Chapter One Introduction to Pipelined
Processors
Principle of Designing Pipeline Processors
(Design Problems of Pipeline Processors)
Internal Data Forwarding and Register Tagging
Internal Forwarding and Register Tagging
• Internal Forwarding: It is replacing unnecessary memory accesses by register-to-register transfers.
• Register Tagging: It is the use of tagged registers for exploiting concurrent activities among multiple ALUs.
Internal Forwarding
• Memory access is slower than register-to-register operations.
• Performance can be enhanced by eliminating unnecessary memory accesses
Internal Forwarding
• This concept can be explored in 3 directions:1.Store – Load Forwarding2.Load – Load Forwarding3.Store – Store Forwarding
Store – Load Forwarding
Load – Load Forwarding
Store – Store Forwarding
Example
EXAMPLE
Example
EXAMPLE