diff --git a/llvm/lib/Transforms/IPO/Attributor.cpp b/llvm/lib/Transforms/IPO/Attributor.cpp
--- a/llvm/lib/Transforms/IPO/Attributor.cpp
+++ b/llvm/lib/Transforms/IPO/Attributor.cpp
@@ -72,6 +72,7 @@
           "Number of function arguments marked dereferenceable");
 STATISTIC(NumCSArgumentDereferenceable,
           "Number of call site arguments marked dereferenceable");
+STATISTIC(NumFnNoReturn, "Number of functions marked noreturn");
 
 // TODO: Determine a good default value.
 //
@@ -160,6 +161,9 @@
   case Attribute::WillReturn:
     NumFnWillReturn++;
     break;
+  case Attribute::NoReturn:
+    NumFnNoReturn++;
+    return;
   case Attribute::NoAlias:
     NumFnArgumentNoAlias++;
     return;
@@ -1978,6 +1982,63 @@
                                                        : ChangeStatus::CHANGED;
 }
 
+/// ------------------ Function No-Return Attribute ----------------------------
+struct AANoReturnFunction final : public AANoReturn, BooleanState {
+
+  AANoReturnFunction(Function &F, InformationCache &InfoCache)
+      : AANoReturn(F, InfoCache) {}
+
+  /// See AbstractAttribute::getState()
+  /// {
+  AbstractState &getState() override { return *this; }
+  const AbstractState &getState() const override { return *this; }
+  /// }
+
+  /// Return true if the underlying object is known to never return.
+  bool isKnownNoReturn() const override { return getKnown(); }
+
+  /// Return true if the underlying object is assumed to never return.
+  bool isAssumedNoReturn() const override { return getAssumed(); }
+
+  /// See AbstractAttribute::getManifestPosition().
+  ManifestPosition getManifestPosition() const override { return MP_FUNCTION; }
+
+  /// See AbstractAttribute::getAsStr().
+  const std::string getAsStr() const override {
+    return getAssumed() ? "noreturn" : "may-return";
+  }
+
+  /// See AbstractAttribute::initialize(...).
+  void initialize(Attributor &A) override {
+    Function &F = getAnchorScope();
+    if (F.hasFnAttribute(getAttrKind()))
+      indicateOptimisticFixpoint();
+  }
+
+  /// See AbstractAttribute::updateImpl(Attributor &A).
+  virtual ChangeStatus updateImpl(Attributor &A) override {
+    Function &F = getAnchorScope();
+
+    std::function<bool(Value &)> Pred = [](Value &) {
+      // Any potential return value means the function might return, thus it
+      // is not "no-return".
+      return false;
+    };
+
+    // Use the absence of returned values to justify no-return.
+    auto *AARetVal = A.getAAFor<AAReturnedValues>(*this, F);
+    if (AARetVal && AARetVal->checkForallReturnedValues(Pred)) {
+      if (AARetVal->getState().isAtFixpoint())
+        indicateOptimisticFixpoint();
+      return ChangeStatus::UNCHANGED;
+    }
+
+    // Fallthrough, reached if we failed to keep the no-capture state.
+    indicatePessimisticFixpoint();
+    return ChangeStatus::CHANGED;
+  }
+};
+
 /// ----------------------------------------------------------------------------
 ///                               Attributor
 /// ----------------------------------------------------------------------------
@@ -2166,6 +2227,9 @@
   // Every function might be "no-free".
   registerAA(*new AANoFreeFunction(F, InfoCache));
 
+  // Every function might be "no-return".
+  registerAA(*new AANoReturnFunction(F, InfoCache));
+
   // Return attributes are only appropriate if the return type is non void.
   Type *ReturnType = F.getReturnType();
   if (!ReturnType->isVoidTy()) {
diff --git a/llvm/test/Transforms/FunctionAttrs/arg_nocapture.ll b/llvm/test/Transforms/FunctionAttrs/arg_nocapture.ll
--- a/llvm/test/Transforms/FunctionAttrs/arg_nocapture.ll
+++ b/llvm/test/Transforms/FunctionAttrs/arg_nocapture.ll
@@ -1,5 +1,4 @@
 ; RUN: opt -functionattrs -attributor -attributor-disable=false -S < %s | FileCheck %s
-; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-verify=true -S < %s | FileCheck %s
 ;
 ; Test cases specifically designed for the "no-capture" argument attribute.
 ; We use FIXME's to indicate problems and missing attributes.
diff --git a/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll b/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll
--- a/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll
+++ b/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll
@@ -1,19 +1,12 @@
 ; RUN: opt -functionattrs -attributor -attributor-disable=false -S < %s | FileCheck %s
-; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-verify=true -S < %s | FileCheck %s
 ;
 ; Test cases specifically designed for the "no-return" function attribute.
 ; We use FIXME's to indicate problems and missing attributes.
-;
-; TEST 1: singleton SCC void return type
-; TEST 2: singleton SCC int return type with a lot of recursive calls
-; TEST 3: endless loop, no return instruction
-; TEST 4: endless loop, dead return instruction
-; TEST 5: all paths contain a no-return function call
-;
+
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
 
-; TEST 1
+; TEST 1, singleton SCC void return type
 ;
 ; void srec0() {
 ;   return srec0();
@@ -30,14 +23,13 @@
 }
 
 
-; TEST 2
+; TEST 2: singleton SCC int return type with a lot of recursive calls
 ;
 ; int srec16(int a) {
 ;   return srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(srec16(a))))))))))))))));
 ; }
 ;
-; FIXME: no-return missing
-; CHECK: Function Attrs: nofree noinline nosync nounwind readnone uwtable
+; CHECK: Function Attrs: nofree noinline noreturn nosync nounwind readnone uwtable
 ; CHECK: define i32 @srec16(i32 %a)
 ;
 define i32 @srec16(i32 %a) #0 {
@@ -58,18 +50,20 @@
   %call13 = call i32 @srec16(i32 %call12)
   %call14 = call i32 @srec16(i32 %call13)
   %call15 = call i32 @srec16(i32 %call14)
+  br label %exit
+
+exit:
   ret i32 %call15
 }
 
 
-; TEST 3
+; TEST 3: endless loop, no return instruction
 ;
 ; int endless_loop(int a) {
 ;   while (1);
 ; }
 ;
-; FIXME: no-return missing
-; CHECK: Function Attrs: nofree noinline norecurse nosync nounwind readnone uwtable
+; CHECK: Function Attrs: nofree noinline norecurse noreturn nosync nounwind readnone uwtable
 ; CHECK: define i32 @endless_loop(i32 %a)
 ;
 define i32 @endless_loop(i32 %a) #0 {
@@ -81,14 +75,14 @@
 }
 
 
-; TEST 4
+; TEST 4: endless loop, dead return instruction
 ;
 ; int endless_loop(int a) {
 ;   while (1);
 ;   return a;
 ; }
 ;
-; FIXME: no-return missing
+; FIXME: no-return missing (D65243 should fix this)
 ; CHECK: Function Attrs: nofree noinline norecurse nosync nounwind readnone uwtable
 ; CHECK: define i32 @dead_return(i32 returned %a)
 ;
@@ -104,14 +98,13 @@
 }
 
 
-; TEST 5
+; TEST 5: all paths contain a no-return function call
 ;
 ; int multiple_noreturn_calls(int a) {
 ;   return a == 0 ? endless_loop(a) : srec16(a);
 ; }
 ;
-; FIXME: no-return missing
-; CHECK: Function Attrs: nofree noinline nosync nounwind readnone uwtable
+; CHECK: Function Attrs: nofree noinline noreturn nosync nounwind readnone uwtable
 ; CHECK: define i32 @multiple_noreturn_calls(i32 %a)
 ;
 define i32 @multiple_noreturn_calls(i32 %a) #0 {