[flang][debug] Support assumed size arrays.

flang/lib/Optimizer/Transforms/DebugTypeGenerator.cpp

@@ -155,28 +155,35 @@ mlir::LLVM::DITypeAttr DebugTypeGenerator::convertSequenceType(
     fir::SequenceType seqTy, mlir::LLVM::DIFileAttr fileAttr,
     mlir::LLVM::DIScopeAttr scope, mlir::Location loc) {
   mlir::MLIRContext *context = module.getContext();
-  // FIXME: Only fixed sizes arrays handled at the moment.
-  if (seqTy.hasDynamicExtents())
-    return genPlaceholderType(context);
 
   llvm::SmallVector<mlir::LLVM::DINodeAttr> elements;
   mlir::LLVM::DITypeAttr elemTy =
       convertType(seqTy.getEleTy(), fileAttr, scope, loc);
 
   for (fir::SequenceType::Extent dim : seqTy.getShape()) {
-    auto intTy = mlir::IntegerType::get(context, 64);
-    // FIXME: Only supporting lower bound of 1 at the moment. The
-    // 'SequenceType' has information about the shape but not the shift. In
-    // cases where the conversion originated during the processing of
-    // 'DeclareOp', it may be possible to pass on this information. But the
-    // type conversion should ideally be based on what information present in
-    // the type class so that it works from everywhere (e.g. when it is part
-    // of a module or a derived type.)
-    auto countAttr = mlir::IntegerAttr::get(intTy, llvm::APInt(64, dim));
-    auto lowerAttr = mlir::IntegerAttr::get(intTy, llvm::APInt(64, 1));
-    auto subrangeTy = mlir::LLVM::DISubrangeAttr::get(
-        context, countAttr, lowerAttr, nullptr, nullptr);
-    elements.push_back(subrangeTy);
+    if (dim == seqTy.getUnknownExtent()) {
+      // FIXME: This path is taken for assumed size arrays but also for arrays
+      // with non constant extent. For the latter case, the DISubrangeAttr
+      // should point to a variable which will have the extent at runtime.
+      auto subrangeTy = mlir::LLVM::DISubrangeAttr::get(
+          context, /*count=*/nullptr, /*lowerBound=*/nullptr,
+          /*upperBound*/ nullptr, /*stride*/ nullptr);
+      elements.push_back(subrangeTy);
+    } else {
+      auto intTy = mlir::IntegerType::get(context, 64);
+      // FIXME: Only supporting lower bound of 1 at the moment. The
+      // 'SequenceType' has information about the shape but not the shift. In
+      // cases where the conversion originated during the processing of
+      // 'DeclareOp', it may be possible to pass on this information. But the
+      // type conversion should ideally be based on what information present in
+      // the type class so that it works from everywhere (e.g. when it is part
+      // of a module or a derived type.)
+      auto countAttr = mlir::IntegerAttr::get(intTy, llvm::APInt(64, dim));
+      auto lowerAttr = mlir::IntegerAttr::get(intTy, llvm::APInt(64, 1));
+      auto subrangeTy = mlir::LLVM::DISubrangeAttr::get(
+          context, countAttr, lowerAttr, nullptr, nullptr);
+      elements.push_back(subrangeTy);
+    }
   }
   // Apart from arrays, the `DICompositeTypeAttr` is used for other things like
   // structure types. Many of its fields which are not applicable to arrays

flang/test/Integration/debug-assumed-size-array-2.f90

@@ -0,0 +1,22 @@
+! RUN: %flang_fc1 -emit-llvm -debug-info-kind=standalone %s -o - | FileCheck  %s
+
+XFAIL: *
+
+! Test that debug info for arrays with non constant extent is different from
+! assumed size arrays.
+
+module helper
+  implicit none
+  contains
+  subroutine fn (a1, n)
+    integer n
+    integer  a1(5, n)
+    print *, a1(1,1)
+  end subroutine fn
+end module helper
+
+! CHECK-DAG: ![[TY1:[0-9]+]] = !DICompositeType(tag: DW_TAG_array_type{{.*}}elements: ![[ELEMS1:[0-9]+]]{{.*}})
+! CHECK-DAG: ![[ELEMS1]] = !{![[ELM1:[0-9]+]], ![[ELM2:[0-9]+]]}
+! CHECK-DAG: ![[ELM1]] = !DISubrange(count: 5, lowerBound: 1)
+! CHECK-DAG: ![[ELM2]] = !DISubrange(count: [[VAR:[0-9]+]], lowerBound: 1)
+! CHECK-DAG: ![[VAR]] = !DILocalVariable

flang/test/Integration/debug-assumed-size-array.f90

@@ -0,0 +1,20 @@
+! RUN: %flang_fc1 -emit-llvm -debug-info-kind=standalone %s -o - | FileCheck  %s
+
+module helper
+  implicit none
+  contains
+  subroutine fn (a1, a2)
+	  integer  a1(5, *), a2(*)
+    print *, a1(1,1)
+    print *, a2(2)
+  end subroutine fn
+end module helper
+
+! CHECK-DAG: ![[TY1:[0-9]+]] = !DICompositeType(tag: DW_TAG_array_type{{.*}}elements: ![[ELEMS1:[0-9]+]]{{.*}})
+! CHECK-DAG: ![[ELEMS1]] = !{![[ELM1:[0-9]+]], ![[EMPTY:[0-9]+]]}
+! CHECK-DAG: ![[ELM1]] = !DISubrange(count: 5, lowerBound: 1)
+! CHECK-DAG: ![[EMPTY]] = !DISubrange()
+! CHECK-DAG: ![[TY2:[0-9]+]] = !DICompositeType(tag: DW_TAG_array_type{{.*}}elements: ![[ELEMS2:[0-9]+]]{{.*}})
+! CHECK-DAG: ![[ELEMS2]] = !{![[EMPTY:[0-9]+]]}
+! CHECK-DAG: !DILocalVariable(name: "a1"{{.*}}type: ![[TY1:[0-9]+]])
+! CHECK-DAG: !DILocalVariable(name: "a2"{{.*}}type: ![[TY2:[0-9]+]])

flang/test/Transforms/debug-assumed-size-array.fir

@@ -0,0 +1,21 @@
+// RUN: fir-opt --add-debug-info --mlir-print-debuginfo %s | FileCheck %s
+
+module attributes {dlti.dl_spec = #dlti.dl_spec<>} {
+  func.func @_QMhelperPfn(%arg0: !fir.ref<!fir.array<5x?xi32>> {fir.bindc_name = "a1"}, %arg1: !fir.ref<!fir.array<?xi32>> {fir.bindc_name = "a2"}, %arg2: !fir.ref<!fir.array<2x?xi32>> {fir.bindc_name = "a3"}) {
+    %c5 = arith.constant 5 : index
+    %c1 = arith.constant 1 : index
+    %c-1 = arith.constant -1 : index
+    %0 = fir.undefined !fir.dscope
+    %1 = fircg.ext_declare %arg0(%c5, %c-1) dummy_scope %0 {uniq_name = "_QMhelperFfnEa1"} : (!fir.ref<!fir.array<5x?xi32>>, index, index, !fir.dscope) -> !fir.ref<!fir.array<5x?xi32>> loc(#loc1)
+    %2 = fircg.ext_declare %arg1(%c-1) dummy_scope %0 {uniq_name = "_QMhelperFfnEa2"} : (!fir.ref<!fir.array<?xi32>>, index, !fir.dscope) -> !fir.ref<!fir.array<?xi32>> loc(#loc2)
+    return
+  } loc(#loc3)
+}
+#loc3 = loc("test.f90":1:1)
+#loc1 = loc("test.f90":3:1)
+#loc2 = loc("test.f90":4:1)
+
+// CHECK-DAG: #[[TY1:.*]] = #llvm.di_composite_type<tag = DW_TAG_array_type{{.*}}elements = #llvm.di_subrange<count = 5 : i64, lowerBound = 1 : i64>, #llvm.di_subrange<>>
+// CHECK-DAG: #[[TY2:.*]] = #llvm.di_composite_type<tag = DW_TAG_array_type{{.*}}elements = #llvm.di_subrange<>>
+// CHECK-DAG: #llvm.di_local_variable<{{.*}}name = "a1"{{.*}}type = #[[TY1]]>
+// CHECK-DAG: #llvm.di_local_variable<{{.*}}name = "a2"{{.*}}type = #[[TY2]]>