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vasm - symbols in label names?

I have some unrolled loops that look a bit like this, with the loop body in a macro 'TDMR1COL'.

Code:

move.l      .td_mr1_jt(pc,d5.w),a5

jmp         (a5)



.td_mr1_jt:

dc.l        .td_mr1_1

dc.l        .td_mr1_2

dc.l        .td_mr1_3

dc.l        .td_mr1_4

dc.l        .td_mr1_5

dc.l        .td_mr1_6

dc.l        .td_mr1_7

dc.l        .td_mr1_8



TDMR1COL:    MACRO

.td_mr1_\1: ...

ENDM



TDMR1COL    8

TDMR1COL    7

TDMR1COL    6

TDMR1COL    5

TDMR1COL    4

TDMR1COL    3

TDMR1COL    2

 TDMR1COL    1

Is there a way to set up something like this with a REPT (or two) in vasm? I can't see a way to construct the .td_mr1_X labels automatically by including a symbol generated from the repeat count in a label name, either a REPTN or a SET-value.

I'd be really interested in knowing if this is possible as well. I've not found any way to do it, but that doesn't mean it can't be done ;)

It is possible, although not in a very elegant way. If you look into the mot-syntax documentation you see that the special macro argument

\<symbolname>

is supported (same syntax as Devpac?). It will insert the current decimal value of the absolute symbol with that name.

So you can solve the problem by defining a helper-macro, like

Code:

TDMR1COL_REPTN  macro

CNT     set     8-REPTN

        TDMR1COL \<CNT>

        endm

Then run your REPT-loop with it:

Code:

        rept    8

        TDMR1COL_REPTN

        endr

This is pretty much what I used to do in Devpac.

I've put some tabs in your code and added an 'rts' into your macro:

Code:

        moveq        #4,d5        ; Just so this is within the table.



        move.l      .td_mr1_jt(pc,d5.w),a5

        jmp         (a5)



.td_mr1_jt:

        dc.l        .td_mr1_1

        dc.l        .td_mr1_2

        dc.l        .td_mr1_3

        dc.l        .td_mr1_4

        dc.l        .td_mr1_5

        dc.l        .td_mr1_6

        dc.l        .td_mr1_7

        dc.l        .td_mr1_8



TDMR1COL    MACRO

.td_mr1_\1:        rts

ENDM



        TDMR1COL    8

        TDMR1COL    7

        TDMR1COL    6

        TDMR1COL    5

        TDMR1COL    4

        TDMR1COL    3

        TDMR1COL    2

        TDMR1COL    1

Saved it as "test.s" then assembled this with:

Code:

vasmm68k_mot -devpac -Fhunkexe test.s -o test

EDIT: Actually, the "-devpac" option isn't necessary as it still assembles and works without it

And get the following result:

Code:

vasm 1.8j (c) in 2002-2020 Volker Barthelmann

vasm M68k/CPU32/ColdFire cpu backend 2.3n (c) 2002-2020 Frank Wille

vasm motorola syntax module 3.14c (c) 2002-2020 Frank Wille

vasm hunk format output module 2.13 (c) 2002-2020 Frank Wille



CODE(acrx2):                  56 bytes

Which results in a binary file "test", which runs successfully and exits.

Ah, of course!
For some reason I thought REPTN couldn't be used as a macro argument :confused

Good to know it can.

Quote:

Originally Posted by roondar (Post 1474318)

For some reason I thought REPTN couldn't be used as a macro argument :confused

It can't. The text given as macro arguments is never interpreted in any way, but just pasted into the macro source text at the positions marked with \1, \2, etc...

So when you call the original macro as

TDMR1COL REPTN

, you will get eight times the same label

.td_mr1_REPTN:

as REPTN is regarded being part of the label name.

Therefore you have to use

\<symbol>

within the macro to make the parser insert the current symbol's value instead. It has nothing to do with any argument given to the macro.

EDIT: Maybe I confused you by designating

\<symbol>

as "special macro argument", like all other codes starting with '\' within a macro. These escape codes always insert some text, but only in some cases this text will be directly taken from an argument given to the macro. Refer to the documentation.

I see, I misread that macro.
So, am I then correct in saying that the workaround is that you set a symbol to a value based on REPTN in a macro and then you expand that symbol in the same macro?

Quote:

Originally Posted by roondar (Post 1474334)

So, am I then correct in saying that the workaround is that you set a symbol to a value based on REPTN in a macro and then you expand that symbol in the same macro?

Exactly. Of course, you can also use REPTN directly, when its value suits you. :)
EDIT: Within

\<REPTN>

of course...

Thanks, a clever trick. I have other loops like this with 24 and more iterations so it will be nice to tidy those up!