On 03/07/2010 07:23 AM, Brian Haag wrote:
    It is better to see indexed addressing in terms of accessing arrays.
    Say you have an array of 20 integers in memory.
    (One integer = 4 bytes)
    Now you can acces these in a loop, by using an index and the fixed
    multiplier of 4 (4 bytes is the size of one element of the array).

    so 1st element: index = 0 in %edi, address with "start_array (,%edi,4)"
    next element: increment %edi and use same statement
    ("start_array(,%edi,4)")
    etc.

    When you have an array of characters (1 byte) then your multiplier is 1.


This makes perfect sense to me, and is what I expected in the first
place.  Now that I read it again, the book does seem consistent with
it---it's just described in a way I couldn't follow.  Specifically, what
I wasn't putting together well is that the multiplier specifies the
length of an element (whether a record an array element), and the index
register specifies "how many elements" from the address.

Anyway, got it now.  Thanks to both of you.

Yeah, I had it backwards. <hangs head in shame>. /herbc



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