1; RUN: opt < %s -passes='globaldce' -S | FileCheck %s 2 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 0 20; CHECK-SAME: ] }, align 8, !type !0, !type !1, !vcall_visibility !2 21 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 0 34; CHECK-SAME: ] }, align 4, !type !3, !type !4, !vcall_visibility !2 35 36; (1) vfunc1_live is referenced from @main, stays alive 37define internal void @vfunc1_live() { 38 ; CHECK: define internal void @vfunc1_live( 39 ret void 40} 41 42; (2) vfunc2_dead is never referenced, gets removed and vtable slot is null'd 43define internal void @vfunc2_dead() { 44 ; CHECK-NOT: define internal void @vfunc2_dead( 45 ret void 46} 47 48; (3) vfunc3_live_extern is referenced from @main, stays alive 49; CHECK: declare void @vfunc3_live_extern 50declare void @vfunc3_live_extern() 51 52; (4) vfunc4_dead_extern is never referenced, gets removed and vtable slot is null'd 53; CHECK-NOT: declare void @vfunc4_dead_extern 54declare void @vfunc4_dead_extern() 55 56define void @main() { 57 %1 = ptrtoint ptr @vtable to i64 ; to keep @vtable alive 58 %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 alive 60 %4 = tail call { ptr, i1 } @llvm.type.checked.load(ptr null, i32 0, metadata !"vfunc3.type") 61 ret void 62} 63 64!999 = !{i32 1, !"Virtual Function Elim", i32 1} 65!llvm.module.flags = !{!999} 66