Markus Schoepflin wrote:
Boris Gubenko wrote:
I'm a bit surprised you did not use __ATOMIC_EXCH_LONG in atomic_write32().
Two reasons. 1) I didn't think of it. 2) The guarantees given by volatile seemed OK.
Do you think I should change it to use __ATOMIC_EXCH_LONG?
I do. To see the difference, you can compare the code generated for foo() and bar() in x.cxx below. Note ldl_l/stl_c in bar(). x.cxx ----- #include <machine/builtins.h> void foo (volatile int *mem, int val) { *mem = val; } void bar (volatile int *mem, int val) { __ATOMIC_EXCH_LONG(mem, val); }
I'm also not sure why you decided to implement atomic_cas32() in asm language instead of using __CMP_STORE_LONG:
[...]
Because cas32 returns the old value, but __CMP_STORE_LONG does not.
I see. Thanks, Boris ----- Original Message ----- From: "Markus Schöpflin" <markus.schoepflin@comsoft.de> To: <boost@lists.boost.org> Sent: Friday, October 19, 2007 4:48 AM Subject: Re: [boost] [interprocess] Atomic ops supports for Alpha processors.
Boris Gubenko wrote:
Hi Markus,
Thank you for continuing to support Boost on Tru64.
I've asked Rich Peterson to review your implementation. I don't know yet when (and if) Rich will be able to do it.
That would be really great if someone knowledgeable could review the implementation.
I think
#elif defined(__osf__)
should be:
#elif defined(__osf__) && defined(__DECCXX)
to not break compilation with gcc.
You are right. I will add it.
I'm a bit surprised you did not use __ATOMIC_EXCH_LONG in atomic_write32().
Two reasons. 1) I didn't think of it. 2) The guarantees given by volatile seemed OK.
Do you think I should change it to use __ATOMIC_EXCH_LONG?
I'm also not sure why you decided to implement atomic_cas32() in asm language instead of using __CMP_STORE_LONG:
[...]
Because cas32 returns the old value, but __CMP_STORE_LONG does not.
Anyway, Rich is an expert in this stuff and, hopefully, he will be able to review your implementation.
Looking forward to it.
Markus
_______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost