From be9ffaacfa1bca11df24c1c6621bede0cab92d64 Mon Sep 17 00:00:00 2001 From: Peter Collingbourne Date: Fri, 10 Feb 2017 22:29:38 +0000 Subject: IR: Function summary extensions for whole-program devirtualization pass. The summary information includes all uses of llvm.type.test and llvm.type.checked.load intrinsics that can be used to devirtualize calls, including any constant arguments for virtual constant propagation. Differential Revision: https://reviews.llvm.org/D29734 llvm-svn: 294795 --- llvm/lib/Bitcode/Reader/BitcodeReader.cpp | 44 +++++++++++++++++++++++++-- llvm/lib/Bitcode/Writer/BitcodeWriter.cpp | 49 ++++++++++++++++++++++++++++--- 2 files changed, 87 insertions(+), 6 deletions(-) (limited to 'llvm/lib/Bitcode') diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp index a46e49ccde8..fe73efef5a5 100644 --- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp +++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp @@ -4848,6 +4848,10 @@ Error ModuleSummaryIndexBitcodeReader::parseEntireSummary( GlobalValueSummary *LastSeenSummary = nullptr; bool Combined = false; std::vector PendingTypeTests; + std::vector PendingTypeTestAssumeVCalls, + PendingTypeCheckedLoadVCalls; + std::vector PendingTypeTestAssumeConstVCalls, + PendingTypeCheckedLoadConstVCalls; while (true) { BitstreamEntry Entry = Stream.advanceSkippingSubblocks(); @@ -4914,8 +4918,15 @@ Error ModuleSummaryIndexBitcodeReader::parseEntireSummary( IsOldProfileFormat, HasProfile); auto FS = llvm::make_unique( Flags, InstCount, std::move(Refs), std::move(Calls), - std::move(PendingTypeTests)); + std::move(PendingTypeTests), std::move(PendingTypeTestAssumeVCalls), + std::move(PendingTypeCheckedLoadVCalls), + std::move(PendingTypeTestAssumeConstVCalls), + std::move(PendingTypeCheckedLoadConstVCalls)); PendingTypeTests.clear(); + PendingTypeTestAssumeVCalls.clear(); + PendingTypeCheckedLoadVCalls.clear(); + PendingTypeTestAssumeConstVCalls.clear(); + PendingTypeCheckedLoadConstVCalls.clear(); auto GUID = getGUIDFromValueId(ValueID); FS->setModulePath(TheIndex.addModulePath(ModulePath, 0)->first()); FS->setOriginalName(GUID.second); @@ -4989,8 +5000,15 @@ Error ModuleSummaryIndexBitcodeReader::parseEntireSummary( GlobalValue::GUID GUID = getGUIDFromValueId(ValueID).first; auto FS = llvm::make_unique( Flags, InstCount, std::move(Refs), std::move(Edges), - std::move(PendingTypeTests)); + std::move(PendingTypeTests), std::move(PendingTypeTestAssumeVCalls), + std::move(PendingTypeCheckedLoadVCalls), + std::move(PendingTypeTestAssumeConstVCalls), + std::move(PendingTypeCheckedLoadConstVCalls)); PendingTypeTests.clear(); + PendingTypeTestAssumeVCalls.clear(); + PendingTypeCheckedLoadVCalls.clear(); + PendingTypeTestAssumeConstVCalls.clear(); + PendingTypeCheckedLoadConstVCalls.clear(); LastSeenSummary = FS.get(); FS->setModulePath(ModuleIdMap[ModuleId]); TheIndex.addGlobalValueSummary(GUID, std::move(FS)); @@ -5054,6 +5072,28 @@ Error ModuleSummaryIndexBitcodeReader::parseEntireSummary( Record.end()); break; } + case bitc::FS_TYPE_TEST_ASSUME_VCALLS: { + assert(PendingTypeTestAssumeVCalls.empty()); + for (unsigned I = 0; I != Record.size(); I += 2) + PendingTypeTestAssumeVCalls.push_back({Record[I], Record[I+1]}); + break; + } + case bitc::FS_TYPE_CHECKED_LOAD_VCALLS: { + assert(PendingTypeCheckedLoadVCalls.empty()); + for (unsigned I = 0; I != Record.size(); I += 2) + PendingTypeCheckedLoadVCalls.push_back({Record[I], Record[I+1]}); + break; + } + case bitc::FS_TYPE_TEST_ASSUME_CONST_VCALL: { + PendingTypeTestAssumeConstVCalls.push_back( + {{Record[0], Record[1]}, {Record.begin() + 2, Record.end()}}); + break; + } + case bitc::FS_TYPE_CHECKED_LOAD_CONST_VCALL: { + PendingTypeCheckedLoadConstVCalls.push_back( + {{Record[0], Record[1]}, {Record.begin() + 2, Record.end()}}); + break; + } } } llvm_unreachable("Exit infinite loop"); diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp index 4eac89c37a5..1281fca5f69 100644 --- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp +++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp @@ -3368,6 +3368,49 @@ void IndexBitcodeWriter::writeModStrings() { Stream.ExitBlock(); } +/// 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()) + Stream.EmitRecord(bitc::FS_TYPE_TESTS, FS->type_tests()); + + SmallVector Record; + + auto WriteVFuncIdVec = [&](uint64_t Ty, + ArrayRef VFs) { + if (VFs.empty()) + return; + Record.clear(); + for (auto &VF : VFs) { + Record.push_back(VF.GUID); + Record.push_back(VF.Offset); + } + Stream.EmitRecord(Ty, Record); + }; + + WriteVFuncIdVec(bitc::FS_TYPE_TEST_ASSUME_VCALLS, + FS->type_test_assume_vcalls()); + WriteVFuncIdVec(bitc::FS_TYPE_CHECKED_LOAD_VCALLS, + FS->type_checked_load_vcalls()); + + auto WriteConstVCallVec = [&](uint64_t Ty, + ArrayRef VCs) { + for (auto &VC : VCs) { + Record.clear(); + Record.push_back(VC.VFunc.GUID); + Record.push_back(VC.VFunc.Offset); + Record.insert(Record.end(), VC.Args.begin(), VC.Args.end()); + Stream.EmitRecord(Ty, Record); + } + }; + + WriteConstVCallVec(bitc::FS_TYPE_TEST_ASSUME_CONST_VCALL, + FS->type_test_assume_const_vcalls()); + WriteConstVCallVec(bitc::FS_TYPE_CHECKED_LOAD_CONST_VCALL, + FS->type_checked_load_const_vcalls()); +} + // Helper to emit a single function summary record. void ModuleBitcodeWriter::writePerModuleFunctionSummaryRecord( SmallVector &NameVals, GlobalValueSummary *Summary, @@ -3376,8 +3419,7 @@ void ModuleBitcodeWriter::writePerModuleFunctionSummaryRecord( NameVals.push_back(ValueID); FunctionSummary *FS = cast(Summary); - if (!FS->type_tests().empty()) - Stream.EmitRecord(bitc::FS_TYPE_TESTS, FS->type_tests()); + writeFunctionTypeMetadataRecords(Stream, FS); NameVals.push_back(getEncodedGVSummaryFlags(FS->flags())); NameVals.push_back(FS->instCount()); @@ -3637,8 +3679,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() { } auto *FS = cast(S); - if (!FS->type_tests().empty()) - Stream.EmitRecord(bitc::FS_TYPE_TESTS, FS->type_tests()); + writeFunctionTypeMetadataRecords(Stream, FS); NameVals.push_back(ValueId); NameVals.push_back(Index.getModuleId(FS->modulePath())); -- cgit v1.2.3