Maclhwsu - IBM PPC440X5 CPU Core User Manual

Preliminary

maclhwsu

Multiply Accumulate Low Halfword to Word Saturate Unsigned
maclhwsu RT, RA, RB
maclhwsu. RT, RA, RB
maclhwsuo RT, RA, RB
maclhwsuo. RT, RA, RB
4
0 6
prod (RA)
0:31 16:31
temp prod + (RT)
0:32 0:31
32
(RT) (temp
1:32
The low-order halfword of RA is multiplied by the low-order halfword of RB. The unsigned product is summed
with the contents of RT.
If the unsigned sum can be represented in 32 bits, then RT is updated with the low-order 32 bits of the
unsigned sum.
If the unsigned sum cannot be represented in 32 bits, then RT is updated with a value which is "saturated" to
the maximum representable value of 2
Registers Altered
• RT
• CR[CR0] if Rc contains 1
• XER[SO, OV] if OE contains 1
Architecture Note
This instruction is implementation-specific and programs which use this instruction may not be portable to
other PowerPC Book-E implementations. See Instruction Set Portability on page 250.
instrset.fm.
September 12, 2002
OE=0, Rc=0
OE=0, Rc=1
OE=1, Rc=0
OE=1, Rc=1
RT RA
11
(RB) unsigned
16:31
temp )
0
32
– 1.
Multiply Accumulate Low Halfword to Word Saturate Unsigned
PPC440x5 CPU Core User's Manual
RB OE
16 21 22
maclhwsu
460 Rc
31
Page 355 of 589