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//===-- MipsInstPrinter.cpp - Convert Mips MCInst to assembly syntax ------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This class prints an Mips MCInst to a .s file.
//
//===----------------------------------------------------------------------===//

#define DEBUG_TYPE "asm-printer"
#include "MipsInstPrinter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/StringExtras.h"
using namespace llvm;

#define GET_INSTRUCTION_NAME
#include "MipsGenAsmWriter.inc"

const char* Mips::MipsFCCToString(Mips::CondCode CC) {
  switch (CC) {
  case FCOND_F:
  case FCOND_T:   return "f";
  case FCOND_UN:
  case FCOND_OR:  return "un";
  case FCOND_OEQ:
  case FCOND_UNE: return "eq";
  case FCOND_UEQ:
  case FCOND_ONE: return "ueq";
  case FCOND_OLT:
  case FCOND_UGE: return "olt";
  case FCOND_ULT:
  case FCOND_OGE: return "ult";
  case FCOND_OLE:
  case FCOND_UGT: return "ole";
  case FCOND_ULE:
  case FCOND_OGT: return "ule";
  case FCOND_SF:
  case FCOND_ST:  return "sf";
  case FCOND_NGLE:
  case FCOND_GLE: return "ngle";
  case FCOND_SEQ:
  case FCOND_SNE: return "seq";
  case FCOND_NGL:
  case FCOND_GL:  return "ngl";
  case FCOND_LT:
  case FCOND_NLT: return "lt";
  case FCOND_NGE:
  case FCOND_GE:  return "nge";
  case FCOND_LE:
  case FCOND_NLE: return "le";
  case FCOND_NGT:
  case FCOND_GT:  return "ngt";
  }
  llvm_unreachable("Impossible condition code!");
}

StringRef MipsInstPrinter::getOpcodeName(unsigned Opcode) const {
  return getInstructionName(Opcode);
}

void MipsInstPrinter::printRegName(raw_ostream &OS, unsigned RegNo) const {
  OS << '$' << LowercaseString(getRegisterName(RegNo));
}

void MipsInstPrinter::printInst(const MCInst *MI, raw_ostream &O,
                                StringRef Annot) {
  printInstruction(MI, O);
  printAnnotation(O, Annot);
}

void MipsInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
                                   raw_ostream &O) {
  const MCOperand &Op = MI->getOperand(OpNo);
  if (Op.isReg()) {
    printRegName(O, Op.getReg());
    return;
  }
  
  if (Op.isImm()) {
    O << Op.getImm();
    return;
  }
  
  assert(Op.isExpr() && "unknown operand kind in printOperand");
  O << *Op.getExpr();
}

void MipsInstPrinter::printUnsignedImm(const MCInst *MI, int opNum,
                                       raw_ostream &O) {
  const MCOperand &MO = MI->getOperand(opNum);
  if (MO.isImm())
    O << (unsigned short int)MO.getImm();
  else
    printOperand(MI, opNum, O);
}

void MipsInstPrinter::
printMemOperand(const MCInst *MI, int opNum, raw_ostream &O) {
  // Load/Store memory operands -- imm($reg)
  // If PIC target the target is loaded as the
  // pattern lw $25,%call16($28)
  printOperand(MI, opNum+1, O);
  O << "(";
  printOperand(MI, opNum, O);
  O << ")";
}

void MipsInstPrinter::
printMemOperandEA(const MCInst *MI, int opNum, raw_ostream &O) {
  // when using stack locations for not load/store instructions
  // print the same way as all normal 3 operand instructions.
  printOperand(MI, opNum, O);
  O << ", ";
  printOperand(MI, opNum+1, O);
  return;
}

void MipsInstPrinter::
printFCCOperand(const MCInst *MI, int opNum, raw_ostream &O) {
  const MCOperand& MO = MI->getOperand(opNum);
  O << MipsFCCToString((Mips::CondCode)MO.getImm());
}