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JCXZ
JUMP IF
ex
REGISTER ZERO
Operation: Flags Affected:
if (CX) = 0 then None
(lP)
- (IP) +
disp
(sign-extended
to 16-bits)
Description:
JCXZ short-label
JeXZ
(Jump if
ex
Zero) transfers control to
the target operand if
ex
is
O.
This instruction
is
useful at the beginning
of
a loop to bypass
the loop if
ex
has a zero value, i.e., to execute
the loop zero times.
Encoding:
1111
00011
disp
JCXZ
JCXZ Operands
Clocks Transfers
Bytes
JCXZ Coding Example
short-label
18
or 6
-
2
JCXZ COUNT
_DONE
2-91