Index: clang/lib/CodeGen/CGCall.cpp
===================================================================
--- clang/lib/CodeGen/CGCall.cpp
+++ clang/lib/CodeGen/CGCall.cpp
@@ -4395,10 +4395,13 @@
 
     // Strip away the noreturn attribute to better diagnose unreachable UB.
     if (SanOpts.has(SanitizerKind::Unreachable)) {
+      // Also remove from function since hasFnAttr checks attributes of
+      // instruction and called function.
       if (auto *F = CS.getCalledFunction())
         F->removeFnAttr(llvm::Attribute::NoReturn);
       CS.removeAttribute(llvm::AttributeList::FunctionIndex,
                          llvm::Attribute::NoReturn);
+      CGM.getSanitizerMetadata()->markCallsiteAsNoReturn(CS.getInstruction());
     }
 
     EmitUnreachable(Loc);
Index: clang/lib/CodeGen/SanitizerMetadata.h
===================================================================
--- clang/lib/CodeGen/SanitizerMetadata.h
+++ clang/lib/CodeGen/SanitizerMetadata.h
@@ -44,7 +44,9 @@
                           bool IsBlacklisted = false);
   void disableSanitizerForGlobal(llvm::GlobalVariable *GV);
   void disableSanitizerForInstruction(llvm::Instruction *I);
+  void markCallsiteAsNoReturn(llvm::Instruction *I);
 private:
+  void annotate(llvm::Instruction *I, StringRef Kind);
   llvm::MDNode *getLocationMetadata(SourceLocation Loc);
 };
 }  // end namespace CodeGen
Index: clang/lib/CodeGen/SanitizerMetadata.cpp
===================================================================
--- clang/lib/CodeGen/SanitizerMetadata.cpp
+++ clang/lib/CodeGen/SanitizerMetadata.cpp
@@ -14,6 +14,7 @@
 #include "CodeGenModule.h"
 #include "clang/AST/Type.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/IR/CallSite.h"
 #include "llvm/IR/Constants.h"
 
 using namespace clang;
@@ -87,7 +88,16 @@
 }
 
 void SanitizerMetadata::disableSanitizerForInstruction(llvm::Instruction *I) {
-  I->setMetadata(CGM.getModule().getMDKindID("nosanitize"),
+  annotate(I, "nosanitize");
+}
+
+void SanitizerMetadata::markCallsiteAsNoReturn(llvm::Instruction *I) {
+  assert(llvm::CallSite(I) && "Only callsites can be marked noreturn");
+  annotate(I, "sanitizer_noreturn");
+}
+
+void SanitizerMetadata::annotate(llvm::Instruction *I, StringRef Kind) {
+  I->setMetadata(CGM.getModule().getMDKindID(Kind),
                  llvm::MDNode::get(CGM.getLLVMContext(), None));
 }
 
Index: clang/test/CodeGenCXX/ubsan-unreachable.cpp
===================================================================
--- clang/test/CodeGenCXX/ubsan-unreachable.cpp
+++ clang/test/CodeGenCXX/ubsan-unreachable.cpp
@@ -2,38 +2,35 @@
 
 extern void __attribute__((noreturn)) abort();
 
-// CHECK-LABEL: define void @_Z14calls_noreturnv
+// CHECK-LABEL: define void @_Z14calls_noreturnv()
 void calls_noreturn() {
+  // CHECK: call void @_Z5abortv(), !sanitizer_noreturn
   abort();
 
-  // Check that there are no attributes on the call site.
-  // CHECK-NOT: call void @_Z5abortv{{.*}}#
-
   // CHECK: __ubsan_handle_builtin_unreachable
   // CHECK: unreachable
 }
 
 struct A {
-  // CHECK: declare void @_Z5abortv{{.*}} [[ABORT_ATTR:#[0-9]+]]
+  // CHECK: declare void @_Z5abortv() [[EXTERN_FN_ATTR:#[0-9]+]]
 
   // CHECK-LABEL: define linkonce_odr void @_ZN1A5call1Ev
   void call1() {
-    // CHECK-NOT: call void @_ZN1A16does_not_return2Ev{{.*}}#
+    // CHECK: call void @_ZN1A16does_not_return2Ev({{.*}}), !sanitizer_noreturn
     does_not_return2();
 
     // CHECK: __ubsan_handle_builtin_unreachable
     // CHECK: unreachable
   }
 
-  // Test static members.
+  // Test static members. Checks are below after `struct A` scope ends.
   static void __attribute__((noreturn)) does_not_return1() {
-    // CHECK-NOT: call void @_Z5abortv{{.*}}#
     abort();
   }
 
   // CHECK-LABEL: define linkonce_odr void @_ZN1A5call2Ev
   void call2() {
-    // CHECK-NOT: call void @_ZN1A16does_not_return1Ev{{.*}}#
+    // CHECK: call void @_ZN1A16does_not_return1Ev(), !sanitizer_noreturn
     does_not_return1();
 
     // CHECK: __ubsan_handle_builtin_unreachable
@@ -48,16 +45,16 @@
     MemFn MF = &A::does_not_return2;
     (this->*MF)();
 
-    // CHECK-NOT: call void %{{.*}}#
+    // CHECK: call void %{{[0-9]+\(.*}}), !sanitizer_noreturn
     // CHECK: __ubsan_handle_builtin_unreachable
     // CHECK: unreachable
   }
 
   // Test regular members.
   // CHECK-LABEL: define linkonce_odr void @_ZN1A16does_not_return2Ev({{.*}})
-  // CHECK-SAME: [[DOES_NOT_RETURN_ATTR:#[0-9]+]]
+  // CHECK-SAME: [[USER_FN_ATTR:#[0-9]+]]
   void __attribute__((noreturn)) does_not_return2() {
-    // CHECK-NOT: call void @_Z5abortv(){{.*}}#
+    // CHECK: call void @_Z5abortv(), !sanitizer_noreturn
     abort();
 
     // CHECK: call void @__ubsan_handle_builtin_unreachable
@@ -68,7 +65,9 @@
   }
 };
 
-// CHECK: define linkonce_odr void @_ZN1A16does_not_return1Ev() [[DOES_NOT_RETURN_ATTR]]
+// CHECK-LABEL: define linkonce_odr void @_ZN1A16does_not_return1Ev()
+// CHECK-SAME: [[USER_FN_ATTR]]
+// CHECK: call void @_Z5abortv(), !sanitizer_noreturn
 
 void force_irgen() {
   A a;
@@ -77,5 +76,6 @@
   a.call3();
 }
 
-// CHECK-NOT: [[ABORT_ATTR]] = {{[^}]+}}noreturn
-// CHECK-NOT: [[DOES_NOT_RETURN_ATTR]] = {{[^}]+}}noreturn
+// CHECK-LABEL: attributes
+// CHECK: [[USER_FN_ATTR]] = { {{.*[^noreturn].*}}}
+// CHECK: [[EXTERN_FN_ATTR]] = { {{.*[^noreturn].*}} 
Index: compiler-rt/test/asan/TestCases/ubsan_noreturn_compatibility.c
===================================================================
--- /dev/null
+++ compiler-rt/test/asan/TestCases/ubsan_noreturn_compatibility.c
@@ -0,0 +1,14 @@
+// Test compatibility with -fsanitize=unreachable in the presence of noreturn
+// functions
+// RUN: %clang_asan -O2 -fsanitize=unreachable %s -emit-llvm -S -o - | FileCheck %s
+
+#include <stdlib.h>
+
+// CHECK-LABEL: define void @foo()
+void foo() {
+// CHECK:       call void @__asan_handle_no_return
+// CHECK-NEXT:  call void @exit
+  exit(0);
+// CHECK-NEXT:  call void @__ubsan_handle_builtin_unreachable
+// CHECK-NEXT:  unreachable
+}
Index: llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
===================================================================
--- llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -2569,7 +2569,11 @@
         if (CS) {
           // A call inside BB.
           TempsToInstrument.clear();
-          if (CS.doesNotReturn()) NoReturnCalls.push_back(CS.getInstruction());
+          bool NoReturn =
+              CS.doesNotReturn() || CS->getMetadata("sanitizer_noreturn");
+          bool NoSanitize = CS->getMetadata("nosanitize");
+          if (NoReturn && !NoSanitize)
+            NoReturnCalls.push_back(CS.getInstruction());
         }
         if (CallInst *CI = dyn_cast<CallInst>(&Inst))
           maybeMarkSanitizerLibraryCallNoBuiltin(CI, TLI);
Index: llvm/test/Instrumentation/AddressSanitizer/instrument-no-return.ll
===================================================================
--- llvm/test/Instrumentation/AddressSanitizer/instrument-no-return.ll
+++ llvm/test/Instrumentation/AddressSanitizer/instrument-no-return.ll
@@ -1,37 +1,58 @@
-; RUN: opt < %s -asan -asan-module -S | FileCheck %s
+; RUN: opt < %s -asan -S | FileCheck %s
 ; AddressSanitizer must insert __asan_handle_no_return
 ; before every noreturn call or invoke.
 
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
 target triple = "x86_64-unknown-linux-gnu"
 
-declare void @MyNoReturnFunc(i32) noreturn
+declare void @NormalFunc()
+declare void @NoReturnFunc() noreturn
 
-define i32 @Call1(i8* nocapture %arg) uwtable sanitize_address {
-entry:
-  call void @MyNoReturnFunc(i32 1) noreturn  ; The call insn has noreturn attr.
-; CHECK:        @Call1
+; Instrument noreturn callsites (regardless of function)
+define i32 @Call1(i8* nocapture %arg) sanitize_address {
+  call void @NormalFunc() noreturn  ; The call insn has noreturn attr.
+  unreachable
+}
+; CHECK-LABEL:  @Call1
 ; CHECK:        call void @__asan_handle_no_return
-; CHECK-NEXT:   call void @MyNoReturnFunc
-; CHECK-NEXT: unreachable
+; CHECK-NEXT:   call void @NormalFunc
+; CHECK-NEXT:   unreachable
+
+; Instrument calls to noreturn functions (regardless of callsite)
+define i32 @Call2(i8* nocapture %arg) sanitize_address {
+  call void @NoReturnFunc()  ; No noreturn attribure on the call.
   unreachable
 }
+; CHECK-LABEL:  @Call2
+; CHECK:        call void @__asan_handle_no_return
+; CHECK-NEXT:   call void @NoReturnFunc
+; CHECK-NEXT:   unreachable
 
-define i32 @Call2(i8* nocapture %arg) uwtable sanitize_address {
-entry:
-  call void @MyNoReturnFunc(i32 1)  ; No noreturn attribure on the call.
-; CHECK:        @Call2
+; Also instrument sanitizer_noreturn callsites
+define i32 @Call3(i8* nocapture %arg) sanitize_address {
+  call void @NormalFunc(), !sanitizer_noreturn !{}
+  unreachable
+}
+; CHECK-LABEL:  @Call3
 ; CHECK:        call void @__asan_handle_no_return
-; CHECK-NEXT:   call void @MyNoReturnFunc
-; CHECK-NEXT: unreachable
+; CHECK-NEXT:   call void @NormalFunc
+; CHECK-NEXT:   unreachable
+
+; Do NOT instrument callsites marked with !nosanitize
+define i32 @Call4(i8* nocapture %arg) sanitize_address {
+  call void @NoReturnFunc() noreturn, !sanitizer_noreturn !{}, !nosanitize !{}
   unreachable
 }
+; CHECK-LABEL:  @Call4
+; CHECK-NOT:    call void @__asan_handle_no_return
+; CHECK:        call void @NoReturnFunc
+; CHECK-NEXT:   unreachable
 
 declare i32 @__gxx_personality_v0(...)
 
-define i64 @Invoke1(i8** %esc) nounwind uwtable ssp sanitize_address personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
+define i64 @Invoke1(i8** %esc) sanitize_address personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
 entry:
-  invoke void @MyNoReturnFunc(i32 1)
+  invoke void @NoReturnFunc()
           to label %invoke.cont unwind label %lpad
 
 invoke.cont:
@@ -42,8 +63,8 @@
           filter [0 x i8*] zeroinitializer
   ret i64 1
 }
-; CHECK: @Invoke1
+; CHECK-LABEL:  @Invoke1
 ; CHECK:        call void @__asan_handle_no_return
-; CHECK-NEXT:   invoke void @MyNoReturnFunc
+; CHECK-NEXT:   invoke void @NoReturnFunc
 ; CHECK: ret i64 0
 ; CHECK: ret i64 1