Hi
  is there in FPC a membar instruction, like #StoreLoad macro or smp_mb();

and second need instruction is NOOP

Darek

Dariusz Mazur wrote

Hi is there in FPC a membar instruction, like #StoreLoad macro or smp_mb();

ReadBarrier, ReadDependencyBarrier, ReadWriteBarrier, WriteBarrier; in system unit.

and second need instruction is NOOP

Don't know about this one, can't you use a do nothing loop?

Micha

Micha Nelissen pisze:

thx

in spin-lock there is NOOP used, I think that is instruction, that every processor do nothing but not avoid (duration is very small but not zero)

Darek

Dariusz Mazur wrote

> Don't know about this one, can't you use a do nothing loop? > in spin-lock there is NOOP used, I think that is instruction, that every processor do nothing but not avoid (duration is very small but not zero)

Why do you use a NOP in a spin-lock?

Micha

Micha Nelissen pisze:

its only exaple form sparc manual, I need (I want to test) it to in my FIFO algo.

form SPARCV9.PDF:

LockWithLDSTUB(lock)
retry:
ldstub [lock],%l0
tst %l0
be out
nop
loop:
ldub [lock],%l0
tst %l0
bne loop
nop
ba,a retry
out:
membar #LoadLoad | #LoadStore
UnLockWithLDSTUB(lock)
membar #StoreStore !RMO and PSO only
membar #LoadStore !RMO only
stub %g0,[lock]

Example 7---Lock and Unlock Using LDSTUB

Darek

Dariusz Mazur wrote

be out nop

Here it's needed because of branch delay slot. You don't need it in pascal code (only when coding custom assembly), compiler will take care of that automatically.

Micha