Code: Select all
<?php
class SHVM {
public $MAX_CYCLES = 10000;
private $movin = array(array(1, 0), array(0, -1), array(-1, 0), array(0, 1));
// public $MEM_HEIGHT = 8;
public $MEM_HEIGHT = 128;
public $MEM_WIDTH = 1024;
public $MAX_THREADS = 32;
private $timeToQuit = false;
public $Memory = array();
public $Threads = array();
public $Code = array();
public $user_input = array();
public $trace = false;
private $t = NULL;
public $cycle_count = 0;
private function InitStuff() {
$this->timeToQuit = false;
$this->Code = array();
$this->Memory = array();
for ($i = 0; $i < $this->MEM_HEIGHT; $i++) {
$this->Memory[$i] = array_fill(0, $this->MEM_WIDTH, 0);
}
$this->Threads = array();
$this->t = array();
$this->t['pcX'] = 0; $this->t['pcY'] = 0;
$this->t['mX'] = -1; $this->t['mY'] = 0;
$this->t['dir'] = 0;
$this->t['cs'] = array();
$this->Threads[0] = $this->t;
}
private function Push($v) {
if ($v > 2147483647 || $v < -2147483648) throw new Exception("integer overflow: '$v'");
$this->t['mX'] += 1;
$this->Memory[$this->t['mY']][$this->t['mX']] = $v;
}
private function Pop() {
if ($this->t['mX'] < 0) throw new Exception("stack underflow");
$v = $this->Memory[$this->t['mY']][$this->t['mX']];
$this->t['mX'] -= 1;
return $v;
}
private function MoveOneStep() {
$this->t['pcX'] += $this->movin[$this->t['dir']][0];
$this->t['pcY'] += $this->movin[$this->t['dir']][1];
}
function Run($code, $mem_init, $traceIt = false) {
$this->InitStuff();
$output = "";
$message = "";
$result = 0;
$lines = preg_split('/[\n\r]+/', $code);
// print_r($lines);
for ($y = 0; $y < count($lines); $y++) {
$this->Code[$y] = array();
for ($x = 0; $x < strlen($lines[$y]); $x++) {
$c = $lines[$y][$x];
$this->Code[$y][$x] = $c;
if ($c == '%') {
$this->Threads[0]['pcX'] = $x;
$this->Threads[0]['pcY'] = $y;
}
}
}
// initialize the memory
$mem_init_cells = explode(",", $mem_init);
for ($i=0; $i<count($mem_init_cells); $i++) {
$this->user_input[$i] = (int)trim($mem_init_cells[$i]);
}
$this->user_input = array_reverse($this->user_input);
// run loop
try {
while (!$this->timeToQuit) {
// check that we don't exceed the max
if ($this->cycle_count++ > $this->MAX_CYCLES) throw new Exception('too many cycles: ' . $this->cycle_count);
for ($tindex = 0; $tindex < count($this->Threads); $tindex++) {
$this->t =& $this->Threads[$tindex];
// some convenience vars
$t =& $this->t;
$pcX =& $t['pcX']; $pcY =& $t['pcY'];
$mX =& $t['mX']; $mY =& $t['mY'];
$mem =& $this->Memory;
$dir =& $t['dir'];
// print_r($this->t);
if ($pcY < 0 || $pcX < 0) throw new Exception('out of code bounds');
if (!isset($this->Code[$pcY])) {
$s = 'undefined code vert: ' . $mX.",xxxxxx". $pcX;
throw new Exception($s);
}
if (!isset($this->Code[$pcY][$pcX])) throw new Exception('undefined code: ' . $pcY.",". $pcX);
$instruction = $this->Code[$t['pcY']][$pcX];
$ox = $pcX; $oy = $pcY;
if ($traceIt) echo "[Thread $tindex] <b>$instruction</b> @$ox,$oy [".implode(',', array_slice($this->Memory[$mY], 0, $mX + 1) )."]\n<br>";
// if ($traceIt) echo "[Thread $tindex] <b>$instruction</b> @$ox,$oy [".implode(',', array_splice(0, $this->Memory[$this->t['mY']], $mX + 1))."]\n<br>";
// instruction dispatch
switch ($instruction) {
case ' ': break;
case '0': $this->Push(0); break;
case '1': $this->Push(1); break;
case '2': $this->Push(2); break;
case '3': $this->Push(3); break;
case '4': $this->Push(4); break;
case '5': $this->Push(5); break;
case '6': $this->Push(6); break;
case '7': $this->Push(7); break;
case '8': $this->Push(8); break;
case '9': $this->Push(9); break;
case '+': $this->Push($this->Pop()+$this->Pop()); break;
case '-': $a = $this->Pop(); $b = $this->Pop(); $this->Push($b-$a); break;
case '*': $this->Push($this->Pop()*$this->Pop()); break;
case 'd': $a = $this->Pop(); $b = $this->Pop(); $this->Push(floor($b/$a)); break;
case '\\': $dir = ($dir ^ 3); break;
case '/': $dir = ($dir ^ 1); break;
case 'p': $output .= $this->Pop(); break;
case 'P': $output .= chr($this->Pop()&0x7F); break;
case ':': $a = $this->Pop(); $b = $this->Pop(); if ($b<$a) $dir = ($dir + 1) % 4; else if ($b > $a) $dir = ($dir + 3) % 4; break;
// case ':': $a = $this->Pop(); $b = $this->Pop(); $this->Push( ($b<$a)?-1:(($b==$a)?0:1)); break;
case ',': if (count($this->user_input) > 0) $this->Push(array_pop($this->user_input)); else $this->Push(0); break;
case 's': $this->MoveOneStep(); break;
case '?': $a = $this->Pop(); if ($a == 0) $this->MoveOneStep(); break;
case '@':
array_push($this->t['cs'], array($pcX, $pcY, $dir));
break;
case '$':
if (count($this->t['cs']) == 0) throw new Exception("call stack underflow");
$c = array_pop($this->t['cs']);
$pcX = $c[0]; $pcY = $c[1]; $dir = $c[2];
$this->MoveOneStep();
break;
case '<':
$x = $this->Pop(); $y = $this->Pop();
if ($x < 0 || $y < 0) throw new Exception('memory read access violation @'.$x.",".$y);
if ($y >= count($this->Memory))
$this->Push(0);
else {
$this->Push($this->Memory[$y][$x]);
}
break;
case '>':
$x = $this->Pop(); $y = $this->Pop();
if ($x < 0 || $y < 0) throw new Exception('memory read access violation @'.$x.",".$y);
$val = $this->Pop();
$this->Memory[$y][$x] = $val;
// print_r($mem);
break;
case '[': $i = $this->Pop(); $mX -= $i; break;
case ']': $i = $this->Pop(); $mX += $i; break;
case '{': $mY--; if ($mY < 0) throw new Exception("mem cannot go neg"); break;
case '}': $mY++; if ($mY == $this->MEM_HEIGHT) throw new Exception("mem too big"); break;
case 'x': $a = $this->Pop(); $this->Push($a); $this->Push($a); break;
case '^': $a = $this->Pop();
if ($a < 0 || $mX < $a) throw new Exception("out of mem bounds: $a, $mX");
$this->Push($this->Memory[$mY][$mX - $a]); break;
case 'v':
$a = $this->Pop();
if ($a < 0 || $mX < $a) throw new Exception("out of mem bounds: $a, $mX");
$v = array_splice($this->Memory[$mY], $mX - $a, 1);
array_splice($this->Memory[$mY], $mX, 0, $v[0]); // insert value at mem
break;
case 'g':
$x = $this->Pop(); $y = $this->Pop();
$v = ord($this->Code[$y][$x]);
$this->Push($v);
break;
case 'w':
$x = $this->Pop(); $y = $this->Pop(); $c = $this->Pop();
$this->Code[$y][$x] = chr($c & 0x7f);
break;
case '&':
if (count($this->Threads) == $this->MAX_THREADS) throw new Exception("max threads exceeded: " . $this->MAX_THREADS);
$nt = array();
$nt['pcX'] = $pcX; $nt['pcY'] = $pcY;
$nt['mX'] = $mX; $nt['mY'] = $mY;
$nt['dir'] = $dir;
$nt['cs'] = array();
$nt['pcX'] += $this->movin[$dir][0];
$nt['pcY'] += $this->movin[$dir][1];
array_push($this->Threads, $nt);
$this->MoveOneStep();
break;
case '!': $this->timeToQuit = true; break;
default: break;
}
$this->MoveOneStep();
}
}
} catch (Exception $e) {
$message = $e->getMessage() . " (PC=" . ($this->t['pcX'] . ", " . $this->t['pcY']) . ")";
$result = -1;
// print_r($this);
}
return array("result" => $result, "message" => $message, "cycles" => $this->cycle_count, "output" => $output);
}
}
?>