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Henk-Jan Lebbink edited this page Jun 5, 2018 · 12 revisions

AND — Logical AND

Opcode Instruction Op/ En 64-bit Mode Compat/ Leg Mode Description
24 ib AND AL, imm8 I Valid Valid AL AND imm8.
25 iw AND AX, imm16 I Valid Valid AX AND imm16.
25 id AND EAX, imm32 I Valid Valid EAX AND imm32.
REX.W + 25 id AND RAX, imm32 I Valid N.E. RAX AND imm32 sign-extended to 64-bits.
80 /4 ib AND r/m8, imm8 MI Valid Valid r/m8 AND imm8.
REX + 80 /4 ib AND r/m8*, imm8 MI Valid N.E. r/m8 AND imm8.
81 /4 iw AND r/m16, imm16 MI Valid Valid r/m16 AND imm16.
81 /4 id AND r/m32, imm32 MI Valid Valid r/m32 AND imm32.
REX.W + 81 /4 id AND r/m64, imm32 MI Valid N.E. r/m64 AND imm32 sign extended to 64-bits.
83 /4 ib AND r/m16, imm8 MI Valid Valid r/m16 AND imm8 (sign-extended).
83 /4 ib AND r/m32, imm8 MI Valid Valid r/m32 AND imm8 (sign-extended).
REX.W + 83 /4 ib AND r/m64, imm8 MI Valid N.E. r/m64 AND imm8 (sign-extended).
20 /r AND r/m8, r8 MR Valid Valid r/m8 AND r8.
REX + 20 /r AND r/m8*, r8* MR Valid N.E. r/m64 AND r8 (sign-extended).
21 /r AND r/m16, r16 MR Valid Valid r/m16 AND r16.
21 /r AND r/m32, r32 MR Valid Valid r/m32 AND r32.
REX.W + 21 /r AND r/m64, r64 MR Valid N.E. r/m64 AND r32.
22 /r AND r8, r/m8 RM Valid Valid r8 AND r/m8.
REX + 22 /r AND r8*, r/m8* RM Valid N.E. r/m64 AND r8 (sign-extended).
23 /r AND r16, r/m16 RM Valid Valid r16 AND r/m16.
23 /r AND r32, r/m32 RM Valid Valid r32 AND r/m32.
REX.W + 23 /r AND r64, r/m64 RM Valid N.E. r64 AND r/m64.

*In 64-bit mode, r/m8 can not be encoded to access the following byte registers if a REX prefix is used: AH, BH, CH, DH.

Instruction Operand Encoding

Op/En Operand 1 Operand 2 Operand 3 Operand 4
RM ModRM:reg (r, w) ModRM:r/m (r) NA NA
MR ModRM:r/m (r, w) ModRM:reg (r) NA NA
MI ModRM:r/m (r, w) imm8/16/32 NA NA
I AL/AX/EAX/RAX imm8/16/32 NA NA

Description

Performs a bitwise AND operation on the destination (first) and source (second) operands and stores the result in the destination operand location. The source operand can be an immediate, a register, or a memory location; the destination operand can be a register or a memory location. (However, two memory operands cannot be used in one instruction.) Each bit of the result is set to 1 if both corresponding bits of the first and second operands are 1; otherwise, it is set to 0.

This instruction can be used with a LOCK prefix to allow the it to be executed atomically.

In 64-bit mode, the instruction’s default operation size is 32 bits. Using a REX prefix in the form of REX.R permits access to additional registers (R8-R15). Using a REX prefix in the form of REX.W promotes operation to 64 bits. See the summary chart at the beginning of this section for encoding data and limits.

Operation

DESTDEST AND SRC;

Flags Affected

The OF and CF flags are cleared; the SF, ZF, and PF flags are set according to the result. The state of the AF flag is undefined.

Protected Mode Exceptions

#GP(0) If the destination operand points to a non-writable segment. 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.

#UD If the LOCK prefix is used but the destination is not a memory operand.

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.

#UD If the LOCK prefix is used but the destination is not a memory operand.

Virtual-8086 Mode Exceptions

#GP(0) If a memory operand effective address is outside the CS, DS, ES, FS, or GS segment limit.

#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.

#UD If the LOCK prefix is used but the destination is not a memory operand.

Compatibility Mode Exceptions

Same exceptions as in protected mode.

64-Bit Mode Exceptions

#SS(0) If a memory address referencing the SS segment is in a non-canonical form.

#GP(0) If the memory address is in a non-canonical form.

#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.

#UD If the LOCK prefix is used but the destination is not a memory operand.


Source: Intel® Architecture Software Developer's Manual (May 2018)
Generated: 5-6-2018

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