path: root/lib/Target/PowerPC/PPCAsmPrinter.cpp

//===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly --------=//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains a printer that converts from our internal representation
// of machine-dependent LLVM code to PowerPC assembly language. This printer is
// the output mechanism used by `llc'.
//
// Documentation at http://developer.apple.com/documentation/DeveloperTools/
// Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
//
//===----------------------------------------------------------------------===//

#define DEBUG_TYPE "asmprinter"
#include "PPC.h"
#include "PPCPredicates.h"
#include "PPCTargetMachine.h"
#include "PPCSubtarget.h"
#include "llvm/Analysis/DebugInfo.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/ADT/SmallString.h"
#include "InstPrinter/PPCInstPrinter.h"
using namespace llvm;

// This option tells the asmprinter to use the new (experimental) MCInstPrinter
// path.
static cl::opt<bool> UseInstPrinter("enable-ppc-inst-printer",
                                    cl::ReallyHidden
                                    //, cl::init(true)
                                    );

namespace {
  class PPCAsmPrinter : public AsmPrinter {
  protected:
    DenseMap<MCSymbol*, MCSymbol*> TOC;
    const PPCSubtarget &Subtarget;
    uint64_t LabelID;
  public:
    explicit PPCAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
      : AsmPrinter(TM, Streamer),
        Subtarget(TM.getSubtarget<PPCSubtarget>()), LabelID(0) {}

    virtual const char *getPassName() const {
      return "PowerPC Assembly Printer";
    }

    unsigned enumRegToMachineReg(unsigned enumReg) {
      switch (enumReg) {
      default: llvm_unreachable("Unhandled register!");
      case PPC::CR0:  return  0;
      case PPC::CR1:  return  1;
      case PPC::CR2:  return  2;
      case PPC::CR3:  return  3;
      case PPC::CR4:  return  4;
      case PPC::CR5:  return  5;
      case PPC::CR6:  return  6;
      case PPC::CR7:  return  7;
      }
      llvm_unreachable(0);
    }

    /// printInstruction - This method is automatically generated by tablegen
    /// from the instruction set description.  This method returns true if the
    /// machine instruction was sufficiently described to print it, otherwise it
    /// returns false.
    void printInstruction(const MachineInstr *MI, raw_ostream &O);
    static const char *getRegisterName(unsigned RegNo);


    virtual void EmitInstruction(const MachineInstr *MI);
    void printOp(const MachineOperand &MO, raw_ostream &O);

    /// stripRegisterPrefix - This method strips the character prefix from a
    /// register name so that only the number is left.  Used by for linux asm.
    const char *stripRegisterPrefix(const char *RegName) {
      switch (RegName[0]) {
      case 'r':
      case 'f':
      case 'v': return RegName + 1;
      case 'c': if (RegName[1] == 'r') return RegName + 2;
      }

      return RegName;
    }

    /// printRegister - Print register according to target requirements.
    ///
    void printRegister(const MachineOperand &MO, bool R0AsZero, raw_ostream &O){
      unsigned RegNo = MO.getReg();
      assert(TargetRegisterInfo::isPhysicalRegister(RegNo) && "Not physreg??");

      // If we should use 0 for R0.
      if (R0AsZero && RegNo == PPC::R0) {
        O << "0";
        return;
      }

      const char *RegName = getRegisterName(RegNo);
      // Linux assembler (Others?) does not take register mnemonics.
      // FIXME - What about special registers used in mfspr/mtspr?
      if (!Subtarget.isDarwin()) RegName = stripRegisterPrefix(RegName);
      O << RegName;
    }

    void printOperand(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {