此言差已!
TEST―Logical Compare
Description
Computes the bit-wise logical AND of first operand (source 1 operand) and the second operand
(source 2 operand) and sets the SF, ZF, and PF status flags according to the result. The result is
then discarded.
Operation
TEMP ¬ SRC1 AND SRC2;
SF ¬ MSB(TEMP);
IF TEMP = 0
THEN ZF ¬ 0;
ELSE ZF ¬ 1;
FI:
PF ¬ BitwiseXNOR(TEMP[0:7]);
CF ¬ 0;
OF ¬ 0;
(*AF is Undefined*)
Flags Affected
The OF and CF flags are cleared to 0. The SF, ZF, and PF flags are set according to the result
(see the “Operation” section above). The state of the AF flag is undefined.
Opcode Instruction Description
A8 ib TEST AL, imm8 AND imm8 with AL; set SF, ZF, PF according to result
A9 iw TEST AX, imm16 AND imm16 with AX; set SF, ZF, PF according to result
A9 id TEST EAX, imm32 AND imm32 with EAX; set SF, ZF, PF according to result
F6 /0 ib TEST r/m8,imm8 AND imm8 with r/m8; set SF, ZF, PF according to result
F7 /0 iw TEST r/m16,imm16 AND imm16 with r/m16; set SF, ZF, PF according to result
F7 /0 id TEST r/m32,imm32 AND imm32 with r/m32; set SF, ZF, PF according to result
84 / r TEST r/m8,r8 AND r8 with r/m8; set SF, ZF, PF according to result
85 / r TEST r/m16,r16 AND r16 with r/m16; set SF, ZF, PF according to result
85 / r TEST r/m32,r32 AND r32 with r/m32; set SF, ZF, PF according to result
