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1; RUN: opt < %s -passes='globaldce' -S | FileCheck %s2 3target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"4 5declare { ptr, i1 } @llvm.type.checked.load(ptr, i32, metadata)6 7; A vtable with "relative pointers", slots don't contain pointers to implementations, but instead have an i32 offset from the vtable itself to the implementation.8@vtable = internal unnamed_addr constant { [4 x i32] } { [4 x i32] [9 i32 42,10 i32 1337,11 i32 trunc (i64 sub (i64 ptrtoint (ptr @vfunc1_live to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [4 x i32] }, ptr @vtable, i32 0, i32 0, i32 2) to i64)) to i32),12 i32 trunc (i64 sub (i64 ptrtoint (ptr @vfunc2_dead to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [4 x i32] }, ptr @vtable, i32 0, i32 0, i32 2) to i64)) to i32)13]}, align 8, !type !0, !type !1, !vcall_visibility !{i64 2}14!0 = !{i64 8, !"vfunc1.type"}15!1 = !{i64 12, !"vfunc2.type"}16 17; CHECK: @vtable = internal unnamed_addr constant { [4 x i32] } { [4 x i32] [18; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @vfunc1_live to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [4 x i32] }, ptr @vtable, i32 0, i32 0, i32 2) to i64)) to i32),19; CHECK-SAME: i32 020; CHECK-SAME: ] }, align 8, !type !0, !type !1, !vcall_visibility !221 22@vtable2 = internal unnamed_addr constant { [4 x i32] } { [4 x i32] [23 i32 42,24 i32 1337,25 i32 trunc (i64 sub (i64 ptrtoint (ptr dso_local_equivalent @vfunc3_live_extern to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [4 x i32] }, ptr @vtable2, i32 0, i32 0, i32 2) to i64)) to i32),26 i32 trunc (i64 sub (i64 ptrtoint (ptr dso_local_equivalent @vfunc4_dead_extern to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [4 x i32] }, ptr @vtable2, i32 0, i32 0, i32 2) to i64)) to i32)27]}, align 4, !type !3, !type !4, !vcall_visibility !{i64 2}28!3 = !{i64 8, !"vfunc3.type"}29!4 = !{i64 12, !"vfunc4.type"}30 31; CHECK: @vtable2 = internal unnamed_addr constant { [4 x i32] } { [4 x i32] [32; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr dso_local_equivalent @vfunc3_live_extern to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [4 x i32] }, ptr @vtable2, i32 0, i32 0, i32 2) to i64)) to i32),33; CHECK-SAME: i32 034; CHECK-SAME: ] }, align 4, !type !3, !type !4, !vcall_visibility !235 36; (1) vfunc1_live is referenced from @main, stays alive37define internal void @vfunc1_live() {38 ; CHECK: define internal void @vfunc1_live(39 ret void40}41 42; (2) vfunc2_dead is never referenced, gets removed and vtable slot is null'd43define internal void @vfunc2_dead() {44 ; CHECK-NOT: define internal void @vfunc2_dead(45 ret void46}47 48; (3) vfunc3_live_extern is referenced from @main, stays alive49; CHECK: declare void @vfunc3_live_extern50declare void @vfunc3_live_extern()51 52; (4) vfunc4_dead_extern is never referenced, gets removed and vtable slot is null'd53; CHECK-NOT: declare void @vfunc4_dead_extern54declare void @vfunc4_dead_extern()55 56define void @main() {57 %1 = ptrtoint ptr @vtable to i64 ; to keep @vtable alive58 %2 = tail call { ptr, i1 } @llvm.type.checked.load(ptr null, i32 0, metadata !"vfunc1.type")59 %3 = ptrtoint ptr @vtable2 to i64 ; to keep @vtable2 alive60 %4 = tail call { ptr, i1 } @llvm.type.checked.load(ptr null, i32 0, metadata !"vfunc3.type")61 ret void62}63 64!999 = !{i32 1, !"Virtual Function Elim", i32 1}65!llvm.module.flags = !{!999}66