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c++ Programming Glossary: barrierhttp://stackoverflow.com/questions/10587598/simd-prefix-sum-on-intel-cpu suma ithread 1 pass1_SSE a start s start chunk #pragma omp barrier #pragma omp single float tmp 0 for int i 0 i nthreads 1 i.. ithread offset2 pass2_SSE s start offset chunk #pragma omp barrier offset2 s start chunk 1 delete suma share improve this answer..
How does the friend keyword (Class/Function) break encapsulation in C++? http://stackoverflow.com/questions/1093618/how-does-the-friend-keyword-class-function-break-encapsulation-in-c instead they naturally extend the encapsulation barrier what does it mean .. If a friend function breaks the encapsulation..
http://stackoverflow.com/questions/12878344/volatile-in-c11 from to x to be atomic nor does it require the memory barriers needed for non atomic reads writes to be properly ordered... memory access among different cores. These memory barriers allow two threads to communicate effectively. Merely reading.. enough the core that wrote the memory needs to issue a barrier and the core that's reading it needs to have had that barrier..
does presence of mutex help getting rid of volatile key word ? http://stackoverflow.com/questions/1616093/does-presence-of-mutex-help-getting-rid-of-volatile-key-word that are always confused. volatile threads locks memory barriers etc. volatile is used to tell the compiler to produce code.. In general not to optimize or take 'short cuts'. memory barriers supplied by mutexes locks etc as quoted from Herb Sutter in.. thus preventing evaluation or you call some asm memory barrier instructions ie that are wrapped in inline functions like __InterlockedCompareExchange..
Why is volatile not considered useful in multithreaded C or C++ programming? http://stackoverflow.com/questions/2484980/why-is-volatile-not-considered-useful-in-multithreaded-c-or-c-programming The solution to preventing reordering is to use a memory barrier which indicates both to the compiler and the CPU that no memory.. access may be reordered across this point . Placing such barriers around our volatile variable access ensures that even non volatile.. one allowing us to write thread safe code. However memory barriers also ensure that all pending reads writes are executed when..
A simple hello world NPAPI plugin for Google Chrome? http://stackoverflow.com/questions/2652034/a-simple-hello-world-npapi-plugin-for-google-chrome project It is a framework aiming at lowering the entry barrier to browser plugin development and already takes care of most..
Is 'volatile' needed in this multi-threaded C++ code? http://stackoverflow.com/questions/3612505/is-volatile-needed-in-this-multi-threaded-c-code a register cache in multi processor environments a memory barrier will also be required. Rather use the correct lock around the.. userside. They will also contain the necessary memory barriers. Volatile should only be used for memory mapped IO where multiple..
How to teach a crash course on C++? [closed] http://stackoverflow.com/questions/48496/how-to-teach-a-crash-course-on-c error messages and headers. This is actually quite a barrier and one that has to be breached early on. Apart from the language..
Creating a counter that stays synchronized across MPI processes http://stackoverflow.com/questions/4948788/creating-a-counter-that-stays-synchronized-across-mpi-processes the next one until there's no more work then you wait at a barrier or something and finalize. Once you have something like this..
Atomicity in C++ : Myth or Reality http://stackoverflow.com/questions/5002046/atomicity-in-c-myth-or-reality don't reorder your code. You can use compiler memory barrier for that. Low level atomic read and writes for x86 is described..
http://stackoverflow.com/questions/6319146/c11-introduced-a-standardized-memory-model-what-does-it-mean-and-how-is-it-g the compiler is likely to emit full blown memory barriers between every access here. But if your algorithm can tolerate.. like atomic types and the various flavors of memory barrier. So now you can write sophisticated high performance concurrent..
http://stackoverflow.com/questions/6866206/volatile-and-createthread don't. Most of the time what people really want are barriers also called fences and atomic instructions which are all compiler.. about other compilers. On some architectures like x86 a barrier is merely a way to prevent the compiler from reordering instructions... than you really wanted. It's not realistic. So we use barriers. They allow full optimization and only guarantee that the memory..
Memory model ordering and visibility? http://stackoverflow.com/questions/7461484/memory-model-ordering-and-visibility From what I can tell std memory_order_seq_cst inserts mem barrier while other only enforce ordering of the operations on certain.. 42 1234 random idx in array c c 11 mutex atomic memory barriers share improve this question If you like to deal with fences..
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