[flang-commits] [flang] [flang][pft] visit original symbol in acc use_device (PR #194588)

[Eugene Epshteyn via flang-commits]

================
@@ -2221,6 +2221,25 @@ struct SymbolVisitor {
     return false;
   }
 
+  bool Pre(const Fortran::parser::AccClause::UseDevice &useDevice) {
+    // For use_device, each symbol's parser Name has been given a local copy
+    // of the symbol with the DEVICE attribute. The original symbol will be
+    // needed in lowering and may not appear in the parse tree of the function
+    // anymore. Visit it now: it is not directly accessible from the construct
+    // symbol, so the parent scope must be searched to find it.
+    for (const auto &accObject : useDevice.v.v) {
+      if (const semantics::Symbol *deviceSym =
+              Fortran::parser::GetFirstName(accObject).symbol) {
+        if (const semantics::Symbol *hostSym =
+                deviceSym->owner().parent().FindSymbol(deviceSym->name()))
----------------
eugeneepshteyn wrote:

Question:
```
module m
  real :: a(100)
contains
  subroutine s
    block
      integer :: a(50)        ! shadows module a in this block
      !$acc host_data use_device(a)   ! must instantiate the right 'a'
      !$acc end host_data
    end block
  end subroutine
end module
```
Will this get to the correct `a`? I assume it should find `integer :: a(50)`.

https://github.com/llvm/llvm-project/pull/194588