path: root/lib/Target/PIC16/AsmPrinter/PIC16AsmPrinter.cpp

//===-- PIC16AsmPrinter.cpp - PIC16 LLVM assembly writer ------------------===//
//
//                     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 PIC16 assembly language.
//
//===----------------------------------------------------------------------===//

#include "PIC16ABINames.h"
#include "PIC16AsmPrinter.h"
#include "PIC16Section.h"
#include "PIC16MCAsmInfo.h"
#include "PIC16MachineFunctionInfo.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Module.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/SmallString.h"
#include <cstring>
using namespace llvm;

#include "PIC16GenAsmWriter.inc"

PIC16AsmPrinter::PIC16AsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
: AsmPrinter(TM, Streamer), DbgInfo(Streamer, TM.getMCAsmInfo()) {
  PTLI = static_cast<PIC16TargetLowering*>(TM.getTargetLowering());
  PMAI = static_cast<const PIC16MCAsmInfo*>(TM.getMCAsmInfo());
  PTOF = (PIC16TargetObjectFile *)&PTLI->getObjFileLowering();
}

void PIC16AsmPrinter::EmitInstruction(const MachineInstr *MI) {
  SmallString<128> Str;
  raw_svector_ostream OS(Str);
  printInstruction(MI, OS);
  
  OutStreamer.EmitRawText(OS.str());
}

static int getFunctionColor(const Function *F) {
  if (F->hasSection()) {
    std::string Sectn = F->getSection();
    std::string StrToFind = "Overlay=";
    std::string::size_type Pos = Sectn.find(StrToFind);

    // Retreive the color number if the key is found.
    if (Pos != std::string::npos) {
      Pos += StrToFind.length();
      std::string Color = "";
      char c = Sectn.at(Pos);
      // A Color can only consist of digits.
      while (c >= '0' && c<= '9') {
        Color.append(1,c);
        Pos++;
        if (Pos >= Sectn.length())
          break;
        c = Sectn.at(Pos);
      }
      return atoi(Color.c_str());
    }
  }

  // Color was not set for function, so return -1.
  return -1;
}

// Color the Auto section of the given function. 
void PIC16AsmPrinter::ColorAutoSection(const Function *F) {
  std::string SectionName = PAN::getAutosSectionName(CurrentFnSym->getName());
  PIC16Section* Section = PTOF->findPIC16Section(SectionName);
  if (Section != NULL) {
    int Color = getFunctionColor(F);
    if (Color >= 0)
      Section->setColor(Color);
  }
}


/// runOnMachineFunction - This emits the frame section, autos section and 
/// assembly for each instruction. Also takes care of function begin debug
/// directive and file begin debug directive (if required) for the function.
///
bool PIC16AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
  // This calls the base class function required to be called at beginning
  // of runOnMachineFunction.
  SetupMachineFunction(MF);

  // Put the color information from function to its auto section.
  const Function *F = MF.getFunction();
  ColorAutoSection(F);

  // Emit the function frame (args and temps).
  EmitFunctionFrame(MF);

  DbgInfo.BeginFunction(MF);

  // Now emit the instructions of function in its code section.
  const MCSection *fCodeSection = 
    getObjFileLowering().SectionForCode(CurrentFnSym->getName(), 
                                        PAN::isISR(F->getSection()));

  // Start the Code Section.
  OutStreamer.SwitchSection(fCodeSection);

  // Emit the frame address of the function at the beginning of code.
  OutStreamer.EmitRawText("\tretlw  low(" + 
                          Twine(PAN::getFrameLabel(CurrentFnSym->getName())) +
                          ")");
  OutStreamer.EmitRawText("\tretlw  high(" +
                          Twine(PAN::getFrameLabel(CurrentFnSym->getName())) +
                          ")");

  // Emit function start label.
  OutStreamer.EmitLabel(CurrentFnSym);

  DebugLoc CurDL;
  // Print out code for the function.
  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
       I != E; ++I) {

    // Print a label for the basic block.
    if (I != MF.begin())
      EmitBasicBlockStart(I);
    
    // Print a basic block.
    for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
         II != E; ++II) {
      // Emit the line directive if source line changed.
      DebugLoc DL = II->getDebugLoc();
      if (!DL.isUnknown() && DL != CurDL) {
        DbgInfo.ChangeDebugLoc(MF, DL);
        CurDL = DL;
      }
        
      // Print the assembly for the instruction.
      EmitInstruction(II);
    }
  }
  
  // Emit function end debug directives.
  DbgInfo.EndFunction(MF);

  return false;  // we didn't modify anything.
}


// printOperand - print operand of insn.
void PIC16AsmPrinter::printOperand(const MachineInstr *MI, int opNum,
                                   raw_ostream &O) {
  const MachineOperand &MO = MI->getOperand(opNum);
  const Function *F = MI->getParent()->getParent()->getFunction();

  switch (MO.getType()) {
    case MachineOperand::MO_Register:
      {
        // For indirect load/store insns, the fsr name is printed as INDF.
        std::string RegName = getRegisterName(MO.getReg());
        if ((MI->getOpcode() == PIC16::load_indirect) ||
            (MI->getOpcode() == PIC16::store_indirect))
          RegName.replace (0, 3, "INDF");
        O << RegName;
      }
      return;

    case MachineOperand::MO_Immediate:
      O << (int)MO.getImm();
      return;

    case MachineOperand::MO_GlobalAddress: {
      MCSymbol *Sym = Mang->getSymbol(MO.getGlobal());
      // FIXME: currently we do not have a memcpy def coming in the module
      // by any chance, as we do not link in those as .bc lib. So these calls
      // are always external and it is safe to emit an extern.
      if (PAN::isMemIntrinsic(Sym->getName()))
        LibcallDecls.insert(Sym->getName());

      O << *Sym;
      break;
    }
    case MachineOperand::MO_ExternalSymbol: {
       const char *Sname = MO.getSymbolName();
       std::string Printname = Sname;

      // Intrinsic stuff needs to be renamed if we are printing IL fn. 
      if (PAN::isIntrinsicStuff(Printname)) {
        if (PAN::isISR(F->getSection())) {
          Printname = PAN::Rename(Sname);
        }
        // Record these decls, we need to print them in asm as extern.
        LibcallDecls.insert(Printname);
      }

      O << Printname;
      break;
    }
    case MachineOperand::MO_MachineBasicBlock:
      O << *MO.getMBB()->getSymbol();
      return;

    default:
      llvm_unreachable(" Operand type not supported.");
  }
}

/// printCCOperand - Print the cond code operand.
///
void PIC16AsmPrinter::printCCOperand(const MachineInstr *MI, int opNum,
                                     raw_ostream &O) {
  int CC = (int)MI->getOperand(opNum).getImm();
  O << PIC16CondCodeToString((PIC16CC::CondCodes)CC);
}

/// printLibcallDecls - print the extern declarations for compiler 
/// intrinsics.
///
void PIC16AsmPrinter::printLibcallDecls() {
  // If no libcalls used, return.