| //===- MinGW.cpp ----------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "MinGW.h" |
| #include "SymbolTable.h" |
| #include "lld/Common/ErrorHandler.h" |
| #include "llvm/Object/COFF.h" |
| #include "llvm/Support/Path.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| using namespace lld; |
| using namespace lld::coff; |
| using namespace llvm; |
| using namespace llvm::COFF; |
| |
| AutoExporter::AutoExporter() { |
| excludeLibs = { |
| "libgcc", |
| "libgcc_s", |
| "libstdc++", |
| "libmingw32", |
| "libmingwex", |
| "libg2c", |
| "libsupc++", |
| "libobjc", |
| "libgcj", |
| "libclang_rt.builtins", |
| "libclang_rt.builtins-aarch64", |
| "libclang_rt.builtins-arm", |
| "libclang_rt.builtins-i386", |
| "libclang_rt.builtins-x86_64", |
| "libc++", |
| "libc++abi", |
| "libunwind", |
| "libmsvcrt", |
| "libucrtbase", |
| }; |
| |
| excludeObjects = { |
| "crt0.o", "crt1.o", "crt1u.o", "crt2.o", "crt2u.o", "dllcrt1.o", |
| "dllcrt2.o", "gcrt0.o", "gcrt1.o", "gcrt2.o", "crtbegin.o", "crtend.o", |
| }; |
| |
| excludeSymbolPrefixes = { |
| // Import symbols |
| "__imp_", |
| "__IMPORT_DESCRIPTOR_", |
| // Extra import symbols from GNU import libraries |
| "__nm_", |
| // C++ symbols |
| "__rtti_", |
| "__builtin_", |
| // Artifical symbols such as .refptr |
| ".", |
| }; |
| |
| excludeSymbolSuffixes = { |
| "_iname", |
| "_NULL_THUNK_DATA", |
| }; |
| |
| if (config->machine == I386) { |
| excludeSymbols = { |
| "__NULL_IMPORT_DESCRIPTOR", |
| "__pei386_runtime_relocator", |
| "_do_pseudo_reloc", |
| "_impure_ptr", |
| "__impure_ptr", |
| "__fmode", |
| "_environ", |
| "___dso_handle", |
| // These are the MinGW names that differ from the standard |
| // ones (lacking an extra underscore). |
| "_DllMain@12", |
| "_DllEntryPoint@12", |
| "_DllMainCRTStartup@12", |
| }; |
| excludeSymbolPrefixes.insert("__head_"); |
| } else { |
| excludeSymbols = { |
| "__NULL_IMPORT_DESCRIPTOR", |
| "_pei386_runtime_relocator", |
| "do_pseudo_reloc", |
| "impure_ptr", |
| "_impure_ptr", |
| "_fmode", |
| "environ", |
| "__dso_handle", |
| // These are the MinGW names that differ from the standard |
| // ones (lacking an extra underscore). |
| "DllMain", |
| "DllEntryPoint", |
| "DllMainCRTStartup", |
| }; |
| excludeSymbolPrefixes.insert("_head_"); |
| } |
| } |
| |
| void AutoExporter::addWholeArchive(StringRef path) { |
| StringRef libName = sys::path::filename(path); |
| // Drop the file extension, to match the processing below. |
| libName = libName.substr(0, libName.rfind('.')); |
| excludeLibs.erase(libName); |
| } |
| |
| bool AutoExporter::shouldExport(Defined *sym) const { |
| if (!sym || !sym->isLive() || !sym->getChunk()) |
| return false; |
| |
| // Only allow the symbol kinds that make sense to export; in particular, |
| // disallow import symbols. |
| if (!isa<DefinedRegular>(sym) && !isa<DefinedCommon>(sym)) |
| return false; |
| if (excludeSymbols.count(sym->getName())) |
| return false; |
| |
| for (StringRef prefix : excludeSymbolPrefixes.keys()) |
| if (sym->getName().startswith(prefix)) |
| return false; |
| for (StringRef suffix : excludeSymbolSuffixes.keys()) |
| if (sym->getName().endswith(suffix)) |
| return false; |
| |
| // If a corresponding __imp_ symbol exists and is defined, don't export it. |
| if (symtab->find(("__imp_" + sym->getName()).str())) |
| return false; |
| |
| // Check that file is non-null before dereferencing it, symbols not |
| // originating in regular object files probably shouldn't be exported. |
| if (!sym->getFile()) |
| return false; |
| |
| StringRef libName = sys::path::filename(sym->getFile()->parentName); |
| |
| // Drop the file extension. |
| libName = libName.substr(0, libName.rfind('.')); |
| if (!libName.empty()) |
| return !excludeLibs.count(libName); |
| |
| StringRef fileName = sys::path::filename(sym->getFile()->getName()); |
| return !excludeObjects.count(fileName); |
| } |
| |
| void coff::writeDefFile(StringRef name) { |
| std::error_code ec; |
| raw_fd_ostream os(name, ec, sys::fs::OF_None); |
| if (ec) |
| fatal("cannot open " + name + ": " + ec.message()); |
| |
| os << "EXPORTS\n"; |
| for (Export &e : config->exports) { |
| os << " " << e.exportName << " " |
| << "@" << e.ordinal; |
| if (auto *def = dyn_cast_or_null<Defined>(e.sym)) { |
| if (def && def->getChunk() && |
| !(def->getChunk()->getOutputCharacteristics() & IMAGE_SCN_MEM_EXECUTE)) |
| os << " DATA"; |
| } |
| os << "\n"; |
| } |
| } |