Index: lldb/unittests/Process/Utility/CMakeLists.txt
===================================================================
--- lldb/unittests/Process/Utility/CMakeLists.txt
+++ lldb/unittests/Process/Utility/CMakeLists.txt
@@ -15,9 +15,10 @@
   ${NETBSD_SOURCES})
 
 add_lldb_unittest(ProcessUtilityTests
-  RegisterContextTest.cpp
+  DynamicRegisterInfoTest.cpp
   LinuxProcMapsTest.cpp
   MemoryTagManagerAArch64MTETest.cpp
+  RegisterContextTest.cpp
   ${PLATFORM_SOURCES}
 
   LINK_LIBS
Index: lldb/unittests/Process/Utility/DynamicRegisterInfoTest.cpp
===================================================================
--- /dev/null
+++ lldb/unittests/Process/Utility/DynamicRegisterInfoTest.cpp
@@ -0,0 +1,98 @@
+//===-- DynamicRegisterInfoTest.cpp ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+#include "Plugins/Process/Utility/DynamicRegisterInfo.h"
+
+#include "lldb/Utility/ArchSpec.h"
+
+using namespace lldb_private;
+
+static uint32_t AddRegister(DynamicRegisterInfo &info, const char *name,
+                            uint32_t byte_size,
+                            std::vector<uint32_t> value_regs = {},
+                            std::vector<uint32_t> invalidate_regs = {}) {
+  ConstString group{"group"};
+  static uint32_t regnum = 0;
+
+  struct RegisterInfo new_reg {
+    name, nullptr, byte_size, LLDB_INVALID_INDEX32, lldb::eEncodingUint,
+        lldb::eFormatUnsigned,
+        {LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, regnum,
+         regnum},
+        nullptr, nullptr, nullptr, 0
+  };
+
+  if (!value_regs.empty()) {
+    value_regs.push_back(LLDB_INVALID_REGNUM);
+    new_reg.value_regs = value_regs.data();
+  }
+  if (!invalidate_regs.empty()) {
+    invalidate_regs.push_back(LLDB_INVALID_REGNUM);
+    new_reg.invalidate_regs = invalidate_regs.data();
+  }
+
+  info.AddRegister(new_reg, group);
+  return regnum++;
+}
+
+TEST(DynamicRegisterInfoTest, finalize_regs) {
+  DynamicRegisterInfo info;
+
+  // Add regular registers
+  uint32_t b1 = AddRegister(info, "b1", 8);
+  uint32_t b2 = AddRegister(info, "b2", 8);
+
+  // Add a few sub-registers
+  uint32_t s1 = AddRegister(info, "s1", 4, {b1});
+  uint32_t s2 = AddRegister(info, "s2", 4, {b2});
+
+  // Add a register with invalidate_regs
+  uint32_t i1 = AddRegister(info, "i1", 8, {}, {b1});
+
+  // Add a register with indirect invalidate regs to be expanded
+  // TODO: why is it done conditionally to value_regs?
+  uint32_t i2 = AddRegister(info, "i2", 4, {b2}, {i1});
+
+  info.Finalize(lldb_private::ArchSpec());
+
+  const RegisterInfo *added_reg = info.GetRegisterInfoAtIndex(0);
+  ASSERT_NE(added_reg, nullptr);
+  EXPECT_EQ(added_reg->byte_offset, 0U);
+
+  added_reg = info.GetRegisterInfoAtIndex(1);
+  ASSERT_NE(added_reg, nullptr);
+  EXPECT_EQ(added_reg->byte_offset, 8U);
+
+  added_reg = info.GetRegisterInfoAtIndex(2);
+  ASSERT_NE(added_reg, nullptr);
+  EXPECT_EQ(added_reg->byte_offset, 0U);
+  EXPECT_EQ(added_reg->value_regs[0], b1);
+  EXPECT_EQ(added_reg->value_regs[1], LLDB_INVALID_REGNUM);
+
+  added_reg = info.GetRegisterInfoAtIndex(3);
+  ASSERT_NE(added_reg, nullptr);
+  EXPECT_EQ(added_reg->byte_offset, 8U);
+  EXPECT_EQ(added_reg->value_regs[0], b2);
+  EXPECT_EQ(added_reg->value_regs[1], LLDB_INVALID_REGNUM);
+
+  added_reg = info.GetRegisterInfoAtIndex(4);
+  ASSERT_NE(added_reg, nullptr);
+  EXPECT_EQ(added_reg->byte_offset, 16U);
+  EXPECT_EQ(added_reg->invalidate_regs[0], b1);
+  EXPECT_EQ(added_reg->invalidate_regs[1], LLDB_INVALID_REGNUM);
+
+  added_reg = info.GetRegisterInfoAtIndex(5);
+  ASSERT_NE(added_reg, nullptr);
+  EXPECT_EQ(added_reg->byte_offset, 8U);
+  EXPECT_EQ(added_reg->invalidate_regs[0], b1);
+  EXPECT_EQ(added_reg->invalidate_regs[1], i1);
+  EXPECT_EQ(added_reg->invalidate_regs[2], LLDB_INVALID_REGNUM);
+}