; RUN: opt < %s -passes=globaldce -S | FileCheck %s target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" ; struct A { ; A(); ; virtual int foo(); ; }; ; ; struct B : A { ; B(); ; virtual int foo(); ; }; ; ; A::A() {} ; B::B() {} ; int A::foo() { return 42; } ; int B::foo() { return 1337; } ; ; extern "C" int test(A *p) { return p->foo(); } ; The virtual call in test could be dispatched to either A::foo or B::foo, so ; both must be retained. %struct.A = type { ptr } %struct.B = type { %struct.A } ; CHECK: @_ZTV1A = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr null, ptr @_ZN1A3fooEv] } @_ZTV1A = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr null, ptr @_ZN1A3fooEv] }, align 8, !type !0, !type !1, !vcall_visibility !2 ; CHECK: @_ZTV1B = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr null, ptr @_ZN1B3fooEv] } @_ZTV1B = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr null, ptr @_ZN1B3fooEv] }, align 8, !type !0, !type !1, !type !3, !type !4, !vcall_visibility !2 ; CHECK: define internal i32 @_ZN1A3fooEv( define internal i32 @_ZN1A3fooEv(ptr nocapture readnone %this) { entry: ret i32 42 } ; CHECK: define internal i32 @_ZN1B3fooEv( define internal i32 @_ZN1B3fooEv(ptr nocapture readnone %this) { entry: ret i32 1337 } define hidden void @_ZN1AC2Ev(ptr nocapture %this) { entry: store ptr getelementptr inbounds ({ [3 x ptr] }, ptr @_ZTV1A, i64 0, inrange i32 0, i64 2), ptr %this, align 8 ret void } define hidden void @_ZN1BC2Ev(ptr nocapture %this) { entry: store ptr getelementptr inbounds ({ [3 x ptr] }, ptr @_ZTV1B, i64 0, inrange i32 0, i64 2), ptr %this, align 8 ret void } define hidden i32 @test(ptr %p) { entry: %vtable1 = load ptr, ptr %p, align 8 %0 = tail call { ptr, i1 } @llvm.type.checked.load(ptr %vtable1, i32 0, metadata !"_ZTS1A"), !nosanitize !10 %1 = extractvalue { ptr, i1 } %0, 0, !nosanitize !10 %call = tail call i32 %1(ptr %p) ret i32 %call } declare { ptr, i1 } @llvm.type.checked.load(ptr, i32, metadata) #2 !llvm.module.flags = !{!5} !0 = !{i64 16, !"_ZTS1A"} !1 = !{i64 16, !"_ZTSM1AFivE.virtual"} !2 = !{i64 2} !3 = !{i64 16, !"_ZTS1B"} !4 = !{i64 16, !"_ZTSM1BFivE.virtual"} !5 = !{i32 1, !"Virtual Function Elim", i32 1} !10 = !{}