[Libomptarget] Rework Record & Replay to be a plugin member

Summary:
Previously, the R&R support was global state initialized by a global
constructor. This is bad because it prevents us from adequately
constraining the lifetime of the library. Additionally, we want to
minimize the amount of global state floating around.

This patch moves the R&R support into a plugin member like everything
else. This means there will be multiple copies of the R&R implementation
floating around, but this was already the case given the fact that we
currently handle everything with dynamic libraries.

Author: jhuber6

offload/plugins-nextgen/common/include/PluginInterface.h

@@ -54,6 +54,7 @@ namespace plugin {
 struct GenericPluginTy;
 struct GenericKernelTy;
 struct GenericDeviceTy;
+struct RecordReplayTy;
 
 /// Class that wraps the __tgt_async_info to simply its usage. In case the
 /// object is constructed without a valid __tgt_async_info, the object will use
@@ -958,7 +959,8 @@ struct GenericPluginTy {
 
   /// Construct a plugin instance.
   GenericPluginTy(Triple::ArchType TA)
-      : GlobalHandler(nullptr), JIT(TA), RPCServer(nullptr) {}
+      : GlobalHandler(nullptr), JIT(TA), RPCServer(nullptr),
+        RecordReplay(nullptr) {}
 
   virtual ~GenericPluginTy() {}
 
@@ -1027,6 +1029,12 @@ struct GenericPluginTy {
     return *RPCServer;
   }
 
+  /// Get a reference to the record and replay interface for the plugin.
+  RecordReplayTy &getRecordReplay() {
+    assert(RecordReplay && "RR interface not initialized");
+    return *RecordReplay;
+  }
+
   /// Initialize a device within the plugin.
   Error initDevice(int32_t DeviceId);
 
@@ -1204,6 +1212,9 @@ struct GenericPluginTy {
 
   /// The interface between the plugin and the GPU for host services.
   RPCServerTy *RPCServer;
+
+  /// The interface between the plugin and the GPU for host services.
+  RecordReplayTy *RecordReplay;
 };
 
 namespace Plugin {

offload/plugins-nextgen/common/src/PluginInterface.cpp

@@ -39,6 +39,7 @@ using namespace target;
 using namespace plugin;
 
 // TODO: Fix any thread safety issues for multi-threaded kernel recording.
+namespace llvm::omp::target::plugin {
 struct RecordReplayTy {
 
   // Describes the state of the record replay mechanism.
@@ -358,8 +359,7 @@ struct RecordReplayTy {
     }
   }
 };
-
-static RecordReplayTy RecordReplay;
+} // namespace llvm::omp::target::plugin
 
 // Extract the mapping of host function pointers to device function pointers
 // from the entry table. Functions marked as 'indirect' in OpenMP will have
@@ -470,7 +470,7 @@ GenericKernelTy::getKernelLaunchEnvironment(
   // Ctor/Dtor have no arguments, replaying uses the original kernel launch
   // environment. Older versions of the compiler do not generate a kernel
   // launch environment.
-  if (RecordReplay.isReplaying() ||
+  if (GenericDevice.Plugin.getRecordReplay().isReplaying() ||
       Version < OMP_KERNEL_ARG_MIN_VERSION_WITH_DYN_PTR)
     return nullptr;
 
@@ -559,6 +559,7 @@ Error GenericKernelTy::launch(GenericDeviceTy &GenericDevice, void **ArgPtrs,
 
   // Record the kernel description after we modified the argument count and num
   // blocks/threads.
+  RecordReplayTy &RecordReplay = GenericDevice.Plugin.getRecordReplay();
   if (RecordReplay.isRecording()) {
     RecordReplay.saveImage(getName(), getImage());
     RecordReplay.saveKernelInput(getName(), getImage());
@@ -833,6 +834,7 @@ Error GenericDeviceTy::deinit(GenericPluginTy &Plugin) {
     delete MemoryManager;
   MemoryManager = nullptr;
 
+  RecordReplayTy &RecordReplay = Plugin.getRecordReplay();
   if (RecordReplay.isRecordingOrReplaying())
     RecordReplay.deinit();
 
@@ -886,7 +888,8 @@ GenericDeviceTy::loadBinary(GenericPluginTy &Plugin,
     return std::move(Err);
 
   // Setup the global device memory pool if needed.
-  if (!RecordReplay.isReplaying() && shouldSetupDeviceMemoryPool()) {
+  if (!Plugin.getRecordReplay().isReplaying() &&
+      shouldSetupDeviceMemoryPool()) {
     uint64_t HeapSize;
     auto SizeOrErr = getDeviceHeapSize(HeapSize);
     if (SizeOrErr) {
@@ -1301,8 +1304,8 @@ Expected<void *> GenericDeviceTy::dataAlloc(int64_t Size, void *HostPtr,
                                             TargetAllocTy Kind) {
   void *Alloc = nullptr;
 
-  if (RecordReplay.isRecordingOrReplaying())
-    return RecordReplay.alloc(Size);
+  if (Plugin.getRecordReplay().isRecordingOrReplaying())
+    return Plugin.getRecordReplay().alloc(Size);
 
   switch (Kind) {
   case TARGET_ALLOC_DEFAULT:
@@ -1338,7 +1341,7 @@ Expected<void *> GenericDeviceTy::dataAlloc(int64_t Size, void *HostPtr,
 
 Error GenericDeviceTy::dataDelete(void *TgtPtr, TargetAllocTy Kind) {
   // Free is a noop when recording or replaying.
-  if (RecordReplay.isRecordingOrReplaying())
+  if (Plugin.getRecordReplay().isRecordingOrReplaying())
     return Plugin::success();
 
   int Res;
@@ -1405,7 +1408,8 @@ Error GenericDeviceTy::launchKernel(void *EntryPtr, void **ArgPtrs,
                                     KernelArgsTy &KernelArgs,
                                     __tgt_async_info *AsyncInfo) {
   AsyncInfoWrapperTy AsyncInfoWrapper(
-      *this, RecordReplay.isRecordingOrReplaying() ? nullptr : AsyncInfo);
+      *this,
+      Plugin.getRecordReplay().isRecordingOrReplaying() ? nullptr : AsyncInfo);
 
   GenericKernelTy &GenericKernel =
       *reinterpret_cast<GenericKernelTy *>(EntryPtr);
@@ -1416,6 +1420,7 @@ Error GenericDeviceTy::launchKernel(void *EntryPtr, void **ArgPtrs,
   // 'finalize' here to guarantee next record-replay actions are in-sync
   AsyncInfoWrapper.finalize(Err);
 
+  RecordReplayTy &RecordReplay = Plugin.getRecordReplay();
   if (RecordReplay.isRecordingOrReplaying() &&
       RecordReplay.isSaveOutputEnabled())
     RecordReplay.saveKernelOutputInfo(GenericKernel.getName());
@@ -1503,6 +1508,9 @@ Error GenericPluginTy::init() {
   RPCServer = new RPCServerTy(*this);
   assert(RPCServer && "Invalid RPC server");
 
+  RecordReplay = new RecordReplayTy();
+  assert(RecordReplay && "Invalid RR interface");
+
   return Plugin::success();
 }
 
@@ -1523,6 +1531,9 @@ Error GenericPluginTy::deinit() {
   if (RPCServer)
     delete RPCServer;
 
+  if (RecordReplay)
+    delete RecordReplay;
+
   // Perform last deinitializations on the plugin.
   return deinitImpl();
 }
@@ -1633,12 +1644,12 @@ int32_t GenericPluginTy::initialize_record_replay(int32_t DeviceId,
       isRecord ? RecordReplayTy::RRStatusTy::RRRecording
                : RecordReplayTy::RRStatusTy::RRReplaying;
 
-  if (auto Err = RecordReplay.init(&Device, MemorySize, VAddr, Status,
-                                   SaveOutput, ReqPtrArgOffset)) {
+  if (auto Err = RecordReplay->init(&Device, MemorySize, VAddr, Status,
+                                    SaveOutput, ReqPtrArgOffset)) {
     REPORT("WARNING RR did not intialize RR-properly with %lu bytes"
            "(Error: %s)\n",
            MemorySize, toString(std::move(Err)).data());
-    RecordReplay.setStatus(RecordReplayTy::RRStatusTy::RRDeactivated);
+    RecordReplay->setStatus(RecordReplayTy::RRStatusTy::RRDeactivated);
 
     if (!isRecord) {
       return OFFLOAD_FAIL;
@@ -1982,6 +1993,7 @@ int32_t GenericPluginTy::get_global(__tgt_device_binary Binary, uint64_t Size,
   assert(DevicePtr && "Invalid device global's address");
 
   // Save the loaded globals if we are recording.
+  RecordReplayTy &RecordReplay = Device.Plugin.getRecordReplay();
   if (RecordReplay.isRecording())
     RecordReplay.addEntry(Name, Size, *DevicePtr);