chkfeat

Check

CHK <#imm>

Check feature status (FEAT_CHK).

Pseudocode Operation

feature_id ← imm
if not CheckFeature(feature_id) then raise_exception(CHK_EXCEPTION)

Example

CHK #imm

Encoding

Binary Layout

11010101000000110010

31:12

0101

11:8

000

7:5

11111

4:0

 

Format System

Opcode 0xD503251F

Extension FEAT_CHK

Operands

• imm
  Feature ID

Related

More in FEAT_CHK

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0xD503251F	CHKFEAT X16		A64		11010101000000110010 | 0101 | 000 | 11111

Description

Check feature status. This instruction indicates the status of features. If FEAT_CHK is not implemented, this instruction executes as a NOP.

Operation

X[16, 64] = AArch64.ChkFeat(X[16, 64]);