push&pop

[Yamakaky]

It may be cool to add a pop reg/push reg/peek reg syntaxe. It doesn't follow the specs, but does .* do ?

[HerobrinesArmy]

So ,push and .pop?

[Yamakaky]

no, like that :

push A
set A, 42
pop A

[L3nn0x]

And pick 2,A too ?

[Yamakaky]

Oh yes, but it looks a bit less nice, it's more like add or set.

[Yamakaky]

After checking the doc, pick and peek may not be a good idea. When you use push/pop, there is one possible action (move the arg from/to the stack). With peek (and pick), you can do set A, PEEK or set PEEK, A. How do you translate peek A ?

[Lucus16]

If you want to have such pop and push instructions, you really should be doing it with macros, as soon as that is supported.

[Yamakaky]

Maybe, but there is still problems with the 'real' pop/push. Ex : you can't do .define pop(X) set X, pop… In fact yes, we can ! I was considering the actual syntax (.define push set push,), which isn't working (confusing with, for ex, set push, A), but if we use brackets, there's no problem !

[HerobrinesArmy]

I don't plan for DevCPU to have any built-in support for specific artificial opcode mnemonics. I can go on and on about the reasons for not doing that, but I've done it so many time before that the words have lost all meaning. If someone wants artificial opcode mnemonics, they can look to see if a define will give them what they need. Here's some people might like to use:

#define push set push
#define jmp set pc
#define ret set pc pop

Admittedly, pop is a little more difficult, though we'll see what macro features I end up with in DevCPU that might accommodate that. You'll probably be able to do:

#macro pop(dest)
set dest pop
#endmacro

or something like that, in which case, I'll try to make parentheses optional in the macro use, so people who defined the above macro can use it by just typing:

pop A

or what have you.

I'm not entirely opposed to adding convenience directives like .jmp, .push, .pop, etc., that accomplish the same thing, but I don't believe you'll ever seen built-in support for specific artificial opcode mnemonics.

[Yamakaky]

You're right.

.define push set push is dangerous, for ex if somebody wants to write push with his default meaning. Macro is better.

[HerobrinesArmy]

Wait. Scratch everything I just wrote. Push and pop are stack accessors defined by the DCPU-16 specification. You'd screw everything up if you #define'd them. Macros would probably have the same problem. My personal suggestion is to use the language as it is specified. Then again, I'm old-fashioned.

[Yamakaky]

^^
That what I was saying. Macros, with brackets, may work.

[HerobrinesArmy]

That's the thing... I wasn't planning to require parentheses or anything in macro usage. So you'll be able to use a macro by writing

mymacro(a, b)

or simply

mymacro a b

Consequently, trying to make a macro named 'push' would have the same problem as making a define for it, since, for a macro defined like this:

.macro push(v)
set push v
.endmacro

a normal use of push:

set push, z

would still get replaced by the macro.

Well...it might work if I make DevCPU macros only work as the start of a line, which I probably should and probably would. We'll see, I suppose.

I would strongly advise against using names that already mean something in the language and against relying on a very specific behavior of the assembler to avoid issues. I'm not going to do anything to try to stop you from doing that, of course, but I'm also not likely to take it into consideration when I'm designing these features, so DevCPU may or many not end up accommodating those push/pop macros. It will depend how I implement macros.

My advice, to avoid problems if you go the macro route, would be to use a different name. Perhaps macros named "Empiler" and "Dépiler". =P

[Yamakaky]

^^

[L3nn0x]

I think macro should only be used with parentheses, so it allows them to not be at the start of the line. But it's just my opinion. Even though a conditionnal macro could be of use at the end of a command (I don't have the slightest idea how it could be however).

[Yamakaky]

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