ARM Cortex R4F - Manual (Page 39)

Introduction
ARM DDI 0363E Copyright © 2009 ARM Limited. All rights reserved. 1-18
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Figure 1-4 Cortex-R4F Issue and Execution pipeline stages
The names of the common pipeline stages and their functions are:
Iss Register read and instruction issue to execute stages.
Ex Execute stages.
Wr Write-back of data from the execution pipelines.
Ret Instruction retire.
The names of the load/store pipeline stages and their functions are:
DC1 First stage of data memory access.
DC2 Second stage of data memory access.
The names of the floating point pipeline stages and their functions are:
F0 Floating point register read.
F1 First stage of floating point execution.
F2 Second stage of floating point execution.
Fwr Floating point writeback.
The pipeline structure provides a pipelined 2-cycle memory access and single-cycle load-use
penalty. This enables integration with slow RAM blocks and maintains good CPI at reasonable
frequencies.
Register
read,
address
generation,
and
instruction
issue
EX1
DC1
Exception flush and mispredicted
indirect branches
F0
EX1
DC2
F1 F2
Load/store
pipeline
Data
processing
pipeline
Floating point
pipeline
Iss Ex1 Ex2 Wr Ret
Fwr
Mispredicted direct branches
Wr