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diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index ff456102664..b953dbd0f17 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -13764,6 +13764,73 @@ Examples
       %res = call i4 @llvm.smul.fix.sat.i4(i4 2, i4 4, i32 1)  ; %res = 4 (1 x 2 = 2)
 
 
+'``llvm.umul.fix.sat.*``' Intrinsics
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax
+"""""""
+
+This is an overloaded intrinsic. You can use ``llvm.umul.fix.sat``
+on any integer bit width or vectors of integers.
+
+::
+
+      declare i16 @llvm.umul.fix.sat.i16(i16 %a, i16 %b, i32 %scale)
+      declare i32 @llvm.umul.fix.sat.i32(i32 %a, i32 %b, i32 %scale)
+      declare i64 @llvm.umul.fix.sat.i64(i64 %a, i64 %b, i32 %scale)
+      declare <4 x i32> @llvm.umul.fix.sat.v4i32(<4 x i32> %a, <4 x i32> %b, i32 %scale)
+
+Overview
+"""""""""
+
+The '``llvm.umul.fix.sat``' family of intrinsic functions perform unsigned
+fixed point saturation multiplication on 2 arguments of the same scale.
+
+Arguments
+""""""""""
+
+The arguments (%a and %b) and the result may be of integer types of any bit
+width, but they must have the same bit width. ``%a`` and ``%b`` are the two
+values that will undergo unsigned fixed point multiplication. The argument
+``%scale`` represents the scale of both operands, and must be a constant
+integer.
+
+Semantics:
+""""""""""
+
+This operation performs fixed point multiplication on the 2 arguments of a
+specified scale. The result will also be returned in the same scale specified
+in the third argument.
+
+If the result value cannot be precisely represented in the given scale, the
+value is rounded up or down to the closest representable value. The rounding
+direction is unspecified.
+
+The maximum value this operation can clamp to is the largest unsigned value
+representable by the bit width of the first 2 arguments. The minimum value is the
+smallest unsigned value representable by this bit width (zero).
+
+
+Examples
+"""""""""
+
+.. code-block:: llvm
+
+      %res = call i4 @llvm.umul.fix.sat.i4(i4 3, i4 2, i32 0)  ; %res = 6 (2 x 3 = 6)
+      %res = call i4 @llvm.umul.fix.sat.i4(i4 3, i4 2, i32 1)  ; %res = 3 (1.5 x 1 = 1.5)
+
+      ; The result in the following could be rounded down to 2 or up to 2.5
+      %res = call i4 @llvm.umul.fix.sat.i4(i4 3, i4 3, i32 1)  ; %res = 4 (or 5) (1.5 x 1.5 = 2.25)
+
+      ; Saturation
+      %res = call i4 @llvm.umul.fix.sat.i4(i4 8, i4 2, i32 0)  ; %res = 15 (8 x 2 -> clamped to 15)
+      %res = call i4 @llvm.umul.fix.sat.i4(i4 8, i4 8, i32 2)  ; %res = 15 (2 x 2 -> clamped to 3.75)
+
+      ; Scale can affect the saturation result
+      %res = call i4 @llvm.umul.fix.sat.i4(i4 2, i4 4, i32 0)  ; %res = 7 (2 x 4 -> clamped to 7)
+      %res = call i4 @llvm.umul.fix.sat.i4(i4 2, i4 4, i32 1)  ; %res = 4 (1 x 2 = 2)
+
+
 Specialised Arithmetic Intrinsics
 ---------------------------------