diff --git a/clang/docs/LanguageExtensions.rst b/clang/docs/LanguageExtensions.rst
--- a/clang/docs/LanguageExtensions.rst
+++ b/clang/docs/LanguageExtensions.rst
@@ -3410,6 +3410,9 @@
 
 Unrolling of a loop can be prevented by specifying ``unroll(disable)``.
 
+Loop unroll parameters can be controlled by options
+`-mllvm -unroll-count=n` and `-mllvm -pragma-unroll-threshold=n`.
+
 Loop Distribution
 -----------------