subfe
Subtract From Extended
Preliminary PPC440x5 CPU Core User’s Manual
instrset.fm.
September 12, 2002 Page 431 of 589
subfe
Subtract From Extended
(RT) ←¬(RA) + (RB) + XER[CA]
if
¬(RA) + (RB) + XER[CA] 2
32
– 1 then
XER[CA]
← 1
else
XER[CA]
← 0
The sum of the ones complement of register RA, register RB, and XER[CA] is placed into register RT.
XER[CA] is set to a value determined by the unsigned magnitude of the result of the subtract operation.
Registers Altered
•RT
• XER[CA]
• CR[CR0] if Rc contains 1
• XER[SO, OV] if OE contains 1
subfe RT, RA, RB OE=0, Rc=0
subfe. RT, RA, RB OE=0, Rc=1
subfeo RT, RA, RB OE=1, Rc=0
subfeo. RT, RA, RB OE=1, Rc=1
31 RT RA RB OE 136 Rc
0 6 11 16 21 22 31
>
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