Path: utzoo!utgpu!water!watmath!clyde!att-cb!att-ih!alberta!ubc-cs!ubc-bdcvax!charles From: charles@ubc-bdcvax.UUCP Newsgroups: comp.unix.wizards Subject: Re: Hand Assembling for the VAX.. Message-ID: <298@ubc-bdcvax.UUCP> Date: 1 Apr 88 04:45:21 GMT Sender: charles@ubc-bdcvax.UUCP Lines: 21 Nf-ID: #R:e:-861000:ubc-bdcvax:42100001:000:1083 Nf-From: ubc-bdcvax!charles Mar 31 20:45:00 1988 >/***** 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: or Internet: charles@bdc.ubc.ca {decvax!ihnp4!alberta,watmath,uw-beaver}!ubc-vision!ubc-bdcvax!charles