diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -3140,6 +3140,23 @@
 IEEE-754-2008 specifications for binary16, binary32, binary64, and binary128
 respectively.
 
+X86_amx Type
+""""""""""""
+
+:Overview:
+
+The x86_amx type represents a value held in an AMX tile register on an x86
+machine. The operations allowed on it are quite limited: stride load and store,
+zero, dot product. User-specified AMX instructions are represented as intrinsic.
+There are no arrays, vectors or constants of this type.
+
+:Syntax:
+
+::
+
+      x86_amx
+
+
 X86_mmx Type
 """"""""""""
 
@@ -3534,7 +3551,7 @@
 format is represented by ``0xR`` followed by 4 hexadecimal digits. All
 hexadecimal formats are big-endian (sign bit at the left).
 
-There are no constants of type x86_mmx.
+There are no constants of type x86_mmx and x86_amx.
 
 .. _complexconstants: