diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index c5d3e23a47f0e..18b6ee85fae8d 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -545,6 +545,9 @@ set(LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING "DISABLED" CACHE STRING
   "Enhance Debugify's line number coverage tracking; enabling this is ABI-breaking. Can be DISABLED, or COVERAGE.")
 set_property(CACHE LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING PROPERTY STRINGS DISABLED COVERAGE)
 
+option(LLVM_EXPERIMENTAL_KEY_INSTRUCTIONS
+  "Add additional fields to DILocations to support Key Instructions" OFF)
+
 set(WINDOWS_PREFER_FORWARD_SLASH_DEFAULT OFF)
 if (MINGW)
   # Cygwin doesn't identify itself as Windows, and thus gets path::Style::posix
diff --git a/llvm/cmake/modules/HandleLLVMOptions.cmake b/llvm/cmake/modules/HandleLLVMOptions.cmake
index 5db06ccdadbeb..c2c04051ef3ce 100644
--- a/llvm/cmake/modules/HandleLLVMOptions.cmake
+++ b/llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -206,6 +206,10 @@ else()
   message(FATAL_ERROR "Unknown value for LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING: \"${LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING}\"!")
 endif()
 
+if(LLVM_EXPERIMENTAL_KEY_INSTRUCTIONS)
+  add_compile_definitions(EXPERIMENTAL_KEY_INSTRUCTIONS)
+endif()
+
 if( LLVM_REVERSE_ITERATION )
   set( LLVM_ENABLE_REVERSE_ITERATION 1 )
 endif()