//===-- ARMTargetMachine.cpp - Define TargetMachine for ARM ---------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//
//===----------------------------------------------------------------------===//

#include "ARMTargetMachine.h"
#include "ARMTargetAsmInfo.h"
#include "ARMFrameInfo.h"
#include "ARM.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetMachineRegistry.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;

static cl::opt<bool> DisableLdStOpti("disable-arm-loadstore-opti", cl::Hidden,
                              cl::desc("Disable load store optimization pass"));
static cl::opt<bool> DisableIfConversion("disable-arm-if-conversion",cl::Hidden,
                              cl::desc("Disable if-conversion pass"));

/// ARMTargetMachineModule - Note that this is used on hosts that cannot link
/// in a library unless there are references into the library.  In particular,
/// it seems that it is not possible to get things to work on Win32 without
/// this.  Though it is unused, do not remove it.
extern "C" int ARMTargetMachineModule;
int ARMTargetMachineModule = 0;

// Register the target.
static RegisterTarget<ARMTargetMachine>   X("arm",   "ARM");
static RegisterTarget<ThumbTargetMachine> Y("thumb", "Thumb");

// No assembler printer by default
ARMTargetMachine::AsmPrinterCtorFn ARMTargetMachine::AsmPrinterCtor = 0;

/// ThumbTargetMachine - Create an Thumb architecture model.
///
unsigned ThumbTargetMachine::getJITMatchQuality() {
#if defined(__thumb__)
  return 10;
#endif
  return 0;
}

unsigned ThumbTargetMachine::getModuleMatchQuality(const Module &M) {
  std::string TT = M.getTargetTriple();
  // Match thumb-foo-bar, as well as things like thumbv5blah-*
  if (TT.size() >= 6 &&
      (TT.substr(0, 6) == "thumb-" || TT.substr(0, 6) == "thumbv"))
    return 20;

  // If the target triple is something non-thumb, we don't match.
  if (!TT.empty()) return 0;

  if (M.getEndianness()  == Module::LittleEndian &&
      M.getPointerSize() == Module::Pointer32)
    return 10;                                   // Weak match
  else if (M.getEndianness() != Module::AnyEndianness ||
           M.getPointerSize() != Module::AnyPointerSize)
    return 0;                                    // Match for some other target

  return getJITMatchQuality()/2;
}

ThumbTargetMachine::ThumbTargetMachine(const Module &M, const std::string &FS)
  : ARMTargetMachine(M, FS, true) {
}

/// TargetMachine ctor - Create an ARM architecture model.
///
ARMTargetMachine::ARMTargetMachine(const Module &M, const std::string &FS,
                                   bool isThumb)
  : Subtarget(M, FS, isThumb),
    DataLayout(Subtarget.isAPCS_ABI() ?
               // APCS ABI
          (isThumb ?
           std::string("e-p:32:32-f64:32:32-i64:32:32-"
                       "i16:16:32-i8:8:32-i1:8:32-a:0:32") :
           std::string("e-p:32:32-f64:32:32-i64:32:32")) :
               // AAPCS ABI
          (isThumb ?
           std::string("e-p:32:32-f64:64:64-i64:64:64-"
                       "i16:16:32-i8:8:32-i1:8:32-a:0:32") :
           std::string("e-p:32:32-f64:64:64-i64:64:64"))),
    InstrInfo(Subtarget),
    FrameInfo(Subtarget),
    JITInfo(),
    TLInfo(*this) {
  DefRelocModel = getRelocationModel();
}

unsigned ARMTargetMachine::getJITMatchQuality() {
#if defined(__arm__)
  return 10;
#endif
  return 0;
}

unsigned ARMTargetMachine::getModuleMatchQuality(const Module &M) {
  std::string TT = M.getTargetTriple();
  // Match arm-foo-bar, as well as things like armv5blah-*
  if (TT.size() >= 4 &&
      (TT.substr(0, 4) == "arm-" || TT.substr(0, 4) == "armv"))
    return 20;
  // If the target triple is something non-arm, we don't match.
  if (!TT.empty()) return 0;

  if (M.getEndianness()  == Module::LittleEndian &&
      M.getPointerSize() == Module::Pointer32)
    return 10;                                   // Weak match
  else if (M.getEndianness() != Module::AnyEndianness ||
           M.getPointerSize() != Module::AnyPointerSize)
    return 0;                                    // Match for some other target

  return getJITMatchQuality()/2;
}


const TargetAsmInfo *ARMTargetMachine::createTargetAsmInfo() const {
  switch (Subtarget.TargetType) {
   case ARMSubtarget::isDarwin:
    return new ARMDarwinTargetAsmInfo(*this);
   case ARMSubtarget::isELF:
    return new ARMELFTargetAsmInfo(*this);
   default:
    return new ARMGenericTargetAsmInfo(*this);
  }
}


// Pass Pipeline Configuration
bool ARMTargetMachine::addInstSelector(PassManagerBase &PM, unsigned OptLevel) {
  PM.add(createARMISelDag(*this));
  return false;
}

bool ARMTargetMachine::addPreEmitPass(PassManagerBase &PM, unsigned OptLevel) {
  // FIXME: temporarily disabling load / store optimization pass for Thumb mode.
  if (OptLevel != 0 && !DisableLdStOpti && !Subtarget.isThumb())
    PM.add(createARMLoadStoreOptimizationPass());

  if (OptLevel != 0 && !DisableIfConversion && !Subtarget.isThumb())
    PM.add(createIfConverterPass());

  PM.add(createARMConstantIslandPass());
  return true;
}

bool ARMTargetMachine::addAssemblyEmitter(PassManagerBase &PM,
                                          unsigned OptLevel,
                                          bool Verbose,
                                          raw_ostream &Out) {
  // Output assembly language.
  assert(AsmPrinterCtor && "AsmPrinter was not linked in");
  if (AsmPrinterCtor)
    PM.add(AsmPrinterCtor(Out, *this, OptLevel, Verbose));

  return false;
}


bool ARMTargetMachine::addCodeEmitter(PassManagerBase &PM, unsigned OptLevel,
                                      bool DumpAsm, MachineCodeEmitter &MCE) {
  // FIXME: Move this to TargetJITInfo!
  if (DefRelocModel == Reloc::Default)
    setRelocationModel(Reloc::Static);

  // Machine code emitter pass for ARM.
  PM.add(createARMCodeEmitterPass(*this, MCE));
  if (DumpAsm) {
    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
    if (AsmPrinterCtor)
      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
  }

  return false;
}

bool ARMTargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
                                            unsigned OptLevel,
                                            bool DumpAsm,
                                            MachineCodeEmitter &MCE) {
  // Machine code emitter pass for ARM.
  PM.add(createARMCodeEmitterPass(*this, MCE));
  if (DumpAsm) {
    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
    if (AsmPrinterCtor)
      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
  }

  return false;
}