Assembler:Commands:OR

command or destination, source

The OR instruction is used for supporting logical expression by performing bitwise OR operation. The bitwise OR operator returns 1, if the matching bits from either or both operands are one. It returns 0, if both the bits are zero.

destination = destination | source

Example:

|             destination:     0101 |
|                  source:     0011 |
|-----------------------------------|
| After OR -> destination:     0111 |

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.

Performs a bitwise inclusive OR operation between 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 of the OR instruction is set to 0 if both corresponding bits of the first and second operands are 0; otherwise, each bit is set to 1.

c9x.me/x86/html/file_module_x86_id_219.html

Command Parameters

Parameter	Description
destination	The destination operand
source	The source operand

Examples

or al,1

or ax,1

or ax,1

or eax,1

or rax,1

or al,al

or ax,ax

or ax,ax

or eax,eax

or rax,rax

or [eax],eax

or [rax],rax

or [00123ABC],eax

or [SomeSymbol],rax

See also

• Assembler
• Auto Assembler
• Assembler Commands

External links

• wikipedia.org/wiki/X86_instruction_listings
• wikibooks.org/wiki/X86_Assembly/Other_Instructions
• c9x.me/x86/
• ref.x86asm.net
• https://www.felixcloutier.com/x86