//  $Id: JIT.java,v 1.11 1999/03/09 01:57:30 pab Exp $//  JIT.java - main entry point for java execution engine using just-in-time//      compilation for methods.package toba.jit;import toba.classfile.*;import toba.runtime.*;import java.util.*;class JIT {    static void usage() {	System.out.println("usage: JIT classname [args]");	Runtime.getRuntime().exit(1);    }    /** Native function to invoke a void(String[]) function at a given address.      * @param addr the address of the function entry point      * @param args the arguments to the function.      * Toba hash: laS_r1YxG      */    static native void    startMain (long addr,               String args[]);    // Driver procedures for the command-line version of the JIT    static public void main(String args[]) 	throws ClassNotFoundException    {	String classname = null; // the name of the class to interpret	Properties sysprops = null;	int nargs = 0;	for (int i = 0; (i < args.length) && (classname == null); i++) {	    String arg = args[i];	    nargs++;	    if (arg.charAt(0) != '-')		classname = arg;	    else if (arg.charAt(1) == 'D') {		int sepindex = arg.indexOf('=');		if (sepindex < 0)		    usage();		String propname = arg.substring(2, sepindex);		String propval  = arg.substring(sepindex+1);		if (sysprops == null)		    sysprops = System.getProperties();		sysprops.put(propname, propval);	    } else {		usage();	    }	}	// I should have a class name to run by now	if (null == classname) {	    usage();        }        JITCodeGen.Initialize ();        JITCodeGen jcg = (JITCodeGen) CodeGen.getGenerator ();        if (null != System.getProperty ("jtoba_instrument")) {            jcg.InitInstrumentation ();        }	Class cl = toba.runtime.SystemClassLoader.systemLoadClass(classname, true);		/* Create a descriptor for the main method */	ClassRef cref = ClassRef.byName (classname);	MethodRef mref = new MethodRef(cref, "main", "([Ljava/lang/String;)V");	/* Resolve the class and method ref */	cref.resolveTo(cl, null);	mref.resolveWith(ClassRT.getClassData(cl));        Method mt = (Method) mref.getField ().tableObj;        if ((null != mt) && (null != mt.mtcode)) {            /* This is a JIT-loaded class (as opposed to a pre-compiled             * class that we happen to be starting through the jit).             * Make sure that the entry point is resolved. */            if (! mt.mtcode.getIsResolved ()) {                mt.mtcode.resolveCode ();            }        }        // Copy arguments into a string array	String[] argstrings = new String[args.length - nargs];	for (int i = nargs; i < args.length; i++) {	    argstrings[i - nargs] = args[i];        }        long addr = ClassRT.getMethodAddr (cl, mref.getField());        startMain (addr, argstrings);        jcg.SummarizeInstrumentation ();    }}