Package mars

Class MIPSprogram

java.lang.Object
mars.MIPSprogram
public class MIPSprogram extends Object
Internal representations of MIPS program. Connects source, tokens and machine code. Having all these structures available facilitates construction of good messages, debugging, and easy simulation.
Version:
August 2003
Author:
Pete Sanderson

  • Constructor Details

    • MIPSprogram

      public MIPSprogram()

  • Method Details

    • getSourceList

      public ArrayList<String> getSourceList()
      Produces list of source statements that comprise the program.
      Returns:
      ArrayList of String. Each String is one line of MIPS source code.

    • setSourceLineList

      public void setSourceLineList​(ArrayList<SourceLine> sourceLineList)
      Set list of source statements that comprise the program.
      Parameters:
      sourceLineList - ArrayList of SourceLine. Each SourceLine represents one line of MIPS source code.

    • getSourceLineList

      public ArrayList<SourceLine> getSourceLineList()
      Retrieve list of source statements that comprise the program.
      Returns:
      ArrayList of SourceLine. Each SourceLine represents one line of MIPS source cod

    • getFilename

      public String getFilename()
      Produces name of associated source code file.
      Returns:
      File name as String.

    • getTokenList

      public ArrayList<TokenList> getTokenList()
      Produces list of tokens that comprise the program.
      Returns:
      ArrayList of TokenList. Each TokenList is list of tokens generated by corresponding line of MIPS source code.
      See Also:
      TokenList

    • getTokenizer

      public Tokenizer getTokenizer()
      Retrieves Tokenizer for this program
      Returns:
      Tokenizer

    • createParsedList

      public ArrayList<ProgramStatement> createParsedList()
      Produces new empty list to hold parsed source code statements.
      Returns:
      ArrayList of ProgramStatement. Each ProgramStatement represents a parsed MIPS statement.
      See Also:
      ProgramStatement

    • getParsedList

      public ArrayList<ProgramStatement> getParsedList()
      Produces existing list of parsed source code statements.
      Returns:
      ArrayList of ProgramStatement. Each ProgramStatement represents a parsed MIPS statement.
      See Also:
      ProgramStatement

    • getMachineList

      public ArrayList<ProgramStatement> getMachineList()
      Produces list of machine statements that are assembled from the program.
      Returns:
      ArrayList of ProgramStatement. Each ProgramStatement represents an assembled basic MIPS instruction.
      See Also:
      ProgramStatement

    • getBackStepper

      public BackStepper getBackStepper()
      Returns BackStepper associated with this program. It is created upon successful assembly.
      Returns:
      BackStepper object, null if there is none.

    • getLocalSymbolTable

      public SymbolTable getLocalSymbolTable()
      Returns SymbolTable associated with this program. It is created at assembly time, and stores local labels (those not declared using .globl directive).

    • backSteppingEnabled

      public boolean backSteppingEnabled()
      Returns status of BackStepper associated with this program.
      Returns:
      true if enabled, false if disabled or non-existant.

    • getSourceLine

      public String getSourceLine​(int i)
      Produces specified line of MIPS source program.
      Parameters:
      i - Line number of MIPS source program to get. Line 1 is first line.
      Returns:
      Returns specified line of MIPS source. If outside the line range, it returns null. Line 1 is first line.

    • readSource

      public void readSource​(String file) throws ProcessingException
      Reads MIPS source code from file into structure. Will always read from file. It is GUI responsibility to assure that source edits are written to file when user selects compile or run/step options.
      Parameters:
      file - String containing name of MIPS source code file.
      Throws:
      ProcessingException - Will throw exception if there is any problem reading the file.

    • tokenize

      public void tokenize() throws ProcessingException
      Tokenizes the MIPS source program. Program must have already been read from file.
      Throws:
      ProcessingException - Will throw exception if errors occurred while tokenizing.

    • prepareFilesForAssembly

      public ArrayList<MIPSprogram> prepareFilesForAssembly​(ArrayList<String> filenames, String leadFilename, String exceptionHandler) throws ProcessingException
      Prepares the given list of files for assembly. This involves reading and tokenizing all the source files. There may be only one.
      Parameters:
      filenames - ArrayList containing the source file name(s) in no particular order
      leadFilename - String containing name of source file that needs to go first and will be represented by "this" MIPSprogram object.
      exceptionHandler - String containing name of source file containing exception handler. This will be assembled first, even ahead of leadFilename, to allow it to include "startup" instructions loaded beginning at 0x00400000. Specify null or empty String to indicate there is no such designated exception handler.
      Returns:
      ArrayList containing one MIPSprogram object for each file to assemble. objects for any additional files (send ArrayList to assembler)
      Throws:
      ProcessingException - Will throw exception if errors occurred while reading or tokenizing.

    • assemble

      public ErrorList assemble​(ArrayList<MIPSprogram> MIPSprogramsToAssemble, boolean extendedAssemblerEnabled) throws ProcessingException
      Assembles the MIPS source program. All files comprising the program must have already been tokenized. Assembler warnings are not considered errors.
      Parameters:
      MIPSprogramsToAssemble - ArrayList of MIPSprogram objects, each representing a tokenized source file.
      extendedAssemblerEnabled - A boolean value - true means extended (pseudo) instructions are permitted in source code and false means they are to be flagged as errors.
      Returns:
      ErrorList containing nothing or only warnings (otherwise would have thrown exception).
      Throws:
      ProcessingException - Will throw exception if errors occurred while assembling.

    • assemble

      public ErrorList assemble​(ArrayList<MIPSprogram> MIPSprogramsToAssemble, boolean extendedAssemblerEnabled, boolean warningsAreErrors) throws ProcessingException
      Assembles the MIPS source program. All files comprising the program must have already been tokenized.
      Parameters:
      MIPSprogramsToAssemble - ArrayList of MIPSprogram objects, each representing a tokenized source file.
      extendedAssemblerEnabled - A boolean value - true means extended (pseudo) instructions are permitted in source code and false means they are to be flagged as errors
      warningsAreErrors - A boolean value - true means assembler warnings will be considered errors and terminate the assemble; false means the assembler will produce warning message but otherwise ignore warnings.
      Returns:
      ErrorList containing nothing or only warnings (otherwise would have thrown exception).
      Throws:
      ProcessingException - Will throw exception if errors occurred while assembling.

    • simulate

      public boolean simulate​(int[] breakPoints) throws ProcessingException
      Simulates execution of the MIPS program. Program must have already been assembled. Begins simulation at beginning of text segment and continues to completion.
      Parameters:
      breakPoints - int array of breakpoints (PC addresses). Can be null.
      Returns:
      true if execution completed and false otherwise
      Throws:
      ProcessingException - Will throw exception if errors occurred while simulating.

    • simulate

      public boolean simulate​(int maxSteps) throws ProcessingException
      Simulates execution of the MIPS program. Program must have already been assembled. Begins simulation at beginning of text segment and continues to completion or until the specified maximum number of steps are simulated.
      Parameters:
      maxSteps - maximum number of steps to simulate.
      Returns:
      true if execution completed and false otherwise
      Throws:
      ProcessingException - Will throw exception if errors occurred while simulating.

    • simulateFromPC

      public boolean simulateFromPC​(int[] breakPoints, int maxSteps, AbstractAction a) throws ProcessingException
      Simulates execution of the MIPS program. Program must have already been assembled. Begins simulation at current program counter address and continues until stopped, paused, maximum steps exceeded, or exception occurs.
      Parameters:
      breakPoints - int array of breakpoints (PC addresses). Can be null.
      maxSteps - maximum number of instruction executions. Default -1 means no maximum.
      a - the GUI component responsible for this call (GO normally). set to null if none.
      Returns:
      true if execution completed and false otherwise
      Throws:
      ProcessingException - Will throw exception if errors occurred while simulating.

    • simulateStepAtPC

      public boolean simulateStepAtPC​(AbstractAction a) throws ProcessingException
      Simulates execution of the MIPS program. Program must have already been assembled. Begins simulation at current program counter address and executes one step.
      Parameters:
      a - the GUI component responsible for this call (STEP normally). Set to null if none.
      Returns:
      true if execution completed and false otherwise
      Throws:
      ProcessingException - Will throw exception if errors occurred while simulating.

    • inSteppedExecution

      public boolean inSteppedExecution()
      Will be true only while in process of simulating a program statement in step mode (e.g. returning to GUI after each step). This is used to prevent spurious AccessNotices from being sent from Memory and Register to observers at other times (e.g. while updating the data and register displays, while assembling program's data segment, etc).

    • createMacroPool

      public MacroPool createMacroPool()
      Instantiates a new MacroPool and sends reference of this MIPSprogram to it
      Returns:
      instantiated MacroPool

    • getLocalMacroPool

      public MacroPool getLocalMacroPool()
      Gets local macro pool MacroPool for this program
      Returns:
      MacroPool

    • setLocalMacroPool

      public void setLocalMacroPool​(MacroPool macroPool)
      Sets local macro pool MacroPool for this program
      Parameters:
      macroPool - reference to MacroPool