From ad414d8634e6c0c3cd1fd4d813ddac950d8cabc5 Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Thu, 22 Mar 2018 18:58:34 +0000 Subject: Pull in r327101 from upstream llvm trunk (by Rafael Espindola): Don't treat .symver as a regular alias definition. This patch starts simplifying the handling of .symver. For now it just moves the responsibility for creating an alias down to the streamer. With that the asm streamer can pass a .symver unchanged, which is nice since gas cannot parse "foo@bar = zed". In a followup I hope to move the handling down to the writer so that we don't need special hacks for avoiding breaking names with @@@ on windows. Pull in r327160 from upstream llvm trunk (by Rafael Espindola): Delay creating an alias for @@@. With this we only create an alias for @@@ once we know if it should use @ or @@. This avoids last minutes renames and hacks to handle MS names. This only handles the ELF writer. LTO still has issues with @@@ aliases. Pull in r327928 from upstream llvm trunk (by Vitaly Buka): Object: Move attribute calculation into RecordStreamer. NFC Summary: Preparation for D44274 Reviewers: pcc, espindola Subscribers: hiraditya Differential Revision: https://reviews.llvm.org/D44276 Pull in r327930 from upstream llvm trunk (by Vitaly Buka): Object: Fix handling of @@@ in .symver directive Summary: name@@@nodename is going to be replaced with name@@nodename if symbols is defined in the assembled file, or name@nodename if undefined. https://sourceware.org/binutils/docs/as/Symver.html Fixes PR36623 Reviewers: pcc, espindola Subscribers: mehdi_amini, hiraditya Differential Revision: https://reviews.llvm.org/D44274 Together, these changes fix handling of @@@ in .symver directives when doing Link Time Optimization. Reported by: Shawn Webb MFC after: 3 months X-MFC-With: r327952 --- contrib/llvm/lib/Object/ModuleSymbolTable.cpp | 80 +-------------------------- 1 file changed, 2 insertions(+), 78 deletions(-) (limited to 'contrib/llvm/lib/Object/ModuleSymbolTable.cpp') diff --git a/contrib/llvm/lib/Object/ModuleSymbolTable.cpp b/contrib/llvm/lib/Object/ModuleSymbolTable.cpp index 64446525b916..f0d70aefd426 100644 --- a/contrib/llvm/lib/Object/ModuleSymbolTable.cpp +++ b/contrib/llvm/lib/Object/ModuleSymbolTable.cpp @@ -24,7 +24,6 @@ #include "llvm/IR/GlobalAlias.h" #include "llvm/IR/GlobalValue.h" #include "llvm/IR/GlobalVariable.h" -#include "llvm/IR/Mangler.h" #include "llvm/IR/Module.h" #include "llvm/MC/MCAsmInfo.h" #include "llvm/MC/MCContext.h" @@ -69,81 +68,6 @@ void ModuleSymbolTable::addModule(Module *M) { }); } -// Ensure ELF .symver aliases get the same binding as the defined symbol -// they alias with. -static void handleSymverAliases(const Module &M, RecordStreamer &Streamer) { - if (Streamer.symverAliases().empty()) - return; - - // The name in the assembler will be mangled, but the name in the IR - // might not, so we first compute a mapping from mangled name to GV. - Mangler Mang; - SmallString<64> MangledName; - StringMap MangledNameMap; - auto GetMangledName = [&](const GlobalValue &GV) { - if (!GV.hasName()) - return; - - MangledName.clear(); - MangledName.reserve(GV.getName().size() + 1); - Mang.getNameWithPrefix(MangledName, &GV, /*CannotUsePrivateLabel=*/false); - MangledNameMap[MangledName] = &GV; - }; - for (const Function &F : M) - GetMangledName(F); - for (const GlobalVariable &GV : M.globals()) - GetMangledName(GV); - for (const GlobalAlias &GA : M.aliases()) - GetMangledName(GA); - - // Walk all the recorded .symver aliases, and set up the binding - // for each alias. - for (auto &Symver : Streamer.symverAliases()) { - const MCSymbol *Aliasee = Symver.first; - MCSymbolAttr Attr = MCSA_Invalid; - - // First check if the aliasee binding was recorded in the asm. - RecordStreamer::State state = Streamer.getSymbolState(Aliasee); - switch (state) { - case RecordStreamer::Global: - case RecordStreamer::DefinedGlobal: - Attr = MCSA_Global; - break; - case RecordStreamer::UndefinedWeak: - case RecordStreamer::DefinedWeak: - Attr = MCSA_Weak; - break; - default: - break; - } - - // If we don't have a symbol attribute from assembly, then check if - // the aliasee was defined in the IR. - if (Attr == MCSA_Invalid) { - const auto *GV = M.getNamedValue(Aliasee->getName()); - if (!GV) { - auto MI = MangledNameMap.find(Aliasee->getName()); - if (MI != MangledNameMap.end()) - GV = MI->second; - else - continue; - } - if (GV->hasExternalLinkage()) - Attr = MCSA_Global; - else if (GV->hasLocalLinkage()) - Attr = MCSA_Local; - else if (GV->isWeakForLinker()) - Attr = MCSA_Weak; - } - if (Attr == MCSA_Invalid) - continue; - - // Set the detected binding on each alias with this aliasee. - for (auto &Alias : Symver.second) - Streamer.EmitSymbolAttribute(Alias, Attr); - } -} - void ModuleSymbolTable::CollectAsmSymbols( const Module &M, function_ref AsmSymbol) { @@ -176,7 +100,7 @@ void ModuleSymbolTable::CollectAsmSymbols( MCObjectFileInfo MOFI; MCContext MCCtx(MAI.get(), MRI.get(), &MOFI); MOFI.InitMCObjectFileInfo(TT, /*PIC*/ false, MCCtx); - RecordStreamer Streamer(MCCtx); + RecordStreamer Streamer(MCCtx, M); T->createNullTargetStreamer(Streamer); std::unique_ptr Buffer(MemoryBuffer::getMemBuffer(InlineAsm)); @@ -195,7 +119,7 @@ void ModuleSymbolTable::CollectAsmSymbols( if (Parser->Run(false)) return; - handleSymverAliases(M, Streamer); + Streamer.flushSymverDirectives(); for (auto &KV : Streamer) { StringRef Key = KV.first(); -- cgit v1.2.3