ARB_gpu_shader_int64 Sounds Like It's Ready For Mesa
In addition to the big Mesa shader cache patch series hitting the mailing list over night, Ian Romanick at Intel sent out another big patch series: his revised work on ARB_gpu_shader_int64 support.
Last month Intel published the original INT64 patches for Mesa while now it's been fixed up and it looks like it might soon be ready for mainline. The GL_ARB_gpu_shader_int64 extension is about adding 64-bit integer support for OpenGL shaders.
The new 50 patches for Mesa can be found on Mesa-dev. The revised patches no longer carry any INT64 changes for Gallium3D, which will need to be picked up separately by any other interested developer. Enabling this support in Mesa comes in at just under 5,000 lines of code. The ARB_gpu_shader_int64 Mesa support in the Intel driver is for Broadwell hardware and newer.