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Re: GCC in-line assembly and the removal of -mcx16
On 26/05/17 12:51, Alexander Monakov wrote:
> Note that the behavior with regards to __sync builtins (as opposed to __atomic)
> remains unchanged, so uses of __sync_val_compare_and_swap can emit cmpxchg16 if
> -mcx16 is given on the command line.
Just as a note to any future readers, although I may well be wrong, I
think this is only true for GCC 4.8.0 onwards, with the introduction of
the 128 bit types.
Prior to that, the only option is inline assembly.