[XRay][compiler-rt] Enable the XRay compiler-rt unit tests.

[dberris]

Summary

Before this change we seemed to not be running the unit tests, and therefore we
set out to run them. In the process of making this happen we found a divergence
between the implementation and the tests.

This includes changes to both the CMake files as well as the implementation and
headers of the XRay runtime. We've also updated documentation on the changed
functions.

[dberris]

• fixup: revert changes to unrelated test

compiler-rt/trunk/lib/xray/tests/CMakeLists.txt

 include_directories(..)
 
 add_custom_target(XRayUnitTests)
 set_target_properties(XRayUnitTests PROPERTIES FOLDER "XRay unittests")
 
 set(XRAY_UNITTEST_CFLAGS
   ${XRAY_CFLAGS}
   ${COMPILER_RT_UNITTEST_CFLAGS}
   ${COMPILER_RT_GTEST_CFLAGS}
   -I${COMPILER_RT_SOURCE_DIR}/include
   -I${COMPILER_RT_SOURCE_DIR}/lib/xray
   -I${COMPILER_RT_SOURCE_DIR}/lib)
 
-macro(add_xray_unittest testname)
-  set(XRAY_TEST_ARCH ${XRAY_SUPPORTED_ARCH})
+macro(add_xray_unittest testname)
   cmake_parse_arguments(TEST "" "" "SOURCES;HEADERS" ${ARGN})
-  # FIXME: Figure out how to run even just the unit tests on APPLE.
   if(UNIX AND NOT APPLE)
     foreach(arch ${XRAY_TEST_ARCH})
       set(TEST_OBJECTS)
       generate_compiler_rt_tests(TEST_OBJECTS
-        XRayUnitTests "${testname}-${arch}" "${arch}"
+        XRayUnitTests "${testname}-${arch}-Test" "${arch}"
         SOURCES ${TEST_SOURCES} ${COMPILER_RT_GTEST_SOURCE}
-        DEPS gtest_main xray
+        DEPS gtest xray
         CFLAGS ${XRAY_UNITTEST_CFLAGS}
-        LINK_FLAGS
+        LINK_FLAGS -fxray-instrument
+          ${TARGET_LINK_FLAGS}
           -lstdc++ -lm ${CMAKE_THREAD_LIBS_INIT}
           -lpthread
-          -L${COMPILER_RT_LIBRARY_OUTPUT_DIR} -lclang_rt.xray-${arch}
           -ldl -lrt)
     endforeach()
   endif()
 endmacro()
 
 if(COMPILER_RT_CAN_EXECUTE_TESTS)
   add_subdirectory(unit)
 endif()

compiler-rt/trunk/lib/xray/tests/unit/buffer_queue_test.cc

TEST(BufferQueueTest, ErrorsWhenFinalising) {
   bool Success = false;
   BufferQueue Buffers(kSize, 2, Success);
   ASSERT_TRUE(Success);
   BufferQueue::Buffer Buf;
   ASSERT_EQ(Buffers.getBuffer(Buf), BufferQueue::ErrorCode::Ok);
   ASSERT_NE(nullptr, Buf.Buffer);
   ASSERT_EQ(Buffers.finalize(), BufferQueue::ErrorCode::Ok);
   BufferQueue::Buffer OtherBuf;
-  ASSERT_EQ(BufferQueue::ErrorCode::AlreadyFinalized,
+  ASSERT_EQ(BufferQueue::ErrorCode::QueueFinalizing,
             Buffers.getBuffer(OtherBuf));
-  ASSERT_EQ(BufferQueue::ErrorCode::AlreadyFinalized,
+  ASSERT_EQ(BufferQueue::ErrorCode::QueueFinalizing,
             Buffers.finalize());
   ASSERT_EQ(Buffers.releaseBuffer(Buf), BufferQueue::ErrorCode::Ok);
 }
 
 TEST(BufferQueueTest, MultiThreaded) {
   bool Success = false;
   BufferQueue Buffers(kSize, 100, Success);
   ASSERT_TRUE(Success);

compiler-rt/trunk/lib/xray/tests/unit/fdr_logging_test.cc

TEST(FDRLoggingTest, Simple) {
   ASSERT_NE(Options.Fd, -1);
   ASSERT_EQ(fdrLoggingInit(kBufferSize, kBufferMax, &Options,
                             sizeof(FDRLoggingOptions)),
             XRayLogInitStatus::XRAY_LOG_INITIALIZED);
   fdrLoggingHandleArg0(1, XRayEntryType::ENTRY);
   fdrLoggingHandleArg0(1, XRayEntryType::EXIT);
   ASSERT_EQ(fdrLoggingFinalize(), XRayLogInitStatus::XRAY_LOG_FINALIZED);
   ASSERT_EQ(fdrLoggingFlush(), XRayLogFlushStatus::XRAY_LOG_FLUSHED);
-  ASSERT_EQ(fdrLoggingReset(), XRayLogInitStatus::XRAY_LOG_UNINITIALIZED);
 
   // To do this properly, we have to close the file descriptor then re-open the
   // file for reading this time.
   ASSERT_EQ(close(Options.Fd), 0);
   int Fd = open(TmpFilename, O_RDONLY);
   ASSERT_NE(-1, Fd);
   ScopedFileCloserAndDeleter Guard(Fd, TmpFilename);
   auto Size = lseek(Fd, 0, SEEK_END);
ASSERT_EQ(fdrLoggingInit(kBufferSize, kBufferMax, &Options,
                             sizeof(FDRLoggingOptions)),
             XRayLogInitStatus::XRAY_LOG_INITIALIZED);
   for (uint64_t I = 0; I < 100; ++I) {
     fdrLoggingHandleArg0(1, XRayEntryType::ENTRY);
     fdrLoggingHandleArg0(1, XRayEntryType::EXIT);
   }
   ASSERT_EQ(fdrLoggingFinalize(), XRayLogInitStatus::XRAY_LOG_FINALIZED);
   ASSERT_EQ(fdrLoggingFlush(), XRayLogFlushStatus::XRAY_LOG_FLUSHED);
-  ASSERT_EQ(fdrLoggingReset(), XRayLogInitStatus::XRAY_LOG_UNINITIALIZED);
 
   // To do this properly, we have to close the file descriptor then re-open the
   // file for reading this time.
   ASSERT_EQ(close(Options.Fd), 0);
   int Fd = open(TmpFilename, O_RDONLY);
   ASSERT_NE(-1, Fd);
   ScopedFileCloserAndDeleter Guard(Fd, TmpFilename);
   auto Size = lseek(Fd, 0, SEEK_END);

compiler-rt/trunk/lib/xray/xray_buffer_queue.h

public:
   /// Updates |Buf| to contain the pointer to an appropriate buffer. Returns an
   /// error in case there are no available buffers to return when we will run
   /// over the upper bound for the total buffers.
   ///
   /// Requirements:
   ///   - BufferQueue is not finalising.
   ///
   /// Returns:
-  ///   - std::errc::not_enough_memory on exceeding MaxSize.
-  ///   - no error when we find a Buffer.
-  ///   - std::errc::state_not_recoverable on finalising BufferQueue.
+  ///   - ErrorCode::NotEnoughMemory on exceeding MaxSize.
+  ///   - ErrorCode::Ok when we find a Buffer.
+  ///   - ErrorCode::QueueFinalizing or ErrorCode::AlreadyFinalized on
+  ///     a finalizing/finalized BufferQueue.
   ErrorCode getBuffer(Buffer &Buf);
 
   /// Updates |Buf| to point to nullptr, with size 0.
   ///
   /// Returns:
-  ///   - ...
+  ///   - ErrorCode::Ok when we successfully release the buffer.
+  ///   - ErrorCode::UnrecognizedBuffer for when this BufferQueue does not own
+  ///     the buffer being released.
   ErrorCode releaseBuffer(Buffer &Buf);
 
   bool finalizing() const {
     return __sanitizer::atomic_load(&Finalizing,
                                     __sanitizer::memory_order_acquire);
   }
 
   /// Returns the configured size of the buffers in the buffer queue.
   size_t ConfiguredBufferSize() const { return BufferSize; }
 
   /// Sets the state of the BufferQueue to finalizing, which ensures that:
   ///
   ///   - All subsequent attempts to retrieve a Buffer will fail.
   ///   - All releaseBuffer operations will not fail.
   ///
   /// After a call to finalize succeeds, all subsequent calls to finalize will
-  /// fail with std::errc::state_not_recoverable.
+  /// fail with ErrorCode::QueueFinalizing.
   ErrorCode finalize();
 
   /// Applies the provided function F to each Buffer in the queue, only if the
   /// Buffer is marked 'used' (i.e. has been the result of getBuffer(...) and a
-  /// releaseBuffer(...) operation.
+  /// releaseBuffer(...) operation).
   template <class F> void apply(F Fn) {
     __sanitizer::BlockingMutexLock G(&Mutex);
     for (const auto &T : Buffers) {
       if (std::get<1>(T))
         Fn(std::get<0>(T));
     }
   }
 
   // Cleans up allocated buffers.
   ~BufferQueue();
 };
 
 } // namespace __xray
 
 #endif // XRAY_BUFFER_QUEUE_H

compiler-rt/trunk/test/xray/Unit/lit.site.cfg.in

 @LIT_SITE_CFG_IN_HEADER@
 
 import os
 
 # Load common config for all compiler-rt unit tests.
 lit_config.load_config(config, "@COMPILER_RT_BINARY_DIR@/unittests/lit.common.unit.configured")
 
 # Setup config name.
 config.name = 'XRay-Unit'
 
 config.test_exec_root = "@COMPILER_RT_BINARY_DIR@/lib/xray/tests"
 config.test_source_root = config.test_exec_root
 
 # Do not patch the XRay unit tests pre-main, and also make the error logging
 # verbose to get a more accurate error logging mechanism.
-config.environment['XRAY_OPTIONS'] = 'patch_premain=false verbose=1'
+config.environment['XRAY_OPTIONS'] = 'patch_premain=false'

compiler-rt/trunk/test/xray/lit.site.cfg.in

 # standalone build.
 if config.built_with_llvm:
   config.available_features.add('built-in-llvm-tree')
 
 # Load common config for all compiler-rt lit tests
 lit_config.load_config(config, "@COMPILER_RT_BINARY_DIR@/test/lit.common.configured")
 
 # Load tool-specific config that would do the real work.
-lit_config.load_config(config, "@XRAY_LIT_SOURCE_DIR@/lit.cfg")
+lit_config.load_config(config, "@CMAKE_CURRENT_SOURCE_DIR@/lit.cfg")