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Re: Moving VAX into 21 century :-)



On 2019-09-01 06:01, Mouse wrote:
I can't remember.  Does CALL really align the stack?
Yes, and yes.  The alignment (2 bits) is part of the generated stack
frame.
And, sorry for asking instead of trying to read the documentation,
this alignment is not done in general for the stack?

Right; it is not.  The VAX is about as misalignment-tolerating as
architectures get; there are extremely few pieces of it where anything
needs any alignment at all.  You can `align' your stack to an odd
address and, in general, all that will happen is you'll pay a bit of a
speed penalty on some implementations.

Yes, which is why I was a bit surprised that it did do alignment in the CALLx instructions. But so it did.

  Johnny

--
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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