Patchwork [google,gcc-4_8] port gcov-tool to gcc-4_8

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Submitter Rong Xu
Date Jan. 17, 2014, 8:59 p.m.
Message ID <CAF1bQ=TJXdX4Ab+jyqY2nBqO0PmLFy7F12Wto-rQkc9Ge=CuDg@mail.gmail.com>
Download mbox | patch
Permalink /patch/312205/
State New
Headers show

Comments

Rong Xu - Jan. 17, 2014, 8:59 p.m.
last attachment is not the complete patch. Re-send again.

On Fri, Jan 17, 2014 at 12:51 PM, Rong Xu <xur@google.com> wrote:
> Do we have to split params.def?
>
> I can include params.h and link in params.o (a special version as we
> don't have some global vars).
>
> As for lipo_cutoff, I think we don't need a special handling -- we
> should use the default value of 100 and let logic in dyn-ipa.c takes
> care of the rest.
>
> Please find the update patch which reads the default values from params.def.
>
> -Rong
>
> On Fri, Jan 17, 2014 at 12:05 PM, Xinliang David Li <davidxl@google.com> wrote:
>> For LIPO parameters, you can do this
>> 1) isolate all LIPO specific parameters into lipo_params.def, and
>> include it from params.def.
>> 2) include lipo_params.def (after proper definition of DEFPARAM) in
>> the profile tool source dir.
>>
>> By so doing, the compiler setting and profile tool will be in sync.
>> (Unfortuately, for historic reason, the lipo_cutoff default val is
>> still set in dyn-ipa.c even with the parameter, so some comments needs
>> to be added in dyn-ipa.c to make sure the value should be doubly
>> updated).
>>
>> David
>>
>> On Fri, Jan 17, 2014 at 11:15 AM, Rong Xu <xur@google.com> wrote:
>>> Hi,
>>>
>>> This patch port the gcov-tool work to google/gcc-4_8 branches.
>>>
>>> Tested with spec2006, profiledbootstrap and google internal benchmarks.
>>>
>>> -Rong
Xinliang David Li - Jan. 17, 2014, 9:19 p.m.
Ok for google branch. It might be good to think about adding
regression tests (similar to those gcov tests under g++.dg/gcov, but
handling multiple files).

David

On Fri, Jan 17, 2014 at 12:59 PM, Rong Xu <xur@google.com> wrote:
> last attachment is not the complete patch. Re-send again.
>
> On Fri, Jan 17, 2014 at 12:51 PM, Rong Xu <xur@google.com> wrote:
>> Do we have to split params.def?
>>
>> I can include params.h and link in params.o (a special version as we
>> don't have some global vars).
>>
>> As for lipo_cutoff, I think we don't need a special handling -- we
>> should use the default value of 100 and let logic in dyn-ipa.c takes
>> care of the rest.
>>
>> Please find the update patch which reads the default values from params.def.
>>
>> -Rong
>>
>> On Fri, Jan 17, 2014 at 12:05 PM, Xinliang David Li <davidxl@google.com> wrote:
>>> For LIPO parameters, you can do this
>>> 1) isolate all LIPO specific parameters into lipo_params.def, and
>>> include it from params.def.
>>> 2) include lipo_params.def (after proper definition of DEFPARAM) in
>>> the profile tool source dir.
>>>
>>> By so doing, the compiler setting and profile tool will be in sync.
>>> (Unfortuately, for historic reason, the lipo_cutoff default val is
>>> still set in dyn-ipa.c even with the parameter, so some comments needs
>>> to be added in dyn-ipa.c to make sure the value should be doubly
>>> updated).
>>>
>>> David
>>>
>>> On Fri, Jan 17, 2014 at 11:15 AM, Rong Xu <xur@google.com> wrote:
>>>> Hi,
>>>>
>>>> This patch port the gcov-tool work to google/gcc-4_8 branches.
>>>>
>>>> Tested with spec2006, profiledbootstrap and google internal benchmarks.
>>>>
>>>> -Rong

Patch

Index: libgcc/libgcov-driver.c
===================================================================
--- libgcc/libgcov-driver.c	(revision 206671)
+++ libgcc/libgcov-driver.c	(working copy)
@@ -53,6 +53,7 @@  extern int get_gcov_dump_complete (void) ATTRIBUTE
 extern void set_gcov_list (struct gcov_info *) ATTRIBUTE_HIDDEN;
 extern struct gcov_info *get_gcov_list (void) ATTRIBUTE_HIDDEN;
 
+#ifndef IN_GCOV_TOOL
 /* Create a strong reference to these symbols so that they are
    unconditionally pulled into the instrumented binary, even when
    the only reference is a weak reference. This is necessary because
@@ -76,6 +77,7 @@  __coverage_callback (gcov_type funcdef_no __attrib
 {
    /* nothing */
 }
+#endif
 
 /* Flag when the profile has already been dumped via __gcov_dump().  */
 static int gcov_dump_complete;
@@ -135,8 +137,11 @@  get_gcov_list (void)
 /* Size of the longest file name. */
 static size_t gcov_max_filename = 0;
 
+#ifndef IN_GCOV_TOOL
+/* Emitted in coverage.c.  */
 extern gcov_unsigned_t __gcov_sampling_period;
 static int gcov_sampling_period_initialized = 0;
+#endif
 
 /* Unique identifier assigned to each module (object file).  */
 static gcov_unsigned_t gcov_cur_module_id = 0;
@@ -384,7 +389,7 @@  gcov_exit_merge_gcda (struct gcov_info *gi_ptr,
              histogram entries that will be emitted, and thus the
              size of the merged summary.  */
           (*sum_tail) = (struct gcov_summary_buffer *)
-              malloc (sizeof(struct gcov_summary_buffer));
+              xmalloc (sizeof(struct gcov_summary_buffer));
           (*sum_tail)->summary = tmp;
           (*sum_tail)->next = 0;
           sum_tail = &((*sum_tail)->next);
@@ -852,7 +857,8 @@  gcov_exit (void)
 
       /* The IS_PRIMARY field is overloaded to indicate if this module
          is FDO/LIPO.  */
-      dump_module_info |= gi_ptr->mod_info->is_primary;
+      if (gi_ptr->mod_info)
+        dump_module_info |= gi_ptr->mod_info->is_primary;
     }
 
   if (dump_module_info)
@@ -898,6 +904,7 @@  gcov_clear (void)
 void
 __gcov_init (struct gcov_info *info)
 {
+#ifndef IN_GCOV_TOOL
   if (!gcov_sampling_period_initialized)
     {
       const char* env_value_str = getenv ("GCOV_SAMPLING_PERIOD");
@@ -909,6 +916,7 @@  __gcov_init (struct gcov_info *info)
         }
       gcov_sampling_period_initialized = 1;
     }
+#endif /* IN_GCOV_TOOL */
 
   if (!info->version || !info->n_functions)
     return;
Index: libgcc/libgcov.h
===================================================================
--- libgcc/libgcov.h	(revision 206671)
+++ libgcc/libgcov.h	(working copy)
@@ -34,7 +34,13 @@  see the files COPYING3 and COPYING.RUNTIME respect
 #ifndef xcalloc
 #define xcalloc calloc
 #endif
+#ifndef xrealloc
+#define xrealloc realloc
+#endif
 
+#ifndef IN_GCOV_TOOL
+/* About the target.  */
+
 #include "tconfig.h"
 #include "tsystem.h"
 #include "coretypes.h"
@@ -47,6 +53,25 @@  see the files COPYING3 and COPYING.RUNTIME respect
 #define THREAD_PREFIX
 #endif
 
+#else /* IN_GCOV_TOOL */
+/* About the host.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+
+typedef unsigned gcov_unsigned_t;
+typedef unsigned gcov_position_t;
+/* gcov_type is typedef'd elsewhere for the compiler */
+#if defined (HOST_HAS_F_SETLKW)
+#define GCOV_LOCKED 1
+#else
+#define GCOV_LOCKED 0
+#endif
+
+#endif /* !IN_GCOV_TOOL */
+
 #if defined(inhibit_libc)
 #define IN_LIBGCOV (-1)
 #else
@@ -203,8 +228,13 @@  struct gcov_info
 					  unused) */
 
   unsigned n_functions;		/* number of functions */
+
+#ifndef IN_GCOV_TOOL
   const struct gcov_fn_info *const *functions; /* pointer to pointers
-					          to function information  */
+                                                  to function information  */
+#else
+  const struct gcov_fn_info **functions;
+#endif /* !IN_GCOV_TOOL */
 };
 
 /* Information about a single imported module.  */
Index: libgcc/dyn-ipa.c
===================================================================
--- libgcc/dyn-ipa.c	(revision 206671)
+++ libgcc/dyn-ipa.c	(working copy)
@@ -28,11 +28,13 @@  see the files COPYING3 and COPYING.RUNTIME respect
 
 struct dyn_pointer_set;
 
+#ifndef IN_GCOV_TOOL
 #define XNEWVEC(type,ne) (type *)malloc(sizeof(type) * (ne))
 #define XCNEWVEC(type,ne) (type *)calloc(1, sizeof(type) * (ne))
 #define XNEW(type) (type *)malloc(sizeof(type))
 #define XDELETEVEC(p) free(p)
 #define XDELETE(p) free(p)
+#endif
 
 struct dyn_cgraph_node
 {
@@ -262,7 +264,7 @@  get_cgraph_node (gcov_type func_guid)
   if (func_id > the_dyn_call_graph.sup_modules[mod_idx].max_func_ident)
     return 0;
 
-  return *(pointer_set_find_or_insert
+  return (struct dyn_cgraph_node*) *(pointer_set_find_or_insert
 	   (the_dyn_call_graph.call_graph_nodes[mod_idx], func_id));
 }
 
@@ -486,7 +488,7 @@  __gcov_finalize_dyn_callgraph (void)
           struct dyn_cgraph_node *node;
           struct dyn_cgraph_edge *callees, *next_callee;
           fi_ptr = gi_ptr->functions[f_ix];
-          node = *(pointer_set_find_or_insert
+          node = (struct dyn_cgraph_node *) *(pointer_set_find_or_insert
                    (the_dyn_call_graph.call_graph_nodes[i], fi_ptr->ident));
           gcc_assert (node);
           callees = node->callees;
@@ -658,7 +660,7 @@  gcov_build_callgraph (void)
           fi_ptr = gi_ptr->functions[f_ix];
           ci_ptr = fi_ptr->ctrs;
 
-          caller = *(pointer_set_find_or_insert
+          caller = (struct dyn_cgraph_node *) *(pointer_set_find_or_insert
                     (the_dyn_call_graph.call_graph_nodes[m_ix],
                      fi_ptr->ident));
           gcc_assert (caller);
@@ -907,7 +909,7 @@  gcov_compute_cutoff_count (void)
 
 	  fi_ptr = gi_ptr->functions[f_ix];
 
-	  node = *(pointer_set_find_or_insert
+	  node = (struct dyn_cgraph_node *) *(pointer_set_find_or_insert
 		   (the_dyn_call_graph.call_graph_nodes[m_ix], fi_ptr->ident));
 	  gcc_assert (node);
 
@@ -920,7 +922,7 @@  gcov_compute_cutoff_count (void)
               else
                 {
                   capacity = capacity + (capacity >> 1);
-                  edges = (struct dyn_cgraph_edge **)realloc (edges, sizeof (void*) * capacity);
+                  edges = (struct dyn_cgraph_edge **)xrealloc (edges, sizeof (void*) * capacity);
                   edges[num_edges - 1] = callees;
                 }
               callees = callees->next_callee;
@@ -1267,7 +1269,7 @@  static fibnode_t fibnode_remove (fibnode_t);
 static dyn_fibheap_t
 dyn_fibheap_new (void)
 {
-  return (dyn_fibheap_t) calloc (1, sizeof (struct dyn_fibheap));
+  return (dyn_fibheap_t) xcalloc (1, sizeof (struct dyn_fibheap));
 }
 
 /* Create a new fibonacci heap node.  */
@@ -1276,7 +1278,7 @@  fibnode_new (void)
 {
   fibnode_t node;
 
-  node = (fibnode_t) calloc (1, sizeof *node);
+  node = (fibnode_t) xcalloc (1, sizeof *node);
   node->left = node;
   node->right = node;
 
@@ -1634,7 +1636,7 @@  build_modu_graph (gcov_type cutoff_count)
 	  struct dyn_cgraph_node *node;
 
 	  fi_ptr = gi_ptr->functions[f_ix];
-	  node = *(pointer_set_find_or_insert
+	  node = (struct dyn_cgraph_node *) *(pointer_set_find_or_insert
 		   (the_dyn_call_graph.call_graph_nodes[m_ix], fi_ptr->ident));
 	  if (!node)
             {
@@ -1954,7 +1956,7 @@  gcov_compute_module_groups_eager_propagation (gcov
 	  struct dyn_cgraph_node *node;
 
 	  fi_ptr = gi_ptr->functions[f_ix];
-	  node = *(pointer_set_find_or_insert
+	  node = (struct dyn_cgraph_node *) *(pointer_set_find_or_insert
 		   (the_dyn_call_graph.call_graph_nodes[m_ix], fi_ptr->ident));
 	  gcc_assert (node);
           if (node->visited)
@@ -1978,7 +1980,7 @@  gcov_compute_module_groups_eager_propagation (gcov
           struct dyn_pointer_set *imp_modules;
 
 	  fi_ptr = gi_ptr->functions[f_ix];
-	  node = *(pointer_set_find_or_insert
+	  node = (struct dyn_cgraph_node *) *(pointer_set_find_or_insert
 		   (the_dyn_call_graph.call_graph_nodes[m_ix], fi_ptr->ident));
 	  gcc_assert (node);
 
@@ -2337,7 +2339,7 @@  gcov_dump_callgraph (gcov_type cutoff_count)
 	  struct dyn_cgraph_node *node;
 
 	  fi_ptr = gi_ptr->functions[f_ix];
-	  node = *(pointer_set_find_or_insert
+	  node = (struct dyn_cgraph_node *) *(pointer_set_find_or_insert
 		   (the_dyn_call_graph.call_graph_nodes[m_ix], fi_ptr->ident));
 	  gcc_assert (node);
 
Index: libgcc/libgcov-merge.c
===================================================================
--- libgcc/libgcov-merge.c	(revision 206671)
+++ libgcc/libgcov-merge.c	(working copy)
@@ -45,6 +45,26 @@  void __gcov_merge_delta (gcov_type *counters  __at
 
 #else
 
+static inline gcov_type
+gcov_get_counter (void)
+{
+#ifndef IN_GCOV_TOOL
+  return gcov_read_counter ();
+#else
+  return gcov_read_counter_mem () * gcov_get_merge_weight ();
+#endif
+}
+
+static inline gcov_type
+gcov_get_counter_target (void)
+{
+#ifndef IN_GCOV_TOOL
+  return gcov_read_counter ();
+#else
+  return gcov_read_counter_mem ();
+#endif
+}
+
 #ifdef L_gcov_merge_add
 /* The profile merging function that just adds the counters.  It is given
    an array COUNTERS of N_COUNTERS old counters and it reads the same number
@@ -53,7 +73,7 @@  void
 __gcov_merge_add (gcov_type *counters, unsigned n_counters)
 {
   for (; n_counters; counters++, n_counters--)
-    *counters += gcov_read_counter ();
+    *counters += gcov_get_counter ();
 }
 #endif /* L_gcov_merge_add */
 
@@ -65,7 +85,7 @@  void
 __gcov_merge_ior (gcov_type *counters, unsigned n_counters)
 {
   for (; n_counters; counters++, n_counters--)
-    *counters |= gcov_read_counter ();
+    *counters |= gcov_get_counter ();
 }
 #endif
 
@@ -94,8 +114,8 @@  __gcov_merge_dc (gcov_type *counters, unsigned n_c
   gcc_assert (!(n_counters % 2));
   for (i = 0; i < n_counters; i += 2)
     {
-      gcov_type global_id = gcov_read_counter ();
-      gcov_type call_count = gcov_read_counter ();
+      gcov_type global_id = gcov_get_counter_target ();
+      gcov_type call_count = gcov_get_counter ();
 
       /* Note that global id counter may never have been set if no calls were
 	 made from this call-site.  */
@@ -156,12 +176,12 @@  __gcov_merge_icall_topn (gcov_type *counters, unsi
         }
 
       /* Skip the number_of_eviction entry.  */
-      gcov_read_counter ();
+      gcov_get_counter ();
       for (k = 0; k < GCOV_ICALL_TOPN_NCOUNTS - 1; k += 2)
         {
           int found = 0;
-          gcov_type global_id = gcov_read_counter ();
-          gcov_type call_count = gcov_read_counter ();
+          gcov_type global_id = gcov_get_counter_target ();
+          gcov_type call_count = gcov_get_counter ();
           for (m = 0; m < j; m += 2)
             {
               if (tmp_array[m] == global_id)
@@ -212,9 +232,9 @@  __gcov_merge_single (gcov_type *counters, unsigned
   n_measures = n_counters / 3;
   for (i = 0; i < n_measures; i++, counters += 3)
     {
-      value = gcov_read_counter ();
-      counter = gcov_read_counter ();
-      all = gcov_read_counter ();
+      value = gcov_get_counter_target ();
+      counter = gcov_get_counter ();
+      all = gcov_get_counter ();
 
       if (counters[0] == value)
 	counters[1] += counter;
@@ -251,10 +271,10 @@  __gcov_merge_delta (gcov_type *counters, unsigned
   n_measures = n_counters / 4;
   for (i = 0; i < n_measures; i++, counters += 4)
     {
-      /* last = */ gcov_read_counter ();
-      value = gcov_read_counter ();
-      counter = gcov_read_counter ();
-      all = gcov_read_counter ();
+      /* last = */ gcov_get_counter ();
+      value = gcov_get_counter_target  ();
+      counter = gcov_get_counter ();
+      all = gcov_get_counter ();
 
       if (counters[1] == value)
 	counters[2] += counter;
Index: libgcc/libgcov-util.c
===================================================================
--- libgcc/libgcov-util.c	(revision 0)
+++ libgcc/libgcov-util.c	(revision 0)
@@ -0,0 +1,1049 @@ 
+/* Utility functions for reading gcda files into in-memory
+   gcov_info structures and offline profile processing. */
+/* Copyright (C) 2014 Free Software Foundation, Inc.
+   Contributed by Rong Xu <xur@google.com>.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+
+#define IN_GCOV_TOOL 1
+#define L_gcov 1
+#define L_gcov_merge_add 1
+#define L_gcov_merge_single 1
+#define L_gcov_merge_delta 1
+#define L_gcov_merge_icall_topn 1
+#define L_gcov_merge_dc 1
+#define L_gcov_merge_ior 1
+#define L_gcov_merge_reusedist 1
+
+#include "libgcov.h"
+#include "intl.h"
+#include "diagnostic.h"
+#include "version.h"
+#include "demangle.h"
+
+extern gcov_type gcov_read_counter_mem();
+extern unsigned gcov_get_merge_weight();
+
+/* We need the dumping and merge part of code in libgcov.  */
+#include "libgcov-driver.c"
+#include "libgcov-merge.c"
+
+/* Verbose mode for debug.  */
+static int verbose;
+
+/* Set verbose flag.  */
+void gcov_set_verbose (void)
+{
+  verbose = 1;
+}
+
+/* The following part is to read Gcda and reconstruct GCOV_INFO.  */
+
+#include "obstack.h"
+#include <unistd.h>
+#include <ftw.h>
+
+static void tag_function (unsigned, unsigned);
+static void tag_blocks (unsigned, unsigned);
+static void tag_arcs (unsigned, unsigned);
+static void tag_lines (unsigned, unsigned);
+static void tag_counters (unsigned, unsigned);
+static void tag_summary (unsigned, unsigned);
+static void tag_module_info (unsigned, unsigned);
+
+/* The gcov_info for the first module.  */
+static struct gcov_info *curr_gcov_info;
+/* The gcov_info being processed.  */
+static struct gcov_info *gcov_info_head;
+/* This variable points to the module being processed.  */
+static struct gcov_module_info *curr_module_info;
+/* This variable contains all the functions in current module.  */
+static struct obstack fn_info;
+/* The function being processed.  */
+static struct gcov_fn_info *curr_fn_info;
+/* The number of functions seen so far.  */
+static unsigned num_fn_info;
+/* This variable contains all the counters for current module.  */
+static int k_ctrs_mask[GCOV_COUNTERS];
+/* The kind of counters that have been seen.  */
+static struct gcov_ctr_info k_ctrs[GCOV_COUNTERS];
+/* Number of kind of counters that have been seen.  */
+static int k_ctrs_types;
+/* The longest length of all the filenames.  */
+static int max_filename_len;
+
+/* Merge functions for counters.  */
+static gcov_merge_fn ctr_merge_functions[GCOV_COUNTERS] = {
+    __gcov_merge_add,
+    __gcov_merge_add,
+    __gcov_merge_add,
+    __gcov_merge_single,
+    __gcov_merge_delta,
+    __gcov_merge_single,
+    __gcov_merge_add,
+    __gcov_merge_ior,
+    __gcov_merge_icall_topn,
+    __gcov_merge_dc,
+};
+
+/* Set the ctrs field in gcvo_fn_info object FN_INFO.  */
+
+static void
+set_fn_ctrs (struct gcov_fn_info *fn_info)
+{
+  int j = 0, i;
+
+  for (i = 0; i < GCOV_COUNTERS; i++)
+    {
+      if (k_ctrs_mask[i] == 0)
+        continue;
+      fn_info->ctrs[j].num = k_ctrs[i].num;
+      fn_info->ctrs[j].values = k_ctrs[i].values;
+      j++;
+    }
+  if (k_ctrs_types == 0)
+    k_ctrs_types = j;
+  else
+    gcc_assert (j == k_ctrs_types);
+}
+
+typedef struct tag_format
+{
+    unsigned tag;
+    char const *name;
+    void (*proc) (unsigned, unsigned);
+} tag_format_t;
+
+static const tag_format_t tag_table[] =
+{
+  {0, "NOP", NULL},
+  {0, "UNKNOWN", NULL},
+  {0, "COUNTERS", tag_counters},
+  {GCOV_TAG_FUNCTION, "FUNCTION", tag_function},
+  {GCOV_TAG_BLOCKS, "BLOCKS", tag_blocks},
+  {GCOV_TAG_ARCS, "ARCS", tag_arcs},
+  {GCOV_TAG_LINES, "LINES", tag_lines},
+  {GCOV_TAG_OBJECT_SUMMARY, "OBJECT_SUMMARY", tag_summary},
+  {GCOV_TAG_PROGRAM_SUMMARY, "PROGRAM_SUMMARY", tag_summary},
+  {GCOV_TAG_MODULE_INFO, "MODULE INFO", tag_module_info},
+  {0, NULL, NULL}
+};
+
+/* Handler for reading function tag.  */
+
+static void
+tag_function (unsigned tag ATTRIBUTE_UNUSED, unsigned length ATTRIBUTE_UNUSED)
+{
+  int i;
+
+  /* write out previous fn_info.  */
+  if (num_fn_info)
+    {
+      set_fn_ctrs (curr_fn_info);
+      obstack_ptr_grow (&fn_info, curr_fn_info);
+    }
+
+  /* Here we over allocate a bit, using GCOV_COUNTERS instead of the actual active
+     counter types.  */
+  curr_fn_info = (struct gcov_fn_info *) xcalloc (sizeof (struct gcov_fn_info)
+                   + GCOV_COUNTERS * sizeof (struct gcov_ctr_info), 1);
+
+  for (i = 0; i < GCOV_COUNTERS; i++)
+     k_ctrs[i].num = 0;
+  k_ctrs_types = 0;
+
+  curr_fn_info->key = curr_gcov_info;
+  curr_fn_info->ident = gcov_read_unsigned ();
+  curr_fn_info->lineno_checksum = gcov_read_unsigned ();
+  curr_fn_info->cfg_checksum = gcov_read_unsigned ();
+  num_fn_info++;
+
+  if (verbose)
+    fprintf (stdout, "tag one function id=%d\n", curr_fn_info->ident);
+}
+
+/* Handler for reading block tag.  */
+
+static void
+tag_blocks (unsigned tag ATTRIBUTE_UNUSED, unsigned length ATTRIBUTE_UNUSED)
+{
+  gcc_assert (0);
+}
+
+/* Handler for reading flow arc tag.  */
+
+static void
+tag_arcs (unsigned tag ATTRIBUTE_UNUSED, unsigned length ATTRIBUTE_UNUSED)
+{
+  gcc_assert (0);
+}
+
+/* Handler for reading line tag.  */
+
+static void
+tag_lines (unsigned tag ATTRIBUTE_UNUSED, unsigned length ATTRIBUTE_UNUSED)
+{
+  gcc_assert (0);
+}
+
+/* Handler for reading counters array tag with value as TAG and length of LENGTH.  */
+
+static void
+tag_counters (unsigned tag, unsigned length)
+{
+  unsigned n_counts = GCOV_TAG_COUNTER_NUM (length);
+  gcov_type *values;
+  unsigned ix;
+  unsigned tag_ix;
+
+  tag_ix = GCOV_COUNTER_FOR_TAG (tag);
+  gcc_assert (tag_ix < GCOV_COUNTERS);
+  k_ctrs_mask [tag_ix] = 1;
+  gcc_assert (k_ctrs[tag_ix].num == 0);
+  k_ctrs[tag_ix].num = n_counts;
+
+  k_ctrs[tag_ix].values = values = (gcov_type *) xmalloc (n_counts * sizeof (gcov_type));
+  gcc_assert (values);
+
+  for (ix = 0; ix != n_counts; ix++)
+    values[ix] = gcov_read_counter ();
+}
+
+/* Handler for reading summary tag.  */
+
+static void
+tag_summary (unsigned tag ATTRIBUTE_UNUSED, unsigned length ATTRIBUTE_UNUSED)
+{
+  struct gcov_summary summary;
+
+  gcov_read_summary (&summary);
+}
+
+/* This function is called at the end of reading a gcda file.
+   It flushes the contents in curr_fn_info to gcov_info object OBJ_INFO.  */
+
+static void
+read_gcda_finalize (struct gcov_info *obj_info)
+{
+  int i;
+
+  set_fn_ctrs (curr_fn_info);
+  obstack_ptr_grow (&fn_info, curr_fn_info);
+
+  /* We set the following fields: merge, n_functions, and functions.  */
+  obj_info->n_functions = num_fn_info;
+  obj_info->functions = (const struct gcov_fn_info**) obstack_finish (&fn_info);
+
+  /* wrap all the counter array.  */
+  for (i=0; i< GCOV_COUNTERS; i++)
+    {
+      if (k_ctrs_mask[i])
+        obj_info->merge[i] = ctr_merge_functions[i];
+    }
+
+  obj_info->mod_info = curr_module_info;
+}
+
+extern void gcov_read_module_info (struct gcov_module_info *mod_info,
+    gcov_unsigned_t len);
+
+/* This function reads module_info from a gcda file.  */
+
+static void
+tag_module_info (unsigned tag ATTRIBUTE_UNUSED, unsigned length)
+{
+  struct gcov_module_info* mod_info;
+
+  mod_info = (struct gcov_module_info *)
+      xmalloc ((length + 2) * sizeof (gcov_unsigned_t));
+
+  gcov_read_module_info (mod_info, length);
+
+  if (mod_info->is_primary)
+    curr_module_info = mod_info;
+  else
+    free (mod_info);
+}
+
+/* Read the content of a gcda file FILENAME, and return a gcov_info data structure.
+   Program level summary CURRENT_SUMMARY will also be updated.  */
+
+static struct gcov_info *
+read_gcda_file (const char *filename)
+{
+  unsigned tags[4];
+  unsigned depth = 0;
+  unsigned magic, version;
+  struct gcov_info *obj_info;
+  int i;
+
+  for (i=0; i< GCOV_COUNTERS; i++)
+    k_ctrs_mask[i] = 0;
+  k_ctrs_types = 0;
+
+  if (!gcov_open (filename))
+    {
+      fprintf (stderr, "%s:cannot open\n", filename);
+      return NULL;
+    }
+
+  /* Read magic.  */
+  magic = gcov_read_unsigned ();
+  if (magic != GCOV_DATA_MAGIC)
+    {
+      fprintf (stderr, "%s:not a gcov data file\n", filename);
+      gcov_close ();
+      return NULL;
+    }
+
+  /* Read version.  */
+  version = gcov_read_unsigned ();
+  if (version != GCOV_VERSION)
+    {
+      fprintf (stderr, "%s:incorrect gcov version %d vs %d \n", filename, version, GCOV_VERSION);
+      gcov_close ();
+      return NULL;
+    }
+
+  /* Instantiate a gcov_info object.  */
+  curr_gcov_info = obj_info = (struct gcov_info *) xcalloc (sizeof (struct gcov_info) +
+             sizeof (struct gcov_ctr_info) * GCOV_COUNTERS, 1);
+
+  obj_info->version = version;
+  obstack_init (&fn_info);
+  num_fn_info = 0;
+  curr_fn_info = 0;
+  curr_module_info = 0;
+
+  {
+    char *str_dup = (char*) xmalloc (strlen (filename) + 1);
+    int len;
+
+    strcpy (str_dup, filename);
+    obj_info->filename = str_dup;
+    if ((len = strlen (filename)) > max_filename_len)
+      max_filename_len = len;
+  }
+
+  /* Read stamp.  */
+  obj_info->stamp = gcov_read_unsigned ();
+
+  while (1)
+    {
+      gcov_position_t base;
+      unsigned tag, length;
+      tag_format_t const *format;
+      unsigned tag_depth;
+      int error;
+      unsigned mask;
+
+      tag = gcov_read_unsigned ();
+      if (!tag)
+	break;
+      length = gcov_read_unsigned ();
+      base = gcov_position ();
+      mask = GCOV_TAG_MASK (tag) >> 1;
+      for (tag_depth = 4; mask; mask >>= 8)
+	{
+	  if (((mask & 0xff) != 0xff))
+	    {
+	      fprintf (stderr, "warning: %s:tag `%08x' is invalid\n", filename, tag);
+	      break;
+	    }
+	  tag_depth--;
+	}
+      for (format = tag_table; format->name; format++)
+	if (format->tag == tag)
+	  goto found;
+      format = &tag_table[GCOV_TAG_IS_COUNTER (tag) ? 2 : 1];
+    found:;
+      if (tag)
+	{
+	  if (depth && depth < tag_depth)
+	    {
+	      if (!GCOV_TAG_IS_SUBTAG (tags[depth - 1], tag))
+		fprintf (stderr, "warning: %s:tag `%08x' is incorrectly nested\n",
+			filename, tag);
+	    }
+	  depth = tag_depth;
+	  tags[depth - 1] = tag;
+	}
+
+      if (format->proc)
+        {
+	  unsigned long actual_length;
+
+	  (*format->proc) (tag, length);
+
+	  actual_length = gcov_position () - base;
+	  if (actual_length > length)
+	    fprintf (stderr,"warning: %s:record size mismatch %lu bytes overread\n",
+		    filename, actual_length - length);
+	  else if (length > actual_length)
+	    fprintf (stderr,"warning: %s:record size mismatch %lu bytes unread\n",
+		    filename, length - actual_length);
+	}
+
+      gcov_sync (base, length);
+      if ((error = gcov_is_error ()))
+	{
+	  fprintf (stderr,error < 0 ? "warning:%s:counter overflow at %lu\n" :
+		  "Warning:%s:read error at %lu\n", filename,
+		  (long unsigned) gcov_position ());
+	  break;
+	}
+    }
+
+  read_gcda_finalize (obj_info);
+  gcov_close ();
+
+  return obj_info;
+}
+
+/* This will be called by ftw(). It opens and read a gcda file FILENAME.
+   Return a non-zero value to stop the tree walk.  */
+
+static int
+ftw_read_file (const char *filename,
+               const struct stat *status ATTRIBUTE_UNUSED,
+               int type)
+{
+  int filename_len;
+  int suffix_len;
+  struct gcov_info *obj_info;
+
+  /* Only read regular files.  */
+  if (type != FTW_F)
+    return 0;
+
+  filename_len = strlen (filename);
+  suffix_len = strlen (GCOV_DATA_SUFFIX);
+
+  if (filename_len <= suffix_len)
+    return 0;
+
+  if (strcmp(filename + filename_len - suffix_len, GCOV_DATA_SUFFIX))
+    return 0;
+
+   if (verbose)
+    fprintf (stderr, "reading file: %s\n", filename);
+
+  obj_info = read_gcda_file (filename);
+
+  obj_info->next = gcov_info_head;
+  gcov_info_head = obj_info;
+
+  return 0;
+}
+
+/* Initializer for reading a profile dir.  */
+
+static inline void
+read_profile_dir_init (void)
+{
+  gcov_info_head = 0;
+}
+
+/* Driver for read a profile directory and convert into gcov_info list in memory.
+   Return NULL on error,
+   Return the head of gcov_info list on success.
+   Note the file static variable GCOV_MAX_FILENAME is also set.  */
+
+struct gcov_info *
+gcov_read_profile_dir (const char* dir_name, int recompute_summary ATTRIBUTE_UNUSED)
+{
+  char *pwd;
+  int ret;
+
+  read_profile_dir_init ();
+
+  if (access (dir_name, R_OK) != 0)
+    {
+      fprintf (stderr, "cannot access directory %s\n", dir_name);
+      return NULL;
+    }
+  pwd = getcwd (NULL, 0);
+  gcc_assert (pwd);
+  ret = chdir (dir_name);
+  if (ret !=0)
+    {
+      fprintf (stderr, "%s is not a directory\n", dir_name);
+      return NULL;
+    }
+  ftw (".", ftw_read_file, 50);
+  ret = chdir (pwd);
+  free (pwd);
+
+
+  /* gcov_max_filename is defined in libgcov.c that records the
+     max filename len. We need to set it here to allocate the
+     array for dumping.  */
+  gcov_max_filename = max_filename_len;
+
+  return gcov_info_head;;
+}
+
+/* This part of the code is to merge profile counters.  */
+
+static gcov_type *gcov_value_buf;
+static gcov_unsigned_t gcov_value_buf_size;
+static gcov_unsigned_t gcov_value_buf_pos;
+static unsigned gcov_merge_weight;
+
+/* Read a counter value from gcov_value_buf array.  */
+
+gcov_type
+gcov_read_counter_mem (void)
+{
+  gcov_type ret;
+  gcc_assert (gcov_value_buf_pos < gcov_value_buf_size);
+  ret = *(gcov_value_buf + gcov_value_buf_pos);
+  ++gcov_value_buf_pos;
+  return ret;
+}
+
+/* Return the recorded merge weight.  */
+
+unsigned
+gcov_get_merge_weight (void)
+{
+  return gcov_merge_weight;
+}
+
+/* A wrapper function for merge functions. It sets up the
+   value buffer and weights and then calls the merge function.  */
+
+static void
+merge_wrapper (gcov_merge_fn f, gcov_type *v1, gcov_unsigned_t n,
+               gcov_type *v2, unsigned w)
+{
+  gcov_value_buf = v2;
+  gcov_value_buf_pos = 0;
+  gcov_value_buf_size = n;
+  gcov_merge_weight = w;
+  (*f) (v1, n);
+}
+
+/* Offline tool to manipulate profile data.
+   This tool targets on matched profiles. But it has some tolerance on
+   unmatched profiles.
+   When merging p1 to p2 (p2 is the dst),
+   * m.gcda in p1 but not in p2: append m.gcda to p2 with specified weight;
+     emit warning
+   * m.gcda in p2 but not in p1: keep m.gcda in p2 and multiply by
+     specified weight; emit warning.
+   * m.gcda in both p1 and p2:
+   ** p1->m.gcda->f checksum matches p2->m.gcda->f: simple merge.
+   ** p1->m.gcda->f checksum does not matches p2->m.gcda->f: keep
+      p2->m.gcda->f and
+      drop p1->m.gcda->f. A warning is emitted.  */
+
+/* Add INFO2's counter to INFO1, multiplying by weight W.  */
+
+static int
+gcov_merge (struct gcov_info *info1, struct gcov_info *info2, int w)
+{
+  unsigned f_ix;
+  unsigned n_functions = info1->n_functions;
+  int has_mismatch = 0;
+
+  gcc_assert (info2->n_functions == n_functions);
+  for (f_ix = 0; f_ix < n_functions; f_ix++)
+    {
+      unsigned t_ix;
+      const struct gcov_fn_info *gfi_ptr1 = info1->functions[f_ix];
+      const struct gcov_fn_info *gfi_ptr2 = info2->functions[f_ix];
+      const struct gcov_ctr_info *ci_ptr1, *ci_ptr2;
+
+      if (!gfi_ptr1 || gfi_ptr1->key != info1)
+        continue;
+      if (!gfi_ptr2 || gfi_ptr2->key != info2)
+        continue;
+
+      if (gfi_ptr1->cfg_checksum != gfi_ptr2->cfg_checksum)
+        {
+          fprintf (stderr, "in %s, cfg_checksum mismatch, skipping\n",
+                  info1->filename);
+          has_mismatch = 1;
+          continue;
+        }
+      ci_ptr1 = gfi_ptr1->ctrs;
+      ci_ptr2 = gfi_ptr2->ctrs;
+      for (t_ix = 0; t_ix != GCOV_COUNTERS; t_ix++)
+        {
+          gcov_merge_fn merge1 = info1->merge[t_ix];
+          gcov_merge_fn merge2 = info2->merge[t_ix];
+
+          gcc_assert (merge1 == merge2);
+          if (!merge1)
+            continue;
+          gcc_assert (ci_ptr1->num == ci_ptr2->num);
+          merge_wrapper (merge1, ci_ptr1->values, ci_ptr1->num, ci_ptr2->values, w);
+          ci_ptr1++;
+          ci_ptr2++;
+        }
+    }
+
+  return has_mismatch;
+}
+
+/* Find and return the match gcov_info object for INFO from ARRAY.
+   SIZE is the length of ARRAY.
+   Return NULL if there is no match.  */
+
+static struct gcov_info *
+find_match_gcov_info (struct gcov_info **array, int size, struct gcov_info *info)
+{
+  struct gcov_info *gi_ptr;
+  struct gcov_info *ret = NULL;
+  int i;
+
+  for (i = 0; i < size; i++)
+    {
+      gi_ptr = array[i];
+      if (gi_ptr == 0)
+        continue;
+      /* For LIPO, it's easy as we can just match the module_id.  */
+      if (gi_ptr->mod_info && info->mod_info)
+        {   
+          if (gi_ptr->mod_info->ident == info->mod_info->ident)
+            {   
+              ret = gi_ptr;
+              array[i] = 0;
+              break;
+            }   
+        }   
+      else /* For FDO, we have to match the name. This can be expensive.
+              Maybe we should use hash here.  */
+        if (!strcmp (gi_ptr->filename, info->filename))
+          {   
+            ret = gi_ptr;
+            array[i] = 0;
+            break;
+          }   
+    }
+
+  if (ret && ret->n_functions != info->n_functions)
+    {
+      fprintf (stderr, "mismatched profiles in %s (%d functions"
+                       " vs %d functions)\n",
+                       ret->filename,
+                       ret->n_functions,
+                       info->n_functions);
+      ret = NULL;
+    }
+  return ret;
+}
+
+/* Merge the list of gcov_info list from SRC_PROFILE to TGT_PROFILE.
+   Return 0 on success: without mismatch.
+   Reutrn 1 on error.  */
+
+int
+gcov_profile_merge (struct gcov_info *tgt_profile, struct gcov_info *src_profile,
+                    int w1, int w2)
+{
+  struct gcov_info *gi_ptr;
+  struct gcov_info **tgt_infos;
+  struct gcov_info *tgt_tail;
+  struct gcov_info **in_src_not_tgt;
+  unsigned tgt_cnt = 0, src_cnt = 0;
+  unsigned unmatch_info_cnt = 0;
+  unsigned int i;
+
+  for (gi_ptr = tgt_profile; gi_ptr; gi_ptr = gi_ptr->next)
+    tgt_cnt++;
+  for (gi_ptr = src_profile; gi_ptr; gi_ptr = gi_ptr->next)
+    src_cnt++;
+  tgt_infos = (struct gcov_info **) xmalloc (sizeof (struct gcov_info *)
+                 * tgt_cnt);
+  gcc_assert (tgt_infos);
+  in_src_not_tgt = (struct gcov_info **) xmalloc (sizeof (struct gcov_info *)
+                     * src_cnt);
+  gcc_assert (in_src_not_tgt);
+
+  for (gi_ptr = tgt_profile, i = 0; gi_ptr; gi_ptr = gi_ptr->next, i++)
+    tgt_infos[i] = gi_ptr;
+
+  tgt_tail = tgt_infos[tgt_cnt - 1];
+
+  /* First pass on tgt_profile, we multiply w1 to all counters.  */
+  if (w1 > 1)
+    {
+       for (i = 0; i < tgt_cnt; i++)
+         gcov_merge (tgt_infos[i], tgt_infos[i], w1-1);
+    }
+
+  /* Second pass, add src_profile to the tgt_profile.  */
+  for (gi_ptr = src_profile; gi_ptr; gi_ptr = gi_ptr->next)
+    {
+      struct gcov_info *gi_ptr1;
+
+      gi_ptr1 = find_match_gcov_info (tgt_infos, tgt_cnt, gi_ptr);
+      if (gi_ptr1 == NULL)
+        {
+          in_src_not_tgt[unmatch_info_cnt++] = gi_ptr;
+          continue;
+        }
+      gcov_merge (gi_ptr1, gi_ptr, w2);
+    }
+
+  /* For modules in src but not in tgt. We adjust the counter and append.  */
+  for (i = 0; i < unmatch_info_cnt; i++)
+    {
+      gi_ptr = in_src_not_tgt[i];
+      gcov_merge (gi_ptr, gi_ptr, w2 - 1);
+      tgt_tail->next = gi_ptr;
+      tgt_tail = gi_ptr;
+    }
+
+  return 0;
+}
+
+/* This part of code is to scale profile counters.  */
+
+/* Type of function used to normalize counters.  */
+typedef void (*gcov_scale_fn) (gcov_type *, gcov_unsigned_t, double);
+
+/* Scale arc counters. N_COUNTERS of counter value in COUNTERS array are
+   multiplied by a factor F.  */
+
+static void
+__gcov_scale_add (gcov_type *counters, unsigned n_counters, double f)
+{
+  for (; n_counters; counters++, n_counters--)
+    {
+      gcov_type val = *counters;
+      *counters = val * f;
+    }
+}
+
+/* Scale ior counters.  */
+
+static void
+__gcov_scale_ior (gcov_type *counters ATTRIBUTE_UNUSED,
+                      unsigned n_counters ATTRIBUTE_UNUSED,
+                      double f ATTRIBUTE_UNUSED)
+{
+  /* Do nothing.  */
+}
+
+/* Scale delta counters. Multiplied the counters in COUNTERS array
+   by a factor of F.  */
+
+static void
+__gcov_scale_delta (gcov_type *counters, unsigned n_counters, double f)
+{
+  unsigned i, n_measures;
+
+  gcc_assert (!(n_counters % 4));
+  n_measures = n_counters / 4;
+  for (i = 0; i < n_measures; i++, counters += 4)
+    {
+      counters[2] *= f;
+      counters[3] *= f;
+    }
+}
+
+/* Scale single counters. Multiplied the counters in COUNTERS array
+   by a factor of F.  */
+
+static void
+__gcov_scale_single (gcov_type *counters, unsigned n_counters, double f)
+{
+  unsigned i, n_measures;
+
+  gcc_assert (!(n_counters % 3));
+  n_measures = n_counters / 3;
+  for (i = 0; i < n_measures; i++, counters += 3)
+    {
+      counters[1] *= f;
+      counters[2] *= f;
+    }
+}
+
+/* Scale indirect-call profile counters. Multiplied the counters in COUNTERS
+   array by a factor of F.  */
+
+static void
+__gcov_scale_icall_topn (gcov_type *counters, unsigned n_counters, double f)
+{
+  unsigned i;
+
+  gcc_assert (!(n_counters % GCOV_ICALL_TOPN_NCOUNTS));
+  for (i = 0; i < n_counters; i += GCOV_ICALL_TOPN_NCOUNTS)
+    {
+      unsigned j;
+      gcov_type *value_array = &counters[i + 1];
+
+      for (j = 0; j < GCOV_ICALL_TOPN_NCOUNTS - 1; j += 2)
+        value_array[1] *= f;
+    }
+}
+
+/* Scale direct-call profile counters. Multiplied the counters in COUNTERS
+   by a factor of F.  */
+
+static void
+__gcov_scale_dc (gcov_type *counters, unsigned n_counters, double f)
+{
+  unsigned i;
+
+  gcc_assert (!(n_counters % 2));
+  for (i = 0; i < n_counters; i += 2)
+    counters[1] *= f;
+}
+
+/* Scaling functions for counters.  */
+static gcov_scale_fn ctr_scale_functions[GCOV_COUNTERS] = {
+    __gcov_scale_add,
+    __gcov_scale_add,
+    __gcov_scale_add,
+    __gcov_scale_single,
+    __gcov_scale_delta,
+    __gcov_scale_single,
+    __gcov_scale_add,
+    __gcov_scale_ior,
+    __gcov_scale_icall_topn,
+    __gcov_scale_dc,
+};
+
+/* Driver for scaling profile counters.  */
+
+int
+gcov_profile_scale (struct gcov_info *profile, float scale_factor)
+{
+  struct gcov_info *gi_ptr;
+  unsigned f_ix;
+
+  if (verbose)
+    fprintf (stdout, "scale_factor is %f\n", scale_factor);
+
+  /* Scaling the counters.  */
+  for (gi_ptr = profile; gi_ptr; gi_ptr = gi_ptr->next)
+    for (f_ix = 0; f_ix < gi_ptr->n_functions; f_ix++)
+      {
+        unsigned t_ix;
+        const struct gcov_fn_info *gfi_ptr = gi_ptr->functions[f_ix];
+        const struct gcov_ctr_info *ci_ptr;
+
+        if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+          continue;
+
+        ci_ptr = gfi_ptr->ctrs;
+        for (t_ix = 0; t_ix != GCOV_COUNTERS; t_ix++)
+          {
+            gcov_merge_fn merge = gi_ptr->merge[t_ix];
+
+            if (!merge)
+              continue;
+            (*ctr_scale_functions[t_ix]) (ci_ptr->values, ci_ptr->num, scale_factor);
+            ci_ptr++;
+          }
+      }
+
+  return 0;
+}
+
+/* Driver for normalize profile counters.  */
+
+int
+gcov_profile_normalize (struct gcov_info *profile, gcov_type max_val)
+{
+  struct gcov_info *gi_ptr;
+  gcov_type curr_max_val = 0;
+  unsigned f_ix;
+  unsigned int i;
+  float scale_factor;
+
+  /* Find the larest count value.  */
+  for (gi_ptr = profile; gi_ptr; gi_ptr = gi_ptr->next)
+    for (f_ix = 0; f_ix < gi_ptr->n_functions; f_ix++)
+      {
+        unsigned t_ix;
+        const struct gcov_fn_info *gfi_ptr = gi_ptr->functions[f_ix];
+        const struct gcov_ctr_info *ci_ptr;
+
+        if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+          continue;
+
+        ci_ptr = gfi_ptr->ctrs;
+        for (t_ix = 0; t_ix < 1; t_ix++)
+          {
+            for (i = 0; i < ci_ptr->num; i++)
+              if (ci_ptr->values[i] > curr_max_val)
+                curr_max_val = ci_ptr->values[i];
+            ci_ptr++;
+          }
+      }
+
+  scale_factor = (float)max_val / curr_max_val;
+  if (verbose)
+    fprintf (stdout, "max_val is %lld\n", (long long) curr_max_val);
+
+  return gcov_profile_scale (profile, scale_factor);
+}
+
+/* Type of function used to normalize counters.  */
+typedef void (*gcov_scale2_fn) (gcov_type *, gcov_unsigned_t, int, int);
+
+/* Scale2 arc counters.  */
+
+static void
+__gcov_scale2_add (gcov_type *counters, unsigned n_counters, int n, int d)
+{
+  for (; n_counters; counters++, n_counters--)
+    {
+      gcov_type val = *counters;
+      *counters = (val / d) * n;
+    }
+}
+
+/* Scale2 ior counters.  */
+
+static void
+__gcov_scale2_ior (gcov_type *counters ATTRIBUTE_UNUSED,
+                      unsigned n_counters ATTRIBUTE_UNUSED,
+                      int n ATTRIBUTE_UNUSED,
+                      int d ATTRIBUTE_UNUSED)
+{
+  /* do nothing.  */
+}
+
+/* Scale2 delta counters.  */
+
+static void
+__gcov_scale2_delta (gcov_type *counters, unsigned n_counters, int n, int d)
+{
+  unsigned i, n_measures;
+
+  gcc_assert (!(n_counters % 4));
+  n_measures = n_counters / 4;
+  for (i = 0; i < n_measures; i++, counters += 4)
+    {
+      counters[2] = (counters[2] / d) * n;
+      counters[3] = (counters[3] / d) * n;
+    }
+}
+
+/* Scale2 single counters.  */
+
+static void
+__gcov_scale2_single (gcov_type *counters, unsigned n_counters, int n, int d)
+{
+  unsigned i, n_measures;
+
+  gcc_assert (!(n_counters % 3));
+  n_measures = n_counters / 3;
+  for (i = 0; i < n_measures; i++, counters += 3)
+    {
+      counters[1] = (counters[1] / d) * n;
+      counters[2] = (counters[2] / d) * n;
+    }
+}
+
+/* Scale2 indirect-call profile counters. Multiplied the counters in COUNTERS
+   array by a factor of F.  */
+
+static void
+__gcov_scale2_icall_topn (gcov_type *counters, unsigned n_counters, int n, int d)
+{
+  unsigned i;
+
+  gcc_assert (!(n_counters % GCOV_ICALL_TOPN_NCOUNTS));
+  for (i = 0; i < n_counters; i += GCOV_ICALL_TOPN_NCOUNTS)
+    {
+      unsigned j;
+      gcov_type *value_array = &counters[i+1];
+
+      for (j = 0; j < GCOV_ICALL_TOPN_NCOUNTS - 1; j += 2)
+        value_array[j+1] = (value_array[j+1] / d) * n;
+    }
+}
+
+/* Scale2 direct-call profile counters. Multiplied the counters in COUNTERS
+   by a factor of F.  */
+
+static void
+__gcov_scale2_dc (gcov_type *counters, unsigned n_counters, int n, int d)
+{
+  unsigned i;
+
+  gcc_assert (!(n_counters % 2));
+  for (i = 0; i < n_counters; i += 2)
+    counters[i+1] = (counters[i+1] / d) * n;
+}
+
+/* Scale2 functions for counters.  */
+static gcov_scale2_fn ctr_scale2_functions[GCOV_COUNTERS] = {
+    __gcov_scale2_add,
+    __gcov_scale2_add,
+    __gcov_scale2_add,
+    __gcov_scale2_single,
+    __gcov_scale2_delta,
+    __gcov_scale2_single,
+    __gcov_scale2_add,
+    __gcov_scale2_ior,
+    __gcov_scale2_icall_topn,
+    __gcov_scale2_dc,
+};
+
+/* Driver for scale2 profile counters.  */
+
+int
+gcov_profile_scale2 (struct gcov_info *profile, int n, int d)
+{
+  struct gcov_info *gi_ptr;
+  unsigned f_ix;
+
+  if (verbose)
+    fprintf (stdout, "scale_factor is %d/%d\n", n, d);
+
+  gcc_assert (n >= 0 && d > 0);
+
+  /* Scale the counters.  */
+  for (gi_ptr = profile; gi_ptr; gi_ptr = gi_ptr->next)
+    for (f_ix = 0; f_ix < gi_ptr->n_functions; f_ix++)
+      {
+        unsigned t_ix;
+        const struct gcov_fn_info *gfi_ptr = gi_ptr->functions[f_ix];
+        const struct gcov_ctr_info *ci_ptr;
+
+        if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+          continue;
+
+        ci_ptr = gfi_ptr->ctrs;
+        for (t_ix = 0; t_ix != GCOV_COUNTERS; t_ix++)
+          {
+            gcov_merge_fn merge = gi_ptr->merge[t_ix];
+
+            if (!merge)
+              continue;
+            (*ctr_scale2_functions[t_ix]) (ci_ptr->values, ci_ptr->num, n, d);
+            ci_ptr++;
+          }
+      }
+
+  return 0;
+}
+
Index: gcc/params.c
===================================================================
--- gcc/params.c	(revision 206671)
+++ gcc/params.c	(working copy)
@@ -70,7 +70,9 @@  void
 global_init_params (void)
 {
   add_params (lang_independent_params, LAST_PARAM);
+#ifndef IN_GCOV_TOOL
   targetm_common.option_default_params ();
+#endif
 }
 
 /* Note that all parameters have been added and all default values
Index: gcc/coretypes.h
===================================================================
--- gcc/coretypes.h	(revision 206671)
+++ gcc/coretypes.h	(working copy)
@@ -43,6 +43,9 @@  see the files COPYING3 and COPYING.RUNTIME respect
 
 #ifndef USED_FOR_TARGET
 
+typedef HOST_WIDEST_INT gcov_type;
+typedef unsigned HOST_WIDEST_INT gcov_type_unsigned;
+
 struct bitmap_head_def;
 typedef struct bitmap_head_def *bitmap;
 typedef const struct bitmap_head_def *const_bitmap;
Index: gcc/gcov-tool.c
===================================================================
--- gcc/gcov-tool.c	(revision 0)
+++ gcc/gcov-tool.c	(revision 0)
@@ -0,0 +1,603 @@ 
+/* Gcc offline profile processing tool support. */
+/* Compile this one with gcc.  */
+/* Copyright (C) 2014 Free Software Foundation, Inc.
+   Contributed by Rong Xu <xur@google.com>.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "intl.h"
+#include "diagnostic.h"
+#include "version.h"
+#include "gcov-io.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <ftw.h>
+#include <getopt.h>
+#include "params.h"
+
+extern int gcov_profile_merge (struct gcov_info*, struct gcov_info*, int, int);
+extern int gcov_profile_normalize (struct gcov_info*, gcov_type);
+extern int gcov_profile_scale (struct gcov_info*, float);
+extern int gcov_profile_scale2 (struct gcov_info*, int, int);
+extern struct gcov_info* gcov_read_profile_dir (const char*, int);
+extern void gcov_exit (void);
+extern void set_gcov_list (struct gcov_info *);
+extern void gcov_set_verbose (void);
+
+static int verbose;
+
+gcov_unsigned_t __gcov_lipo_grouping_algorithm;
+gcov_unsigned_t __gcov_lipo_merge_modu_edges;
+gcov_unsigned_t __gcov_lipo_weak_inclusion;
+gcov_unsigned_t __gcov_lipo_max_mem;
+gcov_unsigned_t __gcov_lipo_random_group_size;
+gcov_unsigned_t __gcov_lipo_cutoff;
+gcov_unsigned_t __gcov_lipo_random_seed;
+gcov_unsigned_t __gcov_lipo_dump_cgraph;  
+gcov_unsigned_t __gcov_lipo_propagate_scale;
+
+/* Remove file NAME if it has a gcda suffix. */
+
+static int
+unlink_gcda_file (const char *name,
+                  const struct stat *status ATTRIBUTE_UNUSED,
+                  int type ATTRIBUTE_UNUSED,
+                  struct FTW *ftwbuf ATTRIBUTE_UNUSED)
+{
+  int ret = 0;
+  int len = strlen (name);
+  int len1 = strlen (GCOV_DATA_SUFFIX);
+
+  if (len > len1 && !strncmp (len -len1 + name, GCOV_DATA_SUFFIX, len1))
+    remove (name);
+
+  if (ret)
+    {
+      fnotice (stderr, "error in removing %s\n", name);
+      exit (FATAL_EXIT_CODE);
+    }
+
+  return ret;
+}
+
+/* Remove the gcda files in PATH recursively.  */
+
+static int
+unlink_profile_dir (const char *path)
+{
+    return nftw(path, unlink_gcda_file, 64, FTW_DEPTH | FTW_PHYS);
+}
+
+/* Merging profile D1 and D2 with weight as W1 and W2, respectively.
+   The result profile is written to directory OUT.
+   Return 0 on success.  */
+
+static int
+profile_merge (const char *d1, const char *d2, const char *out, int w1, int w2)
+{
+  char *pwd;
+  int ret;
+  struct gcov_info * d1_profile;
+  struct gcov_info * d2_profile;
+
+
+  d1_profile = gcov_read_profile_dir (d1, 0);
+  if (!d1_profile)
+    return 1;
+
+  if (d2)
+    {
+      d2_profile = gcov_read_profile_dir (d2, 0);
+      if (!d2_profile)
+        return 1;
+
+      /* The actual merge: we overwrite to d1_profile.  */
+      ret = gcov_profile_merge (d1_profile, d2_profile, w1, w2);
+
+      if (ret)
+        return ret;
+    }
+
+  /* Output new profile.  */
+  unlink_profile_dir (out);
+  mkdir (out, 0755);
+  pwd = getcwd (NULL, 0);
+  gcc_assert (pwd);
+  ret = chdir (out);
+  gcc_assert (ret == 0);
+
+  set_gcov_list (d1_profile);
+  gcov_exit ();
+
+  ret = chdir (pwd);
+  free (pwd);
+  return 0;
+}
+
+/* Usage message for profile merge.  */
+
+static void
+print_merge_usage_message (int error_p)
+{
+  FILE *file = error_p ? stderr : stdout;
+
+  fnotice (file, "  merge [options] <dir1> <dir2>         Merge coverage file contents\n");
+  fnotice (file, "    -v, --verbose                       Verbose mode\n");
+  fnotice (file, "    -o, --output <dir>                  Output directory\n");
+  fnotice (file, "    -w, --weight <w1,w2>                Set weights (float point values)\n");
+}
+
+static const struct option merge_options[] =
+{
+  { "verbose",                no_argument,       NULL, 'v' },
+  { "output",                 required_argument, NULL, 'o' },
+  { "weight",                 required_argument, NULL, 'w' },
+  { 0, 0, 0, 0 }
+};
+
+/* Print merge usage and exit.  */
+
+static void
+merge_usage (void)
+{
+  fnotice (stderr, "Merge subcomand usage:");
+  print_merge_usage_message (true);
+  exit (FATAL_EXIT_CODE);
+}
+
+/* Driver for profile merge sub-command.  */
+
+static int
+do_merge (int argc, char **argv)
+{
+  int opt;
+  int ret;
+  const char *output_dir = 0;
+  int w1 = 1, w2 = 1;
+
+  optind = 0;
+  while ((opt = getopt_long (argc, argv, "vo:w:", merge_options, NULL)) != -1)
+    {
+      switch (opt)
+        {
+        case 'v':
+          verbose = 1;
+          gcov_set_verbose ();
+          break;
+        case 'o':
+          output_dir = optarg;
+          break;
+        case 'w':
+          sscanf (optarg, "%d,%d", &w1, &w2);
+          if (w1 < 0 || w2 < 0)
+            {
+              fnotice (stderr, "weights need to be non-negative\n");
+              exit (FATAL_EXIT_CODE);
+            }
+          break;
+        default:
+          merge_usage ();
+        }
+    }
+
+  if (output_dir == NULL)
+    output_dir = "merged_profile";
+
+  if (argc - optind == 2)
+    ret = profile_merge (argv[optind], argv[optind+1], output_dir, w1, w2);
+  else
+    merge_usage ();
+
+  return ret;
+}
+
+/* Scale the counters in profile DIR by a factor of N/D.
+   Result is written to dir OUT. Return 0 on success.  */
+
+static int
+profile_rewrite2 (const char *dir, const char *out, int n, int d)
+{
+  char *pwd;
+  int ret;
+  struct gcov_info * profile;
+
+
+  profile = gcov_read_profile_dir (dir, 0);
+  if (!profile)
+    return 1;
+
+  /* Output new profile.  */
+  unlink_profile_dir (out);
+  mkdir (out, 0755);
+  pwd = getcwd (NULL, 0);
+  gcc_assert (pwd);
+  ret = chdir (out);
+  gcc_assert (ret == 0);
+
+  gcov_profile_scale2 (profile, n, d);
+
+  set_gcov_list (profile);
+  gcov_exit ();
+
+  ret = chdir (pwd);
+  free (pwd);
+  return 0;
+}
+
+/* If N_VAL is no-zero, normalize the profile by setting the largest counter
+   counter value to N_VAL and scale others counters proportionally.
+   Otherwise, multiply the all counters by SCALE.  */
+
+static int
+profile_rewrite (const char *d1, const char *out, long long n_val, float scale)
+{
+  char *pwd;
+  int ret;
+  struct gcov_info * d1_profile;
+
+
+  d1_profile = gcov_read_profile_dir (d1, 0);
+  if (!d1_profile)
+    return 1;
+
+  /* Output new profile.  */
+  unlink_profile_dir (out);
+  mkdir (out, 0755);
+  pwd = getcwd (NULL, 0);
+  gcc_assert (pwd);
+  ret = chdir (out);
+  gcc_assert (ret == 0);
+
+  if (n_val)
+    gcov_profile_normalize (d1_profile, (gcov_type) n_val);
+  else
+    gcov_profile_scale (d1_profile, scale);
+
+  set_gcov_list (d1_profile);
+  gcov_exit ();
+
+  ret = chdir (pwd);
+  free (pwd);
+  return 0;
+}
+
+/* Usage function for profile rewrite.  */
+
+static void
+print_rewrite_usage_message (int error_p)
+{
+  FILE *file = error_p ? stderr : stdout;
+
+  fnotice (file, "  rewrite [options] <dir>               Rewrite coverage file contents\n");
+  fnotice (file, "    -v, --verbose                       Verbose mode\n");
+  fnotice (file, "    -o, --output <dir>                  Output directory\n");
+  fnotice (file, "    -s, --scale <float or simple-frac>  Scale the profile counters\n");
+  fnotice (file, "    -n, --normalize <long long>         Normalize the profile\n");
+}
+
+static const struct option rewrite_options[] =
+{
+  { "verbose",                no_argument,       NULL, 'v' },
+  { "output",                 required_argument, NULL, 'o' },
+  { "scale",                  required_argument, NULL, 's' },
+  { "normalize",              required_argument, NULL, 'n' },
+  { 0, 0, 0, 0 }
+};
+
+/* Print profile rewrite usage and exit.  */
+
+static void
+rewrite_usage (void)
+{
+  fnotice (stderr, "Rewrite subcommand usage:");
+  print_rewrite_usage_message (true);
+  exit (FATAL_EXIT_CODE);
+}
+
+/* Driver for profile rewrite sub-command. */
+
+static int
+do_rewrite (int argc, char **argv)
+{
+  int opt;
+  int ret;
+  const char *output_dir = 0;
+  long long normalize_val = 0;
+  float scale = 1.0;
+  int numerator = -1;
+  int denominator = -1;
+
+  optind = 0;
+  while ((opt = getopt_long (argc, argv, "vo:s:n:", rewrite_options, NULL)) != -1)
+    {
+      switch (opt)
+        {
+        case 'v':
+          verbose = 1;
+          gcov_set_verbose ();
+          break;
+        case 'o':
+          output_dir = optarg;
+          break;
+        case 'n':
+          if (scale != 1.0)
+            {
+              fnotice (stderr, "scaling cannot co-exist with normalization\n");
+              scale = 1.0;
+            }
+          normalize_val = atoll (optarg);
+          break;
+        case 's':
+          ret = 0;
+          if (strstr (optarg, "/"))
+            {
+              ret = sscanf (optarg, "%d/%d", &numerator, &denominator);
+              if (ret == 2)
+                {
+                  gcc_assert (numerator >= 0);
+                  gcc_assert (denominator > 0);
+                  scale = 0.0;
+                }
+            }
+          if (ret != 2)
+            {
+              ret = sscanf (optarg, "%f", &scale);
+              gcc_assert (ret == 1);
+            }
+
+          if (scale < 0.0)
+            {
+              fnotice (stderr, "scale needs to be non-negative\n");
+              exit (FATAL_EXIT_CODE);
+            }
+          if (normalize_val != 0)
+            {
+              fnotice (stderr, "normalization cannot co-exist with scaling\n");
+              normalize_val = 0;
+            }
+          break;
+        default:
+          rewrite_usage ();
+        }
+    }
+
+  if (output_dir == NULL)
+    output_dir = "rewrite_profile";
+
+  if (argc - optind == 1)
+    {
+      if (denominator > 0)
+        ret = profile_rewrite2 (argv[optind],  output_dir, numerator, denominator);
+      else
+        ret = profile_rewrite (argv[optind],  output_dir, normalize_val, scale);
+    }
+  else
+    rewrite_usage ();
+
+  return ret;
+}
+
+/* Print a usage message and exit.  If ERROR_P is nonzero, this is an error,
+   otherwise the output of --help.  */
+
+static void
+print_usage (int error_p)
+{
+  FILE *file = error_p ? stderr : stdout;
+  int status = error_p ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE;
+
+  fnotice (file, "Usage: %s [OPTION]... SUB_COMMAND [OPTION]...\n\n", progname);
+  fnotice (file, "Offline tool to handle gcda counts.\n\n");
+  fnotice (file, "  -h, --help                            Print this help, then exit\n");
+  fnotice (file, "  -v, --version                         Print version number, then exit\n");
+  fnotice (file, "  -A, --lipo_algorithm <0|1>            Choose LIPO module grouping algorithm\n"); 
+  fnotice (file, "  -E, --lipo_merge_edge                 Merge module edges in LIPO module grouping\n");
+  fnotice (file, "  -W, --lipo_weak_inclusion             Don't force strict inclusion in grouping\n");
+  fnotice (file, "  -C, --lipo_cutoff <0..100>            Set LIPO module grouping cutoff\n");
+  fnotice (file, "  -M, --lipo_max_memory <int>           Set the max memory in LIPO module grouping\n");
+  fnotice (file, "  -R, --lipo_random_group_size <int>    Set LIPO random grouping size\n");
+  fnotice (file, "  -S, --lipo_random_group_seed <int>    Set LIPO random grouping seed\n");
+  fnotice (file, "  -D, --lipo_dump_cgraph                Dump dynamic call graph\n");
+  fnotice (file, "  -P, --lipo_propagate_scale            Set LIPO propagate scale to true\n");
+  fnotice (file, "\n");
+  print_merge_usage_message (error_p);
+  print_rewrite_usage_message (error_p);
+  fnotice (file, "\nFor bug reporting instructions, please see:\n%s.\n",
+           bug_report_url);
+  exit (status);
+}
+
+/* Print version information and exit.  */
+
+static void
+print_version (void)
+{
+  fnotice (stdout, "%s %s%s\n", progname, pkgversion_string, version_string);
+  fprintf (stdout, "Copyright %s 2014 Free Software Foundation, Inc.\n",
+           _("(C)"));
+  fnotice (stdout,
+           _("This is free software; see the source for copying conditions.\n"
+             "There is NO warranty; not even for MERCHANTABILITY or \n"
+             "FITNESS FOR A PARTICULAR PURPOSE.\n\n"));
+  exit (SUCCESS_EXIT_CODE);
+}
+
+static const struct option options[] =
+{
+  { "help",                   no_argument,       NULL, 'h' },
+  { "version",                no_argument,       NULL, 'v' },
+  { "lipo_algorithm",         required_argument, NULL, 'A' },
+  { "lipo_merge_edge",        no_argument,       NULL, 'E' },
+  { "lipo_weak_inclusion",    no_argument,       NULL, 'W' },
+  { "lipo_cutoff",            required_argument, NULL, 'C' },
+  { "lipo_max_memory",        required_argument, NULL, 'M' },
+  { "lipo_random_group_size", required_argument, NULL, 'R' },
+  { "lipo_random_group_seed", required_argument, NULL, 'S' },
+  { "lipo_dump_cgraph",       no_argument,       NULL, 'D' },
+  { "lipo_propagate_scale",   no_argument,       NULL, 'P' },
+  { 0, 0, 0, 0 }
+};
+
+/* Process args, return index to first non-arg.  */
+
+static int
+process_args (int argc, char **argv)
+{
+  int opt;
+  int ret;
+
+  while ((opt = getopt_long (argc, argv, "+hvA:EWC:M:R:S:DP", options, NULL)) != -1)
+    {
+      switch (opt)
+        {
+        case 'h':
+          print_usage (false);
+          /* Print_usage will exit.  */
+        case 'v':
+          print_version ();
+          /* Print_version will exit.  */
+        case 'E':
+          __gcov_lipo_merge_modu_edges = 1;
+          break;
+        case 'W':
+          __gcov_lipo_weak_inclusion = 1;
+          break;
+        case 'D':
+          __gcov_lipo_dump_cgraph = 1; 
+          break;
+        case 'P':
+          __gcov_lipo_propagate_scale = 1;
+          break;
+        case 'A':
+          sscanf (optarg, "%d", &ret);
+          if (ret != 0 && ret != 1)
+            {
+              fprintf (stderr, "LIPO grouping algorithm can only be 0 or 1. \n");
+              exit (-1);
+            }
+          __gcov_lipo_grouping_algorithm = ret;
+          break;
+        case 'R':
+          sscanf (optarg, "%d", &ret);
+          if (ret < 1)
+            {
+              fprintf (stderr, "LIPO random group size needs to be positive.\n");
+              exit (-1);
+            }
+          __gcov_lipo_random_group_size = ret;
+          break;
+        case 'S':
+          sscanf (optarg, "%d", &ret);
+          __gcov_lipo_random_seed = ret;;
+          break;
+        case 'M':
+          sscanf (optarg, "%d", &ret);
+          if (ret < 0)
+            {
+              fprintf (stderr, "LIPO max-memory size needs to be positive. \n");
+              exit (-1);
+            }
+          __gcov_lipo_max_mem = ret;
+          break;
+        case 'C':
+          sscanf (optarg, "%d", &ret);
+          if (ret < 0 || ret > 100)
+            {
+              fprintf (stderr, "LIPO cutoff value range is [0, 100]. \n");
+              exit (-1);
+            }
+          __gcov_lipo_cutoff = ret;;
+          break;
+        default:
+          print_usage (true);
+          /* Print_usage will exit.  */
+        }
+    }
+
+  return optind;
+}
+
+/* Get the default param value from params.def.  */
+
+#define GET_DEFAULT_PARAM_VALUE(p) compiler_params[p].default_value
+static void
+set_lipo_default_params (void)
+{
+  __gcov_lipo_grouping_algorithm = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_GROUPING_ALGORITHM);
+  __gcov_lipo_merge_modu_edges   = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_MERGE_MODU_EDGES);
+  __gcov_lipo_weak_inclusion     = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_WEAK_INCLUSION);
+  __gcov_lipo_max_mem            = GET_DEFAULT_PARAM_VALUE (PARAM_MAX_LIPO_MEMORY);
+  __gcov_lipo_random_group_size  = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_RANDOM_GROUP_SIZE);
+  __gcov_lipo_cutoff             = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_CUTOFF);
+  __gcov_lipo_random_seed        = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_RANDOM_SEED);
+  __gcov_lipo_dump_cgraph        = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_DUMP_CGRAPH);
+  __gcov_lipo_propagate_scale    = GET_DEFAULT_PARAM_VALUE (PARAM_LIPO_PROPAGATE_SCALE);
+}
+
+/* Main function for gcov-tool.  */
+
+int
+main (int argc, char **argv)
+{
+  const char *p;
+  const char *sub_command;
+
+  p = argv[0] + strlen (argv[0]);
+  while (p != argv[0] && !IS_DIR_SEPARATOR (p[-1]))
+    --p;
+  progname = p;
+
+  xmalloc_set_program_name (progname);
+
+  /* Unlock the stdio streams.  */
+  unlock_std_streams ();
+
+  gcc_init_libintl ();
+
+  diagnostic_initialize (global_dc, 0);
+
+  /* Handle response files.  */
+  expandargv (&argc, &argv);
+
+  /* Register the language-independent parameters.  */
+  global_init_params ();
+  finish_params ();
+  set_lipo_default_params ();
+
+  process_args (argc, argv);
+  if (optind >= argc)
+    print_usage (true);
+
+  sub_command = argv[optind];
+
+  if (!strcmp (sub_command, "merge"))
+    return do_merge (argc - optind, argv + optind);
+  else if (!strcmp (sub_command, "rewrite"))
+    return do_rewrite (argc - optind, argv + optind);
+
+  print_usage (true);
+}
Index: gcc/gcov-io.c
===================================================================
--- gcc/gcov-io.c	(revision 206671)
+++ gcc/gcov-io.c	(working copy)
@@ -555,7 +555,7 @@  gcov_read_counter (void)
    buffer, or NULL on empty string. You must copy the string before
    calling another gcov function.  */
 
-#if !IN_LIBGCOV
+#if !IN_LIBGCOV || IN_GCOV_TOOL
 GCOV_LINKAGE const char *
 gcov_read_string (void)
 {
@@ -632,7 +632,7 @@  gcov_read_summary (struct gcov_summary *summary)
     }
 }
 
-#if !IN_LIBGCOV && IN_GCOV != 1
+#if IN_GCOV_TOOL || !IN_LIBGCOV && IN_GCOV != 1
 /* Read LEN words (unsigned type) and construct MOD_INFO.  */
 
 GCOV_LINKAGE void
@@ -685,7 +685,7 @@  gcov_read_module_info (struct gcov_module_info *mo
 }
 #endif
 
-#if !IN_LIBGCOV
+#if !IN_LIBGCOV || IN_GCOV_TOOL
 /* Reset to a known position.  BASE should have been obtained from
    gcov_position, LENGTH should be a record length.  */
 
Index: gcc/Makefile.in
===================================================================
--- gcc/Makefile.in	(revision 206671)
+++ gcc/Makefile.in	(working copy)
@@ -123,7 +123,8 @@  SUBDIRS =@subdirs@ build
 
 # Selection of languages to be made.
 CONFIG_LANGUAGES = @all_selected_languages@
-LANGUAGES = c gcov$(exeext) gcov-dump$(exeext) $(CONFIG_LANGUAGES)
+LANGUAGES = c gcov$(exeext) gcov-dump$(exeext) gcov-tool$(exeext) \
+            $(CONFIG_LANGUAGES)
 
 # Default values for variables overridden in Makefile fragments.
 # CFLAGS is for the user to override to, e.g., do a cross build with -O2.
@@ -194,6 +195,7 @@  GCC_WARN_CXXFLAGS = $(LOOSE_WARN) $($(@D)-warn) $(
 build/gengtype-lex.o-warn = -Wno-error
 gengtype-lex.o-warn = -Wno-error
 expmed.o-warn = -Wno-error
+libgcov-util.o-warn = -Wno-error
 
 # All warnings have to be shut off in stage1 if the compiler used then
 # isn't gcc; configure determines that.  WARN_CFLAGS will be either
@@ -755,6 +757,7 @@  GCC_TARGET_INSTALL_NAME := $(target_noncanonical)-
 CPP_INSTALL_NAME := $(shell echo cpp|sed '$(program_transform_name)')
 GCOV_INSTALL_NAME := $(shell echo gcov|sed '$(program_transform_name)')
 PROFILE_TOOL_INSTALL_NAME := $(shell echo profile_tool|sed '$(program_transform_name)')
+GCOV_TOOL_INSTALL_NAME := $(shell echo gcov-tool|sed '$(program_transform_name)')
 
 # Setup the testing framework, if you have one
 EXPECT = `if [ -f $${rootme}/../expect/expect ] ; then \
@@ -1480,7 +1483,8 @@  ALL_HOST_FRONTEND_OBJS = $(foreach v,$(CONFIG_LANG
 
 ALL_HOST_BACKEND_OBJS = $(GCC_OBJS) $(OBJS) $(OBJS-libcommon) \
   $(OBJS-libcommon-target) @TREEBROWSER@ main.o c-family/cppspec.o \
-  $(COLLECT2_OBJS) $(EXTRA_GCC_OBJS) $(GCOV_OBJS) $(GCOV_DUMP_OBJS)
+  $(COLLECT2_OBJS) $(EXTRA_GCC_OBJS) $(GCOV_OBJS) $(GCOV_DUMP_OBJS) \
+  $(GCOV_TOOL_OBJS)
 
 # This lists all host object files, whether they are included in this
 # compilation or not.
@@ -1505,6 +1509,7 @@  MOSTLYCLEANFILES = insn-flags.h insn-config.h insn
  $(SPECS) collect2$(exeext) gcc-ar$(exeext) gcc-nm$(exeext) \
  gcc-ranlib$(exeext) \
  gcov-iov$(build_exeext) gcov$(exeext) gcov-dump$(exeext) \
+ gcov-tool$(exeect) \
  gengtype$(exeext) *.[0-9][0-9].* *.[si] *-checksum.c libbackend.a \
  libcommon-target.a libcommon.a libgcc.mk
 
@@ -4070,6 +4075,27 @@  GCOV_DUMP_OBJS = gcov-dump.o vec.o ggc-none.o
 gcov-dump$(exeext): $(GCOV_DUMP_OBJS) $(LIBDEPS)
 	+$(LINKER) $(ALL_LINKERFLAGS) $(LDFLAGS) $(GCOV_DUMP_OBJS) \
 		$(LIBS) -o $@
+
+libgcov-util.o: $(srcdir)/../libgcc/libgcov-util.c gcov-io.c $(GCOV_IO_H) \
+  $(srcdir)/../libgcc/libgcov-driver.c $(srcdir)/../libgcc/libgcov-driver-system.c \
+  $(srcdir)/../libgcc/libgcov-merge.c $(srcdir)/../libgcc/libgcov.h \
+  $(SYSTEM_H) coretypes.h $(TM_H) $(CONFIG_H) version.h intl.h $(DIAGNOSTIC_H)
+	+$(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) -o $@ $<
+dyn-ipa.o: $(srcdir)/../libgcc/dyn-ipa.c gcov-io.c $(srcdir)/../libgcc/libgcov.h \
+   $(GCOV_IO_H) $(SYSTEM_H) coretypes.h \
+   $(TM_H) $(CONFIG_H) version.h intl.h $(DIAGNOSTIC_H)
+	+$(COMPILER) -DIN_GCOV_TOOL -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) \
+	  $(INCLUDES) -o $@ $<
+
+GCOV_TOOL_OBJS = gcov-tool.o libgcov-util.o dyn-ipa.o gcov-params.o
+gcov-tool.o: gcov-tool.c $(GCOV_IO_H) intl.h $(SYSTEM_H) coretypes.h $(TM_H) \
+   $(CONFIG_H) version.h $(DIAGNOSTIC_H)
+gcov_params.o: params.c $(PARAMS_H)
+        +$(COMPILER) -DIN_GCOV_TOOL -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) \
+          $(INCLUDES) -o $@ $<
+gcov-tool$(exeext): $(GCOV_TOOL_OBJS) $(LIBDEPS)
+	+$(LINKER) $(ALL_LINKERFLAGS) $(LDFLAGS) $(GCOV_TOOL_OBJS) \
+	  $(LIBS) -o $@
 #
 # Build the include directories.  The stamp files are stmp-* rather than
 # s-* so that mostlyclean does not force the include directory to
@@ -4697,6 +4723,13 @@  install-common: native lang.install-common install
 	    $(INSTALL_PROGRAM) $(srcdir)/../contrib/profile_tool \
 	    $(DESTDIR)$(bindir)/$(PROFILE_TOOL_INSTALL_NAME)$(exeext); \
 	fi
+# Install gcov-tool if it was compiled.
+	-if [ -f gcov-tool$(exeext) ]; \
+	then \
+	    rm -f $(DESTDIR)$(bindir)/$(GCOV_TOOL_INSTALL_NAME)$(exeext); \
+	    $(INSTALL_PROGRAM) \
+	    gcov-tool$(exeext) $(DESTDIR)$(bindir)/$(GCOV_TOOL_INSTALL_NAME)$(exeext); \
+	fi
 
 # Install the driver program as $(target_noncanonical)-gcc,
 # $(target_noncanonical)-gcc-$(version)