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ASR (register)

Arithmetic shift right (register)

This instruction shifts a register value right by a variable number of bits, shifting in copies of its sign bit, and writes the result to the destination register. The value of the second source register modulo the register size in bits gives the number of bits by which the first source register is right-shifted.

This is an alias of ASRV. This means:

313029282726252423222120191817161514131211109876543210
sf0011010110Rm001010RnRd
Sop2

32-bit encoding

(sf == 0)

ASR <Wd>, <Wn>, <Wm>

is equivalent to

ASRV <Wd>, <Wn>, <Wm>

and is always the preferred disassembly.

64-bit encoding

(sf == 1)

ASR <Xd>, <Xn>, <Xm>

is equivalent to

ASRV <Xd>, <Xn>, <Xm>

and is always the preferred disassembly.

Assembler Symbols

<Wd>

Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Wn>

Is the 32-bit name of the first general-purpose source register, encoded in the "Rn" field.

<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, encoded in the "Rm" field.

<Xd>

Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Xn>

Is the 64-bit name of the first general-purpose source register, encoded in the "Rn" field.

<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, encoded in the "Rm" field.

Operation

The description of ASRV gives the operational pseudocode for this instruction.

Operational Information

The description of ASRV gives the operational information for this instruction.

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