Intel 210200-002 manual SAL Shift Arithmetic Left SHL Shift Logical Left, Cf, Of, Pf, Sf, Zf

SAL SHIFT ARITHMETIC LEFT SHL SHIFT LOGICAL LEFT

Operation:	Flags Affected:
(temp) +-- COUNT	CF, OF, PF, SF, ZF.
do while (temp) =1= 0	AF undefined
(CF) +-- high-order bit of (EA)
(EA) +-- (EA) * 2
(temp) +-- (temp)-1
if COUNT = 1 then
if high-order bit of (EA) =1= (CE)
then (OF) +--1
else (OF) +--0
else (OF) undefined
Description:
SHL/SAL destination, count

SHL and SAL (Shift Logical Left and Shift Arithmetic Left) perform the same operation and are physically the same instruction. The destination byte or word is shifted left by the number of bits specified in the count operand. Zeros are shifted in on the right. If the sign bit retains its original value, then OF is cleared.

SAL SHL

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