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Vapor Parser and AST

This parser and AST handles both Vapor and Vapor-M programs. Compile your program against the provided JAR file using the "-classpath" option.

• JAR: vapor-parser.jar
• Javadoc: View Online | Tarball
• Source: View Online | Tarball

To parse a Vapor program:

import cs132.util.ProblemException;
import cs132.vapor.parser.VaporParser;
import cs132.vapor.ast.VaporProgram;
import cs132.vapor.ast.VBuiltIn.Op;

import java.io.InputStreamReader;
import java.io.IOException;
import java.io.PrintStream;

...

public static VaporProgram parseVapor(InputStream in, PrintStream err)
  throws IOException
{
  Op[] ops = {
    Op.Add, Op.Sub, Op.MulS, Op.Eq, Op.Lt, Op.LtS,
    Op.PrintIntS, Op.HeapAllocZ, Op.Error,
  };
  boolean allowLocals = true;
  String[] registers = null;
  boolean allowStack = false;

  VaporProgram program;
  try {
    program = VaporParser.run(new InputStreamReader(in), 1, 1,
                              java.util.Arrays.asList(ops),
                              allowLocals, registers, allowStack);
  }
  catch (ProblemException ex) {
    err.println(ex.getMessage());
    return null;
  }

  return program;
}

To parse a Vapor-M program, it's the same thing except:

  boolean allowLocals = false;
  String[] registers = {
    "v0", "v1",
    "a0", "a1", "a2", "a3",
    "t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7",
    "s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
    "t8",
  };
  boolean allowStack = true;

A Vapor program will never contain the following AST nodes: VVarRef.Register, VMemRef.Stack. A Vapor-M program will never contain the following AST node: VVarRef.Local.