From a7d69b86de58380831eebb9d905bf43cb0120684 Mon Sep 17 00:00:00 2001 From: Teresa Johnson Date: Thu, 19 Jul 2018 22:25:56 +0000 Subject: [PATCH] [ThinLTO] Only emit referenced type id records in index files Summary: Currently all type ids are emitted into the index file when it is written. For distributed ThinLTO, that meant that all type ids were being duplicated into every single distributed index file, regardless of whether they were referenced, leading to huge amounts of unnecessary duplication and size bloat. Keep track of the type id GUIDs actually referenced by the GV summary records being emitted, and only emit those type IDs. Add a new test, and fix test/Assembler/thinlto-summary.ll so that all type ids are referenced to prevent deletion in that test. Reviewers: pcc Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, vitalybuka, llvm-commits Differential Revision: https://reviews.llvm.org/D49565 llvm-svn: 337503 --- lib/Bitcode/Writer/BitcodeWriter.cpp | 24 +++++++-- test/Assembler/thinlto-summary.ll | 4 +- test/ThinLTO/X86/Inputs/cfi-distributed.ll | 28 ++++++++++ test/ThinLTO/X86/cfi-distributed.ll | 60 ++++++++++++++++++++++ 4 files changed, 109 insertions(+), 7 deletions(-) create mode 100644 test/ThinLTO/X86/Inputs/cfi-distributed.ll create mode 100644 test/ThinLTO/X86/cfi-distributed.ll diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp index 9072be68372..be75df0820d 100644 --- a/lib/Bitcode/Writer/BitcodeWriter.cpp +++ b/lib/Bitcode/Writer/BitcodeWriter.cpp @@ -3353,10 +3353,14 @@ void IndexBitcodeWriter::writeModStrings() { /// Write the function type metadata related records that need to appear before /// a function summary entry (whether per-module or combined). -static void writeFunctionTypeMetadataRecords(BitstreamWriter &Stream, - FunctionSummary *FS) { - if (!FS->type_tests().empty()) +static void writeFunctionTypeMetadataRecords( + BitstreamWriter &Stream, FunctionSummary *FS, + std::set &ReferencedTypeIds) { + if (!FS->type_tests().empty()) { Stream.EmitRecord(bitc::FS_TYPE_TESTS, FS->type_tests()); + for (auto &TT : FS->type_tests()) + ReferencedTypeIds.insert(TT); + } SmallVector Record; @@ -3368,6 +3372,7 @@ static void writeFunctionTypeMetadataRecords(BitstreamWriter &Stream, for (auto &VF : VFs) { Record.push_back(VF.GUID); Record.push_back(VF.Offset); + ReferencedTypeIds.insert(VF.GUID); } Stream.EmitRecord(Ty, Record); }; @@ -3382,6 +3387,7 @@ static void writeFunctionTypeMetadataRecords(BitstreamWriter &Stream, for (auto &VC : VCs) { Record.clear(); Record.push_back(VC.VFunc.GUID); + ReferencedTypeIds.insert(VC.VFunc.GUID); Record.push_back(VC.VFunc.Offset); Record.insert(Record.end(), VC.Args.begin(), VC.Args.end()); Stream.EmitRecord(Ty, Record); @@ -3447,7 +3453,8 @@ void ModuleBitcodeWriterBase::writePerModuleFunctionSummaryRecord( NameVals.push_back(ValueID); FunctionSummary *FS = cast(Summary); - writeFunctionTypeMetadataRecords(Stream, FS); + std::set ReferencedTypeIds; + writeFunctionTypeMetadataRecords(Stream, FS, ReferencedTypeIds); NameVals.push_back(getEncodedGVSummaryFlags(FS->flags())); NameVals.push_back(FS->instCount()); @@ -3702,6 +3709,10 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() { SmallVector NameVals; + // Set that will be populated during call to writeFunctionTypeMetadataRecords + // with the type ids referenced by this index file. + std::set ReferencedTypeIds; + // For local linkage, we also emit the original name separately // immediately after the record. auto MaybeEmitOriginalName = [&](GlobalValueSummary &S) { @@ -3753,7 +3764,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() { } auto *FS = cast(S); - writeFunctionTypeMetadataRecords(Stream, FS); + writeFunctionTypeMetadataRecords(Stream, FS, ReferencedTypeIds); NameVals.push_back(*ValueId); NameVals.push_back(Index.getModuleId(FS->modulePath())); @@ -3862,6 +3873,9 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() { if (!Index.typeIds().empty()) { for (auto &S : Index.typeIds()) { + // Skip if not referenced in any GV summary within this index file. + if (!ReferencedTypeIds.count(GlobalValue::getGUID(S.first))) + continue; writeTypeIdSummaryRecord(NameVals, StrtabBuilder, S.first, S.second); Stream.EmitRecord(bitc::FS_TYPE_ID, NameVals); NameVals.clear(); diff --git a/test/Assembler/thinlto-summary.ll b/test/Assembler/thinlto-summary.ll index 66a5bef015e..6722fb1a8b7 100644 --- a/test/Assembler/thinlto-summary.ll +++ b/test/Assembler/thinlto-summary.ll @@ -50,7 +50,7 @@ ^20 = gv: (guid: 19, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 8, typeIdInfo: (typeTestAssumeVCalls: (vFuncId: (^27, offset: 16)))))) ^21 = gv: (guid: 20, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 5, typeIdInfo: (typeCheckedLoadVCalls: (vFuncId: (^25, offset: 16)))))) ^22 = gv: (guid: 21, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 15, typeIdInfo: (typeTestAssumeConstVCalls: (vFuncId: (^27, offset: 16), args: (42), vFuncId: (^27, offset: 24), args: (43)))))) -^23 = gv: (guid: 22, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 5, typeIdInfo: (typeCheckedLoadConstVCalls: (vFuncId: (^27, offset: 16), args: (42)))))) +^23 = gv: (guid: 22, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 5, typeIdInfo: (typeCheckedLoadConstVCalls: (vFuncId: (^28, offset: 16), args: (42)))))) ; Test TypeId summaries: @@ -88,7 +88,7 @@ ; CHECK: ^20 = gv: (guid: 19, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 8, typeIdInfo: (typeTestAssumeVCalls: (vFuncId: (^27, offset: 16)))))) ; CHECK: ^21 = gv: (guid: 20, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 5, typeIdInfo: (typeCheckedLoadVCalls: (vFuncId: (^25, offset: 16)))))) ; CHECK: ^22 = gv: (guid: 21, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 15, typeIdInfo: (typeTestAssumeConstVCalls: (vFuncId: (^27, offset: 16), args: (42), vFuncId: (^27, offset: 24), args: (43)))))) -; CHECK: ^23 = gv: (guid: 22, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 5, typeIdInfo: (typeCheckedLoadConstVCalls: (vFuncId: (^27, offset: 16), args: (42)))))) +; CHECK: ^23 = gv: (guid: 22, summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 5, typeIdInfo: (typeCheckedLoadConstVCalls: (vFuncId: (^28, offset: 16), args: (42)))))) ; CHECK: ^24 = typeid: (name: "_ZTS1A", summary: (typeTestRes: (kind: allOnes, sizeM1BitWidth: 7), wpdResolutions: ((offset: 0, wpdRes: (kind: branchFunnel)), (offset: 8, wpdRes: (kind: singleImpl, singleImplName: "_ZN1A1nEi")), (offset: 16, wpdRes: (kind: indir, resByArg: (args: (1, 2), byArg: (kind: indir, byte: 2, bit: 3), args: (3), byArg: (kind: uniformRetVal, info: 1), args: (4), byArg: (kind: uniqueRetVal, info: 1), args: (5), byArg: (kind: virtualConstProp))))))) ; guid = 7004155349499253778 ; CHECK: ^25 = typeid: (name: "_ZTS1B", summary: (typeTestRes: (kind: inline, sizeM1BitWidth: 0, alignLog2: 1, sizeM1: 2, bitMask: 3, inlineBits: 4))) ; guid = 6203814149063363976 ; CHECK: ^26 = typeid: (name: "_ZTS1C", summary: (typeTestRes: (kind: single, sizeM1BitWidth: 0))) ; guid = 1884921850105019584 diff --git a/test/ThinLTO/X86/Inputs/cfi-distributed.ll b/test/ThinLTO/X86/Inputs/cfi-distributed.ll new file mode 100644 index 00000000000..376c3f5c157 --- /dev/null +++ b/test/ThinLTO/X86/Inputs/cfi-distributed.ll @@ -0,0 +1,28 @@ +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-grtev4-linux-gnu" + +%struct.B2 = type { %struct.A2 } +%struct.A2 = type { i32 (...)** } + +@_ZTV1B2 = constant { [3 x i8*] } { [3 x i8*] [i8* undef, i8* undef, i8* undef] }, !type !0 + +define void @test2(i8* %b) { +entry: + %0 = bitcast i8* %b to i8** + %vtable2 = load i8*, i8** %0 + %1 = tail call i1 @llvm.type.test(i8* %vtable2, metadata !"_ZTS1A2") + br i1 %1, label %cont, label %trap + +trap: + tail call void @llvm.trap() + unreachable + +cont: + ret void +} + +declare i1 @llvm.type.test(i8*, metadata) +declare void @llvm.trap() + +!0 = !{i64 16, !"_ZTS1A2"} +!1 = !{i64 16, !"_ZTS1B2"} diff --git a/test/ThinLTO/X86/cfi-distributed.ll b/test/ThinLTO/X86/cfi-distributed.ll new file mode 100644 index 00000000000..40753fd2bff --- /dev/null +++ b/test/ThinLTO/X86/cfi-distributed.ll @@ -0,0 +1,60 @@ +; REQUIRES: x86-registered-target + +; Test to ensure that only referenced type ID records are emitted into +; each distributed index file. + +; RUN: opt -thinlto-bc -o %t1.o %s +; RUN: opt -thinlto-bc -o %t2.o %p/Inputs/cfi-distributed.ll + +; RUN: llvm-lto2 run -thinlto-distributed-indexes %t1.o %t2.o \ +; RUN: -o %t3 \ +; RUN: -r=%t1.o,test,px \ +; RUN: -r=%t1.o,_ZTV1B, \ +; RUN: -r=%t1.o,_ZTV1B,px \ +; RUN: -r=%t1.o,test2, \ +; RUN: -r=%t2.o,test2,px \ +; RUN: -r=%t2.o,_ZTV1B2, \ +; RUN: -r=%t2.o,_ZTV1B2,px + +; Since @test calls @test2, the latter should be imported here and the +; first index file should reference both type ids. +; RUN: llvm-dis %t1.o.thinlto.bc -o - | FileCheck %s --check-prefix=INDEX1 +; INDEX1: typeid: (name: "_ZTS1A" +; INDEX1: typeid: (name: "_ZTS1A2" + +; The second index file, corresponding to @test2, should only contain the +; typeid for _ZTS1A. +; RUN: llvm-dis %t2.o.thinlto.bc -o - | FileCheck %s --check-prefix=INDEX2 +; INDEX2-NOT: typeid: (name: "_ZTS1A" +; INDEX2: typeid: (name: "_ZTS1A2" + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-grtev4-linux-gnu" + +%struct.B = type { %struct.A } +%struct.A = type { i32 (...)** } + +@_ZTV1B = constant { [3 x i8*] } { [3 x i8*] [i8* undef, i8* undef, i8* undef] }, !type !0 + +define void @test(i8* %b) { +entry: + tail call void @test2(i8* %b) + %0 = bitcast i8* %b to i8** + %vtable2 = load i8*, i8** %0 + %1 = tail call i1 @llvm.type.test(i8* %vtable2, metadata !"_ZTS1A") + br i1 %1, label %cont, label %trap + +trap: + tail call void @llvm.trap() + unreachable + +cont: + ret void +} + +declare void @test2(i8*) +declare i1 @llvm.type.test(i8*, metadata) +declare void @llvm.trap() + +!0 = !{i64 16, !"_ZTS1A"} +!1 = !{i64 16, !"_ZTS1B"}