[flang-commits] [flang] [flang][OpenMP] Extend `do concurrent` mapping to device (PR #155987)

[Pranav Bhandarkar via flang-commits]

================
@@ -439,6 +572,244 @@ class DoConcurrentConversion
     return loopNestOp;
   }
 
+  void genBoundsOps(fir::FirOpBuilder &builder, mlir::Value liveIn,
+                    mlir::Value rawAddr,
+                    llvm::SmallVectorImpl<mlir::Value> &boundsOps) const {
+    fir::ExtendedValue extVal =
+        hlfir::translateToExtendedValue(rawAddr.getLoc(), builder,
+                                        hlfir::Entity{liveIn},
+                                        /*contiguousHint=*/
+                                        true)
+            .first;
+    fir::factory::AddrAndBoundsInfo info = fir::factory::getDataOperandBaseAddr(
+        builder, rawAddr, /*isOptional=*/false, rawAddr.getLoc());
+    boundsOps = fir::factory::genImplicitBoundsOps<mlir::omp::MapBoundsOp,
+                                                   mlir::omp::MapBoundsType>(
+        builder, info, extVal,
+        /*dataExvIsAssumedSize=*/false, rawAddr.getLoc());
+  }
+
+  mlir::omp::MapInfoOp genMapInfoOpForLiveIn(fir::FirOpBuilder &builder,
+                                             mlir::Value liveIn) const {
+    mlir::Value rawAddr = liveIn;
+    llvm::StringRef name;
+
+    mlir::Operation *liveInDefiningOp = liveIn.getDefiningOp();
+    auto declareOp =
+        mlir::dyn_cast_if_present<hlfir::DeclareOp>(liveInDefiningOp);
+
+    if (declareOp != nullptr) {
+      // Use the raw address to avoid unboxing `fir.box` values whenever
+      // possible. Put differently, if we have access to the direct value memory
+      // reference/address, we use it.
+      rawAddr = declareOp.getOriginalBase();
+      name = declareOp.getUniqName();
+    }
+
+    if (!llvm::isa<mlir::omp::PointerLikeType>(rawAddr.getType())) {
+      mlir::OpBuilder::InsertionGuard guard(builder);
+      builder.setInsertionPointAfter(liveInDefiningOp);
+      auto copyVal = builder.createTemporary(liveIn.getLoc(), liveIn.getType());
+      builder.createStoreWithConvert(copyVal.getLoc(), liveIn, copyVal);
+      rawAddr = copyVal;
+    }
+
+    mlir::Type liveInType = liveIn.getType();
+    mlir::Type eleType = liveInType;
+    if (auto refType = mlir::dyn_cast<fir::ReferenceType>(liveInType))
+      eleType = refType.getElementType();
+
+    llvm::omp::OpenMPOffloadMappingFlags mapFlag =
+        llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_IMPLICIT;
+    mlir::omp::VariableCaptureKind captureKind =
+        mlir::omp::VariableCaptureKind::ByRef;
+
+    if (fir::isa_trivial(eleType) || fir::isa_char(eleType)) {
----------------
bhandarkar-pranav wrote:

There is a corner case here that'll need to be checked. If the size of `eleType` is > pointer type size for the device, then we cannot pass by copy. It involves using `DataLayout`. See [canPassByValue here](https://github.com/bhandarkar-pranav/llvm-project/blob/main/flang/lib/Optimizer/OpenMP/MapsForPrivatizedSymbols.cpp#L61)

https://github.com/llvm/llvm-project/pull/155987