Initial checkin of unmodified gcc-5666.3.tar.gz

This is the source to build gcc-4.2 for MacOSX

   gcc version 4.2.1 (Apple Inc. build 5666) (dot 3)

http://opensource.apple.com/tarballs/gcc/gcc-5666.3.tar.gz

Change-Id: I69540223f018e9d07f861fca04bd3833fc138f8b

1 files changed, 1576 insertions, 0 deletions

diff --git a/gcc-4.2.1-5666.3/gcc/tree-ssa-loop-im.c b/gcc-4.2.1-5666.3/gcc/tree-ssa-loop-im.c
new file mode 100644
index 000000000..43bfbbca8
--- /dev/null
+++ b/gcc-4.2.1-5666.3/gcc/tree-ssa-loop-im.c
@@ -0,0 +1,1576 @@
+/* Loop invariant motion.
+   Copyright (C) 2003, 2004, 2005 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 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.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "tree.h"
+#include "rtl.h"
+#include "tm_p.h"
+#include "hard-reg-set.h"
+#include "basic-block.h"
+#include "output.h"
+#include "diagnostic.h"
+#include "tree-flow.h"
+#include "tree-dump.h"
+#include "timevar.h"
+#include "cfgloop.h"
+#include "domwalk.h"
+#include "params.h"
+#include "tree-pass.h"
+#include "flags.h"
+#include "real.h"
+#include "hashtab.h"
+
+/* TODO:  Support for predicated code motion.  I.e.
+
+   while (1)
+     {
+       if (cond)
+	 {
+	   a = inv;
+	   something;
+	 }
+     }
+
+   Where COND and INV are is invariants, but evaluating INV may trap or be
+   invalid from some other reason if !COND.  This may be transformed to
+
+   if (cond)
+     a = inv;
+   while (1)
+     {
+       if (cond)
+	 something;
+     }  */
+
+/* A type for the list of statements that have to be moved in order to be able
+   to hoist an invariant computation.  */
+
+struct depend
+{
+  tree stmt;
+  struct depend *next;
+};
+
+/* The auxiliary data kept for each statement.  */
+
+struct lim_aux_data
+{
+  struct loop *max_loop;	/* The outermost loop in that the statement
+				   is invariant.  */
+
+  struct loop *tgt_loop;	/* The loop out of that we want to move the
+				   invariant.  */
+
+  struct loop *always_executed_in;
+				/* The outermost loop for that we are sure
+				   the statement is executed if the loop
+				   is entered.  */
+
+  bool sm_done;			/* True iff the store motion for a memory
+				   reference in the statement has already
+				   been executed.  */
+
+  unsigned cost;		/* Cost of the computation performed by the
+				   statement.  */
+
+  struct depend *depends;	/* List of statements that must be also hoisted
+				   out of the loop when this statement is
+				   hoisted; i.e. those that define the operands
+				   of the statement and are inside of the
+				   MAX_LOOP loop.  */
+};
+
+#define LIM_DATA(STMT) (TREE_CODE (STMT) == PHI_NODE \
+			? NULL \
+			: (struct lim_aux_data *) (stmt_ann (STMT)->common.aux))
+
+/* Description of a memory reference location for store motion.  */
+
+struct mem_ref_loc
+{
+  tree *ref;			/* The reference itself.  */
+  tree stmt;			/* The statement in that it occurs.  */
+  struct mem_ref_loc *next;	/* Next use in the chain.  */
+};
+
+/* Description of a memory reference for store motion.  */
+
+struct mem_ref
+{
+  tree mem;			/* The memory itself.  */
+  hashval_t hash;		/* Its hash value.  */
+  bool is_stored;		/* True if there is a store to the location
+				   in the loop.  */
+  struct mem_ref_loc *locs;	/* The locations where it is found.  */
+  bitmap vops;			/* Vops corresponding to this memory
+				   location.  */
+  struct mem_ref *next;		/* Next memory reference in the list.
+				   Memory references are stored in a hash
+				   table, but the hash function depends
+				   on values of pointers. Thus we cannot use
+				   htab_traverse, since then we would get
+				   miscompares during bootstrap (although the
+				   produced code would be correct).  */
+};
+
+/* Minimum cost of an expensive expression.  */
+#define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE))
+
+/* The outermost loop for that execution of the header guarantees that the
+   block will be executed.  */
+#define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux)
+
+/* Calls CBCK for each index in memory reference ADDR_P.  There are two
+   kinds situations handled; in each of these cases, the memory reference
+   and DATA are passed to the callback:
+   
+   Access to an array: ARRAY_{RANGE_}REF (base, index).  In this case we also
+   pass the pointer to the index to the callback.
+
+   Pointer dereference: INDIRECT_REF (addr).  In this case we also pass the
+   pointer to addr to the callback.
+   
+   If the callback returns false, the whole search stops and false is returned.
+   Otherwise the function returns true after traversing through the whole
+   reference *ADDR_P.  */
+
+bool
+for_each_index (tree *addr_p, bool (*cbck) (tree, tree *, void *), void *data)
+{
+  tree *nxt, *idx;
+
+  for (; ; addr_p = nxt)
+    {
+      switch (TREE_CODE (*addr_p))
+	{
+	case SSA_NAME:
+	  return cbck (*addr_p, addr_p, data);
+
+	case MISALIGNED_INDIRECT_REF:
+	case ALIGN_INDIRECT_REF:
+	case INDIRECT_REF:
+	  nxt = &TREE_OPERAND (*addr_p, 0);
+	  return cbck (*addr_p, nxt, data);
+
+	case BIT_FIELD_REF:
+	/* APPLE LOCAL begin 4175845 */
+	/* VIEW_CONVERT_EXPR removed */
+	/* APPLE LOCAL end 4175845 */
+	case REALPART_EXPR:
+	case IMAGPART_EXPR:
+	  nxt = &TREE_OPERAND (*addr_p, 0);
+	  break;
+
+	/* APPLE LOCAL begin 4175845 */
+	case VIEW_CONVERT_EXPR:
+	  nxt = &TREE_OPERAND (*addr_p, 0);
+	  /* Copying struct as integers, followed by copy prop,
+	     can produce a constant here.  Likely other things
+	     can too; in any event it is a legitimate thing to
+	     happen and should be handled.  */
+	  if (TREE_CODE (*nxt) == INTEGER_CST)
+	    return true;
+	  break;
+	/* APPLE LOCAL end 4175845 */
+
+	case COMPONENT_REF:
+	  /* If the component has varying offset, it behaves like index
+	     as well.  */
+	  idx = &TREE_OPERAND (*addr_p, 2);
+	  if (*idx
+	      && !cbck (*addr_p, idx, data))
+	    return false;
+
+	  nxt = &TREE_OPERAND (*addr_p, 0);
+	  break;
+
+	case ARRAY_REF:
+	case ARRAY_RANGE_REF:
+	  nxt = &TREE_OPERAND (*addr_p, 0);
+	  if (!cbck (*addr_p, &TREE_OPERAND (*addr_p, 1), data))
+	    return false;
+	  break;
+
+	case VAR_DECL:
+	case PARM_DECL:
+	case STRING_CST:
+	case RESULT_DECL:
+	case VECTOR_CST:
+	case COMPLEX_CST:
+	case INTEGER_CST:
+	case REAL_CST:
+	  return true;
+
+	case TARGET_MEM_REF:
+	  idx = &TMR_BASE (*addr_p);
+	  if (*idx
+	      && !cbck (*addr_p, idx, data))
+	    return false;
+	  idx = &TMR_INDEX (*addr_p);
+	  if (*idx
+	      && !cbck (*addr_p, idx, data))
+	    return false;
+	  return true;
+
+	default:
+    	  gcc_unreachable ();
+	}
+    }
+}
+
+/* If it is possible to hoist the statement STMT unconditionally,
+   returns MOVE_POSSIBLE.
+   If it is possible to hoist the statement STMT, but we must avoid making
+   it executed if it would not be executed in the original program (e.g.
+   because it may trap), return MOVE_PRESERVE_EXECUTION.
+   Otherwise return MOVE_IMPOSSIBLE.  */
+
+enum move_pos
+movement_possibility (tree stmt)
+{
+  tree lhs, rhs;
+
+  if (flag_unswitch_loops
+      && TREE_CODE (stmt) == COND_EXPR)
+    {
+      /* If we perform unswitching, force the operands of the invariant
+	 condition to be moved out of the loop.  */
+      return MOVE_POSSIBLE;
+    }
+
+  if (TREE_CODE (stmt) != MODIFY_EXPR)
+    return MOVE_IMPOSSIBLE;
+
+  if (stmt_ends_bb_p (stmt))
+    return MOVE_IMPOSSIBLE;
+
+  if (stmt_ann (stmt)->has_volatile_ops)
+    return MOVE_IMPOSSIBLE;
+
+  lhs = TREE_OPERAND (stmt, 0);
+  if (TREE_CODE (lhs) == SSA_NAME
+      && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs))
+    return MOVE_IMPOSSIBLE;
+
+  rhs = TREE_OPERAND (stmt, 1);
+
+  if (TREE_SIDE_EFFECTS (rhs))
+    return MOVE_IMPOSSIBLE;
+
+  if (TREE_CODE (lhs) != SSA_NAME
+      || tree_could_trap_p (rhs))
+    return MOVE_PRESERVE_EXECUTION;
+
+  if (get_call_expr_in (stmt))
+    {
+      /* While pure or const call is guaranteed to have no side effects, we
+	 cannot move it arbitrarily.  Consider code like
+
+	 char *s = something ();
+
+	 while (1)
+	   {
+	     if (s)
+	       t = strlen (s);
+	     else
+	       t = 0;
+	   }
+
+	 Here the strlen call cannot be moved out of the loop, even though
+	 s is invariant.  In addition to possibly creating a call with
+	 invalid arguments, moving out a function call that is not executed
+	 may cause performance regressions in case the call is costly and
+	 not executed at all.  */
+      return MOVE_PRESERVE_EXECUTION;
+    }
+  return MOVE_POSSIBLE;
+}
+
+/* Suppose that operand DEF is used inside the LOOP.  Returns the outermost
+   loop to that we could move the expression using DEF if it did not have
+   other operands, i.e. the outermost loop enclosing LOOP in that the value
+   of DEF is invariant.  */
+
+static struct loop *
+outermost_invariant_loop (tree def, struct loop *loop)
+{
+  tree def_stmt;
+  basic_block def_bb;
+  struct loop *max_loop;
+
+  if (TREE_CODE (def) != SSA_NAME)
+    return superloop_at_depth (loop, 1);
+
+  def_stmt = SSA_NAME_DEF_STMT (def);
+  def_bb = bb_for_stmt (def_stmt);
+  if (!def_bb)
+    return superloop_at_depth (loop, 1);
+
+  max_loop = find_common_loop (loop, def_bb->loop_father);
+
+  if (LIM_DATA (def_stmt) && LIM_DATA (def_stmt)->max_loop)
+    max_loop = find_common_loop (max_loop,
+				 LIM_DATA (def_stmt)->max_loop->outer);
+  if (max_loop == loop)
+    return NULL;
+  max_loop = superloop_at_depth (loop, max_loop->depth + 1);
+
+  return max_loop;
+}
+
+/* Returns the outermost superloop of LOOP in that the expression EXPR is
+   invariant.  */
+
+static struct loop *
+outermost_invariant_loop_expr (tree expr, struct loop *loop)
+{
+  enum tree_code_class class = TREE_CODE_CLASS (TREE_CODE (expr));
+  unsigned i, nops;
+  struct loop *max_loop = superloop_at_depth (loop, 1), *aloop;
+
+  if (TREE_CODE (expr) == SSA_NAME
+      || TREE_CODE (expr) == INTEGER_CST
+      || is_gimple_min_invariant (expr))
+    return outermost_invariant_loop (expr, loop);
+
+  if (class != tcc_unary
+      && class != tcc_binary
+      && class != tcc_expression
+      && class != tcc_comparison)
+    return NULL;
+
+  nops = TREE_CODE_LENGTH (TREE_CODE (expr));
+  for (i = 0; i < nops; i++)
+    {
+      aloop = outermost_invariant_loop_expr (TREE_OPERAND (expr, i), loop);
+      if (!aloop)
+	return NULL;
+
+      if (flow_loop_nested_p (max_loop, aloop))
+	max_loop = aloop;
+    }
+
+  return max_loop;
+}
+
+/* DATA is a structure containing information associated with a statement
+   inside LOOP.  DEF is one of the operands of this statement.
+   
+   Find the outermost loop enclosing LOOP in that value of DEF is invariant
+   and record this in DATA->max_loop field.  If DEF itself is defined inside
+   this loop as well (i.e. we need to hoist it out of the loop if we want
+   to hoist the statement represented by DATA), record the statement in that
+   DEF is defined to the DATA->depends list.  Additionally if ADD_COST is true,
+   add the cost of the computation of DEF to the DATA->cost.
+   
+   If DEF is not invariant in LOOP, return false.  Otherwise return TRUE.  */
+
+static bool
+add_dependency (tree def, struct lim_aux_data *data, struct loop *loop,
+		bool add_cost)
+{
+  tree def_stmt = SSA_NAME_DEF_STMT (def);
+  basic_block def_bb = bb_for_stmt (def_stmt);
+  struct loop *max_loop;
+  struct depend *dep;
+
+  if (!def_bb)
+    return true;
+
+  max_loop = outermost_invariant_loop (def, loop);
+  if (!max_loop)
+    return false;
+
+  if (flow_loop_nested_p (data->max_loop, max_loop))
+    data->max_loop = max_loop;
+
+  if (!LIM_DATA (def_stmt))
+    return true;
+
+  if (add_cost
+      /* Only add the cost if the statement defining DEF is inside LOOP,
+	 i.e. if it is likely that by moving the invariants dependent
+	 on it, we will be able to avoid creating a new register for
+	 it (since it will be only used in these dependent invariants).  */
+      && def_bb->loop_father == loop)
+    data->cost += LIM_DATA (def_stmt)->cost;
+
+  dep = XNEW (struct depend);
+  dep->stmt = def_stmt;
+  dep->next = data->depends;
+  data->depends = dep;
+
+  return true;
+}
+
+/* Returns an estimate for a cost of statement STMT.  TODO -- the values here
+   are just ad-hoc constants.  The estimates should be based on target-specific
+   values.  */
+
+static unsigned
+stmt_cost (tree stmt)
+{
+  tree rhs;
+  unsigned cost = 1;
+
+  /* Always try to create possibilities for unswitching.  */
+  if (TREE_CODE (stmt) == COND_EXPR)
+    return LIM_EXPENSIVE;
+
+  rhs = TREE_OPERAND (stmt, 1);
+
+  /* Hoisting memory references out should almost surely be a win.  */
+  if (stmt_references_memory_p (stmt))
+    cost += 20;
+
+  switch (TREE_CODE (rhs))
+    {
+    case CALL_EXPR:
+      /* We should be hoisting calls if possible.  */
+
+      /* Unless the call is a builtin_constant_p; this always folds to a
+	 constant, so moving it is useless.  */
+      rhs = get_callee_fndecl (rhs);
+      if (DECL_BUILT_IN_CLASS (rhs) == BUILT_IN_NORMAL
+	  && DECL_FUNCTION_CODE (rhs) == BUILT_IN_CONSTANT_P)
+	return 0;
+
+      cost += 20;
+      break;
+
+    case MULT_EXPR:
+    case TRUNC_DIV_EXPR:
+    case CEIL_DIV_EXPR:
+    case FLOOR_DIV_EXPR:
+    case ROUND_DIV_EXPR:
+    case EXACT_DIV_EXPR:
+    case CEIL_MOD_EXPR:
+    case FLOOR_MOD_EXPR:
+    case ROUND_MOD_EXPR:
+    case TRUNC_MOD_EXPR:
+    case RDIV_EXPR:
+      /* Division and multiplication are usually expensive.  */
+      cost += 20;
+      break;
+
+    default:
+      break;
+    }
+
+  return cost;
+}
+
+/* Determine the outermost loop to that it is possible to hoist a statement
+   STMT and store it to LIM_DATA (STMT)->max_loop.  To do this we determine
+   the outermost loop in that the value computed by STMT is invariant.
+   If MUST_PRESERVE_EXEC is true, additionally choose such a loop that
+   we preserve the fact whether STMT is executed.  It also fills other related
+   information to LIM_DATA (STMT).
+   
+   The function returns false if STMT cannot be hoisted outside of the loop it
+   is defined in, and true otherwise.  */
+
+static bool
+determine_max_movement (tree stmt, bool must_preserve_exec)
+{
+  basic_block bb = bb_for_stmt (stmt);
+  struct loop *loop = bb->loop_father;
+  struct loop *level;
+  struct lim_aux_data *lim_data = LIM_DATA (stmt);
+  tree val;
+  ssa_op_iter iter;
+  
+  if (must_preserve_exec)
+    level = ALWAYS_EXECUTED_IN (bb);
+  else
+    level = superloop_at_depth (loop, 1);
+  lim_data->max_loop = level;
+
+  FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE)
+    if (!add_dependency (val, lim_data, loop, true))
+      return false;
+
+  FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
+    if (!add_dependency (val, lim_data, loop, false))
+      return false;
+
+  lim_data->cost += stmt_cost (stmt);
+
+  return true;
+}
+
+/* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL,
+   and that one of the operands of this statement is computed by STMT.
+   Ensure that STMT (together with all the statements that define its
+   operands) is hoisted at least out of the loop LEVEL.  */
+
+static void
+set_level (tree stmt, struct loop *orig_loop, struct loop *level)
+{
+  struct loop *stmt_loop = bb_for_stmt (stmt)->loop_father;
+  struct depend *dep;
+
+  stmt_loop = find_common_loop (orig_loop, stmt_loop);
+  if (LIM_DATA (stmt) && LIM_DATA (stmt)->tgt_loop)
+    stmt_loop = find_common_loop (stmt_loop,
+				  LIM_DATA (stmt)->tgt_loop->outer);
+  if (flow_loop_nested_p (stmt_loop, level))
+    return;
+
+  gcc_assert (LIM_DATA (stmt));
+  gcc_assert (level == LIM_DATA (stmt)->max_loop
+	      || flow_loop_nested_p (LIM_DATA (stmt)->max_loop, level));
+
+  LIM_DATA (stmt)->tgt_loop = level;
+  for (dep = LIM_DATA (stmt)->depends; dep; dep = dep->next)
+    set_level (dep->stmt, orig_loop, level);
+}
+
+/* Determines an outermost loop from that we want to hoist the statement STMT.
+   For now we chose the outermost possible loop.  TODO -- use profiling
+   information to set it more sanely.  */
+
+static void
+set_profitable_level (tree stmt)
+{
+  set_level (stmt, bb_for_stmt (stmt)->loop_father, LIM_DATA (stmt)->max_loop);
+}
+
+/* Returns true if STMT is not a pure call.  */
+
+static bool
+nonpure_call_p (tree stmt)
+{
+  tree call = get_call_expr_in (stmt);
+
+  if (!call)
+    return false;
+
+  return TREE_SIDE_EFFECTS (call) != 0;
+}
+
+/* Releases the memory occupied by DATA.  */
+
+static void
+free_lim_aux_data (struct lim_aux_data *data)
+{
+  struct depend *dep, *next;
+
+  for (dep = data->depends; dep; dep = next)
+    {
+      next = dep->next;
+      free (dep);
+    }
+  free (data);
+}
+
+/* Determine the outermost loops in that statements in basic block BB are
+   invariant, and record them to the LIM_DATA associated with the statements.
+   Callback for walk_dominator_tree.  */
+
+static void
+determine_invariantness_stmt (struct dom_walk_data *dw_data ATTRIBUTE_UNUSED,
+			      basic_block bb)
+{
+  enum move_pos pos;
+  block_stmt_iterator bsi;
+  tree stmt, rhs;
+  bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL;
+  struct loop *outermost = ALWAYS_EXECUTED_IN (bb);
+
+  if (!bb->loop_father->outer)
+    return;
+
+  if (dump_file && (dump_flags & TDF_DETAILS))
+    fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n",
+	     bb->index, bb->loop_father->num, bb->loop_father->depth);
+
+  for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+    {
+      stmt = bsi_stmt (bsi);
+
+      pos = movement_possibility (stmt);
+      if (pos == MOVE_IMPOSSIBLE)
+	{
+	  if (nonpure_call_p (stmt))
+	    {
+	      maybe_never = true;
+	      outermost = NULL;
+	    }
+	  continue;
+	}
+
+      /* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal
+	 to be hoisted out of loop, saving expensive divide.  */
+      if (pos == MOVE_POSSIBLE
+	  && (rhs = TREE_OPERAND (stmt, 1)) != NULL
+	  && TREE_CODE (rhs) == RDIV_EXPR
+	  && flag_unsafe_math_optimizations
+	  && !flag_trapping_math
+	  && outermost_invariant_loop_expr (TREE_OPERAND (rhs, 1),
+					    loop_containing_stmt (stmt)) != NULL
+	  && outermost_invariant_loop_expr (rhs,
+					    loop_containing_stmt (stmt)) == NULL)
+	{
+	  tree lhs, stmt1, stmt2, var, name;
+
+	  lhs = TREE_OPERAND (stmt, 0);
+
+	  /* stmt must be MODIFY_EXPR.  */
+	  var = create_tmp_var (TREE_TYPE (rhs), "reciptmp");
+	  add_referenced_var (var);
+
+	  stmt1 = build2 (MODIFY_EXPR, void_type_node, var,
+			  build2 (RDIV_EXPR, TREE_TYPE (rhs),
+				  build_real (TREE_TYPE (rhs), dconst1),
+				  TREE_OPERAND (rhs, 1)));
+	  name = make_ssa_name (var, stmt1);
+	  TREE_OPERAND (stmt1, 0) = name;
+	  stmt2 = build2 (MODIFY_EXPR, void_type_node, lhs,
+			  build2 (MULT_EXPR, TREE_TYPE (rhs),
+				  name, TREE_OPERAND (rhs, 0)));
+
+	  /* Replace division stmt with reciprocal and multiply stmts.
+	     The multiply stmt is not invariant, so update iterator
+	     and avoid rescanning.  */
+	  bsi_replace (&bsi, stmt1, true);
+	  bsi_insert_after (&bsi, stmt2, BSI_NEW_STMT);
+	  SSA_NAME_DEF_STMT (lhs) = stmt2;
+
+	  /* Continue processing with invariant reciprocal statement.  */
+	  stmt = stmt1;
+	}
+
+      stmt_ann (stmt)->common.aux = xcalloc (1, sizeof (struct lim_aux_data));
+      LIM_DATA (stmt)->always_executed_in = outermost;
+
+      if (maybe_never && pos == MOVE_PRESERVE_EXECUTION)
+	continue;
+
+      if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION))
+	{
+	  LIM_DATA (stmt)->max_loop = NULL;
+	  continue;
+	}
+
+      if (dump_file && (dump_flags & TDF_DETAILS))
+	{
+	  print_generic_stmt_indented (dump_file, stmt, 0, 2);
+	  fprintf (dump_file, "  invariant up to level %d, cost %d.\n\n",
+		   LIM_DATA (stmt)->max_loop->depth,
+		   LIM_DATA (stmt)->cost);
+	}
+
+      if (LIM_DATA (stmt)->cost >= LIM_EXPENSIVE)
+	set_profitable_level (stmt);
+    }
+}
+
+/* For each statement determines the outermost loop in that it is invariant,
+   statements on whose motion it depends and the cost of the computation.
+   This information is stored to the LIM_DATA structure associated with
+   each statement.  */
+
+static void
+determine_invariantness (void)
+{
+  struct dom_walk_data walk_data;
+
+  memset (&walk_data, 0, sizeof (struct dom_walk_data));
+  walk_data.before_dom_children_before_stmts = determine_invariantness_stmt;
+
+  init_walk_dominator_tree (&walk_data);
+  walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
+  fini_walk_dominator_tree (&walk_data);
+}
+
+/* Commits edge insertions and updates loop structures.  */
+
+void
+loop_commit_inserts (void)
+{
+  unsigned old_last_basic_block, i;
+  basic_block bb;
+
+  old_last_basic_block = last_basic_block;
+  bsi_commit_edge_inserts ();
+  for (i = old_last_basic_block; i < (unsigned) last_basic_block; i++)
+    {
+      bb = BASIC_BLOCK (i);
+      add_bb_to_loop (bb,
+		      find_common_loop (single_pred (bb)->loop_father,
+					single_succ (bb)->loop_father));
+    }
+}
+
+/* Hoist the statements in basic block BB out of the loops prescribed by
+   data stored in LIM_DATA structures associated with each statement.  Callback
+   for walk_dominator_tree.  */
+
+static void
+move_computations_stmt (struct dom_walk_data *dw_data ATTRIBUTE_UNUSED,
+			basic_block bb)
+{
+  struct loop *level;
+  block_stmt_iterator bsi;
+  tree stmt;
+  unsigned cost = 0;
+
+  if (!bb->loop_father->outer)
+    return;
+
+  for (bsi = bsi_start (bb); !bsi_end_p (bsi); )
+    {
+      stmt = bsi_stmt (bsi);
+
+      if (!LIM_DATA (stmt))
+	{
+	  bsi_next (&bsi);
+	  continue;
+	}
+
+      cost = LIM_DATA (stmt)->cost;
+      level = LIM_DATA (stmt)->tgt_loop;
+      free_lim_aux_data (LIM_DATA (stmt));
+      stmt_ann (stmt)->common.aux = NULL;
+
+      if (!level)
+	{
+	  bsi_next (&bsi);
+	  continue;
+	}
+
+      /* We do not really want to move conditionals out of the loop; we just
+	 placed it here to force its operands to be moved if necessary.  */
+      if (TREE_CODE (stmt) == COND_EXPR)
+	continue;
+
+      if (dump_file && (dump_flags & TDF_DETAILS))
+	{
+	  fprintf (dump_file, "Moving statement\n");
+	  print_generic_stmt (dump_file, stmt, 0);
+	  fprintf (dump_file, "(cost %u) out of loop %d.\n\n",
+		   cost, level->num);
+	}
+      bsi_insert_on_edge (loop_preheader_edge (level), stmt);
+      bsi_remove (&bsi, false);
+    }
+}
+
+/* Hoist the statements out of the loops prescribed by data stored in
+   LIM_DATA structures associated with each statement.*/
+
+static void
+move_computations (void)
+{
+  struct dom_walk_data walk_data;
+
+  memset (&walk_data, 0, sizeof (struct dom_walk_data));
+  walk_data.before_dom_children_before_stmts = move_computations_stmt;
+
+  init_walk_dominator_tree (&walk_data);
+  walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
+  fini_walk_dominator_tree (&walk_data);
+
+  loop_commit_inserts ();
+  if (need_ssa_update_p ())
+    rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
+}
+
+/* Checks whether the statement defining variable *INDEX can be hoisted
+   out of the loop passed in DATA.  Callback for for_each_index.  */
+
+static bool
+may_move_till (tree ref, tree *index, void *data)
+{
+  struct loop *loop = data, *max_loop;
+
+  /* If REF is an array reference, check also that the step and the lower
+     bound is invariant in LOOP.  */
+  if (TREE_CODE (ref) == ARRAY_REF)
+    {
+      tree step = array_ref_element_size (ref);
+      tree lbound = array_ref_low_bound (ref);
+
+      max_loop = outermost_invariant_loop_expr (step, loop);
+      if (!max_loop)
+	return false;
+
+      max_loop = outermost_invariant_loop_expr (lbound, loop);
+      if (!max_loop)
+	return false;
+    }
+
+  max_loop = outermost_invariant_loop (*index, loop);
+  if (!max_loop)
+    return false;
+
+  return true;
+}
+
+/* Forces statements defining (invariant) SSA names in expression EXPR to be
+   moved out of the LOOP.  ORIG_LOOP is the loop in that EXPR is used.  */
+
+static void
+force_move_till_expr (tree expr, struct loop *orig_loop, struct loop *loop)
+{
+  enum tree_code_class class = TREE_CODE_CLASS (TREE_CODE (expr));
+  unsigned i, nops;
+
+  if (TREE_CODE (expr) == SSA_NAME)
+    {
+      tree stmt = SSA_NAME_DEF_STMT (expr);
+      if (IS_EMPTY_STMT (stmt))
+	return;
+
+      set_level (stmt, orig_loop, loop);
+      return;
+    }
+
+  if (class != tcc_unary
+      && class != tcc_binary
+      && class != tcc_expression
+      && class != tcc_comparison)
+    return;
+
+  nops = TREE_CODE_LENGTH (TREE_CODE (expr));
+  for (i = 0; i < nops; i++)
+    force_move_till_expr (TREE_OPERAND (expr, i), orig_loop, loop);
+}
+
+/* Forces statement defining invariants in REF (and *INDEX) to be moved out of
+   the LOOP.  The reference REF is used in the loop ORIG_LOOP.  Callback for
+   for_each_index.  */
+
+struct fmt_data
+{
+  struct loop *loop;
+  struct loop *orig_loop;
+};
+
+static bool
+force_move_till (tree ref, tree *index, void *data)
+{
+  tree stmt;
+  struct fmt_data *fmt_data = data;
+
+  if (TREE_CODE (ref) == ARRAY_REF)
+    {
+      tree step = array_ref_element_size (ref);
+      tree lbound = array_ref_low_bound (ref);
+
+      force_move_till_expr (step, fmt_data->orig_loop, fmt_data->loop);
+      force_move_till_expr (lbound, fmt_data->orig_loop, fmt_data->loop);
+    }
+
+  if (TREE_CODE (*index) != SSA_NAME)
+    return true;
+
+  stmt = SSA_NAME_DEF_STMT (*index);
+  if (IS_EMPTY_STMT (stmt))
+    return true;
+
+  set_level (stmt, fmt_data->orig_loop, fmt_data->loop);
+
+  return true;
+}
+
+/* Records memory reference location *REF to the list MEM_REFS.  The reference
+   occurs in statement STMT.  */
+
+static void
+record_mem_ref_loc (struct mem_ref_loc **mem_refs, tree stmt, tree *ref)
+{
+  struct mem_ref_loc *aref = XNEW (struct mem_ref_loc);
+
+  aref->stmt = stmt;
+  aref->ref = ref;
+
+  aref->next = *mem_refs;
+  *mem_refs = aref;
+}
+
+/* Releases list of memory reference locations MEM_REFS.  */
+
+static void
+free_mem_ref_locs (struct mem_ref_loc *mem_refs)
+{
+  struct mem_ref_loc *act;
+
+  while (mem_refs)
+    {
+      act = mem_refs;
+      mem_refs = mem_refs->next;
+      free (act);
+    }
+}
+
+/* Rewrites memory references in list MEM_REFS by variable TMP_VAR.  */
+
+static void
+rewrite_mem_refs (tree tmp_var, struct mem_ref_loc *mem_refs)
+{
+  tree var;
+  ssa_op_iter iter;
+
+  for (; mem_refs; mem_refs = mem_refs->next)
+    {
+      FOR_EACH_SSA_TREE_OPERAND (var, mem_refs->stmt, iter, SSA_OP_ALL_VIRTUALS)
+	mark_sym_for_renaming (SSA_NAME_VAR (var));
+
+      *mem_refs->ref = tmp_var;
+      update_stmt (mem_refs->stmt);
+    }
+}
+
+/* The name and the length of the currently generated variable
+   for lsm.  */
+#define MAX_LSM_NAME_LENGTH 40
+static char lsm_tmp_name[MAX_LSM_NAME_LENGTH + 1];
+static int lsm_tmp_name_length;
+
+/* Adds S to lsm_tmp_name.  */
+
+static void
+lsm_tmp_name_add (const char *s)
+{
+  int l = strlen (s) + lsm_tmp_name_length;
+  if (l > MAX_LSM_NAME_LENGTH)
+    return;
+
+  strcpy (lsm_tmp_name + lsm_tmp_name_length, s);
+  lsm_tmp_name_length = l;
+}
+
+/* Stores the name for temporary variable that replaces REF to
+   lsm_tmp_name.  */
+
+static void
+gen_lsm_tmp_name (tree ref)
+{
+  const char *name;
+
+  switch (TREE_CODE (ref))
+    {
+    case MISALIGNED_INDIRECT_REF:
+    case ALIGN_INDIRECT_REF:
+    case INDIRECT_REF:
+      gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
+      lsm_tmp_name_add ("_");
+      break;
+
+    case BIT_FIELD_REF:
+    case VIEW_CONVERT_EXPR:
+    case ARRAY_RANGE_REF:
+      gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
+      break;
+
+    case REALPART_EXPR:
+      gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
+      lsm_tmp_name_add ("_RE");
+      break;
+      
+    case IMAGPART_EXPR:
+      gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
+      lsm_tmp_name_add ("_IM");
+      break;
+
+    case COMPONENT_REF:
+      gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
+      lsm_tmp_name_add ("_");
+      name = get_name (TREE_OPERAND (ref, 1));
+      if (!name)
+	name = "F";
+      lsm_tmp_name_add ("_");
+      lsm_tmp_name_add (name);
+
+    case ARRAY_REF:
+      gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
+      lsm_tmp_name_add ("_I");
+      break;
+
+    case SSA_NAME:
+      ref = SSA_NAME_VAR (ref);
+      /* Fallthru.  */
+
+    case VAR_DECL:
+    case PARM_DECL:
+      name = get_name (ref);
+      if (!name)
+	name = "D";
+      lsm_tmp_name_add (name);
+      break;
+
+    case STRING_CST:
+      lsm_tmp_name_add ("S");
+      break;
+
+    case RESULT_DECL:
+      lsm_tmp_name_add ("R");
+      break;
+
+    default:
+      gcc_unreachable ();
+    }
+}
+
+/* Determines name for temporary variable that replaces REF.
+   The name is accumulated into the lsm_tmp_name variable.  */
+
+static char *
+get_lsm_tmp_name (tree ref)
+{
+  lsm_tmp_name_length = 0;
+  gen_lsm_tmp_name (ref);
+  lsm_tmp_name_add ("_lsm");
+  return lsm_tmp_name;
+}
+
+/* Records request for store motion of memory reference REF from LOOP.
+   MEM_REFS is the list of occurrences of the reference REF inside LOOP;
+   these references are rewritten by a new temporary variable.
+   Exits from the LOOP are stored in EXITS, there are N_EXITS of them.
+   The initialization of the temporary variable is put to the preheader
+   of the loop, and assignments to the reference from the temporary variable
+   are emitted to exits.  */
+
+static void
+schedule_sm (struct loop *loop, edge *exits, unsigned n_exits, tree ref,
+	     struct mem_ref_loc *mem_refs)
+{
+  struct mem_ref_loc *aref;
+  tree tmp_var;
+  unsigned i;
+  tree load, store;
+  struct fmt_data fmt_data;
+
+  if (dump_file && (dump_flags & TDF_DETAILS))
+    {
+      fprintf (dump_file, "Executing store motion of ");
+      print_generic_expr (dump_file, ref, 0);
+      fprintf (dump_file, " from loop %d\n", loop->num);
+    }
+
+  tmp_var = make_rename_temp (TREE_TYPE (ref),
+			      get_lsm_tmp_name (ref));
+
+  fmt_data.loop = loop;
+  fmt_data.orig_loop = loop;
+  for_each_index (&ref, force_move_till, &fmt_data);
+
+  rewrite_mem_refs (tmp_var, mem_refs);
+  for (aref = mem_refs; aref; aref = aref->next)
+    if (LIM_DATA (aref->stmt))
+      LIM_DATA (aref->stmt)->sm_done = true;
+
+  /* Emit the load & stores.  */
+  load = build2 (MODIFY_EXPR, void_type_node, tmp_var, ref);
+  get_stmt_ann (load)->common.aux = xcalloc (1, sizeof (struct lim_aux_data));
+  LIM_DATA (load)->max_loop = loop;
+  LIM_DATA (load)->tgt_loop = loop;
+
+  /* Put this into the latch, so that we are sure it will be processed after
+     all dependencies.  */
+  bsi_insert_on_edge (loop_latch_edge (loop), load);
+
+  for (i = 0; i < n_exits; i++)
+    {
+      store = build2 (MODIFY_EXPR, void_type_node,
+		      unshare_expr (ref), tmp_var);
+      bsi_insert_on_edge (exits[i], store);
+    }
+}
+
+/* Check whether memory reference REF can be hoisted out of the LOOP.  If this
+   is true, prepare the statements that load the value of the memory reference
+   to a temporary variable in the loop preheader, store it back on the loop
+   exits, and replace all the references inside LOOP by this temporary variable.
+   LOOP has N_EXITS stored in EXITS.  CLOBBERED_VOPS is the bitmap of virtual
+   operands that are clobbered by a call or accessed through multiple references
+   in loop.  */
+
+static void
+determine_lsm_ref (struct loop *loop, edge *exits, unsigned n_exits,
+		   bitmap clobbered_vops, struct mem_ref *ref)
+{
+  struct mem_ref_loc *aref;
+  struct loop *must_exec;
+
+  /* In case the memory is not stored to, there is nothing for SM to do.  */
+  if (!ref->is_stored)
+    return;
+
+  /* If the reference is aliased with any different ref, or killed by call
+     in function, then fail.  */
+  if (bitmap_intersect_p (ref->vops, clobbered_vops))
+    return;
+
+  if (tree_could_trap_p (ref->mem))
+    {
+      /* If the memory access is unsafe (i.e. it might trap), ensure that some
+	 of the statements in that it occurs is always executed when the loop
+	 is entered.  This way we know that by moving the load from the
+	 reference out of the loop we will not cause the error that would not
+	 occur otherwise.
+
+	 TODO -- in fact we would like to check for anticipability of the
+	 reference, i.e. that on each path from loop entry to loop exit at
+	 least one of the statements containing the memory reference is
+	 executed.  */
+
+      for (aref = ref->locs; aref; aref = aref->next)
+	{
+	  if (!LIM_DATA (aref->stmt))
+	    continue;
+
+	  must_exec = LIM_DATA (aref->stmt)->always_executed_in;
+	  if (!must_exec)
+	    continue;
+
+	  if (must_exec == loop
+	      || flow_loop_nested_p (must_exec, loop))
+	    break;
+	}
+
+      if (!aref)
+	return;
+    }
+
+  schedule_sm (loop, exits, n_exits, ref->mem, ref->locs);
+}
+
+/* Hoists memory references MEM_REFS out of LOOP.  CLOBBERED_VOPS is the list
+   of vops clobbered by call in loop or accessed by multiple memory references.
+   EXITS is the list of N_EXITS exit edges of the LOOP.  */
+
+static void
+hoist_memory_references (struct loop *loop, struct mem_ref *mem_refs,
+			 bitmap clobbered_vops, edge *exits, unsigned n_exits)
+{
+  struct mem_ref *ref;
+
+  for (ref = mem_refs; ref; ref = ref->next)
+    determine_lsm_ref (loop, exits, n_exits, clobbered_vops, ref);
+}
+
+/* Checks whether LOOP (with N_EXITS exits stored in EXITS array) is suitable
+   for a store motion optimization (i.e. whether we can insert statement
+   on its exits).  */
+
+static bool
+loop_suitable_for_sm (struct loop *loop ATTRIBUTE_UNUSED, edge *exits,
+		      unsigned n_exits)
+{
+  unsigned i;
+
+  for (i = 0; i < n_exits; i++)
+    if (exits[i]->flags & EDGE_ABNORMAL)
+      return false;
+
+  return true;
+}
+
+/* A hash function for struct mem_ref object OBJ.  */
+
+static hashval_t
+memref_hash (const void *obj)
+{
+  const struct mem_ref *mem = obj;
+
+  return mem->hash;
+}
+
+/* An equality function for struct mem_ref object OBJ1 with
+   memory reference OBJ2.  */
+
+static int
+memref_eq (const void *obj1, const void *obj2)
+{
+  const struct mem_ref *mem1 = obj1;
+
+  return operand_equal_p (mem1->mem, (tree) obj2, 0);
+}
+
+/* Gathers memory references in statement STMT in LOOP, storing the
+   information about them in MEM_REFS hash table.  Note vops accessed through
+   unrecognized statements in CLOBBERED_VOPS.  The newly created references
+   are also stored to MEM_REF_LIST.  */
+
+static void
+gather_mem_refs_stmt (struct loop *loop, htab_t mem_refs,
+		      bitmap clobbered_vops, tree stmt,
+		      struct mem_ref **mem_ref_list)
+{
+  tree *lhs, *rhs, *mem = NULL;
+  hashval_t hash;
+  PTR *slot;
+  struct mem_ref *ref = NULL;
+  ssa_op_iter oi;
+  tree vname;
+  bool is_stored;
+
+  if (ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
+    return;
+
+  /* Recognize MEM = (SSA_NAME | invariant) and SSA_NAME = MEM patterns.  */
+  if (TREE_CODE (stmt) != MODIFY_EXPR)
+    goto fail;
+
+  lhs = &TREE_OPERAND (stmt, 0);
+  rhs = &TREE_OPERAND (stmt, 1);
+
+  if (TREE_CODE (*lhs) == SSA_NAME)
+    {
+      if (!is_gimple_addressable (*rhs))
+	goto fail;
+
+      mem = rhs;
+      is_stored = false;
+    }
+  else if (TREE_CODE (*rhs) == SSA_NAME
+	   || is_gimple_min_invariant (*rhs))
+    {
+      mem = lhs;
+      is_stored = true;
+    }
+  else
+    goto fail;
+
+  /* If we cannot create an SSA name for the result, give up.  */
+  if (!is_gimple_reg_type (TREE_TYPE (*mem))
+      || TREE_THIS_VOLATILE (*mem))
+    goto fail;
+
+  /* If we cannot move the reference out of the loop, fail.  */
+  if (!for_each_index (mem, may_move_till, loop))
+    goto fail;
+
+  hash = iterative_hash_expr (*mem, 0);
+  slot = htab_find_slot_with_hash (mem_refs, *mem, hash, INSERT);
+
+  if (*slot)
+    ref = *slot;
+  else
+    {
+      ref = XNEW (struct mem_ref);
+      ref->mem = *mem;
+      ref->hash = hash;
+      ref->locs = NULL;
+      ref->is_stored = false;
+      ref->vops = BITMAP_ALLOC (NULL);
+      ref->next = *mem_ref_list;
+      *mem_ref_list = ref;
+      *slot = ref;
+    }
+  ref->is_stored |= is_stored;
+
+  FOR_EACH_SSA_TREE_OPERAND (vname, stmt, oi,
+			     SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
+    bitmap_set_bit (ref->vops, DECL_UID (SSA_NAME_VAR (vname)));
+  record_mem_ref_loc (&ref->locs, stmt, mem);
+  return;
+
+fail:
+  FOR_EACH_SSA_TREE_OPERAND (vname, stmt, oi,
+			     SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
+    bitmap_set_bit (clobbered_vops, DECL_UID (SSA_NAME_VAR (vname)));
+}
+
+/* Gathers memory references in LOOP.  Notes vops accessed through unrecognized
+   statements in CLOBBERED_VOPS.  The list of the references found by
+   the function is returned.  */
+
+static struct mem_ref *
+gather_mem_refs (struct loop *loop, bitmap clobbered_vops)
+{
+  basic_block *body = get_loop_body (loop);
+  block_stmt_iterator bsi;
+  unsigned i;
+  struct mem_ref *mem_ref_list = NULL;
+  htab_t mem_refs = htab_create (100, memref_hash, memref_eq, NULL);
+
+  for (i = 0; i < loop->num_nodes; i++)
+    {
+      for (bsi = bsi_start (body[i]); !bsi_end_p (bsi); bsi_next (&bsi))
+	gather_mem_refs_stmt (loop, mem_refs, clobbered_vops, bsi_stmt (bsi),
+			      &mem_ref_list);
+    }
+
+  free (body);
+
+  htab_delete (mem_refs);
+  return mem_ref_list;
+}
+
+/* Finds the vops accessed by more than one of the memory references described
+   in MEM_REFS and marks them in CLOBBERED_VOPS.  */
+
+static void
+find_more_ref_vops (struct mem_ref *mem_refs, bitmap clobbered_vops)
+{
+  bitmap_head tmp, all_vops;
+  struct mem_ref *ref;
+
+  bitmap_initialize (&tmp, &bitmap_default_obstack);
+  bitmap_initialize (&all_vops, &bitmap_default_obstack);
+
+  for (ref = mem_refs; ref; ref = ref->next)
+    {
+      /* The vops that are already in all_vops are accessed by more than
+	 one memory reference.  */
+      bitmap_and (&tmp, &all_vops, ref->vops);
+      bitmap_ior_into (clobbered_vops, &tmp);
+      bitmap_clear (&tmp);
+
+      bitmap_ior_into (&all_vops, ref->vops);
+    }
+
+  bitmap_clear (&all_vops);
+}
+
+/* Releases the memory occupied by REF.  */
+
+static void
+free_mem_ref (struct mem_ref *ref)
+{
+  free_mem_ref_locs (ref->locs);
+  BITMAP_FREE (ref->vops);
+  free (ref);
+}
+
+/* Releases the memory occupied by REFS.  */
+
+static void
+free_mem_refs (struct mem_ref *refs)
+{
+  struct mem_ref *ref, *next;
+
+  for (ref = refs; ref; ref = next)
+    {
+      next = ref->next;
+      free_mem_ref (ref);
+    }
+}
+
+/* Try to perform store motion for all memory references modified inside
+   LOOP.  */
+
+static void
+determine_lsm_loop (struct loop *loop)
+{
+  unsigned n_exits;
+  edge *exits = get_loop_exit_edges (loop, &n_exits);
+  bitmap clobbered_vops;
+  struct mem_ref *mem_refs;
+
+  if (!loop_suitable_for_sm (loop, exits, n_exits))
+    {
+      free (exits);
+      return;
+    }
+
+  /* Find the memory references in LOOP.  */
+  clobbered_vops = BITMAP_ALLOC (NULL);
+  mem_refs = gather_mem_refs (loop, clobbered_vops);
+
+  /* Find the vops that are used for more than one reference.  */
+  find_more_ref_vops (mem_refs, clobbered_vops);
+
+  /* Hoist all suitable memory references.  */
+  hoist_memory_references (loop, mem_refs, clobbered_vops, exits, n_exits);
+
+  free_mem_refs (mem_refs);
+  free (exits);
+  BITMAP_FREE (clobbered_vops);
+}
+
+/* Try to perform store motion for all memory references modified inside
+   any of LOOPS.  */
+
+static void
+determine_lsm (struct loops *loops)
+{
+  struct loop *loop;
+
+  if (!loops->tree_root->inner)
+    return;
+
+  /* Pass the loops from the outermost and perform the store motion as
+     suitable.  */
+
+  loop = loops->tree_root->inner;
+  while (1)
+    {
+      determine_lsm_loop (loop);
+
+      if (loop->inner)
+	{
+	  loop = loop->inner;
+	  continue;
+	}
+      while (!loop->next)
+	{
+	  loop = loop->outer;
+	  if (loop == loops->tree_root)
+	    {
+	      loop_commit_inserts ();
+	      return;
+	    }
+	}
+      loop = loop->next;
+    }
+}
+
+/* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e.
+   for each such basic block bb records the outermost loop for that execution
+   of its header implies execution of bb.  CONTAINS_CALL is the bitmap of
+   blocks that contain a nonpure call.  */
+
+static void
+fill_always_executed_in (struct loop *loop, sbitmap contains_call)
+{
+  basic_block bb = NULL, *bbs, last = NULL;
+  unsigned i;
+  edge e;
+  struct loop *inn_loop = loop;
+
+  if (!loop->header->aux)
+    {
+      bbs = get_loop_body_in_dom_order (loop);
+
+      for (i = 0; i < loop->num_nodes; i++)
+	{
+	  edge_iterator ei;
+	  bb = bbs[i];
+
+	  if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb))
+	    last = bb;
+
+	  if (TEST_BIT (contains_call, bb->index))
+	    break;
+
+	  FOR_EACH_EDGE (e, ei, bb->succs)
+	    if (!flow_bb_inside_loop_p (loop, e->dest))
+	      break;
+	  if (e)
+	    break;
+
+	  /* A loop might be infinite (TODO use simple loop analysis
+	     to disprove this if possible).  */
+	  if (bb->flags & BB_IRREDUCIBLE_LOOP)
+	    break;
+
+	  if (!flow_bb_inside_loop_p (inn_loop, bb))
+	    break;
+
+	  if (bb->loop_father->header == bb)
+	    {
+	      if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb))
+		break;
+
+	      /* In a loop that is always entered we may proceed anyway.
+		 But record that we entered it and stop once we leave it.  */
+	      inn_loop = bb->loop_father;
+	    }
+	}
+
+      while (1)
+	{
+	  last->aux = loop;
+	  if (last == loop->header)
+	    break;
+	  last = get_immediate_dominator (CDI_DOMINATORS, last);
+	}
+
+      free (bbs);
+    }
+
+  for (loop = loop->inner; loop; loop = loop->next)
+    fill_always_executed_in (loop, contains_call);
+}
+
+/* Compute the global information needed by the loop invariant motion pass.
+   LOOPS is the loop tree.  */
+
+static void
+tree_ssa_lim_initialize (struct loops *loops)
+{
+  sbitmap contains_call = sbitmap_alloc (last_basic_block);
+  block_stmt_iterator bsi;
+  struct loop *loop;
+  basic_block bb;
+
+  sbitmap_zero (contains_call);
+  FOR_EACH_BB (bb)
+    {
+      for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+	{
+	  if (nonpure_call_p (bsi_stmt (bsi)))
+	    break;
+	}
+
+      if (!bsi_end_p (bsi))
+	SET_BIT (contains_call, bb->index);
+    }
+
+  for (loop = loops->tree_root->inner; loop; loop = loop->next)
+    fill_always_executed_in (loop, contains_call);
+
+  sbitmap_free (contains_call);
+}
+
+/* Cleans up after the invariant motion pass.  */
+
+static void
+tree_ssa_lim_finalize (void)
+{
+  basic_block bb;
+
+  FOR_EACH_BB (bb)
+    {
+      bb->aux = NULL;
+    }
+}
+
+/* Moves invariants from LOOPS.  Only "expensive" invariants are moved out --
+   i.e. those that are likely to be win regardless of the register pressure.  */
+
+void
+tree_ssa_lim (struct loops *loops)
+{
+  tree_ssa_lim_initialize (loops);
+
+  /* For each statement determine the outermost loop in that it is
+     invariant and cost for computing the invariant.  */
+  determine_invariantness ();
+
+  /* For each memory reference determine whether it is possible to hoist it
+     out of the loop.  Force the necessary invariants to be moved out of the
+     loops as well.  */
+  determine_lsm (loops);
+
+  /* Move the expressions that are expensive enough.  */
+  move_computations ();
+
+  tree_ssa_lim_finalize ();
+}