Index: cfe/trunk/CMakeLists.txt
===================================================================
--- cfe/trunk/CMakeLists.txt
+++ cfe/trunk/CMakeLists.txt
@@ -570,6 +570,7 @@
       ARGS ${LLVM_LIT_EXTRA_ARGS}
       )
   endif()
+  add_subdirectory(utils/perf-training)
 endif()
 
 option(CLANG_INCLUDE_DOCS "Generate build targets for the Clang docs."
Index: cfe/trunk/utils/perf-training/CMakeLists.txt
===================================================================
--- cfe/trunk/utils/perf-training/CMakeLists.txt
+++ cfe/trunk/utils/perf-training/CMakeLists.txt
@@ -0,0 +1,36 @@
+if(LLVM_BUILD_INSTRUMENTED)
+  if (CMAKE_CFG_INTDIR STREQUAL ".")
+    set(LLVM_BUILD_MODE ".")
+  else ()
+    set(LLVM_BUILD_MODE "%(build_mode)s")
+  endif ()
+
+  string(REPLACE ${CMAKE_CFG_INTDIR} ${LLVM_BUILD_MODE} CLANG_TOOLS_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
+
+  configure_lit_site_cfg(
+    ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
+    ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
+    )
+
+  add_lit_testsuite(generate-profraw "Generating clang PGO data"
+    ${CMAKE_CURRENT_BINARY_DIR}
+    DEPENDS clang clear-profraw
+    )
+
+  add_custom_target(clear-profraw
+    COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py clean ${CMAKE_CURRENT_BINARY_DIR}
+    COMMENT "Clearing old profraw data")
+
+  if(NOT LLVM_PROFDATA)
+    find_program(LLVM_PROFDATA llvm-profdata)
+  endif()
+
+  if(NOT LLVM_PROFDATA)
+    message(FATAL_ERROR "Must set LLVM_PROFDATA to point to llvm-profdata to use for merging PGO data")
+  endif()
+
+  add_custom_target(generate-profdata
+    COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py merge ${LLVM_PROFDATA} ${CMAKE_CURRENT_BINARY_DIR}/clang.profdata ${CMAKE_CURRENT_BINARY_DIR}
+    COMMENT "Merging profdata"
+    DEPENDS generate-profraw)
+endif()
Index: cfe/trunk/utils/perf-training/README.txt
===================================================================
--- cfe/trunk/utils/perf-training/README.txt
+++ cfe/trunk/utils/perf-training/README.txt
@@ -0,0 +1,6 @@
+==========================
+ Performance Training Data
+==========================
+
+This directory contains simple source files for use as training data for
+generating PGO data and linker order files for clang.
Index: cfe/trunk/utils/perf-training/cxx/hello_world.cpp
===================================================================
--- cfe/trunk/utils/perf-training/cxx/hello_world.cpp
+++ cfe/trunk/utils/perf-training/cxx/hello_world.cpp
@@ -0,0 +1,7 @@
+// RUN: %clang_cpp -c %s
+#include <iostream>
+
+int main(int, char**) {
+  std::cout << "Hello, World!";
+  return 0;
+}
Index: cfe/trunk/utils/perf-training/lit.cfg
===================================================================
--- cfe/trunk/utils/perf-training/lit.cfg
+++ cfe/trunk/utils/perf-training/lit.cfg
@@ -0,0 +1,35 @@
+# -*- Python -*-
+
+from lit import Test
+import lit.formats
+import lit.util
+
+def getSysrootFlagsOnDarwin(config, lit_config):
+    # On Darwin, support relocatable SDKs by providing Clang with a
+    # default system root path.
+    if 'darwin' in config.target_triple:
+        try:
+            out = lit.util.capture(['xcrun', '--show-sdk-path']).strip()
+            res = 0
+        except OSError:
+            res = -1
+        if res == 0 and out:
+            sdk_path = out
+            lit_config.note('using SDKROOT: %r' % sdk_path)
+            return '-isysroot %s' % sdk_path
+    return ''
+
+sysroot_flags = getSysrootFlagsOnDarwin(config, lit_config)
+
+config.clang = lit.util.which('clang', config.clang_tools_dir).replace('\\', '/')
+
+config.name = 'Clang Perf Training'
+config.suffixes = ['.c', '.cpp', '.m', '.mm', '.cu', '.ll', '.cl', '.s', '.S', '.modulemap']
+
+use_lit_shell = os.environ.get("LIT_USE_INTERNAL_SHELL")
+config.test_format = lit.formats.ShTest(use_lit_shell == "0")
+config.substitutions.append( ('%clang_cpp', ' %s --driver-mode=cpp %s ' % (config.clang, sysroot_flags)))
+config.substitutions.append( ('%clang', ' %s %s ' % (config.clang, sysroot_flags) ) )
+
+config.environment['LLVM_PROFILE_FILE'] = 'perf-training-%p.profraw'
+
Index: cfe/trunk/utils/perf-training/lit.site.cfg.in
===================================================================
--- cfe/trunk/utils/perf-training/lit.site.cfg.in
+++ cfe/trunk/utils/perf-training/lit.site.cfg.in
@@ -0,0 +1,20 @@
+import sys
+
+## Autogenerated by LLVM/Clang configuration.
+# Do not edit!
+config.clang_tools_dir = "@CLANG_TOOLS_DIR@"
+config.test_exec_root = "@CMAKE_CURRENT_BINARY_DIR@"
+config.test_source_root = "@CMAKE_CURRENT_SOURCE_DIR@"
+config.target_triple = "@TARGET_TRIPLE@"
+
+# Support substitution of the tools and libs dirs with user parameters. This is
+# used when we can't determine the tool dir at configuration time.
+try:
+    config.clang_tools_dir = config.clang_tools_dir % lit_config.params
+except KeyError:
+    e = sys.exc_info()[1]
+    key, = e.args
+    lit_config.fatal("unable to find %r parameter, use '--param=%s=VALUE'" % (key,key))
+
+# Let the main config do the real work.
+lit_config.load_config(config, "@CLANG_SOURCE_DIR@/utils/perf-training/lit.cfg")
Index: cfe/trunk/utils/perf-training/perf-helper.py
===================================================================
--- cfe/trunk/utils/perf-training/perf-helper.py
+++ cfe/trunk/utils/perf-training/perf-helper.py
@@ -0,0 +1,46 @@
+#===- perf-helper.py - Clang Python Bindings -----------------*- python -*--===#
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+#===------------------------------------------------------------------------===#
+
+import sys
+import os
+import subprocess
+
+def findProfrawFiles(path):
+  profraw_files = []
+  for root, dirs, files in os.walk(path): 
+    for filename in files:
+      if filename.endswith(".profraw"):
+        profraw_files.append(os.path.join(root, filename))
+  return profraw_files
+
+def clean(args):
+  if len(args) != 1:
+    print 'Usage: %s clean <path>\n\tRemoves all *.profraw files from <path>.' % __file__
+    return 1
+  for profraw in findProfrawFiles(args[0]):
+    os.remove(profraw)
+  return 0
+
+def merge(args):
+  if len(args) != 3:
+    print 'Usage: %s clean <llvm-profdata> <output> <path>\n\tMerges all profraw files from path into output.' % __file__
+    return 1
+  cmd = [args[0], 'merge', '-o', args[1]]
+  cmd.extend(findProfrawFiles(args[2]))
+  subprocess.check_call(cmd)
+  return 0
+
+commands = {'clean' : clean, 'merge' : merge}
+
+def main():
+  f = commands[sys.argv[1]]
+  sys.exit(f(sys.argv[2:]))
+
+if __name__ == '__main__':
+  main()