tech-kern archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: mutexes, locks and so on...

Just a note to avoid having incorrect information in the archives
without a correction.  I wrote:

> [%] It occurs to me, the VAX's BBSSI and BBCCI _are_ CAS, just
> restricted to a one-bit-wide operand (and with the data-to-swap-in
> specified by choice of instruction rather than an operand).

This is false.  CAS, as the term is normally used, turns out to be not
the compare-and-swap the acronym expands to but
compare-and-conditionally-swap.  However, BBSSI and BBCCI always
perform the write.

/~\ The ASCII                             Mouse
\ / Ribbon Campaign
 X  Against HTML      
/ \ Email!           7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B

Home | Main Index | Thread Index | Old Index