diff --git a/lldb/test/API/CMakeLists.txt b/lldb/test/API/CMakeLists.txt
--- a/lldb/test/API/CMakeLists.txt
+++ b/lldb/test/API/CMakeLists.txt
@@ -122,13 +122,13 @@
   endif()
 endif()
 
-set(LLDB_DOTEST_ARGS ${LLDB_TEST_COMMON_ARGS};${LLDB_TEST_USER_ARGS} CACHE INTERNAL STRING)
 set(dotest_args_replacement ${LLVM_BUILD_MODE})
 
 if(LLDB_BUILT_STANDALONE)
   # In paths to our build-tree, replace CMAKE_CFG_INTDIR with our configuration name placeholder.
   string(REPLACE ${CMAKE_CFG_INTDIR} ${LLVM_BUILD_MODE} config_runtime_output_dir ${LLVM_RUNTIME_OUTPUT_INTDIR})
-  string(REPLACE ${LLVM_RUNTIME_OUTPUT_INTDIR} ${config_runtime_output_dir} LLDB_DOTEST_ARGS "${LLDB_DOTEST_ARGS}")
+  string(REPLACE ${LLVM_RUNTIME_OUTPUT_INTDIR} ${config_runtime_output_dir} LLDB_TEST_COMMON_ARGS "${LLDB_TEST_COMMON_ARGS}")
+  string(REPLACE ${LLVM_RUNTIME_OUTPUT_INTDIR} ${config_runtime_output_dir} LLDB_TEST_USER_ARGS "${LLDB_TEST_USER_ARGS}")
   string(REPLACE ${LLVM_RUNTIME_OUTPUT_INTDIR} ${config_runtime_output_dir} LLDB_SOURCE_DIR "${LLDB_SOURCE_DIR}")
   string(REPLACE ${LLVM_RUNTIME_OUTPUT_INTDIR} ${config_runtime_output_dir} LLDB_FRAMEWORK_DIR "${LLDB_FRAMEWORK_DIR}")
   string(REPLACE ${LLVM_RUNTIME_OUTPUT_INTDIR} ${config_runtime_output_dir} LLDB_TEST_BUILD_DIRECTORY "${LLDB_TEST_BUILD_DIRECTORY}")
@@ -155,7 +155,8 @@
   endif()
 endif()
 
-string(REPLACE ${CMAKE_CFG_INTDIR} ${dotest_args_replacement} LLDB_DOTEST_ARGS "${LLDB_DOTEST_ARGS}")
+string(REPLACE ${CMAKE_CFG_INTDIR} ${dotest_args_replacement} LLDB_TEST_COMMON_ARGS "${LLDB_TEST_COMMON_ARGS}")
+string(REPLACE ${CMAKE_CFG_INTDIR} ${dotest_args_replacement} LLDB_TEST_USER_ARGS "${LLDB_TEST_USER_ARGS}")
 string(REPLACE ${CMAKE_CFG_INTDIR} ${dotest_args_replacement} LLDB_SOURCE_DIR "${LLDB_SOURCE_DIR}")
 string(REPLACE ${CMAKE_CFG_INTDIR} ${dotest_args_replacement} LLDB_TEST_BUILD_DIRECTORY "${LLDB_TEST_BUILD_DIRECTORY}")
 string(REPLACE ${CMAKE_CFG_INTDIR} ${dotest_args_replacement} LLDB_TEST_EXECUTABLE "${LLDB_TEST_EXECUTABLE}")
diff --git a/lldb/test/API/lit.cfg.py b/lldb/test/API/lit.cfg.py
--- a/lldb/test/API/lit.cfg.py
+++ b/lldb/test/API/lit.cfg.py
@@ -155,8 +155,8 @@
 # Build dotest command.
 dotest_cmd = [os.path.join(config.lldb_src_root, 'test', 'API', 'dotest.py')]
 
-if is_configured('dotest_args_str'):
-  dotest_cmd.extend(config.dotest_args_str.split(';'))
+if is_configured('dotest_common_args_str'):
+  dotest_cmd.extend(config.dotest_common_args_str.split(';'))
 
 # Library path may be needed to locate just-built clang and libcxx.
 if is_configured('llvm_libs_dir'):
@@ -235,6 +235,20 @@
   for plugin in config.enabled_plugins:
     dotest_cmd += ['--enable-plugin', plugin]
 
+# `dotest` args come from three different sources:
+# 1. Derived by CMake based on its configs (LLDB_TEST_COMMON_ARGS), which end
+# up in `dotest_common_args_str`.
+# 2. CMake user parameters (LLDB_TEST_USER_ARGS), which end up in
+# `dotest_user_cmake_args_str`.
+# 3. With `llvm-lit "--param=dotest-args=..."`, which end up in
+# `dotest_lit_args_str`.
+# Check them in this order, so that more specific overrides are visited last.
+# In particular, (1) is visited at the top of the file, since the script
+# derives other information from it.
+
+if is_configured('dotest_user_cmake_args_str'):
+  dotest_cmd.extend(config.dotest_user_cmake_args_str.split(';'))
+
 if is_configured('dotest_lit_args_str'):
   # We don't want to force users passing arguments to lit to use `;` as a
   # separator. We use Python's simple lexical analyzer to turn the args into a
diff --git a/lldb/test/API/lit.site.cfg.py.in b/lldb/test/API/lit.site.cfg.py.in
--- a/lldb/test/API/lit.site.cfg.py.in
+++ b/lldb/test/API/lit.site.cfg.py.in
@@ -22,7 +22,8 @@
 config.python_executable = "@Python3_EXECUTABLE@"
 config.lua_executable = "@Lua_EXECUTABLE@"
 config.lua_test_entry = "TestLuaAPI.py"
-config.dotest_args_str = lit_config.substitute("@LLDB_DOTEST_ARGS@")
+config.dotest_common_args_str = lit_config.substitute("@LLDB_TEST_COMMON_ARGS@")
+config.dotest_user_cmake_args_str = lit_config.substitute("@LLDB_TEST_USER_ARGS@")
 config.lldb_enable_python = @LLDB_ENABLE_PYTHON@
 config.dotest_lit_args_str = None
 config.enabled_plugins = []