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; RUN: opt -S -passes=globaldce < %s | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
declare { ptr, i1 } @llvm.type.checked.load(ptr, i32, metadata)
; A vtable that contains a non-nfunc entry, @regular_non_virtual_funcA, but
; without a range specific in !vcall_visibility, which means *all* function
; pointers are eligible for VFE, so GlobalDCE will treat the
; @regular_non_virtual_funcA slot as eligible for VFE, and remove it.
@vtableA = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [
ptr @vfunc1_live,
ptr @vfunc2_dead,
ptr @regular_non_virtual_funcA
]}, align 8, !type !{i64 0, !"vfunc1.type"}, !type !{i64 8, !"vfunc2.type"}, !vcall_visibility !{i64 2}
; CHECK: @vtableA = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [
; CHECK-SAME: ptr @vfunc1_live,
; CHECK-SAME: ptr null,
; CHECK-SAME: ptr null
; CHECK-SAME: ] }, align 8
; A vtable that contains a non-nfunc entry, @regular_non_virtual_funcB, with a
; range of [0,16) which means only the first two entries are eligible for VFE.
; GlobalDCE should keep @regular_non_virtual_funcB in the vtable.
@vtableB = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [
ptr @vfunc1_live,
ptr @vfunc2_dead,
ptr @regular_non_virtual_funcB
]}, align 8, !type !{i64 0, !"vfunc1.type"}, !type !{i64 8, !"vfunc2.type"}, !vcall_visibility !{i64 2, i64 0, i64 16}
; CHECK: @vtableB = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [
; CHECK-SAME: ptr @vfunc1_live,
; CHECK-SAME: ptr null,
; CHECK-SAME: ptr @regular_non_virtual_funcB
; CHECK-SAME: ] }, align 8
; A vtable that contains a non-nfunc entry, @regular_non_virtual_funcB, with a
; range of [0,16) which means only the first two entries are eligible for VFE.
; GlobalDCE should keep @regular_non_virtual_funcB in the vtable.
@vtableC = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [
ptr @regular_non_virtual_funcC,
ptr @vfunc1_live,
ptr @vfunc2_dead
]}, align 8, !type !{i64 8, !"vfunc1.type"}, !type !{i64 16, !"vfunc2.type"}, !vcall_visibility !{i64 2, i64 8, i64 24}
; CHECK: @vtableC = internal unnamed_addr constant { [3 x ptr] } { [3 x ptr] [
; CHECK-SAME: ptr @regular_non_virtual_funcC,
; CHECK-SAME: ptr @vfunc1_live,
; CHECK-SAME: ptr null
; CHECK-SAME: ] }, align 8
; A vtable with "relative pointers"
@vtableD = internal unnamed_addr constant { i32, i32, ptr } {
i32 trunc (i64 sub (i64 ptrtoint (ptr @vfunc1_live to i64), i64 ptrtoint (ptr @vtableD to i64)) to i32),
i32 trunc (i64 sub (i64 ptrtoint (ptr @vfunc2_dead to i64), i64 ptrtoint (ptr @vtableD to i64)) to i32),
ptr @regular_non_virtual_funcD
}, align 8, !type !{i64 0, !"vfunc1.type"}, !type !{i64 4, !"vfunc2.type"}, !vcall_visibility !{i64 2, i64 0, i64 8}
; CHECK: @vtableD = internal unnamed_addr constant { i32, i32, ptr } {
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @vfunc1_live to i64), i64 ptrtoint (ptr @vtableD to i64)) to i32),
; CHECK-SAME: i32 0,
; CHECK-SAME: ptr @regular_non_virtual_funcD
; CHECK-SAME: }, align 8
; (1) vfunc1_live is referenced from @main, stays alive
define internal void @vfunc1_live() {
; CHECK: define internal void @vfunc1_live(
ret void
}
; (2) vfunc2_dead is never referenced, gets removed and vtable slot is null'd
define internal void @vfunc2_dead() {
; CHECK-NOT: define internal void @vfunc2_dead(
ret void
}
; (3) not using a range in !vcall_visibility, global gets removed
define internal void @regular_non_virtual_funcA() {
; CHECK-NOT: define internal void @regular_non_virtual_funcA(
ret void
}
; (4) using a range in !vcall_visibility, pointer is outside of range, so should
; stay alive
define internal void @regular_non_virtual_funcB() {
; CHECK: define internal void @regular_non_virtual_funcB(
ret void
}
; (5) using a range in !vcall_visibility, pointer is outside of range, so should
; stay alive
define internal void @regular_non_virtual_funcC() {
; CHECK: define internal void @regular_non_virtual_funcC(
ret void
}
; (6) using a range in !vcall_visibility, pointer is outside of range, so should
; stay alive
define internal void @regular_non_virtual_funcD() {
; CHECK: define internal void @regular_non_virtual_funcD(
ret void
}
define void @main() {
%1 = ptrtoint { [3 x ptr] }* @vtableA to i64 ; to keep @vtableA alive
%2 = ptrtoint { [3 x ptr] }* @vtableB to i64 ; to keep @vtableB alive
%3 = ptrtoint { [3 x ptr] }* @vtableC to i64 ; to keep @vtableC alive
%4 = ptrtoint { i32, i32, ptr }* @vtableD to i64 ; to keep @vtableD alive
%5 = tail call { ptr, i1 } @llvm.type.checked.load(ptr null, i32 0, metadata !"vfunc1.type")
ret void
}
!999 = !{i32 1, !"Virtual Function Elim", i32 1}
!llvm.module.flags = !{!999}
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