Index: cmake/modules/HandleLLVMOptions.cmake
===================================================================
--- cmake/modules/HandleLLVMOptions.cmake	(revision 126745)
+++ cmake/modules/HandleLLVMOptions.cmake	(working copy)
@@ -134,6 +134,13 @@
     -w14062 # Promote "enumerator in switch of enum is not handled" to level 1 warning.
     )
 
+  if (LLVM_ENABLE_MULTIPROCESSORCOMPILATION)
+    add_llvm_definitions( /MP )
+    message("Multi processor compilation enabled.")
+  else (LLVM_ENABLE_MULTIPROCESSORCOMPILATION)
+    message("Multi processor compilation disabled.")
+  endif (LLVM_ENABLE_MULTIPROCESSORCOMPILATION)
+
   # Enable warnings
   if (LLVM_ENABLE_WARNINGS)
     add_llvm_definitions( /W4 /Wall )
Index: CMakeLists.txt
===================================================================
--- CMakeLists.txt	(revision 126745)
+++ CMakeLists.txt	(working copy)
@@ -133,6 +133,10 @@
 
 include(AddLLVMDefinitions)
 
+if( MSVC )
+  option(LLVM_ENABLE_MULTIPROCESSORCOMPILATION "Enable multiprocessor compilation." ON)
+endif()
+
 option(LLVM_ENABLE_PIC "Build Position-Independent Code" ON)
 
 include(config-ix)