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Asman
09 February 2006, 17:45
So, few days ago i launch old editor emacs18.59 and in drawer amiga/contribution/kaiser find little program pub. This simply program just open public screen, but on my amiga without coprocessor program generate guru. I find error ( few coprocessor instruction in code) and program works.

But one thing i dont' understand. In code I find follow instruction
MOVEM.L ,-(A7) ;$48E70000
I check with Asm-One, also check with bdebeg. But Ira with option -a show
MOVEM.L (NOREG!),-(A7) ;094A: 48E70000

Question, What this instruction do ? :confused .Maybe only eat stack place :crazy . Hmm, any ideas ?

Asman

Galahad/FLT
09 February 2006, 22:56
Its not anything. Someones forgotten to put the rest of the instruction data in there.

Photon
10 February 2006, 00:50
Yeah, IIRC the second word contain 16 bits of data where each bit set is one register pushed onto the stack. If no bits are set, no register is pushed, so it doesn't compute.

NOB
10 February 2006, 17:50
movem.l,-(a7) has no sense.


MINI_MOVEM TUT:cool

lea $2000,A2
move.l #1,d1 ;d1:=1
move.l #2,d2 ;d2:=2
move.l #$14,a4 ;a4:=$14
movem.l d2/a4/d1,-(a2) ;a2:=a2-3*4=$1ff4

*memory allocation
*$1ff4 $1ff5 $1ff6 $1ff7 $1ff8 $1ff9 $1ffa $1ffB $1ffC $1ffd $1ffe $1fff
*\---------d1---------/ \----------d2-------/ \----------a4--------/
*the dataregisters will always be stored at the lower mem position
*the registers with higher numbers are always stored at the higher mem position

movem.l (a2),d6/d5 ;d5:=1;d6:=2
movem.l (a2)+,d7 ;a2:=a2+4 = $1ff8; d7:=1

Asman
10 February 2006, 19:00
movem.l,-(a7) has no sense.

Thats right has no sense but i find this instruction in program pub which is joined to archive of emacs18.59. And this is funny :spin

Another thing. Write in for example Asm-One dc.l $45e70000 and debug that, you find movem.l ,-(a7). But try write movem.l ,-(a7) . And that is really funny. :spin

Thanks for answers.

Gretz.

Photon
10 February 2006, 23:00
I have really bad memories of emacs... trying to repress them ...