ASR (immediate)

Arithmetic Shift Right (immediate) shifts a register value right by an immediate number of bits, shifting in copies of the sign bit in the upper bits and zeros in the lower bits, and writes the result to the destination register.

This is an alias of SBFM. This means:

313029282726252423222120191817161514131211109876543210
sf00100110Nimmrx11111RnRd
opcimms

32-bit (sf == 0 && N == 0 && imms == 011111)

ASR <Wd>, <Wn>, #<shift>

is equivalent to

SBFM <Wd>, <Wn>, #<shift>, #31

and is always the preferred disassembly.

64-bit (sf == 1 && N == 1 && imms == 111111)

ASR <Xd>, <Xn>, #<shift>

is equivalent to

SBFM <Xd>, <Xn>, #<shift>, #63

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 general-purpose source register, encoded in the "Rn" field.

<shift>

For the 32-bit variant: is the shift amount, in the range 0 to 31, encoded in the "immr" field.

For the 64-bit variant: is the shift amount, in the range 0 to 63, encoded in the "immr" 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 general-purpose source register, encoded in the "Rn" field.

Operation

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

Operational information

If PSTATE.DIT is 1:


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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