diff --git a/llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp b/llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp --- a/llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp +++ b/llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp @@ -2311,6 +2311,13 @@ DenseMap> NameByGUID; for (const auto &P : ExportSummary.typeIdCompatibleVtableMap()) { NameByGUID[GlobalValue::getGUID(P.first)].push_back(P.first); + // Create the type id summary resolution regardlness of whether we can + // devirtualize, so that lower type tests knows the type id is used on + // a global and not Unsat. We do this here rather than in the loop over the + // CallSlots, since that handling will only see type tests that directly + // feed assumes, and we would miss any that aren't currently handled by WPD + // (such as type tests that feed assumes via phis). + ExportSummary.getOrInsertTypeIdSummary(P.first); } // Collect information from summary about which calls to try to devirtualize. @@ -2358,12 +2365,11 @@ std::vector TargetsForSlot; auto TidSummary = ExportSummary.getTypeIdCompatibleVtableSummary(S.first.TypeID); assert(TidSummary); - // Create the type id summary resolution regardlness of whether we can - // devirtualize, so that lower type tests knows the type id is used on - // a global and not Unsat. + // The type id summary would have been created while building the NameByGUID + // map earlier. WholeProgramDevirtResolution *Res = - &ExportSummary.getOrInsertTypeIdSummary(S.first.TypeID) - .WPDRes[S.first.ByteOffset]; + &ExportSummary.getTypeIdSummary(S.first.TypeID) + ->WPDRes[S.first.ByteOffset]; if (tryFindVirtualCallTargets(TargetsForSlot, *TidSummary, S.first.ByteOffset)) { diff --git a/llvm/test/ThinLTO/X86/lower_type_test_phi.ll b/llvm/test/ThinLTO/X86/lower_type_test_phi.ll new file mode 100644 --- /dev/null +++ b/llvm/test/ThinLTO/X86/lower_type_test_phi.ll @@ -0,0 +1,163 @@ +; Test to ensure that type tests feeding assumes via a phi are lowered +; correctly after ThinLTO index-only WPD, which needs to set up the necessary +; type id summaries. + +; RUN: rm -rf %t && split-file %s %t && cd %t + +; RUN: opt -thinlto-bc y.ll -o y.bc +; RUN: opt -thinlto-bc z.ll -o z.bc + +; RUN: llvm-lto2 run y.bc z.bc -o out \ +; RUN: -r y.bc,main,plx \ +; RUN: -r y.bc,_Z2b1v, \ +; RUN: -r y.bc,_Z2b2v, \ +; RUN: -r z.bc,_Z2b1v,pl \ +; RUN: -r z.bc,_Znwm, \ +; RUN: -r z.bc,_Z2b2v,pl \ +; RUN: -r z.bc,_ZN2D11fEv,pl \ +; RUN: -r z.bc,_ZN1B1fEv,pl \ +; RUN: -r z.bc,_ZN2D21fEv,pl \ +; RUN: -r z.bc,_ZTV2D1,pl \ +; RUN: -r z.bc,_ZTV1B,pl \ +; RUN: -r z.bc,_ZTV2D2,pl \ +; RUN: -print-after=lowertypetests -filter-print-funcs=main 2>&1 | FileCheck %s + +; The first LTT should leave the type tests as is (instead of lowering +; them to false incorrectly). +; CHECK: *** IR Dump After LowerTypeTestsPass on [module] *** +; CHECK: 4: +; CHECK: %7 = tail call i1 @llvm.type.test(ptr %6, metadata !"_ZTS2D1") +; CHECK: br label %12 +; CHECK: 8: +; CHECK: %11 = tail call i1 @llvm.type.test(ptr %10, metadata !"_ZTS2D2") +; CHECK: br label %12 +; CHECK: 12: +; CHECK: %13 = phi i1 [ %11, %8 ], [ %7, %4 ] + +; The second LTT should lower them to true. +; CHECK: *** IR Dump After LowerTypeTestsPass on [module] *** +; CHECK-NOT: @llvm.type.test +; CHECK: 10: +; CHECK: %11 = phi i1 [ true, %7 ], [ true, %4 ] + + +;--- y.ll +; ModuleID = 'y.cc' +source_filename = "y.cc" +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define i32 @main(i32 %argc, ptr %argv) { +entry: + %tobool.not = icmp eq i32 %argc, 0 + br i1 %tobool.not, label %if.else, label %if.then + +if.then: + %call = tail call ptr @_Z2b1v() + %vtable = load ptr, ptr %call, align 8 + %0 = tail call i1 @llvm.type.test(ptr %vtable, metadata !"_ZTS2D1") + br label %if.end + +if.else: + %call1 = tail call ptr @_Z2b2v() + %vtable2 = load ptr, ptr %call1, align 8 + %1 = tail call i1 @llvm.type.test(ptr %vtable2, metadata !"_ZTS2D2") + br label %if.end + +if.end: + %.sink = phi i1 [ %1, %if.else ], [ %0, %if.then ] + %vtable2.sink = phi ptr [ %vtable2, %if.else ], [ %vtable, %if.then ] + %call1.sink = phi ptr [ %call1, %if.else ], [ %call, %if.then ] + tail call void @llvm.assume(i1 %.sink) + %2 = load ptr, ptr %vtable2.sink, align 8 + tail call void %2(ptr align 8 %call1.sink) + ret i32 0 +} + +declare ptr @_Z2b1v() + +declare i1 @llvm.type.test(ptr, metadata) + +declare void @llvm.assume(i1) + +declare ptr @_Z2b2v() + +!llvm.module.flags = !{!0, !1, !2, !3, !4} +!llvm.ident = !{!5} + +!0 = !{i32 1, !"wchar_size", i32 4} +!1 = !{i32 1, !"Virtual Function Elim", i32 0} +!2 = !{i32 7, !"PIC Level", i32 2} +!3 = !{i32 7, !"PIE Level", i32 2} +!4 = !{i32 7, !"uwtable", i32 2} +!5 = !{!"clang version 15.0.0 (git@github.com:llvm/llvm-project.git e6f39e3f31ba88f2084a5d987f9a827aff4e17b1)"} + +;--- z.ll +; ModuleID = 'z.cc' +source_filename = "z.cc" +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +$_ZN2D11fEv = comdat any + +$_ZN1B1fEv = comdat any + +$_ZN2D21fEv = comdat any + +$_ZTV2D1 = comdat any + +$_ZTV1B = comdat any + +$_ZTV2D2 = comdat any + +@_ZTV2D1 = linkonce_odr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr null, ptr @_ZN2D11fEv] }, comdat, align 8, !type !0, !type !1, !type !2, !type !3, !vcall_visibility !4 +@_ZTV1B = linkonce_odr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr null, ptr @_ZN1B1fEv] }, comdat, align 8, !type !0, !type !1, !vcall_visibility !4 +@_ZTV2D2 = linkonce_odr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr null, ptr @_ZN2D21fEv] }, comdat, align 8, !type !0, !type !1, !type !5, !type !6, !vcall_visibility !4 + +define ptr @_Z2b1v() { +entry: + %call = tail call ptr @_Znwm(i64 8) + store ptr getelementptr inbounds ({ [3 x ptr] }, ptr @_ZTV2D1, i64 0, inrange i32 0, i64 2), ptr %call, align 8 + ret ptr %call +} + +declare ptr @_Znwm(i64) + +define ptr @_Z2b2v() { +entry: + %call = tail call ptr @_Znwm(i64 8) + store ptr getelementptr inbounds ({ [3 x ptr] }, ptr @_ZTV2D2, i64 0, inrange i32 0, i64 2), ptr %call, align 8 + ret ptr %call +} + +define linkonce_odr void @_ZN2D11fEv(ptr %this) comdat align 2 { +entry: + ret void +} + +define linkonce_odr void @_ZN1B1fEv(ptr %this) comdat align 2 { +entry: + ret void +} + +define linkonce_odr void @_ZN2D21fEv(ptr %this) comdat align 2 { +entry: + ret void +} + +!llvm.module.flags = !{!7, !8, !9, !10, !11} +!llvm.ident = !{!12} + +!0 = !{i64 16, !"_ZTS1B"} +!1 = !{i64 16, !"_ZTSM1BFvvE.virtual"} +!2 = !{i64 16, !"_ZTS2D1"} +!3 = !{i64 16, !"_ZTSM2D1FvvE.virtual"} +!4 = !{i64 1} +!5 = !{i64 16, !"_ZTS2D2"} +!6 = !{i64 16, !"_ZTSM2D2FvvE.virtual"} +!7 = !{i32 1, !"wchar_size", i32 4} +!8 = !{i32 1, !"Virtual Function Elim", i32 0} +!9 = !{i32 7, !"PIC Level", i32 2} +!10 = !{i32 7, !"PIE Level", i32 2} +!11 = !{i32 7, !"uwtable", i32 2} +!12 = !{!"clang version 15.0.0 (git@github.com:llvm/llvm-project.git e6f39e3f31ba88f2084a5d987f9a827aff4e17b1)"}