diff --git a/lldb/CMakeLists.txt b/lldb/CMakeLists.txt
--- a/lldb/CMakeLists.txt
+++ b/lldb/CMakeLists.txt
@@ -88,10 +88,6 @@
     list(APPEND LLDB_TEST_DEPS lldb-server)
   endif()
 
-  if(TARGET debugserver)
-    list(APPEND LLDB_TEST_DEPS debugserver)
-  endif()
-
   if(TARGET lldb-mi)
     list(APPEND LLDB_TEST_DEPS lldb-mi)
   endif()
diff --git a/lldb/cmake/modules/AddLLDB.cmake b/lldb/cmake/modules/AddLLDB.cmake
--- a/lldb/cmake/modules/AddLLDB.cmake
+++ b/lldb/cmake/modules/AddLLDB.cmake
@@ -275,3 +275,27 @@
     INSTALL_RPATH "${LIST_INSTALL_RPATH}"
   )
 endfunction()
+
+function(lldb_find_system_debugserver path)
+  execute_process(COMMAND xcode-select -p
+                  RESULT_VARIABLE exit_code
+                  OUTPUT_VARIABLE xcode_dev_dir
+                  ERROR_VARIABLE error_msg)
+  if(exit_code)
+    message(WARNING "`xcode-select -p` failed:\n${error_msg}")
+  else()
+    string(STRIP ${xcode_dev_dir} xcode_dev_dir)
+    set(subdir "LLDB.framework/Resources/debugserver")
+    set(path_shared "${xcode_dev_dir}/../SharedFrameworks/${subdir}")
+    set(path_private "${xcode_dev_dir}/Library/PrivateFrameworks/${subdir}")
+
+    if(EXISTS ${path_shared})
+      set(${path} ${path_shared} PARENT_SCOPE)
+    elseif(EXISTS ${path_private})
+      set(${path} ${path_private} PARENT_SCOPE)
+    else()
+      message(WARNING "System debugserver requested, but not found. "
+                      "Candidates don't exist: ${path_shared}\n${path_private}")
+    endif()
+  endif()
+endfunction()
diff --git a/lldb/cmake/modules/LLDBConfig.cmake b/lldb/cmake/modules/LLDBConfig.cmake
--- a/lldb/cmake/modules/LLDBConfig.cmake
+++ b/lldb/cmake/modules/LLDBConfig.cmake
@@ -50,6 +50,7 @@
 option(LLDB_USE_ENTITLEMENTS "When codesigning, use entitlements if available" ON)
 option(LLDB_BUILD_FRAMEWORK "Build LLDB.framework (Darwin only)" OFF)
 option(LLDB_NO_INSTALL_DEFAULT_RPATH "Disable default RPATH settings in binaries" OFF)
+option(LLDB_USE_SYSTEM_DEBUGSERVER "Use the system's debugserver for testing (Darwin only)." OFF)
 
 if(LLDB_BUILD_FRAMEWORK)
   if(NOT APPLE)
diff --git a/lldb/test/CMakeLists.txt b/lldb/test/CMakeLists.txt
--- a/lldb/test/CMakeLists.txt
+++ b/lldb/test/CMakeLists.txt
@@ -74,15 +74,6 @@
   endif()
 endif()
 
-if(LLDB_CODESIGN_IDENTITY_USED)
-  list(APPEND LLDB_TEST_COMMON_ARGS --codesign-identity "${LLDB_CODESIGN_IDENTITY_USED}")
-endif()
-
-if(LLDB_BUILD_FRAMEWORK)
-  get_target_property(framework_target_dir liblldb LIBRARY_OUTPUT_DIRECTORY)
-  list(APPEND LLDB_TEST_COMMON_ARGS --framework ${framework_target_dir}/LLDB.framework)
-endif()
-
 if (NOT ${CMAKE_SYSTEM_NAME} MATCHES "Windows|Darwin")
   list(APPEND LLDB_TEST_COMMON_ARGS
     --env ARCHIVER=${CMAKE_AR} --env OBJCOPY=${CMAKE_OBJCOPY})
@@ -94,12 +85,29 @@
   endif()
 endif()
 
-if(CMAKE_HOST_APPLE AND DEBUGSERVER_PATH)
-  list(APPEND LLDB_TEST_COMMON_ARGS --server ${DEBUGSERVER_PATH})
-endif()
+if(CMAKE_HOST_APPLE)
+  if(LLDB_BUILD_FRAMEWORK)
+    get_target_property(framework_build_dir liblldb LIBRARY_OUTPUT_DIRECTORY)
+    list(APPEND LLDB_TEST_COMMON_ARGS --framework ${framework_build_dir}/LLDB.framework)
+  endif()
+
+  # Use the same identity for testing
+  get_property(code_sign_identity_used GLOBAL PROPERTY LLDB_DEBUGSERVER_CODESIGN_IDENTITY)
+  if(code_sign_identity_used)
+    list(APPEND LLDB_TEST_COMMON_ARGS --codesign-identity "${code_sign_identity_used}")
+  endif()
+
+  if(LLDB_USE_SYSTEM_DEBUGSERVER)
+    lldb_find_system_debugserver(debugserver_path)
+    message(STATUS "LLDB tests use out-of-tree debugserver: ${debugserver_path}")
+    list(APPEND LLDB_TEST_COMMON_ARGS --out-of-tree-debugserver)
+  else()
+    set(debugserver_path ${LLVM_RUNTIME_OUTPUT_INTDIR}/debugserver)
+    message(STATUS "LLDB Tests use just-built debugserver: ${debugserver_path}")
+    add_dependencies(lldb-test-deps debugserver)
+  endif()
 
-if(SKIP_TEST_DEBUGSERVER)
-  list(APPEND LLDB_TEST_COMMON_ARGS --out-of-tree-debugserver)
+  list(APPEND LLDB_TEST_COMMON_ARGS --server ${debugserver_path})
 endif()
 
 set(LLDB_DOTEST_ARGS ${LLDB_TEST_COMMON_ARGS};${LLDB_TEST_USER_ARGS})
diff --git a/lldb/tools/debugserver/source/CMakeLists.txt b/lldb/tools/debugserver/source/CMakeLists.txt
--- a/lldb/tools/debugserver/source/CMakeLists.txt
+++ b/lldb/tools/debugserver/source/CMakeLists.txt
@@ -6,6 +6,58 @@
 
 include_directories(MacOSX)
 
+function(check_certificate identity result_valid)
+  execute_process(
+    COMMAND security find-certificate -Z -p -c ${identity} /Library/Keychains/System.keychain
+    RESULT_VARIABLE exit_code OUTPUT_QUIET ERROR_QUIET)
+  if(exit_code)
+    set(${result_valid} FALSE PARENT_SCOPE)
+  else()
+    set(${result_valid} TRUE PARENT_SCOPE)
+  endif()
+endfunction()
+
+function(get_debugserver_codesign_identity result)
+  string(CONCAT not_found_help
+    "This will cause failures in the test suite."
+    "Pass '-DLLDB_USE_SYSTEM_DEBUGSERVER=ON' to use the system one instead."
+    "See 'Code Signing on macOS' in the documentation."
+  )
+
+  # Explicit override: always use it, but warn if unavailable and used for testing
+  if(LLDB_CODESIGN_IDENTITY)
+    set(${result} ${LLDB_CODESIGN_IDENTITY} PARENT_SCOPE)
+    check_certificate(${LLDB_CODESIGN_IDENTITY} available)
+    if(NOT available AND NOT LLDB_USE_SYSTEM_DEBUGSERVER)
+      message(WARNING "LLDB_CODESIGN_IDENTITY not found: '${LLDB_CODESIGN_IDENTITY}' ${not_found_help}")
+    endif()
+    return()
+  endif()
+
+  # Development signing identity: use if available
+  check_certificate(lldb_codesign available)
+  if(available)
+    set(${result} lldb_codesign PARENT_SCOPE)
+    return()
+  endif()
+
+  if(NOT LLDB_USE_SYSTEM_DEBUGSERVER)
+    message(WARNING "Development code sign identiy not found: 'lldb_codesign' ${not_found_help}")
+  endif()
+
+  # LLVM pendant: fallback if available
+  if(LLVM_CODESIGNING_IDENTITY)
+    check_certificate(${LLVM_CODESIGNING_IDENTITY} available)
+    if(available)
+      set(${result} ${LLVM_CODESIGNING_IDENTITY} PARENT_SCOPE)
+      return()
+    endif()
+  endif()
+
+  # Ad-hoc signing: last resort
+  set(${result} "-" PARENT_SCOPE)
+endfunction()
+
 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -stdlib=libc++ -Wl,-sectcreate,__TEXT,__info_plist,${CMAKE_CURRENT_SOURCE_DIR}/../resources/lldb-debugserver-Info.plist")
 
 check_cxx_compiler_flag("-Wno-gnu-zero-variadic-macro-arguments"
@@ -30,132 +82,17 @@
 
 add_subdirectory(MacOSX)
 
-# LLDB-specific identity, currently used for code signing debugserver.
 set(LLDB_CODESIGN_IDENTITY "" CACHE STRING
-    "Override code sign identity for debugserver and for use in tests; falls back to LLVM_CODESIGNING_IDENTITY if set or lldb_codesign otherwise (Darwin only)")
-
-# Determine which identity to use and store it in the separate cache entry.
-# We will query it later for LLDB_TEST_COMMON_ARGS.
-if(LLDB_CODESIGN_IDENTITY)
-  set(LLDB_CODESIGN_IDENTITY_USED ${LLDB_CODESIGN_IDENTITY} CACHE INTERNAL "" FORCE)
-elseif(LLVM_CODESIGNING_IDENTITY)
-  set(LLDB_CODESIGN_IDENTITY_USED ${LLVM_CODESIGNING_IDENTITY} CACHE INTERNAL "" FORCE)
-else()
-  set(LLDB_CODESIGN_IDENTITY_USED lldb_codesign CACHE INTERNAL "" FORCE)
-endif()
+    "Identity override for debugserver; see 'Code Signing on macOS' in the documentation (Darwin only)")
 
-# Override locally, so the identity is used for targets created in this scope.
-set(LLVM_CODESIGNING_IDENTITY ${LLDB_CODESIGN_IDENTITY_USED})
-
-option(LLDB_NO_DEBUGSERVER "Disable the debugserver target" OFF)
-option(LLDB_USE_SYSTEM_DEBUGSERVER "Use the system's debugserver instead of building it from source (Darwin only)." OFF)
+get_debugserver_codesign_identity(debugserver_codesign_identity)
 
-# Incompatible options
-if(LLDB_NO_DEBUGSERVER AND LLDB_USE_SYSTEM_DEBUGSERVER)
-  message(FATAL_ERROR "Inconsistent options: LLDB_NO_DEBUGSERVER and LLDB_USE_SYSTEM_DEBUGSERVER")
-endif()
-
-# Try to locate the system debugserver.
-# Subsequent feasibility checks depend on it.
-if(APPLE AND CMAKE_HOST_APPLE)
-  execute_process(
-    COMMAND xcode-select -p
-    OUTPUT_VARIABLE xcode_dev_dir)
-  string(STRIP ${xcode_dev_dir} xcode_dev_dir)
-
-  set(debugserver_rel_path "LLDB.framework/Resources/debugserver")
-  set(debugserver_shared "${xcode_dev_dir}/../SharedFrameworks/${debugserver_rel_path}")
-  set(debugserver_private "${xcode_dev_dir}/Library/PrivateFrameworks/${debugserver_rel_path}")
-
-  if(EXISTS ${debugserver_shared})
-    set(system_debugserver ${debugserver_shared})
-  elseif(EXISTS ${debugserver_private})
-    set(system_debugserver ${debugserver_private})
-  endif()
-endif()
-
-# Handle unavailability
-if(LLDB_USE_SYSTEM_DEBUGSERVER)
-  if(system_debugserver)
-    set(use_system_debugserver ON)
-  elseif(APPLE AND CMAKE_HOST_APPLE)
-    # Binary not found on system. Keep cached variable, to try again on reconfigure.
-    message(SEND_ERROR
-      "LLDB_USE_SYSTEM_DEBUGSERVER option set, but no debugserver found in:\
-        ${debugserver_shared}\
-        ${debugserver_private}")
-  else()
-    # Non-Apple target platform or non-Darwin host. Reset invalid cached variable.
-    message(WARNING "Reverting invalid option LLDB_USE_SYSTEM_DEBUGSERVER (Darwin only)")
-    set(LLDB_USE_SYSTEM_DEBUGSERVER OFF CACHE BOOL "" FORCE)
-  endif()
-elseif(NOT LLDB_NO_DEBUGSERVER)
-  # Default case: on Darwin we need the right code signing ID.
-  # See lldb/docs/code-signing.txt for details.
-  if(CMAKE_HOST_APPLE AND NOT LLVM_CODESIGNING_IDENTITY STREQUAL "lldb_codesign")
-    message(WARNING "Codesigning debugserver with identity ${LLVM_CODESIGNING_IDENTITY}. "
-                    "The usual setup uses the \"lldb_codesign\" identity created with "
-                    "scripts/macos-setup-codesign.sh. As a result your debugserver might "
-                    "not be able to attach to processes.\n"
-                    "Pass -DLLDB_CODESIGN_IDENTITY=lldb_codesign to use the development "
-                    "signing identity.")
-  endif()
-  set(build_and_sign_debugserver ON)
-endif()
-
-# TODO: We don't use the $<TARGET_FILE:debugserver> generator expression here,
-# because the value of DEBUGSERVER_PATH is used to build LLDB_DOTEST_ARGS,
-# which is used for configuring lldb-dotest.in, which does not have a generator
-# step at the moment.
-set(default_debugserver_path "${LLVM_RUNTIME_OUTPUT_INTDIR}/debugserver${CMAKE_EXECUTABLE_SUFFIX}")
-
-# Remember where debugserver binary goes and whether or not we have to test it.
-set(DEBUGSERVER_PATH "" CACHE FILEPATH "Path to debugserver")
-set(SKIP_TEST_DEBUGSERVER OFF CACHE BOOL "Building the in-tree debugserver was skipped")
-
-# Reset values in all cases in order to correctly support reconfigurations.
-if(use_system_debugserver)
-  add_custom_target(debugserver
-    COMMAND ${CMAKE_COMMAND} -E copy_if_different
-            ${system_debugserver} ${LLVM_RUNTIME_OUTPUT_INTDIR}
-    COMMENT "Copying the system debugserver to LLDB's binaries directory.")
-
-  set_target_properties(debugserver PROPERTIES FOLDER "lldb libraries/debugserver")
-
-  # Don't test debugserver itself.
-  # Tests that require debugserver will use the copy.
-  set(DEBUGSERVER_PATH ${default_debugserver_path} CACHE FILEPATH "" FORCE)
-  set(SKIP_TEST_DEBUGSERVER ON CACHE BOOL "" FORCE)
-
-  message(STATUS "Copy system debugserver from: ${system_debugserver}")
-elseif(build_and_sign_debugserver)
-  # Build, sign and test debugserver (below)
-  set(DEBUGSERVER_PATH ${default_debugserver_path} CACHE FILEPATH "" FORCE)
-  set(SKIP_TEST_DEBUGSERVER OFF CACHE BOOL "" FORCE)
-
-  message(STATUS "lldb debugserver: ${DEBUGSERVER_PATH}")
-else()
-  # No tests for debugserver, no tests that require it.
-  set(DEBUGSERVER_PATH "" CACHE FILEPATH "" FORCE)
-  set(SKIP_TEST_DEBUGSERVER ON CACHE BOOL "" FORCE)
-
-  message(STATUS "lldb debugserver will not be available.")
-endif()
+# Override locally, so the identity is used for targets created in this scope.
+set(LLVM_CODESIGNING_IDENTITY ${debugserver_codesign_identity})
 
-# On MacOS, debugserver needs to be codesigned when built. Check if we have
-# a certificate instead of failing in the middle of the build.
-if(build_and_sign_debugserver)
-  execute_process(
-    COMMAND security find-certificate -Z -p -c ${LLDB_CODESIGN_IDENTITY_USED} /Library/Keychains/System.keychain
-    RESULT_VARIABLE cert_return
-    OUTPUT_QUIET
-    ERROR_QUIET)
-
-  if (cert_return)
-    message(FATAL_ERROR "Certificate for debugserver not found. Run scripts/macos-setup-codesign.sh or "
-                        "use the system debugserver passing -DLLDB_USE_SYSTEM_DEBUGSERVER=ON to CMake")
-  endif()
-endif()
+# Use the same identity later in the test suite.
+set_property(GLOBAL PROPERTY
+  LLDB_DEBUGSERVER_CODESIGN_IDENTITY ${debugserver_codesign_identity})
 
 if(APPLE)
   if(IOS)
@@ -190,7 +127,7 @@
   endif()
 endif()
 
-if(build_and_sign_debugserver)
+#if(build_and_sign_debugserver)
   set(generated_mach_interfaces
     ${CMAKE_CURRENT_BINARY_DIR}/mach_exc.h
     ${CMAKE_CURRENT_BINARY_DIR}/mach_excServer.c
@@ -318,4 +255,4 @@
         ${entitlements}
       )
   endif()
-endif()
+#endif()
diff --git a/lldb/unittests/CMakeLists.txt b/lldb/unittests/CMakeLists.txt
--- a/lldb/unittests/CMakeLists.txt
+++ b/lldb/unittests/CMakeLists.txt
@@ -78,6 +78,6 @@
 add_subdirectory(UnwindAssembly)
 add_subdirectory(Utility)
 
-if(LLDB_CAN_USE_DEBUGSERVER AND NOT SKIP_TEST_DEBUGSERVER)
+if(LLDB_CAN_USE_DEBUGSERVER AND NOT LLDB_USE_SYSTEM_DEBUGSERVER)
   add_subdirectory(debugserver)
 endif()
diff --git a/lldb/unittests/tools/lldb-server/CMakeLists.txt b/lldb/unittests/tools/lldb-server/CMakeLists.txt
--- a/lldb/unittests/tools/lldb-server/CMakeLists.txt
+++ b/lldb/unittests/tools/lldb-server/CMakeLists.txt
@@ -13,10 +13,16 @@
 add_lldb_test_executable(thread_inferior inferior/thread_inferior.cpp)
 add_lldb_test_executable(environment_check inferior/environment_check.cpp)
 
-if(DEBUGSERVER_PATH)
-  add_definitions(-DLLDB_SERVER="${DEBUGSERVER_PATH}" -DLLDB_SERVER_IS_DEBUGSERVER=1)
+if(LLDB_CAN_USE_LLDB_SERVER)
+  if(LLDB_USE_SYSTEM_DEBUGSERVER)
+    lldb_find_system_debugserver(system_debugserver_path)
+    add_definitions(-DLLDB_SERVER="${system_debugserver_path}")
+  else()
+    add_definitions(-DLLDB_SERVER="$<TARGET_FILE:lldb-server>")
+  endif()
+  add_definitions(-DLLDB_SERVER_IS_DEBUGSERVER=ON)
 else()
-  add_definitions(-DLLDB_SERVER="$<TARGET_FILE:lldb-server>" -DLLDB_SERVER_IS_DEBUGSERVER=0)
+  add_definitions(-DLLDB_SERVER="$<TARGET_FILE:lldb-server>" -DLLDB_SERVER_IS_DEBUGSERVER=OFF)
 endif()
 
 add_definitions(