#ifndef _EMIT_H
#define _EMIT_H

/*  emit.h
 *    by CMB 10/04
 *     Some useful utility functions and class for code generation.
 *
 *    Detailed documentation appears next to headers and class def.
 */

#include <iostream>
#include <string>
using namespace std;

/* emit funcs
 *   Overloaded function to format MIPS instructions
 *      Takes 2, 3, or 4 strings
 *   Puts the instruction all on one line, with a tab before and after
 *      the operation, and ends the instruction with a newline.
 *
 */
void emit(ostream & o, const string &opcode, 
	  const string &operand);
void emit(ostream & o, const string &opcode, 
	  const string &op1, 
	  const string &op2);
void emit(ostream & o, const string &opcode, 
	  const string &op1, 
	  const string &op2, 
	  const string &op3);


// emitLabelDef emits a label not indented, followed by ":"
//   on a line by itself
void emitLabelDef(ostream & o, const string &label);


// ind(offset,reg) generates the string: offset(reg)
// for MIPS indexed addressing.
// Normally you would then pass the result of ind to one of the emit functions
string ind(int offset, const string &reg);

// imm(num) generates the string version of num
// for MIPS immediate addressing
// Normally you would then pass the result of ind to one of the emit functions
// Note: since emit functions only take strings, this is an easy way
//    to pass an int to one of those functions.
string imm(int num);



/* NameGenerator
 *
 * Generates unique names with a given prefix.
 *    Each a call to gen() returns the next unused name.
 *   
 * E.g., if the prefix is "t", the names generated are "t0", "t1", "t2", etc.
 *  For this example, the code is:
 *
 * NameGenerator tgen("t");
 *
 * cout << tgen.gen();  // prints t0
 * cout << tgen.gen();  // prints t1
 * cout << tgen.gen();  // prints t2
 *
 */
class NameGenerator {
 public:
  NameGenerator(const string &prefix);

  string gen();

 private:
  string pre;
  int next;
};


#endif