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Re: PIC question
Matt Thomas wrote:
On May 27, 2010, at 4:57 PM, Johnny Billquist wrote:
Martin Husemann wrote:
I'm new to vax asm and have not been fully assimilated, it seems - I have
some asm code that is not PIC and so when compiled into a .so dies due
to .text relocs. (Linked static it all works)
It does kindof Duff's device in asm - there is an unrolled loop starting
at .Loop and a jump with offset into the loop is calculated in %r5, then the
This causes a 32bit relocation for the .Loop address inside the
indirect jump with offset instructions.
What is the pic way to do this? Some trick? There doesn't seem to be a br +
register offset instruction.
Or along the lines of:
add .Loop - ., %r5
(but the .Loop-. is not accepted by gas)
Maybe a stupid solution, and I'm sure there is a more kosher one, but...
Bzzt. Can't do that to the PC register.
Ah! Darn. I had some nagging feeling that there might have been some
problem with that.
Its perfectly legal on the PDP-11 though. :-)
Hmm, so deferring won't work, but indexing will? That sounds weird...
Is that some limitation on gas then?
is the right answer.
or movab .Loop[%r5], %r5
But the first one is simpler.
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt%softjar.se@localhost || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
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