2-58
MPC7400 RISC Microprocessor Users Manual
Instruction Set Summary
2.3.4.4.2 Branch Instructions
Table 2-39 lists the branch instructions provided by the PowerPC processors. To simplify
assembly language programming, a set of simpliTed mnemonics and symbols is provided
for the most frequently used forms of branch conditional, compare, trap, rotate and shift,
and certain other instructions. See Appendix F, òSimpliTed Mnemonics,ó in
The
Programming Environments Manual
for a list of simpliTed mnemonic examples.
2.3.4.4.3 Condition Register Logical Instructions
Condition register logical instructions, shown in Table 2-40, and the Move Condition
Register Field (
mcrf
) instruction are also deTned as ow control instructions.
Note that if the LR update option is enabled for any of these instructions, the PowerPC
architecture deTnes these forms of the instructions as invalid.
2.3.4.4.4 Trap Instructions
The trap instructions shown in Table 2-41 are provided to test for a speciTed set of
conditions. If any of the conditions tested by a trap instruction are met, the system trap type
program exception is taken. For more information, see Section 4.6.7, òProgram Exception
(0x00700).ó If the tested conditions are not met, instruction execution continues normally.
Table 2-39. Branch Instructions
Name
Mnemonic
Syntax
Branch
b (ba bl bla)
target_addr
Branch Conditional
bc (bca bcl bcla)
BO
,
BI,target_addr
Branch Conditional to Link Register
bclr (bclrl)
BO
,
BI
Branch Conditional to Count Register
bcctr (bcctrl)
BO
,
BI
Table 2-40. Condition Register Logical Instructions
Name
Mnemonic
Syntax
Condition Register AND
crand
crb
D
,crb
A
,crb
B
Condition Register OR
cror
crb
D
,crb
A
,crb
B
Condition Register XOR
crxor
crb
D
,crb
A
,crb
B
Condition Register NAND
crnand
crb
D
,crb
A
,crb
B
Condition Register NOR
crnor
crb
D
,crb
A
,crb
B
Condition Register Equivalent
creqv
crb
D
,crb
A
,
crb
B
Condition Register AND with Complement
crandc
crb
D
,crb
A
,
crb
B
Condition Register OR with Complement
crorc
crb
D
,crb
A
,
crb
B
Move Condition Register Field
mcrf
crf
D
,crf
S