16.28 BFC

Bitfield Clear, leaving other bits unchanged.

This instruction is an alias of BFM.

The equivalent instruction is BFM Wd, WZR, #(-lsb MOD 32), #(width-1).

Syntax

BFC Wd, #lsb, #width ; 32-bit

BFC Xd, #lsb, #width ; 64-bit

Where:

Wd
Is the 32-bit name of the general-purpose destination register.
lsb

Depends on the instruction variant:

32-bit general registers
Is the bit number of the lsb of the destination bitfield, in the range 0 to 31.
64-bit general registers
Is the bit number of the lsb of the destination bitfield, in the range 0 to 63.
width

Depends on the instruction variant:

32-bit general registers
Is the width of the bitfield, in the range 1 to 32-lsb.
64-bit general registers
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.

Architectures supported

Supported in the Arm®v8.2 architecture and later.

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