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1; Tests that VFE is not performed when the Virtual Function Elim metadata set2; to 0. This is the same as virtual-functions.ll otherwise.3; RUN: opt < %s -passes=globaldce -S | FileCheck %s4 5target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"6 7declare dso_local noalias nonnull ptr @_Znwm(i64)8declare { ptr, i1 } @llvm.type.checked.load(ptr, i32, metadata)9 10; %struct.A is a C++ struct with two virtual functions, A::foo and A::bar. The11; !vcall_visibility metadata is set on the vtable, so we know that all virtual12; calls through this vtable are visible and use the @llvm.type.checked.load13; intrinsic. Function test_A makes a call to A::foo, but there is no call to14; A::bar anywhere, so A::bar can be deleted, and its vtable slot replaced with15; null.16; However, with the metadata set to 0 we should not perform this VFE.17 18%struct.A = type { ptr }19 20; We should retain @_ZN1A3barEv in the vtable.21; CHECK: @_ZTV1A = internal unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr null, ptr @_ZN1A3fooEv, ptr @_ZN1A3barEv] }22@_ZTV1A = internal unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr null, ptr @_ZN1A3fooEv, ptr @_ZN1A3barEv] }, align 8, !type !0, !type !1, !type !2, !vcall_visibility !323 24; A::foo is called, so must be retained.25; CHECK: define internal i32 @_ZN1A3fooEv(26define internal i32 @_ZN1A3fooEv(ptr nocapture readnone %this) {27entry:28 ret i32 4229}30 31; A::bar is not used, so can be deleted with VFE, however, we should not be32; performing that elimination here.33; CHECK: define internal i32 @_ZN1A3barEv(34define internal i32 @_ZN1A3barEv(ptr nocapture readnone %this) {35entry:36 ret i32 133737}38 39define dso_local i32 @test_A() {40entry:41 %call = tail call ptr @_Znwm(i64 8)42 store ptr getelementptr inbounds inrange(-16, 16) ({ [4 x ptr] }, ptr @_ZTV1A, i64 0, i32 0, i64 2), ptr %call, align 843 %0 = tail call { ptr, i1 } @llvm.type.checked.load(ptr getelementptr inbounds inrange(-16, 16) ({ [4 x ptr] }, ptr @_ZTV1A, i64 0, i32 0, i64 2), i32 0, metadata !"_ZTS1A"), !nosanitize !944 %1 = extractvalue { ptr, i1 } %0, 0, !nosanitize !945 %call1 = tail call i32 %1(ptr nonnull %call)46 ret i32 %call147}48 49!llvm.module.flags = !{!4}50 51!0 = !{i64 16, !"_ZTS1A"}52!1 = !{i64 16, !"_ZTSM1AFivE.virtual"}53!2 = !{i64 24, !"_ZTSM1AFivE.virtual"}54!3 = !{i64 2}55!4 = !{i32 1, !"Virtual Function Elim", i32 0}56!9 = !{}57