2-42
MPC7400 RISC Microprocessor Users Manual
Instruction Set Summary
2.3.3 Instruction Set Overview
This section provides a brief overview of the PowerPC instructions implemented in the
MPC7400 and highlights any special information with respect to how the MPC7400
implements a particular instruction. Note that the categories used in this section correspond
to those used in Chapter 4, òAddressing Modes and Instruction Set Summary,ó in
The
Programming Environments Manual
. These categorizations are somewhat arbitrary and are
provided for the convenience of the programmer and do not necessarily reect the PowerPC
architecture speciTcation.
Note that some instructions have the following optional features:
¥
¥
CR UpdateThe dot (
.
) sufTx on the mnemonic enables the update of the CR.
Overow optionThe
o
sufTx indicates that the overow bit in the XER is enabled.
2.3.4 PowerPC UISA Instructions
The PowerPC UISA includes the base user-level instruction set (excluding a few user-level
cache control, synchronization, and time base instructions), user-level registers,
programming model, data types, and addressing modes. This section discusses the
instructions deTned in the UISA.
2.3.4.1 Integer Instructions
This section describes the integer instructions. These consist of the following:
¥
¥
¥
¥
Integer arithmetic instructions
Integer compare instructions
Integer logical instructions
Integer rotate and shift instructions
Integer instructions use the content of the GPRs as source operands and place results into
GPRs, the XER register, and condition register (CR) Telds.
2.3.4.1.1 Integer Arithmetic Instructions
Table 2-19 lists the integer arithmetic instructions for the PowerPC processors.
Table 2-19. Integer Arithmetic Instructions
Name
Mnemonic
Syntax
Add Immediate
addi
r
D
,r
A,SIMM
Add Immediate Shifted
addis
r
D
,r
A,SIMM
Add
add
(
add. addo addo.
)
r
D
,r
A
,r
B
Subtract From
subf
(
subf. subfo subfo.
)
r
D
,r
A
,r
B
Add Immediate Carrying
addic
r
D
,r
A,SIMM
Add Immediate Carrying and Record
addic.
r
D
,r
A,SIMM