[Libomptarget][NFCI] Remove caching of created ELF files

openmp/libomptarget/plugins-nextgen/common/include/GlobalHandler.h

@@ -89,9 +89,6 @@ template <typename Ty> class StaticGlobalTy : public GlobalTy {
 /// global metadata (size, addr) from the device.
 /// \see getGlobalMetadataFromDevice
 class GenericGlobalHandlerTy {
-  /// Map to store the ELF object files that have been loaded.
-  llvm::DenseMap<int32_t, ELF64LEObjectFile> ELFObjectFiles;
-
   /// Actually move memory between host and device. See readGlobalFromDevice and
   /// writeGlobalToDevice for the interface description.
   Error moveGlobalBetweenDeviceAndHost(GenericDeviceTy &Device,
@@ -109,10 +106,8 @@ class GenericGlobalHandlerTy {
 public:
   virtual ~GenericGlobalHandlerTy() {}
 
-  /// Get the cached ELF64LEObjectFile previosuly created for a specific
-  /// device image or create it if did not exist.
-  const ELF64LEObjectFile *
-  getOrCreateELFObjectFile(const GenericDeviceTy &Device, DeviceImageTy &Image);
+  /// Helper function for getting an ELF from a device image.
+  Expected<ELF64LEObjectFile> getELFObjectFile(DeviceImageTy &Image);
 
   /// Returns whether the symbol named \p SymName is present in the given \p
   /// Image.

openmp/libomptarget/plugins-nextgen/common/src/GlobalHandler.cpp

@@ -25,29 +25,14 @@ using namespace omp;
 using namespace target;
 using namespace plugin;
 
-const ELF64LEObjectFile *
-GenericGlobalHandlerTy::getOrCreateELFObjectFile(const GenericDeviceTy &Device,
-                                                 DeviceImageTy &Image) {
+Expected<ELF64LEObjectFile>
+GenericGlobalHandlerTy::getELFObjectFile(DeviceImageTy &Image) {
+  assert(utils::elf::isELF(Image.getMemoryBuffer().getBuffer()) &&
+         "Input is not an ELF file");
 
-  auto Search = ELFObjectFiles.find(Image.getId());
-  if (Search != ELFObjectFiles.end())
-    // The ELF object file was already there.
-    return &Search->second;
-
-  // The ELF object file we are checking is not created yet.
   Expected<ELF64LEObjectFile> ElfOrErr =
       ELF64LEObjectFile::create(Image.getMemoryBuffer());
-  if (!ElfOrErr) {
-    consumeError(ElfOrErr.takeError());
-    return nullptr;
-  }
-
-  auto Result =
-      ELFObjectFiles.try_emplace(Image.getId(), std::move(ElfOrErr.get()));
-  assert(Result.second && "Map insertion failed");
-  assert(Result.first != ELFObjectFiles.end() && "Map insertion failed");
-
-  return &Result.first->second;
+  return ElfOrErr;
 }
 
 Error GenericGlobalHandlerTy::moveGlobalBetweenDeviceAndHost(
@@ -83,7 +68,8 @@ Error GenericGlobalHandlerTy::moveGlobalBetweenDeviceAndHost(
       return Err;
   }
 
-  DP("Succesfully %s %u bytes associated with global symbol '%s' %s the device "
+  DP("Succesfully %s %u bytes associated with global symbol '%s' %s the "
+     "device "
      "(%p -> %p).\n",
      Device2Host ? "read" : "write", HostGlobal.getSize(),
      HostGlobal.getName().data(), Device2Host ? "from" : "to",
@@ -98,12 +84,14 @@ bool GenericGlobalHandlerTy::isSymbolInImage(GenericDeviceTy &Device,
   // Get the ELF object file for the image. Notice the ELF object may already
   // be created in previous calls, so we can reuse it. If this is unsuccessful
   // just return false as we couldn't find it.
-  const ELF64LEObjectFile *ELFObj = getOrCreateELFObjectFile(Device, Image);
-  if (!ELFObj)
+  auto ELFObjOrErr = getELFObjectFile(Image);
+  if (!ELFObjOrErr) {
+    consumeError(ELFObjOrErr.takeError());
     return false;
+  }
 
   // Search the ELF symbol using the symbol name.
-  auto SymOrErr = utils::elf::getSymbol(*ELFObj, SymName);
+  auto SymOrErr = utils::elf::getSymbol(*ELFObjOrErr, SymName);
   if (!SymOrErr) {
     consumeError(SymOrErr.takeError());
     return false;
@@ -117,10 +105,9 @@ Error GenericGlobalHandlerTy::getGlobalMetadataFromImage(
 
   // Get the ELF object file for the image. Notice the ELF object may already
   // be created in previous calls, so we can reuse it.
-  const ELF64LEObjectFile *ELFObj = getOrCreateELFObjectFile(Device, Image);
+  auto ELFObj = getELFObjectFile(Image);
   if (!ELFObj)
-    return Plugin::error("Unable to create ELF object for image %p",
-                         Image.getStart());
+    return ELFObj.takeError();
 
   // Search the ELF symbol using the symbol name.
   auto SymOrErr = utils::elf::getSymbol(*ELFObj, ImageGlobal.getName());

openmp/libomptarget/plugins-nextgen/cuda/src/rtl.cpp

@@ -1063,15 +1063,13 @@ struct CUDADeviceTy : public GenericDeviceTy {
     // automatically so we must create it ourselves. The backend will emit
     // several globals that contain function pointers we can call. These are
     // prefixed with a known name due to Nvidia's lack of section support.
-    const ELF64LEObjectFile *ELFObj =
-        Handler.getOrCreateELFObjectFile(*this, Image);
-    if (!ELFObj)
-      return Plugin::error("Unable to create ELF object for image %p",
-                           Image.getStart());
+    auto ELFObjOrErr = Handler.getELFObjectFile(Image);
+    if (!ELFObjOrErr)
+      return ELFObjOrErr.takeError();
 
     // Search for all symbols that contain a constructor or destructor.
     SmallVector<std::pair<StringRef, uint16_t>> Funcs;
-    for (ELFSymbolRef Sym : ELFObj->symbols()) {
+    for (ELFSymbolRef Sym : ELFObjOrErr->symbols()) {
       auto NameOrErr = Sym.getName();
       if (!NameOrErr)
         return NameOrErr.takeError();