Quick, dirty and non-efficient wdc 65816 compiler

qdnec

<?php
/**qdnec help
Function declaration:
%f <name>; <Function body> %F;
Expression:
0=<main expression>;
Association:
<address (without $ or 0x)>=<main expression>;
Arithmetic Operations:
+ Addition
- Subtraction
* Multiplication
/ Divide
( ) Parthensis
note: operations like 5(a()-$2) are NOT possible
use 5*(a()-$2) instead.
Variables: does not really exists,use addresses instead
Adresses:
Lorom/Hirom addresses with $ as prefix.
function calls:
<name>()
If:
%i<addr1>==<addr2>:<expressions if true>(%e<expressions if false>)%I;
(Expressions, Associations and conditional blocks are expressions)
*/
$look="";
$lcount=0;
$inFunction=false;
$done=false;
function getChar() {
	global $look;
	$look=fgetc(STDIN);
}
function abort($str) {
	die("\nError: $str.");
}
function expected($str) {
	abort("$str expected");
}
function newLabel() {
	global $lcount;
	$lcount++;
	return "L".($lcount-1);
}
function postLabel($l){
	echo "$l:\n";
}
function isAlpha($c) {
	$array=array("a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z");
	$c=strtolower($c);
	for($i=0;$i<count($array);$i++) {
		if ($array[$i]==$c)
			return true;
	}
	return false;
}
function isAlNum($c) {
	return isAlpha($c) || is_numeric($c);
}
function isWhite($c) {
	return $c==" ";
}
function isHexa($c) {
	$array=array("0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f");
	$c=strtolower($c);
	for($i=0;$i<count($array);$i++) {
		if ($array[$i]==$c)
			return true;
	}
	return false;
}
function skipWhite() {
	global $look;
	while(isWhite($look))
		getChar();
}
function match($c) {
	global $look;
	if($look==$c) {
		getChar();
		skipWhite();
	}
	else
		expected($c);
}
function getAddress() {
	global $look;
	if(!isHexa($look)) {
		expected("address");
	}
	$tmp="$";
	while(isHexa($look)) {
		$tmp.=$look;
		getChar();
	}
	skipWhite();
	return $tmp;
}
function getName() {
	global $look;
	if(!isAlpha($look)) 
		expected("name");
	$tmp="";
	while(isAlNum($look)) {
		$tmp.=$look;
		getChar();
	}
	skipWhite();
	return $tmp;
}
function getNum() {
	global $look;
	$tmp="";
	if(!is_numeric($look)) 
		expected("integer");
	while(is_numeric($look)) {
		$tmp.=$look;
		getChar();
	}
	skipWhite();
	return $tmp;
}
function ident() {
	global $look;
	$name=getName();
	if($look=="(") {
		match("(");
		match(")");
		echo "JSR $name\n";
	} else
		echo "LDA $name\n";
}
function factor() {
	global $look;
	if($look=="(") {
		match("(");
		expression();
		match(")");
	} else if (isAlpha($look))
		ident();
	else if ($look=="$") {
		//Address
		match("$");
		echo "LDA ".getAddress()."\n";
	} else
		echo "LDA #".getNum()."\n";
}
function multiply() {
	match("*");
	factor();
	echo "PLX\nSTA $2102\nSTX $2103\nNOP\nNOP\nNOP\nNOP\nNOP\nNOP\nNOP\nNOP\nLDA $4217 ;low 8 bit.\n";
}
function divide() {
	match("/");
	factor();
	echo "STZ $4204\nPLX\nSTX $4205\nSTA $4206\nNOP\nNOP\nNOP\nNOP\nNOP\nNOP\nNOP\nNOP\nLDA $4214\n";
}
function term() {
	global $look;
	factor();
	while(($look=="*")||($look=="/")) {
		echo("PHA\n");
		switch($look) {
			case "*":
				multiply();
				break;
			case "/":
				divide();
				break;
			default:
				expected("mulop");
		}
	}
}
function add() {
	global $look;
	match("+");
	term();
	echo "PLX\nSTX $0000\nCLC\nADC $0000\n";
}
function subtract() {
	match("-");
	global $look;
	term();
	echo "PLX\nSTX $0000\nSEC\nSBC $0000\nEOR #\$"."FF\nINA\n";
}
function expression() {
	global $look;
	$addr=getAddress();
	match("=");
	if(($look=="+")||($look=="-"))
		echo "LDA #0\n";
	else
		term();
	while(($look=="+")||($look=="-")) {
		echo("PHA\n");
		switch($look) {
			case "+":
				add();
				break;
			case "-":
				subtract();
				break;
			default:
				expected("addop");
		}
	}
	match(";");
	echo "STA $addr\n";
}
function condition() {
	$addr1=getAddress();
	match("=");
	match("=");
	$addr2=getAddress();
	echo "LDA $addr1\nSEC\nSBC $addr2\n";
	match(":");
	return array($addr1,$addr2);
}
function cmain() {
	global $look;
	global $inFunction;
	global $done;
	match("%");
	if ($look=="i" && $inFunction) {
		match("i");
		$l = newLabel();
		$addr=condition();
		$addr1=$addr[0];
		$addr2=$addr[1];
		echo "BNE $l\n";
		while(isHexa($look)) {
			expression();
		}
		match("%");
		if($look=="i") {
			cmain();
			match("%");
		}
		postLabel($l);
		if($look=="e") {
			match("e");
			echo "LDA $addr1\nSEC\nSBC $addr2\n";
			$l = newLabel();
			echo "BEQ $l\n";
			while(isHexa($look)) {
				expression();
			}
			match("%");
			if($look=="i") {
				cmain();
				match("%");
			}
			postLabel($l);
		}
		match("I");
		match(";");
	} else if($look=="f") {
		match("f");
		echo getName().":\n";
		match(";");
		$inFunction=true;
	} else if($look=="F") {
		match("F");
		match(";");
		echo "RTS\n";
		$inFunction=false;
	} else {
		$done=true;
	}
}
function init() {
	global $look;
	global $inFunction;
	global $done;
	getChar();
	while(!$done) {
		if($look=="%") 
			cmain();
		else if($inFunction )
			while(isHexa($look))
				expression();
	}
}
init();