[Sanitizers] UBSan unreachable incompatible with Kernel ASan

[yln]

Summary

This is a follow up for https://reviews.llvm.org/D57278. The previous
revision should have also included Kernel ASan.

rdar://problem/40723397

[vsk]

LGTM, thanks. It might make sense to add a predicate to SanitizerSet to make it easier to check when ASan is enabled, either pre-commit or as a follow-up.

[eugenis]

LGTM

clang/lib/CodeGen/CGCall.cpp

if (SanOpts.has(SanitizerKind::Unreachable)) {
       // attributes of the called function.
       if (auto *F = CI->getCalledFunction())
         F->removeFnAttr(llvm::Attribute::NoReturn);
       CI->removeAttribute(llvm::AttributeList::FunctionIndex,
                           llvm::Attribute::NoReturn);
 
       // Avoid incompatibility with ASan which relies on the `noreturn`
       // attribute to insert handler calls.
-      if (SanOpts.has(SanitizerKind::Address)) {
+      if (SanOpts.hasOneOf(SanitizerKind::Address |
+                           SanitizerKind::KernelAddress)) {
         SanitizerScope SanScope(this);
         llvm::IRBuilder<>::InsertPointGuard IPGuard(Builder);
         Builder.SetInsertPoint(CI);
         auto *FnType = llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
         auto *Fn = CGM.CreateRuntimeFunction(FnType, "__asan_handle_no_return");
         EmitNounwindRuntimeCall(Fn);
       }
     }

clang/test/CodeGen/ubsan-asan-noreturn.c

 // Ensure compatiblity of UBSan unreachable with ASan in the presence of
 // noreturn functions.
-// RUN: %clang_cc1 -fsanitize=unreachable,address -triple x86_64-linux -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -fsanitize=unreachable,address        -triple x86_64-linux -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -fsanitize=unreachable,kernel-address -triple x86_64-linux -emit-llvm -o - %s | FileCheck %s
 
 void my_longjmp(void) __attribute__((noreturn));
 
 // CHECK-LABEL: define void @calls_noreturn()
 void calls_noreturn() {
   my_longjmp();
   // CHECK:      @__asan_handle_no_return{{.*}} !nosanitize
   // CHECK-NEXT: @my_longjmp(){{[^#]*}}

llvm/test/Instrumentation/AddressSanitizer/instrument-no-return.ll

 define i32 @Call3() sanitize_address {
   call void @NoReturnFunc() noreturn, !nosanitize !{}
   unreachable
 }
 ; CHECK-LABEL:  @Call3
 ; CHECK-NOT:    call void @__asan_handle_no_return
 ; CHECK:        call void @NoReturnFunc
 
+; Do *not* instrument functions without ASan
+define i32 @Call4() {
+  call void @NoReturnFunc() noreturn
+  unreachable
+}
+; CHECK-LABEL:  @Call4
+; CHECK-NOT:    call void @__asan_handle_no_return
+; CHECK:        call void @NoReturnFunc
+
 declare i32 @__gxx_personality_v0(...)
 
 define i64 @Invoke1() nounwind uwtable ssp sanitize_address personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
 entry:
   invoke void @NoReturnFunc()
           to label %invoke.cont unwind label %lpad
 
 invoke.cont: