diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -15131,7 +15131,17 @@
 If the intrinsic call has the 'reassoc' or 'fast' flags set, then the
 reduction will not preserve the associativity of an equivalent scalarized
 counterpart. Otherwise the reduction will be *ordered*, thus implying that
-the operation respects the associativity of a scalarized reduction.
+the operation respects the associativity of a scalarized reduction. That is, the
+reduction begins with the start value and performs an fadd operation with consecutively
+increasing vector element indices. See the following pseudocode:
+
+::
+
+    float ordered_fadd(start_value, input_vector)
+      result = start_value
+      for i = 0 to length(input_vector)
+        result = result + input_vector[i]
+      return result
 
 
 Arguments:
@@ -15192,7 +15202,17 @@
 If the intrinsic call has the 'reassoc' or 'fast' flags set, then the
 reduction will not preserve the associativity of an equivalent scalarized
 counterpart. Otherwise the reduction will be *ordered*, thus implying that
-the operation respects the associativity of a scalarized reduction.
+the operation respects the associativity of a scalarized reduction. That is, the
+reduction begins with the start value and performs an fmul operation with consecutively
+increasing vector element indices. See the following pseudocode:
+
+::
+
+    float ordered_fmul(start_value, input_vector)
+      result = start_value
+      for i = 0 to length(input_vector)
+        result = result * input_vector[i]
+      return result
 
 
 Arguments: