[Bruce Abbott]

Originally Posted by meynaf

Not if it is located in the middle of a longword. Actually, out of 4 possible alignment cases, only one will require two accesses.

Still less efficient than being word-aligned. And a longword will be misaligned in 3 out of 4 cases.

And as the exact same code has to handle both cases (it can't know if the data is currently aligned or not), it is a lot faster than having to realign before making the memory access.

Sounds like a fairly specific application. Why can't the alignment be set in advance?

Sure i don't micromanage all single bytes. But would you really accept to waste kilobytes to padding ?

I don't care about a few kilobytes. Modern programs 'waste' hundreds of kilobytes without even thinking about it. But if I had some data that wasted a lot of space for alignment (or any other reason) I would consider a more efficient format.

I use 68020 things all the time. 68000 is a PITA (in comparison).

There are specific cases where 020 code is a bit more efficient and saves some typing, but the vast majority of '68020 optimized' programs I have analyzed had very few 68020 instructions in them. I haven't felt the need to use it my own code. I might if I was coding something specifically for the A1200 and wanted the fastest speed possible - but then I have a 50MHz 030 so speed isn't usually an issue for me (a bigger problem is considering other users with slower machines).

It's not worse than all these programs using the fpu and crashing 8000000F without a warning. Or these who work on 68000 and fail on anything else.

I am looking at them. Take AmigaBASIC for example. Whoever coded it should have been shot.

I don't care about traditions.

So why are you programming in machine code on a platform that hasn't changed in 30 years?