llvm-6502/tools/llvm-nm/llvm-nm.cpp
Bill Wendling 5e721d7682 Implement the "linker_private_weak" linkage type. This will be used for
Objective-C metadata types which should be marked as "weak", but which the
linker will remove upon final linkage. However, this linkage isn't specific to
Objective-C.

For example, the "objc_msgSend_fixup_alloc" symbol is defined like this:

      .globl l_objc_msgSend_fixup_alloc
      .weak_definition l_objc_msgSend_fixup_alloc
      .section __DATA, __objc_msgrefs, coalesced
      .align 3
l_objc_msgSend_fixup_alloc:
       .quad   _objc_msgSend_fixup
       .quad   L_OBJC_METH_VAR_NAME_1

This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".

Currently only supported on Darwin platforms.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107433 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-01 21:55:59 +00:00

197 lines
7.4 KiB
C++

//===-- llvm-nm.cpp - Symbol table dumping utility for llvm ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This program is a utility that works like traditional Unix "nm",
// that is, it prints out the names of symbols in a bitcode file,
// along with some information about each symbol.
//
// This "nm" does not print symbols' addresses. It supports many of
// the features of GNU "nm", including its different output formats.
//
//===----------------------------------------------------------------------===//
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/Bitcode/Archive.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/System/Signals.h"
#include <algorithm>
#include <cctype>
#include <cerrno>
#include <cstring>
using namespace llvm;
namespace {
enum OutputFormatTy { bsd, sysv, posix };
cl::opt<OutputFormatTy>
OutputFormat("format",
cl::desc("Specify output format"),
cl::values(clEnumVal(bsd, "BSD format"),
clEnumVal(sysv, "System V format"),
clEnumVal(posix, "POSIX.2 format"),
clEnumValEnd), cl::init(bsd));
cl::alias OutputFormat2("f", cl::desc("Alias for --format"),
cl::aliasopt(OutputFormat));
cl::list<std::string>
InputFilenames(cl::Positional, cl::desc("<input bitcode files>"),
cl::ZeroOrMore);
cl::opt<bool> UndefinedOnly("undefined-only",
cl::desc("Show only undefined symbols"));
cl::alias UndefinedOnly2("u", cl::desc("Alias for --undefined-only"),
cl::aliasopt(UndefinedOnly));
cl::opt<bool> DefinedOnly("defined-only",
cl::desc("Show only defined symbols"));
cl::opt<bool> ExternalOnly("extern-only",
cl::desc("Show only external symbols"));
cl::alias ExternalOnly2("g", cl::desc("Alias for --extern-only"),
cl::aliasopt(ExternalOnly));
cl::opt<bool> BSDFormat("B", cl::desc("Alias for --format=bsd"));
cl::opt<bool> POSIXFormat("P", cl::desc("Alias for --format=posix"));
bool MultipleFiles = false;
std::string ToolName;
}
static char TypeCharForSymbol(GlobalValue &GV) {
if (GV.isDeclaration()) return 'U';
if (GV.hasLinkOnceLinkage()) return 'C';
if (GV.hasCommonLinkage()) return 'C';
if (GV.hasWeakLinkage()) return 'W';
if (isa<Function>(GV) && GV.hasInternalLinkage()) return 't';
if (isa<Function>(GV)) return 'T';
if (isa<GlobalVariable>(GV) && GV.hasInternalLinkage()) return 'd';
if (isa<GlobalVariable>(GV)) return 'D';
if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(&GV)) {
const GlobalValue *AliasedGV = GA->getAliasedGlobal();
if (isa<Function>(AliasedGV)) return 'T';
if (isa<GlobalVariable>(AliasedGV)) return 'D';
}
return '?';
}
static void DumpSymbolNameForGlobalValue(GlobalValue &GV) {
// Private linkage and available_externally linkage don't exist in symtab.
if (GV.hasPrivateLinkage() || GV.hasLinkerPrivateLinkage() ||
GV.hasLinkerPrivateWeakLinkage() || GV.hasAvailableExternallyLinkage())
return;
const std::string SymbolAddrStr = " "; // Not used yet...
char TypeChar = TypeCharForSymbol(GV);
if ((TypeChar != 'U') && UndefinedOnly)
return;
if ((TypeChar == 'U') && DefinedOnly)
return;
if (GV.hasLocalLinkage () && ExternalOnly)
return;
if (OutputFormat == posix) {
outs() << GV.getName () << " " << TypeCharForSymbol(GV) << " "
<< SymbolAddrStr << "\n";
} else if (OutputFormat == bsd) {
outs() << SymbolAddrStr << " " << TypeCharForSymbol(GV) << " "
<< GV.getName () << "\n";
} else if (OutputFormat == sysv) {
std::string PaddedName (GV.getName ());
while (PaddedName.length () < 20)
PaddedName += " ";
outs() << PaddedName << "|" << SymbolAddrStr << "| "
<< TypeCharForSymbol(GV)
<< " | | | |\n";
}
}
static void DumpSymbolNamesFromModule(Module *M) {
const std::string &Filename = M->getModuleIdentifier ();
if (OutputFormat == posix && MultipleFiles) {
outs() << Filename << ":\n";
} else if (OutputFormat == bsd && MultipleFiles) {
outs() << "\n" << Filename << ":\n";
} else if (OutputFormat == sysv) {
outs() << "\n\nSymbols from " << Filename << ":\n\n"
<< "Name Value Class Type"
<< " Size Line Section\n";
}
std::for_each (M->begin(), M->end(), DumpSymbolNameForGlobalValue);
std::for_each (M->global_begin(), M->global_end(),
DumpSymbolNameForGlobalValue);
std::for_each (M->alias_begin(), M->alias_end(),
DumpSymbolNameForGlobalValue);
}
static void DumpSymbolNamesFromFile(std::string &Filename) {
LLVMContext &Context = getGlobalContext();
std::string ErrorMessage;
sys::Path aPath(Filename);
// Note: Currently we do not support reading an archive from stdin.
if (Filename == "-" || aPath.isBitcodeFile()) {
std::auto_ptr<MemoryBuffer> Buffer(
MemoryBuffer::getFileOrSTDIN(Filename, &ErrorMessage));
Module *Result = 0;
if (Buffer.get())
Result = ParseBitcodeFile(Buffer.get(), Context, &ErrorMessage);
if (Result) {
DumpSymbolNamesFromModule(Result);
delete Result;
} else
errs() << ToolName << ": " << Filename << ": " << ErrorMessage << "\n";
} else if (aPath.isArchive()) {
std::string ErrMsg;
Archive* archive = Archive::OpenAndLoad(sys::Path(Filename), Context,
&ErrorMessage);
if (!archive)
errs() << ToolName << ": " << Filename << ": " << ErrorMessage << "\n";
std::vector<Module *> Modules;
if (archive->getAllModules(Modules, &ErrorMessage)) {
errs() << ToolName << ": " << Filename << ": " << ErrorMessage << "\n";
return;
}
MultipleFiles = true;
std::for_each (Modules.begin(), Modules.end(), DumpSymbolNamesFromModule);
} else {
errs() << ToolName << ": " << Filename << ": "
<< "unrecognizable file type\n";
return;
}
}
int main(int argc, char **argv) {
// Print a stack trace if we signal out.
sys::PrintStackTraceOnErrorSignal();
PrettyStackTraceProgram X(argc, argv);
llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
cl::ParseCommandLineOptions(argc, argv, "llvm symbol table dumper\n");
ToolName = argv[0];
if (BSDFormat) OutputFormat = bsd;
if (POSIXFormat) OutputFormat = posix;
switch (InputFilenames.size()) {
case 0: InputFilenames.push_back("-");
case 1: break;
default: MultipleFiles = true;
}
std::for_each(InputFilenames.begin(), InputFilenames.end(),
DumpSymbolNamesFromFile);
return 0;
}