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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 5; struct A {6; A();7; virtual int foo(int);8; virtual int bar(float);9; };10; 11; struct B : A {12; B();13; virtual int foo(int);14; virtual int bar(float);15; };16; 17; A::A() {}18; B::B() {}19; int A::foo(int) { return 1; }20; int A::bar(float) { return 2; }21; int B::foo(int) { return 3; }22; int B::bar(float) { return 4; }23; 24; extern "C" int test(A *p, int (A::*q)(int)) { return (p->*q)(42); }25 26; Member function pointers are tracked by the combination of their object type27; and function type, which must both be compatible. Here, the call is through a28; pointer of type "int (A::*q)(int)", so the call could be dispatched to A::foo29; or B::foo. It can't be dispatched to A::bar or B::bar as the function pointer30; does not match, so those can be removed.31 32%struct.A = type { ptr }33%struct.B = type { %struct.A }34 35; CHECK: @_ZTV1A = internal unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr null, ptr @_ZN1A3fooEi, ptr null] }36@_ZTV1A = internal unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr null, ptr @_ZN1A3fooEi, ptr @_ZN1A3barEf] }, align 8, !type !0, !type !1, !type !2, !vcall_visibility !337; CHECK: @_ZTV1B = internal unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr null, ptr @_ZN1B3fooEi, ptr null] }38@_ZTV1B = internal unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr null, ptr @_ZN1B3fooEi, ptr @_ZN1B3barEf] }, align 8, !type !0, !type !1, !type !2, !type !4, !type !5, !type !6, !vcall_visibility !339 40 41; CHECK: define internal i32 @_ZN1A3fooEi(42define internal i32 @_ZN1A3fooEi(ptr nocapture readnone %this, i32) unnamed_addr #1 align 2 {43entry:44 ret i32 145}46 47; CHECK-NOT: define internal i32 @_ZN1A3barEf(48define internal i32 @_ZN1A3barEf(ptr nocapture readnone %this, float) unnamed_addr #1 align 2 {49entry:50 ret i32 251}52 53; CHECK: define internal i32 @_ZN1B3fooEi(54define internal i32 @_ZN1B3fooEi(ptr nocapture readnone %this, i32) unnamed_addr #1 align 2 {55entry:56 ret i32 357}58 59; CHECK-NOT: define internal i32 @_ZN1B3barEf(60define internal i32 @_ZN1B3barEf(ptr nocapture readnone %this, float) unnamed_addr #1 align 2 {61entry:62 ret i32 463}64 65 66define hidden void @_ZN1AC2Ev(ptr nocapture %this) {67entry:68 store ptr getelementptr inbounds inrange(-16, 16) ({ [4 x ptr] }, ptr @_ZTV1A, i64 0, i32 0, i64 2), ptr %this, align 869 ret void70}71 72define hidden void @_ZN1BC2Ev(ptr nocapture %this) {73entry:74 store ptr getelementptr inbounds inrange(-16, 16) ({ [4 x ptr] }, ptr @_ZTV1B, i64 0, i32 0, i64 2), ptr %this, align 875 ret void76}77 78define hidden i32 @test(ptr %p, i64 %q.coerce0, i64 %q.coerce1) {79entry:80 %0 = getelementptr inbounds i8, ptr %p, i64 %q.coerce181 %1 = and i64 %q.coerce0, 182 %memptr.isvirtual = icmp eq i64 %1, 083 br i1 %memptr.isvirtual, label %memptr.nonvirtual, label %memptr.virtual84 85memptr.virtual: ; preds = %entry86 %vtable = load ptr, ptr %0, align 887 %2 = add i64 %q.coerce0, -188 %3 = getelementptr i8, ptr %vtable, i64 %2, !nosanitize !1289 %4 = tail call { ptr, i1 } @llvm.type.checked.load(ptr %3, i32 0, metadata !"_ZTSM1AFiiE.virtual"), !nosanitize !1290 %5 = extractvalue { ptr, i1 } %4, 0, !nosanitize !1291 br label %memptr.end92 93memptr.nonvirtual: ; preds = %entry94 %memptr.nonvirtualfn = inttoptr i64 %q.coerce0 to ptr95 br label %memptr.end96 97memptr.end: ; preds = %memptr.nonvirtual, %memptr.virtual98 %6 = phi ptr [ %5, %memptr.virtual ], [ %memptr.nonvirtualfn, %memptr.nonvirtual ]99 %call = tail call i32 %6(ptr %0, i32 42)100 ret i32 %call101}102 103declare { ptr, i1 } @llvm.type.checked.load(ptr, i32, metadata)104 105!llvm.module.flags = !{!7}106 107!0 = !{i64 16, !"_ZTS1A"}108!1 = !{i64 16, !"_ZTSM1AFiiE.virtual"}109!2 = !{i64 24, !"_ZTSM1AFifE.virtual"}110!3 = !{i64 2}111!4 = !{i64 16, !"_ZTS1B"}112!5 = !{i64 16, !"_ZTSM1BFiiE.virtual"}113!6 = !{i64 24, !"_ZTSM1BFifE.virtual"}114!7 = !{i32 1, !"Virtual Function Elim", i32 1}115!12 = !{}116