From: Fangrui Song Date: Sun, 16 Feb 2020 01:23:18 +0000 (-0800) Subject: [ThinLTO] Drop dso_local if a GlobalVariable satisfies isDeclarationForLinker() X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d2ef8c1f2ca33457247be26374852573098553c7;p=platform%2Fupstream%2Fllvm.git [ThinLTO] Drop dso_local if a GlobalVariable satisfies isDeclarationForLinker() dso_local leads to direct access even if the definition is not within this compilation unit (it is still in the same linkage unit). On ELF, such a relocation (e.g. R_X86_64_PC32) referencing a STB_GLOBAL STV_DEFAULT object can cause a linker error in a -shared link. If the linkage is changed to available_externally, the dso_local flag should be dropped, so that no direct access will be generated. The current behavior is benign, because -fpic does not assume dso_local (clang/lib/CodeGen/CodeGenModule.cpp:shouldAssumeDSOLocal). If we do that for -fno-semantic-interposition (D73865), there will be an R_X86_64_PC32 linker error without this patch. Reviewed By: tejohnson Differential Revision: https://reviews.llvm.org/D74751 --- diff --git a/llvm/include/llvm/Transforms/IPO/FunctionImport.h b/llvm/include/llvm/Transforms/IPO/FunctionImport.h index b4dde7b..6eaf82a 100644 --- a/llvm/include/llvm/Transforms/IPO/FunctionImport.h +++ b/llvm/include/llvm/Transforms/IPO/FunctionImport.h @@ -105,8 +105,10 @@ public: std::function>(StringRef Identifier)>; /// Create a Function Importer. - FunctionImporter(const ModuleSummaryIndex &Index, ModuleLoaderTy ModuleLoader) - : Index(Index), ModuleLoader(std::move(ModuleLoader)) {} + FunctionImporter(const ModuleSummaryIndex &Index, ModuleLoaderTy ModuleLoader, + bool ClearDSOLocalOnDeclarations) + : Index(Index), ModuleLoader(std::move(ModuleLoader)), + ClearDSOLocalOnDeclarations(ClearDSOLocalOnDeclarations) {} /// Import functions in Module \p M based on the supplied import list. Expected importFunctions(Module &M, const ImportMapTy &ImportList); @@ -117,6 +119,10 @@ private: /// Factory function to load a Module for a given identifier ModuleLoaderTy ModuleLoader; + + /// See the comment of ClearDSOLocalOnDeclarations in + /// Utils/FunctionImportUtils.h. + bool ClearDSOLocalOnDeclarations; }; /// The function importing pass diff --git a/llvm/include/llvm/Transforms/Utils/FunctionImportUtils.h b/llvm/include/llvm/Transforms/Utils/FunctionImportUtils.h index 2c6c3ad..acdd8ff 100644 --- a/llvm/include/llvm/Transforms/Utils/FunctionImportUtils.h +++ b/llvm/include/llvm/Transforms/Utils/FunctionImportUtils.h @@ -39,6 +39,19 @@ class FunctionImportGlobalProcessing { /// as part of a different backend compilation process. bool HasExportedFunctions = false; + /// Set to true (only applicatable to ELF -fpic) if dso_local should be + /// dropped for a declaration. + /// + /// On ELF, the assembler is conservative and assumes a global default + /// visibility symbol can be interposable. No direct access relocation is + /// allowed, if the definition is not in the translation unit, even if the + /// definition is available in the linkage unit. Thus we need to clear + /// dso_local to disable direct access. + /// + /// This flag should not be set for -fno-pic or -fpie, which would + /// unnecessarily disable direct access. + bool ClearDSOLocalOnDeclarations; + /// Set of llvm.*used values, in order to validate that we don't try /// to promote any non-renamable values. SmallPtrSet Used; @@ -85,10 +98,11 @@ class FunctionImportGlobalProcessing { GlobalValue::LinkageTypes getLinkage(const GlobalValue *SGV, bool DoPromote); public: - FunctionImportGlobalProcessing( - Module &M, const ModuleSummaryIndex &Index, - SetVector *GlobalsToImport = nullptr) - : M(M), ImportIndex(Index), GlobalsToImport(GlobalsToImport) { + FunctionImportGlobalProcessing(Module &M, const ModuleSummaryIndex &Index, + SetVector *GlobalsToImport, + bool ClearDSOLocalOnDeclarations) + : M(M), ImportIndex(Index), GlobalsToImport(GlobalsToImport), + ClearDSOLocalOnDeclarations(ClearDSOLocalOnDeclarations) { // If we have a ModuleSummaryIndex but no function to import, // then this is the primary module being compiled in a ThinLTO // backend compilation, and we need to see if it has functions that @@ -111,6 +125,7 @@ public: /// exported local functions renamed and promoted for ThinLTO. bool renameModuleForThinLTO( Module &M, const ModuleSummaryIndex &Index, + bool ClearDSOLocalOnDeclarations, SetVector *GlobalsToImport = nullptr); /// Compute synthetic function entry counts. diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp index b749909..dbd6f8c 100644 --- a/llvm/lib/LTO/LTOBackend.cpp +++ b/llvm/lib/LTO/LTOBackend.cpp @@ -521,7 +521,13 @@ Error lto::thinBackend(const Config &Conf, unsigned Task, AddStreamFn AddStream, if (Conf.PreOptModuleHook && !Conf.PreOptModuleHook(Task, Mod)) return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); - renameModuleForThinLTO(Mod, CombinedIndex); + // When linking an ELF shared object, dso_local should be dropped. We + // conservatively do this for -fpic. + bool ClearDSOLocalOnDeclarations = + TM->getTargetTriple().isOSBinFormatELF() && + TM->getRelocationModel() != Reloc::Static && + Mod.getPIELevel() == PIELevel::Default; + renameModuleForThinLTO(Mod, CombinedIndex, ClearDSOLocalOnDeclarations); dropDeadSymbols(Mod, DefinedGlobals, CombinedIndex); @@ -547,7 +553,8 @@ Error lto::thinBackend(const Config &Conf, unsigned Task, AddStreamFn AddStream, /*IsImporting*/ true); }; - FunctionImporter Importer(CombinedIndex, ModuleLoader); + FunctionImporter Importer(CombinedIndex, ModuleLoader, + ClearDSOLocalOnDeclarations); if (Error Err = Importer.importFunctions(Mod, ImportList).takeError()) return Err; diff --git a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp index 0346954..3d8d48d 100644 --- a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp +++ b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp @@ -152,8 +152,9 @@ generateModuleMap(std::vector> &Modules) { return ModuleMap; } -static void promoteModule(Module &TheModule, const ModuleSummaryIndex &Index) { - if (renameModuleForThinLTO(TheModule, Index)) +static void promoteModule(Module &TheModule, const ModuleSummaryIndex &Index, + bool ClearDSOLocalOnDeclarations) { + if (renameModuleForThinLTO(TheModule, Index, ClearDSOLocalOnDeclarations)) report_fatal_error("renameModuleForThinLTO failed"); } @@ -205,15 +206,16 @@ static std::unique_ptr loadModuleFromInput(lto::InputFile *Input, static void crossImportIntoModule(Module &TheModule, const ModuleSummaryIndex &Index, - StringMap &ModuleMap, - const FunctionImporter::ImportMapTy &ImportList) { + StringMap &ModuleMap, + const FunctionImporter::ImportMapTy &ImportList, + bool ClearDSOLocalOnDeclarations) { auto Loader = [&](StringRef Identifier) { auto &Input = ModuleMap[Identifier]; return loadModuleFromInput(Input, TheModule.getContext(), /*Lazy=*/true, /*IsImporting*/ true); }; - FunctionImporter Importer(Index, Loader); + FunctionImporter Importer(Index, Loader, ClearDSOLocalOnDeclarations); Expected Result = Importer.importFunctions(TheModule, ImportList); if (!Result) { handleAllErrors(Result.takeError(), [&](ErrorInfoBase &EIB) { @@ -411,8 +413,15 @@ ProcessThinLTOModule(Module &TheModule, ModuleSummaryIndex &Index, // "Benchmark"-like optimization: single-source case bool SingleModule = (ModuleMap.size() == 1); + // When linking an ELF shared object, dso_local should be dropped. We + // conservatively do this for -fpic. + bool ClearDSOLocalOnDeclarations = + TM.getTargetTriple().isOSBinFormatELF() && + TM.getRelocationModel() != Reloc::Static && + TheModule.getPIELevel() == PIELevel::Default; + if (!SingleModule) { - promoteModule(TheModule, Index); + promoteModule(TheModule, Index, ClearDSOLocalOnDeclarations); // Apply summary-based prevailing-symbol resolution decisions. thinLTOResolvePrevailingInModule(TheModule, DefinedGlobals); @@ -432,7 +441,8 @@ ProcessThinLTOModule(Module &TheModule, ModuleSummaryIndex &Index, saveTempBitcode(TheModule, SaveTempsDir, count, ".2.internalized.bc"); if (!SingleModule) { - crossImportIntoModule(TheModule, Index, ModuleMap, ImportList); + crossImportIntoModule(TheModule, Index, ModuleMap, ImportList, + ClearDSOLocalOnDeclarations); // Save temps: after cross-module import. saveTempBitcode(TheModule, SaveTempsDir, count, ".3.imported.bc"); @@ -673,7 +683,8 @@ void ThinLTOCodeGenerator::promote(Module &TheModule, ModuleSummaryIndex &Index, Index, IsExported(ExportLists, GUIDPreservedSymbols), IsPrevailing(PrevailingCopy)); - promoteModule(TheModule, Index); + // FIXME Set ClearDSOLocalOnDeclarations. + promoteModule(TheModule, Index, /*ClearDSOLocalOnDeclarations=*/false); } /** @@ -705,7 +716,9 @@ void ThinLTOCodeGenerator::crossModuleImport(Module &TheModule, ExportLists); auto &ImportList = ImportLists[TheModule.getModuleIdentifier()]; - crossImportIntoModule(TheModule, Index, ModuleMap, ImportList); + // FIXME Set ClearDSOLocalOnDeclarations. + crossImportIntoModule(TheModule, Index, ModuleMap, ImportList, + /*ClearDSOLocalOnDeclarations=*/false); } /** @@ -832,7 +845,8 @@ void ThinLTOCodeGenerator::internalize(Module &TheModule, Index, IsExported(ExportLists, GUIDPreservedSymbols), IsPrevailing(PrevailingCopy)); - promoteModule(TheModule, Index); + // FIXME Set ClearDSOLocalOnDeclarations. + promoteModule(TheModule, Index, /*ClearDSOLocalOnDeclarations=*/false); // Internalization thinLTOResolvePrevailingInModule( diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp index 792c14d..2ebd5cb 100644 --- a/llvm/lib/Transforms/IPO/FunctionImport.cpp +++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp @@ -1233,7 +1233,8 @@ Expected FunctionImporter::importFunctions( UpgradeDebugInfo(*SrcModule); // Link in the specified functions. - if (renameModuleForThinLTO(*SrcModule, Index, &GlobalsToImport)) + if (renameModuleForThinLTO(*SrcModule, Index, ClearDSOLocalOnDeclarations, + &GlobalsToImport)) return true; if (PrintImports) { @@ -1302,7 +1303,8 @@ static bool doImportingForModule(Module &M) { // Next we need to promote to global scope and rename any local values that // are potentially exported to other modules. - if (renameModuleForThinLTO(M, *Index, nullptr)) { + if (renameModuleForThinLTO(M, *Index, /*clearDSOOnDeclarations=*/false, + /*GlobalsToImport=*/nullptr)) { errs() << "Error renaming module\n"; return false; } @@ -1311,7 +1313,8 @@ static bool doImportingForModule(Module &M) { auto ModuleLoader = [&M](StringRef Identifier) { return loadFile(std::string(Identifier), M.getContext()); }; - FunctionImporter Importer(*Index, ModuleLoader); + FunctionImporter Importer(*Index, ModuleLoader, + /*ClearDSOLocalOnDeclarations=*/false); Expected Result = Importer.importFunctions(M, ImportList); // FIXME: Probably need to propagate Errors through the pass manager. diff --git a/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp b/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp index 26d48ee..8df7ae9 100644 --- a/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp +++ b/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp @@ -212,13 +212,6 @@ void FunctionImportGlobalProcessing::processGlobalForThinLTO(GlobalValue &GV) { } } } - // Check the summaries to see if the symbol gets resolved to a known local - // definition. - if (VI && VI.isDSOLocal()) { - GV.setDSOLocal(true); - if (GV.hasDLLImportStorageClass()) - GV.setDLLStorageClass(GlobalValue::DefaultStorageClass); - } } // We should always have a ValueInfo (i.e. GV in index) for definitions when @@ -280,6 +273,20 @@ void FunctionImportGlobalProcessing::processGlobalForThinLTO(GlobalValue &GV) { } else GV.setLinkage(getLinkage(&GV, /* DoPromote */ false)); + // When ClearDSOLocalOnDeclarations is true, clear dso_local if GV is + // converted to a declaration, to disable direct access. Don't do this if GV + // is implicitly dso_local due to a non-default visibility. + if (ClearDSOLocalOnDeclarations && GV.isDeclarationForLinker() && + !GV.isImplicitDSOLocal()) { + GV.setDSOLocal(false); + } else if (VI && VI.isDSOLocal()) { + // If all summaries are dso_local, symbol gets resolved to a known local + // definition. + GV.setDSOLocal(true); + if (GV.hasDLLImportStorageClass()) + GV.setDLLStorageClass(GlobalValue::DefaultStorageClass); + } + // Remove functions imported as available externally defs from comdats, // as this is a declaration for the linker, and will be dropped eventually. // It is illegal for comdats to contain declarations. @@ -319,7 +326,9 @@ bool FunctionImportGlobalProcessing::run() { } bool llvm::renameModuleForThinLTO(Module &M, const ModuleSummaryIndex &Index, + bool ClearDSOLocalOnDeclarations, SetVector *GlobalsToImport) { - FunctionImportGlobalProcessing ThinLTOProcessing(M, Index, GlobalsToImport); + FunctionImportGlobalProcessing ThinLTOProcessing(M, Index, GlobalsToImport, + ClearDSOLocalOnDeclarations); return ThinLTOProcessing.run(); } diff --git a/llvm/test/LTO/Resolution/X86/local-def-dllimport.ll b/llvm/test/LTO/Resolution/X86/local-def-dllimport.ll index 4c70e72..25b69b7 100644 --- a/llvm/test/LTO/Resolution/X86/local-def-dllimport.ll +++ b/llvm/test/LTO/Resolution/X86/local-def-dllimport.ll @@ -13,9 +13,7 @@ target triple = "x86_64-unknown-linux-gnu" $g = comdat any @g = global i8 42, comdat, !type !0 -; CHECK: define -; CHECK-NOT: dllimport -; CHECK-SAME: @f +; CHECK: define available_externally dllimport i8* @f() define available_externally dllimport i8* @f() { ret i8* @g } diff --git a/llvm/test/ThinLTO/X86/Inputs/index-const-prop-gvref.ll b/llvm/test/ThinLTO/X86/Inputs/index-const-prop-gvref.ll index 5302076..28a58b3 100644 --- a/llvm/test/ThinLTO/X86/Inputs/index-const-prop-gvref.ll +++ b/llvm/test/ThinLTO/X86/Inputs/index-const-prop-gvref.ll @@ -1,5 +1,5 @@ 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" -@b = global i32* @a, align 8 -@a = global i32 42, align 4 +@b = dso_local global i32* @a, align 8 +@a = dso_local global i32 42, align 4 diff --git a/llvm/test/ThinLTO/X86/funcimport_alwaysinline.ll b/llvm/test/ThinLTO/X86/funcimport_alwaysinline.ll index aa49476..c43c1d5 100644 --- a/llvm/test/ThinLTO/X86/funcimport_alwaysinline.ll +++ b/llvm/test/ThinLTO/X86/funcimport_alwaysinline.ll @@ -11,7 +11,7 @@ ; foo() being always_inline should be imported irrespective of the ; instruction limit -; CHECK1: define available_externally dso_local void @foo() +; CHECK1: define available_externally void @foo() target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" diff --git a/llvm/test/ThinLTO/X86/index-const-prop-alias.ll b/llvm/test/ThinLTO/X86/index-const-prop-alias.ll index bd15b5a..4a1e68f 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop-alias.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop-alias.ll @@ -16,15 +16,15 @@ ; RUN: llvm-dis %t5.1.3.import.bc -o - | FileCheck %s --check-prefix=PRESERVED ; We currently don't support importing aliases -; IMPORT: @g.alias = external dso_local global i32 +; IMPORT: @g.alias = external global i32 ; IMPORT-NEXT: @g = internal global i32 42, align 4 #0 ; IMPORT: attributes #0 = { "thinlto-internalize" } ; CODEGEN: define dso_local i32 @main ; CODEGEN-NEXT: ret i32 42 -; PRESERVED: @g.alias = external dso_local global i32 -; PRESERVED-NEXT: @g = available_externally dso_local global i32 42, align 4 +; PRESERVED: @g.alias = external global i32 +; PRESERVED-NEXT: @g = available_externally global i32 42, align 4 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" diff --git a/llvm/test/ThinLTO/X86/index-const-prop-comdat.ll b/llvm/test/ThinLTO/X86/index-const-prop-comdat.ll index 2fdc793..d90bcba 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop-comdat.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop-comdat.ll @@ -4,7 +4,7 @@ ; RUN: llvm-dis %t3.2.3.import.bc -o - | FileCheck %s ; Comdats are not internalized even if they are read only. -; CHECK: @g = available_externally dso_local global i32 42 +; CHECK: @g = available_externally global i32 42 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" diff --git a/llvm/test/ThinLTO/X86/index-const-prop-dead.ll b/llvm/test/ThinLTO/X86/index-const-prop-dead.ll index 44fc350..6766a5e 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop-dead.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop-dead.ll @@ -6,7 +6,7 @@ ; Dead globals are converted to declarations by ThinLTO in dropDeadSymbols ; If we try to internalize such we'll get a broken module. -; CHECK: @g = external dso_local global i32 +; CHECK: @g = external global i32 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" diff --git a/llvm/test/ThinLTO/X86/index-const-prop-full-lto.ll b/llvm/test/ThinLTO/X86/index-const-prop-full-lto.ll index f6260c5..0b9412a 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop-full-lto.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop-full-lto.ll @@ -8,7 +8,7 @@ ; All references from functions in full LTO module are not constant. ; We cannot internalize @g -; CHECK: @g = available_externally dso_local global i32 42 +; CHECK: @g = available_externally global i32 42 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" diff --git a/llvm/test/ThinLTO/X86/index-const-prop-gvref-pie.ll b/llvm/test/ThinLTO/X86/index-const-prop-gvref-pie.ll new file mode 100644 index 0000000..62c4164 --- /dev/null +++ b/llvm/test/ThinLTO/X86/index-const-prop-gvref-pie.ll @@ -0,0 +1,28 @@ +;; The same as index-const-prop-gvref.ll, except for PIE. +; RUN: opt -module-summary %s -o %t1.bc +; RUN: opt -module-summary %p/Inputs/index-const-prop-gvref.ll -o %t2.bc +; RUN: llvm-lto2 run -save-temps %t2.bc -r=%t2.bc,b,pl -r=%t2.bc,a,pl \ +; RUN: %t1.bc -r=%t1.bc,main,plx -r=%t1.bc,a, -r=%t1.bc,b, -o %t3 +; RUN: llvm-dis %t3.2.3.import.bc -o - | FileCheck %s --check-prefix=DEST + +;; For PIE, keep dso_local for declarations to enable direct access. +; DEST: @b = external dso_local global i32* +; DEST-NEXT: @a = available_externally dso_local global i32 42, align 4 + +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" + +@a = external global i32 +@b = external global i32* + +define i32 @main() { + %p = load i32*, i32** @b, align 8 + store i32 33, i32* %p, align 4 + %v = load i32, i32* @a, align 4 + ret i32 %v +} + +!llvm.module.flags = !{!0} + +!0 = !{i32 7, !"PIE Level", i32 2} +!1 = !{i32 7, !"PIC Level", i32 2} diff --git a/llvm/test/ThinLTO/X86/index-const-prop-gvref.ll b/llvm/test/ThinLTO/X86/index-const-prop-gvref.ll index 9722837..293eb1d 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop-gvref.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop-gvref.ll @@ -1,17 +1,41 @@ ; RUN: opt -module-summary %s -o %t1.bc ; RUN: opt -module-summary %p/Inputs/index-const-prop-gvref.ll -o %t2.bc -; RUN: llvm-lto2 run -save-temps %t2.bc -r=%t2.bc,b,pl -r=%t2.bc,a,pl \ -; RUN: %t1.bc -r=%t1.bc,main,plx -r=%t1.bc,a, -r=%t1.bc,b, -o %t3 +; RUN: llvm-lto2 run -relocation-model=static -save-temps %t2.bc -r=%t2.bc,b,pl -r=%t2.bc,a,pl \ +; RUN: %t1.bc -r=%t1.bc,main,plx -r=%t1.bc,a, -r=%t1.bc,b, -o %t3 ; RUN: llvm-dis %t3.1.3.import.bc -o - | FileCheck %s --check-prefix=SRC ; RUN: llvm-dis %t3.2.3.import.bc -o - | FileCheck %s --check-prefix=DEST +;; When producing an ELF DSO, clear dso_local for declarations to avoid direct access. +; RUN: llvm-lto2 run -relocation-model=pic -save-temps %t2.bc -r=%t2.bc,b,pl -r=%t2.bc,a,pl \ +; RUN: %t1.bc -r=%t1.bc,main,plx -r=%t1.bc,a, -r=%t1.bc,b, -o %t4 +; RUN: llvm-dis %t4.1.3.import.bc -o - | FileCheck %s --check-prefix=SRC +; RUN: llvm-dis %t4.2.3.import.bc -o - | FileCheck %s --check-prefix=DEST_DSO + ; No variable in the source module should have been internalized ; SRC: @b = dso_local global i32* @a ; SRC-NEXT: @a = dso_local global i32 42 ; We can't internalize globals referenced by other live globals -; DEST: @b = external dso_local global i32* -; DEST-NEXT: @a = available_externally dso_local global i32 42, align 4 +; DEST: @b = external dso_local global i32* +; DEST-NEXT: @a = available_externally dso_local global i32 42, align 4 +; DEST_DSO: @b = external global i32* +; DEST_DSO-NEXT: @a = available_externally global i32 42, align 4 + +;; Test old API. +;; When producing an ELF DSO, clear dso_local for declarations to avoid direct access. +; RUN: llvm-lto -thinlto-action=run %t2.bc %t1.bc -relocation-model=static -thinlto-save-temps=%t5. +; RUN: llvm-dis < %t5.0.3.imported.bc | FileCheck %s --check-prefix=OLDAPI_SRC +; RUN: llvm-dis < %t5.1.3.imported.bc | FileCheck %s --check-prefix=OLDAPI_DST +; RUN: llvm-lto -thinlto-action=run %t2.bc %t1.bc -relocation-model=pic -thinlto-save-temps=%t6. +; RUN: llvm-dis < %t6.0.3.imported.bc | FileCheck %s --check-prefix=OLDAPI_SRC +; RUN: llvm-dis < %t6.1.3.imported.bc | FileCheck %s --check-prefix=OLDAPI_DST_DSO + +; OLDAPI_SRC: @b = internal global i32* @a, align 8 +; OLDAPI_SRC-NEXT: @a = dso_local global i32 42, align 4 +; OLDAPI_DST: @b = external dso_local global i32* +; OLDAPI_DST-NEXT: @a = available_externally dso_local global i32 42, align 4 +; OLDAPI_DST_DSO: @b = external global i32* +; OLDAPI_DST_DSO-NEXT: @a = available_externally global i32 42, align 4 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" diff --git a/llvm/test/ThinLTO/X86/index-const-prop-ldst.ll b/llvm/test/ThinLTO/X86/index-const-prop-ldst.ll index 3c6d03c..7c0f822 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop-ldst.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop-ldst.ll @@ -5,7 +5,7 @@ ; The 'store' instruction in @main should prevent internalization ; even when there is 'load' instruction before it. -; CHECK: @g = available_externally dso_local global i32 42 +; CHECK: @g = available_externally global i32 42 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" diff --git a/llvm/test/ThinLTO/X86/index-const-prop-linkage.ll b/llvm/test/ThinLTO/X86/index-const-prop-linkage.ll index 2c7c794..9eb85da 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop-linkage.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop-linkage.ll @@ -11,7 +11,7 @@ ; - reference from @llvm.used ; CHECK: @llvm.used = appending global [1 x i32*] [i32* @g2] ; CHECK-NEXT: @g1 = external dso_local global i32, align 4 -; CHECK-NEXT: @g2 = available_externally dso_local global i32 42, align 4 +; CHECK-NEXT: @g2 = available_externally global i32 42, align 4 ; CHECK-NEXT: @g3 = available_externally global i32 42, align 4 target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" diff --git a/llvm/test/ThinLTO/X86/index-const-prop2.ll b/llvm/test/ThinLTO/X86/index-const-prop2.ll index 928d00a..5bf40fc 100644 --- a/llvm/test/ThinLTO/X86/index-const-prop2.ll +++ b/llvm/test/ThinLTO/X86/index-const-prop2.ll @@ -68,7 +68,7 @@ ; CODEGEN: i32 @main() ; CODEGEN-NEXT: ret i32 3 -; IMPORT2: @gBar = available_externally dso_local local_unnamed_addr global i32 2, align 4 +; IMPORT2: @gBar = available_externally local_unnamed_addr global i32 2, align 4 ; CODEGEN2: i32 @main2 ; CODEGEN2-NEXT: %1 = tail call i32 @rand() diff --git a/llvm/tools/llvm-link/llvm-link.cpp b/llvm/tools/llvm-link/llvm-link.cpp index d0c2b45..d99659f 100644 --- a/llvm/tools/llvm-link/llvm-link.cpp +++ b/llvm/tools/llvm-link/llvm-link.cpp @@ -266,7 +266,8 @@ static bool importFunctions(const char *argv0, Module &DestModule) { auto CachedModuleLoader = [&](StringRef Identifier) { return ModuleLoaderCache.takeModule(std::string(Identifier)); }; - FunctionImporter Importer(*Index, CachedModuleLoader); + FunctionImporter Importer(*Index, CachedModuleLoader, + /*ClearDSOLocalOnDeclarations=*/false); ExitOnErr(Importer.importFunctions(DestModule, ImportList)); return true; @@ -313,7 +314,8 @@ static bool linkFiles(const char *argv0, LLVMContext &Context, Linker &L, } // Promotion - if (renameModuleForThinLTO(*M, *Index)) + if (renameModuleForThinLTO(*M, *Index, + /*ClearDSOLocalOnDeclarations=*/false)) return true; }