Re: [9fans] FP register usage in Plan9 assembler

[Brantley Coile <brantleycoile@me.com>]

Which plan 9 assembler uses right to left argument assignments, or compare argument order? I was not aware of inconsistency in syntax between assemblers. 

Maybe there is confusion between the use, in the different posts, between the macro architecture and the versions of the assembler, referred to as architecture. 

Or the confusion is about what Plan 9 is meant to be. The idea was to have a single system made of many different machines of a diverse set of architectures. A single system would have a single assembly language. The architectures are still different, but as much as possible the accidental differences between the assembly languages of the processor manufacturers are eliminated. The idea is not just to be a cross compiling system for embedded targets or is it to be a single machine system that ran on different hardware, but to be a single system running on a cloud of machines, to borrow some marketing jargon.

To that end, the Plan 9 syntax is fine for teaching assembler. And so doing, a person is better able to write good C code. The only disadvantage is when learning the assembler one has to translate front the manufacturer's documentation and the Plan 9 standard syntax. 

  Brantley Coile

Sent from my iPad

> On Feb 4, 2016, at 5:08 AM, Aram Hăvărneanu <aram.h@mgk.ro> wrote:
> 
>> On Wed, Feb 3, 2016 at 4:24 PM, erik quanstrom <quanstro@quanstro.net> wrote:
>> i love the consistency from one architecture to another.
> 
> Just like how different architectures use different order for CMP
> arguments. Very consistent.
> 
> Or just how some architectures use typed registers, and some use
> different-sized instruction variants.
> 
> Or just how most instructions use left-to-right dataflow order, some
> instructions use right-to-left.
> 
> I could go on. Plan 9 assembly is nice because it looks mostly the
> same, and the simple addressing modes are mostly consistent, but it's
> far from being really consistent between architectures.
> 
> -- 
> Aram Hăvărneanu
>