[Offload] Do not load images from the same descriptor on the same device

offload/libomptarget/PluginManager.cpp

@@ -202,9 +202,10 @@ void PluginManager::registerLib(__tgt_bin_desc *Desc) {
     PM->addDeviceImage(*Desc, Desc->DeviceImages[i]);
 
   // Register the images with the RTLs that understand them, if any.
-  for (DeviceImageTy &DI : PM->deviceImages()) {
+  llvm::DenseMap<GenericPluginTy *, llvm::DenseSet<int32_t>> UsedDevices;
+  for (int32_t i = 0; i < Desc->NumDeviceImages; ++i) {
     // Obtain the image and information that was previously extracted.
-    __tgt_device_image *Img = &DI.getExecutableImage();
+    __tgt_device_image *Img = &Desc->DeviceImages[i];
 
     GenericPluginTy *FoundRTL = nullptr;
 
@@ -223,6 +224,17 @@ void PluginManager::registerLib(__tgt_bin_desc *Desc) {
       }
 
       for (int32_t DeviceId = 0; DeviceId < R.number_of_devices(); ++DeviceId) {
+        // We only want a single matching image to be registered for each binary
+        // descriptor. This prevents multiple of the same image from being
+        // registered for the same device in the case that they are mutually
+        // compatible, such as sm_80 and sm_89.
+        if (UsedDevices[&R].contains(DeviceId)) {
+          DP("Image " DPxMOD
+             " is a duplicate, not loaded on RTL %s device %d!\n",
+             DPxPTR(Img->ImageStart), R.getName(), DeviceId);
+          continue;
+        }
+
         if (!R.is_device_compatible(DeviceId, Img))
           continue;
 
@@ -262,6 +274,7 @@ void PluginManager::registerLib(__tgt_bin_desc *Desc) {
         TT.TargetsImages[UserId] = Img;
         TT.TargetsTable[UserId] = nullptr;
 
+        UsedDevices[&R].insert(DeviceId);
         PM->UsedImages.insert(Img);
         FoundRTL = &R;