Difference between revisions of "X86 microop ISA"
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== Sub == | == Sub == | ||
+ | |||
+ | === sub: Dest = Src1 - Src2 === | ||
+ | Subtracts the contents of the Src2 register from the Src1 register and puts the result in the Dest register. | ||
+ | |||
+ | === subi: Dest = Src1 + Imm === | ||
+ | Subtracts the contents of the Src1 register and the immediate Imm and puts the result in the Dest register. | ||
+ | |||
+ | === Flags === | ||
+ | This microop optionally sets the CF, ECF, ZF, EZF, PF, AF, SF, and OF flags. | ||
+ | |||
+ | <table> | ||
+ | <tr> | ||
+ | <td> <b>CF and ECF</b> </td><td>The barrow into of the most significant bit.</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td> <b>ZF and EZF</b> </td><td>Whether the result was zero.</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td> <b>PF</b> </td><td> The parity of the result. </td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td> <b>AF</b> </td><td> The barrow from the 5th to 4th bit positions. </td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td> <b>SF</b> </td><td> The sign of the result. </td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td> <b>OF</b> </td><td> Whether there was an overflow. </td> | ||
+ | </tr> | ||
+ | </table> | ||
== Sbb == | == Sbb == |
Revision as of 15:00, 27 September 2007
Contents
- 1 Register Ops
- 2 Load/Store Ops
- 3 Load immediate Op
Register Ops
Add
add: Dest = Src1 + Src2
Adds the contents of the Src1 and Src2 registers and puts the result in the Dest register.
addi: Dest = Src1 + Imm
Adds the contents of the Src1 register and the immediate Imm and puts the result in the Dest register.
Flags
This microop optionally sets the CF, ECF, ZF, EZF, PF, AF, SF, and OF flags.
CF and ECF | The carry out of the most significant bit. |
ZF and EZF | Whether the result was zero. |
PF | The parity of the result. |
AF | The carry from the 4th to 5th bit positions. |
SF | The sign of the result. |
OF | Whether there was an overflow. |
Adc
adc: Dest = Src1 + Src2 + CF
Adds the contents of the Src1 and Src2 registers and the carry flag and puts the result in the Dest register.
adci: Dest = Src1 + Imm + CF
Adds the contents of the Src1 register, the immediate Imm, and the carry flag and puts the result in the Dest register.
Flags
This microop optionally sets the CF, ECF, ZF, EZF, PF, AF, SF, and OF flags.
CF and ECF | The carry out of the most significant bit. |
ZF and EZF | Whether the result was zero. |
PF | The parity of the result. |
AF | The carry from the 4th to 5th bit positions. |
SF | The sign of the result. |
OF | Whether there was an overflow. |
Sub
sub: Dest = Src1 - Src2
Subtracts the contents of the Src2 register from the Src1 register and puts the result in the Dest register.
subi: Dest = Src1 + Imm
Subtracts the contents of the Src1 register and the immediate Imm and puts the result in the Dest register.
Flags
This microop optionally sets the CF, ECF, ZF, EZF, PF, AF, SF, and OF flags.
CF and ECF | The barrow into of the most significant bit. |
ZF and EZF | Whether the result was zero. |
PF | The parity of the result. |
AF | The barrow from the 5th to 4th bit positions. |
SF | The sign of the result. |
OF | Whether there was an overflow. |