//
//===----------------------------------------------------------------------===//
-#include "llvm/Config/config.h"
-#include "plugin-api.h"
-
-#include "llvm-c/lto.h"
-
-#include "llvm/Support/ToolOutputFile.h"
-#include "llvm/System/Errno.h"
-#include "llvm/System/Path.h"
-#include "llvm/System/Program.h"
-
-#include <cerrno>
-#include <cstdlib>
-#include <cstring>
-#include <fstream>
+#include "llvm/Config/config.h" // plugin-api.h requires HAVE_STDINT_H
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/CodeGen/Analysis.h"
+#include "llvm/CodeGen/CommandFlags.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Verifier.h"
+#include "llvm/Linker/Linker.h"
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/Object/IRObjectFile.h"
+#include "llvm/PassManager.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Target/TargetLibraryInfo.h"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/IPO/PassManagerBuilder.h"
+#include "llvm/Transforms/Utils/GlobalStatus.h"
+#include "llvm/Transforms/Utils/ModuleUtils.h"
+#include "llvm/Transforms/Utils/ValueMapper.h"
#include <list>
+#include <plugin-api.h>
+#include <system_error>
#include <vector>
+#ifndef LDPO_PIE
+// FIXME: remove this declaration when we stop maintaining Ubuntu Quantal and
+// Precise and Debian Wheezy (binutils 2.23 is required)
+# define LDPO_PIE 3
+#endif
+
using namespace llvm;
namespace {
- ld_plugin_status discard_message(int level, const char *format, ...) {
- // Die loudly. Recent versions of Gold pass ld_plugin_message as the first
- // callback in the transfer vector. This should never be called.
- abort();
- }
+struct claimed_file {
+ void *handle;
+ std::vector<ld_plugin_symbol> syms;
+};
+}
- ld_plugin_add_symbols add_symbols = NULL;
- ld_plugin_get_symbols get_symbols = NULL;
- ld_plugin_add_input_file add_input_file = NULL;
- ld_plugin_add_input_library add_input_library = NULL;
- ld_plugin_set_extra_library_path set_extra_library_path = NULL;
- ld_plugin_message message = discard_message;
-
- int api_version = 0;
- int gold_version = 0;
-
- struct claimed_file {
- lto_module_t M;
- void *handle;
- std::vector<ld_plugin_symbol> syms;
- };
-
- lto_codegen_model output_type = LTO_CODEGEN_PIC_MODEL_STATIC;
- std::string output_name = "";
- std::list<claimed_file> Modules;
- std::vector<sys::Path> Cleanup;
+static ld_plugin_status discard_message(int level, const char *format, ...) {
+ // Die loudly. Recent versions of Gold pass ld_plugin_message as the first
+ // callback in the transfer vector. This should never be called.
+ abort();
}
+static ld_plugin_get_input_file get_input_file = nullptr;
+static ld_plugin_release_input_file release_input_file = nullptr;
+static ld_plugin_add_symbols add_symbols = nullptr;
+static ld_plugin_get_symbols get_symbols = nullptr;
+static ld_plugin_add_input_file add_input_file = nullptr;
+static ld_plugin_set_extra_library_path set_extra_library_path = nullptr;
+static ld_plugin_get_view get_view = nullptr;
+static ld_plugin_message message = discard_message;
+static Reloc::Model RelocationModel = Reloc::Default;
+static std::string output_name = "";
+static std::list<claimed_file> Modules;
+static std::vector<std::string> Cleanup;
+static llvm::TargetOptions TargetOpts;
+
namespace options {
enum generate_bc { BC_NO, BC_ALSO, BC_ONLY };
static bool generate_api_file = false;
static generate_bc generate_bc_file = BC_NO;
static std::string bc_path;
- static std::string as_path;
- static std::vector<std::string> as_args;
- static std::vector<std::string> pass_through;
+ static std::string obj_path;
static std::string extra_library_path;
static std::string triple;
static std::string mcpu;
// as plugin exclusive to pass to the code generator.
// For example, "generate-api-file" and "as"options are for the plugin
// use only and will not be passed.
- static std::vector<std::string> extra;
+ static std::vector<const char *> extra;
static void process_plugin_option(const char* opt_)
{
- if (opt_ == NULL)
+ if (opt_ == nullptr)
return;
llvm::StringRef opt = opt_;
generate_api_file = true;
} else if (opt.startswith("mcpu=")) {
mcpu = opt.substr(strlen("mcpu="));
- } else if (opt.startswith("as=")) {
- if (!as_path.empty()) {
- (*message)(LDPL_WARNING, "Path to as specified twice. "
- "Discarding %s", opt_);
- } else {
- as_path = opt.substr(strlen("as="));
- }
- } else if (opt.startswith("as-arg=")) {
- llvm::StringRef item = opt.substr(strlen("as-arg="));
- as_args.push_back(item.str());
} else if (opt.startswith("extra-library-path=")) {
extra_library_path = opt.substr(strlen("extra_library_path="));
- } else if (opt.startswith("pass-through=")) {
- llvm::StringRef item = opt.substr(strlen("pass-through="));
- pass_through.push_back(item.str());
} else if (opt.startswith("mtriple=")) {
triple = opt.substr(strlen("mtriple="));
+ } else if (opt.startswith("obj-path=")) {
+ obj_path = opt.substr(strlen("obj-path="));
} else if (opt == "emit-llvm") {
generate_bc_file = BC_ONLY;
} else if (opt == "also-emit-llvm") {
llvm::StringRef path = opt.substr(strlen("also-emit-llvm="));
generate_bc_file = BC_ALSO;
if (!bc_path.empty()) {
- (*message)(LDPL_WARNING, "Path to the output IL file specified twice. "
- "Discarding %s", opt_);
+ message(LDPL_WARNING, "Path to the output IL file specified twice. "
+ "Discarding %s",
+ opt_);
} else {
bc_path = path;
}
} else {
// Save this option to pass to the code generator.
- extra.push_back(opt);
+ // ParseCommandLineOptions() expects argv[0] to be program name. Lazily
+ // add that.
+ if (extra.empty())
+ extra.push_back("LLVMgold");
+
+ extra.push_back(opt_);
}
}
}
extern "C" ld_plugin_status onload(ld_plugin_tv *tv);
ld_plugin_status onload(ld_plugin_tv *tv) {
+ InitializeAllTargetInfos();
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ InitializeAllAsmParsers();
+ InitializeAllAsmPrinters();
+
// We're given a pointer to the first transfer vector. We read through them
// until we find one where tv_tag == LDPT_NULL. The REGISTER_* tagged values
// contain pointers to functions that we need to call to register our own
// for services.
bool registeredClaimFile = false;
+ bool RegisteredAllSymbolsRead = false;
for (; tv->tv_tag != LDPT_NULL; ++tv) {
switch (tv->tv_tag) {
- case LDPT_API_VERSION:
- api_version = tv->tv_u.tv_val;
- break;
- case LDPT_GOLD_VERSION: // major * 100 + minor
- gold_version = tv->tv_u.tv_val;
- break;
case LDPT_OUTPUT_NAME:
output_name = tv->tv_u.tv_string;
break;
switch (tv->tv_u.tv_val) {
case LDPO_REL: // .o
case LDPO_DYN: // .so
- output_type = LTO_CODEGEN_PIC_MODEL_DYNAMIC;
+ case LDPO_PIE: // position independent executable
+ RelocationModel = Reloc::PIC_;
break;
case LDPO_EXEC: // .exe
- output_type = LTO_CODEGEN_PIC_MODEL_STATIC;
+ RelocationModel = Reloc::Static;
break;
default:
- (*message)(LDPL_ERROR, "Unknown output file type %d",
- tv->tv_u.tv_val);
+ message(LDPL_ERROR, "Unknown output file type %d", tv->tv_u.tv_val);
return LDPS_ERR;
}
- // TODO: add an option to disable PIC.
- //output_type = LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC;
break;
case LDPT_OPTION:
options::process_plugin_option(tv->tv_u.tv_string);
ld_plugin_register_claim_file callback;
callback = tv->tv_u.tv_register_claim_file;
- if ((*callback)(claim_file_hook) != LDPS_OK)
+ if (callback(claim_file_hook) != LDPS_OK)
return LDPS_ERR;
registeredClaimFile = true;
ld_plugin_register_all_symbols_read callback;
callback = tv->tv_u.tv_register_all_symbols_read;
- if ((*callback)(all_symbols_read_hook) != LDPS_OK)
+ if (callback(all_symbols_read_hook) != LDPS_OK)
return LDPS_ERR;
+
+ RegisteredAllSymbolsRead = true;
} break;
case LDPT_REGISTER_CLEANUP_HOOK: {
ld_plugin_register_cleanup callback;
callback = tv->tv_u.tv_register_cleanup;
- if ((*callback)(cleanup_hook) != LDPS_OK)
+ if (callback(cleanup_hook) != LDPS_OK)
return LDPS_ERR;
} break;
+ case LDPT_GET_INPUT_FILE:
+ get_input_file = tv->tv_u.tv_get_input_file;
+ break;
+ case LDPT_RELEASE_INPUT_FILE:
+ release_input_file = tv->tv_u.tv_release_input_file;
+ break;
case LDPT_ADD_SYMBOLS:
add_symbols = tv->tv_u.tv_add_symbols;
break;
- case LDPT_GET_SYMBOLS:
+ case LDPT_GET_SYMBOLS_V2:
get_symbols = tv->tv_u.tv_get_symbols;
break;
case LDPT_ADD_INPUT_FILE:
add_input_file = tv->tv_u.tv_add_input_file;
break;
- case LDPT_ADD_INPUT_LIBRARY:
- add_input_library = tv->tv_u.tv_add_input_file;
- break;
case LDPT_SET_EXTRA_LIBRARY_PATH:
set_extra_library_path = tv->tv_u.tv_set_extra_library_path;
break;
+ case LDPT_GET_VIEW:
+ get_view = tv->tv_u.tv_get_view;
+ break;
case LDPT_MESSAGE:
message = tv->tv_u.tv_message;
break;
}
if (!registeredClaimFile) {
- (*message)(LDPL_ERROR, "register_claim_file not passed to LLVMgold.");
+ message(LDPL_ERROR, "register_claim_file not passed to LLVMgold.");
return LDPS_ERR;
}
if (!add_symbols) {
- (*message)(LDPL_ERROR, "add_symbols not passed to LLVMgold.");
+ message(LDPL_ERROR, "add_symbols not passed to LLVMgold.");
+ return LDPS_ERR;
+ }
+
+ if (!RegisteredAllSymbolsRead)
+ return LDPS_OK;
+
+ if (!get_input_file) {
+ message(LDPL_ERROR, "get_input_file not passed to LLVMgold.");
+ return LDPS_ERR;
+ }
+ if (!release_input_file) {
+ message(LDPL_ERROR, "relesase_input_file not passed to LLVMgold.");
return LDPS_ERR;
}
return LDPS_OK;
}
-/// claim_file_hook - called by gold to see whether this file is one that
-/// our plugin can handle. We'll try to open it and register all the symbols
-/// with add_symbol if possible.
+static const GlobalObject *getBaseObject(const GlobalValue &GV) {
+ if (auto *GA = dyn_cast<GlobalAlias>(&GV))
+ return GA->getBaseObject();
+ return cast<GlobalObject>(&GV);
+}
+
+/// Called by gold to see whether this file is one that our plugin can handle.
+/// We'll try to open it and register all the symbols with add_symbol if
+/// possible.
static ld_plugin_status claim_file_hook(const ld_plugin_input_file *file,
int *claimed) {
- void *buf = NULL;
- if (file->offset) {
- // Gold has found what might be IR part-way inside of a file, such as
- // an .a archive.
- if (lseek(file->fd, file->offset, SEEK_SET) == -1) {
- (*message)(LDPL_ERROR,
- "Failed to seek to archive member of %s at offset %d: %s\n",
- file->name,
- file->offset, sys::StrError(errno).c_str());
+ LLVMContext Context;
+ MemoryBufferRef BufferRef;
+ std::unique_ptr<MemoryBuffer> Buffer;
+ if (get_view) {
+ const void *view;
+ if (get_view(file->handle, &view) != LDPS_OK) {
+ message(LDPL_ERROR, "Failed to get a view of %s", file->name);
return LDPS_ERR;
}
- buf = malloc(file->filesize);
- if (!buf) {
- (*message)(LDPL_ERROR,
- "Failed to allocate buffer for archive member of size: %d\n",
- file->filesize);
- return LDPS_ERR;
+ BufferRef = MemoryBufferRef(StringRef((const char *)view, file->filesize), "");
+ } else {
+ int64_t offset = 0;
+ // Gold has found what might be IR part-way inside of a file, such as
+ // an .a archive.
+ if (file->offset) {
+ offset = file->offset;
}
- if (read(file->fd, buf, file->filesize) != file->filesize) {
- (*message)(LDPL_ERROR,
- "Failed to read archive member of %s at offset %d: %s\n",
- file->name,
- file->offset,
- sys::StrError(errno).c_str());
- free(buf);
+ ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
+ MemoryBuffer::getOpenFileSlice(file->fd, file->name, file->filesize,
+ offset);
+ if (std::error_code EC = BufferOrErr.getError()) {
+ message(LDPL_ERROR, EC.message().c_str());
return LDPS_ERR;
}
- if (!lto_module_is_object_file_in_memory(buf, file->filesize)) {
- free(buf);
- return LDPS_OK;
- }
- } else if (!lto_module_is_object_file(file->name))
+ Buffer = std::move(BufferOrErr.get());
+ BufferRef = Buffer->getMemBufferRef();
+ }
+
+ ErrorOr<std::unique_ptr<object::IRObjectFile>> ObjOrErr =
+ object::IRObjectFile::createIRObjectFile(BufferRef, Context);
+ std::error_code EC = ObjOrErr.getError();
+ if (EC == BitcodeError::InvalidBitcodeSignature ||
+ EC == object::object_error::invalid_file_type ||
+ EC == object::object_error::bitcode_section_not_found)
return LDPS_OK;
*claimed = 1;
- Modules.resize(Modules.size() + 1);
- claimed_file &cf = Modules.back();
- cf.M = buf ? lto_module_create_from_memory(buf, file->filesize) :
- lto_module_create(file->name);
- free(buf);
- if (!cf.M) {
- (*message)(LDPL_ERROR, "Failed to create LLVM module: %s",
- lto_get_error_message());
+ if (EC) {
+ message(LDPL_ERROR, "LLVM gold plugin has failed to create LTO module: %s",
+ EC.message().c_str());
return LDPS_ERR;
}
+ std::unique_ptr<object::IRObjectFile> Obj = std::move(*ObjOrErr);
- if (!options::triple.empty())
- lto_module_set_target_triple(cf.M, options::triple.c_str());
+ Modules.resize(Modules.size() + 1);
+ claimed_file &cf = Modules.back();
cf.handle = file->handle;
- unsigned sym_count = lto_module_get_num_symbols(cf.M);
- cf.syms.reserve(sym_count);
- for (unsigned i = 0; i != sym_count; ++i) {
- lto_symbol_attributes attrs = lto_module_get_symbol_attribute(cf.M, i);
- if ((attrs & LTO_SYMBOL_SCOPE_MASK) == LTO_SYMBOL_SCOPE_INTERNAL)
+ for (auto &Sym : Obj->symbols()) {
+ uint32_t Symflags = Sym.getFlags();
+ if (!(Symflags & object::BasicSymbolRef::SF_Global))
+ continue;
+
+ if (Symflags & object::BasicSymbolRef::SF_FormatSpecific)
continue;
cf.syms.push_back(ld_plugin_symbol());
ld_plugin_symbol &sym = cf.syms.back();
- sym.name = const_cast<char *>(lto_module_get_symbol_name(cf.M, i));
- sym.version = NULL;
+ sym.version = nullptr;
- int scope = attrs & LTO_SYMBOL_SCOPE_MASK;
- switch (scope) {
- case LTO_SYMBOL_SCOPE_HIDDEN:
+ SmallString<64> Name;
+ {
+ raw_svector_ostream OS(Name);
+ Sym.printName(OS);
+ }
+ sym.name = strdup(Name.c_str());
+
+ const GlobalValue *GV = Obj->getSymbolGV(Sym.getRawDataRefImpl());
+
+ sym.visibility = LDPV_DEFAULT;
+ if (GV) {
+ switch (GV->getVisibility()) {
+ case GlobalValue::DefaultVisibility:
+ sym.visibility = LDPV_DEFAULT;
+ break;
+ case GlobalValue::HiddenVisibility:
sym.visibility = LDPV_HIDDEN;
break;
- case LTO_SYMBOL_SCOPE_PROTECTED:
+ case GlobalValue::ProtectedVisibility:
sym.visibility = LDPV_PROTECTED;
break;
- case 0: // extern
- case LTO_SYMBOL_SCOPE_DEFAULT:
- sym.visibility = LDPV_DEFAULT;
- break;
- default:
- (*message)(LDPL_ERROR, "Unknown scope attribute: %d", scope);
- return LDPS_ERR;
+ }
}
- int definition = attrs & LTO_SYMBOL_DEFINITION_MASK;
- switch (definition) {
- case LTO_SYMBOL_DEFINITION_REGULAR:
- sym.def = LDPK_DEF;
- break;
- case LTO_SYMBOL_DEFINITION_UNDEFINED:
- sym.def = LDPK_UNDEF;
- break;
- case LTO_SYMBOL_DEFINITION_TENTATIVE:
- sym.def = LDPK_COMMON;
- break;
- case LTO_SYMBOL_DEFINITION_WEAK:
- sym.def = LDPK_WEAKDEF;
- break;
- case LTO_SYMBOL_DEFINITION_WEAKUNDEF:
+ if (Symflags & object::BasicSymbolRef::SF_Undefined) {
+ sym.def = LDPK_UNDEF;
+ if (GV && GV->hasExternalWeakLinkage())
sym.def = LDPK_WEAKUNDEF;
- break;
- default:
- (*message)(LDPL_ERROR, "Unknown definition attribute: %d", definition);
- return LDPS_ERR;
+ } else {
+ sym.def = LDPK_DEF;
+ if (GV) {
+ assert(!GV->hasExternalWeakLinkage() &&
+ !GV->hasAvailableExternallyLinkage() && "Not a declaration!");
+ if (GV->hasCommonLinkage())
+ sym.def = LDPK_COMMON;
+ else if (GV->isWeakForLinker())
+ sym.def = LDPK_WEAKDEF;
+ }
}
- // LLVM never emits COMDAT.
sym.size = 0;
- sym.comdat_key = NULL;
+ sym.comdat_key = nullptr;
+ if (GV) {
+ const GlobalObject *Base = getBaseObject(*GV);
+ if (!Base)
+ message(LDPL_FATAL, "Unable to determine comdat of alias!");
+ const Comdat *C = Base->getComdat();
+ if (C)
+ sym.comdat_key = strdup(C->getName().str().c_str());
+ else if (Base->hasWeakLinkage() || Base->hasLinkOnceLinkage())
+ sym.comdat_key = strdup(sym.name);
+ }
sym.resolution = LDPR_UNKNOWN;
}
- cf.syms.reserve(cf.syms.size());
-
if (!cf.syms.empty()) {
- if ((*add_symbols)(cf.handle, cf.syms.size(), &cf.syms[0]) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Unable to add symbols!");
+ if (add_symbols(cf.handle, cf.syms.size(), &cf.syms[0]) != LDPS_OK) {
+ message(LDPL_ERROR, "Unable to add symbols!");
return LDPS_ERR;
}
}
return LDPS_OK;
}
-/// all_symbols_read_hook - gold informs us that all symbols have been read.
-/// At this point, we use get_symbols to see if any of our definitions have
-/// been overridden by a native object file. Then, perform optimization and
-/// codegen.
-static ld_plugin_status all_symbols_read_hook(void) {
- lto_code_gen_t cg = lto_codegen_create();
-
- for (std::list<claimed_file>::iterator I = Modules.begin(),
- E = Modules.end(); I != E; ++I)
- lto_codegen_add_module(cg, I->M);
-
- std::ofstream api_file;
- if (options::generate_api_file) {
- api_file.open("apifile.txt", std::ofstream::out | std::ofstream::trunc);
- if (!api_file.is_open()) {
- (*message)(LDPL_FATAL, "Unable to open apifile.txt for writing.");
- abort();
+static void keepGlobalValue(GlobalValue &GV,
+ std::vector<GlobalAlias *> &KeptAliases) {
+ assert(!GV.hasLocalLinkage());
+
+ if (auto *GA = dyn_cast<GlobalAlias>(&GV))
+ KeptAliases.push_back(GA);
+
+ switch (GV.getLinkage()) {
+ default:
+ break;
+ case GlobalValue::LinkOnceAnyLinkage:
+ GV.setLinkage(GlobalValue::WeakAnyLinkage);
+ break;
+ case GlobalValue::LinkOnceODRLinkage:
+ GV.setLinkage(GlobalValue::WeakODRLinkage);
+ break;
+ }
+
+ assert(!GV.isDiscardableIfUnused());
+}
+
+static void internalize(GlobalValue &GV) {
+ if (GV.isDeclarationForLinker())
+ return; // We get here if there is a matching asm definition.
+ if (!GV.hasLocalLinkage())
+ GV.setLinkage(GlobalValue::InternalLinkage);
+}
+
+static void drop(GlobalValue &GV) {
+ if (auto *F = dyn_cast<Function>(&GV)) {
+ F->deleteBody();
+ F->setComdat(nullptr); // Should deleteBody do this?
+ return;
+ }
+
+ if (auto *Var = dyn_cast<GlobalVariable>(&GV)) {
+ Var->setInitializer(nullptr);
+ Var->setLinkage(
+ GlobalValue::ExternalLinkage); // Should setInitializer do this?
+ Var->setComdat(nullptr); // and this?
+ return;
+ }
+
+ auto &Alias = cast<GlobalAlias>(GV);
+ Module &M = *Alias.getParent();
+ PointerType &Ty = *cast<PointerType>(Alias.getType());
+ GlobalValue::LinkageTypes L = Alias.getLinkage();
+ auto *Var =
+ new GlobalVariable(M, Ty.getElementType(), /*isConstant*/ false, L,
+ /*Initializer*/ nullptr);
+ Var->takeName(&Alias);
+ Alias.replaceAllUsesWith(Var);
+ Alias.eraseFromParent();
+}
+
+static const char *getResolutionName(ld_plugin_symbol_resolution R) {
+ switch (R) {
+ case LDPR_UNKNOWN:
+ return "UNKNOWN";
+ case LDPR_UNDEF:
+ return "UNDEF";
+ case LDPR_PREVAILING_DEF:
+ return "PREVAILING_DEF";
+ case LDPR_PREVAILING_DEF_IRONLY:
+ return "PREVAILING_DEF_IRONLY";
+ case LDPR_PREEMPTED_REG:
+ return "PREEMPTED_REG";
+ case LDPR_PREEMPTED_IR:
+ return "PREEMPTED_IR";
+ case LDPR_RESOLVED_IR:
+ return "RESOLVED_IR";
+ case LDPR_RESOLVED_EXEC:
+ return "RESOLVED_EXEC";
+ case LDPR_RESOLVED_DYN:
+ return "RESOLVED_DYN";
+ case LDPR_PREVAILING_DEF_IRONLY_EXP:
+ return "PREVAILING_DEF_IRONLY_EXP";
+ }
+ llvm_unreachable("Unknown resolution");
+}
+
+static GlobalObject *makeInternalReplacement(GlobalObject *GO) {
+ Module *M = GO->getParent();
+ GlobalObject *Ret;
+ if (auto *F = dyn_cast<Function>(GO)) {
+ if (F->isMaterializable()) {
+ if (F->materialize())
+ message(LDPL_FATAL, "LLVM gold plugin has failed to read a function");
+
+ }
+
+ auto *NewF = Function::Create(F->getFunctionType(), F->getLinkage(),
+ F->getName(), M);
+
+ ValueToValueMapTy VM;
+ Function::arg_iterator NewI = NewF->arg_begin();
+ for (auto &Arg : F->args()) {
+ NewI->setName(Arg.getName());
+ VM[&Arg] = NewI;
+ ++NewI;
+ }
+
+ NewF->getBasicBlockList().splice(NewF->end(), F->getBasicBlockList());
+ for (auto &BB : *NewF) {
+ for (auto &Inst : BB)
+ RemapInstruction(&Inst, VM, RF_IgnoreMissingEntries);
}
+
+ Ret = NewF;
+ F->deleteBody();
+ } else {
+ auto *Var = cast<GlobalVariable>(GO);
+ Ret = new GlobalVariable(
+ *M, Var->getType()->getElementType(), Var->isConstant(),
+ Var->getLinkage(), Var->getInitializer(), Var->getName(),
+ nullptr, Var->getThreadLocalMode(), Var->getType()->getAddressSpace(),
+ Var->isExternallyInitialized());
+ Var->setInitializer(nullptr);
}
+ Ret->copyAttributesFrom(GO);
+ Ret->setLinkage(GlobalValue::InternalLinkage);
+ Ret->setComdat(GO->getComdat());
+
+ return Ret;
+}
+
+namespace {
+class LocalValueMaterializer : public ValueMaterializer {
+ DenseSet<GlobalValue *> &Dropped;
+
+public:
+ LocalValueMaterializer(DenseSet<GlobalValue *> &Dropped) : Dropped(Dropped) {}
+ Value *materializeValueFor(Value *V) override;
+};
+}
+
+Value *LocalValueMaterializer::materializeValueFor(Value *V) {
+ auto *GV = dyn_cast<GlobalValue>(V);
+ if (!GV)
+ return nullptr;
+ if (!Dropped.count(GV))
+ return nullptr;
+ assert(!isa<GlobalAlias>(GV) && "Found alias point to weak alias.");
+ return makeInternalReplacement(cast<GlobalObject>(GV));
+}
+
+static Constant *mapConstantToLocalCopy(Constant *C, ValueToValueMapTy &VM,
+ LocalValueMaterializer *Materializer) {
+ return MapValue(C, VM, RF_IgnoreMissingEntries, nullptr, Materializer);
+}
+
+static std::unique_ptr<Module>
+getModuleForFile(LLVMContext &Context, claimed_file &F, raw_fd_ostream *ApiFile,
+ StringSet<> &Internalize, StringSet<> &Maybe) {
+ ld_plugin_input_file File;
+ if (get_input_file(F.handle, &File) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get file information");
+
+ if (get_symbols(F.handle, F.syms.size(), &F.syms[0]) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get symbol information");
+
+ const void *View;
+ if (get_view(F.handle, &View) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to get a view of file");
+
+ llvm::ErrorOr<MemoryBufferRef> MBOrErr =
+ object::IRObjectFile::findBitcodeInMemBuffer(
+ MemoryBufferRef(StringRef((const char *)View, File.filesize), ""));
+ if (std::error_code EC = MBOrErr.getError())
+ message(LDPL_FATAL, "Could not read bitcode from file : %s",
+ EC.message().c_str());
+
+ std::unique_ptr<MemoryBuffer> Buffer =
+ MemoryBuffer::getMemBuffer(MBOrErr->getBuffer(), "", false);
+
+ if (release_input_file(F.handle) != LDPS_OK)
+ message(LDPL_FATAL, "Failed to release file information");
+
+ ErrorOr<Module *> MOrErr = getLazyBitcodeModule(std::move(Buffer), Context);
+
+ if (std::error_code EC = MOrErr.getError())
+ message(LDPL_FATAL, "Could not read bitcode from file : %s",
+ EC.message().c_str());
+
+ std::unique_ptr<Module> M(MOrErr.get());
+
+ SmallPtrSet<GlobalValue *, 8> Used;
+ collectUsedGlobalVariables(*M, Used, /*CompilerUsed*/ false);
- // If we don't preserve any symbols, libLTO will assume that all symbols are
- // needed. Keep all symbols unless we're producing a final executable.
- bool anySymbolsPreserved = false;
- for (std::list<claimed_file>::iterator I = Modules.begin(),
- E = Modules.end(); I != E; ++I) {
- (*get_symbols)(I->handle, I->syms.size(), &I->syms[0]);
- for (unsigned i = 0, e = I->syms.size(); i != e; i++) {
- if (I->syms[i].resolution == LDPR_PREVAILING_DEF) {
- lto_codegen_add_must_preserve_symbol(cg, I->syms[i].name);
- anySymbolsPreserved = true;
-
- if (options::generate_api_file)
- api_file << I->syms[i].name << "\n";
+ DenseSet<GlobalValue *> Drop;
+ std::vector<GlobalAlias *> KeptAliases;
+ for (ld_plugin_symbol &Sym : F.syms) {
+ ld_plugin_symbol_resolution Resolution =
+ (ld_plugin_symbol_resolution)Sym.resolution;
+
+ if (options::generate_api_file)
+ *ApiFile << Sym.name << ' ' << getResolutionName(Resolution) << '\n';
+
+ GlobalValue *GV = M->getNamedValue(Sym.name);
+ if (!GV)
+ continue; // Asm symbol.
+
+ if (Resolution != LDPR_PREVAILING_DEF_IRONLY && GV->hasCommonLinkage()) {
+ // Common linkage is special. There is no single symbol that wins the
+ // resolution. Instead we have to collect the maximum alignment and size.
+ // The IR linker does that for us if we just pass it every common GV.
+ // We still have to keep track of LDPR_PREVAILING_DEF_IRONLY so we
+ // internalize once the IR linker has done its job.
+ continue;
+ }
+
+ switch (Resolution) {
+ case LDPR_UNKNOWN:
+ llvm_unreachable("Unexpected resolution");
+
+ case LDPR_RESOLVED_IR:
+ case LDPR_RESOLVED_EXEC:
+ case LDPR_RESOLVED_DYN:
+ case LDPR_UNDEF:
+ assert(GV->isDeclarationForLinker());
+ break;
+
+ case LDPR_PREVAILING_DEF_IRONLY: {
+ keepGlobalValue(*GV, KeptAliases);
+ if (!Used.count(GV)) {
+ // Since we use the regular lib/Linker, we cannot just internalize GV
+ // now or it will not be copied to the merged module. Instead we force
+ // it to be copied and then internalize it.
+ Internalize.insert(Sym.name);
}
+ break;
+ }
+
+ case LDPR_PREVAILING_DEF:
+ keepGlobalValue(*GV, KeptAliases);
+ break;
+
+ case LDPR_PREEMPTED_IR:
+ // Gold might have selected a linkonce_odr and preempted a weak_odr.
+ // In that case we have to make sure we don't end up internalizing it.
+ if (!GV->isDiscardableIfUnused())
+ Maybe.erase(Sym.name);
+
+ // fall-through
+ case LDPR_PREEMPTED_REG:
+ Drop.insert(GV);
+ break;
+
+ case LDPR_PREVAILING_DEF_IRONLY_EXP: {
+ // We can only check for address uses after we merge the modules. The
+ // reason is that this GV might have a copy in another module
+ // and in that module the address might be significant, but that
+ // copy will be LDPR_PREEMPTED_IR.
+ if (GV->hasLinkOnceODRLinkage())
+ Maybe.insert(Sym.name);
+ keepGlobalValue(*GV, KeptAliases);
+ break;
}
+ }
+
+ free(Sym.name);
+ free(Sym.comdat_key);
+ Sym.name = nullptr;
+ Sym.comdat_key = nullptr;
}
- if (options::generate_api_file)
- api_file.close();
+ ValueToValueMapTy VM;
+ LocalValueMaterializer Materializer(Drop);
+ for (GlobalAlias *GA : KeptAliases) {
+ // Gold told us to keep GA. It is possible that a GV usied in the aliasee
+ // expression is being dropped. If that is the case, that GV must be copied.
+ Constant *Aliasee = GA->getAliasee();
+ Constant *Replacement = mapConstantToLocalCopy(Aliasee, VM, &Materializer);
+ if (Aliasee != Replacement)
+ GA->setAliasee(Replacement);
+ }
- if (!anySymbolsPreserved) {
- // All of the IL is unnecessary!
- lto_codegen_dispose(cg);
- return LDPS_OK;
+ for (auto *GV : Drop)
+ drop(*GV);
+
+ return M;
+}
+
+static void runLTOPasses(Module &M, TargetMachine &TM) {
+ PassManager passes;
+ PassManagerBuilder PMB;
+ PMB.LibraryInfo = new TargetLibraryInfo(Triple(TM.getTargetTriple()));
+ PMB.Inliner = createFunctionInliningPass();
+ PMB.VerifyInput = true;
+ PMB.VerifyOutput = true;
+ PMB.populateLTOPassManager(passes, &TM);
+ passes.run(M);
+}
+
+static void codegen(Module &M) {
+ const std::string &TripleStr = M.getTargetTriple();
+ Triple TheTriple(TripleStr);
+
+ std::string ErrMsg;
+ const Target *TheTarget = TargetRegistry::lookupTarget(TripleStr, ErrMsg);
+ if (!TheTarget)
+ message(LDPL_FATAL, "Target not found: %s", ErrMsg.c_str());
+
+ if (unsigned NumOpts = options::extra.size())
+ cl::ParseCommandLineOptions(NumOpts, &options::extra[0]);
+
+ SubtargetFeatures Features;
+ Features.getDefaultSubtargetFeatures(TheTriple);
+ for (const std::string &A : MAttrs)
+ Features.AddFeature(A);
+
+ TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
+ std::unique_ptr<TargetMachine> TM(TheTarget->createTargetMachine(
+ TripleStr, options::mcpu, Features.getString(), Options, RelocationModel,
+ CodeModel::Default, CodeGenOpt::Aggressive));
+
+ runLTOPasses(M, *TM);
+
+ PassManager CodeGenPasses;
+ CodeGenPasses.add(new DataLayoutPass());
+
+ SmallString<128> Filename;
+ int FD;
+ if (options::obj_path.empty()) {
+ std::error_code EC =
+ sys::fs::createTemporaryFile("lto-llvm", "o", FD, Filename);
+ if (EC)
+ message(LDPL_FATAL, "Could not create temorary file: %s",
+ EC.message().c_str());
+ } else {
+ Filename = options::obj_path;
+ std::error_code EC =
+ sys::fs::openFileForWrite(Filename.c_str(), FD, sys::fs::F_None);
+ if (EC)
+ message(LDPL_FATAL, "Could not open file: %s", EC.message().c_str());
}
- lto_codegen_set_pic_model(cg, output_type);
- lto_codegen_set_debug_model(cg, LTO_DEBUG_MODEL_DWARF);
- if (!options::as_path.empty()) {
- sys::Path p = sys::Program::FindProgramByName(options::as_path);
- lto_codegen_set_assembler_path(cg, p.c_str());
+ {
+ raw_fd_ostream OS(FD, true);
+ formatted_raw_ostream FOS(OS);
+
+ if (TM->addPassesToEmitFile(CodeGenPasses, FOS,
+ TargetMachine::CGFT_ObjectFile))
+ message(LDPL_FATAL, "Failed to setup codegen");
+ CodeGenPasses.run(M);
}
- if (!options::as_args.empty()) {
- std::vector<const char *> as_args_p;
- for (std::vector<std::string>::iterator I = options::as_args.begin(),
- E = options::as_args.end(); I != E; ++I) {
- as_args_p.push_back(I->c_str());
+
+ if (add_input_file(Filename.c_str()) != LDPS_OK)
+ message(LDPL_FATAL,
+ "Unable to add .o file to the link. File left behind in: %s",
+ Filename.c_str());
+
+ if (options::obj_path.empty())
+ Cleanup.push_back(Filename.c_str());
+}
+
+/// gold informs us that all symbols have been read. At this point, we use
+/// get_symbols to see if any of our definitions have been overridden by a
+/// native object file. Then, perform optimization and codegen.
+static ld_plugin_status allSymbolsReadHook(raw_fd_ostream *ApiFile) {
+ if (Modules.empty())
+ return LDPS_OK;
+
+ LLVMContext Context;
+ std::unique_ptr<Module> Combined(new Module("ld-temp.o", Context));
+ Linker L(Combined.get());
+
+ std::string DefaultTriple = sys::getDefaultTargetTriple();
+
+ StringSet<> Internalize;
+ StringSet<> Maybe;
+ for (claimed_file &F : Modules) {
+ std::unique_ptr<Module> M =
+ getModuleForFile(Context, F, ApiFile, Internalize, Maybe);
+ if (!options::triple.empty())
+ M->setTargetTriple(options::triple.c_str());
+ else if (M->getTargetTriple().empty()) {
+ M->setTargetTriple(DefaultTriple);
}
- lto_codegen_set_assembler_args(cg, &as_args_p[0], as_args_p.size());
+
+ if (L.linkInModule(M.get()))
+ message(LDPL_FATAL, "Failed to link module");
}
- if (!options::mcpu.empty())
- lto_codegen_set_cpu(cg, options::mcpu.c_str());
-
- // Pass through extra options to the code generator.
- if (!options::extra.empty()) {
- for (std::vector<std::string>::iterator it = options::extra.begin();
- it != options::extra.end(); ++it) {
- lto_codegen_debug_options(cg, (*it).c_str());
- }
+
+ for (const auto &Name : Internalize) {
+ GlobalValue *GV = Combined->getNamedValue(Name.first());
+ if (GV)
+ internalize(*GV);
}
+ for (const auto &Name : Maybe) {
+ GlobalValue *GV = Combined->getNamedValue(Name.first());
+ if (!GV)
+ continue;
+ GV->setLinkage(GlobalValue::LinkOnceODRLinkage);
+ if (canBeOmittedFromSymbolTable(GV))
+ internalize(*GV);
+ }
if (options::generate_bc_file != options::BC_NO) {
std::string path;
path = options::bc_path;
else
path = output_name + ".bc";
- bool err = lto_codegen_write_merged_modules(cg, path.c_str());
- if (err)
- (*message)(LDPL_FATAL, "Failed to write the output file.");
+ {
+ std::error_code EC;
+ raw_fd_ostream OS(path, EC, sys::fs::OpenFlags::F_None);
+ if (EC)
+ message(LDPL_FATAL, "Failed to write the output file.");
+ WriteBitcodeToFile(L.getModule(), OS);
+ }
if (options::generate_bc_file == options::BC_ONLY)
- exit(0);
- }
- size_t bufsize = 0;
- const char *buffer = static_cast<const char *>(lto_codegen_compile(cg,
- &bufsize));
-
- std::string ErrMsg;
-
- sys::Path uniqueObjPath("/tmp/llvmgold.o");
- if (uniqueObjPath.createTemporaryFileOnDisk(true, &ErrMsg)) {
- (*message)(LDPL_ERROR, "%s", ErrMsg.c_str());
- return LDPS_ERR;
- }
- tool_output_file objFile(uniqueObjPath.c_str(), ErrMsg,
- raw_fd_ostream::F_Binary);
- if (!ErrMsg.empty()) {
- (*message)(LDPL_ERROR, "%s", ErrMsg.c_str());
- return LDPS_ERR;
- }
-
- objFile.os().write(buffer, bufsize);
- objFile.os().close();
- if (objFile.os().has_error()) {
- (*message)(LDPL_ERROR, "Error writing output file '%s'",
- uniqueObjPath.c_str());
- objFile.os().clear_error();
- return LDPS_ERR;
+ return LDPS_OK;
}
- objFile.keep();
- lto_codegen_dispose(cg);
-
- if ((*add_input_file)(uniqueObjPath.c_str()) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Unable to add .o file to the link.");
- (*message)(LDPL_ERROR, "File left behind in: %s", uniqueObjPath.c_str());
- return LDPS_ERR;
- }
+ codegen(*L.getModule());
if (!options::extra_library_path.empty() &&
- set_extra_library_path(options::extra_library_path.c_str()) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Unable to set the extra library path.");
- return LDPS_ERR;
- }
+ set_extra_library_path(options::extra_library_path.c_str()) != LDPS_OK)
+ message(LDPL_FATAL, "Unable to set the extra library path.");
- for (std::vector<std::string>::iterator i = options::pass_through.begin(),
- e = options::pass_through.end();
- i != e; ++i) {
- std::string &item = *i;
- const char *item_p = item.c_str();
- if (llvm::StringRef(item).startswith("-l")) {
- if (add_input_library(item_p + 2) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Unable to add library to the link.");
- return LDPS_ERR;
- }
- } else {
- if (add_input_file(item_p) != LDPS_OK) {
- (*message)(LDPL_ERROR, "Unable to add .o file to the link.");
- return LDPS_ERR;
- }
- }
+ return LDPS_OK;
+}
+
+static ld_plugin_status all_symbols_read_hook(void) {
+ ld_plugin_status Ret;
+ if (!options::generate_api_file) {
+ Ret = allSymbolsReadHook(nullptr);
+ } else {
+ std::error_code EC;
+ raw_fd_ostream ApiFile("apifile.txt", EC, sys::fs::F_None);
+ if (EC)
+ message(LDPL_FATAL, "Unable to open apifile.txt for writing: %s",
+ EC.message().c_str());
+ Ret = allSymbolsReadHook(&ApiFile);
}
- Cleanup.push_back(uniqueObjPath);
+ if (options::generate_bc_file == options::BC_ONLY)
+ exit(0);
- return LDPS_OK;
+ return Ret;
}
static ld_plugin_status cleanup_hook(void) {
- std::string ErrMsg;
-
- for (int i = 0, e = Cleanup.size(); i != e; ++i)
- if (Cleanup[i].eraseFromDisk(false, &ErrMsg))
- (*message)(LDPL_ERROR, "Failed to delete '%s': %s", Cleanup[i].c_str(),
- ErrMsg.c_str());
+ for (std::string &Name : Cleanup) {
+ std::error_code EC = sys::fs::remove(Name);
+ if (EC)
+ message(LDPL_ERROR, "Failed to delete '%s': %s", Name.c_str(),
+ EC.message().c_str());
+ }
return LDPS_OK;
}
projects / oota-llvm.git / blobdiff