> Recently i am working on the atomic support for RTEMS. Our basic idea is to > integrate the C11 atomic API into RTEMS. we have integrated the > stdatomic.h into newlib which is used by RTEMS. And when we test the > atomic ops on LEON3 platform (an important platform for RTEMS to test and > verify SMP support) it posted that there is no defined functions like > "__atomic_fetch_add_xx". And this is because of SPARC V7-V8 lacks of > compare and swap instruction., GCC also does not support those build in > ops. But for LEON3 it is a special case, it has its own casa instruction > to support compare_and_swap function. So i wonder whether gcc can consider > support LEON3 build in atomic ops.
Sure, patches to that effect are welcome. This will need to be coordinated with binutils because the assembler will very likely reject the instructions if it is passed -Av8 as is currently done for LEON/LEON3. As a matter of fact, I just installed a patch to add basic LEON3 support on the trunk so almost everything is already there as far as the compiler is concerned. -- Eric Botcazou
