diff --git a/llvm/docs/CMake.rst b/llvm/docs/CMake.rst
--- a/llvm/docs/CMake.rst
+++ b/llvm/docs/CMake.rst
@@ -225,6 +225,12 @@
   targets. Case-sensitive. Defaults to *all*. Example:
   ``-DLLVM_TARGETS_TO_BUILD="X86;PowerPC"``.
 
+**LLVM_EXPERIMENTAL_TARGETS_TO_BUILD**:STRING
+  Semicolon-separated list of experimental targets to build and linked into 
+  llvm. This will build the experimental target without needing to add it 
+  to the list of all the targets. Once the target becomes stable, It can be 
+  added to the LLVM_ALL_TARGETS variable located in the main CMakeLists.txt.
+  
 **LLVM_BUILD_TOOLS**:BOOL
   Build LLVM tools. Defaults to ON. Targets for building each tool are generated
   in any case. You can build a tool separately by invoking its target. For