Index: clang/include/clang/Basic/Attr.td
===================================================================
--- clang/include/clang/Basic/Attr.td
+++ clang/include/clang/Basic/Attr.td
@@ -1073,7 +1073,7 @@
 def Cold : InheritableAttr {
   let Spellings = [GCC<"cold">];
   let Subjects = SubjectList<[Function]>;
-  let Documentation = [Undocumented];
+  let Documentation = [ColdFunctionEntryDocs];
   let SimpleHandler = 1;
 }
 
@@ -1519,7 +1519,7 @@
 def Hot : InheritableAttr {
   let Spellings = [GCC<"hot">];
   let Subjects = SubjectList<[Function]>;
-  let Documentation = [Undocumented];
+  let Documentation = [HotFunctionEntryDocs];
   let SimpleHandler = 1;
 }
 def : MutualExclusions<[Hot, Cold]>;
Index: clang/include/clang/Basic/AttrDocs.td
===================================================================
--- clang/include/clang/Basic/AttrDocs.td
+++ clang/include/clang/Basic/AttrDocs.td
@@ -5241,6 +5241,21 @@
 }];
 }
 
+def HotFunctionEntryDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+``__attribute__((hot))`` marks a function as hot, as a manual alternative to PGO hotness data.
+If PGO data is available, the annotation ``__attribute__((hot))`` overrides the profile count based hotness (unlike ``__attribute__((cold))``).
+}];
+}
+
+def ColdFunctionEntryDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+``__attribute__((cold))`` marks a function as cold, as a manual alternative to PGO hotness data.
+If PGO data is available, the profile count based hotness overrides the ``__attribute__((cold))`` annotation (unlike ``__attribute__((hot))``).
+}];
+}
 def TransparentUnionDocs : Documentation {
   let Category = DocCatDecl;
   let Content = [{