IBM SA14-2339-04 Personal Computer User Manual


 
9-36 PPC405 Core User’s Manual
cmpl
Compare Logical
cmpl
Compare Logical
c
0:3
4
0
if (RA) (RB) then c
0
1
if (RA) (RB) then c
1
1
if (RA) (RB) then c
2
1
c
3
XER[SO]
n
BF
CR[CRn]
c
0:3
The contents of register RA are compared with the contents of register RB, using a 32-bit unsigned
compare.
The CR field specified by the BF field is updated to reflect the results of the compare and the value of
XER[SO] is placed into the same CR field.
If instruction bit 31 contains 1, the contents of CR[CR0] are undefined.
Registers Altered
CR[CR
n
] where
n
is specified by the BF field
Invalid Instruction Forms
Reserved fields
Programming Notes
The PowerPC Architecture defines this instruction as cmpl BF,L,RA,RB, where L selects operand
size for 64-bit PowerPC implementations. For all 32-bit PowerPC implementations, L = 0 is required
(L = 1 is an invalid form); hence for PPC405 core, use of the extended mnemonic cmplw BF,RA,RB
is recommended.
Architecture Note
This instruction is part of the PowerPC User Instruction Set Architecture.
cmpl BF, 0, RA, RB
31 BF RA RB 32
069111621 31
Table 9-12. Extended Mnemonics for cmpl
Mnemonic Operands Function
Other Registers
Altered
cmplw [BF,] RA, RB Compare Logical Word.
Use CR0 if BF is omitted.
Extended mnemonic for
cmpl BF,0,RA,RB
<
u
>
u
=