Re: Any more graceful way to saturate adds?

Jim Leonard wrote:
> On Apr 22, 1:01 pm, Terje Mathisen  <spamt...@[EMAIL PROTECTED]
> wrote:
>> The gain is that we save one opcode byte (MOV instead of JMP SHORT) and
>> a taken branch, so the actual cost of rotating the loop like this is 8
>> cycles on the first iteration, instead of 17, and each iteration saves
>> two opcode bytes or 8 cycles.
> 
> I hate to seem more daft than I already am, but after re-reading the
> above for a week I still don't get the trick.  I thought ORG was for
> specifying where the assembler assumes the binary code will get
> loaded; how does that save two opcode bytes per iteration?

Pete wrote a good explanation, using ORG together with $ is for relative 
instead of absolute addresses.

The two bytes saved per iteration was the unconditional jump from the 
bottom of the loop, getting rid of those required the loop to be 
rotated, i.e. moving the STOSB to the top, and getting rid of the 
initial jump past this opcode was the reason for my dummy immediate 
instruction.

Terje

-- 
- <Terje.Mathisen@[EMAIL PROTECTED]
>
"almost all programming can be viewed as an exercise in caching"