[flang] lower assumed-rank inquiries - part 1 (#94475)

Lower assumed-rank inquiries, except SIZE/SHAPE/UBOUND/LBOUND. This is
mainly about adding tests, and removing a couple TODOs in helpers.

Author: jeanPerier

flang/lib/Optimizer/Builder/IntrinsicCall.cpp

@@ -4965,10 +4965,6 @@ fir::ExtendedValue
 IntrinsicLibrary::genIsContiguous(mlir::Type resultType,
                                   llvm::ArrayRef<fir::ExtendedValue> args) {
   assert(args.size() == 1);
-  if (const auto *boxValue = args[0].getBoxOf<fir::BoxValue>())
-    if (boxValue->hasAssumedRank())
-      TODO(loc, "intrinsic: is_contiguous with assumed rank argument");
-
   return builder.createConvert(
       loc, resultType,
       fir::runtime::genIsContiguous(builder, loc, fir::getBase(args[0])));

flang/lib/Optimizer/Builder/MutableBox.cpp

@@ -394,6 +394,8 @@ static bool readToBoxValue(const fir::MutableBoxValue &box,
   // Track value as fir.box
   if ((box.isDerived() && mayBePolymorphic) || box.isUnlimitedPolymorphic())
     return true;
+  if (box.hasAssumedRank())
+    return true;
   // Intrinsic allocatables are contiguous, no need to track the value by
   // fir.box.
   if (box.isAllocatable() || box.rank() == 0)
@@ -409,14 +411,12 @@ fir::factory::genMutableBoxRead(fir::FirOpBuilder &builder, mlir::Location loc,
                                 const fir::MutableBoxValue &box,
                                 bool mayBePolymorphic,
                                 bool preserveLowerBounds) {
-  if (box.hasAssumedRank())
-    TODO(loc, "assumed rank allocatables or pointers");
   llvm::SmallVector<mlir::Value> lbounds;
   llvm::SmallVector<mlir::Value> extents;
   llvm::SmallVector<mlir::Value> lengths;
   if (readToBoxValue(box, mayBePolymorphic)) {
     auto reader = MutablePropertyReader(builder, loc, box);
-    if (preserveLowerBounds)
+    if (preserveLowerBounds && !box.hasAssumedRank())
       reader.getLowerBounds(lbounds);
     return fir::BoxValue{reader.getIrBox(), lbounds,
                          box.nonDeferredLenParams()};