[flang-commits] [flang] Get the BoxType from the RHS instead of LHS for polymorphic pointer assignment inside FORALL. (PR #164279)

[via flang-commits]

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@@ -0,0 +1,45 @@
+! Test lower of elemental user defined assignments
+! RUN: bbc -emit-fir %s -o - | FileCheck %s
+
+! CHECK-LABEL: c.func @_QPforallpolymorphic
+  subroutine forallPolymorphic()
+  TYPE :: DT
+    CLASS(DT), POINTER    :: Ptr(:) => NULL()
+  END TYPE
+
+  TYPE, EXTENDS(DT) :: DT1
+  END TYPE
+
+  TYPE(DT1), TARGET  :: Tar1(10)
+  CLASS(DT), POINTER :: T(:)
+  integer :: I
+
+  FORALL (I=1:10)
+    T(I)%Ptr => Tar1
+  END FORALL
+
+! CHECK: %[[V_11:[0-9]+]] = fir.alloca !fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>> {bindc_name = "t", uniq_name = "_QFforallpolymorphicEt"}
+! CHECK: %[[V_15:[0-9]+]] = fir.declare %[[V_11]] {fortran_attrs = #fir.var_attrs<pointer>, uniq_name = "_QFforallpolymorphicEt"} : (!fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>>) -> !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>>
+! CHECK: %[[V_16:[0-9]+]] = fir.alloca !fir.array<10x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>> {bindc_name = "tar1", fir.target, uniq_name = "_QFforallpolymorphicEtar1"}
+! CHECK: %[[V_17:[0-9]+]] = fir.shape %c10 : (index) -> !fir.shape<1>
+! CHECK: %[[V_18:[0-9]+]] = fir.declare %[[V_16]](%[[V_17]]) {fortran_attrs = #fir.var_attrs<target>, uniq_name = "_QFforallpolymorphicEtar1"} : (!fir.ref<!fir.array<10x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>>>, !fir.shape<1>) -> !fir.ref<!fir.array<10x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>>>
+! CHECK: %[[V_19:[0-9]+]] = fir.embox %[[V_18]](%[[V_17]]) : (!fir.ref<!fir.array<10x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>>>, !fir.shape<1>) -> !fir.box<!fir.array<10x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>>>
+! CHECK: %[[V_34:[0-9]+]] = fir.convert %c1_i32 : (i32) -> index
+! CHECK: %[[V_35:[0-9]+]] = fir.convert %c10_i32 : (i32) -> index
+! CHECK: fir.do_loop %arg0 = %[[V_34]] to %[[V_35]] step %c1
+! CHECK: {
+! CHECK: %[[V_36:[0-9]+]] = fir.convert %arg0 : (index) -> i32
+! CHECK: %[[V_37:[0-9]+]] = fir.load %[[V_15]] : !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>>
+! CHECK: %[[V_38:[0-9]+]] = fir.convert %[[V_36]] : (i32) -> i64
+! CHECK: %[[C0:.*]] = arith.constant 0 : index
+! CHECK: %[[V_39:[0-9]+]]:3 = fir.box_dims %37, %[[C0]] : (!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>, index) -> (index, index, index)
+! CHECK: %[[V_40:[0-9]+]] = fir.shift %[[V_39]]#0 : (index) -> !fir.shift<1>
+! CHECK: %[[V_41:[0-9]+]] = fir.array_coor %[[V_37]](%[[V_40]]) %[[V_38]] : (!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>, !fir.shift<1>, i64) -> !fir.ref<!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>
+! CHECK: %[[V_42:[0-9]+]] = fir.embox %[[V_41]] source_box %[[V_37]] : (!fir.ref<!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>, !fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>) -> !fir.class<!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>
+! CHECK: %[[V_43:[0-9]+]] = fir.field_index ptr, !fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>
+! CHECK: %[[V_44:[0-9]+]] = fir.coordinate_of %[[V_42]], ptr : (!fir.class<!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>) -> !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>>
+! CHECK: %[[V_45:[0-9]+]] = fir.rebox %[[V_19]] : (!fir.box<!fir.array<10x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>>>) -> !fir.box<!fir.array<?x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>>>
+! CHECK: %[[V_46:[0-9]+]] = fir.convert %[[V_45]] : (!fir.box<!fir.array<?x!fir.type<_QFforallpolymorphicTdt1{dt:!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>}>>>) -> !fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>
+! CHECK: fir.store %[[V_46]] to %[[V_44]] : !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt{ptr:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFforallpolymorphicTdt>>>>}>>>>>
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jeanPerier wrote:

This will end-up erasing the pointer attribute in the runtime descriptor for the pointers because it was not set in the descriptor value that `V_45`, and convert is a reinterpret_cast for descriptor (it does not change/ensure that the runtime attributes match the type attributes).
Suggestion fix in code.

https://github.com/llvm/llvm-project/pull/164279