Dependency scheduling for control stream in parallel processor

A non-transitory computer-readable medium having instructions stored thereon that include:

• a control stream that includes kernels and commands, wherein instructions of the kernels are executable by one or more graphics processors to perform one or more operations, wherein the control stream includes multiple substreams;
• wherein multiple ones of the substreams are for fetching and parsing by respective assigned substream processors in a set of substream processors;
• and
• wherein a first substream includes a neighbor barrier command that identifies a second substream, wherein the neighbor barrier command indicates to prevent a first substream processor to which the first substream is assigned from proceeding past the neighbor barrier command until a most-recently-completed command, from a second substream processor to which the second substream has assigned, meets a threshold.

A non-transitory computer readable storage medium having stored thereon design information that specifies a design of at least a portion of a hardware integrated circuit in a format recognized by a semiconductor fabrication system that is configured to use the design information to produce the circuit according to the design, including:

• graphics processor circuitry configured to execute instructions specified by kernels;
• one or more storage elements configured to store a control stream that includes kernels and commands, wherein the control stream includes multiple substreams;
• barrier clearing circuitry;
• and
• a set of multiple substream processors, wherein ones of the substream processors are configured to:
• fetch and parse portions of the control stream corresponding to an assigned sub stream;
• in response to a neighbor barrier command in the assigned substream that identifies another substream, communicate the identified other substream to the barrier clearing circuitry;
• wherein the barrier clearing circuitry is configured to determine whether to allow the assigned substream to proceed past the neighbor barrier command based on communication of a most-recently-completed command from of a substream processor to which the other substream is assigned.