16.85 LSL (register)

Logical Shift Left (register).

This instruction is an alias of LSLV.

The equivalent instruction is LSLV Wd, Wn, Wm.

Syntax

LSL Wd, Wn, Wm ; 32-bit

LSL Xd, Xn, Xm ; 64-bit

Where:

Wd
Is the 32-bit name of the general-purpose destination register.
Wn
Is the 32-bit name of the first general-purpose source register.
Wm
Is the 32-bit name of the second general-purpose source register holding a shift amount from 0 to 31 in its bottom 5 bits.
Xd
Is the 64-bit name of the general-purpose destination register.
Xn
Is the 64-bit name of the first general-purpose source register.
Xm
Is the 64-bit name of the second general-purpose source register holding a shift amount from 0 to 63 in its bottom 6 bits.

Operation

Logical Shift Left (register) shifts a register value left by a variable number of bits, shifting in zeros, and writes the result to the destination register. The remainder obtained by dividing the second source register by the data size defines the number of bits by which the first source register is left-shifted.

Rd = LSL(Rn, Rm), where R is either W or X.

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