53 lines
5.0 KiB
Markdown
Executable File
53 lines
5.0 KiB
Markdown
Executable File
# ADC — Add with Carry
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## Description
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Adds the destination operand (first operand), the source operand (second operand), and the carry (CF) flag and stores the result in the
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destination operand. The destination operand can be a register or a memory location; the source operand can be an immediate, a register, or a
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memory location. However, two memory operands cannot be used in one instruction. The state of the CF flag represents a carry from a previous
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addition. When an immediate value is used as an operand, it is sign-extended to the length of the destination operand format.
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## Instruction
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| Opcode | Assembly | Op/En | Modern Mode | Legacy Mode | Description |
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|------------------|------------------|-------|-------------|-------------|--------------------------------------------------------------------|
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| 14 ib | ADC AL, imm8 | I | Valid | Valid | Add with carry imm8 to AL. |
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| 15 iw | ADC AX, imm16 | I | Valid | Valid | Add with carry imm16 to AX. |
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| 15 id | ADC EAX, imm32 | I | Valid | Valid | Add with carry imm32 to EAX. |
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| REX.W + 15 id | ADC RAX, imm32 | I | Valid | N.E. | Add with carry imm32 sign extended to 64-bits to RAX. |
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| 80 /2 ib | ADC r/m8, imm8 | MI | Valid | Valid | Add with carry imm8 to r/m8. |
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| REX + 80 /2 ib | ADC r/m8*, imm8 | MI | Valid | N.E. | Add with carry imm8 to r/m8. |
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| 81 /2 iw | ADC r/m16, imm16 | MI | Valid | Valid | Add with carry imm16 to r/m16. |
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| 81 /2 id | ADC r/m32, imm32 | MI | Valid | Valid | Add with CF imm32 to r/m32. |
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| REX.W + 81 /2 id | ADC r/m64, imm32 | MI | Valid | N.E. | Add with CF imm32 sign extended to 64-bits to r/m64. |
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| 83 /2 ib | ADC r/m16, imm8 | MI | Valid | Valid | Add with CF sign-extended imm8 to r/m16. |
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| 83 /2 ib | ADC r/m32, imm8 | MI | Valid | Valid | Add with CF sign-extended imm8 into r/m32. |
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| REX.W + 83 /2 ib | ADC r/m64, imm8 | MI | Valid | N.E. | Add with CF sign-extended imm8 into r/m64. |
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| 10 /r | ADC r/m8, r8 | MR | Valid | Valid | Add with carry byte register to r/m8. |
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| REX + 10 /r | ADC r/m8*, r8* | MR | Valid | N.E. | Add with carry byte register to r/m64. |
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| 11 /r | ADC r/m16, r16 | MR | Valid | Valid | Add with carry r16 to r/m16. |
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| 11 /r | ADC r/m32, r32 | MR | Valid | Valid | Add with CF r32 to r/m32. |
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| REX.W + 11 /r | ADC r/m64, r64 | MR | Valid | N.E. | Add with CF r64 to r/m64. |
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| 12 /r | ADC r8, r/m8 | RM | Valid | Valid | Add with carry r/m8 to byte register. |
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| REX + 12 /r | ADC r8*, r/m8* | RM | Valid | N.E. | Add with carry r/m64 to byte register. |
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| 13 /r | ADC r16, r/m16 | RM | Valid | Valid | Add with carry r/m16 to r16. |
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| 13 /r | ADC r32, r/m32 | RM | Valid | Valid | Add with CF r/m32 to r32. |
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| REX.W + 13 /r | ADC r64, r/m64 | RM | Valid | N.E. | Add with CF r/m64 to r64. |
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- 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.
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## Information
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This instruction can be used with a LOCK prefix to allow the instruction to be executed atomically.
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The ADC instruction does not distinguish between signed or unsigned operands. Instead, the processor evaluates the result for both data types
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and sets the OF and CF flags to indicate a carry in the signed or unsigned result, respectively. The SF flag indicates the sign of the signed
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result.
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The ADC instruction is usually executed as part of a multibyte or multiword addition in which an ADD instruction is followed by an ADC
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instruction.
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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
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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
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section for encoding data and limits.
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