hash += (unsigned int) code + (unsigned int) GET_MODE (x);
+      hash += fixed_hash (CONST_FIXED_VALUE (x));
+      return hash ? hash : (unsigned int) CONST_FIXED;
+
+    case CONST_VECTOR:
+      {
+	int units;
+	rtx elt;
+
+	units = CONST_VECTOR_NUNITS (x);
+
+	for (i = 0; i < units; ++i)
+	  {
+	    elt = CONST_VECTOR_ELT (x, i);
+	    hash += cselib_hash_rtx (elt, 0, memmode);
+	  }
+
+	return hash;
+      }
+
+      /* Assume there is only one rtx object for any given label.  */
+    case LABEL_REF:
+      /* We don't hash on the address of the CODE_LABEL to avoid bootstrap
+	 differences and differences between each stage's debugging dumps.  */
+      hash += (((unsigned int) LABEL_REF << 7)
+	       + CODE_LABEL_NUMBER (XEXP (x, 0)));
+      return hash ? hash : (unsigned int) LABEL_REF;
+
+    case SYMBOL_REF:
+      {
+	/* Don't hash on the symbol's address to avoid bootstrap differences.
+	   Different hash values may cause expressions to be recorded in
+	   different orders and thus different registers to be used in the
+	   final assembler.  This also avoids differences in the dump files
+	   between various stages.  */
+	unsigned int h = 0;
+	const unsigned char *p = (const unsigned char *) XSTR (x, 0);
+
+	while (*p)
+	  h += (h << 7) + *p++; /* ??? revisit */
+
+	hash += ((unsigned int) SYMBOL_REF << 7) + h;
+	return hash ? hash : (unsigned int) SYMBOL_REF;
+      }
+
+    case PRE_DEC:
+    case PRE_INC:
+      /* We can't compute these without knowing the MEM mode.  */
+      gcc_assert (memmode != VOIDmode);
+      i = GET_MODE_SIZE (memmode);
+      if (code == PRE_DEC)
+	i = -i;
+      /* Adjust the hash so that (mem:MEMMODE (pre_* (reg))) hashes
+	 like (mem:MEMMODE (plus (reg) (const_int I))).  */
+      hash += (unsigned) PLUS - (unsigned)code
+	+ cselib_hash_rtx (XEXP (x, 0), create, memmode)
+	+ cselib_hash_rtx (GEN_INT (i), create, memmode);
+      return hash ? hash : 1 + (unsigned) PLUS;
+
+    case PRE_MODIFY:
+      gcc_assert (memmode != VOIDmode);
+      return cselib_hash_rtx (XEXP (x, 1), create, memmode);
+
+    case POST_DEC:
+    case POST_INC:
+    case POST_MODIFY:
+      gcc_assert (memmode != VOIDmode);
+      return cselib_hash_rtx (XEXP (x, 0), create, memmode);
+
+    case PC:
+    case CC0:
+    case CALL:
+    case UNSPEC_VOLATILE:
+      return 0;
+
+    case ASM_OPERANDS:
+      if (MEM_VOLATILE_P (x))
+	return 0;
+
+      break;
+
+    default:
+      break;
+    }
+
+  i = GET_RTX_LENGTH (code) - 1;
+  fmt = GET_RTX_FORMAT (code);
+  for (; i >= 0; i--)
+    {
+      switch (fmt[i])
+	{
+	case 'e':
+	  {
+	    rtx tem = XEXP (x, i);
+	    unsigned int tem_hash = cselib_hash_rtx (tem, create, memmode);
+
+	    if (tem_hash == 0)
+	      return 0;
+
+	    hash += tem_hash;
+	  }
+	  break;
+	case 'E':
+	  for (j = 0; j < XVECLEN (x, i); j++)
+	    {
+	      unsigned int tem_hash
+		= cselib_hash_rtx (XVECEXP (x, i, j), create, memmode);
+
+	      if (tem_hash == 0)
+		return 0;
+
+	      hash += tem_hash;
+	    }
+	  break;
+
+	case 's':
+	  {
+	    const unsigned char *p = (const unsigned char *) XSTR (x, i);
+
+	    if (p)
+	      while (*p)
+		hash += *p++;
+	    break;
+	  }
+
+	case 'i':
+	  hash += XINT (x, i);
+	  break;
+
+	case '0':
+	case 't':
+	  /* unused */
+	  break;
+
+	default:
+	  gcc_unreachable ();
+	}
+    }
+
+  return hash ? hash : 1 + (unsigned int) GET_CODE (x);
+}
+
+/* Create a new value structure for VALUE and initialize it.  The mode of the
+   value is MODE.  */
+
+static inline cselib_val *
+new_cselib_val (unsigned int hash, enum machine_mode mode, rtx x)
+{
+  cselib_val *e = (cselib_val *) pool_alloc (cselib_val_pool);
+
+  gcc_assert (hash);
+  gcc_assert (next_uid);
+
+  e->hash = hash;
+  e->uid = next_uid++;
+  /* We use an alloc pool to allocate this RTL construct because it
+     accounts for about 8% of the overall memory usage.  We know
+     precisely when we can have VALUE RTXen (when cselib is active)
+     so we don't need to put them in garbage collected memory.
+     ??? Why should a VALUE be an RTX in the first place?  */
+  e->val_rtx = (rtx) pool_alloc (value_pool);
+  memset (e->val_rtx, 0, RTX_HDR_SIZE);
+  PUT_CODE (e->val_rtx, VALUE);
+  PUT_MODE (e->val_rtx, mode);
+  CSELIB_VAL_PTR (e->val_rtx) = e;
+  e->addr_list = 0;
+  e->locs = 0;
+  e->next_containing_mem = 0;
+
+  if (dump_file && (dump_flags & TDF_CSELIB))
+    {
+      fprintf (dump_file, "cselib value %u:%u ", e->uid, hash);
+      if (flag_dump_noaddr || flag_dump_unnumbered)
+	fputs ("# ", dump_file);
+      else
+	fprintf (dump_file, "%p ", (void*)e);
+      print_rtl_single (dump_file, x);
+      fputc ('\n', dump_file);
+    }
+
+  return e;
+}
+
+/* ADDR_ELT is a value that is used as address.  MEM_ELT is the value that
+   contains the data at this address.  X is a MEM that represents the
+   value.  Update the two value structures to represent this situation.  */
+
+static void
+add_mem_for_addr (cselib_val *addr_elt, cselib_val *mem_elt, rtx x)
+{
+  struct elt_loc_list *l;
+
+  addr_elt = canonical_cselib_val (addr_elt);
+  mem_elt = canonical_cselib_val (mem_elt);
+
+  /* Avoid duplicates.  */
+  for (l = mem_elt->locs; l; l = l->next)
+    if (MEM_P (l->loc)
+	&& CSELIB_VAL_PTR (XEXP (l->loc, 0)) == addr_elt)
+      {
+	promote_debug_loc (l);
+	return;
+      }
+
+  addr_elt->addr_list = new_elt_list (addr_elt->addr_list, mem_elt);
+  new_elt_loc_list (mem_elt,
+		    replace_equiv_address_nv (x, addr_elt->val_rtx));
+  if (mem_elt->next_containing_mem == NULL)
+    {
+      mem_elt->next_containing_mem = first_containing_mem;
+      first_containing_mem = mem_elt;
+    }
+}
+
+/* Subroutine of cselib_lookup.  Return a value for X, which is a MEM rtx.
+   If CREATE, make a new one if we haven't seen it before.  */
+
+static cselib_val *
+cselib_lookup_mem (rtx x, int create)
+{
+  enum machine_mode mode = GET_MODE (x);
+  enum machine_mode addr_mode;
+  cselib_val **slot;
+  cselib_val *addr;
+  cselib_val *mem_elt;
+  struct elt_list *l;
+
+  if (MEM_VOLATILE_P (x) || mode == BLKmode
+      || !cselib_record_memory
+      || (FLOAT_MODE_P (mode) && flag_float_store))
+    return 0;
+
+  addr_mode = GET_MODE (XEXP (x, 0));
+  if (addr_mode == VOIDmode)
+    addr_mode = Pmode;
+
+  /* Look up the value for the address.  */
+  addr = cselib_lookup (XEXP (x, 0), addr_mode, create, mode);
+  if (! addr)
+    return 0;
+
+  addr = canonical_cselib_val (addr);
+  /* Find a value that describes a value of our mode at that address.  */
+  for (l = addr->addr_list; l; l = l->next)
+    if (GET_MODE (l->elt->val_rtx) == mode)
+      {
+	promote_debug_loc (l->elt->locs);
+	return l->elt;
+      }
+
+  if (! create)
+    return 0;
+
+  mem_elt = new_cselib_val (next_uid, mode, x);
+  add_mem_for_addr (addr, mem_elt, x);
+  slot = cselib_find_slot (wrap_constant (mode, x), mem_elt->hash,
+			   INSERT, mode);
+  *slot = mem_elt;
+  return mem_elt;
+}
+
+/* Search through the possible substitutions in P.  We prefer a non reg
+   substitution because this allows us to expand the tree further.  If
+   we find, just a reg, take the lowest regno.  There may be several
+   non-reg results, we just take the first one because they will all
+   expand to the same place.  */
+
+static rtx
+expand_loc (struct elt_loc_list *p, struct expand_value_data *evd,
+	    int max_depth)
+{
+  rtx reg_result = NULL;
+  unsigned int regno = UINT_MAX;
+  struct elt_loc_list *p_in = p;
+
+  for (; p; p = p->next)
+    {
+      /* Return these right away to avoid returning stack pointer based
+	 expressions for frame pointer and vice versa, which is something
+	 that would confuse DSE.  See the comment in cselib_expand_value_rtx_1
+	 for more details.  */
+      if (REG_P (p->loc)
+	  && (REGNO (p->loc) == STACK_POINTER_REGNUM
+	      || REGNO (p->loc) == FRAME_POINTER_REGNUM
+	      || REGNO (p->loc) == HARD_FRAME_POINTER_REGNUM
+	      || REGNO (p->loc) == cfa_base_preserved_regno))
+	return p->loc;
+      /* Avoid infinite recursion trying to expand a reg into a
+	 the same reg.  */
+      if ((REG_P (p->loc))
+	  && (REGNO (p->loc) < regno)
+	  && !bitmap_bit_p (evd->regs_active, REGNO (p->loc)))
+	{
+	  reg_result = p->loc;
+	  regno = REGNO (p->loc);
+	}
+      /* Avoid infinite recursion and do not try to expand the
+	 value.  */
+      else if (GET_CODE (p->loc) == VALUE
+	       && CSELIB_VAL_PTR (p->loc)->locs == p_in)
+	continue;
+      else if (!REG_P (p->loc))
+	{
+	  rtx result, note;
+	  if (dump_file && (dump_flags & TDF_CSELIB))
+	    {
+	      print_inline_rtx (dump_file, p->loc, 0);
+	      fprintf (dump_file, "\n");
+	    }
+	  if (GET_CODE (p->loc) == LO_SUM
+	      && GET_CODE (XEXP (p->loc, 1)) == SYMBOL_REF
+	      && p->setting_insn
+	      && (note = find_reg_note (p->setting_insn, REG_EQUAL, NULL_RTX))
+	      && XEXP (note, 0) == XEXP (p->loc, 1))
+	    return XEXP (p->loc, 1);
+	  result = cselib_expand_value_rtx_1 (p->loc, evd, max_depth - 1);
+	  if (result)
+	    return result;
+	}
+
+    }
+
+  if (regno != UINT_MAX)
+    {
+      rtx result;
+      if (dump_file && (dump_flags & TDF_CSELIB))
+	fprintf (dump_file, "r%d\n", regno);
+
+      result = cselib_expand_value_rtx_1 (reg_result, evd, max_depth - 1);
+      if (result)
+	return result;
+    }
+
+  if (dump_file && (dump_flags & TDF_CSELIB))
+    {
+      if (reg_result)
+	{
+	  print_inline_rtx (dump_file, reg_result, 0);
+	  fprintf (dump_file, "\n");
+	}
+      else
+	fprintf (dump_file, "NULL\n");
+    }
+  return reg_result;
+}
+
+
+/* Forward substitute and expand an expression out to its roots.
+   This is the opposite of common subexpression.  Because local value
+   numbering is such a weak optimization, the expanded expression is
+   pretty much unique (not from a pointer equals point of view but
+   from a tree shape point of view.
+
+   This function returns NULL if the expansion fails.  The expansion
+   will fail if there is no value number for one of the operands or if
+   one of the operands has been overwritten between the current insn
+   and the beginning of the basic block.  For instance x has no
+   expansion in:
+
+   r1 <- r1 + 3
+   x <- r1 + 8
+
+   REGS_ACTIVE is a scratch bitmap that should be clear when passing in.
+   It is clear on return.  */
+
+rtx
+cselib_expand_value_rtx (rtx orig, bitmap regs_active, int max_depth)
+{
+  struct expand_value_data evd;
+
+  evd.regs_active = regs_active;
+  evd.callback = NULL;
+  evd.callback_arg = NULL;
+  evd.dummy = false;
+
+  return cselib_expand_value_rtx_1 (orig, &evd, max_depth);
+}
+
+/* Same as cselib_expand_value_rtx, but using a callback to try to
+   resolve some expressions.  The CB function should return ORIG if it
+   can't or does not want to deal with a certain RTX.  Any other
+   return value, including NULL, will be used as the expansion for
+   VALUE, without any further changes.  */
+
+rtx
+cselib_expand_value_rtx_cb (rtx orig, bitmap regs_active, int max_depth,
+			    cselib_expand_callback cb, void *data)
+{
+  struct expand_value_data evd;
+
+  evd.regs_active = regs_active;
+  evd.callback = cb;
+  evd.callback_arg = data;
+  evd.dummy = false;
+
+  return cselib_expand_value_rtx_1 (orig, &evd, max_depth);
+}
+
+/* Similar to cselib_expand_value_rtx_cb, but no rtxs are actually copied
+   or simplified.  Useful to find out whether cselib_expand_value_rtx_cb
+   would return NULL or non-NULL, without allocating new rtx.  */
+
+bool
+cselib_dummy_expand_value_rtx_cb (rtx orig, bitmap regs_active, int max_depth,
+				  cselib_expand_callback cb, void *data)
+{
+  struct expand_value_data evd;
+
+  evd.regs_active = regs_active;
+  evd.callback = cb;
+  evd.callback_arg = data;
+  evd.dummy = true;
+
+  return cselib_expand_value_rtx_1 (orig, &evd, max_depth) != NULL;
+}
+
+/* Internal implementation of cselib_expand_value_rtx and
+   cselib_expand_value_rtx_cb.  */
+
+static rtx
+cselib_expand_value_rtx_1 (rtx orig, struct expand_value_data *evd,
+			   int max_depth)
+{
+  rtx copy, scopy;
+  int i, j;
+  RTX_CODE code;
+  const char *format_ptr;
+  enum machine_mode mode;
+
+  code = GET_CODE (orig);
+
+  /* For the context of dse, if we end up expand into a huge tree, we
+     will not have a useful address, so we might as well just give up
+     quickly.  */
+  if (max_depth <= 0)
+    return NULL;
+
+  switch (code)
+    {
+    case REG:
+      {
+	struct elt_list *l = REG_VALUES (REGNO (orig));
+
+	if (l && l->elt == NULL)
+	  l = l->next;
+	for (; l; l = l->next)
+	  if (GET_MODE (l->elt->val_rtx) == GET_MODE (orig))
+	    {
+	      rtx result;
+	      unsigned regno = REGNO (orig);
+
+	      /* The only thing that we are not willing to do (this
+		 is requirement of dse and if others potential uses
+		 need this function we should add a parm to control
+		 it) is that we will not substitute the
+		 STACK_POINTER_REGNUM, FRAME_POINTER or the
+		 HARD_FRAME_POINTER.
+
+		 These expansions confuses the code that notices that
+		 stores into the frame go dead at the end of the
+		 function and that the frame is not effected by calls
+		 to subroutines.  If you allow the
+		 STACK_POINTER_REGNUM substitution, then dse will
+		 think that parameter pushing also goes dead which is
+		 wrong.  If you allow the FRAME_POINTER or the
+		 HARD_FRAME_POINTER then you lose the opportunity to
+		 make the frame assumptions.  */
+	      if (regno == STACK_POINTER_REGNUM
+		  || regno == FRAME_POINTER_REGNUM
+		  || regno == HARD_FRAME_POINTER_REGNUM
+		  || regno == cfa_base_preserved_regno)
+		return orig;
+
+	      bitmap_set_bit (evd->regs_active, regno);
+
+	      if (dump_file && (dump_flags & TDF_CSELIB))
+		fprintf (dump_file, "expanding: r%d into: ", regno);
+
+	      result = expand_loc (l->elt->locs, evd, max_depth);
+	      bitmap_clear_bit (evd->regs_active, regno);
+
+	      if (result)
+		return result;
+	      else
+		return orig;
+	    }
+      }
+
+    CASE_CONST_ANY:
+    case SYMBOL_REF:
+    case CODE_LABEL:
+    case PC:
+    case CC0:
+    case SCRATCH:
+      /* SCRATCH must be shared because they represent distinct values.  */
+      return orig;
+    case CLOBBER:
+      if (REG_P (XEXP (orig, 0)) && HARD_REGISTER_NUM_P (REGNO (XEXP (orig, 0))))
+	return orig;
+      break;
+
+    case CONST:
+      if (shared_const_p (orig))
+	return orig;
+      break;
+
+    case SUBREG:
+      {
+	rtx subreg;
+
+	if (evd->callback)
+	  {
+	    subreg = evd->callback (orig, evd->regs_active, max_depth,
+				    evd->callback_arg);
+	    if (subreg != orig)
+	      return subreg;
+	  }
+
+	subreg = cselib_expand_value_rtx_1 (SUBREG_REG (orig), evd,
+					    max_depth - 1);
+	if (!subreg)
+	  return NULL;
+	scopy = simplify_gen_subreg (GET_MODE (orig), subreg,
+				     GET_MODE (SUBREG_REG (orig)),
+				     SUBREG_BYTE (orig));
+	if (scopy == NULL
+	    || (GET_CODE (scopy) == SUBREG
+		&& !REG_P (SUBREG_REG (scopy))
+		&& !MEM_P (SUBREG_REG (scopy))))
+	  return NULL;
+
+	return scopy;
+      }
+
+    case VALUE:
+      {
+	rtx result;
+
+	if (dump_file && (dump_flags & TDF_CSELIB))
+	  {
+	    fputs ("\nexpanding ", dump_file);
+	    print_rtl_single (dump_file, orig);
+	    fputs (" into...", dump_file);
+	  }
+
+	if (evd->callback)
+	  {
+	    result = evd->callback (orig, evd->regs_active, max_depth,
+				    evd->callback_arg);
+
+	    if (result != orig)
+	      return result;
+	  }
+
+	result = expand_loc (CSELIB_VAL_PTR (orig)->locs, evd, max_depth);
+	return result;
+      }
+
+    case DEBUG_EXPR:
+      if (evd->callback)
+	return evd->callback (orig, evd->regs_active, max_depth,
+			      evd->callback_arg);
+      return orig;
+
+    default:
+      break;
+    }
+
+  /* Copy the various flags, fields, and other information.  We assume
+     that all fields need copying, and then clear the fields that should
+     not be copied.  That is the sensible default behavior, and forces
+     us to explicitly document why we are *not* copying a flag.  */
+  if (evd->dummy)
+    copy = NULL;
+  else
+    copy = shallow_copy_rtx (orig);
+
+  format_ptr = GET_RTX_FORMAT (code);
+
+  for (i = 0; i < GET_RTX_LENGTH (code); i++)
+    switch (*format_ptr++)
+      {
+      case 'e':
+	if (XEXP (orig, i) != NULL)
+	  {
+	    rtx result = cselib_expand_value_rtx_1 (XEXP (orig, i), evd,
+						    max_depth - 1);
+	    if (!result)
+	      return NULL;
+	    if (copy)
+	      XEXP (copy, i) = result;
+	  }
+	break;
+
+      case 'E':
+      case 'V':
+	if (XVEC (orig, i) != NULL)
+	  {
+	    if (copy)
+	      XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
+	    for (j = 0; j < XVECLEN (orig, i); j++)
+	      {
+		rtx result = cselib_expand_value_rtx_1 (XVECEXP (orig, i, j),
+							evd, max_depth - 1);
+		if (!result)
+		  return NULL;
+		if (copy)
+		  XVECEXP (copy, i, j) = result;
+	      }
+	  }
+	break;
+
+      case 't':
+      case 'w':
+      case 'i':
+      case 's':
+      case 'S':
+      case 'T':
+      case 'u':
+      case 'B':
+      case '0':
+	/* These are left unchanged.  */
+	break;
+
+      default:
+	gcc_unreachable ();
+      }
+
+  if (evd->dummy)
+    return orig;
+
+  mode = GET_MODE (copy);
+  /* If an operand has been simplified into CONST_INT, which doesn't
+     have a mode and the mode isn't derivable from whole rtx's mode,
+     try simplify_*_operation first with mode from original's operand
+     and as a fallback wrap CONST_INT into gen_rtx_CONST.  */
+  scopy = copy;
+  switch (GET_RTX_CLASS (code))
+    {
+    case RTX_UNARY:
+      if (CONST_INT_P (XEXP (copy, 0))
+	  && GET_MODE (XEXP (orig, 0)) != VOIDmode)
+	{
+	  scopy = simplify_unary_operation (code, mode, XEXP (copy, 0),
+					    GET_MODE (XEXP (orig, 0)));
+	  if (scopy)
+	    return scopy;
+	}
+      break;
+    case RTX_COMM_ARITH:
+    case RTX_BIN_ARITH:
+      /* These expressions can derive operand modes from the whole rtx's mode.  */
+      break;
+    case RTX_TERNARY:
+    case RTX_BITFIELD_OPS:
+      if (CONST_INT_P (XEXP (copy, 0))
+	  && GET_MODE (XEXP (orig, 0)) != VOIDmode)
+	{
+	  scopy = simplify_ternary_operation (code, mode,
+					      GET_MODE (XEXP (orig, 0)),
+					      XEXP (copy, 0), XEXP (copy, 1),
+					      XEXP (copy, 2));
+	  if (scopy)
+	    return scopy;
+	}
+      break;
+    case RTX_COMPARE:
+    case RTX_COMM_COMPARE:
+      if (CONST_INT_P (XEXP (copy, 0))
+	  && GET_MODE (XEXP (copy, 1)) == VOIDmode
+	  && (GET_MODE (XEXP (orig, 0)) != VOIDmode
+	      || GET_MODE (XEXP (orig, 1)) != VOIDmode))
+	{
+	  scopy = simplify_relational_operation (code, mode,
+						 (GET_MODE (XEXP (orig, 0))
+						  != VOIDmode)
+						 ? GET_MODE (XEXP (orig, 0))
+						 : GET_MODE (XEXP (orig, 1)),
+						 XEXP (copy, 0),
+						 XEXP (copy, 1));
+	  if (scopy)
+	    return scopy;
+	}
+      break;
+    default:
+      break;
+    }
+  scopy = simplify_rtx (copy);
+  if (scopy)
+    return scopy;
+  return copy;
+}
+
+/* Walk rtx X and replace all occurrences of REG and MEM subexpressions
+   with VALUE expressions.  This way, it becomes independent of changes
+   to registers and memory.
+   X isn't actually modified; if modifications are needed, new rtl is
+   allocated.  However, the return value can share rtl with X.
+   If X is within a MEM, MEMMODE must be the mode of the MEM.  */
+
+rtx
+cselib_subst_to_values (rtx x, enum machine_mode memmode)
+{
+  enum rtx_code code = GET_CODE (x);
+  const char *fmt = GET_RTX_FORMAT (code);
+  cselib_val *e;
+  struct elt_list *l;
+  rtx copy = x;
+  int i;
+
+  switch (code)
+    {
+    case REG:
+      l = REG_VALUES (REGNO (x));
+      if (l && l->elt == NULL)
+	l = l->next;
+      for (; l; l = l->next)
+	if (GET_MODE (l->elt->val_rtx) == GET_MODE (x))
+	  return l->elt->val_rtx;
+
+      gcc_unreachable ();
+
+    case MEM:
+      e = cselib_lookup_mem (x, 0);
+      /* This used to happen for autoincrements, but we deal with them
+	 properly now.  Remove the if stmt for the next release.  */
+      if (! e)
+	{
+	  /* Assign a value that doesn't match any other.  */
+	  e = new_cselib_val (next_uid, GET_MODE (x), x);
+	}
+      return e->val_rtx;
+
+    case ENTRY_VALUE:
+      e = cselib_lookup (x, GET_MODE (x), 0, memmode);
+      if (! e)
+	break;
+      return e->val_rtx;
+
+    CASE_CONST_ANY:
+      return x;
+
+    case PRE_DEC:
+    case PRE_INC:
+      gcc_assert (memmode != VOIDmode);
+      i = GET_MODE_SIZE (memmode);
+      if (code == PRE_DEC)
+	i = -i;
+      return cselib_subst_to_values (plus_constant (GET_MODE (x),
+						    XEXP (x, 0), i),
+				     memmode);
+
+    case PRE_MODIFY:
+      gcc_assert (memmode != VOIDmode);
+      return cselib_subst_to_values (XEXP (x, 1), memmode);
+
+    case POST_DEC:
+    case POST_INC:
+    case POST_MODIFY:
+      gcc_assert (memmode != VOIDmode);
+      return cselib_subst_to_values (XEXP (x, 0), memmode);
+
+    default:
+      break;
+    }
+
+  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
+    {
+      if (fmt[i] == 'e')
+	{
+	  rtx t = cselib_subst_to_values (XEXP (x, i), memmode);
+
+	  if (t != XEXP (x, i))
+	    {
+	      if (x == copy)
+		copy = shallow_copy_rtx (x);
+	      XEXP (copy, i) = t;
+	    }
+	}
+      else if (fmt[i] == 'E')
+	{
+	  int j;
+
+	  for (j = 0; j < XVECLEN (x, i); j++)
+	    {
+	      rtx t = cselib_subst_to_values (XVECEXP (x, i, j), memmode);
+
+	      if (t != XVECEXP (x, i, j))
+		{
+		  if (XVEC (x, i) == XVEC (copy, i))
+		    {
+		      if (x == copy)
+			copy = shallow_copy_rtx (x);
+		      XVEC (copy, i) = shallow_copy_rtvec (XVEC (x, i));
+		    }
+		  XVECEXP (copy, i, j) = t;
+		}
+	    }
+	}
+    }
+
+  return copy;
+}
+
+/* Wrapper for cselib_subst_to_values, that indicates X is in INSN.  */
+
+rtx
+cselib_subst_to_values_from_insn (rtx x, enum machine_mode memmode, rtx insn)
+{
+  rtx ret;
+  gcc_assert (!cselib_current_insn);
+  cselib_current_insn = insn;
+  ret = cselib_subst_to_values (x, memmode);
+  cselib_current_insn = NULL;
+  return ret;
+}
+
+/* Look up the rtl expression X in our tables and return the value it
+   has.  If CREATE is zero, we return NULL if we don't know the value.
+   Otherwise, we create a new one if possible, using mode MODE if X
+   doesn't have a mode (i.e. because it's a constant).  When X is part
+   of an address, MEMMODE should be the mode of the enclosing MEM if
+   we're tracking autoinc expressions.  */
+
+static cselib_val *
+cselib_lookup_1 (rtx x, enum machine_mode mode,
+		 int create, enum machine_mode memmode)
+{
+  cselib_val **slot;
+  cselib_val *e;
+  unsigned int hashval;
+
+  if (GET_MODE (x) != VOIDmode)
+    mode = GET_MODE (x);
+
+  if (GET_CODE (x) == VALUE)
+    return CSELIB_VAL_PTR (x);
+
+  if (REG_P (x))
+    {
+      struct elt_list *l;
+      unsigned int i = REGNO (x);
+
+      l = REG_VALUES (i);
+      if (l && l->elt == NULL)
+	l = l->next;
+      for (; l; l = l->next)
+	if (mode == GET_MODE (l->elt->val_rtx))
+	  {
+	    promote_debug_loc (l->elt->locs);
+	    return l->elt;
+	  }
+
+      if (! create)
+	return 0;
+
+      if (i < FIRST_PSEUDO_REGISTER)
+	{
+	  unsigned int n = hard_regno_nregs[i][mode];
+
+	  if (n > max_value_regs)
+	    max_value_regs = n;
+	}
+
+      e = new_cselib_val (next_uid, GET_MODE (x), x);
+      new_elt_loc_list (e, x);
+      if (REG_VALUES (i) == 0)
+	{
+	  /* Maintain the invariant that the first entry of
+	     REG_VALUES, if present, must be the value used to set the
+	     register, or NULL.  */
+	  used_regs[n_used_regs++] = i;
+	  REG_VALUES (i) = new_elt_list (REG_VALUES (i), NULL);
+	}
+      else if (cselib_preserve_constants
+	       && GET_MODE_CLASS (mode) == MODE_INT)
+	{
+	  /* During var-tracking, try harder to find equivalences
+	     for SUBREGs.  If a setter sets say a DImode register
+	     and user uses that register only in SImode, add a lowpart
+	     subreg location.  */
+	  struct elt_list *lwider = NULL;
+	  l = REG_VALUES (i);
+	  if (l && l->elt == NULL)
+	    l = l->next;
+	  for (; l; l = l->next)
+	    if (GET_MODE_CLASS (GET_MODE (l->elt->val_rtx)) == MODE_INT
+		&& GET_MODE_SIZE (GET_MODE (l->elt->val_rtx))
+		   > GET_MODE_SIZE (mode)
+		&& (lwider == NULL
+		    || GET_MODE_SIZE (GET_MODE (l->elt->val_rtx))
+		       < GET_MODE_SIZE (GET_MODE (lwider->elt->val_rtx))))
+	      {
+		struct elt_loc_list *el;
+		if (i < FIRST_PSEUDO_REGISTER
+		    && hard_regno_nregs[i][GET_MODE (l->elt->val_rtx)] != 1)
+		  continue;
+		for (el = l->elt->locs; el; el = el->next)
+		  if (!REG_P (el->loc))
+		    break;
+		if (el)
+		  lwider = l;
+	      }
+	  if (lwider)
+	    {
+	      rtx sub = lowpart_subreg (mode, lwider->elt->val_rtx,
+					GET_MODE (lwider->elt->val_rtx));
+	      if (sub)
+		new_elt_loc_list (e, sub);
+	    }
+	}
+      REG_VALUES (i)->next = new_elt_list (REG_VALUES (i)->next, e);
+      slot = cselib_find_slot (x, e->hash, INSERT, memmode);
+      *slot = e;
+      return e;
+    }
+
+  if (MEM_P (x))
+    return cselib_lookup_mem (x, create);
+
+  hashval = cselib_hash_rtx (x, create, memmode);
+  /* Can't even create if hashing is not possible.  */
+  if (! hashval)
+    return 0;
+
+  slot = cselib_find_slot (wrap_constant (mode, x), hashval,
+			   create ? INSERT : NO_INSERT, memmode);
+  if (slot == 0)
+    return 0;
+
+  e = (cselib_val *) *slot;
+  if (e)
+    return e;
+
+  e = new_cselib_val (hashval, mode, x);
+
+  /* We have to fill the slot before calling cselib_subst_to_values:
+     the hash table is inconsistent until we do so, and
+     cselib_subst_to_values will need to do lookups.  */
+  *slot = e;
+  new_elt_loc_list (e, cselib_subst_to_values (x, memmode));
+  return e;
+}
+
+/* Wrapper for cselib_lookup, that indicates X is in INSN.  */
+
+cselib_val *
+cselib_lookup_from_insn (rtx x, enum machine_mode mode,
+			 int create, enum machine_mode memmode, rtx insn)
+{
+  cselib_val *ret;
+
+  gcc_assert (!cselib_current_insn);
+  cselib_current_insn = insn;
+
+  ret = cselib_lookup (x, mode, create, memmode);
+
+  cselib_current_insn = NULL;
+
+  return ret;
+}
+
+/* Wrapper for cselib_lookup_1, that logs the lookup result and
+   maintains invariants related with debug insns.  */
+
+cselib_val *
+cselib_lookup (rtx x, enum machine_mode mode,
+	       int create, enum machine_mode memmode)
+{
+  cselib_val *ret = cselib_lookup_1 (x, mode, create, memmode);
+
+  /* ??? Should we return NULL if we're not to create an entry, the
+     found loc is a debug loc and cselib_current_insn is not DEBUG?
+     If so, we should also avoid converting val to non-DEBUG; probably
+     easiest setting cselib_current_insn to NULL before the call
+     above.  */
+
+  if (dump_file && (dump_flags & TDF_CSELIB))
+    {
+      fputs ("cselib lookup ", dump_file);
+      print_inline_rtx (dump_file, x, 2);
+      fprintf (dump_file, " => %u:%u\n",
+	       ret ? ret->uid : 0,
+	       ret ? ret->hash : 0);
+    }
+
+  return ret;
+}
+
+/* Invalidate any entries in reg_values that overlap REGNO.  This is called
+   if REGNO is changing.  MODE is the mode of the assignment to REGNO, which
+   is used to determine how many hard registers are being changed.  If MODE
+   is VOIDmode, then only REGNO is being changed; this is used when
+   invalidating call clobbered registers across a call.  */
+
+static void
+cselib_invalidate_regno (unsigned int regno, enum machine_mode mode)
+{
+  unsigned int endregno;
+  unsigned int i;
+
+  /* If we see pseudos after reload, something is _wrong_.  */
+  gcc_assert (!reload_completed || regno < FIRST_PSEUDO_REGISTER
+	      || reg_renumber[regno] < 0);
+
+  /* Determine the range of registers that must be invalidated.  For
+     pseudos, only REGNO is affected.  For hard regs, we must take MODE
+     into account, and we must also invalidate lower register numbers
+     if they contain values that overlap REGNO.  */
+  if (regno < FIRST_PSEUDO_REGISTER)
+    {
+      gcc_assert (mode != VOIDmode);
+
+      if (regno < max_value_regs)
+	i = 0;
+      else
+	i = regno - max_value_regs;
+
+      endregno = end_hard_regno (mode, regno);
+    }
+  else
+    {
+      i = regno;
+      endregno = regno + 1;
+    }
+
+  for (; i < endregno; i++)
+    {
+      struct elt_list **l = &REG_VALUES (i);
+
+      /* Go through all known values for this reg; if it overlaps the range
+	 we're invalidating, remove the value.  */
+      while (*l)
+	{
+	  cselib_val *v = (*l)->elt;
+	  bool had_locs;
+	  rtx setting_insn;
+	  struct elt_loc_list **p;
+	  unsigned int this_last = i;
+
+	  if (i < FIRST_PSEUDO_REGISTER && v != NULL)
+	    this_last = end_hard_regno (GET_MODE (v->val_rtx), i) - 1;
+
+	  if (this_last < regno || v == NULL
+	      || (v == cfa_base_preserved_val
+		  && i == cfa_base_preserved_regno))
+	    {
+	      l = &(*l)->next;
+	      continue;
+	    }
+
+	  /* We have an overlap.  */
+	  if (*l == REG_VALUES (i))
+	    {
+	      /* Maintain the invariant that the first entry of
+		 REG_VALUES, if present, must be the value used to set
+		 the register, or NULL.  This is also nice because
+		 then we won't push the same regno onto user_regs
+		 multiple times.  */
+	      (*l)->elt = NULL;
+	      l = &(*l)->next;
+	    }
+	  else
+	    unchain_one_elt_list (l);
+
+	  v = canonical_cselib_val (v);
+
+	  had_locs = v->locs != NULL;
+	  setting_insn = v->locs ? v->locs->setting_insn : NULL;
+
+	  /* Now, we clear the mapping from value to reg.  It must exist, so
+	     this code will crash intentionally if it doesn't.  */
+	  for (p = &v->locs; ; p = &(*p)->next)
+	    {
+	      rtx x = (*p)->loc;
+
+	      if (REG_P (x) && REGNO (x) == i)
+		{
+		  unchain_one_elt_loc_list (p);
+		  break;
+		}
+	    }
+
+	  if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
+	    {
+	      if (setting_insn && DEBUG_INSN_P (setting_insn))
+		n_useless_debug_values++;
+	      else
+		n_useless_values++;
+	    }
+	}
+    }
+}
+
+/* Invalidate any locations in the table which are changed because of a
+   store to MEM_RTX.  If this is called because of a non-const call
+   instruction, MEM_RTX is (mem:BLK const0_rtx).  */
+
+static void
+cselib_invalidate_mem (rtx mem_rtx)
+{
+  cselib_val **vp, *v, *next;
+  int num_mems = 0;
+  rtx mem_addr;
+
+  mem_addr = canon_rtx (get_addr (XEXP (mem_rtx, 0)));
+  mem_rtx = canon_rtx (mem_rtx);
+
+  vp = &first_containing_mem;
+  for (v = *vp; v != &dummy_val; v = next)
+    {
+      bool has_mem = false;
+      struct elt_loc_list **p = &v->locs;
+      bool had_locs = v->locs != NULL;
+      rtx setting_insn = v->locs ? v->locs->setting_insn : NULL;
+
+      while (*p)
+	{
+	  rtx x = (*p)->loc;
+	  cselib_val *addr;
+	  struct elt_list **mem_chain;
+
+	  /* MEMs may occur in locations only at the top level; below
+	     that every MEM or REG is substituted by its VALUE.  */
+	  if (!MEM_P (x))
+	    {
+	      p = &(*p)->next;
+	      continue;
+	    }
+	  if (num_mems < PARAM_VALUE (PARAM_MAX_CSELIB_MEMORY_LOCATIONS)
+	      && ! canon_anti_dependence (x, false, mem_rtx,
+					  GET_MODE (mem_rtx), mem_addr))
+	    {
+	      has_mem = true;
+	      num_mems++;
+	      p = &(*p)->next;
+	      continue;
+	    }
+
+	  /* This one overlaps.  */
+	  /* We must have a mapping from this MEM's address to the
+	     value (E).  Remove that, too.  */
+	  addr = cselib_lookup (XEXP (x, 0), VOIDmode, 0, GET_MODE (x));
+	  addr = canonical_cselib_val (addr);
+	  gcc_checking_assert (v == canonical_cselib_val (v));
+	  mem_chain = &addr->addr_list;
+	  for (;;)
+	    {
+	      cselib_val *canon = canonical_cselib_val ((*mem_chain)->elt);
+
+	      if (canon == v)
+		{
+		  unchain_one_elt_list (mem_chain);
+		  break;
+		}
+
+	      /* Record canonicalized elt.  */
+	      (*mem_chain)->elt = canon;
+
+	      mem_chain = &(*mem_chain)->next;
+	    }
+
+	  unchain_one_elt_loc_list (p);
+	}
+
+      if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
+	{
+	  if (setting_insn && DEBUG_INSN_P (setting_insn))
+	    n_useless_debug_values++;
+	  else
+	    n_useless_values++;
+	}
+
+      next = v->next_containing_mem;
+      if (has_mem)
+	{
+	  *vp = v;
+	  vp = &(*vp)->next_containing_mem;
+	}
+      else
+	v->next_containing_mem = NULL;
+    }
+  *vp = &dummy_val;
+}
+
+/* Invalidate DEST, which is being assigned to or clobbered.  */
+
+void
+cselib_invalidate_rtx (rtx dest)
+{
+  while (GET_CODE (dest) == SUBREG
+	 || GET_CODE (dest) == ZERO_EXTRACT
+	 || GET_CODE (dest) == STRICT_LOW_PART)
+    dest = XEXP (dest, 0);
+
+  if (REG_P (dest))
+    cselib_invalidate_regno (REGNO (dest), GET_MODE (dest));
+  else if (MEM_P (dest))
+    cselib_invalidate_mem (dest);
+}
+
+/* A wrapper for cselib_invalidate_rtx to be called via note_stores.  */
+
+static void
+cselib_invalidate_rtx_note_stores (rtx dest, const_rtx ignore ATTRIBUTE_UNUSED,
+				   void *data ATTRIBUTE_UNUSED)
+{
+  cselib_invalidate_rtx (dest);
+}
+
+/* Record the result of a SET instruction.  DEST is being set; the source
+   contains the value described by SRC_ELT.  If DEST is a MEM, DEST_ADDR_ELT
+   describes its address.  */
+
+static void
+cselib_record_set (rtx dest, cselib_val *src_elt, cselib_val *dest_addr_elt)
+{
+  int dreg = REG_P (dest) ? (int) REGNO (dest) : -1;
+
+  if (src_elt == 0 || side_effects_p (dest))
+    return;
+
+  if (dreg >= 0)
+    {
+      if (dreg < FIRST_PSEUDO_REGISTER)
+	{
+	  unsigned int n = hard_regno_nregs[dreg][GET_MODE (dest)];
+
+	  if (n > max_value_regs)
+	    max_value_regs = n;
+	}
+
+      if (REG_VALUES (dreg) == 0)
+	{
+	  used_regs[n_used_regs++] = dreg;
+	  REG_VALUES (dreg) = new_elt_list (REG_VALUES (dreg), src_elt);
+	}
+      else
+	{
+	  /* The register should have been invalidated.  */
+	  gcc_assert (REG_VALUES (dreg)->elt == 0);
+	  REG_VALUES (dreg)->elt = src_elt;
+	}
+
+      if (src_elt->locs == 0 && !PRESERVED_VALUE_P (src_elt->val_rtx))
+	n_useless_values--;
+      new_elt_loc_list (src_elt, dest);
+    }
+  else if (MEM_P (dest) && dest_addr_elt != 0
+	   && cselib_record_memory)
+    {
+      if (src_elt->locs == 0 && !PRESERVED_VALUE_P (src_elt->val_rtx))
+	n_useless_values--;
+      add_mem_for_addr (dest_addr_elt, src_elt, dest);
+    }
+}
+
+/* Make ELT and X's VALUE equivalent to each other at INSN.  */
+
+void
+cselib_add_permanent_equiv (cselib_val *elt, rtx x, rtx insn)
+{
+  cselib_val *nelt;
+  rtx save_cselib_current_insn = cselib_current_insn;
+
+  gcc_checking_assert (elt);
+  gcc_checking_assert (PRESERVED_VALUE_P (elt->val_rtx));
+  gcc_checking_assert (!side_effects_p (x));
+
+  cselib_current_insn = insn;
+
+  nelt = cselib_lookup (x, GET_MODE (elt->val_rtx), 1, VOIDmode);
+
+  if (nelt != elt)
+    {
+      cselib_any_perm_equivs = true;
+
+      if (!PRESERVED_VALUE_P (nelt->val_rtx))
+	cselib_preserve_value (nelt);
+
+      new_elt_loc_list (nelt, elt->val_rtx);
+    }
+
+  cselib_current_insn = save_cselib_current_insn;
+}
+
+/* Return TRUE if any permanent equivalences have been recorded since
+   the table was last initialized.  */
+bool
+cselib_have_permanent_equivalences (void)
+{
+  return cselib_any_perm_equivs;
+}
+
+/* There is no good way to determine how many elements there can be
+   in a PARALLEL.  Since it's fairly cheap, use a really large number.  */
+#define MAX_SETS (FIRST_PSEUDO_REGISTER * 2)
+
+struct cselib_record_autoinc_data
+{
+  struct cselib_set *sets;
+  int n_sets;
+};
+
+/* Callback for for_each_inc_dec.  Records in ARG the SETs implied by
+   autoinc RTXs: SRC plus SRCOFF if non-NULL is stored in DEST.  */
+
+static int
+cselib_record_autoinc_cb (rtx mem ATTRIBUTE_UNUSED, rtx op ATTRIBUTE_UNUSED,
+			  rtx dest, rtx src, rtx srcoff, void *arg)
+{
+  struct cselib_record_autoinc_data *data;
+  data = (struct cselib_record_autoinc_data *)arg;
+
+  data->sets[data->n_sets].dest = dest;
+
+  if (srcoff)
+    data->sets[data->n_sets].src = gen_rtx_PLUS (GET_MODE (src), src, srcoff);
+  else
+    data->sets[data->n_sets].src = src;
+
+  data->n_sets++;
+
+  return -1;
+}
+
+/* Record the effects of any sets and autoincs in INSN.  */
+static void
+cselib_record_sets (rtx insn)
+{
+  int n_sets = 0;
+  int i;
+  struct cselib_set sets[MAX_SETS];
+  rtx body = PATTERN (insn);
+  rtx cond = 0;
+  int n_sets_before_autoinc;
+  struct cselib_record_autoinc_data data;
+
+  body = PATTERN (insn);
+  if (GET_CODE (body) == COND_EXEC)
+    {
+      cond = COND_EXEC_TEST (body);
+      body = COND_EXEC_CODE (body);
+    }
+
+  /* Find all sets.  */
+  if (GET_CODE (body) == SET)
+    {
+      sets[0].src = SET_SRC (body);
+      sets[0].dest = SET_DEST (body);
+      n_sets = 1;
+    }
+  else if (GET_CODE (body) == PARALLEL)
+    {
+      /* Look through the PARALLEL and record the values being
+	 set, if possible.  Also handle any CLOBBERs.  */
+      for (i = XVECLEN (body, 0) - 1; i >= 0; --i)
+	{
+	  rtx x = XVECEXP (body, 0, i);
+
+	  if (GET_CODE (x) == SET)
+	    {
+	      sets[n_sets].src = SET_SRC (x);
+	      sets[n_sets].dest = SET_DEST (x);
+	      n_sets++;
+	    }
+	}
+    }
+
+  if (n_sets == 1
+      && MEM_P (sets[0].src)
+      && !cselib_record_memory
+      && MEM_READONLY_P (sets[0].src))
+    {
+      rtx note = find_reg_equal_equiv_note (insn);
+
+      if (note && CONSTANT_P (XEXP (note, 0)))
+	sets[0].src = XEXP (note, 0);
+    }
+
+  data.sets = sets;
+  data.n_sets = n_sets_before_autoinc = n_sets;
+  for_each_inc_dec (&insn, cselib_record_autoinc_cb, &data);
+  n_sets = data.n_sets;
+
+  /* Look up the values that are read.  Do this before invalidating the
+     locations that are written.  */
+  for (i = 0; i < n_sets; i++)
+    {
+      rtx dest = sets[i].dest;
+
+      /* A STRICT_LOW_PART can be ignored; we'll record the equivalence for
+         the low part after invalidating any knowledge about larger modes.  */
+      if (GET_CODE (sets[i].dest) == STRICT_LOW_PART)
+	sets[i].dest = dest = XEXP (dest, 0);
+
+      /* We don't know how to record anything but REG or MEM.  */
+      if (REG_P (dest)
+	  || (MEM_P (dest) && cselib_record_memory))
+        {
+	  rtx src = sets[i].src;
+	  if (cond)
+	    src = gen_rtx_IF_THEN_ELSE (GET_MODE (dest), cond, src, dest);
+	  sets[i].src_elt = cselib_lookup (src, GET_MODE (dest), 1, VOIDmode);
+	  if (MEM_P (dest))
+	    {
+	      enum machine_mode address_mode = get_address_mode (dest);
+
+	      sets[i].dest_addr_elt = cselib_lookup (XEXP (dest, 0),
+						     address_mode, 1,
+						     GET_MODE (dest));
+	    }
+	  else
+	    sets[i].dest_addr_elt = 0;
+	}
+    }
+
+  if (cselib_record_sets_hook)
+    cselib_record_sets_hook (insn, sets, n_sets);
+
+  /* Invalidate all locations written by this insn.  Note that the elts we
+     looked up in the previous loop aren't affected, just some of their
+     locations may go away.  */
+  note_stores (body, cselib_invalidate_rtx_note_stores, NULL);
+
+  for (i = n_sets_before_autoinc; i < n_sets; i++)
+    cselib_invalidate_rtx (sets[i].dest);
+
+  /* If this is an asm, look for duplicate sets.  This can happen when the
+     user uses the same value as an output multiple times.  This is valid
+     if the outputs are not actually used thereafter.  Treat this case as
+     if the value isn't actually set.  We do this by smashing the destination
+     to pc_rtx, so that we won't record the value later.  */
+  if (n_sets >= 2 && asm_noperands (body) >= 0)
+    {
+      for (i = 0; i < n_sets; i++)
+	{
+	  rtx dest = sets[i].dest;
+	  if (REG_P (dest) || MEM_P (dest))
+	    {
+	      int j;
+	      for (j = i + 1; j < n_sets; j++)
+		if (rtx_equal_p (dest, sets[j].dest))
+		  {
+		    sets[i].dest = pc_rtx;
+		    sets[j].dest = pc_rtx;
+		  }
+	    }
+	}
+    }
+
+  /* Now enter the equivalences in our tables.  */
+  for (i = 0; i < n_sets; i++)
+    {
+      rtx dest = sets[i].dest;
+      if (REG_P (dest)
+	  || (MEM_P (dest) && cselib_record_memory))
+	cselib_record_set (dest, sets[i].src_elt, sets[i].dest_addr_elt);
+    }
+}
+
+/* Return true if INSN in the prologue initializes hard_frame_pointer_rtx.  */
+
+bool
+fp_setter_insn (rtx insn)
+{
+  rtx expr, pat = NULL_RTX;
+
+  if (!RTX_FRAME_RELATED_P (insn))
+    return false;
+
+  expr = find_reg_note (insn, REG_FRAME_RELATED_EXPR, NULL_RTX);
+  if (expr)
+    pat = XEXP (expr, 0);
+  if (!modified_in_p (hard_frame_pointer_rtx, pat ? pat : insn))
+    return false;
+
+  /* Don't return true for frame pointer restores in the epilogue.  */
+  if (find_reg_note (insn, REG_CFA_RESTORE, hard_frame_pointer_rtx))
+    return false;
+  return true;
+}
+
+/* Record the effects of INSN.  */
+
+void
+cselib_process_insn (rtx insn)
+{
+  int i;
+  rtx x;
+
+  cselib_current_insn = insn;
+
+  /* Forget everything at a CODE_LABEL or a setjmp.  */
+  if ((LABEL_P (insn)
+       || (CALL_P (insn)
+	   && find_reg_note (insn, REG_SETJMP, NULL)))
+      && !cselib_preserve_constants)
+    {
+      cselib_reset_table (next_uid);
+      cselib_current_insn = NULL_RTX;
+      return;
+    }
+
+  if (! INSN_P (insn))
+    {
+      cselib_current_insn = NULL_RTX;
+      return;
+    }
+
+  /* If this is a call instruction, forget anything stored in a
+     call clobbered register, or, if this is not a const call, in
+     memory.  */
+  if (CALL_P (insn))
+    {
+      for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+	if (call_used_regs[i]
+	    || (REG_VALUES (i) && REG_VALUES (i)->elt
+		&& HARD_REGNO_CALL_PART_CLOBBERED (i,
+		      GET_MODE (REG_VALUES (i)->elt->val_rtx))))
+	  cselib_invalidate_regno (i, reg_raw_mode[i]);
+
+      /* Since it is not clear how cselib is going to be used, be
+	 conservative here and treat looping pure or const functions
+	 as if they were regular functions.  */
+      if (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn)
+	  || !(RTL_CONST_OR_PURE_CALL_P (insn)))
+	cselib_invalidate_mem (callmem);
+    }
+
+  cselib_record_sets (insn);
+
+  /* Look for any CLOBBERs in CALL_INSN_FUNCTION_USAGE, but only
+     after we have processed the insn.  */
+  if (CALL_P (insn))
+    {
+      for (x = CALL_INSN_FUNCTION_USAGE (insn); x; x = XEXP (x, 1))
+	if (GET_CODE (XEXP (x, 0)) == CLOBBER)
+	  cselib_invalidate_rtx (XEXP (XEXP (x, 0), 0));
+      /* Flush evertything on setjmp.  */
+      if (cselib_preserve_constants
+	  && find_reg_note (insn, REG_SETJMP, NULL))
+	{
+	  cselib_preserve_only_values ();
+	  cselib_reset_table (next_uid);
+	}
+    }
+
+  /* On setter of the hard frame pointer if frame_pointer_needed,
+     invalidate stack_pointer_rtx, so that sp and {,h}fp based
+     VALUEs are distinct.  */
+  if (reload_completed
+      && frame_pointer_needed
+      && fp_setter_insn (insn))
+    cselib_invalidate_rtx (stack_pointer_rtx);
+
+  cselib_current_insn = NULL_RTX;
+
+  if (n_useless_values > MAX_USELESS_VALUES
+      /* remove_useless_values is linear in the hash table size.  Avoid
+         quadratic behavior for very large hashtables with very few
+	 useless elements.  */
+      && ((unsigned int)n_useless_values
+	  > (cselib_hash_table.elements () - n_debug_values) / 4))
+    remove_useless_values ();
+}
+
+/* Initialize cselib for one pass.  The caller must also call
+   init_alias_analysis.  */
+
+void
+cselib_init (int record_what)
+{
+  elt_list_pool = create_alloc_pool ("elt_list",
+				     sizeof (struct elt_list), 10);
+  elt_loc_list_pool = create_alloc_pool ("elt_loc_list",
+				         sizeof (struct elt_loc_list), 10);
+  cselib_val_pool = create_alloc_pool ("cselib_val_list",
+				       sizeof (cselib_val), 10);
+  value_pool = create_alloc_pool ("value", RTX_CODE_SIZE (VALUE), 100);
+  cselib_record_memory = record_what & CSELIB_RECORD_MEMORY;
+  cselib_preserve_constants = record_what & CSELIB_PRESERVE_CONSTANTS;
+  cselib_any_perm_equivs = false;
+
+  /* (mem:BLK (scratch)) is a special mechanism to conflict with everything,
+     see canon_true_dependence.  This is only created once.  */
+  if (! callmem)
+    callmem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode));
+
+  cselib_nregs = max_reg_num ();
+
+  /* We preserve reg_values to allow expensive clearing of the whole thing.
+     Reallocate it however if it happens to be too large.  */
+  if (!reg_values || reg_values_size < cselib_nregs
+      || (reg_values_size > 10 && reg_values_size > cselib_nregs * 4))
+    {
+      free (reg_values);
+      /* Some space for newly emit instructions so we don't end up
+	 reallocating in between passes.  */
+      reg_values_size = cselib_nregs + (63 + cselib_nregs) / 16;
+      reg_values = XCNEWVEC (struct elt_list *, reg_values_size);
+    }
+  used_regs = XNEWVEC (unsigned int, cselib_nregs);
+  n_used_regs = 0;
+  cselib_hash_table.create (31);
+  if (cselib_preserve_constants)
+    cselib_preserved_hash_table.create (31);
+  next_uid = 1;
+}
+
+/* Called when the current user is done with cselib.  */
+
+void
+cselib_finish (void)
+{
+  bool preserved = cselib_preserve_constants;
+  cselib_discard_hook = NULL;
+  cselib_preserve_constants = false;
+  cselib_any_perm_equivs = false;
+  cfa_base_preserved_val = NULL;
+  cfa_base_preserved_regno = INVALID_REGNUM;
+  free_alloc_pool (elt_list_pool);
+  free_alloc_pool (elt_loc_list_pool);
+  free_alloc_pool (cselib_val_pool);
+  free_alloc_pool (value_pool);
+  cselib_clear_table ();
+  cselib_hash_table.dispose ();
+  if (preserved)
+    cselib_preserved_hash_table.dispose ();
+  free (used_regs);
+  used_regs = 0;
+  n_useless_values = 0;
+  n_useless_debug_values = 0;
+  n_debug_values = 0;
+  next_uid = 0;
+}
+
+/* Dump the cselib_val *X to FILE *OUT.  */
+
+int
+dump_cselib_val (cselib_val **x, FILE *out)
+{
+  cselib_val *v = *x;
+  bool need_lf = true;
+
+  print_inline_rtx (out, v->val_rtx, 0);
+
+  if (v->locs)
+    {
+      struct elt_loc_list *l = v->locs;
+      if (need_lf)
+	{
+	  fputc ('\n', out);
+	  need_lf = false;
+	}
+      fputs (" locs:", out);
+      do
+	{
+	  if (l->setting_insn)
+	    fprintf (out, "\n  from insn %i ",
+		     INSN_UID (l->setting_insn));
+	  else
+	    fprintf (out, "\n   ");
+	  print_inline_rtx (out, l->loc, 4);
+	}
+      while ((l = l->next));
+      fputc ('\n', out);
+    }
+  else
+    {
+      fputs (" no locs", out);
+      need_lf = true;
+    }
+
+  if (v->addr_list)
+    {
+      struct elt_list *e = v->addr_list;
+      if (need_lf)
+	{
+	  fputc ('\n', out);
+	  need_lf = false;
+	}
+      fputs (" addr list:", out);
+      do
+	{
+	  fputs ("\n  ", out);
+	  print_inline_rtx (out, e->elt->val_rtx, 2);
+	}
+      while ((e = e->next));
+      fputc ('\n', out);
+    }
+  else
+    {
+      fputs (" no addrs", out);
+      need_lf = true;
+    }
+
+  if (v->next_containing_mem == &dummy_val)
+    fputs (" last mem\n", out);
+  else if (v->next_containing_mem)
+    {
+      fputs (" next mem ", out);
+      print_inline_rtx (out, v->next_containing_mem->val_rtx, 2);
+      fputc ('\n', out);
+    }
+  else if (need_lf)
+    fputc ('\n', out);
+
+  return 1;
+}
+
+/* Dump to OUT everything in the CSELIB table.  */
+
+void
+dump_cselib_table (FILE *out)
+{
+  fprintf (out, "cselib hash table:\n");
+  cselib_hash_table.traverse <FILE *, dump_cselib_val> (out);
+  fprintf (out, "cselib preserved hash table:\n");
+  cselib_preserved_hash_table.traverse <FILE *, dump_cselib_val> (out);
+  if (first_containing_mem != &dummy_val)
+    {
+      fputs ("first mem ", out);
+      print_inline_rtx (out, first_containing_mem->val_rtx, 2);
+      fputc ('\n', out);
+    }
+  fprintf (out, "next uid %i\n", next_uid);
+}
+
+#include "gt-cselib.h"