18 Jun
2026
18 Jun
'26
1:28 p.m.
On Jun 18, 2026, at 3:12 PM, Fred Cisin via cctalk
<cctalk(a)classiccmp.org> wrote:
That depends. For CDC 6600 programmers it was a routine part of every day. For PDP-11
programmers, probably not so much.
You can see the difference that skill makes in the 6600 case when you read the OS sources,
and observe how code is arranged to optimize the use of the multiple functional units and
the instruction packing. Some others did this less diligently, and it made a difference
as I found out at PLATO.
paul
> The IBM 1401 COBOL compiler wrote assembler
(Autocoder) on a tape. Then
> you had to mount the Autocoder assembler tape and assemble it. And it
> included the input COBOL code as Autocoder comments.
On Thu, 18 Jun 2026, Bill Gunshannon via cctalk wrote:
Interesting. I did Autocoder but never thought
of it as assembler.
Programming the 1401 in assembler was when you took the output from
an Autocder deck and hand optimized it to a single card. :-)
Hand otimizing was more likely machine language programming rather than "programming
in assembler".