kernel/gcov/clang.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2019 Google, Inc.
  * modified from kernel/gcov/gcc_4_7.c
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
  * may be copied, distributed, and modified under those terms.
  *
  * This program 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.
  *
  *
  * LLVM uses profiling data that's deliberately similar to GCC, but has a
  * very different way of exporting that data.  LLVM calls llvm_gcov_init() once
  * per module, and provides a couple of callbacks that we can use to ask for
  * more data.
  *
  * We care about the "writeout" callback, which in turn calls back into
  * compiler-rt/this module to dump all the gathered coverage data to disk:
  *
  *    llvm_gcda_start_file()
  *      llvm_gcda_emit_function()
  *      llvm_gcda_emit_arcs()
  *      llvm_gcda_emit_function()
  *      llvm_gcda_emit_arcs()
  *      [... repeats for each function ...]
  *    llvm_gcda_summary_info()
  *    llvm_gcda_end_file()
  *
  * This design is much more stateless and unstructured than gcc's, and is
  * intended to run at process exit.  This forces us to keep some local state
  * about which module we're dealing with at the moment.  On the other hand, it
  * also means we don't depend as much on how LLVM represents profiling data
  * internally.
  *
  * See LLVM's lib/Transforms/Instrumentation/GCOVProfiling.cpp for more
  * details on how this works, particularly GCOVProfiler::emitProfileArcs(),
  * GCOVProfiler::insertCounterWriteout(), and
  * GCOVProfiler::insertFlush().
  */

 #define pr_fmt(fmt)	"gcov: " fmt

 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/printk.h>
 #include <linux/ratelimit.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include "gcov.h"

 typedef void (*llvm_gcov_callback)(void);

 struct gcov_info {
 	struct list_head head;

 	const char *filename;
 	unsigned int version;
 	u32 checksum;

 	struct list_head functions;
 };

 struct gcov_fn_info {
 	struct list_head head;

 	u32 ident;
 	u32 checksum;
 	u32 cfg_checksum;

 	u32 num_counters;
 	u64 *counters;
 };

 static struct gcov_info *current_info;

 static LIST_HEAD(clang_gcov_list);

 void llvm_gcov_init(llvm_gcov_callback writeout, llvm_gcov_callback flush)
 {
 	struct gcov_info *info = kzalloc(sizeof(*info), GFP_KERNEL);

 	if (!info)
 		return;

 	INIT_LIST_HEAD(&info->head);
 	INIT_LIST_HEAD(&info->functions);

 	mutex_lock(&gcov_lock);

 	list_add_tail(&info->head, &clang_gcov_list);
 	current_info = info;
 	writeout();
 	current_info = NULL;
 	if (gcov_events_enabled)
 		gcov_event(GCOV_ADD, info);

 	mutex_unlock(&gcov_lock);
 }
 EXPORT_SYMBOL(llvm_gcov_init);

 void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum)
 {
 	current_info->filename = orig_filename;
 	current_info->version = version;
 	current_info->checksum = checksum;
 }
 EXPORT_SYMBOL(llvm_gcda_start_file);

 void llvm_gcda_emit_function(u32 ident, u32 func_checksum, u32 cfg_checksum)
 {
 	struct gcov_fn_info *info = kzalloc(sizeof(*info), GFP_KERNEL);

 	if (!info)
 		return;

 	INIT_LIST_HEAD(&info->head);
 	info->ident = ident;
 	info->checksum = func_checksum;
 	info->cfg_checksum = cfg_checksum;
 	list_add_tail(&info->head, &current_info->functions);
 }
 EXPORT_SYMBOL(llvm_gcda_emit_function);

 void llvm_gcda_emit_arcs(u32 num_counters, u64 *counters)
 {
 	struct gcov_fn_info *info = list_last_entry(&current_info->functions,
 			struct gcov_fn_info, head);

 	info->num_counters = num_counters;
 	info->counters = counters;
 }
 EXPORT_SYMBOL(llvm_gcda_emit_arcs);

 void llvm_gcda_summary_info(void)
 {
 }
 EXPORT_SYMBOL(llvm_gcda_summary_info);

 void llvm_gcda_end_file(void)
 {
 }
 EXPORT_SYMBOL(llvm_gcda_end_file);

 /**
  * gcov_info_filename - return info filename
  * @info: profiling data set
  */
 const char *gcov_info_filename(struct gcov_info *info)
 {
 	return info->filename;
 }

 /**
  * gcov_info_version - return info version
  * @info: profiling data set
  */
 unsigned int gcov_info_version(struct gcov_info *info)
 {
 	return info->version;
 }

 /**
  * gcov_info_next - return next profiling data set
  * @info: profiling data set
  *
  * Returns next gcov_info following @info or first gcov_info in the chain if
  * @info is %NULL.
  */
 struct gcov_info *gcov_info_next(struct gcov_info *info)
 {
 	if (!info)
 		return list_first_entry_or_null(&clang_gcov_list,
 				struct gcov_info, head);
 	if (list_is_last(&info->head, &clang_gcov_list))
 		return NULL;
 	return list_next_entry(info, head);
 }

 /**
  * gcov_info_link - link/add profiling data set to the list
  * @info: profiling data set
  */
 void gcov_info_link(struct gcov_info *info)
 {
 	list_add_tail(&info->head, &clang_gcov_list);
 }

 /**
  * gcov_info_unlink - unlink/remove profiling data set from the list
  * @prev: previous profiling data set
  * @info: profiling data set
  */
 void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info)
 {
 	/* Generic code unlinks while iterating. */
 	__list_del_entry(&info->head);
 }

 /**
  * gcov_info_within_module - check if a profiling data set belongs to a module
  * @info: profiling data set
  * @mod: module
  *
  * Returns true if profiling data belongs module, false otherwise.
  */
 bool gcov_info_within_module(struct gcov_info *info, struct module *mod)
 {
 	return within_module((unsigned long)info->filename, mod);
 }

 /* Symbolic links to be created for each profiling data file. */
 const struct gcov_link gcov_link[] = {
 	{ OBJ_TREE, "gcno" },	/* Link to .gcno file in $(objtree). */
 	{ 0, NULL},
 };

 /**
  * gcov_info_reset - reset profiling data to zero
  * @info: profiling data set
  */
 void gcov_info_reset(struct gcov_info *info)
 {
 	struct gcov_fn_info *fn;

 	list_for_each_entry(fn, &info->functions, head)
 		memset(fn->counters, 0,
 				sizeof(fn->counters[0]) * fn->num_counters);
 }

 /**
  * gcov_info_is_compatible - check if profiling data can be added
  * @info1: first profiling data set
  * @info2: second profiling data set
  *
  * Returns non-zero if profiling data can be added, zero otherwise.
  */
 int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2)
 {
 	struct gcov_fn_info *fn_ptr1 = list_first_entry_or_null(
 			&info1->functions, struct gcov_fn_info, head);
 	struct gcov_fn_info *fn_ptr2 = list_first_entry_or_null(
 			&info2->functions, struct gcov_fn_info, head);

 	if (info1->checksum != info2->checksum)
 		return false;
 	if (!fn_ptr1)
 		return fn_ptr1 == fn_ptr2;
 	while (!list_is_last(&fn_ptr1->head, &info1->functions) &&
 		!list_is_last(&fn_ptr2->head, &info2->functions)) {
 		if (fn_ptr1->checksum != fn_ptr2->checksum)
 			return false;
 		if (fn_ptr1->cfg_checksum != fn_ptr2->cfg_checksum)
 			return false;
 		fn_ptr1 = list_next_entry(fn_ptr1, head);
 		fn_ptr2 = list_next_entry(fn_ptr2, head);
 	}
 	return list_is_last(&fn_ptr1->head, &info1->functions) &&
 		list_is_last(&fn_ptr2->head, &info2->functions);
 }

 /**
  * gcov_info_add - add up profiling data
  * @dest: profiling data set to which data is added
  * @source: profiling data set which is added
  *
  * Adds profiling counts of @source to @dest.
  */
 void gcov_info_add(struct gcov_info *dst, struct gcov_info *src)
 {
 	struct gcov_fn_info *dfn_ptr;
 	struct gcov_fn_info *sfn_ptr = list_first_entry_or_null(&src->functions,
 			struct gcov_fn_info, head);

 	list_for_each_entry(dfn_ptr, &dst->functions, head) {
 		u32 i;

 		for (i = 0; i < sfn_ptr->num_counters; i++)
 			dfn_ptr->counters[i] += sfn_ptr->counters[i];

 		sfn_ptr = list_next_entry(sfn_ptr, head);
 	}
 }

 static struct gcov_fn_info *gcov_fn_info_dup(struct gcov_fn_info *fn)
 {
 	size_t cv_size; /* counter values size */
 	struct gcov_fn_info *fn_dup = kmemdup(fn, sizeof(*fn),
 			GFP_KERNEL);
 	if (!fn_dup)
 		return NULL;
 	INIT_LIST_HEAD(&fn_dup->head);

 	cv_size = fn->num_counters * sizeof(fn->counters[0]);
 	fn_dup->counters = kvmalloc(cv_size, GFP_KERNEL);
 	if (!fn_dup->counters) {
 		kfree(fn_dup);
 		return NULL;
 	}

 	memcpy(fn_dup->counters, fn->counters, cv_size);

 	return fn_dup;
 }

 /**
  * gcov_info_dup - duplicate profiling data set
  * @info: profiling data set to duplicate
  *
  * Return newly allocated duplicate on success, %NULL on error.
  */
 struct gcov_info *gcov_info_dup(struct gcov_info *info)
 {
 	struct gcov_info *dup;
 	struct gcov_fn_info *fn;

 	dup = kmemdup(info, sizeof(*dup), GFP_KERNEL);
 	if (!dup)
 		return NULL;
 	INIT_LIST_HEAD(&dup->head);
 	INIT_LIST_HEAD(&dup->functions);
 	dup->filename = kstrdup(info->filename, GFP_KERNEL);
 	if (!dup->filename)
 		goto err;

 	list_for_each_entry(fn, &info->functions, head) {
 		struct gcov_fn_info *fn_dup = gcov_fn_info_dup(fn);

 		if (!fn_dup)
 			goto err;
 		list_add_tail(&fn_dup->head, &dup->functions);
 	}

 	return dup;

 err:
 	gcov_info_free(dup);
 	return NULL;
 }

 /**
  * gcov_info_free - release memory for profiling data set duplicate
  * @info: profiling data set duplicate to free
  */
 void gcov_info_free(struct gcov_info *info)
 {
 	struct gcov_fn_info *fn, *tmp;

 	list_for_each_entry_safe(fn, tmp, &info->functions, head) {
 		kvfree(fn->counters);
 		list_del(&fn->head);
 		kfree(fn);
 	}
 	kfree(info->filename);
 	kfree(info);
 }

 /**
  * convert_to_gcda - convert profiling data set to gcda file format
  * @buffer: the buffer to store file data or %NULL if no data should be stored
  * @info: profiling data set to be converted
  *
  * Returns the number of bytes that were/would have been stored into the buffer.
  */
 size_t convert_to_gcda(char *buffer, struct gcov_info *info)
 {
 	struct gcov_fn_info *fi_ptr;
 	size_t pos = 0;

 	/* File header. */
 	pos += store_gcov_u32(buffer, pos, GCOV_DATA_MAGIC);
 	pos += store_gcov_u32(buffer, pos, info->version);
 	pos += store_gcov_u32(buffer, pos, info->checksum);

 	list_for_each_entry(fi_ptr, &info->functions, head) {
 		u32 i;

 		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);
 		pos += store_gcov_u32(buffer, pos, 3);
 		pos += store_gcov_u32(buffer, pos, fi_ptr->ident);
 		pos += store_gcov_u32(buffer, pos, fi_ptr->checksum);
 		pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);
 		pos += store_gcov_u32(buffer, pos, GCOV_TAG_COUNTER_BASE);
 		pos += store_gcov_u32(buffer, pos, fi_ptr->num_counters * 2);
 		for (i = 0; i < fi_ptr->num_counters; i++)
 			pos += store_gcov_u64(buffer, pos, fi_ptr->counters[i]);
 	}

 	return pos;
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Copyright (C) 2019 Google, Inc.
	* modified from kernel/gcov/gcc_4_7.c
	*
	* This software is licensed under the terms of the GNU General Public
	* License version 2, as published by the Free Software Foundation, and
	* may be copied, distributed, and modified under those terms.
	*
	* This program 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.
	*
	*
	* LLVM uses profiling data that's deliberately similar to GCC, but has a
	* very different way of exporting that data. LLVM calls llvm_gcov_init() once
	* per module, and provides a couple of callbacks that we can use to ask for
	* more data.
	*
	* We care about the "writeout" callback, which in turn calls back into
	* compiler-rt/this module to dump all the gathered coverage data to disk:
	*
	* llvm_gcda_start_file()
	* llvm_gcda_emit_function()
	* llvm_gcda_emit_arcs()
	* llvm_gcda_emit_function()
	* llvm_gcda_emit_arcs()
	* [... repeats for each function ...]
	* llvm_gcda_summary_info()
	* llvm_gcda_end_file()
	*
	* This design is much more stateless and unstructured than gcc's, and is
	* intended to run at process exit. This forces us to keep some local state
	* about which module we're dealing with at the moment. On the other hand, it
	* also means we don't depend as much on how LLVM represents profiling data
	* internally.
	*
	* See LLVM's lib/Transforms/Instrumentation/GCOVProfiling.cpp for more
	* details on how this works, particularly GCOVProfiler::emitProfileArcs(),
	* GCOVProfiler::insertCounterWriteout(), and
	* GCOVProfiler::insertFlush().
	*/

	#define pr_fmt(fmt) "gcov: " fmt

	#include <linux/kernel.h>
	#include <linux/list.h>
	#include <linux/printk.h>
	#include <linux/ratelimit.h>
	#include <linux/slab.h>
	#include <linux/mm.h>
	#include "gcov.h"

	typedef void (*llvm_gcov_callback)(void);

	struct gcov_info {
	struct list_head head;

	const char *filename;
	unsigned int version;
	u32 checksum;

	struct list_head functions;
	};

	struct gcov_fn_info {
	struct list_head head;

	u32 ident;
	u32 checksum;
	u32 cfg_checksum;

	u32 num_counters;
	u64 *counters;
	};

	static struct gcov_info *current_info;

	static LIST_HEAD(clang_gcov_list);

	void llvm_gcov_init(llvm_gcov_callback writeout, llvm_gcov_callback flush)
	{
	struct gcov_info info = kzalloc(sizeof(info), GFP_KERNEL);

	if (!info)
	return;

	INIT_LIST_HEAD(&info->head);
	INIT_LIST_HEAD(&info->functions);

	mutex_lock(&gcov_lock);

	list_add_tail(&info->head, &clang_gcov_list);
	current_info = info;
	writeout();
	current_info = NULL;
	if (gcov_events_enabled)
	gcov_event(GCOV_ADD, info);

	mutex_unlock(&gcov_lock);
	}
	EXPORT_SYMBOL(llvm_gcov_init);

	void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum)
	{
	current_info->filename = orig_filename;
	current_info->version = version;
	current_info->checksum = checksum;
	}
	EXPORT_SYMBOL(llvm_gcda_start_file);

	void llvm_gcda_emit_function(u32 ident, u32 func_checksum, u32 cfg_checksum)
	{
	struct gcov_fn_info info = kzalloc(sizeof(info), GFP_KERNEL);

	if (!info)
	return;

	INIT_LIST_HEAD(&info->head);
	info->ident = ident;
	info->checksum = func_checksum;
	info->cfg_checksum = cfg_checksum;
	list_add_tail(&info->head, &current_info->functions);
	}
	EXPORT_SYMBOL(llvm_gcda_emit_function);

	void llvm_gcda_emit_arcs(u32 num_counters, u64 *counters)
	{
	struct gcov_fn_info *info = list_last_entry(&current_info->functions,
	struct gcov_fn_info, head);

	info->num_counters = num_counters;
	info->counters = counters;
	}
	EXPORT_SYMBOL(llvm_gcda_emit_arcs);

	void llvm_gcda_summary_info(void)
	{
	}
	EXPORT_SYMBOL(llvm_gcda_summary_info);

	void llvm_gcda_end_file(void)
	{
	}
	EXPORT_SYMBOL(llvm_gcda_end_file);

	/**
	* gcov_info_filename - return info filename
	* @info: profiling data set
	*/
	const char gcov_info_filename(struct gcov_info info)
	{
	return info->filename;
	}

	/**
	* gcov_info_version - return info version
	* @info: profiling data set
	*/
	unsigned int gcov_info_version(struct gcov_info *info)
	{
	return info->version;
	}

	/**
	* gcov_info_next - return next profiling data set
	* @info: profiling data set
	*
	* Returns next gcov_info following @info or first gcov_info in the chain if
	* @info is %NULL.
	*/
	struct gcov_info gcov_info_next(struct gcov_info info)
	{
	if (!info)
	return list_first_entry_or_null(&clang_gcov_list,
	struct gcov_info, head);
	if (list_is_last(&info->head, &clang_gcov_list))
	return NULL;
	return list_next_entry(info, head);
	}

	/**
	* gcov_info_link - link/add profiling data set to the list
	* @info: profiling data set
	*/
	void gcov_info_link(struct gcov_info *info)
	{
	list_add_tail(&info->head, &clang_gcov_list);
	}

	/**
	* gcov_info_unlink - unlink/remove profiling data set from the list
	* @prev: previous profiling data set
	* @info: profiling data set
	*/
	void gcov_info_unlink(struct gcov_info prev, struct gcov_info info)
	{
	/* Generic code unlinks while iterating. */
	__list_del_entry(&info->head);
	}

	/**
	* gcov_info_within_module - check if a profiling data set belongs to a module
	* @info: profiling data set
	* @mod: module
	*
	* Returns true if profiling data belongs module, false otherwise.
	*/
	bool gcov_info_within_module(struct gcov_info info, struct module mod)
	{
	return within_module((unsigned long)info->filename, mod);
	}

	/* Symbolic links to be created for each profiling data file. */
	const struct gcov_link gcov_link[] = {
	{ OBJ_TREE, "gcno" }, /* Link to .gcno file in $(objtree). */
	{ 0, NULL},
	};

	/**
	* gcov_info_reset - reset profiling data to zero
	* @info: profiling data set
	*/
	void gcov_info_reset(struct gcov_info *info)
	{
	struct gcov_fn_info *fn;

	list_for_each_entry(fn, &info->functions, head)
	memset(fn->counters, 0,
	sizeof(fn->counters[0]) * fn->num_counters);
	}

	/**
	* gcov_info_is_compatible - check if profiling data can be added
	* @info1: first profiling data set
	* @info2: second profiling data set
	*
	* Returns non-zero if profiling data can be added, zero otherwise.
	*/
	int gcov_info_is_compatible(struct gcov_info info1, struct gcov_info info2)
	{
	struct gcov_fn_info *fn_ptr1 = list_first_entry_or_null(
	&info1->functions, struct gcov_fn_info, head);
	struct gcov_fn_info *fn_ptr2 = list_first_entry_or_null(
	&info2->functions, struct gcov_fn_info, head);

	if (info1->checksum != info2->checksum)
	return false;
	if (!fn_ptr1)
	return fn_ptr1 == fn_ptr2;
	while (!list_is_last(&fn_ptr1->head, &info1->functions) &&
	!list_is_last(&fn_ptr2->head, &info2->functions)) {
	if (fn_ptr1->checksum != fn_ptr2->checksum)
	return false;
	if (fn_ptr1->cfg_checksum != fn_ptr2->cfg_checksum)
	return false;
	fn_ptr1 = list_next_entry(fn_ptr1, head);
	fn_ptr2 = list_next_entry(fn_ptr2, head);
	}
	return list_is_last(&fn_ptr1->head, &info1->functions) &&
	list_is_last(&fn_ptr2->head, &info2->functions);
	}

	/**
	* gcov_info_add - add up profiling data
	* @dest: profiling data set to which data is added
	* @source: profiling data set which is added
	*
	* Adds profiling counts of @source to @dest.
	*/
	void gcov_info_add(struct gcov_info dst, struct gcov_info src)
	{
	struct gcov_fn_info *dfn_ptr;
	struct gcov_fn_info *sfn_ptr = list_first_entry_or_null(&src->functions,
	struct gcov_fn_info, head);

	list_for_each_entry(dfn_ptr, &dst->functions, head) {
	u32 i;

	for (i = 0; i < sfn_ptr->num_counters; i++)
	dfn_ptr->counters[i] += sfn_ptr->counters[i];

	sfn_ptr = list_next_entry(sfn_ptr, head);
	}
	}

	static struct gcov_fn_info gcov_fn_info_dup(struct gcov_fn_info fn)
	{
	size_t cv_size; /* counter values size */
	struct gcov_fn_info fn_dup = kmemdup(fn, sizeof(fn),
	GFP_KERNEL);
	if (!fn_dup)
	return NULL;
	INIT_LIST_HEAD(&fn_dup->head);

	cv_size = fn->num_counters * sizeof(fn->counters[0]);
	fn_dup->counters = kvmalloc(cv_size, GFP_KERNEL);
	if (!fn_dup->counters) {
	kfree(fn_dup);
	return NULL;
	}

	memcpy(fn_dup->counters, fn->counters, cv_size);

	return fn_dup;
	}

	/**
	* gcov_info_dup - duplicate profiling data set
	* @info: profiling data set to duplicate
	*
	* Return newly allocated duplicate on success, %NULL on error.
	*/
	struct gcov_info gcov_info_dup(struct gcov_info info)
	{
	struct gcov_info *dup;
	struct gcov_fn_info *fn;

	dup = kmemdup(info, sizeof(*dup), GFP_KERNEL);
	if (!dup)
	return NULL;
	INIT_LIST_HEAD(&dup->head);
	INIT_LIST_HEAD(&dup->functions);
	dup->filename = kstrdup(info->filename, GFP_KERNEL);
	if (!dup->filename)
	goto err;

	list_for_each_entry(fn, &info->functions, head) {
	struct gcov_fn_info *fn_dup = gcov_fn_info_dup(fn);

	if (!fn_dup)
	goto err;
	list_add_tail(&fn_dup->head, &dup->functions);
	}

	return dup;

	err:
	gcov_info_free(dup);
	return NULL;
	}

	/**
	* gcov_info_free - release memory for profiling data set duplicate
	* @info: profiling data set duplicate to free
	*/
	void gcov_info_free(struct gcov_info *info)
	{
	struct gcov_fn_info fn, tmp;

	list_for_each_entry_safe(fn, tmp, &info->functions, head) {
	kvfree(fn->counters);
	list_del(&fn->head);
	kfree(fn);
	}
	kfree(info->filename);
	kfree(info);
	}

	/**
	* convert_to_gcda - convert profiling data set to gcda file format
	* @buffer: the buffer to store file data or %NULL if no data should be stored
	* @info: profiling data set to be converted
	*
	* Returns the number of bytes that were/would have been stored into the buffer.
	*/
	size_t convert_to_gcda(char buffer, struct gcov_info info)
	{
	struct gcov_fn_info *fi_ptr;
	size_t pos = 0;

	/* File header. */
	pos += store_gcov_u32(buffer, pos, GCOV_DATA_MAGIC);
	pos += store_gcov_u32(buffer, pos, info->version);
	pos += store_gcov_u32(buffer, pos, info->checksum);

	list_for_each_entry(fi_ptr, &info->functions, head) {
	u32 i;

	pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);
	pos += store_gcov_u32(buffer, pos, 3);
	pos += store_gcov_u32(buffer, pos, fi_ptr->ident);
	pos += store_gcov_u32(buffer, pos, fi_ptr->checksum);
	pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);
	pos += store_gcov_u32(buffer, pos, GCOV_TAG_COUNTER_BASE);
	pos += store_gcov_u32(buffer, pos, fi_ptr->num_counters * 2);
	for (i = 0; i < fi_ptr->num_counters; i++)
	pos += store_gcov_u64(buffer, pos, fi_ptr->counters[i]);
	}

	return pos;
	}