jvmhelp.java

Java Op Processor java vhdl processor

package com.jopdesign.sys;

//
//	I don't like to make JVMHelp public, but I need it in java.io.PrintStream
//
// class JVMHelp {
public class JVMHelp {

	//
	// DON'T change order of first functions!!!
	//	interrupt gets called from jvm.asm
	//
	public static void interrupt() {
// RtThread.ts0 = Native.rd(Const.IO_US_CNT);
		RtThreadImpl.schedule();
// Scheduler.schedInt();
	}


	public static void nullPoint() {

Object o = new Object();
synchronized (o) {
		int i;
		wr('n');
		wr('p');
		wr(' ');

		int sp = Native.getSP();			// sp of ();
		int pc = Native.rdIntMem(sp-3);		// pc is not exact (depends on instruction)
		i = Native.rdIntMem(sp);			// mp
wrSmall(i);
wr(' ');
		int start = Native.rdMem(i)>>>10;	// address of method
wrSmall(start);
wr(' ');
wrByte(pc);

		trace();

		for (;;);
}
	}

	public static void arrayBound() {

Object o = new Object();
synchronized (o) {
		int i;
		wr('a');
		wr('b');
		wr(' ');

		int sp = Native.getSP();			// sp of ();
		int pc = Native.rdIntMem(sp-3);		// pc is not exact (depends on instruction)
		i = Native.rdIntMem(sp);			// mp
wrSmall(i);
wr(' ');
		int start = Native.rdMem(i)>>>10;	// address of method
wrSmall(start);
wr(' ');
wrByte(pc);

		trace();

		for (;;);
}
	}
	
	/**
	 * Invoked on a hardware generated exception.
	 * Currently only on stack overflow and integer
	 * division, remainder by zero.
	 */
	static void except() {
		
		int i;
		i = Native.rdMem(Const.IO_EXCPT);
		JVMHelp.wr("\nException: ");
		if (i==1) {
			JVMHelp.wr("Stack overflow\n");
		} else if (i==2) {
			JVMHelp.wr("ArithmeticException\n");
		}

		int sp = Native.getSP();			// sp of ();
		int pc = Native.rdIntMem(sp-3);		// pc is not exact (depends on instruction)
		i = Native.rdIntMem(sp);			// mp
wrSmall(i);
wr(' ');
		int start = Native.rdMem(i)>>>10;	// address of method
wrSmall(start);
wr(' ');
wrByte(pc);

		trace();

		for (;;);
	}

	static void noim() {

		int i;
		wr('n');
		wr('i');
		wr(' ');
		i = Native.getSP();					// sp of noim();
		int sp = Native.rdIntMem(i-4);		// sp of calling function
		int pc = Native.rdIntMem(sp-3)-1;	// one to high
		i = Native.rdIntMem(sp);			// mp
wrSmall(i);
wr(' ');
		int start = Native.rdMem(i)>>>10;
wrSmall(start);
wr(' ');
wrByte(pc);
wr(' ');

		int val = Native.rdMem(start+(pc>>2));
		for (i=(pc&0x03); i<3; ++i) val >>= 8;
		val &= 0xff;
		wrByte(val);

Object o = new Object();
synchronized (o) {

		System.out.println();
		System.out.print("JOP: bytecode ");
		System.out.print(val);
		System.out.println(" not implemented");

		trace();

		for (;;);
}
	}


	static void trace() {

		int fp, mp, vp, pc, addr, loc, args;
		int val;

		int sp = Native.getSP();			// sp after call of trace();
		fp = sp-4;		// first frame point is easy, since last sp points to the end of the frame

		wr('\n');

//		while does not work anymore as sp and vp are
//		wrapping around (only 7 bits)
//		while (fp>128+5) {	// stop befor 'fist' method
		for (int cnt=0; cnt<3; ++cnt) {
			mp = Native.rdIntMem(fp+4);
			vp = Native.rdIntMem(fp+2);
			pc = Native.rdIntMem(fp+1);
			val = Native.rdMem(mp);
			addr = val>>>10;			// address of callee

			wrSmall(mp);
			wrSmall(addr);
			wrSmall(pc);
			wr('\n');

			val = Native.rdMem(mp+1);	// cp, locals, args
			args = val & 0x1f;
			loc = (val>>>5) & 0x1f;
			fp = vp+args+loc;			// new fp can be calc. with vp and count of local vars
		}
		wr('\n');
for (fp=128; fp<=sp; ++fp) {
	wrSmall(Native.rdIntMem(fp));
}
		wr('\n');
/*
for (fp=10530; fp<=10700; ++fp) {
	wrSmall(Native.rdMem(fp));
}
*/
	}


	static void wrByte(int i) {

		wr('0'+i/100);
		wr('0'+i/10%10);
		wr('0'+i%10);
		wr(' ');
	}

	static void wrSmall(int i) {

		wr('0'+i/100000%10);
		wr('0'+i/10000%10);
		wr('0'+i/1000%10);
		wr('0'+i/100%10);
		wr('0'+i/10%10);
		wr('0'+i%10);
		wr(' ');
	}


	public static void wr(int c) {
		
		// busy wait on free tx buffer
		// but ncts is not used anymore =>
		// no wait on an open serial line, just wait
		// on the baud rate
		while ((Native.rd(Const.IO_STATUS)&1)==0) {
			;
		}
		Native.wr(c, Const.IO_UART);
		// this is the USB port
		/* we will NOT wait for the USB device to be compatible
		   with other configurations. The UART limits the transfer rate
		   to about 10kB/s.
		   
		while ((Native.rdMem(Const.IO_USB_STATUS) & Const.MSK_UA_TDRE)==0) {
			;
		}
		*/
		// disable for OEBB project
		Native.wrMem(c, Const.IO_USB_DATA);
	}
	
	static void wr(String s) {

		int i = s.length();
		for (int j=0; j<i; ++j) {
			wr(s.charAt(j));
		}
	}

	private static final int MAX_TMP = 32;
	private static int[] tmp;			// a generic buffer

	static void intVal(int val) {

		if (tmp==null) tmp = new int[MAX_TMP];
		int i;
		if (val<0) {
			wr('-');
			val = -val;
		}
		for (i=0; i<MAX_TMP-1; ++i) {
			tmp[i] = (val%10)+'0';
			val /= 10;
			if (val==0) break;
		}
		for (val=i; val>=0; --val) {
			wr(tmp[val]);
		}
		wr(' ');
	}

}