[llvm-branch-commits] [clang] [llvm] [mlir] [MLIR][OpenMP] Add LLVM translation support for OpenMP UserDefinedMappers (PR #124746)

[Sergio Afonso via llvm-branch-commits]

================
@@ -3529,6 +3549,84 @@ static void genMapInfos(llvm::IRBuilderBase &builder,
   }
 }
 
+static llvm::Expected<llvm::Function *>
+emitUserDefinedMapper(Operation *declMapperOp, llvm::IRBuilderBase &builder,
+                      LLVM::ModuleTranslation &moduleTranslation);
+
+static llvm::Expected<llvm::Function *>
+getOrCreateUserDefinedMapperFunc(Operation *declMapperOp,
+                                 llvm::IRBuilderBase &builder,
+                                 LLVM::ModuleTranslation &moduleTranslation) {
+  static llvm::DenseMap<const Operation *, llvm::Function *> userDefMapperMap;
+  auto iter = userDefMapperMap.find(declMapperOp);
+  if (iter != userDefMapperMap.end())
+    return iter->second;
+  llvm::Expected<llvm::Function *> mapperFunc =
+      emitUserDefinedMapper(declMapperOp, builder, moduleTranslation);
+  if (!mapperFunc)
+    return mapperFunc.takeError();
+  userDefMapperMap.try_emplace(declMapperOp, *mapperFunc);
+  return mapperFunc;
+}
+
+static llvm::Expected<llvm::Function *>
+emitUserDefinedMapper(Operation *op, llvm::IRBuilderBase &builder,
+                      LLVM::ModuleTranslation &moduleTranslation) {
+  auto declMapperOp = cast<omp::DeclareMapperOp>(op);
+  auto declMapperInfoOp =
+      *declMapperOp.getOps<omp::DeclareMapperInfoOp>().begin();
+  DataLayout dl = DataLayout(declMapperOp->getParentOfType<ModuleOp>());
+  llvm::OpenMPIRBuilder *ompBuilder = moduleTranslation.getOpenMPBuilder();
+  llvm::Type *varType = moduleTranslation.convertType(declMapperOp.getType());
+  std::string mapperName = ompBuilder->createPlatformSpecificName(
+      {"omp_mapper", declMapperOp.getSymName()});
+  SmallVector<Value> mapVars = declMapperInfoOp.getMapVars();
+
+  using InsertPointTy = llvm::OpenMPIRBuilder::InsertPointTy;
+
+  // Fill up the arrays with all the mapped variables.
+  MapInfosTy combinedInfo;
+  auto genMapInfoCB =
+      [&](InsertPointTy codeGenIP, llvm::Value *ptrPHI,
+          llvm::Value *unused2) -> llvm::OpenMPIRBuilder::MapInfosOrErrorTy {
+    builder.restoreIP(codeGenIP);
+    moduleTranslation.mapValue(declMapperOp.getRegion().getArgument(0), ptrPHI);
----------------
skatrak wrote:

Nit: It would probably be good to add to the PR where you're introducing `DeclareMapperOp`, an `extraClassDeclaration` and simplify this like it's done for other similar operations:
```suggestion
    moduleTranslation.mapValue(declMapperOp.getMoldArg(), ptrPHI);
```

https://github.com/llvm/llvm-project/pull/124746