On Wed, May 18, 2016 at 04:10:37PM +0100, David Howells wrote: > There are some advantages to using ISO C++11 atomics: > > (1) The compiler can make use of extra information, such as condition > flags, that are tricky to get out of inline assembly in an efficient > manner. This should reduce the number of instructions required in > some cases - such as in x86 where we use SETcc to store the condition > inside the inline asm and then CMP outside to put it back again. > > Whilst this can be alleviated by the use of asm-goto constructs, this > adds mandatory conditional jumps where the use of CMOVcc and SETcc > might be better. Supposedly gcc-6.1 has cc-output which makes this go away. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
