XPACD, XPACI, XPACLRI

Strip Pointer Authentication Code

This instruction removes the Pointer Authentication Code from an address. The address is in the specified general-purpose register for XPACI and XPACD, and is in LR for XPACLRI.

The XPACD instruction is used for data addresses, and XPACI and XPACLRI are used for instruction addresses.

It has encodings from 2 classes: Integer and System

Integer class

(FEAT_PAuth)

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
1	1	0	1	1	0	1	0	1	1	0	0	0	0	0	1	0	1	0	0	0	D	1	1	1	1	1	Rd
sf		S									opcode2											Rn

XPACD encoding

(D == 1)

XPACD <Xd>

XPACI encoding

(D == 0)

XPACI <Xd>

Decode (all encodings)

if !IsFeatureImplemented(FEAT_PAuth) then EndOfDecode(Decode_UNDEF); constant integer d = UInt(Rd); constant boolean data = (D == '1');

System class

(FEAT_PAuth)

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
1	1	0	1	0	1	0	1	0	0	0	0	0	0	1	1	0	0	1	0	0	0	0	0	1	1	1	1	1	1	1	1
																				CRm				op2

Encoding

XPACLRI

Decode

if !IsFeatureImplemented(FEAT_PAuth) then EndOfDecode(Decode_NOP); constant integer d = 30; constant boolean data = FALSE;

Assembler Symbols

<Xd>	Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

Operation

X[d, 64] = Strip(X[d, 64], data);

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31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
1	1	0	1	0	1	0	1	0	0	0	0	0	0	1	1	0	0	1	0	0	0	0	0	1	1	1	1	1	1	1	1
																				CRm				op2

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
1	1	0	1	0	1	0	1	0	0	0	0	0	0	1	1	0	0	1	0	0	0	0	0	1	1	1	1	1	1	1	1
																				CRm				op2