Initial checkin of GCC 4.9.0 from trunk (r208799).

Change-Id: I48a3c08bb98542aa215912a75f03c0890e497dba

1 files changed, 1171 insertions, 0 deletions

diff --git a/gcc-4.9/gcc/ggc-common.c b/gcc-4.9/gcc/ggc-common.c
new file mode 100644
index 000000000..97c9b87fc
--- /dev/null
+++ b/gcc-4.9/gcc/ggc-common.c
@@ -0,0 +1,1171 @@
+/* Simple garbage collection for the GNU compiler.
+   Copyright (C) 1999-2014 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+/* Generic garbage collection (GC) functions and data, not specific to
+   any particular GC implementation.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "hash-table.h"
+#include "ggc.h"
+#include "ggc-internal.h"
+#include "diagnostic-core.h"
+#include "params.h"
+#include "hosthooks.h"
+#include "hosthooks-def.h"
+#include "plugin.h"
+#include "vec.h"
+#include "timevar.h"
+
+/* When set, ggc_collect will do collection.  */
+bool ggc_force_collect;
+
+/* When true, protect the contents of the identifier hash table.  */
+bool ggc_protect_identifiers = true;
+
+/* Statistics about the allocation.  */
+static ggc_statistics *ggc_stats;
+
+struct traversal_state;
+
+static int ggc_htab_delete (void **, void *);
+static int compare_ptr_data (const void *, const void *);
+static void relocate_ptrs (void *, void *);
+static void write_pch_globals (const struct ggc_root_tab * const *tab,
+			       struct traversal_state *state);
+
+/* Maintain global roots that are preserved during GC.  */
+
+/* Process a slot of an htab by deleting it if it has not been marked.  */
+
+static int
+ggc_htab_delete (void **slot, void *info)
+{
+  const struct ggc_cache_tab *r = (const struct ggc_cache_tab *) info;
+
+  if (! (*r->marked_p) (*slot))
+    htab_clear_slot (*r->base, slot);
+  else
+    (*r->cb) (*slot);
+
+  return 1;
+}
+
+
+/* This extra vector of dynamically registered root_tab-s is used by
+   ggc_mark_roots and gives the ability to dynamically add new GGC root
+   tables, for instance from some plugins; this vector is on the heap
+   since it is used by GGC internally.  */
+typedef const struct ggc_root_tab *const_ggc_root_tab_t;
+static vec<const_ggc_root_tab_t> extra_root_vec;
+
+/* Dynamically register a new GGC root table RT. This is useful for
+   plugins. */
+
+void
+ggc_register_root_tab (const struct ggc_root_tab* rt)
+{
+  if (rt)
+    extra_root_vec.safe_push (rt);
+}
+
+/* This extra vector of dynamically registered cache_tab-s is used by
+   ggc_mark_roots and gives the ability to dynamically add new GGC cache
+   tables, for instance from some plugins; this vector is on the heap
+   since it is used by GGC internally.  */
+typedef const struct ggc_cache_tab *const_ggc_cache_tab_t;
+static vec<const_ggc_cache_tab_t> extra_cache_vec;
+
+/* Dynamically register a new GGC cache table CT. This is useful for
+   plugins. */
+
+void
+ggc_register_cache_tab (const struct ggc_cache_tab* ct)
+{
+  if (ct)
+    extra_cache_vec.safe_push (ct);
+}
+
+/* Scan a hash table that has objects which are to be deleted if they are not
+   already marked.  */
+
+static void
+ggc_scan_cache_tab (const_ggc_cache_tab_t ctp)
+{
+  const struct ggc_cache_tab *cti;
+
+  for (cti = ctp; cti->base != NULL; cti++)
+    if (*cti->base)
+      {
+        ggc_set_mark (*cti->base);
+        htab_traverse_noresize (*cti->base, ggc_htab_delete,
+                                CONST_CAST (void *, (const void *)cti));
+        ggc_set_mark ((*cti->base)->entries);
+      }
+}
+
+/* Mark all the roots in the table RT.  */
+
+static void
+ggc_mark_root_tab (const_ggc_root_tab_t rt)
+{
+  size_t i;
+
+  for ( ; rt->base != NULL; rt++)
+    for (i = 0; i < rt->nelt; i++)
+      (*rt->cb) (*(void **) ((char *)rt->base + rt->stride * i));
+}
+
+/* Iterate through all registered roots and mark each element.  */
+
+void
+ggc_mark_roots (void)
+{
+  const struct ggc_root_tab *const *rt;
+  const_ggc_root_tab_t rtp, rti;
+  const struct ggc_cache_tab *const *ct;
+  const_ggc_cache_tab_t ctp;
+  size_t i;
+
+  for (rt = gt_ggc_deletable_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      memset (rti->base, 0, rti->stride);
+
+  for (rt = gt_ggc_rtab; *rt; rt++)
+    ggc_mark_root_tab (*rt);
+
+  FOR_EACH_VEC_ELT (extra_root_vec, i, rtp)
+    ggc_mark_root_tab (rtp);
+
+  if (ggc_protect_identifiers)
+    ggc_mark_stringpool ();
+
+  /* Now scan all hash tables that have objects which are to be deleted if
+     they are not already marked.  */
+  for (ct = gt_ggc_cache_rtab; *ct; ct++)
+    ggc_scan_cache_tab (*ct);
+
+  FOR_EACH_VEC_ELT (extra_cache_vec, i, ctp)
+    ggc_scan_cache_tab (ctp);
+
+  if (! ggc_protect_identifiers)
+    ggc_purge_stringpool ();
+
+  /* Some plugins may call ggc_set_mark from here.  */
+  invoke_plugin_callbacks (PLUGIN_GGC_MARKING, NULL);
+}
+
+/* Allocate a block of memory, then clear it.  */
+void *
+ggc_internal_cleared_alloc_stat (size_t size MEM_STAT_DECL)
+{
+  void *buf = ggc_internal_alloc_stat (size PASS_MEM_STAT);
+  memset (buf, 0, size);
+  return buf;
+}
+
+/* Resize a block of memory, possibly re-allocating it.  */
+void *
+ggc_realloc_stat (void *x, size_t size MEM_STAT_DECL)
+{
+  void *r;
+  size_t old_size;
+
+  if (x == NULL)
+    return ggc_internal_alloc_stat (size PASS_MEM_STAT);
+
+  old_size = ggc_get_size (x);
+
+  if (size <= old_size)
+    {
+      /* Mark the unwanted memory as unaccessible.  We also need to make
+	 the "new" size accessible, since ggc_get_size returns the size of
+	 the pool, not the size of the individually allocated object, the
+	 size which was previously made accessible.  Unfortunately, we
+	 don't know that previously allocated size.  Without that
+	 knowledge we have to lose some initialization-tracking for the
+	 old parts of the object.  An alternative is to mark the whole
+	 old_size as reachable, but that would lose tracking of writes
+	 after the end of the object (by small offsets).  Discard the
+	 handle to avoid handle leak.  */
+      VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS ((char *) x + size,
+						    old_size - size));
+      VALGRIND_DISCARD (VALGRIND_MAKE_MEM_DEFINED (x, size));
+      return x;
+    }
+
+  r = ggc_internal_alloc_stat (size PASS_MEM_STAT);
+
+  /* Since ggc_get_size returns the size of the pool, not the size of the
+     individually allocated object, we'd access parts of the old object
+     that were marked invalid with the memcpy below.  We lose a bit of the
+     initialization-tracking since some of it may be uninitialized.  */
+  VALGRIND_DISCARD (VALGRIND_MAKE_MEM_DEFINED (x, old_size));
+
+  memcpy (r, x, old_size);
+
+  /* The old object is not supposed to be used anymore.  */
+  ggc_free (x);
+
+  return r;
+}
+
+void *
+ggc_cleared_alloc_htab_ignore_args (size_t c ATTRIBUTE_UNUSED,
+				    size_t n ATTRIBUTE_UNUSED)
+{
+  gcc_assert (c * n == sizeof (struct htab));
+  return ggc_alloc_cleared_htab ();
+}
+
+/* TODO: once we actually use type information in GGC, create a new tag
+   gt_gcc_ptr_array and use it for pointer arrays.  */
+void *
+ggc_cleared_alloc_ptr_array_two_args (size_t c, size_t n)
+{
+  gcc_assert (sizeof (PTR *) == n);
+  return ggc_internal_cleared_vec_alloc (sizeof (PTR *), c);
+}
+
+/* These are for splay_tree_new_ggc.  */
+void *
+ggc_splay_alloc (int sz, void *nl)
+{
+  gcc_assert (!nl);
+  return ggc_internal_alloc (sz);
+}
+
+void
+ggc_splay_dont_free (void * x ATTRIBUTE_UNUSED, void *nl)
+{
+  gcc_assert (!nl);
+}
+
+/* Print statistics that are independent of the collector in use.  */
+#define SCALE(x) ((unsigned long) ((x) < 1024*10 \
+		  ? (x) \
+		  : ((x) < 1024*1024*10 \
+		     ? (x) / 1024 \
+		     : (x) / (1024*1024))))
+#define LABEL(x) ((x) < 1024*10 ? ' ' : ((x) < 1024*1024*10 ? 'k' : 'M'))
+
+void
+ggc_print_common_statistics (FILE *stream ATTRIBUTE_UNUSED,
+			     ggc_statistics *stats)
+{
+  /* Set the pointer so that during collection we will actually gather
+     the statistics.  */
+  ggc_stats = stats;
+
+  /* Then do one collection to fill in the statistics.  */
+  ggc_collect ();
+
+  /* At present, we don't really gather any interesting statistics.  */
+
+  /* Don't gather statistics any more.  */
+  ggc_stats = NULL;
+}
+
+/* Functions for saving and restoring GCable memory to disk.  */
+
+struct ptr_data
+{
+  void *obj;
+  void *note_ptr_cookie;
+  gt_note_pointers note_ptr_fn;
+  gt_handle_reorder reorder_fn;
+  size_t size;
+  void *new_addr;
+};
+
+#define POINTER_HASH(x) (hashval_t)((intptr_t)x >> 3)
+
+/* Helper for hashing saving_htab.  */
+
+struct saving_hasher : typed_free_remove <ptr_data>
+{
+  typedef ptr_data value_type;
+  typedef void compare_type;
+  static inline hashval_t hash (const value_type *);
+  static inline bool equal (const value_type *, const compare_type *);
+};
+
+inline hashval_t
+saving_hasher::hash (const value_type *p)
+{
+  return POINTER_HASH (p->obj);
+}
+
+inline bool
+saving_hasher::equal (const value_type *p1, const compare_type *p2)
+{
+  return p1->obj == p2;
+}
+
+static hash_table <saving_hasher> saving_htab;
+
+/* Register an object in the hash table.  */
+
+int
+gt_pch_note_object (void *obj, void *note_ptr_cookie,
+		    gt_note_pointers note_ptr_fn)
+{
+  struct ptr_data **slot;
+
+  if (obj == NULL || obj == (void *) 1)
+    return 0;
+
+  slot = (struct ptr_data **)
+    saving_htab.find_slot_with_hash (obj, POINTER_HASH (obj), INSERT);
+  if (*slot != NULL)
+    {
+      gcc_assert ((*slot)->note_ptr_fn == note_ptr_fn
+		  && (*slot)->note_ptr_cookie == note_ptr_cookie);
+      return 0;
+    }
+
+  *slot = XCNEW (struct ptr_data);
+  (*slot)->obj = obj;
+  (*slot)->note_ptr_fn = note_ptr_fn;
+  (*slot)->note_ptr_cookie = note_ptr_cookie;
+  if (note_ptr_fn == gt_pch_p_S)
+    (*slot)->size = strlen ((const char *)obj) + 1;
+  else
+    (*slot)->size = ggc_get_size (obj);
+  return 1;
+}
+
+/* Register an object in the hash table.  */
+
+void
+gt_pch_note_reorder (void *obj, void *note_ptr_cookie,
+		     gt_handle_reorder reorder_fn)
+{
+  struct ptr_data *data;
+
+  if (obj == NULL || obj == (void *) 1)
+    return;
+
+  data = (struct ptr_data *)
+    saving_htab.find_with_hash (obj, POINTER_HASH (obj));
+  gcc_assert (data && data->note_ptr_cookie == note_ptr_cookie);
+
+  data->reorder_fn = reorder_fn;
+}
+
+/* Handy state for the traversal functions.  */
+
+struct traversal_state
+{
+  FILE *f;
+  struct ggc_pch_data *d;
+  size_t count;
+  struct ptr_data **ptrs;
+  size_t ptrs_i;
+};
+
+/* Callbacks for htab_traverse.  */
+
+int
+ggc_call_count (ptr_data **slot, traversal_state *state)
+{
+  struct ptr_data *d = *slot;
+
+  ggc_pch_count_object (state->d, d->obj, d->size,
+			d->note_ptr_fn == gt_pch_p_S);
+  state->count++;
+  return 1;
+}
+
+int
+ggc_call_alloc (ptr_data **slot, traversal_state *state)
+{
+  struct ptr_data *d = *slot;
+
+  d->new_addr = ggc_pch_alloc_object (state->d, d->obj, d->size,
+				      d->note_ptr_fn == gt_pch_p_S);
+  state->ptrs[state->ptrs_i++] = d;
+  return 1;
+}
+
+/* Callback for qsort.  */
+
+static int
+compare_ptr_data (const void *p1_p, const void *p2_p)
+{
+  const struct ptr_data *const p1 = *(const struct ptr_data *const *)p1_p;
+  const struct ptr_data *const p2 = *(const struct ptr_data *const *)p2_p;
+  return (((size_t)p1->new_addr > (size_t)p2->new_addr)
+	  - ((size_t)p1->new_addr < (size_t)p2->new_addr));
+}
+
+/* Callbacks for note_ptr_fn.  */
+
+static void
+relocate_ptrs (void *ptr_p, void *state_p)
+{
+  void **ptr = (void **)ptr_p;
+  struct traversal_state *state ATTRIBUTE_UNUSED
+    = (struct traversal_state *)state_p;
+  struct ptr_data *result;
+
+  if (*ptr == NULL || *ptr == (void *)1)
+    return;
+
+  result = (struct ptr_data *)
+    saving_htab.find_with_hash (*ptr, POINTER_HASH (*ptr));
+  gcc_assert (result);
+  *ptr = result->new_addr;
+}
+
+/* Write out, after relocation, the pointers in TAB.  */
+static void
+write_pch_globals (const struct ggc_root_tab * const *tab,
+		   struct traversal_state *state)
+{
+  const struct ggc_root_tab *const *rt;
+  const struct ggc_root_tab *rti;
+  size_t i;
+
+  for (rt = tab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      for (i = 0; i < rti->nelt; i++)
+	{
+	  void *ptr = *(void **)((char *)rti->base + rti->stride * i);
+	  struct ptr_data *new_ptr;
+	  if (ptr == NULL || ptr == (void *)1)
+	    {
+	      if (fwrite (&ptr, sizeof (void *), 1, state->f)
+		  != 1)
+		fatal_error ("can%'t write PCH file: %m");
+	    }
+	  else
+	    {
+	      new_ptr = (struct ptr_data *)
+		saving_htab.find_with_hash (ptr, POINTER_HASH (ptr));
+	      if (fwrite (&new_ptr->new_addr, sizeof (void *), 1, state->f)
+		  != 1)
+		fatal_error ("can%'t write PCH file: %m");
+	    }
+	}
+}
+
+/* Hold the information we need to mmap the file back in.  */
+
+struct mmap_info
+{
+  size_t offset;
+  size_t size;
+  void *preferred_base;
+};
+
+/* Write out the state of the compiler to F.  */
+
+void
+gt_pch_save (FILE *f)
+{
+  const struct ggc_root_tab *const *rt;
+  const struct ggc_root_tab *rti;
+  size_t i;
+  struct traversal_state state;
+  char *this_object = NULL;
+  size_t this_object_size = 0;
+  struct mmap_info mmi;
+  const size_t mmap_offset_alignment = host_hooks.gt_pch_alloc_granularity ();
+
+  gt_pch_save_stringpool ();
+
+  timevar_push (TV_PCH_PTR_REALLOC);
+  saving_htab.create (50000);
+
+  for (rt = gt_ggc_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      for (i = 0; i < rti->nelt; i++)
+	(*rti->pchw)(*(void **)((char *)rti->base + rti->stride * i));
+
+  for (rt = gt_pch_cache_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      for (i = 0; i < rti->nelt; i++)
+	(*rti->pchw)(*(void **)((char *)rti->base + rti->stride * i));
+
+  /* Prepare the objects for writing, determine addresses and such.  */
+  state.f = f;
+  state.d = init_ggc_pch ();
+  state.count = 0;
+  saving_htab.traverse <traversal_state *, ggc_call_count> (&state);
+
+  mmi.size = ggc_pch_total_size (state.d);
+
+  /* Try to arrange things so that no relocation is necessary, but
+     don't try very hard.  On most platforms, this will always work,
+     and on the rest it's a lot of work to do better.
+     (The extra work goes in HOST_HOOKS_GT_PCH_GET_ADDRESS and
+     HOST_HOOKS_GT_PCH_USE_ADDRESS.)  */
+  mmi.preferred_base = host_hooks.gt_pch_get_address (mmi.size, fileno (f));
+
+  ggc_pch_this_base (state.d, mmi.preferred_base);
+
+  state.ptrs = XNEWVEC (struct ptr_data *, state.count);
+  state.ptrs_i = 0;
+
+  saving_htab.traverse <traversal_state *, ggc_call_alloc> (&state);
+  timevar_pop (TV_PCH_PTR_REALLOC);
+
+  timevar_push (TV_PCH_PTR_SORT);
+  qsort (state.ptrs, state.count, sizeof (*state.ptrs), compare_ptr_data);
+  timevar_pop (TV_PCH_PTR_SORT);
+
+  /* Write out all the scalar variables.  */
+  for (rt = gt_pch_scalar_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      if (fwrite (rti->base, rti->stride, 1, f) != 1)
+	fatal_error ("can%'t write PCH file: %m");
+
+  /* Write out all the global pointers, after translation.  */
+  write_pch_globals (gt_ggc_rtab, &state);
+  write_pch_globals (gt_pch_cache_rtab, &state);
+
+  /* Pad the PCH file so that the mmapped area starts on an allocation
+     granularity (usually page) boundary.  */
+  {
+    long o;
+    o = ftell (state.f) + sizeof (mmi);
+    if (o == -1)
+      fatal_error ("can%'t get position in PCH file: %m");
+    mmi.offset = mmap_offset_alignment - o % mmap_offset_alignment;
+    if (mmi.offset == mmap_offset_alignment)
+      mmi.offset = 0;
+    mmi.offset += o;
+  }
+  if (fwrite (&mmi, sizeof (mmi), 1, state.f) != 1)
+    fatal_error ("can%'t write PCH file: %m");
+  if (mmi.offset != 0
+      && fseek (state.f, mmi.offset, SEEK_SET) != 0)
+    fatal_error ("can%'t write padding to PCH file: %m");
+
+  ggc_pch_prepare_write (state.d, state.f);
+
+#if defined ENABLE_VALGRIND_CHECKING && defined VALGRIND_GET_VBITS
+  vec<char> vbits = vNULL;
+#endif
+
+  /* Actually write out the objects.  */
+  for (i = 0; i < state.count; i++)
+    {
+      if (this_object_size < state.ptrs[i]->size)
+	{
+	  this_object_size = state.ptrs[i]->size;
+	  this_object = XRESIZEVAR (char, this_object, this_object_size);
+	}
+#if defined ENABLE_VALGRIND_CHECKING && defined VALGRIND_GET_VBITS
+      /* obj might contain uninitialized bytes, e.g. in the trailing
+	 padding of the object.  Avoid warnings by making the memory
+	 temporarily defined and then restoring previous state.  */
+      int get_vbits = 0;
+      size_t valid_size = state.ptrs[i]->size;
+      if (__builtin_expect (RUNNING_ON_VALGRIND, 0))
+	{
+	  if (vbits.length () < valid_size)
+	    vbits.safe_grow (valid_size);
+	  get_vbits = VALGRIND_GET_VBITS (state.ptrs[i]->obj,
+					  vbits.address (), valid_size);
+	  if (get_vbits == 3)
+	    {
+	      /* We assume that first part of obj is addressable, and
+		 the rest is unaddressable.  Find out where the boundary is
+		 using binary search.  */
+	      size_t lo = 0, hi = valid_size;
+	      while (hi > lo)
+		{
+		  size_t mid = (lo + hi) / 2;
+		  get_vbits = VALGRIND_GET_VBITS ((char *) state.ptrs[i]->obj
+						  + mid, vbits.address (),
+						  1);
+		  if (get_vbits == 3)
+		    hi = mid;
+		  else if (get_vbits == 1)
+		    lo = mid + 1;
+		  else
+		    break;
+		}
+	      if (get_vbits == 1 || get_vbits == 3)
+		{
+		  valid_size = lo;
+		  get_vbits = VALGRIND_GET_VBITS (state.ptrs[i]->obj,
+						  vbits.address (),
+						  valid_size);
+		}
+	    }
+	  if (get_vbits == 1)
+	    VALGRIND_DISCARD (VALGRIND_MAKE_MEM_DEFINED (state.ptrs[i]->obj,
+							 state.ptrs[i]->size));
+	}
+#endif
+      memcpy (this_object, state.ptrs[i]->obj, state.ptrs[i]->size);
+      if (state.ptrs[i]->reorder_fn != NULL)
+	state.ptrs[i]->reorder_fn (state.ptrs[i]->obj,
+				   state.ptrs[i]->note_ptr_cookie,
+				   relocate_ptrs, &state);
+      state.ptrs[i]->note_ptr_fn (state.ptrs[i]->obj,
+				  state.ptrs[i]->note_ptr_cookie,
+				  relocate_ptrs, &state);
+      ggc_pch_write_object (state.d, state.f, state.ptrs[i]->obj,
+			    state.ptrs[i]->new_addr, state.ptrs[i]->size,
+			    state.ptrs[i]->note_ptr_fn == gt_pch_p_S);
+      if (state.ptrs[i]->note_ptr_fn != gt_pch_p_S)
+	memcpy (state.ptrs[i]->obj, this_object, state.ptrs[i]->size);
+#if defined ENABLE_VALGRIND_CHECKING && defined VALGRIND_GET_VBITS
+      if (__builtin_expect (get_vbits == 1, 0))
+	{
+	  (void) VALGRIND_SET_VBITS (state.ptrs[i]->obj, vbits.address (),
+				     valid_size);
+	  if (valid_size != state.ptrs[i]->size)
+	    VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS ((char *)
+							  state.ptrs[i]->obj
+							  + valid_size,
+							  state.ptrs[i]->size
+							  - valid_size));
+	}
+#endif
+    }
+#if defined ENABLE_VALGRIND_CHECKING && defined VALGRIND_GET_VBITS
+  vbits.release ();
+#endif
+
+  ggc_pch_finish (state.d, state.f);
+  gt_pch_fixup_stringpool ();
+
+  XDELETE (state.ptrs);
+  XDELETE (this_object);
+  saving_htab.dispose ();
+}
+
+/* Read the state of the compiler back in from F.  */
+
+void
+gt_pch_restore (FILE *f)
+{
+  const struct ggc_root_tab *const *rt;
+  const struct ggc_root_tab *rti;
+  size_t i;
+  struct mmap_info mmi;
+  int result;
+
+  /* Delete any deletable objects.  This makes ggc_pch_read much
+     faster, as it can be sure that no GCable objects remain other
+     than the ones just read in.  */
+  for (rt = gt_ggc_deletable_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      memset (rti->base, 0, rti->stride);
+
+  /* Read in all the scalar variables.  */
+  for (rt = gt_pch_scalar_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      if (fread (rti->base, rti->stride, 1, f) != 1)
+	fatal_error ("can%'t read PCH file: %m");
+
+  /* Read in all the global pointers, in 6 easy loops.  */
+  for (rt = gt_ggc_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      for (i = 0; i < rti->nelt; i++)
+	if (fread ((char *)rti->base + rti->stride * i,
+		   sizeof (void *), 1, f) != 1)
+	  fatal_error ("can%'t read PCH file: %m");
+
+  for (rt = gt_pch_cache_rtab; *rt; rt++)
+    for (rti = *rt; rti->base != NULL; rti++)
+      for (i = 0; i < rti->nelt; i++)
+	if (fread ((char *)rti->base + rti->stride * i,
+		   sizeof (void *), 1, f) != 1)
+	  fatal_error ("can%'t read PCH file: %m");
+
+  if (fread (&mmi, sizeof (mmi), 1, f) != 1)
+    fatal_error ("can%'t read PCH file: %m");
+
+  result = host_hooks.gt_pch_use_address (mmi.preferred_base, mmi.size,
+					  fileno (f), mmi.offset);
+  if (result < 0)
+    fatal_error ("had to relocate PCH");
+  if (result == 0)
+    {
+      if (fseek (f, mmi.offset, SEEK_SET) != 0
+	  || fread (mmi.preferred_base, mmi.size, 1, f) != 1)
+	fatal_error ("can%'t read PCH file: %m");
+    }
+  else if (fseek (f, mmi.offset + mmi.size, SEEK_SET) != 0)
+    fatal_error ("can%'t read PCH file: %m");
+
+  ggc_pch_read (f, mmi.preferred_base);
+
+  gt_pch_restore_stringpool ();
+}
+
+/* Default version of HOST_HOOKS_GT_PCH_GET_ADDRESS when mmap is not present.
+   Select no address whatsoever, and let gt_pch_save choose what it will with
+   malloc, presumably.  */
+
+void *
+default_gt_pch_get_address (size_t size ATTRIBUTE_UNUSED,
+			    int fd ATTRIBUTE_UNUSED)
+{
+  return NULL;
+}
+
+/* Default version of HOST_HOOKS_GT_PCH_USE_ADDRESS when mmap is not present.
+   Allocate SIZE bytes with malloc.  Return 0 if the address we got is the
+   same as base, indicating that the memory has been allocated but needs to
+   be read in from the file.  Return -1 if the address differs, to relocation
+   of the PCH file would be required.  */
+
+int
+default_gt_pch_use_address (void *base, size_t size, int fd ATTRIBUTE_UNUSED,
+			    size_t offset ATTRIBUTE_UNUSED)
+{
+  void *addr = xmalloc (size);
+  return (addr == base) - 1;
+}
+
+/* Default version of HOST_HOOKS_GT_PCH_GET_ADDRESS.   Return the
+   alignment required for allocating virtual memory. Usually this is the
+   same as pagesize.  */
+
+size_t
+default_gt_pch_alloc_granularity (void)
+{
+  return getpagesize ();
+}
+
+#if HAVE_MMAP_FILE
+/* Default version of HOST_HOOKS_GT_PCH_GET_ADDRESS when mmap is present.
+   We temporarily allocate SIZE bytes, and let the kernel place the data
+   wherever it will.  If it worked, that's our spot, if not we're likely
+   to be in trouble.  */
+
+void *
+mmap_gt_pch_get_address (size_t size, int fd)
+{
+  void *ret;
+
+  ret = mmap (NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+  if (ret == (void *) MAP_FAILED)
+    ret = NULL;
+  else
+    munmap ((caddr_t) ret, size);
+
+  return ret;
+}
+
+/* Default version of HOST_HOOKS_GT_PCH_USE_ADDRESS when mmap is present.
+   Map SIZE bytes of FD+OFFSET at BASE.  Return 1 if we succeeded at
+   mapping the data at BASE, -1 if we couldn't.
+
+   This version assumes that the kernel honors the START operand of mmap
+   even without MAP_FIXED if START through START+SIZE are not currently
+   mapped with something.  */
+
+int
+mmap_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
+{
+  void *addr;
+
+  /* We're called with size == 0 if we're not planning to load a PCH
+     file at all.  This allows the hook to free any static space that
+     we might have allocated at link time.  */
+  if (size == 0)
+    return -1;
+
+  addr = mmap ((caddr_t) base, size, PROT_READ | PROT_WRITE, MAP_PRIVATE,
+	       fd, offset);
+
+  return addr == base ? 1 : -1;
+}
+#endif /* HAVE_MMAP_FILE */
+
+#if !defined ENABLE_GC_CHECKING && !defined ENABLE_GC_ALWAYS_COLLECT
+
+/* Modify the bound based on rlimits.  */
+static double
+ggc_rlimit_bound (double limit)
+{
+#if defined(HAVE_GETRLIMIT)
+  struct rlimit rlim;
+# if defined (RLIMIT_AS)
+  /* RLIMIT_AS is what POSIX says is the limit on mmap.  Presumably
+     any OS which has RLIMIT_AS also has a working mmap that GCC will use.  */
+  if (getrlimit (RLIMIT_AS, &rlim) == 0
+      && rlim.rlim_cur != (rlim_t) RLIM_INFINITY
+      && rlim.rlim_cur < limit)
+    limit = rlim.rlim_cur;
+# elif defined (RLIMIT_DATA)
+  /* ... but some older OSs bound mmap based on RLIMIT_DATA, or we
+     might be on an OS that has a broken mmap.  (Others don't bound
+     mmap at all, apparently.)  */
+  if (getrlimit (RLIMIT_DATA, &rlim) == 0
+      && rlim.rlim_cur != (rlim_t) RLIM_INFINITY
+      && rlim.rlim_cur < limit
+      /* Darwin has this horribly bogus default setting of
+	 RLIMIT_DATA, to 6144Kb.  No-one notices because RLIMIT_DATA
+	 appears to be ignored.  Ignore such silliness.  If a limit
+	 this small was actually effective for mmap, GCC wouldn't even
+	 start up.  */
+      && rlim.rlim_cur >= 8 * 1024 * 1024)
+    limit = rlim.rlim_cur;
+# endif /* RLIMIT_AS or RLIMIT_DATA */
+#endif /* HAVE_GETRLIMIT */
+
+  return limit;
+}
+
+/* Heuristic to set a default for GGC_MIN_EXPAND.  */
+static int
+ggc_min_expand_heuristic (void)
+{
+  double min_expand = physmem_total ();
+
+  /* Adjust for rlimits.  */
+  min_expand = ggc_rlimit_bound (min_expand);
+
+  /* The heuristic is a percentage equal to 30% + 70%*(RAM/1GB), yielding
+     a lower bound of 30% and an upper bound of 100% (when RAM >= 1GB).  */
+  min_expand /= 1024*1024*1024;
+  min_expand *= 70;
+  min_expand = MIN (min_expand, 70);
+  min_expand += 30;
+
+  return min_expand;
+}
+
+/* Heuristic to set a default for GGC_MIN_HEAPSIZE.  */
+static int
+ggc_min_heapsize_heuristic (void)
+{
+  double phys_kbytes = physmem_total ();
+  double limit_kbytes = ggc_rlimit_bound (phys_kbytes * 2);
+
+  phys_kbytes /= 1024; /* Convert to Kbytes.  */
+  limit_kbytes /= 1024;
+
+  /* The heuristic is RAM/8, with a lower bound of 4M and an upper
+     bound of 128M (when RAM >= 1GB).  */
+  phys_kbytes /= 8;
+
+#if defined(HAVE_GETRLIMIT) && defined (RLIMIT_RSS)
+  /* Try not to overrun the RSS limit while doing garbage collection.
+     The RSS limit is only advisory, so no margin is subtracted.  */
+ {
+   struct rlimit rlim;
+   if (getrlimit (RLIMIT_RSS, &rlim) == 0
+       && rlim.rlim_cur != (rlim_t) RLIM_INFINITY)
+     phys_kbytes = MIN (phys_kbytes, rlim.rlim_cur / 1024);
+ }
+# endif
+
+  /* Don't blindly run over our data limit; do GC at least when the
+     *next* GC would be within 20Mb of the limit or within a quarter of
+     the limit, whichever is larger.  If GCC does hit the data limit,
+     compilation will fail, so this tries to be conservative.  */
+  limit_kbytes = MAX (0, limit_kbytes - MAX (limit_kbytes / 4, 20 * 1024));
+  limit_kbytes = (limit_kbytes * 100) / (110 + ggc_min_expand_heuristic ());
+  phys_kbytes = MIN (phys_kbytes, limit_kbytes);
+
+  phys_kbytes = MAX (phys_kbytes, 4 * 1024);
+  phys_kbytes = MIN (phys_kbytes, 128 * 1024);
+
+  return phys_kbytes;
+}
+#endif
+
+void
+init_ggc_heuristics (void)
+{
+#if !defined ENABLE_GC_CHECKING && !defined ENABLE_GC_ALWAYS_COLLECT
+  set_default_param_value (GGC_MIN_EXPAND, ggc_min_expand_heuristic ());
+  set_default_param_value (GGC_MIN_HEAPSIZE, ggc_min_heapsize_heuristic ());
+#endif
+}
+
+/* Datastructure used to store per-call-site statistics.  */
+struct loc_descriptor
+{
+  const char *file;
+  int line;
+  const char *function;
+  int times;
+  size_t allocated;
+  size_t overhead;
+  size_t freed;
+  size_t collected;
+};
+
+/* Hash table helper.  */
+
+struct loc_desc_hasher : typed_noop_remove <loc_descriptor>
+{
+  typedef loc_descriptor value_type;
+  typedef loc_descriptor compare_type;
+  static inline hashval_t hash (const value_type *);
+  static inline bool equal (const value_type *, const compare_type *);
+};
+
+inline hashval_t
+loc_desc_hasher::hash (const value_type *d)
+{
+  return htab_hash_pointer (d->function) | d->line;
+}
+
+inline bool
+loc_desc_hasher::equal (const value_type *d, const compare_type *d2)
+{
+  return (d->file == d2->file && d->line == d2->line
+	  && d->function == d2->function);
+}
+
+/* Hashtable used for statistics.  */
+static hash_table <loc_desc_hasher> loc_hash;
+
+struct ptr_hash_entry
+{
+  void *ptr;
+  struct loc_descriptor *loc;
+  size_t size;
+};
+
+/* Helper for ptr_hash table.  */
+
+struct ptr_hash_hasher : typed_noop_remove <ptr_hash_entry>
+{
+  typedef ptr_hash_entry value_type;
+  typedef void compare_type;
+  static inline hashval_t hash (const value_type *);
+  static inline bool equal (const value_type *, const compare_type *);
+};
+
+inline hashval_t
+ptr_hash_hasher::hash (const value_type *d)
+{
+  return htab_hash_pointer (d->ptr);
+}
+
+inline bool
+ptr_hash_hasher::equal (const value_type *p, const compare_type *p2)
+{
+  return (p->ptr == p2);
+}
+
+/* Hashtable converting address of allocated field to loc descriptor.  */
+static hash_table <ptr_hash_hasher> ptr_hash;
+
+/* Return descriptor for given call site, create new one if needed.  */
+static struct loc_descriptor *
+make_loc_descriptor (const char *name, int line, const char *function)
+{
+  struct loc_descriptor loc;
+  struct loc_descriptor **slot;
+
+  loc.file = name;
+  loc.line = line;
+  loc.function = function;
+  if (!loc_hash.is_created ())
+    loc_hash.create (10);
+
+  slot = loc_hash.find_slot (&loc, INSERT);
+  if (*slot)
+    return *slot;
+  *slot = XCNEW (struct loc_descriptor);
+  (*slot)->file = name;
+  (*slot)->line = line;
+  (*slot)->function = function;
+  return *slot;
+}
+
+/* Record ALLOCATED and OVERHEAD bytes to descriptor NAME:LINE (FUNCTION).  */
+void
+ggc_record_overhead (size_t allocated, size_t overhead, void *ptr,
+		     const char *name, int line, const char *function)
+{
+  struct loc_descriptor *loc = make_loc_descriptor (name, line, function);
+  struct ptr_hash_entry *p = XNEW (struct ptr_hash_entry);
+  ptr_hash_entry **slot;
+
+  p->ptr = ptr;
+  p->loc = loc;
+  p->size = allocated + overhead;
+  if (!ptr_hash.is_created ())
+    ptr_hash.create (10);
+  slot = ptr_hash.find_slot_with_hash (ptr, htab_hash_pointer (ptr), INSERT);
+  gcc_assert (!*slot);
+  *slot = p;
+
+  loc->times++;
+  loc->allocated+=allocated;
+  loc->overhead+=overhead;
+}
+
+/* Helper function for prune_overhead_list.  See if SLOT is still marked and
+   remove it from hashtable if it is not.  */
+int
+ggc_prune_ptr (ptr_hash_entry **slot, void *b ATTRIBUTE_UNUSED)
+{
+  struct ptr_hash_entry *p = *slot;
+  if (!ggc_marked_p (p->ptr))
+    {
+      p->loc->collected += p->size;
+      ptr_hash.clear_slot (slot);
+      free (p);
+    }
+  return 1;
+}
+
+/* After live values has been marked, walk all recorded pointers and see if
+   they are still live.  */
+void
+ggc_prune_overhead_list (void)
+{
+  ptr_hash.traverse <void *, ggc_prune_ptr> (NULL);
+}
+
+/* Notice that the pointer has been freed.  */
+void
+ggc_free_overhead (void *ptr)
+{
+  ptr_hash_entry **slot;
+  slot = ptr_hash.find_slot_with_hash (ptr, htab_hash_pointer (ptr), NO_INSERT);
+  struct ptr_hash_entry *p;
+  /* The pointer might be not found if a PCH read happened between allocation
+     and ggc_free () call.  FIXME: account memory properly in the presence of
+     PCH. */
+  if (!slot)
+      return;
+  p = (struct ptr_hash_entry *) *slot;
+  p->loc->freed += p->size;
+  ptr_hash.clear_slot (slot);
+  free (p);
+}
+
+/* Helper for qsort; sort descriptors by amount of memory consumed.  */
+static int
+final_cmp_statistic (const void *loc1, const void *loc2)
+{
+  const struct loc_descriptor *const l1 =
+    *(const struct loc_descriptor *const *) loc1;
+  const struct loc_descriptor *const l2 =
+    *(const struct loc_descriptor *const *) loc2;
+  long diff;
+  diff = ((long)(l1->allocated + l1->overhead - l1->freed) -
+	  (l2->allocated + l2->overhead - l2->freed));
+  return diff > 0 ? 1 : diff < 0 ? -1 : 0;
+}
+
+/* Helper for qsort; sort descriptors by amount of memory consumed.  */
+static int
+cmp_statistic (const void *loc1, const void *loc2)
+{
+  const struct loc_descriptor *const l1 =
+    *(const struct loc_descriptor *const *) loc1;
+  const struct loc_descriptor *const l2 =
+    *(const struct loc_descriptor *const *) loc2;
+  long diff;
+
+  diff = ((long)(l1->allocated + l1->overhead - l1->freed - l1->collected) -
+	  (l2->allocated + l2->overhead - l2->freed - l2->collected));
+  if (diff)
+    return diff > 0 ? 1 : diff < 0 ? -1 : 0;
+  diff =  ((long)(l1->allocated + l1->overhead - l1->freed) -
+	   (l2->allocated + l2->overhead - l2->freed));
+  return diff > 0 ? 1 : diff < 0 ? -1 : 0;
+}
+
+/* Collect array of the descriptors from hashtable.  */
+static struct loc_descriptor **loc_array;
+int
+ggc_add_statistics (loc_descriptor **slot, int *n)
+{
+  loc_array[*n] = *slot;
+  (*n)++;
+  return 1;
+}
+
+/* Dump per-site memory statistics.  */
+
+void
+dump_ggc_loc_statistics (bool final)
+{
+  int nentries = 0;
+  char s[4096];
+  size_t collected = 0, freed = 0, allocated = 0, overhead = 0, times = 0;
+  int i;
+
+  if (! GATHER_STATISTICS)
+    return;
+
+  ggc_force_collect = true;
+  ggc_collect ();
+
+  loc_array = XCNEWVEC (struct loc_descriptor *,
+			loc_hash.elements_with_deleted ());
+  fprintf (stderr, "-------------------------------------------------------\n");
+  fprintf (stderr, "\n%-48s %10s       %10s       %10s       %10s       %10s\n",
+	   "source location", "Garbage", "Freed", "Leak", "Overhead", "Times");
+  fprintf (stderr, "-------------------------------------------------------\n");
+  loc_hash.traverse <int *, ggc_add_statistics> (&nentries);
+  qsort (loc_array, nentries, sizeof (*loc_array),
+	 final ? final_cmp_statistic : cmp_statistic);
+  for (i = 0; i < nentries; i++)
+    {
+      struct loc_descriptor *d = loc_array[i];
+      allocated += d->allocated;
+      times += d->times;
+      freed += d->freed;
+      collected += d->collected;
+      overhead += d->overhead;
+    }
+  for (i = 0; i < nentries; i++)
+    {
+      struct loc_descriptor *d = loc_array[i];
+      if (d->allocated)
+	{
+	  const char *s1 = d->file;
+	  const char *s2;
+	  while ((s2 = strstr (s1, "gcc/")))
+	    s1 = s2 + 4;
+	  sprintf (s, "%s:%i (%s)", s1, d->line, d->function);
+	  s[48] = 0;
+	  fprintf (stderr, "%-48s %10li:%4.1f%% %10li:%4.1f%% %10li:%4.1f%% %10li:%4.1f%% %10li\n", s,
+		   (long)d->collected,
+		   (d->collected) * 100.0 / collected,
+		   (long)d->freed,
+		   (d->freed) * 100.0 / freed,
+		   (long)(d->allocated + d->overhead - d->freed - d->collected),
+		   (d->allocated + d->overhead - d->freed - d->collected) * 100.0
+		   / (allocated + overhead - freed - collected),
+		   (long)d->overhead,
+		   d->overhead * 100.0 / overhead,
+		   (long)d->times);
+	}
+    }
+  fprintf (stderr, "%-48s %10ld       %10ld       %10ld       %10ld       %10ld\n",
+	   "Total", (long)collected, (long)freed,
+	   (long)(allocated + overhead - freed - collected), (long)overhead,
+	   (long)times);
+  fprintf (stderr, "%-48s %10s       %10s       %10s       %10s       %10s\n",
+	   "source location", "Garbage", "Freed", "Leak", "Overhead", "Times");
+  fprintf (stderr, "-------------------------------------------------------\n");
+  ggc_force_collect = false;
+}