llvm/tools/llc/llc.cpp
Eric Christopher 04bcc11905 Move DataLayout back to the TargetMachine from TargetSubtargetInfo
derived classes.

Since global data alignment, layout, and mangling is often based on the
DataLayout, move it to the TargetMachine. This ensures that global
data is going to be layed out and mangled consistently if the subtarget
changes on a per function basis. Prior to this all targets(*) have
had subtarget dependent code moved out and onto the TargetMachine.

*One target hasn't been migrated as part of this change: R600. The
R600 port has, as a subtarget feature, the size of pointers and
this affects global data layout. I've currently hacked in a FIXME
to enable progress, but the port needs to be updated to either pass
the 64-bitness to the TargetMachine, or fix the DataLayout to
avoid subtarget dependent features.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227113 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 19:03:15 +00:00

358 lines
12 KiB
C++

//===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is the llc code generator driver. It provides a convenient
// command-line interface for generating native assembly-language code
// or C code, given LLVM bitcode.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/CodeGen/CommandFlags.h"
#include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
#include "llvm/CodeGen/LinkAllCodegenComponents.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IRReader/IRReader.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Pass.h"
#include "llvm/PassManager.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/PluginLoader.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"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetSubtargetInfo.h"
#include <memory>
using namespace llvm;
// General options for llc. Other pass-specific options are specified
// within the corresponding llc passes, and target-specific options
// and back-end code generation options are specified with the target machine.
//
static cl::opt<std::string>
InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
static cl::opt<unsigned>
TimeCompilations("time-compilations", cl::Hidden, cl::init(1u),
cl::value_desc("N"),
cl::desc("Repeat compilation N times for timing"));
static cl::opt<bool>
NoIntegratedAssembler("no-integrated-as", cl::Hidden,
cl::desc("Disable integrated assembler"));
// Determine optimization level.
static cl::opt<char>
OptLevel("O",
cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
"(default = '-O2')"),
cl::Prefix,
cl::ZeroOrMore,
cl::init(' '));
static cl::opt<std::string>
TargetTriple("mtriple", cl::desc("Override target triple for module"));
static cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
cl::desc("Do not verify input module"));
static cl::opt<bool> DisableSimplifyLibCalls("disable-simplify-libcalls",
cl::desc("Disable simplify-libcalls"));
static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden,
cl::desc("Show encoding in .s output"));
static cl::opt<bool> EnableDwarfDirectory(
"enable-dwarf-directory", cl::Hidden,
cl::desc("Use .file directives with an explicit directory."));
static cl::opt<bool> AsmVerbose("asm-verbose",
cl::desc("Add comments to directives."),
cl::init(true));
static int compileModule(char **, LLVMContext &);
static std::unique_ptr<tool_output_file>
GetOutputStream(const char *TargetName, Triple::OSType OS,
const char *ProgName) {
// If we don't yet have an output filename, make one.
if (OutputFilename.empty()) {
if (InputFilename == "-")
OutputFilename = "-";
else {
// If InputFilename ends in .bc or .ll, remove it.
StringRef IFN = InputFilename;
if (IFN.endswith(".bc") || IFN.endswith(".ll"))
OutputFilename = IFN.drop_back(3);
else
OutputFilename = IFN;
switch (FileType) {
case TargetMachine::CGFT_AssemblyFile:
if (TargetName[0] == 'c') {
if (TargetName[1] == 0)
OutputFilename += ".cbe.c";
else if (TargetName[1] == 'p' && TargetName[2] == 'p')
OutputFilename += ".cpp";
else
OutputFilename += ".s";
} else
OutputFilename += ".s";
break;
case TargetMachine::CGFT_ObjectFile:
if (OS == Triple::Win32)
OutputFilename += ".obj";
else
OutputFilename += ".o";
break;
case TargetMachine::CGFT_Null:
OutputFilename += ".null";
break;
}
}
}
// Decide if we need "binary" output.
bool Binary = false;
switch (FileType) {
case TargetMachine::CGFT_AssemblyFile:
break;
case TargetMachine::CGFT_ObjectFile:
case TargetMachine::CGFT_Null:
Binary = true;
break;
}
// Open the file.
std::error_code EC;
sys::fs::OpenFlags OpenFlags = sys::fs::F_None;
if (!Binary)
OpenFlags |= sys::fs::F_Text;
auto FDOut = llvm::make_unique<tool_output_file>(OutputFilename, EC,
OpenFlags);
if (EC) {
errs() << EC.message() << '\n';
return nullptr;
}
return FDOut;
}
// main - Entry point for the llc compiler.
//
int main(int argc, char **argv) {
sys::PrintStackTraceOnErrorSignal();
PrettyStackTraceProgram X(argc, argv);
// Enable debug stream buffering.
EnableDebugBuffering = true;
LLVMContext &Context = getGlobalContext();
llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
// Initialize targets first, so that --version shows registered targets.
InitializeAllTargets();
InitializeAllTargetMCs();
InitializeAllAsmPrinters();
InitializeAllAsmParsers();
// Initialize codegen and IR passes used by llc so that the -print-after,
// -print-before, and -stop-after options work.
PassRegistry *Registry = PassRegistry::getPassRegistry();
initializeCore(*Registry);
initializeCodeGen(*Registry);
initializeLoopStrengthReducePass(*Registry);
initializeLowerIntrinsicsPass(*Registry);
initializeUnreachableBlockElimPass(*Registry);
// Register the target printer for --version.
cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
// Compile the module TimeCompilations times to give better compile time
// metrics.
for (unsigned I = TimeCompilations; I; --I)
if (int RetVal = compileModule(argv, Context))
return RetVal;
return 0;
}
static int compileModule(char **argv, LLVMContext &Context) {
// Load the module to be compiled...
SMDiagnostic Err;
std::unique_ptr<Module> M;
Triple TheTriple;
bool SkipModule = MCPU == "help" ||
(!MAttrs.empty() && MAttrs.front() == "help");
// If user asked for the 'native' CPU, autodetect here. If autodection fails,
// this will set the CPU to an empty string which tells the target to
// pick a basic default.
if (MCPU == "native")
MCPU = sys::getHostCPUName();
// If user just wants to list available options, skip module loading
if (!SkipModule) {
M = parseIRFile(InputFilename, Err, Context);
if (!M) {
Err.print(argv[0], errs());
return 1;
}
// If we are supposed to override the target triple, do so now.
if (!TargetTriple.empty())
M->setTargetTriple(Triple::normalize(TargetTriple));
TheTriple = Triple(M->getTargetTriple());
} else {
TheTriple = Triple(Triple::normalize(TargetTriple));
}
if (TheTriple.getTriple().empty())
TheTriple.setTriple(sys::getDefaultTargetTriple());
// Get the target specific parser.
std::string Error;
const Target *TheTarget = TargetRegistry::lookupTarget(MArch, TheTriple,
Error);
if (!TheTarget) {
errs() << argv[0] << ": " << Error;
return 1;
}
// 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();
}
CodeGenOpt::Level OLvl = CodeGenOpt::Default;
switch (OptLevel) {
default:
errs() << argv[0] << ": invalid optimization level.\n";
return 1;
case ' ': break;
case '0': OLvl = CodeGenOpt::None; break;
case '1': OLvl = CodeGenOpt::Less; break;
case '2': OLvl = CodeGenOpt::Default; break;
case '3': OLvl = CodeGenOpt::Aggressive; break;
}
TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
Options.DisableIntegratedAS = NoIntegratedAssembler;
Options.MCOptions.ShowMCEncoding = ShowMCEncoding;
Options.MCOptions.MCUseDwarfDirectory = EnableDwarfDirectory;
Options.MCOptions.AsmVerbose = AsmVerbose;
std::unique_ptr<TargetMachine> Target(
TheTarget->createTargetMachine(TheTriple.getTriple(), MCPU, FeaturesStr,
Options, RelocModel, CMModel, OLvl));
assert(Target && "Could not allocate target machine!");
// If we don't have a module then just exit now. We do this down
// here since the CPU/Feature help is underneath the target machine
// creation.
if (SkipModule)
return 0;
assert(M && "Should have exited if we didn't have a module!");
if (GenerateSoftFloatCalls)
FloatABIForCalls = FloatABI::Soft;
// Figure out where we are going to send the output.
std::unique_ptr<tool_output_file> Out =
GetOutputStream(TheTarget->getName(), TheTriple.getOS(), argv[0]);
if (!Out) return 1;
// Build up all of the passes that we want to do to the module.
PassManager PM;
// Add an appropriate TargetLibraryInfo pass for the module's triple.
TargetLibraryInfoImpl TLII(Triple(M->getTargetTriple()));
// The -disable-simplify-libcalls flag actually disables all builtin optzns.
if (DisableSimplifyLibCalls)
TLII.disableAllFunctions();
PM.add(new TargetLibraryInfoWrapperPass(TLII));
// Add the target data from the target machine, if it exists, or the module.
if (const DataLayout *DL = Target->getDataLayout())
M->setDataLayout(DL);
PM.add(new DataLayoutPass());
if (RelaxAll.getNumOccurrences() > 0 &&
FileType != TargetMachine::CGFT_ObjectFile)
errs() << argv[0]
<< ": warning: ignoring -mc-relax-all because filetype != obj";
{
formatted_raw_ostream FOS(Out->os());
AnalysisID StartAfterID = nullptr;
AnalysisID StopAfterID = nullptr;
const PassRegistry *PR = PassRegistry::getPassRegistry();
if (!StartAfter.empty()) {
const PassInfo *PI = PR->getPassInfo(StartAfter);
if (!PI) {
errs() << argv[0] << ": start-after pass is not registered.\n";
return 1;
}
StartAfterID = PI->getTypeInfo();
}
if (!StopAfter.empty()) {
const PassInfo *PI = PR->getPassInfo(StopAfter);
if (!PI) {
errs() << argv[0] << ": stop-after pass is not registered.\n";
return 1;
}
StopAfterID = PI->getTypeInfo();
}
// Ask the target to add backend passes as necessary.
if (Target->addPassesToEmitFile(PM, FOS, FileType, NoVerify,
StartAfterID, StopAfterID)) {
errs() << argv[0] << ": target does not support generation of this"
<< " file type!\n";
return 1;
}
// Before executing passes, print the final values of the LLVM options.
cl::PrintOptionValues();
PM.run(*M);
}
// Declare success.
Out->keep();
return 0;
}