Re: Help needed: small piece of assembler code for IRAF

On Sep 18 2024, Ole Streicher wrote:

> As IRAF is a 40-year old package, there was already some assembler that 
> was used ~35 years ago [2]:
>
>          .text
>          .globl  _zsvjmp_
>
>          JMPBUF	=       4
>          STATUS  =       8
>
> _zsvjmp_:			|# CALL ZSVJMP (JMPBUF, STATUS)
>          movl    sp@(JMPBUF),a0	|# set A0 to point to jmp_buf
>          movl    sp@(STATUS),a1	|# A1 = status variable
>          movl    a1,a0@		|# JB[0] = addr of status variable
> 	clrl	a1@		|# return zero status
> 	addql	#4,sp@(JMPBUF)	|# skip first cell of jmp_buf
>          jmp     _setjmp		|# let setjmp do the rest.
>
> However, just including this does not work because assembler syntax 
> changed [3].

Registers need to be prefixed with %, and assembler labels for C symbols
do not have a _ prefix.