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<TITLE>80386 Programmer's Reference Manual -- Appendix C</TITLE>
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<H1>Appendix C -- Status Flag Summary</H1>
<H3>Status Flags' Functions</H3>
<PRE>
Bit Name Function
0 CF Carry Flag -- Set on high-order bit carry or borrow; cleared
otherwise.
2 PF Parity Flag -- Set if low-order eight bits of result contain
an even number of 1 bits; cleared otherwise.
4 AF Adjust flag -- Set on carry from or borrow to the low order
four bits of AL; cleared otherwise. Used for decimal
arithmetic.
6 ZF Zero Flag -- Set if result is zero; cleared otherwise.
7 SF Sign Flag -- Set equal to high-order bit of result (0 is
positive, 1 if negative).
11 OF Overflow Flag -- Set if result is too large a positive number
or too small a negative number (excluding sign-bit) to fit in
destination operand; cleared otherwise.
</PRE>
<H3>Key to Codes</H3>
<PRE>
T = instruction tests flag
M = instruction modifies flag
(either sets or resets depending on operands)
0 = instruction resets flag
-- = instruction's effect on flag is undefined
blank = instruction does not affect flag
</PRE>
<PRE>
Instruction OF SF ZF AF PF CF
AAA -- -- -- TM -- M
AAS -- -- -- TM -- M
AAD -- M M -- M --
AAM -- M M -- M --
DAA -- M M TM M TM
DAS -- M M TM M TM
ADC M M M M M TM
ADD M M M M M M
SBB M M M M M TM
SUB M M M M M M
CMP M M M M M M
CMPS M M M M M M
SCAS M M M M M M
NEG M M M M M M
DEC M M M M M
INC M M M M M
IMUL M -- -- -- -- M
MUL M -- -- -- -- M
RCL/RCR 1 M TM
RCL/RCR count -- TM
ROL/ROR 1 M M
ROL/ROR count -- M
SAL/SAR/SHL/SHR 1 M M M -- M M
SAL/SAR/SHL/SHR count -- M M -- M M
SHLD/SHRD -- M M -- M M
BSF/BSR -- -- M -- -- --
BT/BTS/BTR/BTC -- -- -- -- -- M
AND 0 M M -- M 0
OR 0 M M -- M 0
TEST 0 M M -- M 0
XOR 0 M M -- M 0
</PRE>
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