[OMPT] Add implementation and tests of Archer tool

[protze.joachim]

Summary

The tool provides TSAN annotations for OpenMP synchronization. Enabled for
application execution by setting OMP_TOOL_LIBRARIES=libarcher.so, this
library should get installed in the same order as libomp, so the linker
should find the file when the application is linked with OpenMP.

The tool detects whether the application was built with TSan and rejects
activation according to the OMPT protocol if there is no TSan-rt.

Further it is recommended to set
TSAN_OPTIONS="ignore_noninstrumented_modules=1"
This avoids some false positive errors from the OpenMP runtime.

[Hahnfeld]

Do we really want to call this tool Archer? I understand that it was written for that purpose but IMO this can serve a much more general purpose, even without the Archer "framework" around it.

[protze.joachim]

Reasons to keep the name archer (or archer-rt):

• We already have that name, we don't need to come up with a new name :)
• You can easily find related publications under that name, which explain the reasoning behind the library
• The programmer should never see the name, once the tool is integrated into the runtime workflow

[simoatze]

This looks great, thanks guys!
I agree, the name is mostly a "marketing" thing at this point, people know it in that way, changing it would be confusing.

[protze.joachim]

This will not compile with the current version of the OMPT interface, needs updates first

[protze.joachim]

The code is updated to be compatible with OMPT as in OpenMP 5.0.

The OpenMP runtime code is modified to automatically load Archer, which will itself only make active if the application is compiled with TSan.

We are currently in the process to relicense the code under "Apache License v2.0 with LLVM Exceptions", but this should have no influence to the code review.

[protze.joachim]

Relicensed Archer under Apache license, updated the files.

[Hahnfeld]

Some high-level comments inline

runtime/src/ompt-general.cpp

233–235 ↗

(On Diff #200309)

These preprocessor guards are redundant.

240–245 ↗

(On Diff #200309)

If it's not tested, it should be removed.

tools/CMakeLists.txt

7 ↗

(On Diff #200309)

Why do we need to handle this dummy?

tools/archer/CMakeLists.txt

1–4 ↗

(On Diff #200309)

I don't think this should be here...

tools/archer/LICENSE.txt

1–3 ↗

(On Diff #200309)

there is a LICENSE.txt in the openmp folder, I don't think we should have a copy in this subdirectory.

tools/archer/counter.h

2 ↗

(On Diff #200309)

counter.h

tools/archer/ftsan.c

2 ↗

(On Diff #200309)

Why do we need this in here? This should surely be handled in the compiler?

[protze.joachim]

Addressing Jonas' comments

tools/archer/ftsan.c

2 ↗

(On Diff #200309)

This allows to use those basic annotations of synchronization in Fortran code.
The annotation interface is also intended for manual instrumenting application code.

Like for SPEC OMP: 371.applu331/src/syncs.F90

@@ -82,6 +85,8 @@
 !$omp flush(isync)
          end do
+       CALL AnnotateHappensAfter(__FILE__, __LINE__, isync(omp_get_thread_num()))
+       CALL AnnotateHappensBefore(__FILE__, __LINE__, isync(iam))
          isync(iam) = 1
 !$omp flush(isync)
       endif

[protze.joachim]

Removed a file which was mistakenly added

[Hahnfeld]

More comments

tools/CMakeLists.txt

2 ↗

(On Diff #210043)

s/project/tool/

tools/archer/CMakeLists.txt

4 ↗

(On Diff #210043)

I think this should now say See https://llvm.org/LICENSE.txt for license information., at least that's what other files have.

17–18 ↗

(On Diff #210043)

Please use OPENMP_INSTALL_LIBDIR to handle libdir suffix.

tools/archer/ftsan.c

2 ↗

(On Diff #200309)

It's not required for Archer and belongs into the sanitizer runtime.

tools/archer/ompt-tsan.cpp

203 ↗

(On Diff #210043)

This should be standard now.

544 ↗

(On Diff #210043)

Indention looks odd...

720–721 ↗

(On Diff #210043)

?

747 ↗

(On Diff #210043)

?

tools/archer/tests/CMakeLists.txt

5 ↗

(On Diff #210043)

Do they?

33–34 ↗

(On Diff #210043)

At least these two don't exist here.

tools/archer/tests/lit.cfg

105–108 ↗

(On Diff #210043)

Is this needed?

117–130 ↗

(On Diff #210043)

Is this needed?

tools/archer/tests/lit.site.cfg.in

13–15 ↗

(On Diff #210043)

This should not be needed

tools/archer/tests/races/critical-unrelated.c

37 ↗

(On Diff #210043)

This depends on the compiler used, right? Can the tests be executed by GCC?

[protze.joachim]

tools/archer/ftsan.c

2 ↗

(On Diff #200309)

It doesn't harm to have this duplicately. I'm not sure how this would fit into the LLVM/sanitizer as long as there is no Fortran frontend supporting this sanitizer.

I moved the code to the other declarations in ompt-tsan.cpp.

[protze.joachim]

Addressed comments by Jonas.
The tests also support gcc now.

[Hahnfeld]

tools/archer/ompt-tsan.cpp

175–192 ↗

(On Diff #210350)

Moving the code doesn't solve the underlying issues:

1. It's not required for Archer, or at least for the basic tests to pass.
2. It's not related to OpenMP per se.

Besides, with the current usage to dynamically load the library during runtime, it will not resolve symbols during linkage.

383–384 ↗

(On Diff #210350)

This comment doesn't sound right.

923–924 ↗

(On Diff #210350)

This functionality is not used in the tests and could be a separate patch.

[Hahnfeld]

tools/archer/tests/lit.site.cfg.in

13–14 ↗

(On Diff #210350)

Still not needed

29–51 ↗

(On Diff #210350)

Not needed

[protze.joachim]

Removed the Fortran annotation functions :/
Fixed also the other comments

tools/archer/ompt-tsan.cpp

923–924 ↗

(On Diff #210350)

This functionality is useful for debugging errors resulting from errors in the OMPT implementation.

[Hahnfeld]

tools/archer/ompt-tsan.cpp

923–924 ↗

(On Diff #210350)

I agree, and this sounds like a good motivation for a second tool. What's the advantage of having this in ompt-tsan.cpp?

[protze.joachim]

Removed the counters as requested

[Hahnfeld]

The code itself looks good to me (it should probably be clang-formated). If others have comments, please raise them now.

Apart from that, I still found many unused lines in the testing framework...

tools/archer/README.md

168–177 ↗

(On Diff #219468)

Do we still want to speak of clang-archer?

tools/archer/tests/CMakeLists.txt

18–19 ↗

(On Diff #219468)

These variables are not defined, so I guess they can be safely removed

29–30 ↗

(On Diff #219468)

Likewise

tools/archer/tests/lit.cfg

53–62 ↗

(On Diff #219468)

I think these lines can be removed, see comments in CMakeLists.txt and implications

92–96 ↗

(On Diff #219468)

This can probably be removed

tools/archer/tests/lit.site.cfg.in

18–24 ↗

(On Diff #219468)

All of these are either not used or are probably not needed, see comment in CMakeLists.txt.

13–14 ↗

(On Diff #210350)

Ping, there's no definition of OPENMP_TEST_ARCHER_FLAGS and no use of test_archer_flags

tools/archer/tests/ompt/ompt-signal.h

2 ↗

(On Diff #219468)

We should probably work on deduplicating this from the OMPT tests. Not a strict requirement for now, the file is probably small enough...

[twoh]

openmp/tools/archer/tests/lit.site.cfg.in

13

@protze.joachim Shouldn't this be @LIBARCHER_HAVE_LIBATOMIC@ , based on openmp/tools/archer/tests/CMakeLists.txt? For our local unit test runs, they fail with

llvm-lit: /home/engshare/third-party2/llvm/src/llvm/utils/lit/lit/TestingConfig.py:102: fatal: unable to parse config file '/home/engshare/third-party2/llvm/src/build-centos7-native/build/projects/openmp/tools/archer/tests/lit.site.cfg', traceback: Traceback (most recent call last):
  File "/home/engshare/third-party2/llvm/src/llvm/utils/lit/lit/TestingConfig.py", line 89, in load_from_path
    exec(compile(data, path, 'exec'), cfg_globals, None)
  File "/home/engshare/third-party2/llvm/src/build-centos7-native/build/projects/openmp/tools/archer/tests/lit.site.cfg", line 14
    config.has_libatomic =
                          ^
SyntaxError: invalid syntax

[gribozavr2]

The newly added tests fail on buildbots: http://lab.llvm.org:8011/builders/openmp-gcc-x86_64-linux-debian/builds/236

Could you take a look? And please consider reverting in the meanwhile.

[protze.joachim]

In D45890#1756465, @gribozavr2 wrote:

The newly added tests fail on buildbots: http://lab.llvm.org:8011/builders/openmp-gcc-x86_64-linux-debian/builds/236

Could you take a look? And please consider reverting in the meanwhile.

Several things:

• the tests rely on the availability of thread-sanitizer
• I disabled the tests for standalone builds (as in the specific build-bot)
• in a follow-up review, I'll enable the tests based on llvm-config information

• MOST important: we should make the sanitizers available in the build-bot

[gribozavr2]

In D45890#1756747, @protze.joachim wrote:

• MOST important: we should make the sanitizers available in the build-bot

May I ask you to make the necessary changes to the bot configuration? It is here: https://github.com/llvm/llvm-zorg/blob/master/zorg/buildbot/builders/OpenMPBuilder.py

[gribozavr2]

In D45890#1756747, @protze.joachim wrote:

• the tests rely on the availability of thread-sanitizer

The tests should be annotated as REQUIRES: tsan or whatever the appropriate tag is.

[protze.joachim]

In D45890#1756796, @gribozavr2 wrote:

In D45890#1756747, @protze.joachim wrote:

• the tests rely on the availability of thread-sanitizer

The tests should be annotated as REQUIRES: tsan or whatever the appropriate tag is.

I pushed this change, so that the tests are off currently.
I'll create a review to check and announce this capability. (@Hahnfeld I think, you have experience in testing the test-compiler for features?)

Thanks for the pointer to the buildbot configuration, I'll have a look!

[gribozavr2]

Thank you very much for the quick workaround!

[aaronpuchert]

openmp/tools/archer/CMakeLists.txt

13–18

The commit message talks about setting OMP_TOOL_LIBRARIES=libarcher.so, so why do we build and install this as static library?

If there are uses for the static library, could we decide based on LIBOMP_ENABLE_SHARED or BUILD_SHARED_LIBS whether to build it?

openmp/CMakeLists.txt

if (APPLE OR WIN32)
     message(FATAL_ERROR "libomptarget cannot be built on Windows and MacOS X!")
   elseif (NOT OPENMP_HAVE_STD_CPP11_FLAG)
     message(FATAL_ERROR "Host compiler must support C++11 to build libomptarget!")
   endif()
 
   add_subdirectory(libomptarget)
 endif()
 
+set(ENABLE_OMPT_TOOLS ON)
+# Currently tools are not tested well on Windows or MacOS X.
+if (APPLE OR WIN32)
+  set(ENABLE_OMPT_TOOLS OFF)
+endif()
+
+option(OPENMP_ENABLE_OMPT_TOOLS "Enable building ompt based tools for OpenMP."
+       ${ENABLE_OMPT_TOOLS})
+if (OPENMP_ENABLE_OMPT_TOOLS)
+  add_subdirectory(tools)
+endif()
+
 # Now that we have seen all testuites, create the check-openmp target.
 construct_check_openmp_target()

openmp/runtime/CMakeLists.txt

if(${OPENMP_STANDALONE_BUILD})
   libomp_say("Use Adaptive locks   -- ${LIBOMP_USE_ADAPTIVE_LOCKS}")
   libomp_say("Use quad precision   -- ${LIBOMP_USE_QUAD_PRECISION}")
   libomp_say("Use TSAN-support     -- ${LIBOMP_TSAN_SUPPORT}")
   libomp_say("Use Hwloc library    -- ${LIBOMP_USE_HWLOC}")
 endif()
 
 add_subdirectory(src)
 add_subdirectory(test)
+
+# make these variables available for tools:
+set(LIBOMP_LIBRARY_DIR ${LIBOMP_LIBRARY_DIR} PARENT_SCOPE)
+set(LIBOMP_INCLUDE_DIR ${LIBOMP_INCLUDE_DIR} PARENT_SCOPE)

openmp/runtime/src/CMakeLists.txt

else()
   get_target_property(LIBOMP_LIBRARY_DIR omp RUNTIME_OUTPUT_DIRECTORY)
 endif()
 if(NOT LIBOMP_LIBRARY_DIR)
   set(LIBOMP_LIBRARY_DIR ${CMAKE_CURRENT_BINARY_DIR})
   set(LIBOMP_LIBRARY_DIR ${CMAKE_CURRENT_BINARY_DIR} PARENT_SCOPE)
 else()
   set(LIBOMP_LIBRARY_DIR ${LIBOMP_LIBRARY_DIR} PARENT_SCOPE)
 endif()
+set(LIBOMP_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR} PARENT_SCOPE)
 
 # Add symbolic links to libomp
 if(NOT WIN32)
   add_custom_command(TARGET omp POST_BUILD
     COMMAND ${CMAKE_COMMAND} -E create_symlink ${LIBOMP_LIB_FILE}
       libgomp${LIBOMP_LIBRARY_SUFFIX}
     COMMAND ${CMAKE_COMMAND} -E create_symlink ${LIBOMP_LIB_FILE}
       libiomp5${LIBOMP_LIBRARY_SUFFIX}

openmp/runtime/src/ompt-general.cpp

 #endif
         if (start_tool && (ret = (*start_tool)(omp_version, runtime_version)))
           break;
       }
       fname = __kmp_str_token(NULL, sep, &buf);
     }
     __kmp_str_free(&libs);
   }
+  if (ret)
+    return ret;
+
+#if KMP_OS_UNIX
+  { // Non-standard: load archer tool if application is built with TSan
+    const char *fname = "libarcher.so";
+    void *h = dlopen(fname, RTLD_LAZY);
+    if (h) {
+      start_tool = (ompt_start_tool_t)dlsym(h, "ompt_start_tool");
+      if (start_tool)
+        ret = (*start_tool)(omp_version, runtime_version);
+      if (ret)
+        return ret;
+    }
+  }
+#endif
   return ret;
 }
 
 void ompt_pre_init() {
   //--------------------------------------------------
   // Execute the pre-initialization logic only once.
   //--------------------------------------------------
   static int ompt_pre_initialized = 0;

openmp/tools/CMakeLists.txt

+# Discover the tools that use CMake in the subdirectories.
+# Note that explicit cmake invocation is required every time a new tool
+# is added or removed.
+file(GLOB entries *)
+foreach(entry ${entries})
+  if(IS_DIRECTORY ${entry} AND EXISTS ${entry}/CMakeLists.txt)
+    add_subdirectory(${entry})
+  endif()
+endforeach(entry)

openmp/tools/archer/CMakeLists.txt

+# //===----------------------------------------------------------------------===//
+# //
+# // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# // See https://llvm.org/LICENSE.txt for details.
+# // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+# //
+# //===----------------------------------------------------------------------===//
+  
+  
+
+include_directories(${LIBOMP_INCLUDE_DIR})
+
+add_library(archer SHARED ompt-tsan.cpp)
+add_library(archer_static STATIC ompt-tsan.cpp)
+
+install(TARGETS archer archer_static
+  LIBRARY DESTINATION ${OPENMP_INSTALL_LIBDIR}
+  ARCHIVE DESTINATION ${OPENMP_INSTALL_LIBDIR})
+
+add_subdirectory(tests)

openmp/tools/archer/README.md

+<div id="table-of-contents">
+<h2>Table of Contents</h2>
+<div id="text-table-of-contents">
+<ul>
+<li><a href="#org8ca70b5">1. License</a></li>
+<li><a href="#orgc6a2b10">2. Introduction</a></li>
+<li><a href="#org9a459f1">3. Installation</a></li>
+<li><a href="#orgb820ad0">4. Usage</a>
+<ul>
+<li><a href="#org213ff1a">4.1. How to compile</a></li>
+<li><a href="#org110062c">4.2. Runtime Flags</a></li>
+</ul>
+</li>
+<li><a href="#org73e58a9">5. Example</a></li>
+<li><a href="#orgcc38a36">6. Contacts and Support</a></li>
+</ul>
+</div>
+</div>
+
+
+<a id="org8ca70b5"></a>
+
+# License
+
+Archer is distributed under the terms of the Apache License.
+
+Please see LICENSE.txt for usage terms.
+
+LLNL-CODE-773957
+
+<a id="orgc6a2b10"></a>
+
+# Introduction
+
+**Archer** is an OMPT tool which annotates OpenMP synchronization semantics for data race
+detection.
+This avoids false alerts in data race detection.
+Archer is automatically loaded for OpenMP applications which are compiled
+with ThreadSanitizer option.
+
+<a id="org9a459f1"></a>
+
+# Build Archer within Clang/LLVM
+
+This distribution of Archer is automatically built with the OpenMP runtime
+and automatically loaded by the OpenMP runtime.
+
+<a id="orgb820ad0"></a>
+
+# Usage
+
+
+<a id="org213ff1a"></a>
+
+## How to compile
+
+To use archer, compile the application with the extra flag
+`-fsanitize=thread`:
+
+    clang -O3 -g -fopenmp -fsanitize=thread app.c
+    clang++ -O3 -g -fopenmp -fsanitize=thread app.cpp
+
+To compile Fortran applications, compile with gfortran, link with clang:
+
+    gfortran -g -c -fopenmp -fsanitize=thread app.f
+    clang -fopenmp -fsanitize=thread app.o -lgfortran
+
+
+<a id="org110062c"></a>
+
+## Runtime Flags
+
+TSan runtime flags are passed via **TSAN&#95;OPTIONS** environment variable,
+we highly recommend the following option to aviod false alerts for the
+OpenMP or MPI runtime implementation:
+
+    export TSAN_OPTIONS="ignore_noninstrumented_modules=1"
+
+
+Runtime flags are passed via **ARCHER&#95;OPTIONS** environment variable,
+different flags are separated by spaces, e.g.:
+
+    ARCHER_OPTIONS="flush_shadow=1" ./myprogram
+
+<table border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides">
+
+
+<colgroup>
+<col  class="org-left" />
+
+<col  class="org-right" />
+
+<col  class="org-left" />
+</colgroup>
+<thead>
+<tr>
+<th scope="col" class="org-left">Flag Name</th>
+<th scope="col" class="org-right">Default value</th>
+<th scope="col" class="org-left">Description</th>
+</tr>
+</thead>
+
+<tbody>
+<tr>
+<td class="org-left">flush&#95;shadow</td>
+<td class="org-right">0</td>
+<td class="org-left">Flush shadow memory at the end of an outer OpenMP parallel region. Our experiments show that this can reduce memory overhead by ~30% and runtime overhead by ~10%. This flag is useful for large OpenMP applications that typically require large amounts of memory, causing out-of-memory exceptions when checked by Archer.</td>
+</tr>
+</tbody>
+
+<tbody>
+<tr>
+<td class="org-left">print&#95;ompt&#95;counters</td>
+<td class="org-right">0</td>
+<td class="org-left">Print the number of triggered OMPT events at the end of the execution.</td>
+</tr>
+</tbody>
+
+<tbody>
+<tr>
+<td class="org-left">print&#95;max&#95;rss</td>
+<td class="org-right">0</td>
+<td class="org-left">Print the RSS memory peak at the end of the execution.</td>
+</tr>
+</tbody>
+
+<tbody>
+<tr>
+<td class="org-left">verbose</td>
+<td class="org-right">0</td>
+<td class="org-left">Print startup information.</td>
+</tr>
+</tbody>
+
+<tbody>
+<tr>
+<td class="org-left">enable</td>
+<td class="org-right">1</td>
+<td class="org-left">Use Archer runtime library during execution.</td>
+</tr>
+</tbody>
+</table>
+
+
+<a id="org73e58a9"></a>
+
+# Example
+
+Let us take the program below and follow the steps to compile and
+check the program for data races.
+
+Suppose our program is called *myprogram.c*:
+
+     1  #include <stdio.h>
+     2
+     3  #define N 1000
+     4
+     5  int main (int argc, char **argv)
+     6  {
+     7    int a[N];
+     8
+     9  #pragma omp parallel for
+    10    for (int i = 0; i < N - 1; i++) {
+    11      a[i] = a[i + 1];
+    12    }
+    13  }
+
+We compile the program as follow:
+
+    clang -fsanitize=thread -fopenmp -g myprogram.c -o myprogram
+
+Now we can run the program with the following commands:
+
+    export OMP_NUM_THREADS=2
+    ./myprogram
+
+Archer will output a report in case it finds data races. In our case
+the report will look as follow:
+
+    ==================
+    WARNING: ThreadSanitizer: data race (pid=13641)
+      Read of size 4 at 0x7fff79a01170 by main thread:
+        #0 .omp_outlined. myprogram.c:11:12 (myprogram+0x00000049b5a2)
+        #1 __kmp_invoke_microtask <null> (libomp.so+0x000000077842)
+        #2 __libc_start_main /build/glibc-t3gR2i/glibc-2.23/csu/../csu/libc-start.c:291 (libc.so.6+0x00000002082f)
+
+      Previous write of size 4 at 0x7fff79a01170 by thread T1:
+        #0 .omp_outlined. myprogram.c:11:10 (myprogram+0x00000049b5d6)
+        #1 __kmp_invoke_microtask <null> (libomp.so+0x000000077842)
+
+      Location is stack of main thread.
+
+      Thread T1 (tid=13643, running) created by main thread at:
+        #0 pthread_create tsan_interceptors.cc:902:3 (myprogram+0x00000043db75)
+        #1 __kmp_create_worker <null> (libomp.so+0x00000006c364)
+        #2 __libc_start_main /build/glibc-t3gR2i/glibc-2.23/csu/../csu/libc-start.c:291 (libc.so.6+0x00000002082f)
+
+    SUMMARY: ThreadSanitizer: data race myprogram.c:11:12 in .omp_outlined.
+    ==================
+    ThreadSanitizer: reported 1 warnings
+
+
+<a id="orgcc38a36"></a>
+
+# Contacts and Support
+
+-   [Google group](https://groups.google.com/forum/#!forum/archer-pruner)
+-   [Slack Channel](https://pruners.slack.com)
+
+    <ul style="list-style-type:circle"> <li> For an invitation please write an email to <a href="mailto:[e-mail]?Subject=[archer-slack] Slack Invitation" target="_top">Simone Atzeni</a> with a reason why you want to be part of the PRUNERS Slack Team. </li> </ul>
+-   E-Mail Contacts:
+
+    <ul style="list-style-type:circle"> <li> <a href="mailto:[e-mail]?Subject=[archer-dev]%20" target="_top">Simone Atzeni</a> </li> <li> <a href="mailto:[e-mail]?Subject=[archer-dev]%20" target="_top">Joachim Protze</a> </li> </ul>
+
+

openmp/tools/archer/ompt-tsan.cpp

+/*
+ * ompt-tsan.cpp -- Archer runtime library, TSan annotations for Archer
+ */
+  
+  //===----------------------------------------------------------------------===//
+  //
+  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+  // See https://llvm.org/LICENSE.txt for details.
+  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+  //
+  //===----------------------------------------------------------------------===//
+
+
+#ifndef __STDC_FORMAT_MACROS
+#define __STDC_FORMAT_MACROS
+#endif
+
+#include <atomic>
+#include <cassert>
+#include <cstdlib>
+#include <cstring>
+#include <inttypes.h>
+#include <iostream>
+#include <mutex>
+#include <sstream>
+#include <stack>
+#include <list>
+#include <string>
+#include <iostream>
+#include <unordered_map>
+#include <vector>
+
+#if (defined __APPLE__ && defined __MACH__)
+#include <dlfcn.h>
+#endif
+
+#include <sys/resource.h>
+#include "omp-tools.h"
+
+static int runOnTsan;
+static int hasReductionCallback;
+
+class ArcherFlags {
+public:
+#if (LLVM_VERSION) >= 40
+  int flush_shadow;
+#endif
+  int print_max_rss;
+  int verbose;
+  int enabled;
+
+  ArcherFlags(const char *env)
+      :
+#if (LLVM_VERSION) >= 40
+        flush_shadow(0),
+#endif
+        print_max_rss(0), verbose(0), enabled(1) {
+    if (env) {
+      std::vector<std::string> tokens;
+      std::string token;
+      std::string str(env);
+      std::istringstream iss(str);
+      while (std::getline(iss, token, ' '))
+        tokens.push_back(token);
+
+      for (std::vector<std::string>::iterator it = tokens.begin();
+           it != tokens.end(); ++it) {
+#if (LLVM_VERSION) >= 40
+        if (sscanf(it->c_str(), "flush_shadow=%d", &flush_shadow))
+          continue;
+#endif
+        if (sscanf(it->c_str(), "print_max_rss=%d", &print_max_rss))
+          continue;
+        if (sscanf(it->c_str(), "verbose=%d", &verbose))
+          continue;
+        if (sscanf(it->c_str(), "enable=%d", &enabled))
+          continue;
+        std::cerr << "Illegal values for ARCHER_OPTIONS variable: " << token
+                  << std::endl;
+      }
+    }
+  }
+};
+
+#if (LLVM_VERSION) >= 40
+extern "C" {
+int __attribute__((weak)) __archer_get_omp_status();
+void __attribute__((weak)) __tsan_flush_memory() {}
+}
+#endif
+ArcherFlags *archer_flags;
+
+// The following definitions are pasted from "llvm/Support/Compiler.h" to allow
+// the code
+// to be compiled with other compilers like gcc:
+
+#ifndef TsanHappensBefore
+// Thread Sanitizer is a tool that finds races in code.
+// See http://code.google.com/p/data-race-test/wiki/DynamicAnnotations .
+// tsan detects these exact functions by name.
+extern "C" {
+#if (defined __APPLE__ && defined __MACH__)
+static void AnnotateHappensAfter(const char *file, int line,
+                                 const volatile void *cv) {
+  void (*fptr)(const char *, int, const volatile void *);
+
+  fptr = (void (*)(const char *, int, const volatile void *))dlsym(
+      RTLD_DEFAULT, "AnnotateHappensAfter");
+  (*fptr)(file, line, cv);
+}
+static void AnnotateHappensBefore(const char *file, int line,
+                                  const volatile void *cv) {
+  void (*fptr)(const char *, int, const volatile void *);
+
+  fptr = (void (*)(const char *, int, const volatile void *))dlsym(
+      RTLD_DEFAULT, "AnnotateHappensBefore");
+  (*fptr)(file, line, cv);
+}
+static void AnnotateIgnoreWritesBegin(const char *file, int line) {
+  void (*fptr)(const char *, int);
+
+  fptr = (void (*)(const char *, int))dlsym(RTLD_DEFAULT,
+                                            "AnnotateIgnoreWritesBegin");
+  (*fptr)(file, line);
+}
+static void AnnotateIgnoreWritesEnd(const char *file, int line) {
+  void (*fptr)(const char *, int);
+
+  fptr = (void (*)(const char *, int))dlsym(RTLD_DEFAULT,
+                                            "AnnotateIgnoreWritesEnd");
+  (*fptr)(file, line);
+}
+static void AnnotateNewMemory(const char *file, int line,
+                              const volatile void *cv, size_t size) {
+  void (*fptr)(const char *, int, const volatile void *, size_t);
+
+  fptr = (void (*)(const char *, int, const volatile void *, size_t))dlsym(
+      RTLD_DEFAULT, "AnnotateNewMemory");
+  (*fptr)(file, line, cv, size);
+}
+static int RunningOnValgrind() {
+  int (*fptr)();
+
+  fptr = (int (*)())dlsym(RTLD_DEFAULT, "RunningOnValgrind");
+  if (fptr && fptr != RunningOnValgrind)
+    runOnTsan = 0;
+  return 0;
+}
+#else
+void __attribute__((weak))
+AnnotateHappensAfter(const char *file, int line, const volatile void *cv) {}
+void __attribute__((weak))
+AnnotateHappensBefore(const char *file, int line, const volatile void *cv) {}
+void __attribute__((weak))
+AnnotateIgnoreWritesBegin(const char *file, int line) {}
+void __attribute__((weak)) AnnotateIgnoreWritesEnd(const char *file, int line) {
+}
+void __attribute__((weak))
+AnnotateNewMemory(const char *file, int line, const volatile void *cv,
+                  size_t size) {}
+int __attribute__((weak)) RunningOnValgrind() {
+  runOnTsan = 0;
+  return 0;
+}
+#endif
+}
+
+// This marker is used to define a happens-before arc. The race detector will
+// infer an arc from the begin to the end when they share the same pointer
+// argument.
+#define TsanHappensBefore(cv) AnnotateHappensBefore(__FILE__, __LINE__, cv)
+
+// This marker defines the destination of a happens-before arc.
+#define TsanHappensAfter(cv) AnnotateHappensAfter(__FILE__, __LINE__, cv)
+
+// Ignore any races on writes between here and the next TsanIgnoreWritesEnd.
+#define TsanIgnoreWritesBegin() AnnotateIgnoreWritesBegin(__FILE__, __LINE__)
+
+// Resume checking for racy writes.
+#define TsanIgnoreWritesEnd() AnnotateIgnoreWritesEnd(__FILE__, __LINE__)
+
+// We don't really delete the clock for now
+#define TsanDeleteClock(cv)
+
+// newMemory
+#define TsanNewMemory(addr, size)                                              \
+  AnnotateNewMemory(__FILE__, __LINE__, addr, size)
+#define TsanFreeMemory(addr, size)                                             \
+  AnnotateNewMemory(__FILE__, __LINE__, addr, size)
+#endif
+
+/// Required OMPT inquiry functions.
+static ompt_get_parallel_info_t ompt_get_parallel_info;
+static ompt_get_thread_data_t ompt_get_thread_data;
+
+typedef uint64_t ompt_tsan_clockid;
+
+static uint64_t my_next_id() {
+  static uint64_t ID = 0;
+  uint64_t ret = __sync_fetch_and_add(&ID, 1);
+  return ret;
+}
+
+// Data structure to provide a threadsafe pool of reusable objects.
+// DataPool<Type of objects, Size of blockalloc>
+template <typename T, int N> struct DataPool {
+  std::mutex DPMutex;
+  std::stack<T *> DataPointer;
+  std::list<void *> memory;
+  int total;
+
+  void newDatas() {
+    // prefix the Data with a pointer to 'this', allows to return memory to
+    // 'this',
+    // without explicitly knowing the source.
+    //
+    // To reduce lock contention, we use thread local DataPools, but Data
+    // objects move to other threads.
+    // The strategy is to get objects from local pool. Only if the object moved
+    // to another
+    // thread, we might see a penalty on release (returnData).
+    // For "single producer" pattern, a single thread creates tasks, these are
+    // executed by other threads.
+    // The master will have a high demand on TaskData, so return after use.
+    struct pooldata {
+      DataPool<T, N> *dp;
+      T data;
+    };
+    // We alloc without initialize the memory. We cannot call constructors.
+    // Therfore use malloc!
+    pooldata *datas = (pooldata *)malloc(sizeof(pooldata) * N);
+    memory.push_back(datas);
+    for (int i = 0; i < N; i++) {
+      datas[i].dp = this;
+      DataPointer.push(&(datas[i].data));
+    }
+    total += N;
+  }
+
+  T *getData() {
+    T *ret;
+    DPMutex.lock();
+    if (DataPointer.empty())
+      newDatas();
+    ret = DataPointer.top();
+    DataPointer.pop();
+    DPMutex.unlock();
+    return ret;
+  }
+
+  void returnData(T *data) {
+    DPMutex.lock();
+    DataPointer.push(data);
+    DPMutex.unlock();
+  }
+
+  void getDatas(int n, T **datas) {
+    DPMutex.lock();
+    for (int i = 0; i < n; i++) {
+      if (DataPointer.empty())
+        newDatas();
+      datas[i] = DataPointer.top();
+      DataPointer.pop();
+    }
+    DPMutex.unlock();
+  }
+
+  void returnDatas(int n, T **datas) {
+    DPMutex.lock();
+    for (int i = 0; i < n; i++) {
+      DataPointer.push(datas[i]);
+    }
+    DPMutex.unlock();
+  }
+
+  DataPool() : DPMutex(), DataPointer(), total(0) {}
+
+  ~DataPool() {
+    // we assume all memory is returned when the thread finished / destructor is
+    // called
+    for (auto i : memory)
+      if (i)
+        free(i);
+  }
+};
+
+// This function takes care to return the data to the originating DataPool
+// A pointer to the originating DataPool is stored just before the actual data.
+template <typename T, int N> static void retData(void *data) {
+  ((DataPool<T, N> **)data)[-1]->returnData((T *)data);
+}
+
+struct ParallelData;
+__thread DataPool<ParallelData, 4> *pdp;
+
+/// Data structure to store additional information for parallel regions.
+struct ParallelData {
+
+  // Parallel fork is just another barrier, use Barrier[1]
+
+  /// Two addresses for relationships with barriers.
+  ompt_tsan_clockid Barrier[2];
+
+  void *GetParallelPtr() { return &(Barrier[1]); }
+
+  void *GetBarrierPtr(unsigned Index) { return &(Barrier[Index]); }
+
+  ~ParallelData() {
+    TsanDeleteClock(&(Barrier[0]));
+    TsanDeleteClock(&(Barrier[1]));
+  }
+  // overload new/delete to use DataPool for memory management.
+  void *operator new(size_t size) { return pdp->getData(); }
+  void operator delete(void *p, size_t) { retData<ParallelData, 4>(p); }
+};
+
+static inline ParallelData *ToParallelData(ompt_data_t *parallel_data) {
+  return reinterpret_cast<ParallelData *>(parallel_data->ptr);
+}
+
+struct Taskgroup;
+__thread DataPool<Taskgroup, 4> *tgp;
+
+/// Data structure to support stacking of taskgroups and allow synchronization.
+struct Taskgroup {
+  /// Its address is used for relationships of the taskgroup's task set.
+  ompt_tsan_clockid Ptr;
+
+  /// Reference to the parent taskgroup.
+  Taskgroup *Parent;
+
+  Taskgroup(Taskgroup *Parent) : Parent(Parent) {}
+  ~Taskgroup() { TsanDeleteClock(&Ptr); }
+
+  void *GetPtr() { return &Ptr; }
+  // overload new/delete to use DataPool for memory management.
+  void *operator new(size_t size) { return tgp->getData(); }
+  void operator delete(void *p, size_t) { retData<Taskgroup, 4>(p); }
+};
+
+struct TaskData;
+__thread DataPool<TaskData, 4> *tdp;
+
+/// Data structure to store additional information for tasks.
+struct TaskData {
+  /// Its address is used for relationships of this task.
+  ompt_tsan_clockid Task;
+
+  /// Child tasks use its address to declare a relationship to a taskwait in
+  /// this task.
+  ompt_tsan_clockid Taskwait;
+
+  /// Whether this task is currently executing a barrier.
+  bool InBarrier;
+
+  /// Whether this task is an included task.
+  bool Included;
+
+  /// Index of which barrier to use next.
+  char BarrierIndex;
+
+  /// Count how often this structure has been put into child tasks + 1.
+  std::atomic_int RefCount;
+
+  /// Reference to the parent that created this task.
+  TaskData *Parent;
+
+  /// Reference to the implicit task in the stack above this task.
+  TaskData *ImplicitTask;
+
+  /// Reference to the team of this task.
+  ParallelData *Team;
+
+  /// Reference to the current taskgroup that this task either belongs to or
+  /// that it just created.
+  Taskgroup *TaskGroup;
+
+  /// Dependency information for this task.
+  ompt_dependence_t *Dependencies;
+
+  /// Number of dependency entries.
+  unsigned DependencyCount;
+
+  void *PrivateData;
+  size_t PrivateDataSize;
+
+  int execution;
+  int freed;
+
+  TaskData(TaskData *Parent)
+      : InBarrier(false), Included(false), BarrierIndex(0), RefCount(1),
+        Parent(Parent), ImplicitTask(nullptr), Team(Parent->Team),
+        TaskGroup(nullptr), DependencyCount(0), execution(0), freed(0) {
+    if (Parent != nullptr) {
+      Parent->RefCount++;
+      // Copy over pointer to taskgroup. This task may set up its own stack
+      // but for now belongs to its parent's taskgroup.
+      TaskGroup = Parent->TaskGroup;
+    }
+  }
+
+  TaskData(ParallelData *Team = nullptr)
+      : InBarrier(false), Included(false), BarrierIndex(0), RefCount(1),
+        Parent(nullptr), ImplicitTask(this), Team(Team), TaskGroup(nullptr),
+        DependencyCount(0), execution(1), freed(0) {}
+
+  ~TaskData() {
+    TsanDeleteClock(&Task);
+    TsanDeleteClock(&Taskwait);
+  }
+
+  void *GetTaskPtr() { return &Task; }
+
+  void *GetTaskwaitPtr() { return &Taskwait; }
+  // overload new/delete to use DataPool for memory management.
+  void *operator new(size_t size) { return tdp->getData(); }
+  void operator delete(void *p, size_t) { retData<TaskData, 4>(p); }
+};
+
+static inline TaskData *ToTaskData(ompt_data_t *task_data) {
+  return reinterpret_cast<TaskData *>(task_data->ptr);
+}
+
+static inline void *ToInAddr(void *OutAddr) {
+  // FIXME: This will give false negatives when a second variable lays directly
+  //        behind a variable that only has a width of 1 byte.
+  //        Another approach would be to "negate" the address or to flip the
+  //        first bit...
+  return reinterpret_cast<char *>(OutAddr) + 1;
+}
+
+/// Store a mutex for each wait_id to resolve race condition with callbacks.
+std::unordered_map<ompt_wait_id_t, std::mutex> Locks;
+std::mutex LocksMutex;
+
+static void ompt_tsan_thread_begin(ompt_thread_t thread_type,
+                                   ompt_data_t *thread_data) {
+  pdp = new DataPool<ParallelData, 4>;
+  TsanNewMemory(pdp, sizeof(pdp));
+  tgp = new DataPool<Taskgroup, 4>;
+  TsanNewMemory(tgp, sizeof(tgp));
+  tdp = new DataPool<TaskData, 4>;
+  TsanNewMemory(tdp, sizeof(tdp));
+  thread_data->value = my_next_id();
+}
+
+static void ompt_tsan_thread_end(ompt_data_t *thread_data) {
+  delete pdp;
+  delete tgp;
+  delete tdp;
+}
+
+/// OMPT event callbacks for handling parallel regions.
+
+static void ompt_tsan_parallel_begin(ompt_data_t *parent_task_data,
+                                     const ompt_frame_t *parent_task_frame,
+                                     ompt_data_t *parallel_data,
+                                     uint32_t requested_team_size,
+                                     int flag,
+                                     const void *codeptr_ra) {
+  ParallelData *Data = new ParallelData;
+  parallel_data->ptr = Data;
+
+  TsanHappensBefore(Data->GetParallelPtr());
+}
+
+static void ompt_tsan_parallel_end(ompt_data_t *parallel_data,
+                                   ompt_data_t *task_data,
+                                   int flag,
+                                   const void *codeptr_ra) {
+  ParallelData *Data = ToParallelData(parallel_data);
+  TsanHappensAfter(Data->GetBarrierPtr(0));
+  TsanHappensAfter(Data->GetBarrierPtr(1));
+
+  delete Data;
+
+#if (LLVM_VERSION >= 40)
+  if (&__archer_get_omp_status) {
+    if (__archer_get_omp_status() == 0 && archer_flags->flush_shadow)
+      __tsan_flush_memory();
+  }
+#endif
+
+}
+
+static void ompt_tsan_implicit_task(ompt_scope_endpoint_t endpoint,
+                                    ompt_data_t *parallel_data,
+                                    ompt_data_t *task_data,
+                                    unsigned int team_size,
+                                    unsigned int thread_num,
+                                    int type) {
+  switch (endpoint) {
+  case ompt_scope_begin:
+    task_data->ptr = new TaskData(ToParallelData(parallel_data));
+    TsanHappensAfter(ToParallelData(parallel_data)->GetParallelPtr());
+    break;
+  case ompt_scope_end:
+    TaskData *Data = ToTaskData(task_data);
+    assert(Data->freed == 0 && "Implicit task end should only be called once!");
+    Data->freed = 1;
+    assert(Data->RefCount == 1 &&
+           "All tasks should have finished at the implicit barrier!");
+    delete Data;
+    break;
+  }
+}
+
+static void ompt_tsan_sync_region(ompt_sync_region_t kind,
+                                  ompt_scope_endpoint_t endpoint,
+                                  ompt_data_t *parallel_data,
+                                  ompt_data_t *task_data,
+                                  const void *codeptr_ra) {
+  TaskData *Data = ToTaskData(task_data);
+  switch (endpoint) {
+  case ompt_scope_begin:
+    switch (kind) {
+      case ompt_sync_region_barrier_implementation:
+      case ompt_sync_region_barrier_implicit:
+      case ompt_sync_region_barrier_explicit:
+      case ompt_sync_region_barrier: {
+        char BarrierIndex = Data->BarrierIndex;
+        TsanHappensBefore(Data->Team->GetBarrierPtr(BarrierIndex));
+
+        if (hasReductionCallback < ompt_set_always) {
+          // We ignore writes inside the barrier. These would either occur during
+          // 1. reductions performed by the runtime which are guaranteed to be
+          // race-free.
+          // 2. execution of another task.
+          // For the latter case we will re-enable tracking in task_switch.
+          Data->InBarrier = true;
+          TsanIgnoreWritesBegin();
+        }
+
+        break;
+      }
+
+      case ompt_sync_region_taskwait:
+        break;
+
+      case ompt_sync_region_taskgroup:
+        Data->TaskGroup = new Taskgroup(Data->TaskGroup);
+        break;
+
+      default:
+        break;
+    }
+    break;
+  case ompt_scope_end:
+    switch (kind) {
+      case ompt_sync_region_barrier_implementation:
+      case ompt_sync_region_barrier_implicit:
+      case ompt_sync_region_barrier_explicit:
+      case ompt_sync_region_barrier: {
+        if (hasReductionCallback < ompt_set_always) {
+          // We want to track writes after the barrier again.
+          Data->InBarrier = false;
+          TsanIgnoreWritesEnd();
+        }
+
+        char BarrierIndex = Data->BarrierIndex;
+        // Barrier will end after it has been entered by all threads.
+        if (parallel_data)
+          TsanHappensAfter(Data->Team->GetBarrierPtr(BarrierIndex));
+
+        // It is not guaranteed that all threads have exited this barrier before
+        // we enter the next one. So we will use a different address.
+        // We are however guaranteed that this current barrier is finished
+        // by the time we exit the next one. So we can then reuse the first
+        // address.
+        Data->BarrierIndex = (BarrierIndex + 1) % 2;
+        break;
+      }
+
+      case ompt_sync_region_taskwait: {
+        if (Data->execution > 1)
+          TsanHappensAfter(Data->GetTaskwaitPtr());
+        break;
+      }
+
+      case ompt_sync_region_taskgroup: {
+        assert(Data->TaskGroup != nullptr &&
+               "Should have at least one taskgroup!");
+
+        TsanHappensAfter(Data->TaskGroup->GetPtr());
+
+        // Delete this allocated taskgroup, all descendent task are finished by
+        // now.
+        Taskgroup *Parent = Data->TaskGroup->Parent;
+        delete Data->TaskGroup;
+        Data->TaskGroup = Parent;
+        break;
+      }
+
+      default:
+        break;
+    }
+    break;
+  }
+}
+
+static void ompt_tsan_reduction(ompt_sync_region_t kind,
+                                ompt_scope_endpoint_t endpoint,
+                                ompt_data_t *parallel_data,
+                                ompt_data_t *task_data,
+                                const void *codeptr_ra) {
+  switch (endpoint) {
+  case ompt_scope_begin:
+    switch (kind) {
+      case ompt_sync_region_reduction:
+        TsanIgnoreWritesBegin();
+        break;
+      default:
+        break;
+    }
+    break;
+  case ompt_scope_end:
+    switch (kind) {
+      case ompt_sync_region_reduction:
+        TsanIgnoreWritesEnd();
+        break;
+      default:
+        break;
+    }
+    break;
+  }
+}
+
+/// OMPT event callbacks for handling tasks.
+
+static void ompt_tsan_task_create(
+    ompt_data_t *parent_task_data, /* id of parent task            */
+    const ompt_frame_t *parent_frame, /* frame data for parent task   */
+    ompt_data_t *new_task_data, /* id of created task           */
+    int type, int has_dependences,
+    const void *codeptr_ra) /* pointer to outlined function */
+{
+  TaskData *Data;
+  assert(new_task_data->ptr == NULL &&
+         "Task data should be initialized to NULL");
+  if (type & ompt_task_initial) {
+    ompt_data_t *parallel_data;
+    int team_size = 1;
+    ompt_get_parallel_info(0, &parallel_data, &team_size);
+    ParallelData *PData = new ParallelData;
+    parallel_data->ptr = PData;
+
+    Data = new TaskData(PData);
+    new_task_data->ptr = Data;
+  } else if (type & ompt_task_undeferred) {
+    Data = new TaskData(ToTaskData(parent_task_data));
+    new_task_data->ptr = Data;
+    Data->Included = true;
+  } else if (type & ompt_task_explicit || type & ompt_task_target) {
+    Data = new TaskData(ToTaskData(parent_task_data));
+    new_task_data->ptr = Data;
+
+    // Use the newly created address. We cannot use a single address from the
+    // parent because that would declare wrong relationships with other
+    // sibling tasks that may be created before this task is started!
+    TsanHappensBefore(Data->GetTaskPtr());
+    ToTaskData(parent_task_data)->execution++;
+  }
+}
+
+static void ompt_tsan_task_schedule(ompt_data_t *first_task_data,
+                                    ompt_task_status_t prior_task_status,
+                                    ompt_data_t *second_task_data) {
+  TaskData *FromTask = ToTaskData(first_task_data);
+  TaskData *ToTask = ToTaskData(second_task_data);
+
+  if (ToTask->Included && prior_task_status != ompt_task_complete)
+    return; // No further synchronization for begin included tasks
+  if (FromTask->Included && prior_task_status == ompt_task_complete) {
+    // Just delete the task:
+    while (FromTask != nullptr && --FromTask->RefCount == 0) {
+      TaskData *Parent = FromTask->Parent;
+      if (FromTask->DependencyCount > 0) {
+        delete[] FromTask->Dependencies;
+      }
+      delete FromTask;
+      FromTask = Parent;
+    }
+    return;
+  }
+
+  if (ToTask->execution == 0) {
+    ToTask->execution++;
+    // 1. Task will begin execution after it has been created.
+    TsanHappensAfter(ToTask->GetTaskPtr());
+    for (unsigned i = 0; i < ToTask->DependencyCount; i++) {
+      ompt_dependence_t *Dependency = &ToTask->Dependencies[i];
+
+      TsanHappensAfter(Dependency->variable.ptr);
+      // in and inout dependencies are also blocked by prior in dependencies!
+      if (Dependency->dependence_type == ompt_dependence_type_out || Dependency->dependence_type == ompt_dependence_type_inout) {
+        TsanHappensAfter(ToInAddr(Dependency->variable.ptr));
+      }
+    }
+  } else {
+    // 2. Task will resume after it has been switched away.
+    TsanHappensAfter(ToTask->GetTaskPtr());
+  }
+
+  if (prior_task_status != ompt_task_complete) {
+    ToTask->ImplicitTask = FromTask->ImplicitTask;
+    assert(ToTask->ImplicitTask != NULL &&
+           "A task belongs to a team and has an implicit task on the stack");
+  }
+
+  // Task may be resumed at a later point in time.
+  TsanHappensBefore(FromTask->GetTaskPtr());
+
+  if (hasReductionCallback < ompt_set_always && FromTask->InBarrier) {
+    // We want to ignore writes in the runtime code during barriers,
+    // but not when executing tasks with user code!
+    TsanIgnoreWritesEnd();
+  }
+
+  if (prior_task_status == ompt_task_complete) { // task finished
+
+    // Task will finish before a barrier in the surrounding parallel region ...
+    ParallelData *PData = FromTask->Team;
+    TsanHappensBefore(
+        PData->GetBarrierPtr(FromTask->ImplicitTask->BarrierIndex));
+
+    // ... and before an eventual taskwait by the parent thread.
+    TsanHappensBefore(FromTask->Parent->GetTaskwaitPtr());
+
+    if (FromTask->TaskGroup != nullptr) {
+      // This task is part of a taskgroup, so it will finish before the
+      // corresponding taskgroup_end.
+      TsanHappensBefore(FromTask->TaskGroup->GetPtr());
+    }
+    for (unsigned i = 0; i < FromTask->DependencyCount; i++) {
+      ompt_dependence_t *Dependency = &FromTask->Dependencies[i];
+
+      // in dependencies block following inout and out dependencies!
+      TsanHappensBefore(ToInAddr(Dependency->variable.ptr));
+      if (Dependency->dependence_type == ompt_dependence_type_out || Dependency->dependence_type == ompt_dependence_type_inout) {
+        TsanHappensBefore(Dependency->variable.ptr);
+      }
+    }
+    while (FromTask != nullptr && --FromTask->RefCount == 0) {
+      TaskData *Parent = FromTask->Parent;
+      if (FromTask->DependencyCount > 0) {
+        delete[] FromTask->Dependencies;
+      }
+      delete FromTask;
+      FromTask = Parent;
+    }
+  }
+  if (hasReductionCallback < ompt_set_always && ToTask->InBarrier) {
+    // We re-enter runtime code which currently performs a barrier.
+    TsanIgnoreWritesBegin();
+  }
+}
+
+static void ompt_tsan_dependences(ompt_data_t *task_data,
+                                  const ompt_dependence_t *deps,
+                                  int ndeps) {
+  if (ndeps > 0) {
+    // Copy the data to use it in task_switch and task_end.
+    TaskData *Data = ToTaskData(task_data);
+    Data->Dependencies = new ompt_dependence_t[ndeps];
+    std::memcpy(Data->Dependencies, deps,
+                sizeof(ompt_dependence_t) * ndeps);
+    Data->DependencyCount = ndeps;
+
+    // This callback is executed before this task is first started.
+    TsanHappensBefore(Data->GetTaskPtr());
+  }
+}
+
+/// OMPT event callbacks for handling locking.
+static void ompt_tsan_mutex_acquired(ompt_mutex_t kind,
+                                     ompt_wait_id_t wait_id,
+                                     const void *codeptr_ra) {
+
+  // Acquire our own lock to make sure that
+  // 1. the previous release has finished.
+  // 2. the next acquire doesn't start before we have finished our release.
+    LocksMutex.lock();
+    std::mutex &Lock = Locks[wait_id];
+    LocksMutex.unlock();
+
+    Lock.lock();
+    TsanHappensAfter(&Lock);
+}
+
+static void ompt_tsan_mutex_released(ompt_mutex_t kind,
+                                     ompt_wait_id_t wait_id,
+                                     const void *codeptr_ra) {
+    LocksMutex.lock();
+    std::mutex &Lock = Locks[wait_id];
+    LocksMutex.unlock();
+    TsanHappensBefore(&Lock);
+
+    Lock.unlock();
+}
+
+// callback , signature , variable to store result , required support level
+#define SET_OPTIONAL_CALLBACK_T(event, type, result, level)                             \
+  do {                                                                                  \
+    ompt_callback_##type##_t tsan_##event = &ompt_tsan_##event;                         \
+    result = ompt_set_callback(ompt_callback_##event,                                   \
+                                (ompt_callback_t)tsan_##event);                         \
+    if (result < level)                                                                 \
+      printf("Registered callback '" #event "' is not supported at " #level " (%i)\n",  \
+             result);                                                                   \
+  } while (0)
+
+#define SET_CALLBACK_T(event, type)                              \
+  do {                                                           \
+    int res;                                                     \
+    SET_OPTIONAL_CALLBACK_T(event, type, res, ompt_set_always);  \
+  } while (0)
+
+#define SET_CALLBACK(event) SET_CALLBACK_T(event, event)
+
+static int ompt_tsan_initialize(ompt_function_lookup_t lookup,
+                                int device_num,
+                                ompt_data_t *tool_data) {
+  const char *options = getenv("ARCHER_OPTIONS");
+  archer_flags = new ArcherFlags(options);
+
+  ompt_set_callback_t ompt_set_callback =
+      (ompt_set_callback_t)lookup("ompt_set_callback");
+  if (ompt_set_callback == NULL) {
+    std::cerr << "Could not set callback, exiting..." << std::endl;
+    std::exit(1);
+  }
+  ompt_get_parallel_info =
+      (ompt_get_parallel_info_t)lookup("ompt_get_parallel_info");
+  ompt_get_thread_data = (ompt_get_thread_data_t)lookup("ompt_get_thread_data");
+
+  if (ompt_get_parallel_info == NULL) {
+    fprintf(stderr, "Could not get inquiry function 'ompt_get_parallel_info', "
+                    "exiting...\n");
+    exit(1);
+  }
+
+  SET_CALLBACK(thread_begin);
+  SET_CALLBACK(thread_end);
+  SET_CALLBACK(parallel_begin);
+  SET_CALLBACK(implicit_task);
+  SET_CALLBACK(sync_region);
+  SET_CALLBACK(parallel_end);
+
+  SET_CALLBACK(task_create);
+  SET_CALLBACK(task_schedule);
+  SET_CALLBACK(dependences);
+
+  SET_CALLBACK_T(mutex_acquired, mutex);
+  SET_CALLBACK_T(mutex_released, mutex);
+  SET_OPTIONAL_CALLBACK_T(reduction, sync_region, hasReductionCallback, ompt_set_never);
+  return 1; // success
+}
+
+static void ompt_tsan_finalize(ompt_data_t *tool_data) {
+  if (archer_flags->print_max_rss) {
+    struct rusage end;
+    getrusage(RUSAGE_SELF, &end);
+    printf("MAX RSS[KBytes] during execution: %ld\n", end.ru_maxrss);
+  }
+
+  if (archer_flags)
+    delete archer_flags;
+}
+
+extern "C"
+ompt_start_tool_result_t *ompt_start_tool(unsigned int omp_version,
+                                          const char *runtime_version) {
+  const char *options = getenv("ARCHER_OPTIONS");
+  archer_flags = new ArcherFlags(options);
+  if (!archer_flags->enabled)
+  {
+    if (archer_flags->verbose)
+      std::cout << "Archer disabled, stopping operation"
+                << std::endl;
+    delete archer_flags;
+    return NULL;
+  }
+  
+  static ompt_start_tool_result_t ompt_start_tool_result = {
+      &ompt_tsan_initialize, &ompt_tsan_finalize, {0}};
+  runOnTsan=1;
+  RunningOnValgrind();
+  if (!runOnTsan) // if we are not running on TSAN, give a different tool the
+    // chance to be loaded
+  {
+    if (archer_flags->verbose)
+      std::cout << "Archer detected OpenMP application without TSan "
+                   "stopping operation"
+                << std::endl;
+    delete archer_flags;
+    return NULL;
+  }
+
+  if (archer_flags->verbose)
+    std::cout << "Archer detected OpenMP application with TSan, supplying "
+                 "OpenMP synchronization semantics"
+              << std::endl;
+  return &ompt_start_tool_result;
+}

openmp/tools/archer/tests/CMakeLists.txt

+# CMakeLists.txt file for unit testing Archer runtime library.
+include(CheckFunctionExists)
+include(CheckLibraryExists)
+
+# When using libgcc, -latomic may be needed for atomics
+# (but when using compiler-rt, the atomics will be built-in)
+# Note: we can not check for __atomic_load because clang treats it
+# as special built-in and that breaks CMake checks
+check_function_exists(__atomic_load_1 LIBARCHER_HAVE_BUILTIN_ATOMIC)
+if(NOT LIBARCHER_HAVE_BUILTIN_ATOMIC)
+  check_library_exists(atomic __atomic_load_1 "" LIBARCHER_HAVE_LIBATOMIC)
+else()
+  # not needed
+  set(LIBARCHER_HAVE_LIBATOMIC 0)
+endif()
+
+set(LIBARCHER_TEST_PATH ${CMAKE_CURRENT_SOURCE_DIR})
+
+macro(pythonize_bool var)
+  if (${var})
+    set(${var} True)
+  else()
+    set(${var} False)
+  endif()
+endmacro()
+
+pythonize_bool(LIBARCHER_HAVE_LIBATOMIC)
+
+add_openmp_testsuite(check-libarcher "Running libarcher tests" ${CMAKE_CURRENT_BINARY_DIR} DEPENDS archer)
+
+# Configure the lit.site.cfg.in file
+set(AUTO_GEN_COMMENT "## Autogenerated by libarcher configuration.\n# Do not edit!")
+configure_file(lit.site.cfg.in lit.site.cfg @ONLY)

openmp/tools/archer/tests/barrier/barrier.c

+/*
+ * barrier.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+    if (omp_get_thread_num() == 0) {
+      var++;
+    }
+
+#pragma omp barrier
+
+    if (omp_get_thread_num() == 1) {
+      var++;
+    }
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/critical/critical.c

+/*
+ * critical.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+#pragma omp parallel num_threads(8) shared(var)
+  {
+#pragma omp critical
+    { var++; }
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 8);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/critical/lock-nested.c

+/*
+ * lock-nested.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+  omp_nest_lock_t lock;
+  omp_init_nest_lock(&lock);
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+    omp_set_nest_lock(&lock);
+    omp_set_nest_lock(&lock);
+    var++;
+    omp_unset_nest_lock(&lock);
+    omp_unset_nest_lock(&lock);
+  }
+
+  omp_destroy_nest_lock(&lock);
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/critical/lock.c

+/*
+ * lock.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+  omp_lock_t lock;
+  omp_init_lock(&lock);
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+    omp_set_lock(&lock);
+    var++;
+    omp_unset_lock(&lock);
+  }
+
+  omp_destroy_lock(&lock);
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/deflake.bash

+#!/usr/bin/env bash
+# This script is used to deflake inherently flaky archer tests.
+# It is invoked from lit tests as:
+# %deflake mybinary
+# which is then substituted by lit to:
+# $(dirname %s)/deflake.bash mybinary
+# The script runs the target program up to 10 times,
+# until it fails (i.e. produces a race report).
+
+for i in $(seq 1 10); do
+    OUT=`$@ 2>&1`
+    if [[ $? != 0 ]]; then
+  echo "$OUT"
+  exit 0
+    fi
+done
+exit 1

openmp/tools/archer/tests/lit.cfg

+# -*- Python -*- vim: set ft=python ts=4 sw=4 expandtab tw=79:
+# Configuration file for the 'lit' test runner.
+
+import os
+import re
+import subprocess
+import lit.formats
+
+# Tell pylint that we know config and lit_config exist somewhere.
+if 'PYLINT_IMPORT' in os.environ:
+    config = object()
+    lit_config = object()
+
+def append_dynamic_library_path(path):
+    if config.operating_system == 'Windows':
+        name = 'PATH'
+        sep = ';'
+    elif config.operating_system == 'Darwin':
+        name = 'DYLD_LIBRARY_PATH'
+        sep = ':'
+    else:
+        name = 'LD_LIBRARY_PATH'
+        sep = ':'
+    if name in config.environment:
+        config.environment[name] = path + sep + config.environment[name]
+    else:
+        config.environment[name] = path
+
+# name: The name of this test suite.
+config.name = 'libarcher'
+
+# suffixes: A list of file extensions to treat as test files.
+config.suffixes = ['.c', '.cpp']
+
+# test_source_root: The root path where tests are located.
+config.test_source_root = os.path.dirname(__file__)
+
+# test_exec_root: The root object directory where output is placed
+config.test_exec_root = config.libarcher_obj_root
+
+# test format
+config.test_format = lit.formats.ShTest()
+
+# compiler flags
+config.test_flags = " -I " + config.test_source_root + \
+    " -I " + config.omp_header_dir + \
+    " -L " + config.omp_library_dir + \
+    " -Wl,-rpath," + config.omp_library_dir + \
+    " " + config.test_extra_flags
+
+config.archer_flags = "-g -O1 -fsanitize=thread"
+
+
+# extra libraries
+libs = ""
+if config.has_libatomic:
+    libs += " -latomic"
+
+# Allow XFAIL to work
+config.target_triple = [ ]
+for feature in config.test_compiler_features:
+    config.available_features.add(feature)
+
+# Setup environment to find dynamic library at runtime
+append_dynamic_library_path(config.omp_library_dir)
+
+# Rpath modifications for Darwin
+if config.operating_system == 'Darwin':
+    config.test_flags += " -Wl,-rpath," + config.omp_library_dir
+
+# Find the SDK on Darwin
+if config.operating_system == 'Darwin':
+  cmd = subprocess.Popen(['xcrun', '--show-sdk-path'],
+                         stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+  out, err = cmd.communicate()
+  out = out.strip()
+  res = cmd.wait()
+  if res == 0 and out:
+    config.test_flags += " -isysroot " + out
+
+if 'Linux' in config.operating_system:
+    config.available_features.add("linux")
+
+# to run with icc INTEL_LICENSE_FILE must be set
+if 'INTEL_LICENSE_FILE' in os.environ:
+    config.environment['INTEL_LICENSE_FILE'] = os.environ['INTEL_LICENSE_FILE']
+
+# Race Tests
+config.substitutions.append(("%libarcher-compile-and-run-race", \
+    "%libarcher-compile && %libarcher-run-race"))
+config.substitutions.append(("%libarcher-compile-and-run", \
+                             "%libarcher-compile && %libarcher-run"))
+config.substitutions.append(("%libarcher-cxx-compile-and-run", \
+    "%libarcher-cxx-compile && %libarcher-run"))
+config.substitutions.append(("%libarcher-cxx-compile", \
+    "%clang-archerXX %openmp_flags %archer_flags %flags -std=c++11 %s -o %t" + libs))
+config.substitutions.append(("%libarcher-compile", \
+                             "%clang-archer %openmp_flags %archer_flags %flags %s -o %t" + libs))
+config.substitutions.append(("%libarcher-run-race", "%suppression %deflake %t 2>&1 | tee %t.log"))
+config.substitutions.append(("%libarcher-run", "%suppression %t 2>&1 | tee %t.log"))
+config.substitutions.append(("%clang-archerXX", config.test_cxx_compiler))
+config.substitutions.append(("%clang-archer", config.test_c_compiler))
+config.substitutions.append(("%openmp_flags", config.test_openmp_flags))
+config.substitutions.append(("%archer_flags", config.archer_flags))
+config.substitutions.append(("%flags", config.test_flags))
+config.substitutions.append(("%suppression", "env TSAN_OPTIONS='ignore_noninstrumented_modules=1'"))
+config.substitutions.append(("%deflake", os.path.join(os.path.dirname(__file__), "deflake.bash")))
+
+config.substitutions.append(("FileCheck", config.test_filecheck))
+config.substitutions.append(("%sort-threads", "sort --numeric-sort --stable"))
+if config.operating_system == 'Windows':
+    # No such environment variable on Windows.
+    config.substitutions.append(("%preload-tool", "true ||"))
+elif config.operating_system == 'Darwin':
+    config.substitutions.append(("%preload-tool", "env DYLD_INSERT_LIBRARIES=%T/tool.so"))
+else:
+    config.substitutions.append(("%preload-tool", "env LD_PRELOAD=%T/tool.so"))

openmp/tools/archer/tests/lit.site.cfg.in

+@AUTO_GEN_COMMENT@
+
+config.test_c_compiler = "@OPENMP_TEST_C_COMPILER@"
+config.test_cxx_compiler = "@OPENMP_TEST_CXX_COMPILER@"
+config.test_compiler_features = @OPENMP_TEST_COMPILER_FEATURES@
+config.test_filecheck = "@OPENMP_FILECHECK_EXECUTABLE@"
+config.test_openmp_flags = "@OPENMP_TEST_OPENMP_FLAGS@"
+config.test_extra_flags = "@OPENMP_TEST_FLAGS@"
+config.libomp_obj_root = "@CMAKE_CURRENT_BINARY_DIR@"
+config.omp_library_dir = "@LIBOMP_LIBRARY_DIR@"
+config.omp_header_dir = "@LIBOMP_INCLUDE_DIR@"
+config.operating_system = "@CMAKE_SYSTEM_NAME@"
+config.has_libatomic = @LIBOMP_HAVE_LIBATOMIC@
+
+config.test_archer_flags = "@OPENMP_TEST_ARCHER_FLAGS@"
+config.libarcher_obj_root = "@CMAKE_CURRENT_BINARY_DIR@"
+
+# Let the main config do the real work.
+lit_config.load_config(config, "@CMAKE_CURRENT_SOURCE_DIR@/lit.cfg")

openmp/tools/archer/tests/ompt/ompt-signal.h

+/*
+ * ompt-signal.h -- Header providing low-level synchronization for tests
+ */
+
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is a copy from runtime/test/ompt/
+//
+//===----------------------------------------------------------------------===//
+
+#if defined(WIN32) || defined(_WIN32)
+#include <windows.h>
+#define delay() Sleep(1);
+#else
+#include <unistd.h>
+#define delay(t) usleep(t);
+#endif
+
+// These functions are used to provide a signal-wait mechanism to enforce
+// expected scheduling for the test cases.
+// Conditional variable (s) needs to be shared! Initialize to 0
+
+#define OMPT_SIGNAL(s) ompt_signal(&s)
+// inline
+void ompt_signal(int *s) {
+#pragma omp atomic
+  (*s)++;
+}
+
+#define OMPT_WAIT(s, v) ompt_wait(&s, v)
+// wait for s >= v
+// inline
+void ompt_wait(int *s, int v) {
+  int wait = 0;
+  do {
+    delay(10);
+#pragma omp atomic read
+    wait = (*s);
+  } while (wait < v);
+}

openmp/tools/archer/tests/parallel/parallel-firstprivate.c

+/*
+ * parallel-firstprivate.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+#pragma omp parallel num_threads(2) firstprivate(var)
+  { var = 1; }
+
+  fprintf(stderr, "DONE\n");
+  // var should still be 0!
+  return var;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/parallel/parallel-simple.c

+/*
+ * parallel-simple.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+    if (omp_get_thread_num() == 1) {
+      var++;
+    }
+  } // implicit barrier
+
+  var++;
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/parallel/parallel-simple2.c

+/*
+ * parallel-simple2.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run  | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+// Create team of threads so that there is no implicit happens before
+// when creating the thread.
+#pragma omp parallel num_threads(2)
+  {}
+
+  var++;
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+    if (omp_get_thread_num() == 1) {
+      var++;
+    }
+  } // implicit barrier
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/races/critical-unrelated.c

+/*
+ * critical-unrelated.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+#pragma omp critical
+    {
+      // Dummy region.
+    }
+
+    var++;
+  }
+
+  fprintf(stderr, "DONE\n");
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}critical-unrelated.c:29
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}critical-unrelated.c:29
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/races/lock-nested-unrelated.c

+/*
+ * lock-nested-unrelated.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+  omp_nest_lock_t lock;
+  omp_init_nest_lock(&lock);
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+    omp_set_nest_lock(&lock);
+    omp_set_nest_lock(&lock);
+    // Dummy locking.
+    omp_unset_nest_lock(&lock);
+    omp_unset_nest_lock(&lock);
+
+    var++;
+  }
+
+  omp_destroy_nest_lock(&lock);
+
+  fprintf(stderr, "DONE\n");
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}lock-nested-unrelated.c:33
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}lock-nested-unrelated.c:33
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/races/lock-unrelated.c

+/*
+ * lock-unrelated.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+  omp_lock_t lock;
+  omp_init_lock(&lock);
+
+#pragma omp parallel num_threads(2) shared(var)
+  {
+    omp_set_lock(&lock);
+    // Dummy locking.
+    omp_unset_lock(&lock);
+
+    var++;
+  }
+
+  omp_destroy_lock(&lock);
+
+  int error = (var != 2);
+  fprintf(stderr, "DONE\n");
+  return error;
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}lock-unrelated.c:31
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}lock-unrelated.c:31
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/races/parallel-simple.c

+/*
+ * parallel-simple.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+#pragma omp parallel num_threads(2) shared(var)
+  { var++; }
+
+  int error = (var != 2);
+  fprintf(stderr, "DONE\n");
+  return error;
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}parallel-simple.c:23
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}parallel-simple.c:23
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/races/task-dependency.c

+/*
+ * task-deoendency.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp task shared(var, a) depend(out : var)
+    {
+      OMPT_SIGNAL(a);
+      var++;
+    }
+
+#pragma omp task shared(a) depend(in : var)
+    {
+      OMPT_SIGNAL(a);
+      OMPT_WAIT(a, 3);
+    }
+
+#pragma omp task shared(var) // depend(in: var) is missing here!
+    {
+      var++;
+      OMPT_SIGNAL(a);
+    }
+
+    // Give other thread time to steal the task.
+    OMPT_WAIT(a, 2);
+  }
+
+  int error = (var != 2);
+  fprintf(stderr, "DONE\n");
+  return error;
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}task-dependency.c:41
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}task-dependency.c:30
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/races/task-taskgroup-unrelated.c

+/*
+ * task-taskgroup-unrelated.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp task shared(var, a)
+    {
+      var++;
+      OMPT_SIGNAL(a);
+      // Give master thread time to execute the task in the taskgroup.
+      OMPT_WAIT(a, 2);
+    }
+
+#pragma omp taskgroup
+    {
+#pragma omp task if (0)
+      {
+        // Dummy task.
+      }
+
+      // Give other threads time to steal the tasks.
+      OMPT_WAIT(a, 1);
+      OMPT_SIGNAL(a);
+    }
+
+    var++;
+  }
+
+  int error = (var != 2);
+  fprintf(stderr, "DONE\n");
+  return error;
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}task-taskgroup-unrelated.c:46
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}task-taskgroup-unrelated.c:28
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/races/task-taskwait-nested.c

+/*
+ * task-taskwait-nested.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp task shared(var, a)
+    {
+#pragma omp task shared(var, a)
+      {
+        // wait for master to pass the taskwait
+        OMPT_SIGNAL(a);
+        OMPT_WAIT(a, 2);
+        var++;
+      }
+    }
+
+    // Give other thread time to steal the task and execute its child.
+    OMPT_WAIT(a, 1);
+
+// Only directly generated children are guaranteed to be executed.
+#pragma omp taskwait
+    OMPT_SIGNAL(a);
+    var++;
+  }
+
+  int error = (var != 2);
+  fprintf(stderr, "DONE\n");
+  return error;
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}task-taskwait-nested.c:34
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}task-taskwait-nested.c:44
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/races/task-two.c

+/*
+ * task-two.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run-race | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#define NUM_THREADS 2
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+  int i;
+
+#pragma omp parallel for num_threads(NUM_THREADS) shared(var) schedule(static, \
+                                                                       1)
+  for (i = 0; i < NUM_THREADS; i++) {
+#pragma omp task shared(var) if (0) // the task is inlined an executed locally
+    { var++; }
+  }
+
+  int error = (var != 2);
+  fprintf(stderr, "DONE\n");
+  return error;
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   {{(Write|Read)}} of size 4
+// CHECK-NEXT: #0 {{.*}}task-two.c:30
+// CHECK:   Previous write of size 4
+// CHECK-NEXT: #0 {{.*}}task-two.c:30
+// CHECK: DONE
+// CHECK: ThreadSanitizer: reported 1 warnings
+

openmp/tools/archer/tests/reduction/parallel-reduction-nowait.c

+/*
+ * parallel-reduction-nowait.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0, i;
+  int sum1 = 0;
+  int sum2 = 0;
+
+// Number of threads is empirical: We need enough threads so that
+// the reduction is really performed hierarchically in the barrier!
+#pragma omp parallel num_threads(5) reduction(+ : var)
+  {
+#pragma omp for schedule(static) nowait reduction(+ : sum1)
+    for (i = 0; i < 5; i++)
+      sum1 += i;
+#pragma omp for schedule(static) reduction(+ : sum2)
+    for (i = 0; i < 5; i++)
+      sum2 += i;
+
+    var = sum1 + sum2;
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 100);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/reduction/parallel-reduction.c

+/*
+ * parallel-reduction.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run| FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+
+// Number of threads is empirical: We need enough threads so that
+// the reduction is really performed hierarchically in the barrier!
+#pragma omp parallel num_threads(5) reduction(+ : var)
+  { var = 1; }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 5);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/task/task-barrier.c

+/*
+ * task-barrier.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+  {
+#pragma omp master
+    {
+#pragma omp task shared(var)
+      {
+        OMPT_SIGNAL(a);
+        var++;
+      }
+
+      // Give other thread time to steal the task.
+      OMPT_WAIT(a, 1);
+    }
+
+#pragma omp barrier
+
+#pragma omp master
+    { var++; }
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/task/task-create.c

+/*
+ * task-create.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+    var++;
+#pragma omp task shared(var, a)
+    {
+      var++;
+      OMPT_SIGNAL(a);
+    }
+
+    // Give other thread time to steal the task.
+    OMPT_WAIT(a, 1);
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/task/task-dependency.c

+/*
+ * task-dependency.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp task shared(var, a) depend(out : var)
+    {
+      var++;
+      OMPT_SIGNAL(a);
+    }
+
+#pragma omp task shared(var, a) depend(in : var)
+    { OMPT_WAIT(a, 2); }
+
+#pragma omp task shared(var, a) depend(in : var)
+    {
+      OMPT_SIGNAL(a);
+      var++;
+    }
+
+    // Give other thread time to steal the task.
+    OMPT_WAIT(a, 1);
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/task/task-taskgroup-nested.c

+/*
+ * task-taskgroup-nested.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp taskgroup
+    {
+#pragma omp task
+      {
+#pragma omp task shared(var, a)
+        {
+          var++;
+          OMPT_SIGNAL(a);
+        }
+      }
+
+      // Give other thread time to steal the task and execute its child.
+      OMPT_WAIT(a, 1);
+    }
+
+    var++;
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/task/task-taskgroup.c

+/*
+ * task-taskgroup.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp taskgroup
+    {
+#pragma omp task shared(var, a)
+      {
+        var++;
+        OMPT_SIGNAL(a);
+      }
+
+      // Give other thread time to steal the task.
+      OMPT_WAIT(a, 1);
+    }
+
+    var++;
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/task/task-taskwait-nested.c

+/*
+ * task-taskwait-nested.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp task
+    {
+#pragma omp task shared(var, a)
+      {
+        OMPT_SIGNAL(a);
+        delay(100);
+        var++;
+      }
+#pragma omp taskwait
+    }
+
+    // Give other thread time to steal the task and execute its child.
+    OMPT_WAIT(a, 1);
+
+#pragma omp taskwait
+    var++;
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/task/task-taskwait.c

+/*
+ * task-taskwait.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "ompt/ompt-signal.h"
+
+int main(int argc, char *argv[]) {
+  int var = 0, a = 0;
+
+#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp master
+  {
+#pragma omp task shared(var, a)
+    {
+      OMPT_SIGNAL(a);
+      OMPT_WAIT(a, 2);
+      delay(100);
+      var++;
+    }
+
+    // Give other thread time to steal the task.
+    OMPT_WAIT(a, 1);
+    OMPT_SIGNAL(a);
+#pragma omp taskwait
+    var++;
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE

openmp/tools/archer/tests/worksharing/ordered.c

+/*
+ * ordered.c -- Archer testcase
+ */
+
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+//
+// See tools/archer/LICENSE.txt for details.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+// RUN: %libarcher-compile-and-run | FileCheck %s
+#include <omp.h>
+#include <stdio.h>
+
+#define NUM_THREADS 2
+
+int main(int argc, char *argv[]) {
+  int var = 0;
+  int i;
+
+#pragma omp parallel for ordered num_threads(NUM_THREADS) shared(var)
+  for (i = 0; i < NUM_THREADS; i++) {
+#pragma omp ordered
+    { var++; }
+  }
+
+  fprintf(stderr, "DONE\n");
+  int error = (var != 2);
+  return error;
+}
+
+// CHECK-NOT: ThreadSanitizer: data race
+// CHECK-NOT: ThreadSanitizer: reported
+// CHECK: DONE