B2.63 ID_AA64ISAR1_EL1, AArch64 Instruction Set Attribute Register 1, EL1

The ID_AA64ISAR1_EL1 provides information about the instructions implemented in AArch64 state.

Bit field descriptions

ID_AA64ISAR1_EL1 is a 64-bit register, and is part of the Identification registers functional group.

This register is Read Only.

Figure B2-46 ID_AA64ISAR1_EL1 bit assignments
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RES0, [63:24]
LRCPC, [23:20]

Indicates whether load-acquire (LDA) instructions are implemented for a Release Consistent core consistent RCPC model.


The LDAPRB, LDAPRH, and LDAPR instructions are implemented in AArch64.

RES0, [19:4]
DC CVAP, [3:0]

Indicates whether Data Cache, Clean to the Point of Persistence (DC CVAP) instructions are implemented.


DC CVAP is supported in AArch64.


There are no configuration notes.

Bit fields and details that are not provided in this description are architecturally defined. See the Arm® Architecture Reference Manual Armv8, for Armv8-A architecture profile.

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