[flang] [llvm] [Flang][OpenMP] Generate correct present checks for implicit maps of optional allocatables (PR #138210)

[Sergio Afonso via llvm-commits]

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@@ -0,0 +1,46 @@
+!RUN: %flang_fc1 -emit-hlfir -fopenmp %s -o - | FileCheck %s
+
+module mod
+  implicit none
+contains
+  subroutine routine(a)
+    implicit none
+    real(4), allocatable, optional, intent(inout) :: a(:)
+    integer(4) :: i
+
+    !$omp target teams distribute parallel do shared(a)
+        do i=1,10
+            a(i) = i + a(i)
+        end do
+
+  end subroutine routine
+end module mod
+
+! CHECK-LABEL:   func.func @_QMmodProutine(
+! CHECK-SAME:      %[[ARG0:.*]]: !fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>> {fir.bindc_name = "a", fir.optional}) {
+! CHECK:           %[[VAL_0:.*]] = fir.alloca !fir.box<!fir.heap<!fir.array<?xf32>>>
+! CHECK:           %[[VAL_1:.*]] = fir.dummy_scope : !fir.dscope
+! CHECK:           %[[VAL_2:.*]]:2 = hlfir.declare %[[ARG0]] dummy_scope %[[VAL_1]] {fortran_attrs = #fir.var_attrs<allocatable, intent_inout, optional>, uniq_name = "_QMmodFroutineEa"} : (!fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>>, !fir.dscope) -> (!fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>>, !fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>>)
+! CHECK:           %[[VAL_8:.*]] = fir.is_present %[[VAL_2]]#1 : (!fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>>) -> i1
+! CHECK:           %[[VAL_9:.*]]:5 = fir.if %[[VAL_8]] -> (index, index, index, index, index) {
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skatrak wrote:

What are the returned values here used for?

https://github.com/llvm/llvm-project/pull/138210