[flang] [llvm] [flang] implement show_descriptor intrinsic, a non-standard extension (PR #169137)

[via llvm-commits]

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@@ -0,0 +1,237 @@
+! RUN: bbc -emit-fir %s -o - | FileCheck %s
+
+subroutine test_int
+! CHECK-LABEL:   func.func @_QPtest_int() {
+  implicit none
+  integer :: n
+  integer,allocatable :: a(:)
+  n = 5
+  allocate(a(n))
+! CHECK:           %[[C3:.*]] = arith.constant 3 : index
+! CHECK:           %[[C1:.*]] = arith.constant 1 : index
+! CHECK:           %[[C5:.*]] = arith.constant 5 : i32
+! CHECK:           %[[C0:.*]] = arith.constant 0 : index
+! CHECK:           %[[DUMMY_SCOPE_0:.*]] = fir.dummy_scope : !fir.dscope
+! CHECK:           %[[ALLOCA_0:.*]] = fir.alloca !fir.box<!fir.heap<!fir.array<?xi32>>> {bindc_name = "a", uniq_name = "_QFtest_intEa"}
+! CHECK:           %[[ZERO_BITS_0:.*]] = fir.zero_bits !fir.heap<!fir.array<?xi32>>
+! CHECK:           %[[SHAPE_0:.*]] = fir.shape %[[C0]] : (index) -> !fir.shape<1>
+! CHECK:           %[[EMBOX_0:.*]] = fir.embox %[[ZERO_BITS_0]](%[[SHAPE_0]]) : (!fir.heap<!fir.array<?xi32>>, !fir.shape<1>) -> !fir.box<!fir.heap<!fir.array<?xi32>>>
+! CHECK:           fir.store %[[EMBOX_0]] to %[[ALLOCA_0]] : !fir.ref<!fir.box<!fir.heap<!fir.array<?xi32>>>>
+! CHECK:           %[[DECLARE_0:.*]] = fir.declare %[[ALLOCA_0]] {fortran_attrs = #fir.var_attrs<allocatable>, uniq_name = "_QFtest_intEa"} : (!fir.ref<!fir.box<!fir.heap<!fir.array<?xi32>>>>) -> !fir.ref<!fir.box<!fir.heap<!fir.array<?xi32>>>>
+! CHECK:           %[[ALLOCA_1:.*]] = fir.alloca i32 {bindc_name = "n", uniq_name = "_QFtest_intEn"}
+! CHECK:           %[[DECLARE_1:.*]] = fir.declare %[[ALLOCA_1]] {uniq_name = "_QFtest_intEn"} : (!fir.ref<i32>) -> !fir.ref<i32>
+! CHECK:           fir.store %[[C5]] to %[[DECLARE_1]] : !fir.ref<i32>
+! CHECK:           %[[LOAD_0:.*]] = fir.load %[[DECLARE_1]] : !fir.ref<i32>
+! CHECK:           %[[CONVERT_0:.*]] = fir.convert %[[LOAD_0]] : (i32) -> index
+! CHECK:           %[[CMPI_0:.*]] = arith.cmpi sgt, %[[CONVERT_0]], %[[C0]] : index
+! CHECK:           %[[SELECT_0:.*]] = arith.select %[[CMPI_0]], %[[CONVERT_0]], %[[C0]] : index
+! CHECK:           %[[ALLOCMEM_0:.*]] = fir.allocmem !fir.array<?xi32>, %[[SELECT_0]] {fir.must_be_heap = true, uniq_name = "_QFtest_intEa.alloc"}
+
+  call __builtin_show_descriptor(a)
+! CHECK:           %[[SHAPE_1:.*]] = fir.shape %[[SELECT_0]] : (index) -> !fir.shape<1>
+! CHECK:           %[[EMBOX_1:.*]] = fir.embox %[[ALLOCMEM_0]](%[[SHAPE_1]]) : (!fir.heap<!fir.array<?xi32>>, !fir.shape<1>) -> !fir.box<!fir.heap<!fir.array<?xi32>>>
+! CHECK:           fir.store %[[EMBOX_1]] to %[[DECLARE_0]] : !fir.ref<!fir.box<!fir.heap<!fir.array<?xi32>>>>
+! CHECK:           %[[LOAD_1:.*]] = fir.load %[[DECLARE_0]] : !fir.ref<!fir.box<!fir.heap<!fir.array<?xi32>>>>
+! CHECK:           fir.call @_FortranAShowDescriptor(%[[LOAD_1]]) fastmath<contract> : (!fir.box<!fir.heap<!fir.array<?xi32>>>) -> ()
+
+  call __builtin_show_descriptor(a(1:3))
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jeanPerier wrote:

Can you update the test to do use flang_debug and use show_descriptor?

User should not use the flang __builtin directly, and it would be good if the test also exercise the new module (I think  bcc should pick the intrinsic modules, if it does not you can update the test to use flang_fc1). 

https://github.com/llvm/llvm-project/pull/169137