Difference between revisions of "Assembler:Commands:NEG"
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The Neg instruction performs a Two's Complement Negation. Negating positive operand becomes negative. Negating negative operand becomes positive. Zero remains zero. | The Neg instruction performs a Two's Complement Negation. Negating positive operand becomes negative. Negating negative operand becomes positive. Zero remains zero. | ||
The two's complement of a number behaves like the negative of the original number. | The two's complement of a number behaves like the negative of the original number. | ||
+ | |||
+ | The '''CF''' flag set to 0 if the source operand is 0; otherwise it is set to 1. The '''OF''', '''SF''', '''ZF''', '''AF''', and '''PF''' flags are set according to the result. | ||
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Replaces the value of operand (the destination operand) with its two's complement. (This operation is equivalent to subtracting the operand from 0.) The destination operand is located in a general-purpose register or a memory location. | Replaces the value of operand (the destination operand) with its two's complement. (This operation is equivalent to subtracting the operand from 0.) The destination operand is located in a general-purpose register or a memory location. | ||
− | [ | + | [https://c9x.me/x86/html/file_module_x86_id_216.html c9x.me/x86/html/file_module_x86_id_216.html] |
</div> | </div> | ||
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== External links == | == External links == | ||
− | * [ | + | * [https://c9x.me/x86/ c9x.me/x86/] |
* [http://ref.x86asm.net/ ref.x86asm.net] | * [http://ref.x86asm.net/ ref.x86asm.net] | ||
* [https://wikipedia.org/wiki/X86_instruction_listings wikipedia.org/wiki/X86_instruction_listings] | * [https://wikipedia.org/wiki/X86_instruction_listings wikipedia.org/wiki/X86_instruction_listings] |
Latest revision as of 02:53, 5 January 2018
command neg operand
The Neg instruction performs a Two's Complement Negation. Negating positive operand becomes negative. Negating negative operand becomes positive. Zero remains zero. The two's complement of a number behaves like the negative of the original number.
The CF flag set to 0 if the source operand is 0; otherwise it is set to 1. The OF, SF, ZF, AF, and PF flags are set according to the result.
Operand = -Operand
Replaces the value of operand (the destination operand) with its two's complement. (This operation is equivalent to subtracting the operand from 0.) The destination operand is located in a general-purpose register or a memory location.
Command Parameters[edit]
Parameter | Description |
---|---|
operand | The operand to perform a Negate operation on |
Examples[edit]
neg al
neg ah
neg ax
neg eax
neg rax
neg [edx+110]
neg [rdx+10]
neg [00123abc]
neg [UserDefinedSymbol]
See also[edit]