[OpenMP] Replaced mutex lock/unlock in target with std::lock_guard

Reviewed By: ye-luo

Differential Revision: https://reviews.llvm.org/D84799

openmp/libomptarget/src/omptarget.cpp

@@ -722,38 +722,38 @@ int target(int64_t DeviceId, void *HostPtr, int32_t ArgNum, void **ArgBases,
   // Find the table information in the map or look it up in the translation
   // tables.
   TableMap *TM = 0;
-  TblMapMtx->lock();
-  HostPtrToTableMapTy::iterator TableMapIt = HostPtrToTableMap->find(HostPtr);
-  if (TableMapIt == HostPtrToTableMap->end()) {
-    // We don't have a map. So search all the registered libraries.
-    TrlTblMtx->lock();
-    for (HostEntriesBeginToTransTableTy::iterator
-             II = HostEntriesBeginToTransTable->begin(),
-             IE = HostEntriesBeginToTransTable->end();
-         !TM && II != IE; ++II) {
-      // get the translation table (which contains all the good info).
-      TranslationTable *TransTable = &II->second;
-      // iterate over all the host table entries to see if we can locate the
-      // host_ptr.
-      __tgt_offload_entry *Begin = TransTable->HostTable.EntriesBegin;
-      __tgt_offload_entry *End = TransTable->HostTable.EntriesEnd;
-      __tgt_offload_entry *Cur = Begin;
-      for (uint32_t I = 0; Cur < End; ++Cur, ++I) {
-        if (Cur->addr != HostPtr)
-          continue;
-        // we got a match, now fill the HostPtrToTableMap so that we
-        // may avoid this search next time.
-        TM = &(*HostPtrToTableMap)[HostPtr];
-        TM->Table = TransTable;
-        TM->Index = I;
-        break;
+  {
+    std::lock_guard<std::mutex> TblMapLock(*TblMapMtx);
+    HostPtrToTableMapTy::iterator TableMapIt = HostPtrToTableMap->find(HostPtr);
+    if (TableMapIt == HostPtrToTableMap->end()) {
+      // We don't have a map. So search all the registered libraries.
+      std::lock_guard<std::mutex> TrlTblLock(*TrlTblMtx);
+      for (HostEntriesBeginToTransTableTy::iterator
+               II = HostEntriesBeginToTransTable->begin(),
+               IE = HostEntriesBeginToTransTable->end();
+           !TM && II != IE; ++II) {
+        // get the translation table (which contains all the good info).
+        TranslationTable *TransTable = &II->second;
+        // iterate over all the host table entries to see if we can locate the
+        // host_ptr.
+        __tgt_offload_entry *Begin = TransTable->HostTable.EntriesBegin;
+        __tgt_offload_entry *End = TransTable->HostTable.EntriesEnd;
+        __tgt_offload_entry *Cur = Begin;
+        for (uint32_t I = 0; Cur < End; ++Cur, ++I) {
+          if (Cur->addr != HostPtr)
+            continue;
+          // we got a match, now fill the HostPtrToTableMap so that we
+          // may avoid this search next time.
+          TM = &(*HostPtrToTableMap)[HostPtr];
+          TM->Table = TransTable;
+          TM->Index = I;
+          break;
+        }
       }
+    } else {
+      TM = &TableMapIt->second;
     }
-    TrlTblMtx->unlock();
-  } else {
-    TM = &TableMapIt->second;
   }
-  TblMapMtx->unlock();
 
   // No map for this host pointer found!
   if (!TM) {
@@ -763,11 +763,13 @@ int target(int64_t DeviceId, void *HostPtr, int32_t ArgNum, void **ArgBases,
   }
 
   // get target table.
-  TrlTblMtx->lock();
-  assert(TM->Table->TargetsTable.size() > (size_t)DeviceId &&
-         "Not expecting a device ID outside the table's bounds!");
-  __tgt_target_table *TargetTable = TM->Table->TargetsTable[DeviceId];
-  TrlTblMtx->unlock();
+  __tgt_target_table *TargetTable = nullptr;
+  {
+    std::lock_guard<std::mutex> TrlTblLock(*TrlTblMtx);
+    assert(TM->Table->TargetsTable.size() > (size_t)DeviceId &&
+           "Not expecting a device ID outside the table's bounds!");
+    TargetTable = TM->Table->TargetsTable[DeviceId];
+  }
   assert(TargetTable && "Global data has not been mapped\n");
 
   __tgt_async_info AsyncInfo;
@@ -899,14 +901,15 @@ int target(int64_t DeviceId, void *HostPtr, int32_t ArgNum, void **ArgBases,
 
   // Pop loop trip count
   uint64_t LoopTripCount = 0;
-  TblMapMtx->lock();
-  auto I = Device.LoopTripCnt.find(__kmpc_global_thread_num(NULL));
-  if (I != Device.LoopTripCnt.end()) {
-    LoopTripCount = I->second;
-    Device.LoopTripCnt.erase(I);
-    DP("loop trip count is %lu.\n", LoopTripCount);
+  {
+    std::lock_guard<std::mutex> TblMapLock(*TblMapMtx);
+    auto I = Device.LoopTripCnt.find(__kmpc_global_thread_num(NULL));
+    if (I != Device.LoopTripCnt.end()) {
+      LoopTripCount = I->second;
+      Device.LoopTripCnt.erase(I);
+      DP("loop trip count is %lu.\n", LoopTripCount);
+    }
   }
-  TblMapMtx->unlock();
 
   // Launch device execution.
   DP("Launching target execution %s with pointer " DPxMOD " (index=%d).\n",