Knuth's scheme wasn't relative bytes, nor instructions, nor even source
code lines. It was an actual coded label with very local scope. No
hazard from inserting instructions.
Yes, exactly. That's what made it maintainable and not error-prone.
So nothing fancy, it was something like this:
On 2018-08-05, at 19:21:04, Robin Vowels wrote:
> From: "Seymour J Metz"
> Sent: Monday, August 06, 2018 5:52 AM
>
>> Technical Assembly Systemm (TASS) on the 650 had something called a program
>> point.
>> A program point was a one digit label, and the references to program points
>> were
On 2018-08-05, at 19:30:25, Robin Vowels wrote:
>
> Of course. In the context, EX can modify everything.
>
> And anyway, why would you want to EX an EX?
>
Wrong question to ask a programmer. My maxim:
• Unix was not designed to stop you from doing stupid things,
because
- Original Message -
From: "Steve Thompson"
To:
Sent: Monday, August 06, 2018 4:21 AM
Subject: Re: EX
On 08/05/2018 08:13 AM, Robin Vowels wrote:
From: "Paul Gilmartin"
<0014e0e4a59b-dmarc-requ...@listserv.uga.edu>
Sent: Friday, August 03, 2018 3:09 AM
A principal use of EX
From: "Seymour J Metz"
Sent: Monday, August 06, 2018 6:05 AM
We were all very conscious of "economy in all things programming" in those
days.
We? I've been programming since 1960, and I was never concerned with how much space the source code
took.
Right, that was unimportant. And at 200
From: "Seymour J Metz"
Sent: Monday, August 06, 2018 5:52 AM
Technical Assembly Systemm (TASS) on the 650 had something called a program
point.
A program point was a one digit label, and the references to program points
were suffixed
with B for backwards and F for forward. It is perhaps the
>When labels were limited to 8 characters
That was an improvement over the 5 characters that we had on the 650 or the 6
characters that we had on the 7090.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
From: IBM Mainframe Assembler List on
>We were all very conscious of "economy in all things programming" in those
days.
We? I've been programming since 1960, and I was never concerned with how much
space the source code took. The important things were how quickly the code ran
and how easy it was to maintain. There's economy and
Technical Assembly Systemm (TASS) on the 650 had something called a program
point. A program point was a one digit label, and the references to program
points were suffixed with B for backwards and F for forward. It is perhaps the
only thing on the 650 that I miss.
Somewhat more general was
That's better than adding the lengths up yourself, but still not as robust as
using labels, either explicit or macro generated.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
From: IBM Mainframe Assembler List on behalf
of Tony Thigpen
On 08/05/2018 08:13 AM, Robin Vowels wrote:
From: "Paul Gilmartin"
<0014e0e4a59b-dmarc-requ...@listserv.uga.edu>
Sent: Friday, August 03, 2018 3:09 AM
A principal use of EX is to be able to use a register mask to
modify the
target. CDC 3800 had a clever alternative to this, a
From: "Paul Gilmartin" <0014e0e4a59b-dmarc-requ...@listserv.uga.edu>
Sent: Friday, August 03, 2018 3:09 AM
A principal use of EX is to be able to use a register mask to modify the
target. CDC 3800 had a clever alternative to this, a modify-next-instruction
instruction (I forget what it was
I believe that some DEC assemblers allow local labels of
the form d$ where d is a digit from 0 to 9.
Local labels need to be unique between any two normal labels.
References to them would, then, only work between those same labels.
-- glen
Knuth's ASSEMLER is called MIXAL, because it was designed for the
hypothetical machine MIX.
There are some tutorials on the web for MIX and MIXAL.
The local symbols of MIXAL are described here:
http://www.gnu.org/software/mdk/manual/html_node/Local-symbols.html#Local-symbols
Kind regards
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