Scheduler Implementing Dependency Matrix Having Restricted Entries

A computer-implemented method, comprising:

• receiving, by a scheduler of a processing device, an instruction decoded by the processing device;
• determining, by the scheduler, that the decoded instruction qualifies for allocation as a restricted reservation station (RS) entry type in a dependency matrix maintained by the scheduler;
• identifying, by the scheduler, RS entries in the dependency matrix that are free for allocation;
• allocating, by the scheduler, one of the identified free RS entries with information of the decoded instruction in the dependency matrix;
• and
• updating, by the scheduler, at least one of a row or a column of the dependency matrix corresponding to the claimed RS entry with source dependency information of the decoded instruction, wherein the restricted RS entry comprises at least one of a row in the dependency matrix without a corresponding column in the dependency matrix or a column in the dependency matrix without a corresponding row in the dependency matrix.

A system, comprising:

• a memory to store a dependency matrix comprising entries indicative of a dependency status of a plurality of instructions, wherein the dependency matrix comprises one or more restricted entries with at least one of a row entry in the dependency matrix and without a corresponding column entry in the dependency matrix or a column entry in the dependency matrix and without a corresponding row entry in the dependency matrix;
• and
• a scheduler communicably coupled to the memory, the scheduler to:
• broadcast an identifier (ID) of an instruction that is scheduled to one or more instructions awaiting scheduling and tracked by the scheduler using the matrix;
• and
• update one or more of the entries in the dependency matrix matching the identifier of the instruction.

A non-transitory machine-readable storage medium including data that, when accessed by a processing device, cause the processing device to perform operations comprising:

• tracking, by a scheduler of the processing device, one or more instructions awaiting scheduling via a dependency matrix comprising entries indicative of a dependency status of the one or more instructions and comprising one or more restricted entries with at least one of a row entry in the dependency matrix and without a corresponding column entry in the dependency matrix or a column entry in the dependency matrix and without a corresponding row entry in the dependency matrix;
• broadcasting, by the scheduler, an identifier (ID) of an instruction that is scheduled, the ID broadcasted to the one or more instructions in the dependency matrix;
• and
• updating, by the scheduler, one or more of the entries in the dependency matrix matching the ID of the instruction.