Hand Assembling for the VAX..

[charles at ubc-bdcvax.UUCP]

>/***** ubc-bdcvax:comp.unix.wizards / e!kishore /  4:10 am  Mar 19, 1988*/
>The question I had is : given a BRW instructionthat looks like
>BRW 1040 (Branch Word) what does the bit pattern look
>like? (assuming the 1040 is in hex). Also BRW seems to allow a maximum 
>displacement of 16 bits. What does one use to make bigger jumps? 
>	Also if I obtain the address of a function bar using nlist, the actual
>function seems to starts a few bytes after the value returned by nlist. These
>few bytes are probably used to hold some status info. I've been trying to 
>figure out the exact size of this area. 

At least, on a VAX 11/750 a routine actually starts 2 bytes after
the address given for its name by nlist(3).  Perhaps for larger than
16 bit range branches, you have to implement the branch with a jmp
and surround it with a small local negated logic jump.

--
Charles Mathieson, Biosciences Data Centre, University of British Columbia
UUCP:	<charles at ubc-bdcvax.UUCP> or     Internet: charles at bdc.ubc.ca
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