2010-05-11 Silvius Rus <silvius.rus@gmail.com>

	PR libstdc++/43259
	* include/profile/impl/profiler_algos.h: New.
	* include/Makefile.am: Add.
	* include/Makefile.in: Regenerate.
	* include/profile/impl/profiler.h
	(_GLIBCXX_PROFILE_DEFINE_UNINIT_DATA): Add.
	* include/profile/impl/profiler_trace.h
	(__mutex_t, __lock, __unlock): Remove.
	(__lock_object_table, __lock_stack_table): Remove. Replace uses with
	calls to __gnu_cxx::__mutex::lock.
	(__unlock_object_table, __unlock_stack_table): Remove. Replace uses
	with calls to __gnu_cxx::__mutex::unlock.
	(__warn, __cost_factor_writer, __cost_factor_setter): Add.
	* testsuite/ext/profile/profiler_algos.cc: New.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@159268 138bc75d-0d04-0410-961f-82ee72b054a4

6 files changed, 278 insertions, 173 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 61294340d35..903f371fa62 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,20 @@
+2010-05-11  Silvius Rus  <silvius.rus@gmail.com>
+
+	PR libstdc++/43259
+	* include/profile/impl/profiler_algos.h: New.
+	* include/Makefile.am: Add.
+	* include/Makefile.in: Regenerate.
+	* include/profile/impl/profiler.h
+	(_GLIBCXX_PROFILE_DEFINE_UNINIT_DATA): Add.
+	* include/profile/impl/profiler_trace.h
+	(__mutex_t, __lock, __unlock): Remove.
+	(__lock_object_table, __lock_stack_table): Remove. Replace uses with
+	calls to __gnu_cxx::__mutex::lock.
+	(__unlock_object_table, __unlock_stack_table): Remove. Replace uses
+	with calls to __gnu_cxx::__mutex::unlock.
+	(__warn, __cost_factor_writer, __cost_factor_setter): Add.
+	* testsuite/ext/profile/profiler_algos.cc: New.
+
 2010-05-07  Jonathan Wakely  <jwakely.gcc@gmail.com>
 
 	* libsupc++/exception_ptr.h (make_exception_ptr): Add.
diff --git a/libstdc++-v3/include/Makefile.am b/libstdc++-v3/include/Makefile.am
index 23aad14692c..1ced7813c1c 100644
--- a/libstdc++-v3/include/Makefile.am
+++ b/libstdc++-v3/include/Makefile.am
@@ -800,6 +800,7 @@ profile_impl_srcdir = ${glibcxx_srcdir}/include/profile/impl
 profile_impl_builddir = ./profile/impl
 profile_impl_headers = \
 	${profile_impl_srcdir}/profiler.h \
+	${profile_impl_srcdir}/profiler_algos.h \
 	${profile_impl_srcdir}/profiler_container_size.h \
 	${profile_impl_srcdir}/profiler_hash_func.h \
 	${profile_impl_srcdir}/profiler_hashtable_size.h \
diff --git a/libstdc++-v3/include/Makefile.in b/libstdc++-v3/include/Makefile.in
index cf3fa47f616..fd45a43e9da 100644
--- a/libstdc++-v3/include/Makefile.in
+++ b/libstdc++-v3/include/Makefile.in
@@ -1032,6 +1032,7 @@ profile_impl_srcdir = ${glibcxx_srcdir}/include/profile/impl
 profile_impl_builddir = ./profile/impl
 profile_impl_headers = \
 	${profile_impl_srcdir}/profiler.h \
+	${profile_impl_srcdir}/profiler_algos.h \
 	${profile_impl_srcdir}/profiler_container_size.h \
 	${profile_impl_srcdir}/profiler_hash_func.h \
 	${profile_impl_srcdir}/profiler_hashtable_size.h \
diff --git a/libstdc++-v3/include/profile/impl/profiler.h b/libstdc++-v3/include/profile/impl/profiler.h
index b5ac409bb46..07ed50d8e4c 100644
--- a/libstdc++-v3/include/profile/impl/profiler.h
+++ b/libstdc++-v3/include/profile/impl/profiler.h
@@ -44,6 +44,13 @@
 #endif
 
 // Mechanism to define data with inline linkage.
+#define _GLIBCXX_PROFILE_DEFINE_UNINIT_DATA(__type, __name)             \
+  inline __type&                                                        \
+  __get_##__name()                                                      \
+  {                                                                     \
+    static __type __name;                                               \
+    return __name;                                                      \
+  }
 #define _GLIBCXX_PROFILE_DEFINE_DATA(__type, __name, __initial_value...) \
   inline __type& __get_##__name() {                                      \
     static __type __name(__initial_value);                               \
@@ -362,11 +369,6 @@ namespace __gnu_profile
 #define __profcxx_map_to_unordered_map_find(__x...)
 #endif
 
-// Run multithreaded unless instructed not to do so.
-#ifndef _GLIBCXX_PROFILE_NO_THREADS
-#define _GLIBCXX_PROFILE_THREADS
-#endif
-
 // Set default values for compile-time customizable variables.
 #ifndef _GLIBCXX_PROFILE_TRACE_PATH_ROOT
 #define _GLIBCXX_PROFILE_TRACE_PATH_ROOT "libstdcxx-profile"
@@ -389,7 +391,7 @@ namespace __gnu_profile
   "_GLIBCXX_PROFILE_MAX_STACK_DEPTH"
 #endif
 #ifndef _GLIBCXX_PROFILE_MEM_PER_DIAGNOSTIC
-#define _GLIBCXX_PROFILE_MEM_PER_DIAGNOSTIC 2 << 27
+#define _GLIBCXX_PROFILE_MEM_PER_DIAGNOSTIC (1 << 28)
 #endif
 #ifndef _GLIBCXX_PROFILE_MEM_PER_DIAGNOSTIC_ENV_VAR
 #define _GLIBCXX_PROFILE_MEM_PER_DIAGNOSTIC_ENV_VAR \
diff --git a/libstdc++-v3/include/profile/impl/profiler_algos.h b/libstdc++-v3/include/profile/impl/profiler_algos.h
new file mode 100644
index 00000000000..d4de43e9ee0
--- /dev/null
+++ b/libstdc++-v3/include/profile/impl/profiler_algos.h
@@ -0,0 +1,118 @@
+// -*- C++ -*-
+//
+// Copyright (C) 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the terms
+// of the GNU General Public License as published by the Free Software
+// Foundation; either version 2, or (at your option) any later
+// version.
+
+// This library 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 this library; see the file COPYING.  If not, write to
+// the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
+// MA 02111-1307, USA.
+
+// As a special exception, you may use this file as part of a free
+// software library without restriction.  Specifically, if other files
+// instantiate templates or use macros or inline functions from this
+// file, or you compile this file and link it with other files to
+// produce an executable, this file does not by itself cause the
+// resulting executable to be covered by the GNU General Public
+// License.  This exception does not however invalidate any other
+// reasons why the executable file might be covered by the GNU General
+// Public License.
+
+/** @file profile/impl/profiler_algos.h
+ *  @brief Algorithms used by the profile extension.
+ *
+ *  This file is needed to avoid including <algorithm> or <bits/stl_algo.h>.
+ *  Including those files would result in recursive includes.
+ *  These implementations are oversimplified.  In general, efficiency may be
+ *  sacrificed to minimize maintenance overhead.
+ */
+
+#ifndef _GLIBCXX_PROFILE_PROFILER_ALGOS_H
+#define _GLIBCXX_PROFILE_PROFILER_ALGOS_H 1
+
+namespace __gnu_profile
+{
+  /* Helper for __top_n.  Insert in sorted vector, but not beyond Nth elem.  */
+  template<typename _Container>
+    void
+    __insert_top_n(_Container& __output,
+		   const typename _Container::value_type& __value,
+		   typename _Container::size_type __n)
+    {
+      typename _Container::iterator __it = __output.begin();
+      typename _Container::size_type __count = 0;
+
+      // Skip up to N - 1 elements larger than VALUE.
+      // XXX: Could do binary search for random iterators.
+      while (true)
+	{
+	  if (__count >= __n)
+	    // VALUE is not in top N.
+	    return;
+
+	  if (__it == __output.end())
+	    break;
+
+	  if (*__it < __value)
+	    break;
+
+	  ++__it;
+	  ++__count;
+	}
+
+      __output.insert(__it, __value);
+    }
+
+  /* Copy the top N elements in INPUT, sorted in reverse order, to OUTPUT.  */
+  template<typename _Container>
+    void
+    __top_n(const _Container& __input, _Container& __output,
+	    typename _Container::size_type __n)
+    {
+      __output.clear();
+      typename _Container::const_iterator __it;
+      for (__it = __input.begin(); __it != __input.end(); ++__it)
+	__insert_top_n(__output, *__it, __n);
+    }
+
+  /* Simplified clone of std::for_each.  */
+  template<typename _InputIterator, typename _Function>
+    _Function 
+    __for_each(_InputIterator __first, _InputIterator __last, _Function __f)
+    {
+      for (; __first != __last; ++__first)
+	__f(*__first);
+      return __f;
+    }
+
+  /* Simplified clone of std::remove.  */
+  template<typename _ForwardIterator, typename _Tp>
+    _ForwardIterator
+    __remove(_ForwardIterator __first, _ForwardIterator __last,
+	     const _Tp& __value)
+    {
+      if(__first == __last)
+	return __first;
+      _ForwardIterator __result = __first;
+      ++__first;
+      for(; __first != __last; ++__first)
+	if(!(*__first == __value))
+	  {
+	    *__result = *__first;
+	    ++__result;
+	  }
+      return __result;
+    }
+} // namespace __gnu_profile
+
+#endif /* _GLIBCXX_PROFILE_PROFILER_ALGOS_H */
diff --git a/libstdc++-v3/include/profile/impl/profiler_trace.h b/libstdc++-v3/include/profile/impl/profiler_trace.h
index ba486a57d93..bfa8a6c3b21 100644
--- a/libstdc++-v3/include/profile/impl/profiler_trace.h
+++ b/libstdc++-v3/include/profile/impl/profiler_trace.h
@@ -53,43 +53,31 @@
 #define _GLIBCXX_IMPL_UNORDERED_MAP std::tr1::unordered_map
 #endif
 
+#include <ext/concurrence.h>
 #include <fstream>
 #include <string>
 #include <utility>
-#include <bits/stl_heap.h> // for std::make_heap, std::sort_heap
-
-#if (defined _GLIBCXX_PROFILE_THREADS) && !(defined _GLIBCXX_HAVE_TLS)
-#error You do not seem to have TLS support, which is required by the profile \
-  mode.  If your program is not multithreaded, recompile with \
-  -D_GLIBCXX_PROFILE_NO_THREADS
-#endif
-
-#if defined _GLIBCXX_PROFILE_THREADS && defined _GLIBCXX_HAVE_TLS
-#include <pthread.h>
-#endif
+#include <vector>
 
+#include "profile/impl/profiler_algos.h"
 #include "profile/impl/profiler_state.h"
 #include "profile/impl/profiler_node.h"
 
 namespace __gnu_profile
 {
-
-#if defined _GLIBCXX_PROFILE_THREADS && defined _GLIBCXX_HAVE_TLS
-#define _GLIBCXX_IMPL_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
-typedef pthread_mutex_t __mutex_t;
-/** @brief Pthread mutex wrapper.  */
-_GLIBCXX_PROFILE_DEFINE_DATA(__mutex_t, __global_lock, 
-                             PTHREAD_MUTEX_INITIALIZER);
-inline void __lock(__mutex_t& __m) { pthread_mutex_lock(&__m); }
-inline void __unlock(__mutex_t& __m) { pthread_mutex_unlock(&__m); }
-#else
-typedef int __mutex_t;
-/** @brief Mock mutex interface.  */
-#define _GLIBCXX_IMPL_MUTEX_INITIALIZER 0
-_GLIBCXX_PROFILE_DEFINE_DATA(__mutex_t, __global_lock, 0);
-inline void __lock(__mutex_t& __m) {}
-inline void __unlock(__mutex_t& __m) {}
-#endif
+/** @brief Internal environment.  Values can be set one of two ways:
+    1. In config file "var = value".  The default config file path is 
+       libstdcxx-profile.conf.
+    2. By setting process environment variables.  For instance, in a Bash
+       shell you can set the unit cost of iterating through a map like this:
+       export __map_iterate_cost_factor=5.0.
+    If a value is set both in the input file and through an environment
+    variable, the environment value takes precedence.  */
+typedef _GLIBCXX_IMPL_UNORDERED_MAP<std::string, std::string> __env_t;
+_GLIBCXX_PROFILE_DEFINE_UNINIT_DATA(__env_t, __env);
+
+/** @brief Master lock.  */
+_GLIBCXX_PROFILE_DEFINE_UNINIT_DATA(__gnu_cxx::__mutex, __global_lock);
 
 /** @brief Representation of a warning.  */
 struct __warning_data
@@ -98,19 +86,15 @@ struct __warning_data
   __stack_t __context;
   const char* __warning_id;
   const char* __warning_message;
-
   __warning_data()
   : __magnitude(0.0), __context(NULL), __warning_id(NULL),
     __warning_message(NULL) { }
-
   __warning_data(float __m, __stack_t __c, const char* __id, 
                  const char* __msg)
-  : __magnitude(__m), __context(__c), __warning_id(__id),
+  : __magnitude(__m), __context(__c), __warning_id(__id), 
     __warning_message(__msg) { }
-
-  bool
-  operator>(const struct __warning_data& __other) const
-  { return __magnitude > __other.__magnitude; }
+  bool operator<(const struct __warning_data& __other) const
+  { return __magnitude < __other.__magnitude; }
 };
 
 typedef std::_GLIBCXX_STD_PR::vector<__warning_data> __warning_vector_t;
@@ -228,14 +212,9 @@ class __trace_base
   void __write(FILE* f);
   void __collect_warnings(__warning_vector_t& __warnings);
 
-  void __lock_object_table();
-  void __lock_stack_table();
-  void __unlock_object_table();
-  void __unlock_stack_table();
-
  private:
-  __mutex_t __object_table_lock;
-  __mutex_t __stack_table_lock;
+  __gnu_cxx::__mutex __object_table_lock;
+  __gnu_cxx::__mutex __stack_table_lock;
   typedef _GLIBCXX_IMPL_UNORDERED_MAP<__object_t, 
                                       __object_info> __object_table_t;
   typedef _GLIBCXX_IMPL_UNORDERED_MAP<__stack_t, __stack_info, __stack_hash, 
@@ -253,7 +232,7 @@ void __trace_base<__object_info, __stack_info>::__collect_warnings(
     __warning_vector_t& __warnings)
 {
   typename __stack_table_t::iterator __i = __stack_table.begin();
-  for ( ; __i != __stack_table.end(); ++__i )
+  for (; __i != __stack_table.end(); ++__i)
   {
     __warnings.push_back(__warning_data((*__i).second.__magnitude(), 
                                         (*__i).first, 
@@ -263,30 +242,6 @@ void __trace_base<__object_info, __stack_info>::__collect_warnings(
 }
 
 template <typename __object_info, typename __stack_info>
-void __trace_base<__object_info, __stack_info>::__lock_object_table()
-{
-  __lock(this->__object_table_lock);
-}
-
-template <typename __object_info, typename __stack_info>
-void __trace_base<__object_info, __stack_info>::__lock_stack_table()
-{
-  __lock(this->__stack_table_lock);
-}
-
-template <typename __object_info, typename __stack_info>
-void __trace_base<__object_info, __stack_info>::__unlock_object_table()
-{
-  __unlock(this->__object_table_lock);
-}
-
-template <typename __object_info, typename __stack_info>
-void __trace_base<__object_info, __stack_info>::__unlock_stack_table()
-{
-  __unlock(this->__stack_table_lock);
-}
-
-template <typename __object_info, typename __stack_info>
 __trace_base<__object_info, __stack_info>::__trace_base()
 {
   // Do not pick the initial size too large, as we don't know which diagnostics
@@ -295,7 +250,6 @@ __trace_base<__object_info, __stack_info>::__trace_base()
   __stack_table.rehash(10000);
   __stack_table_byte_size = 0;
   __id = NULL;
-  __object_table_lock = __stack_table_lock = _GLIBCXX_IMPL_MUTEX_INITIALIZER;
 }
 
 template <typename __object_info, typename __stack_info>
@@ -304,10 +258,10 @@ void __trace_base<__object_info, __stack_info>::__add_object(
 {
   if (__max_mem() == 0 
       || __object_table.size() * sizeof(__object_info) <= __max_mem()) {
-    __lock_object_table();
+    this->__object_table_lock.lock();
     __object_table.insert(
         typename __object_table_t::value_type(__object, __info));
-    __unlock_object_table();
+    this->__object_table_lock.unlock();
   }
 }
 
@@ -318,14 +272,14 @@ __object_info* __trace_base<__object_info, __stack_info>::__get_object_info(
   // XXX: Revisit this to see if we can decrease mutex spans.
   // Without this mutex, the object table could be rehashed during an
   // insertion on another thread, which could result in a segfault.
-  __lock_object_table();
+  this->__object_table_lock.lock();
   typename __object_table_t::iterator __object_it = 
       __object_table.find(__object);
   if (__object_it == __object_table.end()){
-    __unlock_object_table();
+    this->__object_table_lock.unlock();
     return NULL;
   } else {
-    __unlock_object_table();
+    this->__object_table_lock.unlock();
     return &__object_it->second;
   }
 }
@@ -334,8 +288,8 @@ template <typename __object_info, typename __stack_info>
 void __trace_base<__object_info, __stack_info>::__retire_object(
     __object_t __object)
 {
-  __lock_object_table();
-  __lock_stack_table();
+  this->__object_table_lock.lock();
+  this->__stack_table_lock.lock();
   typename __object_table_t::iterator __object_it =
       __object_table.find(__object);
   if (__object_it != __object_table.end()){
@@ -358,8 +312,8 @@ void __trace_base<__object_info, __stack_info>::__retire_object(
     }
     __object_table.erase(__object);
   }
-  __unlock_stack_table();
-  __unlock_object_table();
+  this->__object_table_lock.unlock();
+  this->__stack_table_lock.unlock();
 }
 
 template <typename __object_info, typename __stack_info>
@@ -408,40 +362,59 @@ inline void __set_max_mem()
       _GLIBCXX_PROFILE_DATA(_S_max_mem));
 }
 
-inline int __log_magnitude(float f)
+inline int __log_magnitude(float __f)
 {
-  const float log_base = 10.0;
-  int result = 0;
-  int sign = 1;
-  if (f < 0) {
-    f = -f;
-    sign = -1;
+  const float __log_base = 10.0;
+  int __result = 0;
+  int __sign = 1;
+  if (__f < 0) {
+    __f = -__f;
+    __sign = -1;
   }
-  while (f > log_base) {
-    ++result;
-    f /= 10.0;
+  while (__f > __log_base) {
+    ++__result;
+    __f /= 10.0;
   }
-  return sign * result;
+  return __sign * __result;
 }
 
-inline FILE* __open_output_file(const char* extension)
+inline FILE* __open_output_file(const char* __extension)
 {
   // The path is made of _S_trace_file_name + "." + extension.
-  size_t root_len = strlen(_GLIBCXX_PROFILE_DATA(_S_trace_file_name));
-  size_t ext_len = strlen(extension);
-  char* file_name = new char[root_len + 1 + ext_len + 1];
-  memcpy(file_name, _GLIBCXX_PROFILE_DATA(_S_trace_file_name), root_len);
-  *(file_name + root_len) = '.';
-  memcpy(file_name + root_len + 1, extension, ext_len + 1);
-  FILE* out_file = fopen(file_name, "w");
-  if (out_file) {
-    return out_file;
+  size_t __root_len = strlen(_GLIBCXX_PROFILE_DATA(_S_trace_file_name));
+  size_t __ext_len = strlen(__extension);
+  char* __file_name = new char[__root_len + 1 + __ext_len + 1];
+  memcpy(__file_name, _GLIBCXX_PROFILE_DATA(_S_trace_file_name),
+	 __root_len);
+  *(__file_name + __root_len) = '.';
+  memcpy(__file_name + __root_len + 1, __extension, __ext_len + 1);
+  FILE* __out_file = fopen(__file_name, "w");
+  if (__out_file) {
+    return __out_file;
   } else {
-    fprintf(stderr, "Could not open trace file '%s'.\n", file_name);
+    fprintf(stderr, "Could not open trace file '%s'.\n", __file_name);
     abort();
   }
 }
 
+struct __warn
+{
+  FILE* __file;
+  __warn(FILE* __f) { __file = __f; }
+
+  void operator() (const __warning_data& __info)
+    {
+      fprintf(__file,  __info.__warning_id);
+      fprintf(__file, ": improvement = %d",
+	      __log_magnitude(__info.__magnitude));
+      fprintf(__file, ": call stack = ");
+      __gnu_profile::__write(__file, __info.__context);
+      fprintf(__file, ": advice = %s\n", __info.__warning_message);
+      free(const_cast<void*>
+	   (reinterpret_cast<const void*>(__info.__warning_message)));
+    }
+};
+
 /** @brief Final report method, registered with @b atexit.
  *
  * This can also be called directly by user code, including signal handlers.
@@ -451,9 +424,9 @@ inline FILE* __open_output_file(const char* extension)
  */
 inline void __report(void)
 {
-  __lock(_GLIBCXX_PROFILE_DATA(__global_lock));
+  _GLIBCXX_PROFILE_DATA(__global_lock).lock();
 
-  __warning_vector_t __warnings;
+  __warning_vector_t __warnings, __top_warnings;
 
   FILE* __raw_file = __open_output_file("raw");
   __trace_vector_size_report(__raw_file, __warnings);
@@ -465,35 +438,17 @@ inline void __report(void)
   __trace_map_to_unordered_map_report(__raw_file, __warnings);
   fclose(__raw_file);
 
-  // Sort data by magnitude.
-  // XXX: instead of sorting, should collect only top N for better performance.
+  // Sort data by magnitude, keeping just top N.
   size_t __cutoff = __min(_GLIBCXX_PROFILE_DATA(_S_max_warn_count),
                           __warnings.size());
-
-  std::make_heap(__warnings.begin(), __warnings.end(),
-		 std::greater<__warning_vector_t::value_type>());
-  std::sort_heap(__warnings.begin(), __warnings.end(),
-		 std::greater<__warning_vector_t::value_type>());
-  __warnings.resize(__cutoff);
+  __top_n(__warnings, __top_warnings, __cutoff);
 
   FILE* __warn_file = __open_output_file("txt");
-
-  for (__warning_vector_t::iterator __it = __warnings.begin();
-       __it != __warnings.end(); ++__it)
-    {
-      fprintf(__warn_file,  __it->__warning_id);
-      fprintf(__warn_file, ": improvement = %d",
-	      __log_magnitude(__it->__magnitude));
-      fprintf(__warn_file, ": call stack = ");
-      __gnu_profile::__write(__warn_file, __it->__context);
-      fprintf(__warn_file, ": advice = %s\n", __it->__warning_message);
-      free(const_cast<void*>(reinterpret_cast<const void*>
-			     (__it->__warning_message)));
-    }
-
+  __for_each(__top_warnings.begin(), __top_warnings.end(),
+             __warn(__warn_file));
   fclose(__warn_file);
 
-  __unlock(_GLIBCXX_PROFILE_DATA(__global_lock));
+  _GLIBCXX_PROFILE_DATA(__global_lock).unlock();
 }
 
 inline void __set_trace_path()
@@ -519,7 +474,8 @@ inline void __set_max_warn_count()
   }
 }
 
-inline void __read_cost_factors()
+inline void
+__read_cost_factors()
 {
   std::string __conf_file_name(_GLIBCXX_PROFILE_DATA(_S_trace_file_name));
   __conf_file_name += ".conf";
@@ -530,52 +486,66 @@ inline void __read_cost_factors()
     {
       std::string __line;
 
-      while (getline(__conf_file, __line))
+      while (std::getline(__conf_file, __line))
 	{
 	  std::string::size_type __i = __line.find_first_not_of(" \t\n\v");
 
-	  if (__line.length() <= 0 || __line[__i] == '#') {
+	  if (__line.length() <= 0 || __line[__i] == '#')
 	    // Skip empty lines or comments.
 	    continue;
-	  }
-
-	  // Trim.
-	  if (__line.begin() != __line.end())
-	    {
-	      // A simple remove operation.
-	      std::string::iterator __first = __line.begin();
-	      std::string::iterator __result = __first;
-	      ++__first;
-	      for(; __first != __line.end(); ++__first)
-		if(!(*__first == ' '))
-		  {
-		    *__result = *__first;
-		    ++__result;
-		  }
-	      __line.erase(__result, __line.end());
-	    }
-	  std::string::size_type __pos = __line.find("=");
-	  std::string __factor_name = __line.substr(0, __pos);
-	  std::string::size_type __end = __line.find_first_of(";\n");
-	  std::string __factor_value = __line.substr(__pos + 1, __end - __pos);
-
-	  setenv(__factor_name.c_str(), __factor_value.c_str(), 0);
-	}
+        }
+
+      // Trim.
+      __line.erase(__remove(__line.begin(), __line.end(), ' '), __line.end());
+      std::string::size_type __pos = __line.find("=");
+      std::string __factor_name = __line.substr(0, __pos);
+      std::string::size_type __end = __line.find_first_of(";\n");
+      std::string __factor_value = __line.substr(__pos + 1, __end - __pos);
+
+      _GLIBCXX_PROFILE_DATA(__env)[__factor_name] = __factor_value;
     }
 }
 
-inline void __write_cost_factors()
+struct __cost_factor_writer
 {
-  FILE* __file = __open_output_file("conf.out");
-
-  for (__decltype(_GLIBCXX_PROFILE_DATA(__cost_factors)->begin()) __it
-	 = _GLIBCXX_PROFILE_DATA(__cost_factors)->begin();
-       __it != _GLIBCXX_PROFILE_DATA(__cost_factors)->end(); ++__it)
-    fprintf(__file, "%s = %f\n", (*__it)->__env_var, (*__it)->__value);
+  FILE* __file;
+  __cost_factor_writer(FILE* __f) : __file(__f) {}
+  void
+  operator() (const __cost_factor* __factor)
+  { fprintf(__file, "%s = %f\n", __factor->__env_var, __factor->__value); }
+};
 
+inline void
+__write_cost_factors()
+{
+  FILE* __file = __open_output_file("conf.out");
+  __for_each(_GLIBCXX_PROFILE_DATA(__cost_factors)->begin(),
+             _GLIBCXX_PROFILE_DATA(__cost_factors)->end(),
+             __cost_factor_writer(__file));
   fclose(__file);
 }
 
+struct __cost_factor_setter
+{
+  void operator() (__cost_factor* __factor)
+    {
+      // Look it up in the process environment first.
+      const char* __env_value = getenv(__factor->__env_var);
+
+      if (!__env_value)
+        {
+          // Look it up in the config file.
+          __env_t::iterator it = _GLIBCXX_PROFILE_DATA(__env).find(
+              __factor->__env_var);
+          if (it != _GLIBCXX_PROFILE_DATA(__env).end())
+            __env_value = (*it).second.c_str();
+        }
+
+      if (__env_value)
+        __factor->__value = atof(__env_value);
+    }
+};
+
 inline void __set_cost_factors()
 {
   _GLIBCXX_PROFILE_DATA(__cost_factors) = new __cost_factor_vector;
@@ -607,18 +577,14 @@ inline void __set_cost_factors()
       &_GLIBCXX_PROFILE_DATA(__umap_find_cost_factor));
   _GLIBCXX_PROFILE_DATA(__cost_factors)->push_back(
       &_GLIBCXX_PROFILE_DATA(__umap_iterate_cost_factor));
-
-  
-  for (__decltype(_GLIBCXX_PROFILE_DATA(__cost_factors)->begin()) __it
-	 = _GLIBCXX_PROFILE_DATA(__cost_factors)->begin();
-       __it != _GLIBCXX_PROFILE_DATA(__cost_factors)->end(); ++__it)
-    if (char* __env_cost_factor = getenv((*__it)->__env_var))
-      (*__it)->__value = atof(__env_cost_factor);
+  __for_each(_GLIBCXX_PROFILE_DATA(__cost_factors)->begin(),
+             _GLIBCXX_PROFILE_DATA(__cost_factors)->end(),
+             __cost_factor_setter());
 }
 
 inline void __profcxx_init_unconditional()
 {
-  __lock(_GLIBCXX_PROFILE_DATA(__global_lock));
+  _GLIBCXX_PROFILE_DATA(__global_lock).lock();
 
   if (__is_invalid()) {
 
@@ -652,7 +618,7 @@ inline void __profcxx_init_unconditional()
     }
   }
 
-  __unlock(_GLIBCXX_PROFILE_DATA(__global_lock));
+  _GLIBCXX_PROFILE_DATA(__global_lock).unlock();
 }
 
 /** @brief This function must be called by each instrumentation point.