3.2.6 Bit and Byte Instructions
The bit instructions test and modify individual bits in operands.
The byte instructions set the value of a byte operand to indicate the status
of flags in the %eflags register.
Table 3-7 Bit and Byte Instructions
| | | |
|---|
|
| BSF
| bit scan forward
| bsfq valid only under –m64
|
|
| BSR
| bit scan reverse
| bsrq valid only under –m64
|
|
| BT
| bit test
| btq valid only under –m64
|
|
| BTC
| bit test and complement
| btcq valid only under –m64
|
|
| BTR
| bit test and reset
| btrq valid only under –m64
|
|
| BTS
| bit test and set
| btsq valid only under –m64
|
|
| SETA
| set byte if above
|
|
|
| SETAE
| set byte if above or equal
|
|
|
| SETB
| set byte if below
|
|
|
| SETBE
| set byte if below or equal
|
|
|
| SETC
| set byte if carry
|
|
|
| SETE
| set byte if equal
|
|
|
| SETG
| set byte if greater
|
|
|
| SETGE
| set byte if greater or equal
|
|
|
| SETL
| set byte if less
|
|
|
| SETLE
| set byte if less or equal
|
|
|
| SETNA
| set byte if not above
|
|
|
| SETNAE
| set byte if not above or equal
|
|
|
| SETNB
| set byte if not below
|
|
|
| SETNBE
| set byte if not below or equal
|
|
|
| SETNC
| set byte if not carry
|
|
|
| SETNE
| set byte if not equal
|
|
|
| SETNG
| set byte if not greater
|
|
|
| SETNGE
| set byte if not greater or equal
|
|
|
| SETNL
| set byte if not less
|
|
|
| SETNLE
| set byte if not less or equal
|
|
|
| SETNO
| set byte if not overflow
|
|
|
| SETNP
| set byte if not parity
|
|
|
| SETNS
| set byte if not sign (non-negative)
|
|
|
| SETNZ
| set byte if not zero
|
|
|
| SETO
| set byte if overflow
|
|
|
| SETP
| set byte if parity
|
|
|
| SETPE
| set byte if parity even
|
|
|
| SETPO
| set byte if parity odd
|
|
|
| SETS
| set byte if sign (negative)
|
|
|
| SETZ
| set byte if zero
|
|
test{bwlq}
|
| logical compare
| testq valid only under –m64
|
|