llvm-6502/tools/llvm-mc/llvm-mc.cpp
Rafael Espindola d80979b25d Don't declare all text sections at the start of the .s
The code this patch removes was there to make sure the text sections went
before the dwarf sections. That is necessary because MachO uses offsets
relative to the start of the file, so adding a section can change relaxations.

The dwarf sections were being printed at the start just to produce symbols
pointing at the start of those sections.

The underlying issue was fixed in r231898. The dwarf sections are now printed
when they are about to be used, which is after we printed the text sections.

To make sure we don't regress, the patch makes the MachO streamer assert
if CodeGen puts anything unexpected after the DWARF sections.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232842 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-20 20:00:01 +00:00

508 lines
18 KiB
C++

//===-- llvm-mc.cpp - Machine Code Hacking Driver -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This utility is a simple driver that allows command line hacking on machine
// code.
//
//===----------------------------------------------------------------------===//
#include "Disassembler.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCInstPrinter.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/MC/MCParser/AsmLexer.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCTargetAsmParser.h"
#include "llvm/MC/MCTargetOptionsCommandFlags.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compression.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/Signals.h"
#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/TargetSelect.h"
#include "llvm/Support/ToolOutputFile.h"
using namespace llvm;
static cl::opt<std::string>
InputFilename(cl::Positional, cl::desc("<input file>"), cl::init("-"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Output filename"),
cl::value_desc("filename"));
static cl::opt<bool>
ShowEncoding("show-encoding", cl::desc("Show instruction encodings"));
static cl::opt<bool>
CompressDebugSections("compress-debug-sections",
cl::desc("Compress DWARF debug sections"));
static cl::opt<bool>
ShowInst("show-inst", cl::desc("Show internal instruction representation"));
static cl::opt<bool>
ShowInstOperands("show-inst-operands",
cl::desc("Show instructions operands as parsed"));
static cl::opt<unsigned>
OutputAsmVariant("output-asm-variant",
cl::desc("Syntax variant to use for output printing"));
static cl::opt<bool>
PrintImmHex("print-imm-hex", cl::init(false),
cl::desc("Prefer hex format for immediate values"));
enum OutputFileType {
OFT_Null,
OFT_AssemblyFile,
OFT_ObjectFile
};
static cl::opt<OutputFileType>
FileType("filetype", cl::init(OFT_AssemblyFile),
cl::desc("Choose an output file type:"),
cl::values(
clEnumValN(OFT_AssemblyFile, "asm",
"Emit an assembly ('.s') file"),
clEnumValN(OFT_Null, "null",
"Don't emit anything (for timing purposes)"),
clEnumValN(OFT_ObjectFile, "obj",
"Emit a native object ('.o') file"),
clEnumValEnd));
static cl::list<std::string>
IncludeDirs("I", cl::desc("Directory of include files"),
cl::value_desc("directory"), cl::Prefix);
static cl::opt<std::string>
ArchName("arch", cl::desc("Target arch to assemble for, "
"see -version for available targets"));
static cl::opt<std::string>
TripleName("triple", cl::desc("Target triple to assemble for, "
"see -version for available targets"));
static cl::opt<std::string>
MCPU("mcpu",
cl::desc("Target a specific cpu type (-mcpu=help for details)"),
cl::value_desc("cpu-name"),
cl::init(""));
static cl::list<std::string>
MAttrs("mattr",
cl::CommaSeparated,
cl::desc("Target specific attributes (-mattr=help for details)"),
cl::value_desc("a1,+a2,-a3,..."));
static cl::opt<Reloc::Model>
RelocModel("relocation-model",
cl::desc("Choose relocation model"),
cl::init(Reloc::Default),
cl::values(
clEnumValN(Reloc::Default, "default",
"Target default relocation model"),
clEnumValN(Reloc::Static, "static",
"Non-relocatable code"),
clEnumValN(Reloc::PIC_, "pic",
"Fully relocatable, position independent code"),
clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
"Relocatable external references, non-relocatable code"),
clEnumValEnd));
static cl::opt<llvm::CodeModel::Model>
CMModel("code-model",
cl::desc("Choose code model"),
cl::init(CodeModel::Default),
cl::values(clEnumValN(CodeModel::Default, "default",
"Target default code model"),
clEnumValN(CodeModel::Small, "small",
"Small code model"),
clEnumValN(CodeModel::Kernel, "kernel",
"Kernel code model"),
clEnumValN(CodeModel::Medium, "medium",
"Medium code model"),
clEnumValN(CodeModel::Large, "large",
"Large code model"),
clEnumValEnd));
static cl::opt<bool>
NoInitialTextSection("n", cl::desc("Don't assume assembly file starts "
"in the text section"));
static cl::opt<bool>
GenDwarfForAssembly("g", cl::desc("Generate dwarf debugging info for assembly "
"source files"));
static cl::opt<std::string>
DebugCompilationDir("fdebug-compilation-dir",
cl::desc("Specifies the debug info's compilation dir"));
static cl::opt<std::string>
MainFileName("main-file-name",
cl::desc("Specifies the name we should consider the input file"));
static cl::opt<bool> SaveTempLabels("save-temp-labels",
cl::desc("Don't discard temporary labels"));
static cl::opt<bool> NoExecStack("no-exec-stack",
cl::desc("File doesn't need an exec stack"));
enum ActionType {
AC_AsLex,
AC_Assemble,
AC_Disassemble,
AC_MDisassemble,
};
static cl::opt<ActionType>
Action(cl::desc("Action to perform:"),
cl::init(AC_Assemble),
cl::values(clEnumValN(AC_AsLex, "as-lex",
"Lex tokens from a .s file"),
clEnumValN(AC_Assemble, "assemble",
"Assemble a .s file (default)"),
clEnumValN(AC_Disassemble, "disassemble",
"Disassemble strings of hex bytes"),
clEnumValN(AC_MDisassemble, "mdis",
"Marked up disassembly of strings of hex bytes"),
clEnumValEnd));
static const Target *GetTarget(const char *ProgName) {
// Figure out the target triple.
if (TripleName.empty())
TripleName = sys::getDefaultTargetTriple();
Triple TheTriple(Triple::normalize(TripleName));
// Get the target specific parser.
std::string Error;
const Target *TheTarget = TargetRegistry::lookupTarget(ArchName, TheTriple,
Error);
if (!TheTarget) {
errs() << ProgName << ": " << Error;
return nullptr;
}
// Update the triple name and return the found target.
TripleName = TheTriple.getTriple();
return TheTarget;
}
static std::unique_ptr<tool_output_file> GetOutputStream() {
if (OutputFilename == "")
OutputFilename = "-";
std::error_code EC;
auto Out = llvm::make_unique<tool_output_file>(OutputFilename, EC,
sys::fs::F_None);
if (EC) {
errs() << EC.message() << '\n';
return nullptr;
}
return Out;
}
static std::string DwarfDebugFlags;
static void setDwarfDebugFlags(int argc, char **argv) {
if (!getenv("RC_DEBUG_OPTIONS"))
return;
for (int i = 0; i < argc; i++) {
DwarfDebugFlags += argv[i];
if (i + 1 < argc)
DwarfDebugFlags += " ";
}
}
static std::string DwarfDebugProducer;
static void setDwarfDebugProducer(void) {
if(!getenv("DEBUG_PRODUCER"))
return;
DwarfDebugProducer += getenv("DEBUG_PRODUCER");
}
static int AsLexInput(SourceMgr &SrcMgr, MCAsmInfo &MAI,
raw_ostream &OS) {
AsmLexer Lexer(MAI);
Lexer.setBuffer(SrcMgr.getMemoryBuffer(SrcMgr.getMainFileID())->getBuffer());
bool Error = false;
while (Lexer.Lex().isNot(AsmToken::Eof)) {
AsmToken Tok = Lexer.getTok();
switch (Tok.getKind()) {
default:
SrcMgr.PrintMessage(Lexer.getLoc(), SourceMgr::DK_Warning,
"unknown token");
Error = true;
break;
case AsmToken::Error:
Error = true; // error already printed.
break;
case AsmToken::Identifier:
OS << "identifier: " << Lexer.getTok().getString();
break;
case AsmToken::Integer:
OS << "int: " << Lexer.getTok().getString();
break;
case AsmToken::Real:
OS << "real: " << Lexer.getTok().getString();
break;
case AsmToken::String:
OS << "string: " << Lexer.getTok().getString();
break;
case AsmToken::Amp: OS << "Amp"; break;
case AsmToken::AmpAmp: OS << "AmpAmp"; break;
case AsmToken::At: OS << "At"; break;
case AsmToken::Caret: OS << "Caret"; break;
case AsmToken::Colon: OS << "Colon"; break;
case AsmToken::Comma: OS << "Comma"; break;
case AsmToken::Dollar: OS << "Dollar"; break;
case AsmToken::Dot: OS << "Dot"; break;
case AsmToken::EndOfStatement: OS << "EndOfStatement"; break;
case AsmToken::Eof: OS << "Eof"; break;
case AsmToken::Equal: OS << "Equal"; break;
case AsmToken::EqualEqual: OS << "EqualEqual"; break;
case AsmToken::Exclaim: OS << "Exclaim"; break;
case AsmToken::ExclaimEqual: OS << "ExclaimEqual"; break;
case AsmToken::Greater: OS << "Greater"; break;
case AsmToken::GreaterEqual: OS << "GreaterEqual"; break;
case AsmToken::GreaterGreater: OS << "GreaterGreater"; break;
case AsmToken::Hash: OS << "Hash"; break;
case AsmToken::LBrac: OS << "LBrac"; break;
case AsmToken::LCurly: OS << "LCurly"; break;
case AsmToken::LParen: OS << "LParen"; break;
case AsmToken::Less: OS << "Less"; break;
case AsmToken::LessEqual: OS << "LessEqual"; break;
case AsmToken::LessGreater: OS << "LessGreater"; break;
case AsmToken::LessLess: OS << "LessLess"; break;
case AsmToken::Minus: OS << "Minus"; break;
case AsmToken::Percent: OS << "Percent"; break;
case AsmToken::Pipe: OS << "Pipe"; break;
case AsmToken::PipePipe: OS << "PipePipe"; break;
case AsmToken::Plus: OS << "Plus"; break;
case AsmToken::RBrac: OS << "RBrac"; break;
case AsmToken::RCurly: OS << "RCurly"; break;
case AsmToken::RParen: OS << "RParen"; break;
case AsmToken::Slash: OS << "Slash"; break;
case AsmToken::Star: OS << "Star"; break;
case AsmToken::Tilde: OS << "Tilde"; break;
}
// Print the token string.
OS << " (\"";
OS.write_escaped(Tok.getString());
OS << "\")\n";
}
return Error;
}
static int AssembleInput(const char *ProgName, const Target *TheTarget,
SourceMgr &SrcMgr, MCContext &Ctx, MCStreamer &Str,
MCAsmInfo &MAI, MCSubtargetInfo &STI,
MCInstrInfo &MCII, MCTargetOptions &MCOptions) {
std::unique_ptr<MCAsmParser> Parser(
createMCAsmParser(SrcMgr, Ctx, Str, MAI));
std::unique_ptr<MCTargetAsmParser> TAP(
TheTarget->createMCAsmParser(STI, *Parser, MCII, MCOptions));
if (!TAP) {
errs() << ProgName
<< ": error: this target does not support assembly parsing.\n";
return 1;
}
Parser->setShowParsedOperands(ShowInstOperands);
Parser->setTargetParser(*TAP);
int Res = Parser->Run(NoInitialTextSection);
return Res;
}
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.
// Initialize targets and assembly printers/parsers.
llvm::InitializeAllTargetInfos();
llvm::InitializeAllTargetMCs();
llvm::InitializeAllAsmParsers();
llvm::InitializeAllDisassemblers();
// Register the target printer for --version.
cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
cl::ParseCommandLineOptions(argc, argv, "llvm machine code playground\n");
MCTargetOptions MCOptions = InitMCTargetOptionsFromFlags();
TripleName = Triple::normalize(TripleName);
Triple TheTriple(TripleName);
setDwarfDebugFlags(argc, argv);
setDwarfDebugProducer();
const char *ProgName = argv[0];
const Target *TheTarget = GetTarget(ProgName);
if (!TheTarget)
return 1;
ErrorOr<std::unique_ptr<MemoryBuffer>> BufferPtr =
MemoryBuffer::getFileOrSTDIN(InputFilename);
if (std::error_code EC = BufferPtr.getError()) {
errs() << ProgName << ": " << EC.message() << '\n';
return 1;
}
MemoryBuffer *Buffer = BufferPtr->get();
SourceMgr SrcMgr;
// Tell SrcMgr about this buffer, which is what the parser will pick up.
SrcMgr.AddNewSourceBuffer(std::move(*BufferPtr), SMLoc());
// Record the location of the include directories so that the lexer can find
// it later.
SrcMgr.setIncludeDirs(IncludeDirs);
std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
assert(MRI && "Unable to create target register info!");
std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TripleName));
assert(MAI && "Unable to create target asm info!");
if (CompressDebugSections) {
if (!zlib::isAvailable()) {
errs() << ProgName
<< ": build tools with zlib to enable -compress-debug-sections";
return 1;
}
MAI->setCompressDebugSections(true);
}
// FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
// MCObjectFileInfo needs a MCContext reference in order to initialize itself.
MCObjectFileInfo MOFI;
MCContext Ctx(MAI.get(), MRI.get(), &MOFI, &SrcMgr);
MOFI.InitMCObjectFileInfo(TripleName, RelocModel, CMModel, Ctx);
if (SaveTempLabels)
Ctx.setAllowTemporaryLabels(false);
Ctx.setGenDwarfForAssembly(GenDwarfForAssembly);
// Default to 4 for dwarf version.
unsigned DwarfVersion = MCOptions.DwarfVersion ? MCOptions.DwarfVersion : 4;
if (DwarfVersion < 2 || DwarfVersion > 4) {
errs() << ProgName << ": Dwarf version " << DwarfVersion
<< " is not supported." << '\n';
return 1;
}
Ctx.setDwarfVersion(DwarfVersion);
if (!DwarfDebugFlags.empty())
Ctx.setDwarfDebugFlags(StringRef(DwarfDebugFlags));
if (!DwarfDebugProducer.empty())
Ctx.setDwarfDebugProducer(StringRef(DwarfDebugProducer));
if (!DebugCompilationDir.empty())
Ctx.setCompilationDir(DebugCompilationDir);
if (!MainFileName.empty())
Ctx.setMainFileName(MainFileName);
// Package up features to be passed to target/subtarget
std::string FeaturesStr;
if (MAttrs.size()) {
SubtargetFeatures Features;
for (unsigned i = 0; i != MAttrs.size(); ++i)
Features.AddFeature(MAttrs[i]);
FeaturesStr = Features.getString();
}
std::unique_ptr<tool_output_file> Out = GetOutputStream();
if (!Out)
return 1;
formatted_raw_ostream FOS(Out->os());
std::unique_ptr<MCStreamer> Str;
std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
std::unique_ptr<MCSubtargetInfo> STI(
TheTarget->createMCSubtargetInfo(TripleName, MCPU, FeaturesStr));
MCInstPrinter *IP = nullptr;
if (FileType == OFT_AssemblyFile) {
IP =
TheTarget->createMCInstPrinter(OutputAsmVariant, *MAI, *MCII, *MRI, *STI);
// Set the display preference for hex vs. decimal immediates.
IP->setPrintImmHex(PrintImmHex);
// Set up the AsmStreamer.
MCCodeEmitter *CE = nullptr;
MCAsmBackend *MAB = nullptr;
if (ShowEncoding) {
CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx);
MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, MCPU);
}
Str.reset(TheTarget->createAsmStreamer(Ctx, FOS, /*asmverbose*/ true,
/*useDwarfDirectory*/ true, IP, CE,
MAB, ShowInst));
} else if (FileType == OFT_Null) {
Str.reset(TheTarget->createNullStreamer(Ctx));
} else {
assert(FileType == OFT_ObjectFile && "Invalid file type!");
MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx);
MCAsmBackend *MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, MCPU);
Str.reset(TheTarget->createMCObjectStreamer(TheTriple, Ctx, *MAB, FOS, CE,
*STI, RelaxAll,
/*DWARFMustBeAtTheEnd*/ false));
if (NoExecStack)
Str->InitSections(true);
}
int Res = 1;
bool disassemble = false;
switch (Action) {
case AC_AsLex:
Res = AsLexInput(SrcMgr, *MAI, Out->os());
break;
case AC_Assemble:
Res = AssembleInput(ProgName, TheTarget, SrcMgr, Ctx, *Str, *MAI, *STI,
*MCII, MCOptions);
break;
case AC_MDisassemble:
assert(IP && "Expected assembly output");
IP->setUseMarkup(1);
disassemble = true;
break;
case AC_Disassemble:
disassemble = true;
break;
}
if (disassemble)
Res = Disassembler::disassemble(*TheTarget, TripleName, *STI, *Str,
*Buffer, SrcMgr, Out->os());
// Keep output if no errors.
if (Res == 0) Out->keep();
return Res;
}