[multiple changes]

[gcc.git] / gcc / tree-flow-inline.h

/* Inline functions for tree-flow.h
   Copyright (C) 2001, 2003, 2005 Free Software Foundation, Inc.
   Contributed by Diego Novillo <dnovillo@redhat.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 2, 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 COPYING.  If not, write to
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.  */

#ifndef _TREE_FLOW_INLINE_H
#define _TREE_FLOW_INLINE_H 1

/* Inline functions for manipulating various data structures defined in
   tree-flow.h.  See tree-flow.h for documentation.  */

/* Initialize the hashtable iterator HTI to point to hashtable TABLE */

static inline void *
first_htab_element (htab_iterator *hti, htab_t table)
{
  hti->htab = table;
  hti->slot = table->entries;
  hti->limit = hti->slot + htab_size (table);
  do
    {
      PTR x = *(hti->slot);
      if (x != HTAB_EMPTY_ENTRY && x != HTAB_DELETED_ENTRY)
        break;
    } while (++(hti->slot) < hti->limit);
  
  if (hti->slot < hti->limit)
    return *(hti->slot);
  return NULL;
}

/* Return current non-empty/deleted slot of the hashtable pointed to by HTI,
   or NULL if we have  reached the end.  */

static inline bool
end_htab_p (htab_iterator *hti)
{
  if (hti->slot >= hti->limit)
    return true;
  return false;
}

/* Advance the hashtable iterator pointed by HTI to the next element of the
   hashtable.  */

static inline void *
next_htab_element (htab_iterator *hti)
{
  while (++(hti->slot) < hti->limit)
    {
      PTR x = *(hti->slot);
      if (x != HTAB_EMPTY_ENTRY && x != HTAB_DELETED_ENTRY)
        return x;
    };
  return NULL;
}

/* Initialize ITER to point to the first referenced variable in the
   referenced_vars hashtable, and return that variable.  */

static inline tree
first_referenced_var (referenced_var_iterator *iter)
{
  struct int_tree_map *itm;
  itm = first_htab_element (&iter->hti, referenced_vars);
  if (!itm) 
    return NULL;
  return itm->to;
}

/* Return true if we have hit the end of the referenced variables ITER is
   iterating through.  */

static inline bool
end_referenced_vars_p (referenced_var_iterator *iter)
{
  return end_htab_p (&iter->hti);
}

/* Make ITER point to the next referenced_var in the referenced_var hashtable,
   and return that variable.  */

static inline tree
next_referenced_var (referenced_var_iterator *iter)
{
  struct int_tree_map *itm;
  itm = next_htab_element (&iter->hti);
  if (!itm) 
    return NULL;
  return itm->to;
} 
 
/* Return the variable annotation for T, which must be a _DECL node.
   Return NULL if the variable annotation doesn't already exist.  */
static inline var_ann_t
var_ann (tree t)
{
  gcc_assert (t);
  gcc_assert (DECL_P (t));
  gcc_assert (!t->common.ann || t->common.ann->common.type == VAR_ANN);

  return (var_ann_t) t->common.ann;
}

/* Return the variable annotation for T, which must be a _DECL node.
   Create the variable annotation if it doesn't exist.  */
static inline var_ann_t
get_var_ann (tree var)
{
  var_ann_t ann = var_ann (var);
  return (ann) ? ann : create_var_ann (var);
}

/* Return the statement annotation for T, which must be a statement
   node.  Return NULL if the statement annotation doesn't exist.  */
static inline stmt_ann_t
stmt_ann (tree t)
{
#ifdef ENABLE_CHECKING
  gcc_assert (is_gimple_stmt (t));
#endif
  return (stmt_ann_t) t->common.ann;
}

/* Return the statement annotation for T, which must be a statement
   node.  Create the statement annotation if it doesn't exist.  */
static inline stmt_ann_t
get_stmt_ann (tree stmt)
{
  stmt_ann_t ann = stmt_ann (stmt);
  return (ann) ? ann : create_stmt_ann (stmt);
}

/* Return the annotation type for annotation ANN.  */
static inline enum tree_ann_type
ann_type (tree_ann_t ann)
{
  return ann->common.type;
}

/* Return the basic block for statement T.  */
static inline basic_block
bb_for_stmt (tree t)
{
  stmt_ann_t ann;

  if (TREE_CODE (t) == PHI_NODE)
    return PHI_BB (t);

  ann = stmt_ann (t);
  return ann ? ann->bb : NULL;
}

/* Return the may_aliases varray for variable VAR, or NULL if it has
   no may aliases.  */
static inline varray_type
may_aliases (tree var)
{
  var_ann_t ann = var_ann (var);
  return ann ? ann->may_aliases : NULL;
}

/* Return the line number for EXPR, or return -1 if we have no line
   number information for it.  */
static inline int
get_lineno (tree expr)
{
  if (expr == NULL_TREE)
    return -1;

  if (TREE_CODE (expr) == COMPOUND_EXPR)
    expr = TREE_OPERAND (expr, 0);

  if (! EXPR_HAS_LOCATION (expr))
    return -1;

  return EXPR_LINENO (expr);
}

/* Return the file name for EXPR, or return "???" if we have no
   filename information.  */
static inline const char *
get_filename (tree expr)
{
  const char *filename;
  if (expr == NULL_TREE)
    return "???";

  if (TREE_CODE (expr) == COMPOUND_EXPR)
    expr = TREE_OPERAND (expr, 0);

  if (EXPR_HAS_LOCATION (expr) && (filename = EXPR_FILENAME (expr)))
    return filename;
  else
    return "???";
}

/* Return true if T is a noreturn call.  */
static inline bool
noreturn_call_p (tree t)
{
  tree call = get_call_expr_in (t);
  return call != 0 && (call_expr_flags (call) & ECF_NORETURN) != 0;
}

/* Mark statement T as modified.  */
static inline void
mark_stmt_modified (tree t)
{
  stmt_ann_t ann;
  if (TREE_CODE (t) == PHI_NODE)
    return;

  ann = stmt_ann (t);
  if (ann == NULL)
    ann = create_stmt_ann (t);
  else if (noreturn_call_p (t))
    VEC_safe_push (tree, gc, modified_noreturn_calls, t);
  ann->modified = 1;
}

/* Mark statement T as modified, and update it.  */
static inline void
update_stmt (tree t)
{
  if (TREE_CODE (t) == PHI_NODE)
    return;
  mark_stmt_modified (t);
  update_stmt_operands (t);
}

static inline void
update_stmt_if_modified (tree t)
{
  if (stmt_modified_p (t))
    update_stmt_operands (t);
}

/* Return true if T is marked as modified, false otherwise.  */
static inline bool
stmt_modified_p (tree t)
{
  stmt_ann_t ann = stmt_ann (t);

  /* Note that if the statement doesn't yet have an annotation, we consider it
     modified.  This will force the next call to update_stmt_operands to scan 
     the statement.  */
  return ann ? ann->modified : true;
}

/* Delink an immediate_uses node from its chain.  */
static inline void
delink_imm_use (ssa_use_operand_t *linknode)
{
  /* Return if this node is not in a list.  */
  if (linknode->prev == NULL)
    return;

  linknode->prev->next = linknode->next;
  linknode->next->prev = linknode->prev;
  linknode->prev = NULL;
  linknode->next = NULL;
}

/* Link ssa_imm_use node LINKNODE into the chain for LIST.  */
static inline void
link_imm_use_to_list (ssa_use_operand_t *linknode, ssa_use_operand_t *list)
{
  /* Link the new node at the head of the list.  If we are in the process of 
     traversing the list, we won't visit any new nodes added to it.  */
  linknode->prev = list;
  linknode->next = list->next;
  list->next->prev = linknode;
  list->next = linknode;
}

/* Link ssa_imm_use node LINKNODE into the chain for DEF.  */
static inline void
link_imm_use (ssa_use_operand_t *linknode, tree def)
{
  ssa_use_operand_t *root;

  if (!def || TREE_CODE (def) != SSA_NAME)
    linknode->prev = NULL;
  else
    {
      root = &(SSA_NAME_IMM_USE_NODE (def));
#ifdef ENABLE_CHECKING
      if (linknode->use)
        gcc_assert (*(linknode->use) == def);
#endif
      link_imm_use_to_list (linknode, root);
    }
}

/* Set the value of a use pointed by USE to VAL.  */
static inline void
set_ssa_use_from_ptr (use_operand_p use, tree val)
{
  delink_imm_use (use);
  *(use->use) = val;
  link_imm_use (use, val);
}

/* Link ssa_imm_use node LINKNODE into the chain for DEF, with use occurring 
   in STMT.  */
static inline void
link_imm_use_stmt (ssa_use_operand_t *linknode, tree def, tree stmt)
{
  if (stmt)
    link_imm_use (linknode, def);
  else
    link_imm_use (linknode, NULL);
  linknode->stmt = stmt;
}

/* Relink a new node in place of an old node in the list.  */
static inline void
relink_imm_use (ssa_use_operand_t *node, ssa_use_operand_t *old)
{
  /* The node one had better be in the same list.  */
  gcc_assert (*(old->use) == *(node->use));
  node->prev = old->prev;
  node->next = old->next;
  if (old->prev)
    {
      old->prev->next = node;
      old->next->prev = node;
      /* Remove the old node from the list.  */
      old->prev = NULL;
    }
}

/* Relink ssa_imm_use node LINKNODE into the chain for OLD, with use occurring 
   in STMT.  */
static inline void
relink_imm_use_stmt (ssa_use_operand_t *linknode, ssa_use_operand_t *old, tree stmt)
{
  if (stmt)
    relink_imm_use (linknode, old);
  else
    link_imm_use (linknode, NULL);
  linknode->stmt = stmt;
}

/* Finished the traverse of an immediate use list IMM by removing it from 
   the list.  */
static inline void
end_safe_imm_use_traverse (imm_use_iterator *imm)
{
 delink_imm_use (&(imm->iter_node));
}

/* Return true if IMM is at the end of the list.  */
static inline bool
end_safe_imm_use_p (imm_use_iterator *imm)
{
  return (imm->imm_use == imm->end_p);
}

/* Initialize iterator IMM to process the list for VAR.  */
static inline use_operand_p
first_safe_imm_use (imm_use_iterator *imm, tree var)
{
  /* Set up and link the iterator node into the linked list for VAR.  */
  imm->iter_node.use = NULL;
  imm->iter_node.stmt = NULL_TREE;
  imm->end_p = &(SSA_NAME_IMM_USE_NODE (var));
  /* Check if there are 0 elements.  */
  if (imm->end_p->next == imm->end_p)
    {
      imm->imm_use = imm->end_p;
      return NULL_USE_OPERAND_P;
    }

  link_imm_use (&(imm->iter_node), var);
  imm->imm_use = imm->iter_node.next;
  return imm->imm_use;
}

/* Bump IMM to the next use in the list.  */
static inline use_operand_p
next_safe_imm_use (imm_use_iterator *imm)
{
  ssa_use_operand_t *ptr;
  use_operand_p old;

  old = imm->imm_use;
  /* If the next node following the iter_node is still the one referred to by
     imm_use, then the list hasn't changed, go to the next node.  */
  if (imm->iter_node.next == imm->imm_use)
    {
      ptr = &(imm->iter_node);
      /* Remove iternode from the list.  */
      delink_imm_use (ptr);
      imm->imm_use = imm->imm_use->next;
      if (! end_safe_imm_use_p (imm))
        {
          /* This isn't the end, link iternode before the next use.  */
          ptr->prev = imm->imm_use->prev;
          ptr->next = imm->imm_use;
          imm->imm_use->prev->next = ptr;
          imm->imm_use->prev = ptr;
        }
      else
        return old;
    }
  else
    {
      /* If the 'next' value after the iterator isn't the same as it was, then
         a node has been deleted, so we simply proceed to the node following 
         where the iterator is in the list.  */
      imm->imm_use = imm->iter_node.next;
      if (end_safe_imm_use_p (imm))
        {
          end_safe_imm_use_traverse (imm);
          return old;
        }
    }

  return imm->imm_use;
}

/* Return true is IMM has reached the end of the immediate use list.  */
static inline bool
end_readonly_imm_use_p (imm_use_iterator *imm)
{
  return (imm->imm_use == imm->end_p);
}

/* Initialize iterator IMM to process the list for VAR.  */
static inline use_operand_p
first_readonly_imm_use (imm_use_iterator *imm, tree var)
{
  gcc_assert (TREE_CODE (var) == SSA_NAME);

  imm->end_p = &(SSA_NAME_IMM_USE_NODE (var));
  imm->imm_use = imm->end_p->next;
#ifdef ENABLE_CHECKING
  imm->iter_node.next = imm->imm_use->next;
#endif
  if (end_readonly_imm_use_p (imm))
    return NULL_USE_OPERAND_P;
  return imm->imm_use;
}

/* Bump IMM to the next use in the list.  */
static inline use_operand_p
next_readonly_imm_use (imm_use_iterator *imm)
{
  use_operand_p old = imm->imm_use;

#ifdef ENABLE_CHECKING
  /* If this assertion fails, it indicates the 'next' pointer has changed 
     since we the last bump.  This indicates that the list is being modified
     via stmt changes, or SET_USE, or somesuch thing, and you need to be
     using the SAFE version of the iterator.  */
  gcc_assert (imm->iter_node.next == old->next);
  imm->iter_node.next = old->next->next;
#endif

  imm->imm_use = old->next;
  if (end_readonly_imm_use_p (imm))
    return old;
  return imm->imm_use;
}

/* Return true if VAR has no uses.  */
static inline bool
has_zero_uses (tree var)
{
  ssa_use_operand_t *ptr;
  ptr = &(SSA_NAME_IMM_USE_NODE (var));
  /* A single use means there is no items in the list.  */
  return (ptr == ptr->next);
}

/* Return true if VAR has a single use.  */
static inline bool
has_single_use (tree var)
{
  ssa_use_operand_t *ptr;
  ptr = &(SSA_NAME_IMM_USE_NODE (var));
  /* A single use means there is one item in the list.  */
  return (ptr != ptr->next && ptr == ptr->next->next);
}

/* If VAR has only a single immediate use, return true, and set USE_P and STMT
   to the use pointer and stmt of occurrence.  */
static inline bool
single_imm_use (tree var, use_operand_p *use_p, tree *stmt)
{
  ssa_use_operand_t *ptr;

  ptr = &(SSA_NAME_IMM_USE_NODE (var));
  if (ptr != ptr->next && ptr == ptr->next->next)
    {
      *use_p = ptr->next;
      *stmt = ptr->next->stmt;
      return true;
    }
  *use_p = NULL_USE_OPERAND_P;
  *stmt = NULL_TREE;
  return false;
}

/* Return the number of immediate uses of VAR.  */
static inline unsigned int
num_imm_uses (tree var)
{
  ssa_use_operand_t *ptr, *start;
  unsigned int num;

  start = &(SSA_NAME_IMM_USE_NODE (var));
  num = 0;
  for (ptr = start->next; ptr != start; ptr = ptr->next)
     num++;

  return num;
}


/* Return the tree pointer to by USE.  */ 
static inline tree
get_use_from_ptr (use_operand_p use)
{ 
  return *(use->use);
} 

/* Return the tree pointer to by DEF.  */
static inline tree
get_def_from_ptr (def_operand_p def)
{
  return *def;
}

/* Return a def_operand_p pointer for the result of PHI.  */
static inline def_operand_p
get_phi_result_ptr (tree phi)
{
  return &(PHI_RESULT_TREE (phi));
}

/* Return a use_operand_p pointer for argument I of phinode PHI.  */
static inline use_operand_p
get_phi_arg_def_ptr (tree phi, int i)
{
  return &(PHI_ARG_IMM_USE_NODE (phi,i));
}


/* Return the bitmap of addresses taken by STMT, or NULL if it takes
   no addresses.  */
static inline bitmap
addresses_taken (tree stmt)
{
  stmt_ann_t ann = stmt_ann (stmt);
  return ann ? ann->addresses_taken : NULL;
}

/* Return the PHI nodes for basic block BB, or NULL if there are no
   PHI nodes.  */
static inline tree
phi_nodes (basic_block bb)
{
  return bb->phi_nodes;
}

/* Set list of phi nodes of a basic block BB to L.  */

static inline void
set_phi_nodes (basic_block bb, tree l)
{
  tree phi;

  bb->phi_nodes = l;
  for (phi = l; phi; phi = PHI_CHAIN (phi))
    set_bb_for_stmt (phi, bb);
}

/* Return the phi argument which contains the specified use.  */

static inline int
phi_arg_index_from_use (use_operand_p use)
{
  struct phi_arg_d *element, *root;
  int index;
  tree phi;

  /* Since the use is the first thing in a PHI argument element, we can
     calculate its index based on casting it to an argument, and performing
     pointer arithmetic.  */

  phi = USE_STMT (use);
  gcc_assert (TREE_CODE (phi) == PHI_NODE);

  element = (struct phi_arg_d *)use;
  root = &(PHI_ARG_ELT (phi, 0));
  index = element - root;

#ifdef ENABLE_CHECKING
  /* Make sure the calculation doesn't have any leftover bytes.  If it does, 
     then imm_use is likely not the first element in phi_arg_d.  */
  gcc_assert (
          (((char *)element - (char *)root) % sizeof (struct phi_arg_d)) == 0);
  gcc_assert (index >= 0 && index < PHI_ARG_CAPACITY (phi));
#endif
 
 return index;
}

/* Mark VAR as used, so that it'll be preserved during rtl expansion.  */

static inline void
set_is_used (tree var)
{
  var_ann_t ann = get_var_ann (var);
  ann->used = 1;
}


/*  -----------------------------------------------------------------------  */

/* Return true if T is an executable statement.  */
static inline bool
is_exec_stmt (tree t)
{
  return (t && !IS_EMPTY_STMT (t) && t != error_mark_node);
}


/* Return true if this stmt can be the target of a control transfer stmt such
   as a goto.  */
static inline bool
is_label_stmt (tree t)
{
  if (t)
    switch (TREE_CODE (t))
      {
        case LABEL_DECL:
        case LABEL_EXPR:
        case CASE_LABEL_EXPR:
          return true;
        default:
          return false;
      }
  return false;
}

/* Set the default definition for VAR to DEF.  */
static inline void
set_default_def (tree var, tree def)
{
  var_ann_t ann = get_var_ann (var);
  ann->default_def = def;
}

/* Return the default definition for variable VAR, or NULL if none
   exists.  */
static inline tree
default_def (tree var)
{
  var_ann_t ann = var_ann (var);
  return ann ? ann->default_def : NULL_TREE;
}

/* PHI nodes should contain only ssa_names and invariants.  A test
   for ssa_name is definitely simpler; don't let invalid contents
   slip in in the meantime.  */

static inline bool
phi_ssa_name_p (tree t)
{
  if (TREE_CODE (t) == SSA_NAME)
    return true;
#ifdef ENABLE_CHECKING
  gcc_assert (is_gimple_min_invariant (t));
#endif
  return false;
}

/*  -----------------------------------------------------------------------  */

/* Return a block_stmt_iterator that points to beginning of basic
   block BB.  */
static inline block_stmt_iterator
bsi_start (basic_block bb)
{
  block_stmt_iterator bsi;
  if (bb->stmt_list)
    bsi.tsi = tsi_start (bb->stmt_list);
  else
    {
      gcc_assert (bb->index < 0);
      bsi.tsi.ptr = NULL;
      bsi.tsi.container = NULL;
    }
  bsi.bb = bb;
  return bsi;
}

/* Return a block statement iterator that points to the last label in
   block BB.  */

static inline block_stmt_iterator
bsi_after_labels (basic_block bb)
{
  block_stmt_iterator bsi;
  tree_stmt_iterator next;

  bsi.bb = bb;

  if (!bb->stmt_list)
    {
      gcc_assert (bb->index < 0);
      bsi.tsi.ptr = NULL;
      bsi.tsi.container = NULL;
      return bsi;
    }

  bsi.tsi = tsi_start (bb->stmt_list);
  if (tsi_end_p (bsi.tsi))
    return bsi;

  /* Ensure that there are some labels.  The rationale is that we want
     to insert after the bsi that is returned, and these insertions should
     be placed at the start of the basic block.  This would not work if the
     first statement was not label; rather fail here than enable the user
     proceed in wrong way.  */
  gcc_assert (TREE_CODE (tsi_stmt (bsi.tsi)) == LABEL_EXPR);

  next = bsi.tsi;
  tsi_next (&next);

  while (!tsi_end_p (next)
         && TREE_CODE (tsi_stmt (next)) == LABEL_EXPR)
    {
      bsi.tsi = next;
      tsi_next (&next);
    }

  return bsi;
}

/* Return a block statement iterator that points to the end of basic
   block BB.  */
static inline block_stmt_iterator
bsi_last (basic_block bb)
{
  block_stmt_iterator bsi;
  if (bb->stmt_list)
    bsi.tsi = tsi_last (bb->stmt_list);
  else
    {
      gcc_assert (bb->index < 0);
      bsi.tsi.ptr = NULL;
      bsi.tsi.container = NULL;
    }
  bsi.bb = bb;
  return bsi;
}

/* Return true if block statement iterator I has reached the end of
   the basic block.  */
static inline bool
bsi_end_p (block_stmt_iterator i)
{
  return tsi_end_p (i.tsi);
}

/* Modify block statement iterator I so that it is at the next
   statement in the basic block.  */
static inline void
bsi_next (block_stmt_iterator *i)
{
  tsi_next (&i->tsi);
}

/* Modify block statement iterator I so that it is at the previous
   statement in the basic block.  */
static inline void
bsi_prev (block_stmt_iterator *i)
{
  tsi_prev (&i->tsi);
}

/* Return the statement that block statement iterator I is currently
   at.  */
static inline tree
bsi_stmt (block_stmt_iterator i)
{
  return tsi_stmt (i.tsi);
}

/* Return a pointer to the statement that block statement iterator I
   is currently at.  */
static inline tree *
bsi_stmt_ptr (block_stmt_iterator i)
{
  return tsi_stmt_ptr (i.tsi);
}

/* Returns the loop of the statement STMT.  */

static inline struct loop *
loop_containing_stmt (tree stmt)
{
  basic_block bb = bb_for_stmt (stmt);
  if (!bb)
    return NULL;

  return bb->loop_father;
}

/* Return true if VAR is a clobbered by function calls.  */
static inline bool
is_call_clobbered (tree var)
{
  return is_global_var (var)
    || bitmap_bit_p (call_clobbered_vars, DECL_UID (var));
}

/* Mark variable VAR as being clobbered by function calls.  */
static inline void
mark_call_clobbered (tree var)
{
  var_ann_t ann = var_ann (var);
  /* If VAR is a memory tag, then we need to consider it a global
     variable.  This is because the pointer that VAR represents has
     been found to point to either an arbitrary location or to a known
     location in global memory.  */
  if (ann->mem_tag_kind != NOT_A_TAG && ann->mem_tag_kind != STRUCT_FIELD)
    DECL_EXTERNAL (var) = 1;
  bitmap_set_bit (call_clobbered_vars, DECL_UID (var));
  ssa_call_clobbered_cache_valid = false;
  ssa_ro_call_cache_valid = false;
}

/* Clear the call-clobbered attribute from variable VAR.  */
static inline void
clear_call_clobbered (tree var)
{
  var_ann_t ann = var_ann (var);
  if (ann->mem_tag_kind != NOT_A_TAG && ann->mem_tag_kind != STRUCT_FIELD)
    DECL_EXTERNAL (var) = 0;
  bitmap_clear_bit (call_clobbered_vars, DECL_UID (var));
  ssa_call_clobbered_cache_valid = false;
  ssa_ro_call_cache_valid = false;
}

/* Mark variable VAR as being non-addressable.  */
static inline void
mark_non_addressable (tree var)
{
  bitmap_clear_bit (call_clobbered_vars, DECL_UID (var));
  TREE_ADDRESSABLE (var) = 0;
  ssa_call_clobbered_cache_valid = false;
  ssa_ro_call_cache_valid = false;
}

/* Return the common annotation for T.  Return NULL if the annotation
   doesn't already exist.  */
static inline tree_ann_t
tree_ann (tree t)
{
  return t->common.ann;
}

/* Return a common annotation for T.  Create the constant annotation if it
   doesn't exist.  */
static inline tree_ann_t
get_tree_ann (tree t)
{
  tree_ann_t ann = tree_ann (t);
  return (ann) ? ann : create_tree_ann (t);
}

/*  -----------------------------------------------------------------------  */

/* The following set of routines are used to iterator over various type of
   SSA operands.  */

/* Return true if PTR is finished iterating.  */
static inline bool
op_iter_done (ssa_op_iter *ptr)
{
  return ptr->done;
}

/* Get the next iterator use value for PTR.  */
static inline use_operand_p
op_iter_next_use (ssa_op_iter *ptr)
{
  use_operand_p use_p;
#ifdef ENABLE_CHECKING
  gcc_assert (ptr->iter_type == ssa_op_iter_use);
#endif
  if (ptr->uses)
    {
      use_p = USE_OP_PTR (ptr->uses);
      ptr->uses = ptr->uses->next;
      return use_p;
    }
  if (ptr->vuses)
    {
      use_p = VUSE_OP_PTR (ptr->vuses);
      ptr->vuses = ptr->vuses->next;
      return use_p;
    }
  if (ptr->mayuses)
    {
      use_p = MAYDEF_OP_PTR (ptr->mayuses);
      ptr->mayuses = ptr->mayuses->next;
      return use_p;
    }
  if (ptr->mustkills)
    {
      use_p = MUSTDEF_KILL_PTR (ptr->mustkills);
      ptr->mustkills = ptr->mustkills->next;
      return use_p;
    }
  if (ptr->phi_i < ptr->num_phi)
    {
      return PHI_ARG_DEF_PTR (ptr->phi_stmt, (ptr->phi_i)++);
    }
  ptr->done = true;
  return NULL_USE_OPERAND_P;
}

/* Get the next iterator def value for PTR.  */
static inline def_operand_p
op_iter_next_def (ssa_op_iter *ptr)
{
  def_operand_p def_p;
#ifdef ENABLE_CHECKING
  gcc_assert (ptr->iter_type == ssa_op_iter_def);
#endif
  if (ptr->defs)
    {
      def_p = DEF_OP_PTR (ptr->defs);
      ptr->defs = ptr->defs->next;
      return def_p;
    }
  if (ptr->mustdefs)
    {
      def_p = MUSTDEF_RESULT_PTR (ptr->mustdefs);
      ptr->mustdefs = ptr->mustdefs->next;
      return def_p;
    }
  if (ptr->maydefs)
    {
      def_p = MAYDEF_RESULT_PTR (ptr->maydefs);
      ptr->maydefs = ptr->maydefs->next;
      return def_p;
    }
  ptr->done = true;
  return NULL_DEF_OPERAND_P;
}

/* Get the next iterator tree value for PTR.  */
static inline tree
op_iter_next_tree (ssa_op_iter *ptr)
{
  tree val;
#ifdef ENABLE_CHECKING
  gcc_assert (ptr->iter_type == ssa_op_iter_tree);
#endif
  if (ptr->uses)
    {
      val = USE_OP (ptr->uses);
      ptr->uses = ptr->uses->next;
      return val;
    }
  if (ptr->vuses)
    {
      val = VUSE_OP (ptr->vuses);
      ptr->vuses = ptr->vuses->next;
      return val;
    }
  if (ptr->mayuses)
    {
      val = MAYDEF_OP (ptr->mayuses);
      ptr->mayuses = ptr->mayuses->next;
      return val;
    }
  if (ptr->mustkills)
    {
      val = MUSTDEF_KILL (ptr->mustkills);
      ptr->mustkills = ptr->mustkills->next;
      return val;
    }
  if (ptr->defs)
    {
      val = DEF_OP (ptr->defs);
      ptr->defs = ptr->defs->next;
      return val;
    }
  if (ptr->mustdefs)
    {
      val = MUSTDEF_RESULT (ptr->mustdefs);
      ptr->mustdefs = ptr->mustdefs->next;
      return val;
    }
  if (ptr->maydefs)
    {
      val = MAYDEF_RESULT (ptr->maydefs);
      ptr->maydefs = ptr->maydefs->next;
      return val;
    }

  ptr->done = true;
  return NULL_TREE;

}


/* This functions clears the iterator PTR, and marks it done.  This is normally
   used to prevent warnings in the compile about might be uninitailzied
   components.  */

static inline void
clear_and_done_ssa_iter (ssa_op_iter *ptr)
{
  ptr->defs = NULL;
  ptr->uses = NULL;
  ptr->vuses = NULL;
  ptr->maydefs = NULL;
  ptr->mayuses = NULL;
  ptr->mustdefs = NULL;
  ptr->mustkills = NULL;
  ptr->iter_type = ssa_op_iter_none;
  ptr->phi_i = 0;
  ptr->num_phi = 0;
  ptr->phi_stmt = NULL_TREE;
  ptr->done = true;
}

/* Initialize the iterator PTR to the virtual defs in STMT.  */
static inline void
op_iter_init (ssa_op_iter *ptr, tree stmt, int flags)
{
#ifdef ENABLE_CHECKING
  gcc_assert (stmt_ann (stmt));
#endif

  ptr->defs = (flags & SSA_OP_DEF) ? DEF_OPS (stmt) : NULL;
  ptr->uses = (flags & SSA_OP_USE) ? USE_OPS (stmt) : NULL;
  ptr->vuses = (flags & SSA_OP_VUSE) ? VUSE_OPS (stmt) : NULL;
  ptr->maydefs = (flags & SSA_OP_VMAYDEF) ? MAYDEF_OPS (stmt) : NULL;
  ptr->mayuses = (flags & SSA_OP_VMAYUSE) ? MAYDEF_OPS (stmt) : NULL;
  ptr->mustdefs = (flags & SSA_OP_VMUSTDEF) ? MUSTDEF_OPS (stmt) : NULL;
  ptr->mustkills = (flags & SSA_OP_VMUSTKILL) ? MUSTDEF_OPS (stmt) : NULL;
  ptr->done = false;

  ptr->phi_i = 0;
  ptr->num_phi = 0;
  ptr->phi_stmt = NULL_TREE;
}

/* Initialize iterator PTR to the use operands in STMT based on FLAGS. Return
   the first use.  */
static inline use_operand_p
op_iter_init_use (ssa_op_iter *ptr, tree stmt, int flags)
{
  gcc_assert ((flags & SSA_OP_ALL_DEFS) == 0);
  op_iter_init (ptr, stmt, flags);
  ptr->iter_type = ssa_op_iter_use;
  return op_iter_next_use (ptr);
}

/* Initialize iterator PTR to the def operands in STMT based on FLAGS. Return
   the first def.  */
static inline def_operand_p
op_iter_init_def (ssa_op_iter *ptr, tree stmt, int flags)
{
  gcc_assert ((flags & (SSA_OP_ALL_USES | SSA_OP_VIRTUAL_KILLS)) == 0);
  op_iter_init (ptr, stmt, flags);
  ptr->iter_type = ssa_op_iter_def;
  return op_iter_next_def (ptr);
}

/* Initialize iterator PTR to the operands in STMT based on FLAGS. Return
   the first operand as a tree.  */
static inline tree
op_iter_init_tree (ssa_op_iter *ptr, tree stmt, int flags)
{
  op_iter_init (ptr, stmt, flags);
  ptr->iter_type = ssa_op_iter_tree;
  return op_iter_next_tree (ptr);
}

/* Get the next iterator mustdef value for PTR, returning the mustdef values in
   KILL and DEF.  */
static inline void
op_iter_next_maymustdef (use_operand_p *use, def_operand_p *def, 
                         ssa_op_iter *ptr)
{
#ifdef ENABLE_CHECKING
  gcc_assert (ptr->iter_type == ssa_op_iter_maymustdef);
#endif
  if (ptr->mayuses)
    {
      *def = MAYDEF_RESULT_PTR (ptr->mayuses);
      *use = MAYDEF_OP_PTR (ptr->mayuses);
      ptr->mayuses = ptr->mayuses->next;
      return;
    }

  if (ptr->mustkills)
    {
      *def = MUSTDEF_RESULT_PTR (ptr->mustkills);
      *use = MUSTDEF_KILL_PTR (ptr->mustkills);
      ptr->mustkills = ptr->mustkills->next;
      return;
    }

  *def = NULL_DEF_OPERAND_P;
  *use = NULL_USE_OPERAND_P;
  ptr->done = true;
  return;
}


/* Initialize iterator PTR to the operands in STMT.  Return the first operands
   in USE and DEF.  */
static inline void
op_iter_init_maydef (ssa_op_iter *ptr, tree stmt, use_operand_p *use, 
                     def_operand_p *def)
{
  gcc_assert (TREE_CODE (stmt) != PHI_NODE);

  op_iter_init (ptr, stmt, SSA_OP_VMAYUSE);
  ptr->iter_type = ssa_op_iter_maymustdef;
  op_iter_next_maymustdef (use, def, ptr);
}


/* Initialize iterator PTR to the operands in STMT.  Return the first operands
   in KILL and DEF.  */
static inline void
op_iter_init_mustdef (ssa_op_iter *ptr, tree stmt, use_operand_p *kill, 
                     def_operand_p *def)
{
  gcc_assert (TREE_CODE (stmt) != PHI_NODE);

  op_iter_init (ptr, stmt, SSA_OP_VMUSTKILL);
  ptr->iter_type = ssa_op_iter_maymustdef;
  op_iter_next_maymustdef (kill, def, ptr);
}

/* Initialize iterator PTR to the operands in STMT.  Return the first operands
   in KILL and DEF.  */
static inline void
op_iter_init_must_and_may_def (ssa_op_iter *ptr, tree stmt,
                               use_operand_p *kill, def_operand_p *def)
{
  gcc_assert (TREE_CODE (stmt) != PHI_NODE);

  op_iter_init (ptr, stmt, SSA_OP_VMUSTKILL|SSA_OP_VMAYUSE);
  ptr->iter_type = ssa_op_iter_maymustdef;
  op_iter_next_maymustdef (kill, def, ptr);
}


/* If there is a single operand in STMT matching FLAGS, return it.  Otherwise
   return NULL.  PTR is the iterator to use.  */
static inline tree
single_ssa_tree_operand (tree stmt, int flags)
{
  tree var;
  ssa_op_iter iter;

  var = op_iter_init_tree (&iter, stmt, flags);
  if (op_iter_done (&iter))
    return NULL_TREE;
  op_iter_next_tree (&iter);
  if (op_iter_done (&iter))
    return var;
  return NULL_TREE;
}


/* If there is a single operand in STMT matching FLAGS, return it.  Otherwise
   return NULL.  PTR is the iterator to use.  */
static inline use_operand_p
single_ssa_use_operand (tree stmt, int flags)
{
  use_operand_p var;
  ssa_op_iter iter;

  var = op_iter_init_use (&iter, stmt, flags);
  if (op_iter_done (&iter))
    return NULL_USE_OPERAND_P;
  op_iter_next_use (&iter);
  if (op_iter_done (&iter))
    return var;
  return NULL_USE_OPERAND_P;
}



/* If there is a single operand in STMT matching FLAGS, return it.  Otherwise
   return NULL.  PTR is the iterator to use.  */
static inline def_operand_p
single_ssa_def_operand (tree stmt, int flags)
{
  def_operand_p var;
  ssa_op_iter iter;

  var = op_iter_init_def (&iter, stmt, flags);
  if (op_iter_done (&iter))
    return NULL_DEF_OPERAND_P;
  op_iter_next_def (&iter);
  if (op_iter_done (&iter))
    return var;
  return NULL_DEF_OPERAND_P;
}


/* If there is a single operand in STMT matching FLAGS, return it.  Otherwise
   return NULL.  PTR is the iterator to use.  */
static inline bool
zero_ssa_operands (tree stmt, int flags)
{
  ssa_op_iter iter;

  op_iter_init_tree (&iter, stmt, flags);
  return op_iter_done (&iter);
}


/* Return the number of operands matching FLAGS in STMT.  */
static inline int
num_ssa_operands (tree stmt, int flags)
{
  ssa_op_iter iter;
  tree t;
  int num = 0;

  FOR_EACH_SSA_TREE_OPERAND (t, stmt, iter, flags)
    num++;
  return num;
}


/* Delink all immediate_use information for STMT.  */
static inline void
delink_stmt_imm_use (tree stmt)
{
   ssa_op_iter iter;
   use_operand_p use_p;

   if (ssa_operands_active ())
     FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
                               (SSA_OP_ALL_USES | SSA_OP_ALL_KILLS))
       delink_imm_use (use_p);
}


/* This routine will compare all the operands matching FLAGS in STMT1 to those
   in STMT2.  TRUE is returned if they are the same.  STMTs can be NULL.  */
static inline bool
compare_ssa_operands_equal (tree stmt1, tree stmt2, int flags)
{
  ssa_op_iter iter1, iter2;
  tree op1 = NULL_TREE;
  tree op2 = NULL_TREE;
  bool look1, look2;

  if (stmt1 == stmt2)
    return true;

  look1 = stmt1 && stmt_ann (stmt1);
  look2 = stmt2 && stmt_ann (stmt2);

  if (look1)
    {
      op1 = op_iter_init_tree (&iter1, stmt1, flags);
      if (!look2)
        return op_iter_done (&iter1);
    }
  else
    clear_and_done_ssa_iter (&iter1);

  if (look2)
    {
      op2 = op_iter_init_tree (&iter2, stmt2, flags);
      if (!look1)
        return op_iter_done (&iter2);
    }
  else
    clear_and_done_ssa_iter (&iter2);

  while (!op_iter_done (&iter1) && !op_iter_done (&iter2))
    {
      if (op1 != op2)
        return false;
      op1 = op_iter_next_tree (&iter1);
      op2 = op_iter_next_tree (&iter2);
    }

  return (op_iter_done (&iter1) && op_iter_done (&iter2));
}


/* If there is a single DEF in the PHI node which matches FLAG, return it.
   Otherwise return NULL_DEF_OPERAND_P.  */
static inline tree
single_phi_def (tree stmt, int flags)
{
  tree def = PHI_RESULT (stmt);
  if ((flags & SSA_OP_DEF) && is_gimple_reg (def)) 
    return def;
  if ((flags & SSA_OP_VIRTUAL_DEFS) && !is_gimple_reg (def))
    return def;
  return NULL_TREE;
}

/* Initialize the iterator PTR for uses matching FLAGS in PHI.  FLAGS should
   be either SSA_OP_USES or SAS_OP_VIRTUAL_USES.  */
static inline use_operand_p
op_iter_init_phiuse (ssa_op_iter *ptr, tree phi, int flags)
{
  tree phi_def = PHI_RESULT (phi);
  int comp;

  clear_and_done_ssa_iter (ptr);
  ptr->done = false;

  gcc_assert ((flags & (SSA_OP_USE | SSA_OP_VIRTUAL_USES)) != 0);

  comp = (is_gimple_reg (phi_def) ? SSA_OP_USE : SSA_OP_VIRTUAL_USES);
    
  /* If the PHI node doesn't the operand type we care about, we're done.  */
  if ((flags & comp) == 0)
    {
      ptr->done = true;
      return NULL_USE_OPERAND_P;
    }

  ptr->phi_stmt = phi;
  ptr->num_phi = PHI_NUM_ARGS (phi);
  ptr->iter_type = ssa_op_iter_use;
  return op_iter_next_use (ptr);
}


/* Start an iterator for a PHI definition.  */

static inline def_operand_p
op_iter_init_phidef (ssa_op_iter *ptr, tree phi, int flags)
{
  tree phi_def = PHI_RESULT (phi);
  int comp;

  clear_and_done_ssa_iter (ptr);
  ptr->done = false;

  gcc_assert ((flags & (SSA_OP_DEF | SSA_OP_VIRTUAL_DEFS)) != 0);

  comp = (is_gimple_reg (phi_def) ? SSA_OP_DEF : SSA_OP_VIRTUAL_DEFS);
    
  /* If the PHI node doesn't the operand type we care about, we're done.  */
  if ((flags & comp) == 0)
    {
      ptr->done = true;
      return NULL_USE_OPERAND_P;
    }

  ptr->iter_type = ssa_op_iter_def;
  /* The first call to op_iter_next_def will terminate the iterator since
     all the fields are NULL.  Simply return the result here as the first and
     therefore only result.  */
  return PHI_RESULT_PTR (phi);
}



/* Return true if VAR cannot be modified by the program.  */

static inline bool
unmodifiable_var_p (tree var)
{
  if (TREE_CODE (var) == SSA_NAME)
    var = SSA_NAME_VAR (var);
  return TREE_READONLY (var) && (TREE_STATIC (var) || DECL_EXTERNAL (var));
}

/* Return true if REF, a COMPONENT_REF, has an ARRAY_REF somewhere in it.  */

static inline bool
ref_contains_array_ref (tree ref)
{
  while (handled_component_p (ref))
    {
      if (TREE_CODE (ref) == ARRAY_REF)
        return true;
      ref = TREE_OPERAND (ref, 0);
    }
  return false;
}

/* Given a variable VAR, lookup and return a pointer to the list of
   subvariables for it.  */

static inline subvar_t *
lookup_subvars_for_var (tree var)
{
  var_ann_t ann = var_ann (var);
  gcc_assert (ann);
  return &ann->subvars;
}

/* Given a variable VAR, return a linked list of subvariables for VAR, or
   NULL, if there are no subvariables.  */

static inline subvar_t
get_subvars_for_var (tree var)
{
  subvar_t subvars;

  gcc_assert (SSA_VAR_P (var));  
  
  if (TREE_CODE (var) == SSA_NAME)
    subvars = *(lookup_subvars_for_var (SSA_NAME_VAR (var)));
  else
    subvars = *(lookup_subvars_for_var (var));
  return subvars;
}

/* Return true if V is a tree that we can have subvars for.
   Normally, this is any aggregate type, however, due to implementation
   limitations ATM, we exclude array types as well.  */

static inline bool
var_can_have_subvars (tree v)
{
  return (AGGREGATE_TYPE_P (TREE_TYPE (v)) &&
          TREE_CODE (TREE_TYPE (v)) != ARRAY_TYPE);
}

  
/* Return true if OFFSET and SIZE define a range that overlaps with some
   portion of the range of SV, a subvar.  If there was an exact overlap,
   *EXACT will be set to true upon return. */

static inline bool
overlap_subvar (HOST_WIDE_INT offset, HOST_WIDE_INT size,
                subvar_t sv,  bool *exact)
{
  /* There are three possible cases of overlap.
     1. We can have an exact overlap, like so:   
     |offset, offset + size             |
     |sv->offset, sv->offset + sv->size |
     
     2. We can have offset starting after sv->offset, like so:
     
           |offset, offset + size              |
     |sv->offset, sv->offset + sv->size  |

     3. We can have offset starting before sv->offset, like so:
     
     |offset, offset + size    |
       |sv->offset, sv->offset + sv->size|
  */

  if (exact)
    *exact = false;
  if (offset == sv->offset && size == sv->size)
    {
      if (exact)
        *exact = true;
      return true;
    }
  else if (offset >= sv->offset && offset < (sv->offset + sv->size))
    {
      return true;
    }
  else if (offset < sv->offset && (offset + size > sv->offset))
    {
      return true;
    }
  return false;

}

#endif /* _TREE_FLOW_INLINE_H  */