1 files changed, 47 insertions, 0 deletions
diff --git a/llvm/test/Transforms/GlobalDCE/vtable-rtti.ll b/llvm/test/Transforms/GlobalDCE/vtable-rtti.ll
new file mode 100644
index 00000000000..dd611934055
--- /dev/null
+++ b/llvm/test/Transforms/GlobalDCE/vtable-rtti.ll
@@ -0,0 +1,47 @@
+; RUN: opt < %s -globaldce -S | FileCheck %s
+
+; We currently only use llvm.type.checked.load for virtual function pointers,
+; not any other part of the vtable, so we can't remove the RTTI pointer even if
+; it's never going to be loaded from.
+
+target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
+
+%struct.A = type { i32 (...)** }
+
+; CHECK: @_ZTV1A = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* bitcast ({ i8*, i8* }* @_ZTI1A to i8*), i8* null] }, align 8, !type !0, !type !1, !vcall_visibility !2
+
+@_ZTV1A = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* bitcast ({ i8*, i8* }* @_ZTI1A to i8*), i8* bitcast (void (%struct.A*)* @_ZN1A3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !2
+@_ZTS1A = hidden constant [3 x i8] c"1A\00", align 1
+@_ZTI1A = hidden constant { i8*, i8* } { i8* bitcast (i8** getelementptr inbounds (i8*, i8** @_ZTVN10__cxxabiv117__class_type_infoE, i64 2) to i8*), i8* getelementptr inbounds ([3 x i8], [3 x i8]* @_ZTS1A, i32 0, i32 0) }, align 8
+
+define internal void @_ZN1AC2Ev(%struct.A* %this) {
+entry:
+  %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
+  store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
+  ret void
+}
+
+; CHECK-NOT: define {{.*}} @_ZN1A3fooEv(
+define internal void @_ZN1A3fooEv(%struct.A* nocapture %this) {
+entry:
+  ret void
+}
+
+define dso_local i8* @_Z6make_Av() {
+entry:
+  %call = tail call i8* @_Znwm(i64 8)
+  %0 = bitcast i8* %call to %struct.A*
+  tail call void @_ZN1AC2Ev(%struct.A* %0)
+  ret i8* %call
+}
+
+
+declare dso_local noalias nonnull i8* @_Znwm(i64)
+@_ZTVN10__cxxabiv117__class_type_infoE = external dso_local global i8*
+
+!llvm.module.flags = !{!3}
+
+!0 = !{i64 16, !"_ZTS1A"}
+!1 = !{i64 16, !"_ZTSM1AFvvE.virtual"}
+!2 = !{i64 2} ; translation-unit vcall visibility
+!3 = !{i32 1, !"LTOPostLink", i32 1}