Check whether the GPU adapter runs plane (subgroup) operations

Advertising plane operations is not enough: the paravirtualised GPU of a macOS VM, as on the macos-15-intel GitHub runners, reports planes of 4 to 64 lanes but silently drops every dispatch that uses one. This launches a single plane reduction and checks the answer. The result is cached for the session.

Usage

rs_gpu_plane_ops()

Value

Boolean. TRUE when a GPU adapter is present and a plane reduction on it returns the plane width.