B-10
INSTRUCTION FORMATS AND ENCODINGS
INT n Interrupt Type n
1100 1101 : type
INT Single-Step Interrupt 3
1100 1100
INTO Interrupt 4 on Overflow
1100 1110
INVD Invalidate Cache
0000 1111 : 0000 1000
INVLPG Invalidate TLB Entry
0000 1111 : 0000 0001 : mod 111 r/m
IRET/IRETD Interrupt Return
1100 1111
Jcc Jump if Condition is Met
8-bit displacement
0111 tttn : 8-bit displacement
full displacement
0000 1111 : 1000 tttn : full displacement
JCXZ/JECXZ Jump on CX/ECX Zero
Address-size prefix differentiates JCXZ
and JECXZ
1110 0011 : 8-bit displacement
JMP Unconditional Jump (to same segment)
short
1110 1011 : 8-bit displacement
direct
1110 1001 : full displacement
register indirect
1111 1111 : 11 100 reg
memory indirect
1111 1111 : mod 100 r/m
JMP Unconditional Jump (to other segment)
direct intersegment
1110 1010 : unsigned full offset, selector
indirect intersegment
1111 1111 : mod 101 r/m
LAHF Load Flags into AHRegister
1001 1111
LAR Load Access Rights Byte
from register
0000 1111 : 0000 0010 : 11 reg1 reg2
from memory
0000 1111 : 0000 0010 : mod reg r/m
LDS Load Pointer to DS
1100 0101 : mod reg r/m
LEA Load Effective Address
1000 1101 : mod reg r/m
LEAVE High Level Procedure Exit
1100 1001
LES Load Pointer to ES
1100 0100 : mod reg r/m
LFS Load Pointer to FS
0000 1111 : 1011 0100 : mod reg r/m
LGDT Load Global Descriptor Table Register0000 1111 : 0000 0001 : mod 010 r/m
LGS Load Pointer to GS
0000 1111 : 1011 0101 : mod reg r/m
LIDT Load Interrupt Descriptor Table Register
LLDT Load Local Descriptor Table Register
LDTR from register
0000 1111 : 0000 0000 : 11 010 reg
LDTR from memory
0000 1111 : 0000 0000 : mod 010 r/m
Table B-10. Integer Instruction Formats and Encodings (Contd.)
Instruction and Format
Encoding
