Fixing the location attribute added to mapInfoOp

Named location attribute added tgt_info shall be used by runtime calls
like ompx_dump_mapping_tables to print the information of variables that
are mapped to the device. Before this change, ompx_dump_mapping_tables
was printing the wrong location information.

Author: anchuraj

flang/lib/Lower/OpenMP/ClauseProcessor.cpp

@@ -903,9 +903,13 @@ bool ClauseProcessor::processMap(
           // Explicit map captures are captured ByRef by default,
           // optimisation passes may alter this to ByCopy or other capture
           // types to optimise
+          auto context = converter.getFirOpBuilder().getContext();
+          auto location = mlir::NameLoc::get(
+              mlir::StringAttr::get(context, asFortran.str()),
+              symAddr.getLoc());
           mlir::Value mapOp = createMapInfoOp(
-              firOpBuilder, clauseLocation, symAddr, mlir::Value{},
-              asFortran.str(), bounds, {},
+              firOpBuilder, location, symAddr, mlir::Value{}, asFortran.str(),
+              bounds, {},
               static_cast<
                   std::underlying_type_t<llvm::omp::OpenMPOffloadMappingFlags>>(
                   mapTypeBits),

flang/lib/Lower/OpenMP/OpenMP.cpp

@@ -1644,11 +1644,14 @@ genTargetOp(Fortran::lower::AbstractConverter &converter,
         } else if (!fir::isa_builtin_cptr_type(eleType)) {
           mapFlag |= llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_TO;
           mapFlag |= llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_FROM;
-        }
-
+        };
+        auto context = converter.getFirOpBuilder().getContext();
+        auto location = mlir::NameLoc::get(
+            mlir::StringAttr::get(context, sym.name().ToString()),
+            baseOp.getLoc());
         mlir::Value mapOp = createMapInfoOp(
-            firOpBuilder, baseOp.getLoc(), baseOp, mlir::Value{}, name.str(),
-            bounds, {},
+            firOpBuilder, location, baseOp, mlir::Value{}, name.str(), bounds,
+            {},
             static_cast<
                 std::underlying_type_t<llvm::omp::OpenMPOffloadMappingFlags>>(
                 mapFlag),

offload/test/offloading/fortran/dump_map_tables.f90

@@ -0,0 +1,38 @@
+! Offloading test with a target region mapping a declare target
+! Fortran array writing some values to it and checking the host
+! correctly receives the updates made on the device.
+! REQUIRES: flang
+! UNSUPPORTED: nvptx64-nvidia-cuda-LTO
+! UNSUPPORTED: aarch64-unknown-linux-gnu
+! UNSUPPORTED: aarch64-unknown-linux-gnu-LTO
+! UNSUPPORTED: x86_64-pc-linux-gnu
+! UNSUPPORTED: x86_64-pc-linux-gnu-LTO
+
+! RUN: %libomptarget-compile-fortran-run-and-check-generic
+
+program map_dump_example
+  INTERFACE
+    SUBROUTINE ompx_dump_mapping_tables() BIND(C)
+    END SUBROUTINE ompx_dump_mapping_tables
+  END INTERFACE
+
+  integer i,j,k,N
+  integer async_q(4)
+  real :: A(5000000),B(5000000),C(5000000)
+  N=5000000
+  do i=1, N
+    A(i)=0
+  enddo
+! clang-format off
+! CHECK: omptarget device 0 info: OpenMP Host-Device pointer mappings after block
+! CHECK-NEXT: omptarget device 0 info: Host Ptr Target Ptr Size (B) DynRefCount HoldRefCount Declaration
+! CHECK-NEXT: omptarget device 0 info: {{(0x[0-9a-f]{16})}} {{(0x[0-9a-f]{16})}}  20000000 1 0 {{.*}} at a(:n):21:11
+! clang-format on
+!$omp target enter data map(to:A(:N))
+  call ompx_dump_mapping_tables()
+!$omp target parallel do
+  do i=1, N
+    A(i)=B(i)*C(i)
+  enddo
+!$omp target exit data map(from:A)
+end program