Andi Kleen <[EMAIL PROTECTED]> writes: > Ian Lance Taylor <[EMAIL PROTECTED]> writes: > > > > What do people think of this patch? This seems to fix the problem > > case without breaking Michael's case. It basically avoids store > > speculation: we don't write to a MEM unless the function > > unconditionally writes to the MEM anyhow. > > I'm not sure "function" is a good area to check here. It might well be that > a function has parts where it is ok to change memory (because a lock is hold) > and another part where this is not true. But your check would > mix them both togeter.
The second version of my patch would not do that, because the lock operation would be a memory barrier. > Basic block (or rather super block without function calls or memory barriers) > would be better. Basic block would be useless, since there are already two basic blocks involved. My second patch looks through dominated blocks and stops at a memory barrier. So pretty much what you suggest. Ian
