[OpenMP][OpenMPIRBuilder] Migrate loadOffloadInfoMetadata from clang to OMPIRbuilder

This patch moves the implementation of the loadOffloadInfoMetadata to the OMPIRbuilder.

Differential Revision: https://reviews.llvm.org/D136872

Author: TIFitis

clang/lib/CodeGen/CGOpenMPRuntime.cpp

@@ -3171,52 +3171,7 @@ void CGOpenMPRuntime::loadOffloadInfoMetadata() {
     return;
   }
 
-  llvm::NamedMDNode *MD = ME.get()->getNamedMetadata("omp_offload.info");
-  if (!MD)
-    return;
-
-  for (llvm::MDNode *MN : MD->operands()) {
-    auto &&GetMDInt = [MN](unsigned Idx) {
-      auto *V = cast<llvm::ConstantAsMetadata>(MN->getOperand(Idx));
-      return cast<llvm::ConstantInt>(V->getValue())->getZExtValue();
-    };
-
-    auto &&GetMDString = [MN](unsigned Idx) {
-      auto *V = cast<llvm::MDString>(MN->getOperand(Idx));
-      return V->getString();
-    };
-
-    switch (GetMDInt(0)) {
-    default:
-      llvm_unreachable("Unexpected metadata!");
-      break;
-    case llvm::OffloadEntriesInfoManager::OffloadEntryInfo::
-        OffloadingEntryInfoTargetRegion: {
-      assert(CGM.getLangOpts().OpenMPIsDevice && "Initialization of entries is "
-                                                 "only required for the "
-                                                 "device code generation.");
-      llvm::TargetRegionEntryInfo EntryInfo(/*ParentName=*/GetMDString(3),
-                                            /*DeviceID=*/GetMDInt(1),
-                                            /*FileID=*/GetMDInt(2),
-                                            /*Line=*/GetMDInt(4));
-      OffloadEntriesInfoManager.initializeTargetRegionEntryInfo(
-          EntryInfo, /*Order=*/GetMDInt(5));
-      break;
-    }
-    case llvm::OffloadEntriesInfoManager::OffloadEntryInfo::
-        OffloadingEntryInfoDeviceGlobalVar:
-      assert(CGM.getLangOpts().OpenMPIsDevice && "Initialization of entries is "
-                                                 "only required for the "
-                                                 "device code generation.");
-      OffloadEntriesInfoManager.initializeDeviceGlobalVarEntryInfo(
-          /*MangledName=*/GetMDString(1),
-          static_cast<
-              llvm::OffloadEntriesInfoManager::OMPTargetGlobalVarEntryKind>(
-              /*Flags=*/GetMDInt(2)),
-          /*Order=*/GetMDInt(3));
-      break;
-    }
-  }
+  OMPBuilder.loadOffloadInfoMetadata(*ME.get(), OffloadEntriesInfoManager);
 }
 
 void CGOpenMPRuntime::emitKmpRoutineEntryT(QualType KmpInt32Ty) {

llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h

@@ -1681,6 +1681,19 @@ class OpenMPIRBuilder {
                                         BasicBlock *PreInsertBefore,
                                         BasicBlock *PostInsertBefore,
                                         const Twine &Name = {});
+  /// OMP Offload Info Metadata name string
+  const std::string ompOffloadInfoName = "omp_offload.info";
+
+  /// Loads all the offload entries information from the host IR
+  /// metadata. This function is only meant to be used with device code
+  /// generation.
+  ///
+  /// \param M         Module to load Metadata info from. Module passed maybe
+  /// loaded from bitcode file, i.e, different from OpenMPIRBuilder::M module.
+  /// \param OffloadEntriesInfoManager Initialize Offload Entry information.
+  void
+  loadOffloadInfoMetadata(Module &M,
+                          OffloadEntriesInfoManager &OffloadEntriesInfoManager);
 };
 
 /// Data structure to contain the information needed to uniquely identify

llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp

@@ -4705,6 +4705,54 @@ void TargetRegionEntryInfo::getTargetRegionEntryFnName(
   getTargetRegionEntryFnName(Name, ParentName, DeviceID, FileID, Line);
 }
 
+/// Loads all the offload entries information from the host IR
+/// metadata.
+void OpenMPIRBuilder::loadOffloadInfoMetadata(
+    Module &M, OffloadEntriesInfoManager &OffloadEntriesInfoManager) {
+  // If we are in target mode, load the metadata from the host IR. This code has
+  // to match the metadata creation in createOffloadEntriesAndInfoMetadata().
+
+  NamedMDNode *MD = M.getNamedMetadata(ompOffloadInfoName);
+  if (!MD)
+    return;
+
+  for (MDNode *MN : MD->operands()) {
+    auto &&GetMDInt = [MN](unsigned Idx) {
+      auto *V = cast<ConstantAsMetadata>(MN->getOperand(Idx));
+      return cast<ConstantInt>(V->getValue())->getZExtValue();
+    };
+
+    auto &&GetMDString = [MN](unsigned Idx) {
+      auto *V = cast<MDString>(MN->getOperand(Idx));
+      return V->getString();
+    };
+
+    switch (GetMDInt(0)) {
+    default:
+      llvm_unreachable("Unexpected metadata!");
+      break;
+    case OffloadEntriesInfoManager::OffloadEntryInfo::
+        OffloadingEntryInfoTargetRegion: {
+      TargetRegionEntryInfo EntryInfo(/*ParentName=*/GetMDString(3),
+                                      /*DeviceID=*/GetMDInt(1),
+                                      /*FileID=*/GetMDInt(2),
+                                      /*Line=*/GetMDInt(4));
+      OffloadEntriesInfoManager.initializeTargetRegionEntryInfo(
+          EntryInfo, /*Order=*/GetMDInt(5));
+      break;
+    }
+    case OffloadEntriesInfoManager::OffloadEntryInfo::
+        OffloadingEntryInfoDeviceGlobalVar:
+      OffloadEntriesInfoManager.initializeDeviceGlobalVarEntryInfo(
+          /*MangledName=*/GetMDString(1),
+          static_cast<OffloadEntriesInfoManager::OMPTargetGlobalVarEntryKind>(
+              /*Flags=*/GetMDInt(2)),
+          /*Order=*/GetMDInt(3));
+      break;
+    }
+  }
+}
+
 bool OffloadEntriesInfoManager::empty() const {
   return OffloadEntriesTargetRegion.empty() &&
          OffloadEntriesDeviceGlobalVar.empty();