LibDebug: Make use of the newly supported data forms

With this change, our DWARF 5 support is nearly feature-complete.

Userland/Libraries/LibDebug/Dwarf/AddressRanges.cpp

@@ -31,6 +31,12 @@ void AddressRanges::for_each_range(Function<void(Range)> callback)
             current_base_address = base;
             break;
         }
+        case RangeListEntryType::BaseAddressX: {
+            FlatPtr index;
+            m_range_lists_stream.read_LEB128_unsigned(index);
+            current_base_address = m_compilation_unit.get_address(index);
+            break;
+        }
         case RangeListEntryType::OffsetPair: {
             Optional<FlatPtr> base_address = current_base_address;
             if (!base_address.has_value()) {
@@ -56,6 +62,21 @@ void AddressRanges::for_each_range(Function<void(Range)> callback)
             callback(Range { start, start + length });
             break;
         }
+        case RangeListEntryType::StartXEndX: {
+            size_t start, end;
+            m_range_lists_stream.read_LEB128_unsigned(start);
+            m_range_lists_stream.read_LEB128_unsigned(end);
+            callback(Range { m_compilation_unit.get_address(start), m_compilation_unit.get_address(end) });
+            break;
+        }
+        case RangeListEntryType::StartXLength: {
+            size_t start, length;
+            m_range_lists_stream.read_LEB128_unsigned(start);
+            m_range_lists_stream.read_LEB128_unsigned(length);
+            auto start_addr = m_compilation_unit.get_address(start);
+            callback(Range { start_addr, start_addr + length });
+            break;
+        }
         case RangeListEntryType::EndOfList:
             return;
         default:

Userland/Libraries/LibDebug/Dwarf/DwarfInfo.cpp

@@ -326,10 +326,16 @@ void DwarfInfo::build_cached_dies() const
     auto get_ranges_of_die = [this](DIE const& die) -> Vector<DIERange> {
         auto ranges = die.get_attribute(Attribute::Ranges);
         if (ranges.has_value()) {
-            // TODO Support DW_FORM_rnglistx
-            if (ranges->form() != AttributeDataForm::SecOffset)
-                return {};
-            auto offset = ranges->as_unsigned();
+            size_t offset;
+            if (ranges->form() == AttributeDataForm::SecOffset) {
+                offset = ranges->as_unsigned();
+            } else {
+                auto index = ranges->as_unsigned();
+                auto base = die.compilation_unit().range_lists_base();
+                // FIXME: This assumes that the format is DWARf32
+                auto offsets = reinterpret_cast<u32 const*>(debug_range_lists_data().offset(base));
+                offset = offsets[index] + base;
+            }
             AddressRanges address_ranges(debug_range_lists_data(), offset, die.compilation_unit());
             Vector<DIERange> entries;
             address_ranges.for_each_range([&entries](auto range) {