diff --git a/llvm/runtimes/CMakeLists.txt b/llvm/runtimes/CMakeLists.txt
--- a/llvm/runtimes/CMakeLists.txt
+++ b/llvm/runtimes/CMakeLists.txt
@@ -38,10 +38,10 @@
   set(LLVM_EXTERNAL_${canon_name}_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../../${proj}")
 endforeach()
 
-function(get_compiler_rt_path path)
+function(get_runtime_path runtime path)
   foreach(entry ${runtimes})
     get_filename_component(projName ${entry} NAME)
-    if("${projName}" MATCHES "compiler-rt")
+    if("${projName}" MATCHES "${runtime}")
       set(${path} ${entry} PARENT_SCOPE)
       return()
     endif()
@@ -68,18 +68,6 @@
     "${CMAKE_CURRENT_SOURCE_DIR}/../cmake/modules"
   )
 
-  # Some of the runtimes will conditionally use the compiler-rt sanitizers
-  # to make this work smoothly we ensure that compiler-rt is added first in
-  # the list of sub-projects. This allows other sub-projects to have checks
-  # like `if(TARGET asan)` to enable building with asan.
-  get_compiler_rt_path(compiler_rt_path)
-  if(compiler_rt_path)
-    list(REMOVE_ITEM runtimes ${compiler_rt_path})
-    if(NOT DEFINED LLVM_BUILD_COMPILER_RT OR LLVM_BUILD_COMPILER_RT)
-      list(INSERT runtimes 0 ${compiler_rt_path})
-    endif()
-  endif()
-
   # Setting these variables will allow the sub-build to put their outputs into
   # the library and bin directories of the top-level build.
   set(LLVM_LIBRARY_OUTPUT_INTDIR ${LLVM_LIBRARY_DIR})
@@ -122,6 +110,17 @@
     include(UseLibtool)
   endif()
 
+  # Re-order runtimes in the order of dependencies: libcxxabi depend on libunwind,
+  # libcxx depends on libcxxabi, some compiler-rt runtimes depend on libcxx. This
+  # allows these runtimes to have checks like `if(TARGET ${runtime})`.
+  foreach(runtime compiler-rt libcxx libcxxabi libunwind)
+    get_runtime_path(${runtime} runtime_path)
+    if(runtime_path)
+      list(REMOVE_ITEM runtimes ${runtime_path})
+      list(INSERT runtimes 0 ${runtime_path})
+    endif()
+  endforeach()
+
   # This can be used to detect whether we're in the runtimes build.
   set(RUNTIMES_BUILD ON)
 
@@ -291,7 +290,7 @@
   # If compiler-rt is present we need to build the builtin libraries first. This
   # is required because the other runtimes need the builtin libraries present
   # before the just-built compiler can pass the configuration tests.
-  get_compiler_rt_path(compiler_rt_path)
+  get_runtime_path(compiler-rt compiler_rt_path)
   if(compiler_rt_path)
     if(NOT LLVM_BUILTIN_TARGETS)
       builtin_default_target(${compiler_rt_path}