CPU Models

• SimpleCPU - A good place to start learning about how to fetch, decode, execute, and complete instructions in M5.
• O3CPU - Specific documentation on how all of the pipeline stages work, and how to modify and create new CPU models based on it.
• Checker - Details how to use it in your CPU model.
• InOrder - Specific documentation on how all of the pipeline stages work, and how to modify and create new CPU models based on it.
  • Generic Pipeline Stages
  • Resource-Request Model
  • Resources and The Resource Pool
  • Pipeline Description
  • InOrder ToDo List

Supporting classes

• StaticInst - Used to hold static information and methods about specific binary instructions, such as addq's or subq's.
• DynInst - Used to hold dynamic information about instructions in the pipeline, such as the PC or predicted target.
• ThreadState - Used to store thread information that is generic across CPU models.
• SimpleThread - Used by simple CPU models to store architected state and provide the ThreadContext interface.

Interfaces

• ThreadContext - The ThreadContext class. Used to provide an interface for objects outside of the CPU to access the specific thread state.
• ExecContext - The ExecContext interface. An implicit interface that is used by the ISA in order to access the CPU's architected state.