[flang] Accept polymorphic component element in storage_size

[clementval]

Summary

When an element is extracted from a polymorphic array, it is
represented as a PolymorphicValue. The PolymorphicValue is
not a boxed value but holds the original polyrmophic array
and the element itself. This was raising an error in storage_size
lowering since we expect a boxed value to take advantage of
fir.box_elesize.
This patch handles PolymorphicValue correctly.

[PeteSteinfeld]

All builds and tests correctly and looks good.

flang/lib/Optimizer/Builder/IntrinsicCall.cpp

if (!absentKind) {
     mlir::Operation *defKind = fir::getBase(args[1]).getDefiningOp();
     assert(mlir::isa<mlir::arith::ConstantOp>(*defKind) &&
            "kind not a constant");
     auto constOp = mlir::dyn_cast<mlir::arith::ConstantOp>(*defKind);
     kindTy = builder.getIntegerType(
         builder.getKindMap().getIntegerBitsize(fir::toInt(constOp)));
   }
 
-  if (box.getType().isa<fir::ReferenceType>())
+  if (args[0].getBoxOf<fir::PolymorphicValue>()) {
+    box = builder.createBox(loc, args[0], /*isPolymorphic=*/true);
+  } else if (box.getType().isa<fir::ReferenceType>()) {
     box = builder.create<fir::LoadOp>(loc, box);
+  }
   mlir::Value eleSize = builder.create<fir::BoxEleSizeOp>(loc, kindTy, box);
   mlir::Value c8 = builder.createIntegerConstant(loc, kindTy, 8);
   return builder.create<mlir::arith::MulIOp>(loc, eleSize, c8);
 }
 
 // SUM
 fir::ExtendedValue
 IntrinsicLibrary::genSum(mlir::Type resultType,

flang/test/Lower/Intrinsics/storage_size.f90

 ! RUN: bbc -emit-fir -polymorphic-type %s -o - | FileCheck %s
 
 module storage_size_test
   type :: p1
     integer :: a
   end type
 
   type, extends(p1) :: p2
     integer :: b
   end type
 
+  type :: p3
+    class(p1), pointer :: p(:)
+  end type
+
 contains
 
   integer function unlimited_polymorphic_pointer(p) result(size)
     class(*), pointer :: p
     size = storage_size(p)
   end function
 
 ! CHECK-LABEL: func.func @_QMstorage_size_testPunlimited_polymorphic_pointer(

 ! CHECK: %[[SIZE:.*]] = fir.alloca i64 {bindc_name = "size", uniq_name = "_QMstorage_size_testFpolymorphic_rankEsize"}
 ! CHECK: %[[ELE_SIZE:.*]] = fir.box_elesize %[[P]] : (!fir.class<!fir.type<_QMstorage_size_testTp1{a:i32}>>) -> i64
 ! CHECK: %[[C8:.*]] = arith.constant 8 : i64
 ! CHECK: %[[BITS:.*]] = arith.muli %[[ELE_SIZE]], %[[C8]] : i64
 ! CHECK: fir.store %[[BITS]] to %[[SIZE]] : !fir.ref<i64>
 ! CHECK: %[[RES:.*]] = fir.load %[[SIZE]] : !fir.ref<i64>
 ! CHECK: return %[[RES]] : i64
 
+  integer function polymorphic_value(t) result(size)
+    type(p3) :: t
+    size = storage_size(t%p(1))
+  end function
+
+! CHECK-LABEL: func.func @_QMstorage_size_testPpolymorphic_value(
+! CHECK-SAME: %[[T:.*]]: !fir.ref<!fir.type<_QMstorage_size_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>}>> {fir.bindc_name = "t"}) -> i32 {
+! CHECK: %[[ALLOCA:.*]] = fir.alloca i32 {bindc_name = "size", uniq_name = "_QMstorage_size_testFpolymorphic_valueEsize"}
+! CHECK: %[[FIELD_P:.*]] = fir.field_index p, !fir.type<_QMstorage_size_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>}>
+! CHECK: %[[COORD_P:.*]] = fir.coordinate_of %[[T]], %[[FIELD_P]] : (!fir.ref<!fir.type<_QMstorage_size_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>}>>, !fir.field) -> !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>>
+! CHECK: %[[LOAD_COORD_P:.*]] = fir.load %[[COORD_P]] : !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>>
+! CHECK: %[[C0:.*]] = arith.constant 0 : index
+! CHECK: %[[BOX_DIMS:.*]]:3 = fir.box_dims %[[LOAD_COORD_P]], %[[C0]] : (!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>, index) -> (index, index, index)
+! CHECK: %[[C1:.*]] = arith.constant 1 : i64
+! CHECK: %[[DIMI64:.*]] = fir.convert %[[BOX_DIMS]]#0 : (index) -> i64
+! CHECK: %[[IDX:.*]] = arith.subi %[[C1]], %[[DIMI64]] : i64
+! CHECK: %[[COORD_OF:.*]] = fir.coordinate_of %[[LOAD_COORD_P]], %[[IDX]] : (!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>, i64) -> !fir.ref<!fir.type<_QMstorage_size_testTp1{a:i32}>>
+! CHECK: %[[BOXED:.*]] = fir.embox %[[COORD_OF]] source_box %[[LOAD_COORD_P]] : (!fir.ref<!fir.type<_QMstorage_size_testTp1{a:i32}>>, !fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMstorage_size_testTp1{a:i32}>>>>) -> !fir.class<!fir.type<_QMstorage_size_testTp1{a:i32}>>
+! CHECK: %[[ELE_SIZE:.*]] = fir.box_elesize %[[BOXED]] : (!fir.class<!fir.type<_QMstorage_size_testTp1{a:i32}>>) -> i32
+! CHECK: %[[C8:.*]] = arith.constant 8 : i32
+! CHECK: %[[SIZE:.*]] = arith.muli %[[ELE_SIZE]], %[[C8]] : i32
+! CHECK: fir.store %[[SIZE]] to %[[ALLOCA]] : !fir.ref<i32>
+! CHECK: %[[RET:.*]] = fir.load %[[ALLOCA]] : !fir.ref<i32>
+! CHECK: return %[[RET]] : i32
+
 end module