ARM developers had already been working on their 64-bit ARM / AArch64 compiler port, which was officially approved just days ago. The latest ARM open-source compiler patch is ARMv8 in the AArch32 port with basic functionality.
This work basically allows for a armv8-a target for setting -march=armv8-a when building out software for Linux on ARM. Compared to ARMv7 on 32-bit ARM, the ARMv8 revision supports new NEON cryptographic functionality.
The ARMv8 GCC patch is currently sitting on the patches mailing list.