Intel Extensible Firmware Interface - Manual (Page 810)

Extensible Firmware Interface Specification
19-36 12/01/02 Version 1.10
Table 19-26. MOV Instruction Encoding
BYTE DESCRIPTION
Bit Description
7 0 = Operand 1 index absent
1 = Operand 1 index present
0
6 0 = Operand 2 index absent
1 = Operand 2 index present
0..5 0x1D = MOVbw opcode
0x1E = MOVww opcode
0x1F = MOVdw opcode
0x20 = MOVqw opcode
0x21 = MOVbd opcode
0x22 = MOVwd opcode
0x23 = MOVdd opcode
0x24 = MOVqd opcode
0x28 = MOVqq opcode
Bit Description
7 0 = Operand 2 direct
1 = Operand 2 indirect
4..6 Operand 2
3 0 = Operand 1 direct
1 = Operand 1 indirect
1
0..2 Operand 1
2..3 Optional Operand 1 16-bit index
2..3/4..5 Optional Operand 2 16-bit index
2..5 Optional Operand 1 32-bit index
2..5/6..9 Optional Operand 2 32-bit index
2..9 Optional Operand 1 64-bit index (MOVqq)
2..9/10..17 Optional Operand 2 64-bit index (MOVqq)
BEHAVIORS AND RESTRICTIONS:
• If an index is specified for Operand 1, and Operand 1 is direct, then an instruction encoding
exception is generated.