Extended mnemonics of condition register logical instructions

The extended mnemonics of condition register logical instructions are available in POWER® family and PowerPC®.

Extended mnemonics of condition register logical instructions are available in POWER® family and PowerPC®. These extended mnemonics are in the com assembly mode. Condition register logical instructions can be used to perform the following operations on a given condition register bit.

Set bit to 1.
Clear bit to 0.
Copy bit.
Invert bit.

The extended mnemonics shown in the following table allow these operations to be easily coded.

Table 1. Condition Register Logical Instruction Extended Mnemonics
Extended Mnemonic	Equivalent to	Meaning
crset bx	creqv bx, bx, bx	Condition register set
crclr bx	crxor bx, bx, bx	Condition register clear
crmove bx, by	cror bx, by, by	Condition register move
crnot bx, by	crnor bx, by, by	Condition register NOT

Since the condition register logical instructions perform the operation on the condition register bit, the assembler supports expressions in all input operands. When using a symbol name to indicate a condition register (CR) field, the symbol name should be multiplied by four to get the correct CR bit, because each CR field has four bits.

Examples

To clear the SO bit (bit 3) of CR0:
```
crclr   so
```
This is equivalent to:
```
crxor 3, 3, 3
```

To clear the EQ bit of CR3:


crclr   4*cr3+eq

This is equivalent to:


crxor   14, 14, 14

To invert the EQ bit of CR4 and place the result in the SO bit of CR5:
```
crnot   4*cr5+so, 4*cr4+eq
```
This is equivalent to:
```
crnor   23, 18, 18
```