[flang] Recognize unused dummy arguments during lowering with HLFIR.

So far we've relied on AllocaOp to represent the dummy arguments
not declared for the current entry. With HLFIR we have to account
for hlfir::DeclareOp.

Differential Revision: https://reviews.llvm.org/D149231

diff --git a/flang/lib/Lower/ConvertVariable.cpp b/flang/lib/Lower/ConvertVariable.cpp
index 4d0375b..451f1e2 100644 (file)
--- a/flang/lib/Lower/ConvertVariable.cpp
+++ b/flang/lib/Lower/ConvertVariable.cpp
@@ -721,9 +721,12 @@ static void deallocateIntentOut(Fortran::lower::AbstractConverter &converter,
     if (auto mutBox = extVal.getBoxOf<fir::MutableBoxValue>()) {
       // The dummy argument is not passed in the ENTRY so it should not be
       // deallocated.
-      if (mlir::Operation *op = mutBox->getAddr().getDefiningOp())
-        if (mlir::isa<fir::AllocaOp>(op))
+      if (mlir::Operation *op = mutBox->getAddr().getDefiningOp()) {
+        if (auto declOp = mlir::dyn_cast<hlfir::DeclareOp>(op))
+          op = declOp.getMemref().getDefiningOp();
+        if (op && mlir::isa<fir::AllocaOp>(op))
           return;
+      }
       mlir::Location loc = converter.getCurrentLocation();
       fir::FirOpBuilder &builder = converter.getFirOpBuilder();
       auto genDeallocateWithTypeDesc = [&]() {

diff --git a/flang/test/HLFIR/dummy_deallocation.f90 b/flang/test/HLFIR/dummy_deallocation.f90
new file mode 100644 (file)
index 0000000..9d3c51c
--- /dev/null
+++ b/flang/test/HLFIR/dummy_deallocation.f90
@@ -0,0 +1,16 @@
+! RUN: bbc -emit-fir -hlfir %s -o - | FileCheck %s
+! RUN: bbc -emit-fir %s -o - | FileCheck %s
+
+! Test that the intent(out) allocatable dummy argument
+! is not deallocated in entry SUB_B.
+
+! CHECK-LABEL: func.func @_QPsub_a
+! CHECK: fir.freemem
+
+! CHECK-LABEL: func.func @_QPsub_b
+! CHECK-NOT: fir.freemem
+SUBROUTINE SUB_A(A)
+  INTEGER, INTENT(out), ALLOCATABLE, DIMENSION (:) :: A
+  RETURN
+  ENTRY SUB_B
+END SUBROUTINE SUB_A