diff gcc/ssa-iterators.h @ 16:04ced10e8804

gcc 7
author kono
date Fri, 27 Oct 2017 22:46:09 +0900
parents
children 84e7813d76e9
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ssa-iterators.h	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,1004 @@
+/* Header file for SSA iterators.
+   Copyright (C) 2013-2017 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_SSA_ITERATORS_H
+#define GCC_SSA_ITERATORS_H
+
+/* Immediate use lists are used to directly access all uses for an SSA
+   name and get pointers to the statement for each use.
+
+   The structure ssa_use_operand_t consists of PREV and NEXT pointers
+   to maintain the list.  A USE pointer, which points to address where
+   the use is located and a LOC pointer which can point to the
+   statement where the use is located, or, in the case of the root
+   node, it points to the SSA name itself.
+
+   The list is anchored by an occurrence of ssa_operand_d *in* the
+   ssa_name node itself (named 'imm_uses').  This node is uniquely
+   identified by having a NULL USE pointer. and the LOC pointer
+   pointing back to the ssa_name node itself.  This node forms the
+   base for a circular list, and initially this is the only node in
+   the list.
+
+   Fast iteration allows each use to be examined, but does not allow
+   any modifications to the uses or stmts.
+
+   Normal iteration allows insertion, deletion, and modification. the
+   iterator manages this by inserting a marker node into the list
+   immediately before the node currently being examined in the list.
+   this marker node is uniquely identified by having null stmt *and* a
+   null use pointer.
+
+   When iterating to the next use, the iteration routines check to see
+   if the node after the marker has changed. if it has, then the node
+   following the marker is now the next one to be visited. if not, the
+   marker node is moved past that node in the list (visualize it as
+   bumping the marker node through the list).  this continues until
+   the marker node is moved to the original anchor position. the
+   marker node is then removed from the list.
+
+   If iteration is halted early, the marker node must be removed from
+   the list before continuing.  */
+struct imm_use_iterator
+{
+  /* This is the current use the iterator is processing.  */
+  ssa_use_operand_t *imm_use;
+  /* This marks the last use in the list (use node from SSA_NAME)  */
+  ssa_use_operand_t *end_p;
+  /* This node is inserted and used to mark the end of the uses for a stmt.  */
+  ssa_use_operand_t iter_node;
+  /* This is the next ssa_name to visit.  IMM_USE may get removed before
+     the next one is traversed to, so it must be cached early.  */
+  ssa_use_operand_t *next_imm_name;
+};
+
+
+/* Use this iterator when simply looking at stmts.  Adding, deleting or
+   modifying stmts will cause this iterator to malfunction.  */
+
+#define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)		\
+  for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));	\
+       !end_readonly_imm_use_p (&(ITER));			\
+       (void) ((DEST) = next_readonly_imm_use (&(ITER))))
+
+/* Use this iterator to visit each stmt which has a use of SSAVAR.  */
+
+#define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)		\
+  for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));		\
+       !end_imm_use_stmt_p (&(ITER));				\
+       (void) ((STMT) = next_imm_use_stmt (&(ITER))))
+
+/* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
+   do so will result in leaving a iterator marker node in the immediate
+   use list, and nothing good will come from that.   */
+#define BREAK_FROM_IMM_USE_STMT(ITER)				\
+   {								\
+     end_imm_use_stmt_traverse (&(ITER));			\
+     break;							\
+   }
+
+
+/* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
+   get access to each occurrence of ssavar on the stmt returned by
+   that iterator..  for instance:
+
+     FOR_EACH_IMM_USE_STMT (stmt, iter, ssavar)
+       {
+         FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+	   {
+	     SET_USE (use_p, blah);
+	   }
+	 update_stmt (stmt);
+       }							 */
+
+#define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)			\
+  for ((DEST) = first_imm_use_on_stmt (&(ITER));		\
+       !end_imm_use_on_stmt_p (&(ITER));			\
+       (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
+
+
+
+extern bool single_imm_use_1 (const ssa_use_operand_t *head,
+			      use_operand_p *use_p, gimple **stmt);
+
+
+enum ssa_op_iter_type {
+  ssa_op_iter_none = 0,
+  ssa_op_iter_tree,
+  ssa_op_iter_use,
+  ssa_op_iter_def
+};
+
+/* This structure is used in the operand iterator loops.  It contains the
+   items required to determine which operand is retrieved next.  During
+   optimization, this structure is scalarized, and any unused fields are
+   optimized away, resulting in little overhead.  */
+
+struct ssa_op_iter
+{
+  enum ssa_op_iter_type iter_type;
+  bool done;
+  int flags;
+  unsigned i;
+  unsigned numops;
+  use_optype_p uses;
+  gimple *stmt;
+};
+
+/* NOTE: Keep these in sync with doc/tree-ssa.texi.  */
+/* These flags are used to determine which operands are returned during
+   execution of the loop.  */
+#define SSA_OP_USE		0x01	/* Real USE operands.  */
+#define SSA_OP_DEF		0x02	/* Real DEF operands.  */
+#define SSA_OP_VUSE		0x04	/* VUSE operands.  */
+#define SSA_OP_VDEF		0x08	/* VDEF operands.  */
+/* These are commonly grouped operand flags.  */
+#define SSA_OP_VIRTUAL_USES	(SSA_OP_VUSE)
+#define SSA_OP_VIRTUAL_DEFS	(SSA_OP_VDEF)
+#define SSA_OP_ALL_VIRTUALS     (SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_DEFS)
+#define SSA_OP_ALL_USES		(SSA_OP_VIRTUAL_USES | SSA_OP_USE)
+#define SSA_OP_ALL_DEFS		(SSA_OP_VIRTUAL_DEFS | SSA_OP_DEF)
+#define SSA_OP_ALL_OPERANDS	(SSA_OP_ALL_USES | SSA_OP_ALL_DEFS)
+
+/* This macro executes a loop over the operands of STMT specified in FLAG,
+   returning each operand as a 'tree' in the variable TREEVAR.  ITER is an
+   ssa_op_iter structure used to control the loop.  */
+#define FOR_EACH_SSA_TREE_OPERAND(TREEVAR, STMT, ITER, FLAGS)	\
+  for (TREEVAR = op_iter_init_tree (&(ITER), STMT, FLAGS);	\
+       !op_iter_done (&(ITER));					\
+       (void) (TREEVAR = op_iter_next_tree (&(ITER))))
+
+/* This macro executes a loop over the operands of STMT specified in FLAG,
+   returning each operand as a 'use_operand_p' in the variable USEVAR.
+   ITER is an ssa_op_iter structure used to control the loop.  */
+#define FOR_EACH_SSA_USE_OPERAND(USEVAR, STMT, ITER, FLAGS)	\
+  for (USEVAR = op_iter_init_use (&(ITER), STMT, FLAGS);	\
+       !op_iter_done (&(ITER));					\
+       USEVAR = op_iter_next_use (&(ITER)))
+
+/* This macro executes a loop over the operands of STMT specified in FLAG,
+   returning each operand as a 'def_operand_p' in the variable DEFVAR.
+   ITER is an ssa_op_iter structure used to control the loop.  */
+#define FOR_EACH_SSA_DEF_OPERAND(DEFVAR, STMT, ITER, FLAGS)	\
+  for (DEFVAR = op_iter_init_def (&(ITER), STMT, FLAGS);	\
+       !op_iter_done (&(ITER));					\
+       DEFVAR = op_iter_next_def (&(ITER)))
+
+/* This macro will execute a loop over all the arguments of a PHI which
+   match FLAGS.   A use_operand_p is always returned via USEVAR.  FLAGS
+   can be either SSA_OP_USE or SSA_OP_VIRTUAL_USES or SSA_OP_ALL_USES.  */
+#define FOR_EACH_PHI_ARG(USEVAR, STMT, ITER, FLAGS)		\
+  for ((USEVAR) = op_iter_init_phiuse (&(ITER), STMT, FLAGS);	\
+       !op_iter_done (&(ITER));					\
+       (USEVAR) = op_iter_next_use (&(ITER)))
+
+
+/* This macro will execute a loop over a stmt, regardless of whether it is
+   a real stmt or a PHI node, looking at the USE nodes matching FLAGS.  */
+#define FOR_EACH_PHI_OR_STMT_USE(USEVAR, STMT, ITER, FLAGS)	\
+  for ((USEVAR) = (gimple_code (STMT) == GIMPLE_PHI 		\
+		   ? op_iter_init_phiuse (&(ITER),              \
+					  as_a <gphi *> (STMT), \
+					  FLAGS)		\
+		   : op_iter_init_use (&(ITER), STMT, FLAGS));	\
+       !op_iter_done (&(ITER));					\
+       (USEVAR) = op_iter_next_use (&(ITER)))
+
+/* This macro will execute a loop over a stmt, regardless of whether it is
+   a real stmt or a PHI node, looking at the DEF nodes matching FLAGS.  */
+#define FOR_EACH_PHI_OR_STMT_DEF(DEFVAR, STMT, ITER, FLAGS)	\
+  for ((DEFVAR) = (gimple_code (STMT) == GIMPLE_PHI 		\
+		   ? op_iter_init_phidef (&(ITER),		\
+					  as_a <gphi *> (STMT), \
+					  FLAGS)		\
+		   : op_iter_init_def (&(ITER), STMT, FLAGS));	\
+       !op_iter_done (&(ITER));					\
+       (DEFVAR) = op_iter_next_def (&(ITER)))
+
+/* This macro returns an operand in STMT as a tree if it is the ONLY
+   operand matching FLAGS.  If there are 0 or more than 1 operand matching
+   FLAGS, then NULL_TREE is returned.  */
+#define SINGLE_SSA_TREE_OPERAND(STMT, FLAGS)			\
+  single_ssa_tree_operand (STMT, FLAGS)
+
+/* This macro returns an operand in STMT as a use_operand_p if it is the ONLY
+   operand matching FLAGS.  If there are 0 or more than 1 operand matching
+   FLAGS, then NULL_USE_OPERAND_P is returned.  */
+#define SINGLE_SSA_USE_OPERAND(STMT, FLAGS)			\
+  single_ssa_use_operand (STMT, FLAGS)
+
+/* This macro returns an operand in STMT as a def_operand_p if it is the ONLY
+   operand matching FLAGS.  If there are 0 or more than 1 operand matching
+   FLAGS, then NULL_DEF_OPERAND_P is returned.  */
+#define SINGLE_SSA_DEF_OPERAND(STMT, FLAGS)			\
+  single_ssa_def_operand (STMT, FLAGS)
+
+/* This macro returns TRUE if there are no operands matching FLAGS in STMT.  */
+#define ZERO_SSA_OPERANDS(STMT, FLAGS) 	zero_ssa_operands (STMT, FLAGS)
+
+/* This macro counts the number of operands in STMT matching FLAGS.  */
+#define NUM_SSA_OPERANDS(STMT, FLAGS)	num_ssa_operands (STMT, FLAGS)
+
+
+/* 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));
+      if (linknode->use)
+        gcc_checking_assert (*(linknode->use) == def);
+      link_imm_use_to_list (linknode, root);
+    }
+}
+
+/* Set the value of a use pointed to 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, gimple *stmt)
+{
+  if (stmt)
+    link_imm_use (linknode, def);
+  else
+    link_imm_use (linknode, NULL);
+  linknode->loc.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_checking_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,
+		     gimple *stmt)
+{
+  if (stmt)
+    relink_imm_use (linknode, old);
+  else
+    link_imm_use (linknode, NULL);
+  linknode->loc.stmt = stmt;
+}
+
+
+/* Return true is IMM has reached the end of the immediate use list.  */
+static inline bool
+end_readonly_imm_use_p (const 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)
+{
+  imm->end_p = &(SSA_NAME_IMM_USE_NODE (var));
+  imm->imm_use = imm->end_p->next;
+  imm->iter_node.next = imm->imm_use->next;
+  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;
+
+  /* If this assertion fails, it indicates the 'next' pointer has changed
+     since 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.  */
+  if (flag_checking)
+    {
+      gcc_assert (imm->iter_node.next == old->next);
+      imm->iter_node.next = old->next->next;
+    }
+
+  imm->imm_use = old->next;
+  if (end_readonly_imm_use_p (imm))
+    return NULL_USE_OPERAND_P;
+  return imm->imm_use;
+}
+
+
+/* Return true if VAR has no nondebug uses.  */
+static inline bool
+has_zero_uses (const_tree var)
+{
+  const ssa_use_operand_t *const head = &(SSA_NAME_IMM_USE_NODE (var));
+  const ssa_use_operand_t *ptr;
+
+  for (ptr = head->next; ptr != head; ptr = ptr->next)
+    if (USE_STMT (ptr) && !is_gimple_debug (USE_STMT (ptr)))
+      return false;
+
+  return true;
+}
+
+/* Return true if VAR has a single nondebug use.  */
+static inline bool
+has_single_use (const_tree var)
+{
+  const ssa_use_operand_t *const head = &(SSA_NAME_IMM_USE_NODE (var));
+  const ssa_use_operand_t *ptr;
+  bool single = false;
+   
+  for (ptr = head->next; ptr != head; ptr = ptr->next)
+    if (USE_STMT(ptr) && !is_gimple_debug (USE_STMT (ptr)))
+      {
+	if (single)
+	  return false;
+	else 
+	  single = true;
+      }
+
+  return single;
+}
+    
+/* If VAR has only a single immediate nondebug use, return true, and
+   set USE_P and STMT to the use pointer and stmt of occurrence.  */
+static inline bool
+single_imm_use (const_tree var, use_operand_p *use_p, gimple **stmt)
+{
+  const ssa_use_operand_t *const ptr = &(SSA_NAME_IMM_USE_NODE (var));
+
+  /* If there aren't any uses whatsoever, we're done.  */
+  if (ptr == ptr->next)
+    {
+    return_false:
+      *use_p = NULL_USE_OPERAND_P;
+      *stmt = NULL;
+      return false;
+    }
+
+  /* If there's a single use, check that it's not a debug stmt.  */
+  if (ptr == ptr->next->next)
+    {
+      if (USE_STMT (ptr->next) && !is_gimple_debug (USE_STMT (ptr->next)))
+	{
+	  *use_p = ptr->next;
+	  *stmt = ptr->next->loc.stmt;
+	  return true;
+	}
+      else
+	goto return_false;
+    }
+
+  return single_imm_use_1 (ptr, use_p, stmt);
+}
+
+/* Return the number of nondebug immediate uses of VAR.  */
+static inline unsigned int
+num_imm_uses (const_tree var)
+{
+  const ssa_use_operand_t *const start = &(SSA_NAME_IMM_USE_NODE (var));
+  const ssa_use_operand_t *ptr;
+  unsigned int num = 0;
+
+  if (!MAY_HAVE_DEBUG_STMTS)
+    {
+      for (ptr = start->next; ptr != start; ptr = ptr->next)
+	if (USE_STMT (ptr))
+	  num++;
+    }
+  else
+    for (ptr = start->next; ptr != start; ptr = ptr->next)
+      if (USE_STMT (ptr) && !is_gimple_debug (USE_STMT (ptr)))
+	num++;
+
+  return num;
+}
+
+/*  -----------------------------------------------------------------------  */
+
+/* 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 (const 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;
+  gcc_checking_assert (ptr->iter_type == ssa_op_iter_use);
+  if (ptr->uses)
+    {
+      use_p = USE_OP_PTR (ptr->uses);
+      ptr->uses = ptr->uses->next;
+      return use_p;
+    }
+  if (ptr->i < ptr->numops)
+    {
+      return PHI_ARG_DEF_PTR (ptr->stmt, (ptr->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)
+{
+  gcc_checking_assert (ptr->iter_type == ssa_op_iter_def);
+  if (ptr->flags & SSA_OP_VDEF)
+    {
+      tree *p;
+      ptr->flags &= ~SSA_OP_VDEF;
+      p = gimple_vdef_ptr (ptr->stmt);
+      if (p && *p)
+	return p;
+    }
+  if (ptr->flags & SSA_OP_DEF)
+    {
+      while (ptr->i < ptr->numops)
+	{
+	  tree *val = gimple_op_ptr (ptr->stmt, ptr->i);
+	  ptr->i++;
+	  if (*val)
+	    {
+	      if (TREE_CODE (*val) == TREE_LIST)
+		val = &TREE_VALUE (*val);
+	      if (TREE_CODE (*val) == SSA_NAME
+		  || is_gimple_reg (*val))
+		return val;
+	    }
+	}
+      ptr->flags &= ~SSA_OP_DEF;
+    }
+
+  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;
+  gcc_checking_assert (ptr->iter_type == ssa_op_iter_tree);
+  if (ptr->uses)
+    {
+      val = USE_OP (ptr->uses);
+      ptr->uses = ptr->uses->next;
+      return val;
+    }
+  if (ptr->flags & SSA_OP_VDEF)
+    {
+      ptr->flags &= ~SSA_OP_VDEF;
+      if ((val = gimple_vdef (ptr->stmt)))
+	return val;
+    }
+  if (ptr->flags & SSA_OP_DEF)
+    {
+      while (ptr->i < ptr->numops)
+	{
+	  val = gimple_op (ptr->stmt, ptr->i);
+	  ptr->i++;
+	  if (val)
+	    {
+	      if (TREE_CODE (val) == TREE_LIST)
+		val = TREE_VALUE (val);
+	      if (TREE_CODE (val) == SSA_NAME
+		  || is_gimple_reg (val))
+		return val;
+	    }
+	}
+      ptr->flags &= ~SSA_OP_DEF;
+    }
+
+  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 uninitialized
+   components.  */
+
+static inline void
+clear_and_done_ssa_iter (ssa_op_iter *ptr)
+{
+  ptr->i = 0;
+  ptr->numops = 0;
+  ptr->uses = NULL;
+  ptr->iter_type = ssa_op_iter_none;
+  ptr->stmt = NULL;
+  ptr->done = true;
+  ptr->flags = 0;
+}
+
+/* Initialize the iterator PTR to the virtual defs in STMT.  */
+static inline void
+op_iter_init (ssa_op_iter *ptr, gimple *stmt, int flags)
+{
+  /* PHI nodes require a different iterator initialization path.  We
+     do not support iterating over virtual defs or uses without
+     iterating over defs or uses at the same time.  */
+  gcc_checking_assert (gimple_code (stmt) != GIMPLE_PHI
+		       && (!(flags & SSA_OP_VDEF) || (flags & SSA_OP_DEF))
+		       && (!(flags & SSA_OP_VUSE) || (flags & SSA_OP_USE)));
+  ptr->numops = 0;
+  if (flags & (SSA_OP_DEF | SSA_OP_VDEF))
+    {
+      switch (gimple_code (stmt))
+	{
+	  case GIMPLE_ASSIGN:
+	  case GIMPLE_CALL:
+	    ptr->numops = 1;
+	    break;
+	  case GIMPLE_ASM:
+	    ptr->numops = gimple_asm_noutputs (as_a <gasm *> (stmt));
+	    break;
+	  case GIMPLE_TRANSACTION:
+	    ptr->numops = 0;
+	    flags &= ~SSA_OP_DEF;
+	    break;
+	  default:
+	    ptr->numops = 0;
+	    flags &= ~(SSA_OP_DEF | SSA_OP_VDEF);
+	    break;
+	}
+    }
+  ptr->uses = (flags & (SSA_OP_USE|SSA_OP_VUSE)) ? gimple_use_ops (stmt) : NULL;
+  if (!(flags & SSA_OP_VUSE)
+      && ptr->uses
+      && gimple_vuse (stmt) != NULL_TREE)
+    ptr->uses = ptr->uses->next;
+  ptr->done = false;
+  ptr->i = 0;
+
+  ptr->stmt = stmt;
+  ptr->flags = flags;
+}
+
+/* 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, gimple *stmt, int flags)
+{
+  gcc_checking_assert ((flags & SSA_OP_ALL_DEFS) == 0
+		       && (flags & SSA_OP_USE));
+  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, gimple *stmt, int flags)
+{
+  gcc_checking_assert ((flags & SSA_OP_ALL_USES) == 0
+		       && (flags & SSA_OP_DEF));
+  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, gimple *stmt, int flags)
+{
+  op_iter_init (ptr, stmt, flags);
+  ptr->iter_type = ssa_op_iter_tree;
+  return op_iter_next_tree (ptr);
+}
+
+
+/* If there is a single operand in STMT matching FLAGS, return it.  Otherwise
+   return NULL.  */
+static inline tree
+single_ssa_tree_operand (gimple *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.  */
+static inline use_operand_p
+single_ssa_use_operand (gimple *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;
+}
+
+/* Return the single virtual use operand in STMT if present.  Otherwise
+   return NULL.  */
+static inline use_operand_p
+ssa_vuse_operand (gimple *stmt)
+{
+  if (! gimple_vuse (stmt))
+    return NULL_USE_OPERAND_P;
+  return USE_OP_PTR (gimple_use_ops (stmt));
+}
+
+
+/* If there is a single operand in STMT matching FLAGS, return it.  Otherwise
+   return NULL.  */
+static inline def_operand_p
+single_ssa_def_operand (gimple *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;
+}
+
+
+/* Return true if there are zero operands in STMT matching the type
+   given in FLAGS.  */
+static inline bool
+zero_ssa_operands (gimple *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 (gimple *stmt, int flags)
+{
+  ssa_op_iter iter;
+  tree t;
+  int num = 0;
+
+  gcc_checking_assert (gimple_code (stmt) != GIMPLE_PHI);
+  FOR_EACH_SSA_TREE_OPERAND (t, stmt, iter, flags)
+    num++;
+  return num;
+}
+
+/* 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 (gphi *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 SSA_OP_VIRTUAL_USES.  */
+static inline use_operand_p
+op_iter_init_phiuse (ssa_op_iter *ptr, gphi *phi, int flags)
+{
+  tree phi_def = gimple_phi_result (phi);
+  int comp;
+
+  clear_and_done_ssa_iter (ptr);
+  ptr->done = false;
+
+  gcc_checking_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->stmt = phi;
+  ptr->numops = gimple_phi_num_args (phi);
+  ptr->iter_type = ssa_op_iter_use;
+  ptr->flags = flags;
+  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, gphi *phi, int flags)
+{
+  tree phi_def = PHI_RESULT (phi);
+  int comp;
+
+  clear_and_done_ssa_iter (ptr);
+  ptr->done = false;
+
+  gcc_checking_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 have the operand type we care about,
+     we're done.  */
+  if ((flags & comp) == 0)
+    {
+      ptr->done = true;
+      return NULL_DEF_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 is IMM has reached the end of the immediate use stmt list.  */
+
+static inline bool
+end_imm_use_stmt_p (const imm_use_iterator *imm)
+{
+  return (imm->imm_use == imm->end_p);
+}
+
+/* Finished the traverse of an immediate use stmt list IMM by removing the
+   placeholder node from the list.  */
+
+static inline void
+end_imm_use_stmt_traverse (imm_use_iterator *imm)
+{
+  delink_imm_use (&(imm->iter_node));
+}
+
+/* Immediate use traversal of uses within a stmt require that all the
+   uses on a stmt be sequentially listed.  This routine is used to build up
+   this sequential list by adding USE_P to the end of the current list
+   currently delimited by HEAD and LAST_P.  The new LAST_P value is
+   returned.  */
+
+static inline use_operand_p
+move_use_after_head (use_operand_p use_p, use_operand_p head,
+		      use_operand_p last_p)
+{
+  gcc_checking_assert (USE_FROM_PTR (use_p) == USE_FROM_PTR (head));
+  /* Skip head when we find it.  */
+  if (use_p != head)
+    {
+      /* If use_p is already linked in after last_p, continue.  */
+      if (last_p->next == use_p)
+	last_p = use_p;
+      else
+	{
+	  /* Delink from current location, and link in at last_p.  */
+	  delink_imm_use (use_p);
+	  link_imm_use_to_list (use_p, last_p);
+	  last_p = use_p;
+	}
+    }
+  return last_p;
+}
+
+
+/* This routine will relink all uses with the same stmt as HEAD into the list
+   immediately following HEAD for iterator IMM.  */
+
+static inline void
+link_use_stmts_after (use_operand_p head, imm_use_iterator *imm)
+{
+  use_operand_p use_p;
+  use_operand_p last_p = head;
+  gimple *head_stmt = USE_STMT (head);
+  tree use = USE_FROM_PTR (head);
+  ssa_op_iter op_iter;
+  int flag;
+
+  /* Only look at virtual or real uses, depending on the type of HEAD.  */
+  flag = (is_gimple_reg (use) ? SSA_OP_USE : SSA_OP_VIRTUAL_USES);
+
+  if (gphi *phi = dyn_cast <gphi *> (head_stmt))
+    {
+      FOR_EACH_PHI_ARG (use_p, phi, op_iter, flag)
+	if (USE_FROM_PTR (use_p) == use)
+	  last_p = move_use_after_head (use_p, head, last_p);
+    }
+  else
+    {
+      if (flag == SSA_OP_USE)
+	{
+	  FOR_EACH_SSA_USE_OPERAND (use_p, head_stmt, op_iter, flag)
+	    if (USE_FROM_PTR (use_p) == use)
+	      last_p = move_use_after_head (use_p, head, last_p);
+	}
+      else if ((use_p = gimple_vuse_op (head_stmt)) != NULL_USE_OPERAND_P)
+	{
+	  if (USE_FROM_PTR (use_p) == use)
+	    last_p = move_use_after_head (use_p, head, last_p);
+	}
+    }
+  /* Link iter node in after last_p.  */
+  if (imm->iter_node.prev != NULL)
+    delink_imm_use (&imm->iter_node);
+  link_imm_use_to_list (&(imm->iter_node), last_p);
+}
+
+/* Initialize IMM to traverse over uses of VAR.  Return the first statement.  */
+static inline gimple *
+first_imm_use_stmt (imm_use_iterator *imm, tree var)
+{
+  imm->end_p = &(SSA_NAME_IMM_USE_NODE (var));
+  imm->imm_use = imm->end_p->next;
+  imm->next_imm_name = NULL_USE_OPERAND_P;
+
+  /* iter_node is used as a marker within the immediate use list to indicate
+     where the end of the current stmt's uses are.  Initialize it to NULL
+     stmt and use, which indicates a marker node.  */
+  imm->iter_node.prev = NULL_USE_OPERAND_P;
+  imm->iter_node.next = NULL_USE_OPERAND_P;
+  imm->iter_node.loc.stmt = NULL;
+  imm->iter_node.use = NULL;
+
+  if (end_imm_use_stmt_p (imm))
+    return NULL;
+
+  link_use_stmts_after (imm->imm_use, imm);
+
+  return USE_STMT (imm->imm_use);
+}
+
+/* Bump IMM to the next stmt which has a use of var.  */
+
+static inline gimple *
+next_imm_use_stmt (imm_use_iterator *imm)
+{
+  imm->imm_use = imm->iter_node.next;
+  if (end_imm_use_stmt_p (imm))
+    {
+      if (imm->iter_node.prev != NULL)
+	delink_imm_use (&imm->iter_node);
+      return NULL;
+    }
+
+  link_use_stmts_after (imm->imm_use, imm);
+  return USE_STMT (imm->imm_use);
+}
+
+/* This routine will return the first use on the stmt IMM currently refers
+   to.  */
+
+static inline use_operand_p
+first_imm_use_on_stmt (imm_use_iterator *imm)
+{
+  imm->next_imm_name = imm->imm_use->next;
+  return imm->imm_use;
+}
+
+/*  Return TRUE if the last use on the stmt IMM refers to has been visited.  */
+
+static inline bool
+end_imm_use_on_stmt_p (const imm_use_iterator *imm)
+{
+  return (imm->imm_use == &(imm->iter_node));
+}
+
+/* Bump to the next use on the stmt IMM refers to, return NULL if done.  */
+
+static inline use_operand_p
+next_imm_use_on_stmt (imm_use_iterator *imm)
+{
+  imm->imm_use = imm->next_imm_name;
+  if (end_imm_use_on_stmt_p (imm))
+    return NULL_USE_OPERAND_P;
+  else
+    {
+      imm->next_imm_name = imm->imm_use->next;
+      return imm->imm_use;
+    }
+}
+
+/* Delink all immediate_use information for STMT.  */
+static inline void
+delink_stmt_imm_use (gimple *stmt)
+{
+   ssa_op_iter iter;
+   use_operand_p use_p;
+
+   if (ssa_operands_active (cfun))
+     FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_ALL_USES)
+       delink_imm_use (use_p);
+}
+
+#endif /* GCC_TREE_SSA_ITERATORS_H */