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BFXIL

Bitfield extract and insert at low end

This instruction copies a bitfield of <width> bits starting from bit position <lsb> in the source register to the least significant bits of the destination register, leaving the other destination bits unchanged.

This is an alias of BFM. This means:

313029282726252423222120191817161514131211109876543210
sf01100110NimmrimmsRnRd
opc

32-bit encoding

(sf == 0 && N == 0)

BFXIL <Wd>, <Wn>, #<lsb>, #<width>

is equivalent to

BFM <Wd>, <Wn>, #<lsb>, #(<lsb>+<width>-1)

and is the preferred disassembly when UInt(imms) >= UInt(immr).

64-bit encoding

(sf == 1 && N == 1)

BFXIL <Xd>, <Xn>, #<lsb>, #<width>

is equivalent to

BFM <Xd>, <Xn>, #<lsb>, #(<lsb>+<width>-1)

and is the preferred disassembly when UInt(imms) >= UInt(immr).

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.

<lsb>

For the "32-bit" variant: is the bit number of the lsb of the source bitfield, in the range 0 to 31.

For the "64-bit" variant: is the bit number of the lsb of the source bitfield, in the range 0 to 63.

<width>

For the "32-bit" variant: is the width of the bitfield, in the range 1 to 32-<lsb>.

For the "64-bit" variant: is the width of the bitfield, in the range 1 to 64-<lsb>.

<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 BFM gives the operational pseudocode for this instruction.

Operational Information

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


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