Macchw - IBM PPC440X5 CPU Core User Manual

Preliminary

macchw

Multiply Accumulate Cross Halfword to Word Modulo Signed
macchw RT, RA, RB
macchw. RT, RA, RB
macchwo RT, RA, RB
macchwo. RT, RA, RB
4
0 6
prod (RA)
0:31 16:31
temp prod + (RT)
0:32 0:31
(RT) temp
1:32
The low-order halfword of RA is multiplied by the high-order halfword of RB. The signed product is summed
with the contents of RT and RT is updated with the low-order 32 bits of the signed sum.
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) signed
0:15
Multiply Accumulate Cross Halfword to Word Modulo Signed
PPC440x5 CPU Core User's Manual
RB OE
16 21 22
macchw
172 Rc
31
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