function _memset(ptr, value, num) {
 ptr = ptr | 0;
 value = value | 0;
 num = num | 0;
 var stop = 0, value4 = 0, unaligned = 0;
 stop = ptr + num | 0;
 if ((num | 0) >= 20) {
  value = value & 255;
  unaligned = ptr & 3;
  value4 = value | value << 8 | value << 16 | value << 24;
  if (unaligned) {
   unaligned = ptr + 4 - unaligned | 0;
   while ((ptr | 0) < (unaligned | 0)) {
    HEAP8[ptr] = value;
    ptr = ptr + 1 | 0;
   }
  }
  while ((ptr | 0) < (stop & ~3 | 0)) {
   HEAP32[ptr >> 2] = value4;
   ptr = ptr + 4 | 0;
  }
 }
 while ((ptr | 0) < (stop | 0)) {
  HEAP8[ptr] = value;
  ptr = ptr + 1 | 0;
 }
}