Mullw - IBM PPC440X5 CPU Core User Manual

mullw

Multiply Low Word
PPC440x5 CPU Core User's Manual
mullw
Multiply Low Word
mullw RT, RA, RB
mullw. RT, RA, RB
mullwo RT, RA, RB
mullwo. RT, RA, RB
31
0 6
prod (RA) (RB) signed
0:63
(RT) prod
32:63
The 64-bit signed product of register RA and register RB is formed. The least significant 32 bits of the result is
placed into register RT.
If the signed product cannot be represented in 32 bits and OE=1, XER[SO, OV] are set to 1.
Registers Altered
• RT
• CR[CR0] if Rc contains 1
• XER[SO, OV] if OE=1
Programming Note
The least significant 32 bits of the product are correct, regardless of whether register RA and register RB are
interpreted as signed or unsigned numbers. The overflow indication, however, is calculated specifically for a
64-bit signed product, and is dependent upon interpretation of the source operands as signed numbers.
Page 382 of 589
OE=0, Rc=0
OE=0, Rc=1
OE=1, Rc=0
OE=1, Rc=1
RT RA
11
RB OE
16 21 22
Preliminary
235 Rc
31
instrset.fm.
September 12, 2002