--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/sched-deps.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,3518 @@
+/* Instruction scheduling pass.  This file computes dependencies between
+   instructions.
+   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998,
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+   Free Software Foundation, Inc.
+   Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by,
+   and currently maintained by, Jim Wilson (wilson@cygnus.com)
+
+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 "toplev.h"
+#include "rtl.h"
+#include "tm_p.h"
+#include "hard-reg-set.h"
+#include "regs.h"
+#include "function.h"
+#include "flags.h"
+#include "insn-config.h"
+#include "insn-attr.h"
+#include "except.h"
+#include "toplev.h"
+#include "recog.h"
+#include "sched-int.h"
+#include "params.h"
+#include "cselib.h"
+
+#ifdef INSN_SCHEDULING
+
+#ifdef ENABLE_CHECKING
+#define CHECK (true)
+#else
+#define CHECK (false)
+#endif
+
+/* Holds current parameters for the dependency analyzer.  */
+struct sched_deps_info_def *sched_deps_info;
+
+/* The data is specific to the Haifa scheduler.  */
+VEC(haifa_deps_insn_data_def, heap) *h_d_i_d = NULL;
+
+/* Return the major type present in the DS.  */
+enum reg_note
+ds_to_dk (ds_t ds)
+{
+  if (ds & DEP_TRUE)
+    return REG_DEP_TRUE;
+
+  if (ds & DEP_OUTPUT)
+    return REG_DEP_OUTPUT;
+
+  gcc_assert (ds & DEP_ANTI);
+
+  return REG_DEP_ANTI;
+}
+
+/* Return equivalent dep_status.  */
+ds_t
+dk_to_ds (enum reg_note dk)
+{
+  switch (dk)
+    {
+    case REG_DEP_TRUE:
+      return DEP_TRUE;
+
+    case REG_DEP_OUTPUT:
+      return DEP_OUTPUT;
+
+    default:
+      gcc_assert (dk == REG_DEP_ANTI);
+      return DEP_ANTI;
+    }
+}
+
+/* Functions to operate with dependence information container - dep_t.  */
+
+/* Init DEP with the arguments.  */
+void
+init_dep_1 (dep_t dep, rtx pro, rtx con, enum reg_note type, ds_t ds)
+{
+  DEP_PRO (dep) = pro;
+  DEP_CON (dep) = con;
+  DEP_TYPE (dep) = type;
+  DEP_STATUS (dep) = ds;
+}
+
+/* Init DEP with the arguments.
+   While most of the scheduler (including targets) only need the major type
+   of the dependency, it is convenient to hide full dep_status from them.  */
+void
+init_dep (dep_t dep, rtx pro, rtx con, enum reg_note kind)
+{
+  ds_t ds;
+
+  if ((current_sched_info->flags & USE_DEPS_LIST))
+    ds = dk_to_ds (kind);
+  else
+    ds = -1;
+
+  init_dep_1 (dep, pro, con, kind, ds);
+}
+
+/* Make a copy of FROM in TO.  */
+static void
+copy_dep (dep_t to, dep_t from)
+{
+  memcpy (to, from, sizeof (*to));
+}
+
+static void dump_ds (FILE *, ds_t);
+
+/* Define flags for dump_dep ().  */
+
+/* Dump producer of the dependence.  */
+#define DUMP_DEP_PRO (2)
+
+/* Dump consumer of the dependence.  */
+#define DUMP_DEP_CON (4)
+
+/* Dump type of the dependence.  */
+#define DUMP_DEP_TYPE (8)
+
+/* Dump status of the dependence.  */
+#define DUMP_DEP_STATUS (16)
+
+/* Dump all information about the dependence.  */
+#define DUMP_DEP_ALL (DUMP_DEP_PRO | DUMP_DEP_CON | DUMP_DEP_TYPE	\
+		      |DUMP_DEP_STATUS)
+
+/* Dump DEP to DUMP.
+   FLAGS is a bit mask specifying what information about DEP needs
+   to be printed.
+   If FLAGS has the very first bit set, then dump all information about DEP
+   and propagate this bit into the callee dump functions.  */
+static void
+dump_dep (FILE *dump, dep_t dep, int flags)
+{
+  if (flags & 1)
+    flags |= DUMP_DEP_ALL;
+
+  fprintf (dump, "<");
+
+  if (flags & DUMP_DEP_PRO)
+    fprintf (dump, "%d; ", INSN_UID (DEP_PRO (dep)));
+
+  if (flags & DUMP_DEP_CON)
+    fprintf (dump, "%d; ", INSN_UID (DEP_CON (dep)));
+
+  if (flags & DUMP_DEP_TYPE)
+    {
+      char t;
+      enum reg_note type = DEP_TYPE (dep);
+
+      switch (type)
+	{
+	case REG_DEP_TRUE:
+	  t = 't';
+	  break;
+
+	case REG_DEP_OUTPUT:
+	  t = 'o';
+	  break;
+
+	case REG_DEP_ANTI:
+	  t = 'a';
+	  break;
+
+	default:
+	  gcc_unreachable ();
+	  break;
+	}
+
+      fprintf (dump, "%c; ", t);
+    }
+
+  if (flags & DUMP_DEP_STATUS)
+    {
+      if (current_sched_info->flags & USE_DEPS_LIST)
+	dump_ds (dump, DEP_STATUS (dep));
+    }
+
+  fprintf (dump, ">");
+}
+
+/* Default flags for dump_dep ().  */
+static int dump_dep_flags = (DUMP_DEP_PRO | DUMP_DEP_CON);
+
+/* Dump all fields of DEP to STDERR.  */
+void
+sd_debug_dep (dep_t dep)
+{
+  dump_dep (stderr, dep, 1);
+  fprintf (stderr, "\n");
+}
+
+/* Functions to operate with a single link from the dependencies lists -
+   dep_link_t.  */
+
+/* Attach L to appear after link X whose &DEP_LINK_NEXT (X) is given by
+   PREV_NEXT_P.  */
+static void
+attach_dep_link (dep_link_t l, dep_link_t *prev_nextp)
+{
+  dep_link_t next = *prev_nextp;
+
+  gcc_assert (DEP_LINK_PREV_NEXTP (l) == NULL
+	      && DEP_LINK_NEXT (l) == NULL);
+
+  /* Init node being inserted.  */
+  DEP_LINK_PREV_NEXTP (l) = prev_nextp;
+  DEP_LINK_NEXT (l) = next;
+
+  /* Fix next node.  */
+  if (next != NULL)
+    {
+      gcc_assert (DEP_LINK_PREV_NEXTP (next) == prev_nextp);
+
+      DEP_LINK_PREV_NEXTP (next) = &DEP_LINK_NEXT (l);
+    }
+
+  /* Fix prev node.  */
+  *prev_nextp = l;
+}
+
+/* Add dep_link LINK to deps_list L.  */
+static void
+add_to_deps_list (dep_link_t link, deps_list_t l)
+{
+  attach_dep_link (link, &DEPS_LIST_FIRST (l));
+
+  ++DEPS_LIST_N_LINKS (l);
+}
+
+/* Detach dep_link L from the list.  */
+static void
+detach_dep_link (dep_link_t l)
+{
+  dep_link_t *prev_nextp = DEP_LINK_PREV_NEXTP (l);
+  dep_link_t next = DEP_LINK_NEXT (l);
+
+  *prev_nextp = next;
+
+  if (next != NULL)
+    DEP_LINK_PREV_NEXTP (next) = prev_nextp;
+
+  DEP_LINK_PREV_NEXTP (l) = NULL;
+  DEP_LINK_NEXT (l) = NULL;
+}
+
+/* Remove link LINK from list LIST.  */
+static void
+remove_from_deps_list (dep_link_t link, deps_list_t list)
+{
+  detach_dep_link (link);
+
+  --DEPS_LIST_N_LINKS (list);
+}
+
+/* Move link LINK from list FROM to list TO.  */
+static void
+move_dep_link (dep_link_t link, deps_list_t from, deps_list_t to)
+{
+  remove_from_deps_list (link, from);
+  add_to_deps_list (link, to);
+}
+
+/* Return true of LINK is not attached to any list.  */
+static bool
+dep_link_is_detached_p (dep_link_t link)
+{
+  return DEP_LINK_PREV_NEXTP (link) == NULL;
+}
+
+/* Pool to hold all dependency nodes (dep_node_t).  */
+static alloc_pool dn_pool;
+
+/* Number of dep_nodes out there.  */
+static int dn_pool_diff = 0;
+
+/* Create a dep_node.  */
+static dep_node_t
+create_dep_node (void)
+{
+  dep_node_t n = (dep_node_t) pool_alloc (dn_pool);
+  dep_link_t back = DEP_NODE_BACK (n);
+  dep_link_t forw = DEP_NODE_FORW (n);
+
+  DEP_LINK_NODE (back) = n;
+  DEP_LINK_NEXT (back) = NULL;
+  DEP_LINK_PREV_NEXTP (back) = NULL;
+
+  DEP_LINK_NODE (forw) = n;
+  DEP_LINK_NEXT (forw) = NULL;
+  DEP_LINK_PREV_NEXTP (forw) = NULL;
+
+  ++dn_pool_diff;
+
+  return n;
+}
+
+/* Delete dep_node N.  N must not be connected to any deps_list.  */
+static void
+delete_dep_node (dep_node_t n)
+{
+  gcc_assert (dep_link_is_detached_p (DEP_NODE_BACK (n))
+	      && dep_link_is_detached_p (DEP_NODE_FORW (n)));
+
+  --dn_pool_diff;
+
+  pool_free (dn_pool, n);
+}
+
+/* Pool to hold dependencies lists (deps_list_t).  */
+static alloc_pool dl_pool;
+
+/* Number of deps_lists out there.  */
+static int dl_pool_diff = 0;
+
+/* Functions to operate with dependences lists - deps_list_t.  */
+
+/* Return true if list L is empty.  */
+static bool
+deps_list_empty_p (deps_list_t l)
+{
+  return DEPS_LIST_N_LINKS (l) == 0;
+}
+
+/* Create a new deps_list.  */
+static deps_list_t
+create_deps_list (void)
+{
+  deps_list_t l = (deps_list_t) pool_alloc (dl_pool);
+
+  DEPS_LIST_FIRST (l) = NULL;
+  DEPS_LIST_N_LINKS (l) = 0;
+
+  ++dl_pool_diff;
+  return l;
+}
+
+/* Free deps_list L.  */
+static void
+free_deps_list (deps_list_t l)
+{
+  gcc_assert (deps_list_empty_p (l));
+
+  --dl_pool_diff;
+
+  pool_free (dl_pool, l);
+}
+
+/* Return true if there is no dep_nodes and deps_lists out there.
+   After the region is scheduled all the dependency nodes and lists
+   should [generally] be returned to pool.  */
+bool
+deps_pools_are_empty_p (void)
+{
+  return dn_pool_diff == 0 && dl_pool_diff == 0;
+}
+
+/* Remove all elements from L.  */
+static void
+clear_deps_list (deps_list_t l)
+{
+  do
+    {
+      dep_link_t link = DEPS_LIST_FIRST (l);
+
+      if (link == NULL)
+	break;
+
+      remove_from_deps_list (link, l);
+    }
+  while (1);
+}
+
+static regset reg_pending_sets;
+static regset reg_pending_clobbers;
+static regset reg_pending_uses;
+static enum reg_pending_barrier_mode reg_pending_barrier;
+
+/* To speed up the test for duplicate dependency links we keep a
+   record of dependencies created by add_dependence when the average
+   number of instructions in a basic block is very large.
+
+   Studies have shown that there is typically around 5 instructions between
+   branches for typical C code.  So we can make a guess that the average
+   basic block is approximately 5 instructions long; we will choose 100X
+   the average size as a very large basic block.
+
+   Each insn has associated bitmaps for its dependencies.  Each bitmap
+   has enough entries to represent a dependency on any other insn in
+   the insn chain.  All bitmap for true dependencies cache is
+   allocated then the rest two ones are also allocated.  */
+static bitmap_head *true_dependency_cache = NULL;
+static bitmap_head *output_dependency_cache = NULL;
+static bitmap_head *anti_dependency_cache = NULL;
+static bitmap_head *spec_dependency_cache = NULL;
+static int cache_size;
+
+static int deps_may_trap_p (const_rtx);
+static void add_dependence_list (rtx, rtx, int, enum reg_note);
+static void add_dependence_list_and_free (struct deps *, rtx, 
+                                          rtx *, int, enum reg_note);
+static void delete_all_dependences (rtx);
+static void fixup_sched_groups (rtx);
+
+static void flush_pending_lists (struct deps *, rtx, int, int);
+static void sched_analyze_1 (struct deps *, rtx, rtx);
+static void sched_analyze_2 (struct deps *, rtx, rtx);
+static void sched_analyze_insn (struct deps *, rtx, rtx);
+
+static bool sched_has_condition_p (const_rtx);
+static int conditions_mutex_p (const_rtx, const_rtx, bool, bool);
+
+static enum DEPS_ADJUST_RESULT maybe_add_or_update_dep_1 (dep_t, bool,
+							  rtx, rtx);
+static enum DEPS_ADJUST_RESULT add_or_update_dep_1 (dep_t, bool, rtx, rtx);
+
+#ifdef ENABLE_CHECKING
+static void check_dep (dep_t, bool);
+#endif
+
+/* Return nonzero if a load of the memory reference MEM can cause a trap.  */
+
+static int
+deps_may_trap_p (const_rtx mem)
+{
+  const_rtx addr = XEXP (mem, 0);
+
+  if (REG_P (addr) && REGNO (addr) >= FIRST_PSEUDO_REGISTER)
+    {
+      const_rtx t = get_reg_known_value (REGNO (addr));
+      if (t)
+	addr = t;
+    }
+  return rtx_addr_can_trap_p (addr);
+}
+
+
+/* Find the condition under which INSN is executed.  If REV is not NULL,
+   it is set to TRUE when the returned comparison should be reversed
+   to get the actual condition.  */
+static rtx
+sched_get_condition_with_rev (const_rtx insn, bool *rev)
+{
+  rtx pat = PATTERN (insn);
+  rtx src;
+
+  if (pat == 0)
+    return 0;
+
+  if (rev)
+    *rev = false;
+
+  if (GET_CODE (pat) == COND_EXEC)
+    return COND_EXEC_TEST (pat);
+
+  if (!any_condjump_p (insn) || !onlyjump_p (insn))
+    return 0;
+
+  src = SET_SRC (pc_set (insn));
+
+  if (XEXP (src, 2) == pc_rtx)
+    return XEXP (src, 0);
+  else if (XEXP (src, 1) == pc_rtx)
+    {
+      rtx cond = XEXP (src, 0);
+      enum rtx_code revcode = reversed_comparison_code (cond, insn);
+
+      if (revcode == UNKNOWN)
+	return 0;
+
+      if (rev)
+	*rev = true;
+      return cond;
+    }
+
+  return 0;
+}
+
+/* True when we can find a condition under which INSN is executed.  */
+static bool
+sched_has_condition_p (const_rtx insn)
+{
+  return !! sched_get_condition_with_rev (insn, NULL);
+}
+
+
+
+/* Return nonzero if conditions COND1 and COND2 can never be both true.  */
+static int
+conditions_mutex_p (const_rtx cond1, const_rtx cond2, bool rev1, bool rev2)
+{
+  if (COMPARISON_P (cond1)
+      && COMPARISON_P (cond2)
+      && GET_CODE (cond1) ==
+	  (rev1==rev2
+	  ? reversed_comparison_code (cond2, NULL)
+	  : GET_CODE (cond2))
+      && XEXP (cond1, 0) == XEXP (cond2, 0)
+      && XEXP (cond1, 1) == XEXP (cond2, 1))
+    return 1;
+  return 0;
+}
+
+/* Return true if insn1 and insn2 can never depend on one another because
+   the conditions under which they are executed are mutually exclusive.  */
+bool
+sched_insns_conditions_mutex_p (const_rtx insn1, const_rtx insn2)
+{
+  rtx cond1, cond2;
+  bool rev1 = false, rev2 = false;
+
+  /* df doesn't handle conditional lifetimes entirely correctly;
+     calls mess up the conditional lifetimes.  */
+  if (!CALL_P (insn1) && !CALL_P (insn2))
+    {
+      cond1 = sched_get_condition_with_rev (insn1, &rev1);
+      cond2 = sched_get_condition_with_rev (insn2, &rev2);
+      if (cond1 && cond2
+	  && conditions_mutex_p (cond1, cond2, rev1, rev2)
+	  /* Make sure first instruction doesn't affect condition of second
+	     instruction if switched.  */
+	  && !modified_in_p (cond1, insn2)
+	  /* Make sure second instruction doesn't affect condition of first
+	     instruction if switched.  */
+	  && !modified_in_p (cond2, insn1))
+	return true;
+    }
+  return false;
+}
+
+
+/* Return true if INSN can potentially be speculated with type DS.  */
+bool
+sched_insn_is_legitimate_for_speculation_p (const_rtx insn, ds_t ds)
+{
+  if (HAS_INTERNAL_DEP (insn))
+    return false;
+
+  if (!NONJUMP_INSN_P (insn))
+    return false;
+
+  if (SCHED_GROUP_P (insn))
+    return false;
+
+  if (IS_SPECULATION_CHECK_P (CONST_CAST_RTX (insn)))
+    return false;
+
+  if (side_effects_p (PATTERN (insn)))
+    return false;
+
+  if (ds & BE_IN_SPEC)
+    /* The following instructions, which depend on a speculatively scheduled
+       instruction, cannot be speculatively scheduled along.  */
+    {
+      if (may_trap_p (PATTERN (insn)))
+	/* If instruction might trap, it cannot be speculatively scheduled.
+	   For control speculation it's obvious why and for data speculation
+	   it's because the insn might get wrong input if speculation
+	   wasn't successful.  */
+	return false;
+
+      if ((ds & BE_IN_DATA)
+	  && sched_has_condition_p (insn))
+	/* If this is a predicated instruction, then it cannot be
+	   speculatively scheduled.  See PR35659.  */
+	return false;
+    }
+
+  return true;
+}
+
+/* Initialize LIST_PTR to point to one of the lists present in TYPES_PTR,
+   initialize RESOLVED_P_PTR with true if that list consists of resolved deps,
+   and remove the type of returned [through LIST_PTR] list from TYPES_PTR.
+   This function is used to switch sd_iterator to the next list.
+   !!! For internal use only.  Might consider moving it to sched-int.h.  */
+void
+sd_next_list (const_rtx insn, sd_list_types_def *types_ptr,
+	      deps_list_t *list_ptr, bool *resolved_p_ptr)
+{
+  sd_list_types_def types = *types_ptr;
+
+  if (types & SD_LIST_HARD_BACK)
+    {
+      *list_ptr = INSN_HARD_BACK_DEPS (insn);
+      *resolved_p_ptr = false;
+      *types_ptr = types & ~SD_LIST_HARD_BACK;
+    }
+  else if (types & SD_LIST_SPEC_BACK)
+    {
+      *list_ptr = INSN_SPEC_BACK_DEPS (insn);
+      *resolved_p_ptr = false;
+      *types_ptr = types & ~SD_LIST_SPEC_BACK;
+    }
+  else if (types & SD_LIST_FORW)
+    {
+      *list_ptr = INSN_FORW_DEPS (insn);
+      *resolved_p_ptr = false;
+      *types_ptr = types & ~SD_LIST_FORW;
+    }
+  else if (types & SD_LIST_RES_BACK)
+    {
+      *list_ptr = INSN_RESOLVED_BACK_DEPS (insn);
+      *resolved_p_ptr = true;
+      *types_ptr = types & ~SD_LIST_RES_BACK;
+    }
+  else if (types & SD_LIST_RES_FORW)
+    {
+      *list_ptr = INSN_RESOLVED_FORW_DEPS (insn);
+      *resolved_p_ptr = true;
+      *types_ptr = types & ~SD_LIST_RES_FORW;
+    }
+  else
+    {
+      *list_ptr = NULL;
+      *resolved_p_ptr = false;
+      *types_ptr = SD_LIST_NONE;
+    }
+}
+
+/* Return the summary size of INSN's lists defined by LIST_TYPES.  */
+int
+sd_lists_size (const_rtx insn, sd_list_types_def list_types)
+{
+  int size = 0;
+
+  while (list_types != SD_LIST_NONE)
+    {
+      deps_list_t list;
+      bool resolved_p;
+
+      sd_next_list (insn, &list_types, &list, &resolved_p);
+      size += DEPS_LIST_N_LINKS (list);
+    }
+
+  return size;
+}
+
+/* Return true if INSN's lists defined by LIST_TYPES are all empty.  */
+bool
+sd_lists_empty_p (const_rtx insn, sd_list_types_def list_types)
+{
+  return sd_lists_size (insn, list_types) == 0;
+}
+
+/* Initialize data for INSN.  */
+void
+sd_init_insn (rtx insn)
+{
+  INSN_HARD_BACK_DEPS (insn) = create_deps_list ();
+  INSN_SPEC_BACK_DEPS (insn) = create_deps_list ();
+  INSN_RESOLVED_BACK_DEPS (insn) = create_deps_list ();
+  INSN_FORW_DEPS (insn) = create_deps_list ();
+  INSN_RESOLVED_FORW_DEPS (insn) = create_deps_list ();
+
+  /* ??? It would be nice to allocate dependency caches here.  */
+}
+
+/* Free data for INSN.  */
+void
+sd_finish_insn (rtx insn)
+{
+  /* ??? It would be nice to deallocate dependency caches here.  */
+
+  free_deps_list (INSN_HARD_BACK_DEPS (insn));
+  INSN_HARD_BACK_DEPS (insn) = NULL;
+
+  free_deps_list (INSN_SPEC_BACK_DEPS (insn));
+  INSN_SPEC_BACK_DEPS (insn) = NULL;
+
+  free_deps_list (INSN_RESOLVED_BACK_DEPS (insn));
+  INSN_RESOLVED_BACK_DEPS (insn) = NULL;
+
+  free_deps_list (INSN_FORW_DEPS (insn));
+  INSN_FORW_DEPS (insn) = NULL;
+
+  free_deps_list (INSN_RESOLVED_FORW_DEPS (insn));
+  INSN_RESOLVED_FORW_DEPS (insn) = NULL;
+}
+
+/* Find a dependency between producer PRO and consumer CON.
+   Search through resolved dependency lists if RESOLVED_P is true.
+   If no such dependency is found return NULL,
+   otherwise return the dependency and initialize SD_IT_PTR [if it is nonnull]
+   with an iterator pointing to it.  */
+static dep_t
+sd_find_dep_between_no_cache (rtx pro, rtx con, bool resolved_p,
+			      sd_iterator_def *sd_it_ptr)
+{
+  sd_list_types_def pro_list_type;
+  sd_list_types_def con_list_type;
+  sd_iterator_def sd_it;
+  dep_t dep;
+  bool found_p = false;
+
+  if (resolved_p)
+    {
+      pro_list_type = SD_LIST_RES_FORW;
+      con_list_type = SD_LIST_RES_BACK;
+    }
+  else
+    {
+      pro_list_type = SD_LIST_FORW;
+      con_list_type = SD_LIST_BACK;
+    }
+
+  /* Walk through either back list of INSN or forw list of ELEM
+     depending on which one is shorter.  */
+  if (sd_lists_size (con, con_list_type) < sd_lists_size (pro, pro_list_type))
+    {
+      /* Find the dep_link with producer PRO in consumer's back_deps.  */
+      FOR_EACH_DEP (con, con_list_type, sd_it, dep)
+	if (DEP_PRO (dep) == pro)
+	  {
+	    found_p = true;
+	    break;
+	  }
+    }
+  else
+    {
+      /* Find the dep_link with consumer CON in producer's forw_deps.  */
+      FOR_EACH_DEP (pro, pro_list_type, sd_it, dep)
+	if (DEP_CON (dep) == con)
+	  {
+	    found_p = true;
+	    break;
+	  }
+    }
+
+  if (found_p)
+    {
+      if (sd_it_ptr != NULL)
+	*sd_it_ptr = sd_it;
+
+      return dep;
+    }
+
+  return NULL;
+}
+
+/* Find a dependency between producer PRO and consumer CON.
+   Use dependency [if available] to check if dependency is present at all.
+   Search through resolved dependency lists if RESOLVED_P is true.
+   If the dependency or NULL if none found.  */
+dep_t
+sd_find_dep_between (rtx pro, rtx con, bool resolved_p)
+{
+  if (true_dependency_cache != NULL)
+    /* Avoiding the list walk below can cut compile times dramatically
+       for some code.  */
+    {
+      int elem_luid = INSN_LUID (pro);
+      int insn_luid = INSN_LUID (con);
+
+      gcc_assert (output_dependency_cache != NULL
+		  && anti_dependency_cache != NULL);
+
+      if (!bitmap_bit_p (&true_dependency_cache[insn_luid], elem_luid)
+	  && !bitmap_bit_p (&output_dependency_cache[insn_luid], elem_luid)
+	  && !bitmap_bit_p (&anti_dependency_cache[insn_luid], elem_luid))
+	return NULL;
+    }
+
+  return sd_find_dep_between_no_cache (pro, con, resolved_p, NULL);
+}
+
+/* Add or update  a dependence described by DEP.
+   MEM1 and MEM2, if non-null, correspond to memory locations in case of
+   data speculation.
+
+   The function returns a value indicating if an old entry has been changed
+   or a new entry has been added to insn's backward deps.
+
+   This function merely checks if producer and consumer is the same insn
+   and doesn't create a dep in this case.  Actual manipulation of
+   dependence data structures is performed in add_or_update_dep_1.  */
+static enum DEPS_ADJUST_RESULT
+maybe_add_or_update_dep_1 (dep_t dep, bool resolved_p, rtx mem1, rtx mem2)
+{
+  rtx elem = DEP_PRO (dep);
+  rtx insn = DEP_CON (dep);
+
+  gcc_assert (INSN_P (insn) && INSN_P (elem));
+
+  /* Don't depend an insn on itself.  */
+  if (insn == elem)
+    {
+      if (sched_deps_info->generate_spec_deps)
+        /* INSN has an internal dependence, which we can't overcome.  */
+        HAS_INTERNAL_DEP (insn) = 1;
+
+      return DEP_NODEP;
+    }
+
+  return add_or_update_dep_1 (dep, resolved_p, mem1, mem2);
+}
+
+/* Ask dependency caches what needs to be done for dependence DEP.
+   Return DEP_CREATED if new dependence should be created and there is no
+   need to try to find one searching the dependencies lists.
+   Return DEP_PRESENT if there already is a dependence described by DEP and
+   hence nothing is to be done.
+   Return DEP_CHANGED if there already is a dependence, but it should be
+   updated to incorporate additional information from DEP.  */
+static enum DEPS_ADJUST_RESULT
+ask_dependency_caches (dep_t dep)
+{
+  int elem_luid = INSN_LUID (DEP_PRO (dep));
+  int insn_luid = INSN_LUID (DEP_CON (dep));
+
+  gcc_assert (true_dependency_cache != NULL
+	      && output_dependency_cache != NULL
+	      && anti_dependency_cache != NULL);
+
+  if (!(current_sched_info->flags & USE_DEPS_LIST))
+    {          
+      enum reg_note present_dep_type;
+
+      if (bitmap_bit_p (&true_dependency_cache[insn_luid], elem_luid))
+	present_dep_type = REG_DEP_TRUE;
+      else if (bitmap_bit_p (&output_dependency_cache[insn_luid], elem_luid))
+	present_dep_type = REG_DEP_OUTPUT;
+      else if (bitmap_bit_p (&anti_dependency_cache[insn_luid], elem_luid))
+	present_dep_type = REG_DEP_ANTI;
+      else
+	/* There is no existing dep so it should be created.  */
+	return DEP_CREATED;
+
+      if ((int) DEP_TYPE (dep) >= (int) present_dep_type)
+	/* DEP does not add anything to the existing dependence.  */
+	return DEP_PRESENT;
+    }
+  else
+    {      
+      ds_t present_dep_types = 0;
+          
+      if (bitmap_bit_p (&true_dependency_cache[insn_luid], elem_luid))
+	present_dep_types |= DEP_TRUE;
+      if (bitmap_bit_p (&output_dependency_cache[insn_luid], elem_luid))
+	present_dep_types |= DEP_OUTPUT;
+      if (bitmap_bit_p (&anti_dependency_cache[insn_luid], elem_luid))
+	present_dep_types |= DEP_ANTI;
+
+      if (present_dep_types == 0)
+	/* There is no existing dep so it should be created.  */
+	return DEP_CREATED;
+
+      if (!(current_sched_info->flags & DO_SPECULATION)
+	  || !bitmap_bit_p (&spec_dependency_cache[insn_luid], elem_luid))
+	{
+	  if ((present_dep_types | (DEP_STATUS (dep) & DEP_TYPES))
+	      == present_dep_types)
+	    /* DEP does not add anything to the existing dependence.  */
+	    return DEP_PRESENT;
+	}
+      else
+	{
+	  /* Only true dependencies can be data speculative and
+	     only anti dependencies can be control speculative.  */
+	  gcc_assert ((present_dep_types & (DEP_TRUE | DEP_ANTI))
+		      == present_dep_types);
+
+	  /* if (DEP is SPECULATIVE) then
+	     ..we should update DEP_STATUS
+	     else
+	     ..we should reset existing dep to non-speculative.  */
+	}
+    }
+
+  return DEP_CHANGED;
+}
+
+/* Set dependency caches according to DEP.  */
+static void
+set_dependency_caches (dep_t dep)
+{
+  int elem_luid = INSN_LUID (DEP_PRO (dep));
+  int insn_luid = INSN_LUID (DEP_CON (dep));
+
+  if (!(current_sched_info->flags & USE_DEPS_LIST))
+    {
+      switch (DEP_TYPE (dep))
+	{
+	case REG_DEP_TRUE:
+	  bitmap_set_bit (&true_dependency_cache[insn_luid], elem_luid);
+	  break;
+
+	case REG_DEP_OUTPUT:
+	  bitmap_set_bit (&output_dependency_cache[insn_luid], elem_luid);
+	  break;
+
+	case REG_DEP_ANTI:
+	  bitmap_set_bit (&anti_dependency_cache[insn_luid], elem_luid);
+	  break;
+
+	default:
+	  gcc_unreachable ();
+	}
+    }
+  else
+    {
+      ds_t ds = DEP_STATUS (dep);
+
+      if (ds & DEP_TRUE)
+	bitmap_set_bit (&true_dependency_cache[insn_luid], elem_luid);
+      if (ds & DEP_OUTPUT)
+	bitmap_set_bit (&output_dependency_cache[insn_luid], elem_luid);
+      if (ds & DEP_ANTI)
+	bitmap_set_bit (&anti_dependency_cache[insn_luid], elem_luid);
+
+      if (ds & SPECULATIVE)
+	{
+	  gcc_assert (current_sched_info->flags & DO_SPECULATION);
+	  bitmap_set_bit (&spec_dependency_cache[insn_luid], elem_luid);
+	}
+    }
+}
+
+/* Type of dependence DEP have changed from OLD_TYPE.  Update dependency
+   caches accordingly.  */
+static void
+update_dependency_caches (dep_t dep, enum reg_note old_type)
+{
+  int elem_luid = INSN_LUID (DEP_PRO (dep));
+  int insn_luid = INSN_LUID (DEP_CON (dep));
+
+  /* Clear corresponding cache entry because type of the link
+     may have changed.  Keep them if we use_deps_list.  */
+  if (!(current_sched_info->flags & USE_DEPS_LIST))
+    {
+      switch (old_type)
+	{
+	case REG_DEP_OUTPUT:
+	  bitmap_clear_bit (&output_dependency_cache[insn_luid], elem_luid);
+	  break;
+
+	case REG_DEP_ANTI:
+	  bitmap_clear_bit (&anti_dependency_cache[insn_luid], elem_luid);
+	  break;
+
+	default:
+	  gcc_unreachable ();                        
+	}
+    }
+
+  set_dependency_caches (dep);
+}
+
+/* Convert a dependence pointed to by SD_IT to be non-speculative.  */
+static void
+change_spec_dep_to_hard (sd_iterator_def sd_it)
+{
+  dep_node_t node = DEP_LINK_NODE (*sd_it.linkp);
+  dep_link_t link = DEP_NODE_BACK (node);
+  dep_t dep = DEP_NODE_DEP (node);
+  rtx elem = DEP_PRO (dep);
+  rtx insn = DEP_CON (dep);
+
+  move_dep_link (link, INSN_SPEC_BACK_DEPS (insn), INSN_HARD_BACK_DEPS (insn));
+
+  DEP_STATUS (dep) &= ~SPECULATIVE;
+
+  if (true_dependency_cache != NULL)
+    /* Clear the cache entry.  */
+    bitmap_clear_bit (&spec_dependency_cache[INSN_LUID (insn)],
+		      INSN_LUID (elem));
+}
+
+/* Update DEP to incorporate information from NEW_DEP.
+   SD_IT points to DEP in case it should be moved to another list.
+   MEM1 and MEM2, if nonnull, correspond to memory locations in case if
+   data-speculative dependence should be updated.  */
+static enum DEPS_ADJUST_RESULT
+update_dep (dep_t dep, dep_t new_dep,
+	    sd_iterator_def sd_it ATTRIBUTE_UNUSED,
+	    rtx mem1 ATTRIBUTE_UNUSED,
+	    rtx mem2 ATTRIBUTE_UNUSED)
+{
+  enum DEPS_ADJUST_RESULT res = DEP_PRESENT;
+  enum reg_note old_type = DEP_TYPE (dep);
+
+  /* If this is a more restrictive type of dependence than the
+     existing one, then change the existing dependence to this
+     type.  */
+  if ((int) DEP_TYPE (new_dep) < (int) old_type)
+    {
+      DEP_TYPE (dep) = DEP_TYPE (new_dep);
+      res = DEP_CHANGED;
+    }
+
+  if (current_sched_info->flags & USE_DEPS_LIST)
+    /* Update DEP_STATUS.  */
+    {
+      ds_t dep_status = DEP_STATUS (dep);
+      ds_t ds = DEP_STATUS (new_dep);
+      ds_t new_status = ds | dep_status;
+
+      if (new_status & SPECULATIVE)
+	/* Either existing dep or a dep we're adding or both are
+	   speculative.  */
+	{
+	  if (!(ds & SPECULATIVE)
+	      || !(dep_status & SPECULATIVE))
+	    /* The new dep can't be speculative.  */
+	    {
+	      new_status &= ~SPECULATIVE;
+
+	      if (dep_status & SPECULATIVE)
+		/* The old dep was speculative, but now it
+		   isn't.  */
+		change_spec_dep_to_hard (sd_it);
+	    }
+	  else
+	    {
+	      /* Both are speculative.  Merge probabilities.  */
+	      if (mem1 != NULL)
+		{
+		  dw_t dw;
+
+		  dw = estimate_dep_weak (mem1, mem2);
+		  ds = set_dep_weak (ds, BEGIN_DATA, dw);
+		}
+							 
+	      new_status = ds_merge (dep_status, ds);
+	    }
+	}
+
+      ds = new_status;
+
+      if (dep_status != ds)
+	{
+	  DEP_STATUS (dep) = ds;
+	  res = DEP_CHANGED;
+	}
+    }
+
+  if (true_dependency_cache != NULL
+      && res == DEP_CHANGED)
+    update_dependency_caches (dep, old_type);
+
+  return res;
+}
+
+/* Add or update  a dependence described by DEP.
+   MEM1 and MEM2, if non-null, correspond to memory locations in case of
+   data speculation.
+
+   The function returns a value indicating if an old entry has been changed
+   or a new entry has been added to insn's backward deps or nothing has
+   been updated at all.  */
+static enum DEPS_ADJUST_RESULT
+add_or_update_dep_1 (dep_t new_dep, bool resolved_p,
+		     rtx mem1 ATTRIBUTE_UNUSED, rtx mem2 ATTRIBUTE_UNUSED)
+{
+  bool maybe_present_p = true;
+  bool present_p = false;
+
+  gcc_assert (INSN_P (DEP_PRO (new_dep)) && INSN_P (DEP_CON (new_dep))
+	      && DEP_PRO (new_dep) != DEP_CON (new_dep));
+  
+#ifdef ENABLE_CHECKING
+  check_dep (new_dep, mem1 != NULL);
+#endif
+
+  if (true_dependency_cache != NULL)
+    {
+      switch (ask_dependency_caches (new_dep))
+	{
+	case DEP_PRESENT:
+	  return DEP_PRESENT;
+
+	case DEP_CHANGED:
+	  maybe_present_p = true;
+	  present_p = true;
+	  break;
+
+	case DEP_CREATED:
+	  maybe_present_p = false;
+	  present_p = false;
+	  break;
+
+	default:
+	  gcc_unreachable ();
+	  break;
+	}
+    }
+
+  /* Check that we don't already have this dependence.  */
+  if (maybe_present_p)
+    {
+      dep_t present_dep;
+      sd_iterator_def sd_it;
+
+      gcc_assert (true_dependency_cache == NULL || present_p);
+
+      present_dep = sd_find_dep_between_no_cache (DEP_PRO (new_dep),
+						  DEP_CON (new_dep),
+						  resolved_p, &sd_it);
+
+      if (present_dep != NULL)
+	/* We found an existing dependency between ELEM and INSN.  */
+	return update_dep (present_dep, new_dep, sd_it, mem1, mem2);
+      else
+	/* We didn't find a dep, it shouldn't present in the cache.  */
+	gcc_assert (!present_p);
+    }
+
+  /* Might want to check one level of transitivity to save conses.
+     This check should be done in maybe_add_or_update_dep_1.
+     Since we made it to add_or_update_dep_1, we must create
+     (or update) a link.  */
+
+  if (mem1 != NULL_RTX)
+    {
+      gcc_assert (sched_deps_info->generate_spec_deps);
+      DEP_STATUS (new_dep) = set_dep_weak (DEP_STATUS (new_dep), BEGIN_DATA,
+					   estimate_dep_weak (mem1, mem2));
+    }
+
+  sd_add_dep (new_dep, resolved_p);
+  
+  return DEP_CREATED;
+}
+
+/* Initialize BACK_LIST_PTR with consumer's backward list and
+   FORW_LIST_PTR with producer's forward list.  If RESOLVED_P is true
+   initialize with lists that hold resolved deps.  */
+static void
+get_back_and_forw_lists (dep_t dep, bool resolved_p,
+			 deps_list_t *back_list_ptr,
+			 deps_list_t *forw_list_ptr)
+{
+  rtx con = DEP_CON (dep);
+
+  if (!resolved_p)
+    {
+      if ((current_sched_info->flags & DO_SPECULATION)
+	  && (DEP_STATUS (dep) & SPECULATIVE))
+	*back_list_ptr = INSN_SPEC_BACK_DEPS (con);
+      else
+	*back_list_ptr = INSN_HARD_BACK_DEPS (con);
+
+      *forw_list_ptr = INSN_FORW_DEPS (DEP_PRO (dep));
+    }
+  else
+    {
+      *back_list_ptr = INSN_RESOLVED_BACK_DEPS (con);
+      *forw_list_ptr = INSN_RESOLVED_FORW_DEPS (DEP_PRO (dep));
+    }
+}
+
+/* Add dependence described by DEP.
+   If RESOLVED_P is true treat the dependence as a resolved one.  */
+void
+sd_add_dep (dep_t dep, bool resolved_p)
+{
+  dep_node_t n = create_dep_node ();
+  deps_list_t con_back_deps;
+  deps_list_t pro_forw_deps;
+  rtx elem = DEP_PRO (dep);
+  rtx insn = DEP_CON (dep);
+
+  gcc_assert (INSN_P (insn) && INSN_P (elem) && insn != elem);
+
+  if ((current_sched_info->flags & DO_SPECULATION)
+      && !sched_insn_is_legitimate_for_speculation_p (insn, DEP_STATUS (dep)))
+    DEP_STATUS (dep) &= ~SPECULATIVE;
+
+  copy_dep (DEP_NODE_DEP (n), dep);
+
+  get_back_and_forw_lists (dep, resolved_p, &con_back_deps, &pro_forw_deps);
+
+  add_to_deps_list (DEP_NODE_BACK (n), con_back_deps);
+
+#ifdef ENABLE_CHECKING
+  check_dep (dep, false);
+#endif
+
+  add_to_deps_list (DEP_NODE_FORW (n), pro_forw_deps);
+
+  /* If we are adding a dependency to INSN's LOG_LINKs, then note that
+     in the bitmap caches of dependency information.  */
+  if (true_dependency_cache != NULL)
+    set_dependency_caches (dep);
+}
+
+/* Add or update backward dependence between INSN and ELEM
+   with given type DEP_TYPE and dep_status DS.
+   This function is a convenience wrapper.  */
+enum DEPS_ADJUST_RESULT
+sd_add_or_update_dep (dep_t dep, bool resolved_p)
+{
+  return add_or_update_dep_1 (dep, resolved_p, NULL_RTX, NULL_RTX);
+}
+
+/* Resolved dependence pointed to by SD_IT.
+   SD_IT will advance to the next element.  */
+void
+sd_resolve_dep (sd_iterator_def sd_it)
+{
+  dep_node_t node = DEP_LINK_NODE (*sd_it.linkp);
+  dep_t dep = DEP_NODE_DEP (node);
+  rtx pro = DEP_PRO (dep);
+  rtx con = DEP_CON (dep);
+
+  if ((current_sched_info->flags & DO_SPECULATION)
+      && (DEP_STATUS (dep) & SPECULATIVE))
+    move_dep_link (DEP_NODE_BACK (node), INSN_SPEC_BACK_DEPS (con),
+		   INSN_RESOLVED_BACK_DEPS (con));
+  else
+    move_dep_link (DEP_NODE_BACK (node), INSN_HARD_BACK_DEPS (con),
+		   INSN_RESOLVED_BACK_DEPS (con));
+
+  move_dep_link (DEP_NODE_FORW (node), INSN_FORW_DEPS (pro),
+		 INSN_RESOLVED_FORW_DEPS (pro));
+}
+
+/* Make TO depend on all the FROM's producers.
+   If RESOLVED_P is true add dependencies to the resolved lists.  */
+void
+sd_copy_back_deps (rtx to, rtx from, bool resolved_p)
+{
+  sd_list_types_def list_type;
+  sd_iterator_def sd_it;
+  dep_t dep;
+
+  list_type = resolved_p ? SD_LIST_RES_BACK : SD_LIST_BACK;
+
+  FOR_EACH_DEP (from, list_type, sd_it, dep)
+    {
+      dep_def _new_dep, *new_dep = &_new_dep;
+
+      copy_dep (new_dep, dep);
+      DEP_CON (new_dep) = to;
+      sd_add_dep (new_dep, resolved_p);
+    }
+}
+
+/* Remove a dependency referred to by SD_IT.
+   SD_IT will point to the next dependence after removal.  */
+void
+sd_delete_dep (sd_iterator_def sd_it)
+{
+  dep_node_t n = DEP_LINK_NODE (*sd_it.linkp);
+  dep_t dep = DEP_NODE_DEP (n);
+  rtx pro = DEP_PRO (dep);
+  rtx con = DEP_CON (dep);
+  deps_list_t con_back_deps;
+  deps_list_t pro_forw_deps;
+
+  if (true_dependency_cache != NULL)
+    {
+      int elem_luid = INSN_LUID (pro);
+      int insn_luid = INSN_LUID (con);
+
+      bitmap_clear_bit (&true_dependency_cache[insn_luid], elem_luid);
+      bitmap_clear_bit (&anti_dependency_cache[insn_luid], elem_luid);
+      bitmap_clear_bit (&output_dependency_cache[insn_luid], elem_luid);
+
+      if (current_sched_info->flags & DO_SPECULATION)
+	bitmap_clear_bit (&spec_dependency_cache[insn_luid], elem_luid);
+    }
+
+  get_back_and_forw_lists (dep, sd_it.resolved_p,
+			   &con_back_deps, &pro_forw_deps);
+
+  remove_from_deps_list (DEP_NODE_BACK (n), con_back_deps);
+  remove_from_deps_list (DEP_NODE_FORW (n), pro_forw_deps);
+
+  delete_dep_node (n);
+}
+
+/* Dump size of the lists.  */
+#define DUMP_LISTS_SIZE (2)
+
+/* Dump dependencies of the lists.  */
+#define DUMP_LISTS_DEPS (4)
+
+/* Dump all information about the lists.  */
+#define DUMP_LISTS_ALL (DUMP_LISTS_SIZE | DUMP_LISTS_DEPS)
+
+/* Dump deps_lists of INSN specified by TYPES to DUMP.
+   FLAGS is a bit mask specifying what information about the lists needs
+   to be printed.
+   If FLAGS has the very first bit set, then dump all information about
+   the lists and propagate this bit into the callee dump functions.  */
+static void
+dump_lists (FILE *dump, rtx insn, sd_list_types_def types, int flags)
+{
+  sd_iterator_def sd_it;
+  dep_t dep;
+  int all;
+
+  all = (flags & 1);
+
+  if (all)
+    flags |= DUMP_LISTS_ALL;
+
+  fprintf (dump, "[");
+
+  if (flags & DUMP_LISTS_SIZE)
+    fprintf (dump, "%d; ", sd_lists_size (insn, types));
+
+  if (flags & DUMP_LISTS_DEPS)
+    {
+      FOR_EACH_DEP (insn, types, sd_it, dep)
+	{
+	  dump_dep (dump, dep, dump_dep_flags | all);
+	  fprintf (dump, " ");
+	}
+    }
+}
+
+/* Dump all information about deps_lists of INSN specified by TYPES
+   to STDERR.  */
+void
+sd_debug_lists (rtx insn, sd_list_types_def types)
+{
+  dump_lists (stderr, insn, types, 1);
+  fprintf (stderr, "\n");
+}
+
+/* A convenience wrapper to operate on an entire list.  */
+
+static void
+add_dependence_list (rtx insn, rtx list, int uncond, enum reg_note dep_type)
+{
+  for (; list; list = XEXP (list, 1))
+    {
+      if (uncond || ! sched_insns_conditions_mutex_p (insn, XEXP (list, 0)))
+	add_dependence (insn, XEXP (list, 0), dep_type);
+    }
+}
+
+/* Similar, but free *LISTP at the same time, when the context 
+   is not readonly.  */
+
+static void
+add_dependence_list_and_free (struct deps *deps, rtx insn, rtx *listp, 
+                              int uncond, enum reg_note dep_type)
+{
+  rtx list, next;
+
+  if (deps->readonly)
+    {
+      add_dependence_list (insn, *listp, uncond, dep_type);
+      return;
+    }
+
+  for (list = *listp, *listp = NULL; list ; list = next)
+    {
+      next = XEXP (list, 1);
+      if (uncond || ! sched_insns_conditions_mutex_p (insn, XEXP (list, 0)))
+	add_dependence (insn, XEXP (list, 0), dep_type);
+      free_INSN_LIST_node (list);
+    }
+}
+
+/* Remove all occurences of INSN from LIST.  Return the number of 
+   occurences removed.  */
+
+static int
+remove_from_dependence_list (rtx insn, rtx* listp)
+{
+  int removed = 0;
+  
+  while (*listp)
+    {
+      if (XEXP (*listp, 0) == insn)
+        {
+          remove_free_INSN_LIST_node (listp);
+          removed++;
+          continue;
+        }
+      
+      listp = &XEXP (*listp, 1);
+    }
+  
+  return removed;
+}
+
+/* Same as above, but process two lists at once.  */
+static int 
+remove_from_both_dependence_lists (rtx insn, rtx *listp, rtx *exprp)
+{
+  int removed = 0;
+  
+  while (*listp)
+    {
+      if (XEXP (*listp, 0) == insn)
+        {
+          remove_free_INSN_LIST_node (listp);
+          remove_free_EXPR_LIST_node (exprp);
+          removed++;
+          continue;
+        }
+      
+      listp = &XEXP (*listp, 1);
+      exprp = &XEXP (*exprp, 1);
+    }
+  
+  return removed;
+}
+
+/* Clear all dependencies for an insn.  */
+static void
+delete_all_dependences (rtx insn)
+{
+  sd_iterator_def sd_it;
+  dep_t dep;
+
+  /* The below cycle can be optimized to clear the caches and back_deps
+     in one call but that would provoke duplication of code from
+     delete_dep ().  */
+
+  for (sd_it = sd_iterator_start (insn, SD_LIST_BACK);
+       sd_iterator_cond (&sd_it, &dep);)
+    sd_delete_dep (sd_it);
+}
+
+/* All insns in a scheduling group except the first should only have
+   dependencies on the previous insn in the group.  So we find the
+   first instruction in the scheduling group by walking the dependence
+   chains backwards. Then we add the dependencies for the group to
+   the previous nonnote insn.  */
+
+static void
+fixup_sched_groups (rtx insn)
+{
+  sd_iterator_def sd_it;
+  dep_t dep;
+  rtx prev_nonnote;
+
+  FOR_EACH_DEP (insn, SD_LIST_BACK, sd_it, dep)
+    {
+      rtx i = insn;
+      rtx pro = DEP_PRO (dep);
+
+      do
+	{
+	  i = prev_nonnote_insn (i);
+
+	  if (pro == i)
+	    goto next_link;
+	} while (SCHED_GROUP_P (i));
+
+      if (! sched_insns_conditions_mutex_p (i, pro))
+	add_dependence (i, pro, DEP_TYPE (dep));
+    next_link:;
+    }
+
+  delete_all_dependences (insn);
+
+  prev_nonnote = prev_nonnote_insn (insn);
+  if (BLOCK_FOR_INSN (insn) == BLOCK_FOR_INSN (prev_nonnote)
+      && ! sched_insns_conditions_mutex_p (insn, prev_nonnote))
+    add_dependence (insn, prev_nonnote, REG_DEP_ANTI);
+}
+
+/* Process an insn's memory dependencies.  There are four kinds of
+   dependencies:
+
+   (0) read dependence: read follows read
+   (1) true dependence: read follows write
+   (2) output dependence: write follows write
+   (3) anti dependence: write follows read
+
+   We are careful to build only dependencies which actually exist, and
+   use transitivity to avoid building too many links.  */
+
+/* Add an INSN and MEM reference pair to a pending INSN_LIST and MEM_LIST.
+   The MEM is a memory reference contained within INSN, which we are saving
+   so that we can do memory aliasing on it.  */
+
+static void
+add_insn_mem_dependence (struct deps *deps, bool read_p,
+			 rtx insn, rtx mem)
+{
+  rtx *insn_list;
+  rtx *mem_list;
+  rtx link;
+
+  gcc_assert (!deps->readonly);
+  if (read_p)
+    {
+      insn_list = &deps->pending_read_insns;
+      mem_list = &deps->pending_read_mems;
+      deps->pending_read_list_length++;
+    }
+  else
+    {
+      insn_list = &deps->pending_write_insns;
+      mem_list = &deps->pending_write_mems;
+      deps->pending_write_list_length++;
+    }
+
+  link = alloc_INSN_LIST (insn, *insn_list);
+  *insn_list = link;
+
+  if (sched_deps_info->use_cselib)
+    {
+      mem = shallow_copy_rtx (mem);
+      XEXP (mem, 0) = cselib_subst_to_values (XEXP (mem, 0));
+    }
+  link = alloc_EXPR_LIST (VOIDmode, canon_rtx (mem), *mem_list);
+  *mem_list = link;
+}
+
+/* Make a dependency between every memory reference on the pending lists
+   and INSN, thus flushing the pending lists.  FOR_READ is true if emitting
+   dependencies for a read operation, similarly with FOR_WRITE.  */
+
+static void
+flush_pending_lists (struct deps *deps, rtx insn, int for_read,
+		     int for_write)
+{
+  if (for_write)
+    {
+      add_dependence_list_and_free (deps, insn, &deps->pending_read_insns, 
+                                    1, REG_DEP_ANTI);
+      if (!deps->readonly)
+        {
+          free_EXPR_LIST_list (&deps->pending_read_mems);
+          deps->pending_read_list_length = 0;
+        }
+    }
+
+  add_dependence_list_and_free (deps, insn, &deps->pending_write_insns, 1,
+				for_read ? REG_DEP_ANTI : REG_DEP_OUTPUT);
+
+  add_dependence_list_and_free (deps, insn, 
+                                &deps->last_pending_memory_flush, 1,
+                                for_read ? REG_DEP_ANTI : REG_DEP_OUTPUT);
+  if (!deps->readonly)
+    {
+      free_EXPR_LIST_list (&deps->pending_write_mems);
+      deps->pending_write_list_length = 0;
+
+      deps->last_pending_memory_flush = alloc_INSN_LIST (insn, NULL_RTX);
+      deps->pending_flush_length = 1;
+    }
+}
+
+/* Instruction which dependencies we are analyzing.  */
+static rtx cur_insn = NULL_RTX;
+
+/* Implement hooks for haifa scheduler.  */
+
+static void
+haifa_start_insn (rtx insn)
+{
+  gcc_assert (insn && !cur_insn);
+
+  cur_insn = insn;
+}
+
+static void
+haifa_finish_insn (void)
+{
+  cur_insn = NULL;
+}
+
+void
+haifa_note_reg_set (int regno)
+{
+  SET_REGNO_REG_SET (reg_pending_sets, regno);
+}
+
+void
+haifa_note_reg_clobber (int regno)
+{
+  SET_REGNO_REG_SET (reg_pending_clobbers, regno);
+}
+
+void
+haifa_note_reg_use (int regno)
+{
+  SET_REGNO_REG_SET (reg_pending_uses, regno);
+}
+
+static void
+haifa_note_mem_dep (rtx mem, rtx pending_mem, rtx pending_insn, ds_t ds)
+{
+  if (!(ds & SPECULATIVE))
+    {
+      mem = NULL_RTX;
+      pending_mem = NULL_RTX;
+    }
+  else
+    gcc_assert (ds & BEGIN_DATA);
+
+  {
+    dep_def _dep, *dep = &_dep;
+    
+    init_dep_1 (dep, pending_insn, cur_insn, ds_to_dt (ds), 
+                current_sched_info->flags & USE_DEPS_LIST ? ds : -1);
+    maybe_add_or_update_dep_1 (dep, false, pending_mem, mem);
+  }
+
+}
+
+static void
+haifa_note_dep (rtx elem, ds_t ds)
+{
+  dep_def _dep;
+  dep_t dep = &_dep;
+
+  init_dep (dep, elem, cur_insn, ds_to_dt (ds));
+  maybe_add_or_update_dep_1 (dep, false, NULL_RTX, NULL_RTX);
+}
+
+static void
+note_reg_use (int r)
+{
+  if (sched_deps_info->note_reg_use)
+    sched_deps_info->note_reg_use (r);
+}
+
+static void
+note_reg_set (int r)
+{
+  if (sched_deps_info->note_reg_set)
+    sched_deps_info->note_reg_set (r);
+}
+
+static void
+note_reg_clobber (int r)
+{
+  if (sched_deps_info->note_reg_clobber)
+    sched_deps_info->note_reg_clobber (r);
+}
+
+static void
+note_mem_dep (rtx m1, rtx m2, rtx e, ds_t ds)
+{
+  if (sched_deps_info->note_mem_dep)
+    sched_deps_info->note_mem_dep (m1, m2, e, ds);
+}
+
+static void
+note_dep (rtx e, ds_t ds)
+{
+  if (sched_deps_info->note_dep)
+    sched_deps_info->note_dep (e, ds);
+}
+
+/* Return corresponding to DS reg_note.  */
+enum reg_note
+ds_to_dt (ds_t ds)
+{
+  if (ds & DEP_TRUE)
+    return REG_DEP_TRUE;
+  else if (ds & DEP_OUTPUT)
+    return REG_DEP_OUTPUT;
+  else
+    {
+      gcc_assert (ds & DEP_ANTI);
+      return REG_DEP_ANTI;
+    }
+}
+
+
+/* Internal variable for sched_analyze_[12] () functions.
+   If it is nonzero, this means that sched_analyze_[12] looks
+   at the most toplevel SET.  */
+static bool can_start_lhs_rhs_p;
+
+/* Extend reg info for the deps context DEPS given that 
+   we have just generated a register numbered REGNO.  */
+static void
+extend_deps_reg_info (struct deps *deps, int regno)
+{
+  int max_regno = regno + 1;
+
+  gcc_assert (!reload_completed);
+
+  /* In a readonly context, it would not hurt to extend info,
+     but it should not be needed.  */
+  if (reload_completed && deps->readonly)
+    {
+      deps->max_reg = max_regno;
+      return;
+    }
+
+  if (max_regno > deps->max_reg)
+    {
+      deps->reg_last = XRESIZEVEC (struct deps_reg, deps->reg_last, 
+                                   max_regno);
+      memset (&deps->reg_last[deps->max_reg],
+              0, (max_regno - deps->max_reg) 
+              * sizeof (struct deps_reg));
+      deps->max_reg = max_regno;
+    }
+}
+
+/* Extends REG_INFO_P if needed.  */
+void
+maybe_extend_reg_info_p (void)
+{
+  /* Extend REG_INFO_P, if needed.  */
+  if ((unsigned int)max_regno - 1 >= reg_info_p_size)
+    {
+      size_t new_reg_info_p_size = max_regno + 128;
+
+      gcc_assert (!reload_completed && sel_sched_p ());
+
+      reg_info_p = (struct reg_info_t *) xrecalloc (reg_info_p,
+                                                    new_reg_info_p_size,
+                                                    reg_info_p_size,
+                                                    sizeof (*reg_info_p));
+      reg_info_p_size = new_reg_info_p_size;
+    }
+}
+
+/* Analyze a single reference to register (reg:MODE REGNO) in INSN.
+   The type of the reference is specified by REF and can be SET,
+   CLOBBER, PRE_DEC, POST_DEC, PRE_INC, POST_INC or USE.  */
+
+static void
+sched_analyze_reg (struct deps *deps, int regno, enum machine_mode mode,
+		   enum rtx_code ref, rtx insn)
+{
+  /* We could emit new pseudos in renaming.  Extend the reg structures.  */
+  if (!reload_completed && sel_sched_p ()
+      && (regno >= max_reg_num () - 1 || regno >= deps->max_reg))
+    extend_deps_reg_info (deps, regno);
+
+  maybe_extend_reg_info_p ();
+
+  /* A hard reg in a wide mode may really be multiple registers.
+     If so, mark all of them just like the first.  */
+  if (regno < FIRST_PSEUDO_REGISTER)
+    {
+      int i = hard_regno_nregs[regno][mode];
+      if (ref == SET)
+	{
+	  while (--i >= 0)
+	    note_reg_set (regno + i);
+	}
+      else if (ref == USE)
+	{
+	  while (--i >= 0)
+	    note_reg_use (regno + i);
+	}
+      else
+	{
+	  while (--i >= 0)
+	    note_reg_clobber (regno + i);
+	}
+    }
+
+  /* ??? Reload sometimes emits USEs and CLOBBERs of pseudos that
+     it does not reload.  Ignore these as they have served their
+     purpose already.  */
+  else if (regno >= deps->max_reg)
+    {
+      enum rtx_code code = GET_CODE (PATTERN (insn));
+      gcc_assert (code == USE || code == CLOBBER);
+    }
+
+  else
+    {
+      if (ref == SET)
+	note_reg_set (regno);
+      else if (ref == USE)
+	note_reg_use (regno);
+      else
+	note_reg_clobber (regno);
+
+      /* Pseudos that are REG_EQUIV to something may be replaced
+	 by that during reloading.  We need only add dependencies for
+	the address in the REG_EQUIV note.  */
+      if (!reload_completed && get_reg_known_equiv_p (regno))
+	{
+	  rtx t = get_reg_known_value (regno);
+	  if (MEM_P (t))
+	    sched_analyze_2 (deps, XEXP (t, 0), insn);
+	}
+
+      /* Don't let it cross a call after scheduling if it doesn't
+	 already cross one.  */
+      if (REG_N_CALLS_CROSSED (regno) == 0)
+	{
+	  if (!deps->readonly 
+              && ref == USE)
+	    deps->sched_before_next_call
+	      = alloc_INSN_LIST (insn, deps->sched_before_next_call);
+	  else
+	    add_dependence_list (insn, deps->last_function_call, 1,
+				 REG_DEP_ANTI);
+	}
+    }
+}
+
+/* Analyze a single SET, CLOBBER, PRE_DEC, POST_DEC, PRE_INC or POST_INC
+   rtx, X, creating all dependencies generated by the write to the
+   destination of X, and reads of everything mentioned.  */
+
+static void
+sched_analyze_1 (struct deps *deps, rtx x, rtx insn)
+{
+  rtx dest = XEXP (x, 0);
+  enum rtx_code code = GET_CODE (x);
+  bool cslr_p = can_start_lhs_rhs_p;
+
+  can_start_lhs_rhs_p = false;
+
+  gcc_assert (dest);
+  if (dest == 0)
+    return;
+
+  if (cslr_p && sched_deps_info->start_lhs)
+    sched_deps_info->start_lhs (dest);
+
+  if (GET_CODE (dest) == PARALLEL)
+    {
+      int i;
+
+      for (i = XVECLEN (dest, 0) - 1; i >= 0; i--)
+	if (XEXP (XVECEXP (dest, 0, i), 0) != 0)
+	  sched_analyze_1 (deps,
+			   gen_rtx_CLOBBER (VOIDmode,
+					    XEXP (XVECEXP (dest, 0, i), 0)),
+			   insn);
+
+      if (cslr_p && sched_deps_info->finish_lhs)
+	sched_deps_info->finish_lhs ();
+
+      if (code == SET)
+	{
+	  can_start_lhs_rhs_p = cslr_p;
+
+	  sched_analyze_2 (deps, SET_SRC (x), insn);
+
+	  can_start_lhs_rhs_p = false;
+	}
+
+      return;
+    }
+
+  while (GET_CODE (dest) == STRICT_LOW_PART || GET_CODE (dest) == SUBREG
+	 || GET_CODE (dest) == ZERO_EXTRACT)
+    {
+      if (GET_CODE (dest) == STRICT_LOW_PART
+	 || GET_CODE (dest) == ZERO_EXTRACT
+	 || df_read_modify_subreg_p (dest))
+        {
+	  /* These both read and modify the result.  We must handle
+             them as writes to get proper dependencies for following
+             instructions.  We must handle them as reads to get proper
+             dependencies from this to previous instructions.
+             Thus we need to call sched_analyze_2.  */
+
+	  sched_analyze_2 (deps, XEXP (dest, 0), insn);
+	}
+      if (GET_CODE (dest) == ZERO_EXTRACT)
+	{
+	  /* The second and third arguments are values read by this insn.  */
+	  sched_analyze_2 (deps, XEXP (dest, 1), insn);
+	  sched_analyze_2 (deps, XEXP (dest, 2), insn);
+	}
+      dest = XEXP (dest, 0);
+    }
+
+  if (REG_P (dest))
+    {
+      int regno = REGNO (dest);
+      enum machine_mode mode = GET_MODE (dest);
+
+      sched_analyze_reg (deps, regno, mode, code, insn);
+
+#ifdef STACK_REGS
+      /* Treat all writes to a stack register as modifying the TOS.  */
+      if (regno >= FIRST_STACK_REG && regno <= LAST_STACK_REG)
+	{
+	  /* Avoid analyzing the same register twice.  */
+	  if (regno != FIRST_STACK_REG)
+	    sched_analyze_reg (deps, FIRST_STACK_REG, mode, code, insn);
+	  sched_analyze_reg (deps, FIRST_STACK_REG, mode, USE, insn);
+	}
+#endif
+    }
+  else if (MEM_P (dest))
+    {
+      /* Writing memory.  */
+      rtx t = dest;
+
+      if (sched_deps_info->use_cselib)
+	{
+	  t = shallow_copy_rtx (dest);
+	  cselib_lookup (XEXP (t, 0), Pmode, 1);
+	  XEXP (t, 0) = cselib_subst_to_values (XEXP (t, 0));
+	}
+      t = canon_rtx (t);
+
+      /* Pending lists can't get larger with a readonly context.  */
+      if (!deps->readonly
+          && ((deps->pending_read_list_length + deps->pending_write_list_length)
+              > MAX_PENDING_LIST_LENGTH))
+	{
+	  /* Flush all pending reads and writes to prevent the pending lists
+	     from getting any larger.  Insn scheduling runs too slowly when
+	     these lists get long.  When compiling GCC with itself,
+	     this flush occurs 8 times for sparc, and 10 times for m88k using
+	     the default value of 32.  */
+	  flush_pending_lists (deps, insn, false, true);
+	}
+      else
+	{
+	  rtx pending, pending_mem;
+
+	  pending = deps->pending_read_insns;
+	  pending_mem = deps->pending_read_mems;
+	  while (pending)
+	    {
+	      if (anti_dependence (XEXP (pending_mem, 0), t)
+		  && ! sched_insns_conditions_mutex_p (insn, XEXP (pending, 0)))
+		note_mem_dep (t, XEXP (pending_mem, 0), XEXP (pending, 0),
+			      DEP_ANTI);
+
+	      pending = XEXP (pending, 1);
+	      pending_mem = XEXP (pending_mem, 1);
+	    }
+
+	  pending = deps->pending_write_insns;
+	  pending_mem = deps->pending_write_mems;
+	  while (pending)
+	    {
+	      if (output_dependence (XEXP (pending_mem, 0), t)
+		  && ! sched_insns_conditions_mutex_p (insn, XEXP (pending, 0)))
+		note_mem_dep (t, XEXP (pending_mem, 0), XEXP (pending, 0),
+			      DEP_OUTPUT);
+
+	      pending = XEXP (pending, 1);
+	      pending_mem = XEXP (pending_mem, 1);
+	    }
+
+	  add_dependence_list (insn, deps->last_pending_memory_flush, 1,
+			       REG_DEP_ANTI);
+
+          if (!deps->readonly)
+            add_insn_mem_dependence (deps, false, insn, dest);
+	}
+      sched_analyze_2 (deps, XEXP (dest, 0), insn);
+    }
+
+  if (cslr_p && sched_deps_info->finish_lhs)
+    sched_deps_info->finish_lhs ();
+
+  /* Analyze reads.  */
+  if (GET_CODE (x) == SET)
+    {
+      can_start_lhs_rhs_p = cslr_p;
+
+      sched_analyze_2 (deps, SET_SRC (x), insn);
+
+      can_start_lhs_rhs_p = false;
+    }
+}
+
+/* Analyze the uses of memory and registers in rtx X in INSN.  */
+static void
+sched_analyze_2 (struct deps *deps, rtx x, rtx insn)
+{
+  int i;
+  int j;
+  enum rtx_code code;
+  const char *fmt;
+  bool cslr_p = can_start_lhs_rhs_p;
+
+  can_start_lhs_rhs_p = false;
+
+  gcc_assert (x);
+  if (x == 0)
+    return;
+
+  if (cslr_p && sched_deps_info->start_rhs)
+    sched_deps_info->start_rhs (x);
+
+  code = GET_CODE (x);
+
+  switch (code)
+    {
+    case CONST_INT:
+    case CONST_DOUBLE:
+    case CONST_FIXED:
+    case CONST_VECTOR:
+    case SYMBOL_REF:
+    case CONST:
+    case LABEL_REF:
+      /* Ignore constants.  */
+      if (cslr_p && sched_deps_info->finish_rhs)
+	sched_deps_info->finish_rhs ();
+
+      return;
+
+#ifdef HAVE_cc0
+    case CC0:
+      /* User of CC0 depends on immediately preceding insn.  */
+      SCHED_GROUP_P (insn) = 1;
+       /* Don't move CC0 setter to another block (it can set up the
+        same flag for previous CC0 users which is safe).  */
+      CANT_MOVE (prev_nonnote_insn (insn)) = 1;
+
+      if (cslr_p && sched_deps_info->finish_rhs)
+	sched_deps_info->finish_rhs ();
+
+      return;
+#endif
+
+    case REG:
+      {
+	int regno = REGNO (x);
+	enum machine_mode mode = GET_MODE (x);
+
+	sched_analyze_reg (deps, regno, mode, USE, insn);
+
+#ifdef STACK_REGS
+      /* Treat all reads of a stack register as modifying the TOS.  */
+      if (regno >= FIRST_STACK_REG && regno <= LAST_STACK_REG)
+	{
+	  /* Avoid analyzing the same register twice.  */
+	  if (regno != FIRST_STACK_REG)
+	    sched_analyze_reg (deps, FIRST_STACK_REG, mode, USE, insn);
+	  sched_analyze_reg (deps, FIRST_STACK_REG, mode, SET, insn);
+	}
+#endif
+
+	if (cslr_p && sched_deps_info->finish_rhs)
+	  sched_deps_info->finish_rhs ();
+
+	return;
+      }
+
+    case MEM:
+      {
+	/* Reading memory.  */
+	rtx u;
+	rtx pending, pending_mem;
+	rtx t = x;
+
+	if (sched_deps_info->use_cselib)
+	  {
+	    t = shallow_copy_rtx (t);
+	    cselib_lookup (XEXP (t, 0), Pmode, 1);
+	    XEXP (t, 0) = cselib_subst_to_values (XEXP (t, 0));
+	  }
+	t = canon_rtx (t);
+	pending = deps->pending_read_insns;
+	pending_mem = deps->pending_read_mems;
+	while (pending)
+	  {
+	    if (read_dependence (XEXP (pending_mem, 0), t)
+		&& ! sched_insns_conditions_mutex_p (insn, XEXP (pending, 0)))
+	      note_mem_dep (t, XEXP (pending_mem, 0), XEXP (pending, 0),
+			    DEP_ANTI);
+
+	    pending = XEXP (pending, 1);
+	    pending_mem = XEXP (pending_mem, 1);
+	  }
+
+	pending = deps->pending_write_insns;
+	pending_mem = deps->pending_write_mems;
+	while (pending)
+	  {
+	    if (true_dependence (XEXP (pending_mem, 0), VOIDmode,
+				 t, rtx_varies_p)
+		&& ! sched_insns_conditions_mutex_p (insn, XEXP (pending, 0)))
+	      note_mem_dep (t, XEXP (pending_mem, 0), XEXP (pending, 0),
+			    sched_deps_info->generate_spec_deps
+			    ? BEGIN_DATA | DEP_TRUE : DEP_TRUE);
+
+	    pending = XEXP (pending, 1);
+	    pending_mem = XEXP (pending_mem, 1);
+	  }
+
+	for (u = deps->last_pending_memory_flush; u; u = XEXP (u, 1))
+	  {
+	    if (! JUMP_P (XEXP (u, 0)))
+	      add_dependence (insn, XEXP (u, 0), REG_DEP_ANTI);
+	    else if (deps_may_trap_p (x))
+	      {
+		if ((sched_deps_info->generate_spec_deps)
+		    && sel_sched_p () && (spec_info->mask & BEGIN_CONTROL))
+		  {
+		    ds_t ds = set_dep_weak (DEP_ANTI, BEGIN_CONTROL,
+					    MAX_DEP_WEAK);
+
+		    note_dep (XEXP (u, 0), ds);
+		  }
+		else
+		  add_dependence (insn, XEXP (u, 0), REG_DEP_ANTI);
+	      }
+	  }
+
+	/* Always add these dependencies to pending_reads, since
+	   this insn may be followed by a write.  */
+        if (!deps->readonly)
+          add_insn_mem_dependence (deps, true, insn, x);
+
+	/* Take advantage of tail recursion here.  */
+	sched_analyze_2 (deps, XEXP (x, 0), insn);
+
+	if (cslr_p && sched_deps_info->finish_rhs)
+	  sched_deps_info->finish_rhs ();
+
+	return;
+      }
+
+    /* Force pending stores to memory in case a trap handler needs them.  */
+    case TRAP_IF:
+      flush_pending_lists (deps, insn, true, false);
+      break;
+
+    case UNSPEC_VOLATILE:
+      flush_pending_lists (deps, insn, true, true);
+      /* FALLTHRU */
+
+    case ASM_OPERANDS:
+    case ASM_INPUT:
+      {
+	/* Traditional and volatile asm instructions must be considered to use
+	   and clobber all hard registers, all pseudo-registers and all of
+	   memory.  So must TRAP_IF and UNSPEC_VOLATILE operations.
+
+	   Consider for instance a volatile asm that changes the fpu rounding
+	   mode.  An insn should not be moved across this even if it only uses
+	   pseudo-regs because it might give an incorrectly rounded result.  */
+	if (code != ASM_OPERANDS || MEM_VOLATILE_P (x))
+	  reg_pending_barrier = TRUE_BARRIER;
+
+	/* For all ASM_OPERANDS, we must traverse the vector of input operands.
+	   We can not just fall through here since then we would be confused
+	   by the ASM_INPUT rtx inside ASM_OPERANDS, which do not indicate
+	   traditional asms unlike their normal usage.  */
+
+	if (code == ASM_OPERANDS)
+	  {
+	    for (j = 0; j < ASM_OPERANDS_INPUT_LENGTH (x); j++)
+	      sched_analyze_2 (deps, ASM_OPERANDS_INPUT (x, j), insn);
+
+	    if (cslr_p && sched_deps_info->finish_rhs)
+	      sched_deps_info->finish_rhs ();
+
+	    return;
+	  }
+	break;
+      }
+
+    case PRE_DEC:
+    case POST_DEC:
+    case PRE_INC:
+    case POST_INC:
+      /* These both read and modify the result.  We must handle them as writes
+         to get proper dependencies for following instructions.  We must handle
+         them as reads to get proper dependencies from this to previous
+         instructions.  Thus we need to pass them to both sched_analyze_1
+         and sched_analyze_2.  We must call sched_analyze_2 first in order
+         to get the proper antecedent for the read.  */
+      sched_analyze_2 (deps, XEXP (x, 0), insn);
+      sched_analyze_1 (deps, x, insn);
+
+      if (cslr_p && sched_deps_info->finish_rhs)
+	sched_deps_info->finish_rhs ();
+
+      return;
+
+    case POST_MODIFY:
+    case PRE_MODIFY:
+      /* op0 = op0 + op1 */
+      sched_analyze_2 (deps, XEXP (x, 0), insn);
+      sched_analyze_2 (deps, XEXP (x, 1), insn);
+      sched_analyze_1 (deps, x, insn);
+
+      if (cslr_p && sched_deps_info->finish_rhs)
+	sched_deps_info->finish_rhs ();
+
+      return;
+
+    default:
+      break;
+    }
+
+  /* Other cases: walk the insn.  */
+  fmt = GET_RTX_FORMAT (code);
+  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
+    {
+      if (fmt[i] == 'e')
+	sched_analyze_2 (deps, XEXP (x, i), insn);
+      else if (fmt[i] == 'E')
+	for (j = 0; j < XVECLEN (x, i); j++)
+	  sched_analyze_2 (deps, XVECEXP (x, i, j), insn);
+    }
+
+  if (cslr_p && sched_deps_info->finish_rhs)
+    sched_deps_info->finish_rhs ();
+}
+
+/* Analyze an INSN with pattern X to find all dependencies.  */
+static void
+sched_analyze_insn (struct deps *deps, rtx x, rtx insn)
+{
+  RTX_CODE code = GET_CODE (x);
+  rtx link;
+  unsigned i;
+  reg_set_iterator rsi;
+
+  can_start_lhs_rhs_p = (NONJUMP_INSN_P (insn)
+			 && code == SET);
+
+  if (code == COND_EXEC)
+    {
+      sched_analyze_2 (deps, COND_EXEC_TEST (x), insn);
+
+      /* ??? Should be recording conditions so we reduce the number of
+	 false dependencies.  */
+      x = COND_EXEC_CODE (x);
+      code = GET_CODE (x);
+    }
+  if (code == SET || code == CLOBBER)
+    {
+      sched_analyze_1 (deps, x, insn);
+
+      /* Bare clobber insns are used for letting life analysis, reg-stack
+	 and others know that a value is dead.  Depend on the last call
+	 instruction so that reg-stack won't get confused.  */
+      if (code == CLOBBER)
+	add_dependence_list (insn, deps->last_function_call, 1, REG_DEP_OUTPUT);
+    }
+  else if (code == PARALLEL)
+    {
+      for (i = XVECLEN (x, 0); i--;)
+	{
+	  rtx sub = XVECEXP (x, 0, i);
+	  code = GET_CODE (sub);
+
+	  if (code == COND_EXEC)
+	    {
+	      sched_analyze_2 (deps, COND_EXEC_TEST (sub), insn);
+	      sub = COND_EXEC_CODE (sub);
+	      code = GET_CODE (sub);
+	    }
+	  if (code == SET || code == CLOBBER)
+	    sched_analyze_1 (deps, sub, insn);
+	  else
+	    sched_analyze_2 (deps, sub, insn);
+	}
+    }
+  else
+    sched_analyze_2 (deps, x, insn);
+
+  /* Mark registers CLOBBERED or used by called function.  */
+  if (CALL_P (insn))
+    {
+      for (link = CALL_INSN_FUNCTION_USAGE (insn); link; link = XEXP (link, 1))
+	{
+	  if (GET_CODE (XEXP (link, 0)) == CLOBBER)
+	    sched_analyze_1 (deps, XEXP (link, 0), insn);
+	  else
+	    sched_analyze_2 (deps, XEXP (link, 0), insn);
+	}
+      if (find_reg_note (insn, REG_SETJMP, NULL))
+	reg_pending_barrier = MOVE_BARRIER;
+    }
+
+  if (JUMP_P (insn))
+    {
+      rtx next;
+      next = next_nonnote_insn (insn);
+      if (next && BARRIER_P (next))
+	reg_pending_barrier = MOVE_BARRIER;
+      else
+	{
+	  rtx pending, pending_mem;
+
+          if (sched_deps_info->compute_jump_reg_dependencies)
+            {
+              regset_head tmp_uses, tmp_sets;
+              INIT_REG_SET (&tmp_uses);
+              INIT_REG_SET (&tmp_sets);
+
+              (*sched_deps_info->compute_jump_reg_dependencies)
+                (insn, &deps->reg_conditional_sets, &tmp_uses, &tmp_sets);
+              /* Make latency of jump equal to 0 by using anti-dependence.  */
+              EXECUTE_IF_SET_IN_REG_SET (&tmp_uses, 0, i, rsi)
+                {
+                  struct deps_reg *reg_last = &deps->reg_last[i];
+                  add_dependence_list (insn, reg_last->sets, 0, REG_DEP_ANTI);
+                  add_dependence_list (insn, reg_last->clobbers, 0,
+				       REG_DEP_ANTI);
+
+                  if (!deps->readonly)
+                    {
+                      reg_last->uses_length++;
+                      reg_last->uses = alloc_INSN_LIST (insn, reg_last->uses);
+                    }
+                }
+              IOR_REG_SET (reg_pending_sets, &tmp_sets);
+
+              CLEAR_REG_SET (&tmp_uses);
+              CLEAR_REG_SET (&tmp_sets);
+            }
+
+	  /* All memory writes and volatile reads must happen before the
+	     jump.  Non-volatile reads must happen before the jump iff
+	     the result is needed by the above register used mask.  */
+
+	  pending = deps->pending_write_insns;
+	  pending_mem = deps->pending_write_mems;
+	  while (pending)
+	    {
+	      if (! sched_insns_conditions_mutex_p (insn, XEXP (pending, 0)))
+		add_dependence (insn, XEXP (pending, 0), REG_DEP_OUTPUT);
+	      pending = XEXP (pending, 1);
+	      pending_mem = XEXP (pending_mem, 1);
+	    }
+
+	  pending = deps->pending_read_insns;
+	  pending_mem = deps->pending_read_mems;
+	  while (pending)
+	    {
+	      if (MEM_VOLATILE_P (XEXP (pending_mem, 0))
+		  && ! sched_insns_conditions_mutex_p (insn, XEXP (pending, 0)))
+		add_dependence (insn, XEXP (pending, 0), REG_DEP_OUTPUT);
+	      pending = XEXP (pending, 1);
+	      pending_mem = XEXP (pending_mem, 1);
+	    }
+
+	  add_dependence_list (insn, deps->last_pending_memory_flush, 1,
+			       REG_DEP_ANTI);
+	}
+    }
+
+  /* If this instruction can throw an exception, then moving it changes
+     where block boundaries fall.  This is mighty confusing elsewhere.
+     Therefore, prevent such an instruction from being moved.  Same for
+     non-jump instructions that define block boundaries.
+     ??? Unclear whether this is still necessary in EBB mode.  If not,
+     add_branch_dependences should be adjusted for RGN mode instead.  */
+  if (((CALL_P (insn) || JUMP_P (insn)) && can_throw_internal (insn))
+      || (NONJUMP_INSN_P (insn) && control_flow_insn_p (insn)))
+    reg_pending_barrier = MOVE_BARRIER;
+
+  /* If the current insn is conditional, we can't free any
+     of the lists.  */
+  if (sched_has_condition_p (insn))
+    {
+      EXECUTE_IF_SET_IN_REG_SET (reg_pending_uses, 0, i, rsi)
+        {
+          struct deps_reg *reg_last = &deps->reg_last[i];
+          add_dependence_list (insn, reg_last->sets, 0, REG_DEP_TRUE);
+          add_dependence_list (insn, reg_last->clobbers, 0, REG_DEP_TRUE);
+              
+          if (!deps->readonly)
+            {
+              reg_last->uses = alloc_INSN_LIST (insn, reg_last->uses);
+              reg_last->uses_length++;
+            }
+        }
+      EXECUTE_IF_SET_IN_REG_SET (reg_pending_clobbers, 0, i, rsi)
+        {
+          struct deps_reg *reg_last = &deps->reg_last[i];
+          add_dependence_list (insn, reg_last->sets, 0, REG_DEP_OUTPUT);
+          add_dependence_list (insn, reg_last->uses, 0, REG_DEP_ANTI);
+
+          if (!deps->readonly)
+            {
+              reg_last->clobbers = alloc_INSN_LIST (insn, reg_last->clobbers);
+              reg_last->clobbers_length++;
+            }
+        }
+      EXECUTE_IF_SET_IN_REG_SET (reg_pending_sets, 0, i, rsi)
+        {
+          struct deps_reg *reg_last = &deps->reg_last[i];
+          add_dependence_list (insn, reg_last->sets, 0, REG_DEP_OUTPUT);
+          add_dependence_list (insn, reg_last->clobbers, 0, REG_DEP_OUTPUT);
+          add_dependence_list (insn, reg_last->uses, 0, REG_DEP_ANTI);
+
+          if (!deps->readonly)
+            {
+              reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
+              SET_REGNO_REG_SET (&deps->reg_conditional_sets, i);
+            }
+        }
+    }
+  else
+    {
+      EXECUTE_IF_SET_IN_REG_SET (reg_pending_uses, 0, i, rsi)
+        {
+          struct deps_reg *reg_last = &deps->reg_last[i];
+          add_dependence_list (insn, reg_last->sets, 0, REG_DEP_TRUE);
+          add_dependence_list (insn, reg_last->clobbers, 0, REG_DEP_TRUE);
+
+          if (!deps->readonly)
+            {
+              reg_last->uses_length++;
+              reg_last->uses = alloc_INSN_LIST (insn, reg_last->uses);
+            }
+        }
+      EXECUTE_IF_SET_IN_REG_SET (reg_pending_clobbers, 0, i, rsi)
+        {
+          struct deps_reg *reg_last = &deps->reg_last[i];
+          if (reg_last->uses_length > MAX_PENDING_LIST_LENGTH
+              || reg_last->clobbers_length > MAX_PENDING_LIST_LENGTH)
+            {
+              add_dependence_list_and_free (deps, insn, &reg_last->sets, 0,
+                                            REG_DEP_OUTPUT);
+              add_dependence_list_and_free (deps, insn, &reg_last->uses, 0,
+                                            REG_DEP_ANTI);
+              add_dependence_list_and_free (deps, insn, &reg_last->clobbers, 0,
+                                            REG_DEP_OUTPUT);
+
+              if (!deps->readonly)
+                {
+                  reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
+                  reg_last->clobbers_length = 0;
+                  reg_last->uses_length = 0;
+                }
+            }
+          else
+            {
+              add_dependence_list (insn, reg_last->sets, 0, REG_DEP_OUTPUT);
+              add_dependence_list (insn, reg_last->uses, 0, REG_DEP_ANTI);
+            }
+
+          if (!deps->readonly)
+            {
+              reg_last->clobbers_length++;
+              reg_last->clobbers = alloc_INSN_LIST (insn, reg_last->clobbers);
+            }
+        }
+      EXECUTE_IF_SET_IN_REG_SET (reg_pending_sets, 0, i, rsi)
+        {
+          struct deps_reg *reg_last = &deps->reg_last[i];
+          add_dependence_list_and_free (deps, insn, &reg_last->sets, 0,
+                                        REG_DEP_OUTPUT);
+          add_dependence_list_and_free (deps, insn, &reg_last->clobbers, 0,
+                                        REG_DEP_OUTPUT);
+          add_dependence_list_and_free (deps, insn, &reg_last->uses, 0,
+                                        REG_DEP_ANTI);
+
+          if (!deps->readonly)
+            {
+              reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
+              reg_last->uses_length = 0;
+              reg_last->clobbers_length = 0;
+              CLEAR_REGNO_REG_SET (&deps->reg_conditional_sets, i);
+            }
+        }
+    }
+
+  if (!deps->readonly)
+    {
+      IOR_REG_SET (&deps->reg_last_in_use, reg_pending_uses);
+      IOR_REG_SET (&deps->reg_last_in_use, reg_pending_clobbers);
+      IOR_REG_SET (&deps->reg_last_in_use, reg_pending_sets);
+
+      /* Set up the pending barrier found.  */
+      deps->last_reg_pending_barrier = reg_pending_barrier;
+    }
+
+  CLEAR_REG_SET (reg_pending_uses);
+  CLEAR_REG_SET (reg_pending_clobbers);
+  CLEAR_REG_SET (reg_pending_sets);
+
+  /* Add dependencies if a scheduling barrier was found.  */
+  if (reg_pending_barrier)
+    {
+      /* In the case of barrier the most added dependencies are not
+         real, so we use anti-dependence here.  */
+      if (sched_has_condition_p (insn))
+	{
+	  EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i, rsi)
+	    {
+	      struct deps_reg *reg_last = &deps->reg_last[i];
+	      add_dependence_list (insn, reg_last->uses, 0, REG_DEP_ANTI);
+	      add_dependence_list
+		(insn, reg_last->sets, 0,
+		 reg_pending_barrier == TRUE_BARRIER ? REG_DEP_TRUE : REG_DEP_ANTI);
+	      add_dependence_list
+		(insn, reg_last->clobbers, 0,
+		 reg_pending_barrier == TRUE_BARRIER ? REG_DEP_TRUE : REG_DEP_ANTI);
+	    }
+	}
+      else
+	{
+	  EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i, rsi)
+	    {
+	      struct deps_reg *reg_last = &deps->reg_last[i];
+	      add_dependence_list_and_free (deps, insn, &reg_last->uses, 0,
+					    REG_DEP_ANTI);
+	      add_dependence_list_and_free
+		(deps, insn, &reg_last->sets, 0,
+		 reg_pending_barrier == TRUE_BARRIER ? REG_DEP_TRUE : REG_DEP_ANTI);
+	      add_dependence_list_and_free
+		(deps, insn, &reg_last->clobbers, 0,
+		 reg_pending_barrier == TRUE_BARRIER ? REG_DEP_TRUE : REG_DEP_ANTI);
+
+              if (!deps->readonly)
+                {
+                  reg_last->uses_length = 0;
+                  reg_last->clobbers_length = 0;
+                }
+	    }
+	}
+
+      if (!deps->readonly)
+        for (i = 0; i < (unsigned)deps->max_reg; i++)
+          {
+            struct deps_reg *reg_last = &deps->reg_last[i];
+            reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
+            SET_REGNO_REG_SET (&deps->reg_last_in_use, i);
+          }
+
+      /* Flush pending lists on jumps, but not on speculative checks.  */
+      if (JUMP_P (insn) && !(sel_sched_p () 
+                             && sel_insn_is_speculation_check (insn)))
+	flush_pending_lists (deps, insn, true, true);
+      
+      if (!deps->readonly)
+        CLEAR_REG_SET (&deps->reg_conditional_sets);
+      reg_pending_barrier = NOT_A_BARRIER;
+    }
+
+  /* If a post-call group is still open, see if it should remain so.
+     This insn must be a simple move of a hard reg to a pseudo or
+     vice-versa.
+
+     We must avoid moving these insns for correctness on
+     SMALL_REGISTER_CLASS machines, and for special registers like
+     PIC_OFFSET_TABLE_REGNUM.  For simplicity, extend this to all
+     hard regs for all targets.  */
+
+  if (deps->in_post_call_group_p)
+    {
+      rtx tmp, set = single_set (insn);
+      int src_regno, dest_regno;
+
+      if (set == NULL)
+	goto end_call_group;
+
+      tmp = SET_DEST (set);
+      if (GET_CODE (tmp) == SUBREG)
+	tmp = SUBREG_REG (tmp);
+      if (REG_P (tmp))
+	dest_regno = REGNO (tmp);
+      else
+	goto end_call_group;
+
+      tmp = SET_SRC (set);
+      if (GET_CODE (tmp) == SUBREG)
+	tmp = SUBREG_REG (tmp);
+      if ((GET_CODE (tmp) == PLUS
+	   || GET_CODE (tmp) == MINUS)
+	  && REG_P (XEXP (tmp, 0))
+	  && REGNO (XEXP (tmp, 0)) == STACK_POINTER_REGNUM
+	  && dest_regno == STACK_POINTER_REGNUM)
+	src_regno = STACK_POINTER_REGNUM;
+      else if (REG_P (tmp))
+	src_regno = REGNO (tmp);
+      else
+	goto end_call_group;
+
+      if (src_regno < FIRST_PSEUDO_REGISTER
+	  || dest_regno < FIRST_PSEUDO_REGISTER)
+	{
+	  if (!deps->readonly
+              && deps->in_post_call_group_p == post_call_initial)
+	    deps->in_post_call_group_p = post_call;
+
+          if (!sel_sched_p () || sched_emulate_haifa_p) 
+            {
+              SCHED_GROUP_P (insn) = 1;
+              CANT_MOVE (insn) = 1;
+            }
+	}
+      else
+	{
+	end_call_group:
+          if (!deps->readonly)
+            deps->in_post_call_group_p = not_post_call;
+	}
+    }
+
+  if ((current_sched_info->flags & DO_SPECULATION)
+      && !sched_insn_is_legitimate_for_speculation_p (insn, 0))
+    /* INSN has an internal dependency (e.g. r14 = [r14]) and thus cannot
+       be speculated.  */
+    {
+      if (sel_sched_p ())
+        sel_mark_hard_insn (insn);
+      else
+        {
+          sd_iterator_def sd_it;
+          dep_t dep;
+          
+          for (sd_it = sd_iterator_start (insn, SD_LIST_SPEC_BACK);
+               sd_iterator_cond (&sd_it, &dep);)
+            change_spec_dep_to_hard (sd_it);
+        }
+    }
+}
+
+/* Analyze INSN with DEPS as a context.  */
+void
+deps_analyze_insn (struct deps *deps, rtx insn)
+{
+  if (sched_deps_info->start_insn)
+    sched_deps_info->start_insn (insn);
+
+  if (NONJUMP_INSN_P (insn) || JUMP_P (insn))
+    {
+      /* Make each JUMP_INSN (but not a speculative check) 
+         a scheduling barrier for memory references.  */
+      if (!deps->readonly
+          && JUMP_P (insn) 
+          && !(sel_sched_p () 
+               && sel_insn_is_speculation_check (insn)))
+        {
+          /* Keep the list a reasonable size.  */
+          if (deps->pending_flush_length++ > MAX_PENDING_LIST_LENGTH)
+            flush_pending_lists (deps, insn, true, true);
+          else
+            deps->last_pending_memory_flush
+              = alloc_INSN_LIST (insn, deps->last_pending_memory_flush);
+        }
+
+      sched_analyze_insn (deps, PATTERN (insn), insn);
+    }
+  else if (CALL_P (insn))
+    {
+      int i;
+
+      CANT_MOVE (insn) = 1;
+
+      if (find_reg_note (insn, REG_SETJMP, NULL))
+        {
+          /* This is setjmp.  Assume that all registers, not just
+             hard registers, may be clobbered by this call.  */
+          reg_pending_barrier = MOVE_BARRIER;
+        }
+      else
+        {
+          for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+            /* A call may read and modify global register variables.  */
+            if (global_regs[i])
+              {
+                SET_REGNO_REG_SET (reg_pending_sets, i);
+                SET_REGNO_REG_SET (reg_pending_uses, i);
+              }
+          /* Other call-clobbered hard regs may be clobbered.
+             Since we only have a choice between 'might be clobbered'
+             and 'definitely not clobbered', we must include all
+             partly call-clobbered registers here.  */
+            else if (HARD_REGNO_CALL_PART_CLOBBERED (i, reg_raw_mode[i])
+                     || TEST_HARD_REG_BIT (regs_invalidated_by_call, i))
+              SET_REGNO_REG_SET (reg_pending_clobbers, i);
+          /* We don't know what set of fixed registers might be used
+             by the function, but it is certain that the stack pointer
+             is among them, but be conservative.  */
+            else if (fixed_regs[i])
+              SET_REGNO_REG_SET (reg_pending_uses, i);
+          /* The frame pointer is normally not used by the function
+             itself, but by the debugger.  */
+          /* ??? MIPS o32 is an exception.  It uses the frame pointer
+             in the macro expansion of jal but does not represent this
+             fact in the call_insn rtl.  */
+            else if (i == FRAME_POINTER_REGNUM
+                     || (i == HARD_FRAME_POINTER_REGNUM
+                         && (! reload_completed || frame_pointer_needed)))
+              SET_REGNO_REG_SET (reg_pending_uses, i);
+        }
+
+      /* For each insn which shouldn't cross a call, add a dependence
+         between that insn and this call insn.  */
+      add_dependence_list_and_free (deps, insn, 
+                                    &deps->sched_before_next_call, 1,
+                                    REG_DEP_ANTI);
+
+      sched_analyze_insn (deps, PATTERN (insn), insn);
+
+      /* If CALL would be in a sched group, then this will violate
+	 convention that sched group insns have dependencies only on the
+	 previous instruction.
+
+	 Of course one can say: "Hey!  What about head of the sched group?"
+	 And I will answer: "Basic principles (one dep per insn) are always
+	 the same."  */
+      gcc_assert (!SCHED_GROUP_P (insn));
+
+      /* In the absence of interprocedural alias analysis, we must flush
+         all pending reads and writes, and start new dependencies starting
+         from here.  But only flush writes for constant calls (which may
+         be passed a pointer to something we haven't written yet).  */
+      flush_pending_lists (deps, insn, true, ! RTL_CONST_OR_PURE_CALL_P (insn));
+
+      if (!deps->readonly)
+        {
+          /* Remember the last function call for limiting lifetimes.  */
+          free_INSN_LIST_list (&deps->last_function_call);
+          deps->last_function_call = alloc_INSN_LIST (insn, NULL_RTX);
+          
+          /* Before reload, begin a post-call group, so as to keep the
+             lifetimes of hard registers correct.  */
+          if (! reload_completed)
+            deps->in_post_call_group_p = post_call;
+        }
+    }
+
+  if (sched_deps_info->use_cselib)
+    cselib_process_insn (insn);
+
+  /* EH_REGION insn notes can not appear until well after we complete
+     scheduling.  */
+  if (NOTE_P (insn))
+    gcc_assert (NOTE_KIND (insn) != NOTE_INSN_EH_REGION_BEG
+		&& NOTE_KIND (insn) != NOTE_INSN_EH_REGION_END);
+
+  if (sched_deps_info->finish_insn)
+    sched_deps_info->finish_insn ();
+
+  /* Fixup the dependencies in the sched group.  */
+  if ((NONJUMP_INSN_P (insn) || JUMP_P (insn)) 
+      && SCHED_GROUP_P (insn) && !sel_sched_p ())
+    fixup_sched_groups (insn);
+}
+
+/* Initialize DEPS for the new block beginning with HEAD.  */
+void
+deps_start_bb (struct deps *deps, rtx head)
+{
+  gcc_assert (!deps->readonly);
+
+  /* Before reload, if the previous block ended in a call, show that
+     we are inside a post-call group, so as to keep the lifetimes of
+     hard registers correct.  */
+  if (! reload_completed && !LABEL_P (head))
+    {
+      rtx insn = prev_nonnote_insn (head);
+
+      if (insn && CALL_P (insn))
+	deps->in_post_call_group_p = post_call_initial;
+    }
+}
+
+/* Analyze every insn between HEAD and TAIL inclusive, creating backward
+   dependencies for each insn.  */
+void
+sched_analyze (struct deps *deps, rtx head, rtx tail)
+{
+  rtx insn;
+
+  if (sched_deps_info->use_cselib)
+    cselib_init (true);
+
+  deps_start_bb (deps, head);
+
+  for (insn = head;; insn = NEXT_INSN (insn))
+    {
+
+      if (INSN_P (insn))
+	{
+	  /* And initialize deps_lists.  */
+	  sd_init_insn (insn);
+	}
+
+      deps_analyze_insn (deps, insn);
+
+      if (insn == tail)
+	{
+	  if (sched_deps_info->use_cselib)
+	    cselib_finish ();
+	  return;
+	}
+    }
+  gcc_unreachable ();
+}
+
+/* Helper for sched_free_deps ().
+   Delete INSN's (RESOLVED_P) backward dependencies.  */
+static void
+delete_dep_nodes_in_back_deps (rtx insn, bool resolved_p)
+{
+  sd_iterator_def sd_it;
+  dep_t dep;
+  sd_list_types_def types;
+
+  if (resolved_p)
+    types = SD_LIST_RES_BACK;
+  else
+    types = SD_LIST_BACK;
+
+  for (sd_it = sd_iterator_start (insn, types);
+       sd_iterator_cond (&sd_it, &dep);)
+    {
+      dep_link_t link = *sd_it.linkp;
+      dep_node_t node = DEP_LINK_NODE (link);
+      deps_list_t back_list;
+      deps_list_t forw_list;
+
+      get_back_and_forw_lists (dep, resolved_p, &back_list, &forw_list);
+      remove_from_deps_list (link, back_list);
+      delete_dep_node (node);
+    }
+}
+
+/* Delete (RESOLVED_P) dependencies between HEAD and TAIL together with
+   deps_lists.  */
+void
+sched_free_deps (rtx head, rtx tail, bool resolved_p)
+{
+  rtx insn;
+  rtx next_tail = NEXT_INSN (tail);
+
+  for (insn = head; insn != next_tail; insn = NEXT_INSN (insn))
+    if (INSN_P (insn) && INSN_LUID (insn) > 0)
+      {
+	/* Clear resolved back deps together with its dep_nodes.  */
+	delete_dep_nodes_in_back_deps (insn, resolved_p);
+
+	/* Clear forward deps and leave the dep_nodes to the
+	   corresponding back_deps list.  */
+	if (resolved_p)
+	  clear_deps_list (INSN_RESOLVED_FORW_DEPS (insn));
+	else
+	  clear_deps_list (INSN_FORW_DEPS (insn));
+
+	sd_finish_insn (insn);
+      }
+}
+
+/* Initialize variables for region data dependence analysis.
+   n_bbs is the number of region blocks.  */
+
+void
+init_deps (struct deps *deps)
+{
+  int max_reg = (reload_completed ? FIRST_PSEUDO_REGISTER : max_reg_num ());
+
+  deps->max_reg = max_reg;
+  deps->reg_last = XCNEWVEC (struct deps_reg, max_reg);
+  INIT_REG_SET (&deps->reg_last_in_use);
+  INIT_REG_SET (&deps->reg_conditional_sets);
+
+  deps->pending_read_insns = 0;
+  deps->pending_read_mems = 0;
+  deps->pending_write_insns = 0;
+  deps->pending_write_mems = 0;
+  deps->pending_read_list_length = 0;
+  deps->pending_write_list_length = 0;
+  deps->pending_flush_length = 0;
+  deps->last_pending_memory_flush = 0;
+  deps->last_function_call = 0;
+  deps->sched_before_next_call = 0;
+  deps->in_post_call_group_p = not_post_call;
+  deps->last_reg_pending_barrier = NOT_A_BARRIER;
+  deps->readonly = 0;
+}
+
+/* Free insn lists found in DEPS.  */
+
+void
+free_deps (struct deps *deps)
+{
+  unsigned i;
+  reg_set_iterator rsi;
+
+  free_INSN_LIST_list (&deps->pending_read_insns);
+  free_EXPR_LIST_list (&deps->pending_read_mems);
+  free_INSN_LIST_list (&deps->pending_write_insns);
+  free_EXPR_LIST_list (&deps->pending_write_mems);
+  free_INSN_LIST_list (&deps->last_pending_memory_flush);
+
+  /* Without the EXECUTE_IF_SET, this loop is executed max_reg * nr_regions
+     times.  For a testcase with 42000 regs and 8000 small basic blocks,
+     this loop accounted for nearly 60% (84 sec) of the total -O2 runtime.  */
+  EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i, rsi)
+    {
+      struct deps_reg *reg_last = &deps->reg_last[i];
+      if (reg_last->uses)
+	free_INSN_LIST_list (&reg_last->uses);
+      if (reg_last->sets)
+	free_INSN_LIST_list (&reg_last->sets);
+      if (reg_last->clobbers)
+	free_INSN_LIST_list (&reg_last->clobbers);
+    }
+  CLEAR_REG_SET (&deps->reg_last_in_use);
+  CLEAR_REG_SET (&deps->reg_conditional_sets);
+
+  free (deps->reg_last);
+  deps->reg_last = NULL;
+
+  deps = NULL;
+}
+
+/* Remove INSN from dependence contexts DEPS.  Caution: reg_conditional_sets
+   is not handled.  */
+void
+remove_from_deps (struct deps *deps, rtx insn)
+{
+  int removed;
+  unsigned i;
+  reg_set_iterator rsi;
+  
+  removed = remove_from_both_dependence_lists (insn, &deps->pending_read_insns,
+                                               &deps->pending_read_mems);
+  deps->pending_read_list_length -= removed;
+  removed = remove_from_both_dependence_lists (insn, &deps->pending_write_insns,
+                                               &deps->pending_write_mems);
+  deps->pending_write_list_length -= removed;
+  removed = remove_from_dependence_list (insn, &deps->last_pending_memory_flush);
+  deps->pending_flush_length -= removed;
+
+  EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i, rsi)
+    {
+      struct deps_reg *reg_last = &deps->reg_last[i];
+      if (reg_last->uses)
+	remove_from_dependence_list (insn, &reg_last->uses);
+      if (reg_last->sets)
+	remove_from_dependence_list (insn, &reg_last->sets);
+      if (reg_last->clobbers)
+	remove_from_dependence_list (insn, &reg_last->clobbers);
+      if (!reg_last->uses && !reg_last->sets && !reg_last->clobbers)
+        CLEAR_REGNO_REG_SET (&deps->reg_last_in_use, i);
+    }
+
+  if (CALL_P (insn))
+    remove_from_dependence_list (insn, &deps->last_function_call);
+  remove_from_dependence_list (insn, &deps->sched_before_next_call);
+}
+
+/* Init deps data vector.  */
+static void
+init_deps_data_vector (void)
+{
+  int reserve = (sched_max_luid + 1 
+                 - VEC_length (haifa_deps_insn_data_def, h_d_i_d));
+  if (reserve > 0 
+      && ! VEC_space (haifa_deps_insn_data_def, h_d_i_d, reserve))
+    VEC_safe_grow_cleared (haifa_deps_insn_data_def, heap, h_d_i_d,
+                           3 * sched_max_luid / 2);
+}
+
+/* If it is profitable to use them, initialize or extend (depending on
+   GLOBAL_P) dependency data.  */
+void
+sched_deps_init (bool global_p)
+{
+  /* Average number of insns in the basic block.
+     '+ 1' is used to make it nonzero.  */
+  int insns_in_block = sched_max_luid / n_basic_blocks + 1;
+
+  init_deps_data_vector ();
+  
+  /* We use another caching mechanism for selective scheduling, so 
+     we don't use this one.  */
+  if (!sel_sched_p () && global_p && insns_in_block > 100 * 5)
+    {
+      /* ?!? We could save some memory by computing a per-region luid mapping
+         which could reduce both the number of vectors in the cache and the
+         size of each vector.  Instead we just avoid the cache entirely unless
+         the average number of instructions in a basic block is very high.  See
+         the comment before the declaration of true_dependency_cache for
+         what we consider "very high".  */
+      cache_size = 0;
+      extend_dependency_caches (sched_max_luid, true);
+    }
+
+  if (global_p) 
+    {
+      dl_pool = create_alloc_pool ("deps_list", sizeof (struct _deps_list),
+                                   /* Allocate lists for one block at a time.  */
+                                   insns_in_block);
+      dn_pool = create_alloc_pool ("dep_node", sizeof (struct _dep_node),
+                                   /* Allocate nodes for one block at a time.
+                                      We assume that average insn has
+                                      5 producers.  */
+                                   5 * insns_in_block);
+    }
+}
+
+
+/* Create or extend (depending on CREATE_P) dependency caches to
+   size N.  */
+void
+extend_dependency_caches (int n, bool create_p)
+{
+  if (create_p || true_dependency_cache)
+    {
+      int i, luid = cache_size + n;
+
+      true_dependency_cache = XRESIZEVEC (bitmap_head, true_dependency_cache,
+					  luid);
+      output_dependency_cache = XRESIZEVEC (bitmap_head,
+					    output_dependency_cache, luid);
+      anti_dependency_cache = XRESIZEVEC (bitmap_head, anti_dependency_cache,
+					  luid);
+
+      if (current_sched_info->flags & DO_SPECULATION)
+        spec_dependency_cache = XRESIZEVEC (bitmap_head, spec_dependency_cache,
+					    luid);
+
+      for (i = cache_size; i < luid; i++)
+	{
+	  bitmap_initialize (&true_dependency_cache[i], 0);
+	  bitmap_initialize (&output_dependency_cache[i], 0);
+	  bitmap_initialize (&anti_dependency_cache[i], 0);
+
+          if (current_sched_info->flags & DO_SPECULATION)
+            bitmap_initialize (&spec_dependency_cache[i], 0);
+	}
+      cache_size = luid;
+    }
+}
+
+/* Finalize dependency information for the whole function.  */
+void
+sched_deps_finish (void)
+{
+  gcc_assert (deps_pools_are_empty_p ());
+  free_alloc_pool_if_empty (&dn_pool);
+  free_alloc_pool_if_empty (&dl_pool);
+  gcc_assert (dn_pool == NULL && dl_pool == NULL);
+
+  VEC_free (haifa_deps_insn_data_def, heap, h_d_i_d);
+  cache_size = 0;
+  
+  if (true_dependency_cache)
+    {
+      int i;
+
+      for (i = 0; i < cache_size; i++)
+	{
+	  bitmap_clear (&true_dependency_cache[i]);
+	  bitmap_clear (&output_dependency_cache[i]);
+	  bitmap_clear (&anti_dependency_cache[i]);
+
+          if (sched_deps_info->generate_spec_deps)
+            bitmap_clear (&spec_dependency_cache[i]);
+	}
+      free (true_dependency_cache);
+      true_dependency_cache = NULL;
+      free (output_dependency_cache);
+      output_dependency_cache = NULL;
+      free (anti_dependency_cache);
+      anti_dependency_cache = NULL;
+
+      if (sched_deps_info->generate_spec_deps)
+        {
+          free (spec_dependency_cache);
+          spec_dependency_cache = NULL;
+        }
+
+    }
+}
+
+/* Initialize some global variables needed by the dependency analysis
+   code.  */
+
+void
+init_deps_global (void)
+{
+  reg_pending_sets = ALLOC_REG_SET (&reg_obstack);
+  reg_pending_clobbers = ALLOC_REG_SET (&reg_obstack);
+  reg_pending_uses = ALLOC_REG_SET (&reg_obstack);
+  reg_pending_barrier = NOT_A_BARRIER;
+
+  if (!sel_sched_p () || sched_emulate_haifa_p)
+    {
+      sched_deps_info->start_insn = haifa_start_insn;
+      sched_deps_info->finish_insn = haifa_finish_insn;
+
+      sched_deps_info->note_reg_set = haifa_note_reg_set;
+      sched_deps_info->note_reg_clobber = haifa_note_reg_clobber;
+      sched_deps_info->note_reg_use = haifa_note_reg_use;
+
+      sched_deps_info->note_mem_dep = haifa_note_mem_dep;
+      sched_deps_info->note_dep = haifa_note_dep;
+   }
+}
+
+/* Free everything used by the dependency analysis code.  */
+
+void
+finish_deps_global (void)
+{
+  FREE_REG_SET (reg_pending_sets);
+  FREE_REG_SET (reg_pending_clobbers);
+  FREE_REG_SET (reg_pending_uses);
+}
+
+/* Estimate the weakness of dependence between MEM1 and MEM2.  */
+dw_t
+estimate_dep_weak (rtx mem1, rtx mem2)
+{
+  rtx r1, r2;
+
+  if (mem1 == mem2)
+    /* MEMs are the same - don't speculate.  */
+    return MIN_DEP_WEAK;
+
+  r1 = XEXP (mem1, 0);
+  r2 = XEXP (mem2, 0);
+
+  if (r1 == r2
+      || (REG_P (r1) && REG_P (r2)
+	  && REGNO (r1) == REGNO (r2)))
+    /* Again, MEMs are the same.  */
+    return MIN_DEP_WEAK;
+  else if ((REG_P (r1) && !REG_P (r2))
+	   || (!REG_P (r1) && REG_P (r2)))
+    /* Different addressing modes - reason to be more speculative,
+       than usual.  */
+    return NO_DEP_WEAK - (NO_DEP_WEAK - UNCERTAIN_DEP_WEAK) / 2;
+  else
+    /* We can't say anything about the dependence.  */
+    return UNCERTAIN_DEP_WEAK;
+}
+
+/* Add or update backward dependence between INSN and ELEM with type DEP_TYPE.
+   This function can handle same INSN and ELEM (INSN == ELEM).
+   It is a convenience wrapper.  */
+void
+add_dependence (rtx insn, rtx elem, enum reg_note dep_type)
+{
+  ds_t ds;
+  bool internal;
+
+  if (dep_type == REG_DEP_TRUE)
+    ds = DEP_TRUE;
+  else if (dep_type == REG_DEP_OUTPUT)
+    ds = DEP_OUTPUT;
+  else
+    {
+      gcc_assert (dep_type == REG_DEP_ANTI);
+      ds = DEP_ANTI;
+    }
+
+  /* When add_dependence is called from inside sched-deps.c, we expect
+     cur_insn to be non-null.  */
+  internal = cur_insn != NULL;
+  if (internal)
+    gcc_assert (insn == cur_insn);
+  else
+    cur_insn = insn;
+      
+  note_dep (elem, ds);
+  if (!internal)
+    cur_insn = NULL;
+}
+
+/* Return weakness of speculative type TYPE in the dep_status DS.  */
+dw_t
+get_dep_weak_1 (ds_t ds, ds_t type)
+{
+  ds = ds & type;
+
+  switch (type)
+    {
+    case BEGIN_DATA: ds >>= BEGIN_DATA_BITS_OFFSET; break;
+    case BE_IN_DATA: ds >>= BE_IN_DATA_BITS_OFFSET; break;
+    case BEGIN_CONTROL: ds >>= BEGIN_CONTROL_BITS_OFFSET; break;
+    case BE_IN_CONTROL: ds >>= BE_IN_CONTROL_BITS_OFFSET; break;
+    default: gcc_unreachable ();
+    }
+
+  return (dw_t) ds;
+}
+
+dw_t
+get_dep_weak (ds_t ds, ds_t type)
+{
+  dw_t dw = get_dep_weak_1 (ds, type);
+
+  gcc_assert (MIN_DEP_WEAK <= dw && dw <= MAX_DEP_WEAK);
+  return dw;
+}
+
+/* Return the dep_status, which has the same parameters as DS, except for
+   speculative type TYPE, that will have weakness DW.  */
+ds_t
+set_dep_weak (ds_t ds, ds_t type, dw_t dw)
+{
+  gcc_assert (MIN_DEP_WEAK <= dw && dw <= MAX_DEP_WEAK);
+
+  ds &= ~type;
+  switch (type)
+    {
+    case BEGIN_DATA: ds |= ((ds_t) dw) << BEGIN_DATA_BITS_OFFSET; break;
+    case BE_IN_DATA: ds |= ((ds_t) dw) << BE_IN_DATA_BITS_OFFSET; break;
+    case BEGIN_CONTROL: ds |= ((ds_t) dw) << BEGIN_CONTROL_BITS_OFFSET; break;
+    case BE_IN_CONTROL: ds |= ((ds_t) dw) << BE_IN_CONTROL_BITS_OFFSET; break;
+    default: gcc_unreachable ();
+    }
+  return ds;
+}
+
+/* Return the join of two dep_statuses DS1 and DS2.
+   If MAX_P is true then choose the greater probability,
+   otherwise multiply probabilities.
+   This function assumes that both DS1 and DS2 contain speculative bits.  */
+static ds_t
+ds_merge_1 (ds_t ds1, ds_t ds2, bool max_p)
+{
+  ds_t ds, t;
+
+  gcc_assert ((ds1 & SPECULATIVE) && (ds2 & SPECULATIVE));
+
+  ds = (ds1 & DEP_TYPES) | (ds2 & DEP_TYPES);
+
+  t = FIRST_SPEC_TYPE;
+  do
+    {
+      if ((ds1 & t) && !(ds2 & t))
+	ds |= ds1 & t;
+      else if (!(ds1 & t) && (ds2 & t))
+	ds |= ds2 & t;
+      else if ((ds1 & t) && (ds2 & t))
+	{
+	  dw_t dw1 = get_dep_weak (ds1, t);
+	  dw_t dw2 = get_dep_weak (ds2, t);
+	  ds_t dw;
+
+	  if (!max_p)
+	    {
+	      dw = ((ds_t) dw1) * ((ds_t) dw2);
+	      dw /= MAX_DEP_WEAK;
+	      if (dw < MIN_DEP_WEAK)
+		dw = MIN_DEP_WEAK;
+	    }
+	  else
+	    {
+	      if (dw1 >= dw2)
+		dw = dw1;
+	      else
+		dw = dw2;
+	    }
+
+	  ds = set_dep_weak (ds, t, (dw_t) dw);
+	}
+
+      if (t == LAST_SPEC_TYPE)
+	break;
+      t <<= SPEC_TYPE_SHIFT;
+    }
+  while (1);
+
+  return ds;
+}
+
+/* Return the join of two dep_statuses DS1 and DS2.
+   This function assumes that both DS1 and DS2 contain speculative bits.  */
+ds_t
+ds_merge (ds_t ds1, ds_t ds2)
+{
+  return ds_merge_1 (ds1, ds2, false);
+}
+
+/* Return the join of two dep_statuses DS1 and DS2.  */
+ds_t
+ds_full_merge (ds_t ds, ds_t ds2, rtx mem1, rtx mem2)
+{
+  ds_t new_status = ds | ds2;
+
+  if (new_status & SPECULATIVE)
+    {
+      if ((ds && !(ds & SPECULATIVE))
+	  || (ds2 && !(ds2 & SPECULATIVE)))
+	/* Then this dep can't be speculative.  */
+	new_status &= ~SPECULATIVE;
+      else
+	{
+	  /* Both are speculative.  Merging probabilities.  */
+	  if (mem1)
+	    {
+	      dw_t dw;
+
+	      dw = estimate_dep_weak (mem1, mem2);
+	      ds = set_dep_weak (ds, BEGIN_DATA, dw);
+	    }
+
+	  if (!ds)
+	    new_status = ds2;
+	  else if (!ds2)
+	    new_status = ds;
+	  else
+	    new_status = ds_merge (ds2, ds);
+	}
+    }
+
+  return new_status;
+}
+
+/* Return the join of DS1 and DS2.  Use maximum instead of multiplying
+   probabilities.  */
+ds_t
+ds_max_merge (ds_t ds1, ds_t ds2)
+{
+  if (ds1 == 0 && ds2 == 0)
+    return 0;
+
+  if (ds1 == 0 && ds2 != 0)
+    return ds2;
+
+  if (ds1 != 0 && ds2 == 0)
+    return ds1;
+
+  return ds_merge_1 (ds1, ds2, true);
+}
+
+/* Return the probability of speculation success for the speculation
+   status DS.  */
+dw_t
+ds_weak (ds_t ds)
+{
+  ds_t res = 1, dt;
+  int n = 0;
+
+  dt = FIRST_SPEC_TYPE;
+  do
+    {
+      if (ds & dt)
+	{
+	  res *= (ds_t) get_dep_weak (ds, dt);
+	  n++;
+	}
+
+      if (dt == LAST_SPEC_TYPE)
+	break;
+      dt <<= SPEC_TYPE_SHIFT;
+    }
+  while (1);
+
+  gcc_assert (n);
+  while (--n)
+    res /= MAX_DEP_WEAK;
+
+  if (res < MIN_DEP_WEAK)
+    res = MIN_DEP_WEAK;
+
+  gcc_assert (res <= MAX_DEP_WEAK);
+
+  return (dw_t) res;
+}
+
+/* Return a dep status that contains all speculation types of DS.  */
+ds_t
+ds_get_speculation_types (ds_t ds)
+{
+  if (ds & BEGIN_DATA)
+    ds |= BEGIN_DATA;
+  if (ds & BE_IN_DATA)
+    ds |= BE_IN_DATA;
+  if (ds & BEGIN_CONTROL)
+    ds |= BEGIN_CONTROL;
+  if (ds & BE_IN_CONTROL)
+    ds |= BE_IN_CONTROL;
+
+  return ds & SPECULATIVE;
+}
+
+/* Return a dep status that contains maximal weakness for each speculation
+   type present in DS.  */
+ds_t
+ds_get_max_dep_weak (ds_t ds)
+{
+  if (ds & BEGIN_DATA)
+    ds = set_dep_weak (ds, BEGIN_DATA, MAX_DEP_WEAK);
+  if (ds & BE_IN_DATA)
+    ds = set_dep_weak (ds, BE_IN_DATA, MAX_DEP_WEAK);
+  if (ds & BEGIN_CONTROL)
+    ds = set_dep_weak (ds, BEGIN_CONTROL, MAX_DEP_WEAK);
+  if (ds & BE_IN_CONTROL)
+    ds = set_dep_weak (ds, BE_IN_CONTROL, MAX_DEP_WEAK);
+
+  return ds;
+}
+
+/* Dump information about the dependence status S.  */
+static void
+dump_ds (FILE *f, ds_t s)
+{
+  fprintf (f, "{");
+
+  if (s & BEGIN_DATA)
+    fprintf (f, "BEGIN_DATA: %d; ", get_dep_weak_1 (s, BEGIN_DATA));
+  if (s & BE_IN_DATA)
+    fprintf (f, "BE_IN_DATA: %d; ", get_dep_weak_1 (s, BE_IN_DATA));
+  if (s & BEGIN_CONTROL)
+    fprintf (f, "BEGIN_CONTROL: %d; ", get_dep_weak_1 (s, BEGIN_CONTROL));
+  if (s & BE_IN_CONTROL)
+    fprintf (f, "BE_IN_CONTROL: %d; ", get_dep_weak_1 (s, BE_IN_CONTROL));
+
+  if (s & HARD_DEP)
+    fprintf (f, "HARD_DEP; ");
+
+  if (s & DEP_TRUE)
+    fprintf (f, "DEP_TRUE; ");
+  if (s & DEP_ANTI)
+    fprintf (f, "DEP_ANTI; ");
+  if (s & DEP_OUTPUT)
+    fprintf (f, "DEP_OUTPUT; ");
+
+  fprintf (f, "}");
+}
+
+void
+debug_ds (ds_t s)
+{
+  dump_ds (stderr, s);
+  fprintf (stderr, "\n");
+}
+
+#ifdef ENABLE_CHECKING
+/* Verify that dependence type and status are consistent.
+   If RELAXED_P is true, then skip dep_weakness checks.  */
+static void
+check_dep (dep_t dep, bool relaxed_p)
+{
+  enum reg_note dt = DEP_TYPE (dep);
+  ds_t ds = DEP_STATUS (dep);
+
+  gcc_assert (DEP_PRO (dep) != DEP_CON (dep));
+
+  if (!(current_sched_info->flags & USE_DEPS_LIST))
+    {
+      gcc_assert (ds == -1);
+      return;
+    }
+
+  /* Check that dependence type contains the same bits as the status.  */
+  if (dt == REG_DEP_TRUE)
+    gcc_assert (ds & DEP_TRUE);
+  else if (dt == REG_DEP_OUTPUT)
+    gcc_assert ((ds & DEP_OUTPUT)
+		&& !(ds & DEP_TRUE));    
+  else 
+    gcc_assert ((dt == REG_DEP_ANTI)
+		&& (ds & DEP_ANTI)
+		&& !(ds & (DEP_OUTPUT | DEP_TRUE)));
+
+  /* HARD_DEP can not appear in dep_status of a link.  */
+  gcc_assert (!(ds & HARD_DEP));	  
+
+  /* Check that dependence status is set correctly when speculation is not
+     supported.  */
+  if (!sched_deps_info->generate_spec_deps)
+    gcc_assert (!(ds & SPECULATIVE));
+  else if (ds & SPECULATIVE)
+    {
+      if (!relaxed_p)
+	{
+	  ds_t type = FIRST_SPEC_TYPE;
+
+	  /* Check that dependence weakness is in proper range.  */
+	  do
+	    {
+	      if (ds & type)
+		get_dep_weak (ds, type);
+
+	      if (type == LAST_SPEC_TYPE)
+		break;
+	      type <<= SPEC_TYPE_SHIFT;
+	    }
+	  while (1);
+	}
+
+      if (ds & BEGIN_SPEC)
+	{
+	  /* Only true dependence can be data speculative.  */
+	  if (ds & BEGIN_DATA)
+	    gcc_assert (ds & DEP_TRUE);
+
+	  /* Control dependencies in the insn scheduler are represented by
+	     anti-dependencies, therefore only anti dependence can be
+	     control speculative.  */
+	  if (ds & BEGIN_CONTROL)
+	    gcc_assert (ds & DEP_ANTI);
+	}
+      else
+	{
+	  /* Subsequent speculations should resolve true dependencies.  */
+	  gcc_assert ((ds & DEP_TYPES) == DEP_TRUE);
+	}
+          
+      /* Check that true and anti dependencies can't have other speculative 
+	 statuses.  */
+      if (ds & DEP_TRUE)
+	gcc_assert (ds & (BEGIN_DATA | BE_IN_SPEC));
+      /* An output dependence can't be speculative at all.  */
+      gcc_assert (!(ds & DEP_OUTPUT));
+      if (ds & DEP_ANTI)
+	gcc_assert (ds & BEGIN_CONTROL);
+    }
+}
+#endif /* ENABLE_CHECKING */
+
+#endif /* INSN_SCHEDULING */