3-446
INSTRUCTION SET REFERENCE
MOVZXMove with Zero-Extend
Description
This instruction copies the contents of the source operand (register or memory location) to the
destination operand (register) and zero extends the value to 16 or 32 bits. The size of the
converted value depends on the operand-size attribute.
Operation
DEST
<
ZeroExtend(SRC);
Flags Affected
None.
Protected Mode Exceptions
#GP(0)
If a memory operand effective address is outside the CS, DS, ES, FS, or
GS segment limit.
If the DS, ES, FS, or GS register contains a null segment selector.
#SS(0)
If a memory operand effective address is outside the SS segment limit.
#PF(fault-code)If a page fault occurs.
#AC(0)
If alignment checking is enabled and an unaligned memory reference is
made while the current privilege level is 3.
Real-Address Mode Exceptions
#GP
If a memory operand effective address is outside the CS, DS, ES, FS, or
GS segment limit.
#SS
If a memory operand effective address is outside the SS segment limit.
Opcode
Instruction
Description
0F B6 /r
MOVZX r16,r/m8
Move byte to word with zero-extension
0F B6 /r
MOVZX r32,r/m8
Move byte to doubleword, zero-extension
0F B7 /r
MOVZX r32,r/m16
Move word to doubleword, zero-extension
