[LispM-Hackers] memFEFHeader::readMacroInstruction

[Dave Richards]

Based on "Figure 11-3  The Layout of a FEF" in SSDN2:

      1
     +-+-+---------+-+-----+-----+-------+-------+-------------------+
    0|Q|S|DTP-FEF-H|M| CT  |#opt | #req  | #loc  | PC word offset    |
     +-+-+---------+-+-----+-----+-------+-------+-------------------+
    1|cc |DTP-FIX  |      length of function                         |
     +---+---------+-------------------------------------------------+
    2|cc |DTP-LIST |  pointer to debugging info                      |
     +---+---------+-----+-+-+-+-----------+-----------+-------------+
    3|cc |DTP-FIX  |     |O|L|R|min # args |max # args | # locals    |
     +---+---------+-----+-+-+-+-----------+-----------+-------------+
     |cc |DTP-SYMBO|  pointer to name of flavor for a method         |
     +---+---------+-------------------------------------------------+
     |cc |         |     first constant                              |
     +---+---------+-------------------------------------------------+



     +---+---------+-------------------------------------------------+
     |   |         |     last constant                               |
     +---+---------+------------------+------------------------------+
     |     second instruction         |  first instruction           |
     +--------------------------------+------------------------------+
     |     fourth instruction         |  third instruction           |
     +--------------------------------+------------------------------+

I believe:

e3MacroInstruction memFEFHeader::readMacroInstruction(e3u32 entry_offset,
e3u
8 relative_pc) const
{
  e3Word foo = readWordAt(myWordAddress + entry_offset + (relative_pc / 2));

  if (!(relative_pc & 0x1))             // Even or high word.
    {
      e3MacroInstruction retval((foo.getBits() >> 16) & 0xffff);
      return(retval);
    }
  else                          // Odd or low word.
    {
      e3MacroInstruction retval(foo.getBits() & 0xffff);
      return(retval);
    }
}

is backwards.

  if (!(relative_pc & 0x1))             // Even or high word.

should be:

  if (relative_pc & 0x1)                // Even or high word.

On a different topic.  In reading the code, I see references in word.h to
section 7.  I didn't see it up there.  Is sect07.txt available?

	Dave