Authenticate instruction address, using key A
This instruction authenticates an instruction address, using a modifier and key A.
If the authentication passes, the upper bits of the address are restored to enable subsequent use of the address. For information on behavior if the authentication fails, see Faulting on pointer authentication.
The address is:
The modifier is:
If FEAT_PAuth_LR is implemented and PSTATE.PACM is 1, then AUTIA1716 and AUTIASP include a second modifier that is:
It has encodings from 2 classes: Integer and System
| 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 | 0 | Z | 1 | 0 | 0 | Rn | Rd | ||||||||
| sf | S | opcode2 | |||||||||||||||||||||||||||||
AUTIZA <Xd>
if !IsFeatureImplemented(FEAT_PAuth) then EndOfDecode(Decode_UNDEF); if Z == '1' && Rn != '11111' then EndOfDecode(Decode_UNDEF); constant boolean autia1716 = FALSE; constant integer d = UInt(Rd); constant integer n = UInt(Rn); constant boolean auth_combined = FALSE; constant boolean source_is_sp = Z == '0' && n == 31;
| 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 | x | 1 | 1 | 0 | x | 1 | 1 | 1 | 1 | 1 |
| CRm | op2 | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_PAuth) then EndOfDecode(Decode_NOP); integer d; integer n; boolean source_is_sp = FALSE; boolean autia1716 = FALSE; constant boolean auth_combined = FALSE; case CRm:op2 of when '0011 100' // AUTIAZ d = 30; n = 31; when '0011 101' // AUTIASP d = 30; source_is_sp = TRUE; when '0001 100' // AUTIA1716 d = 17; n = 16; autia1716 = TRUE;
| <Xd> |
Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field. |
| <Xn|SP> |
Is the 64-bit name of the general-purpose source register or stack pointer, encoded in the "Rn" field. |
if source_is_sp then if IsFeatureImplemented(FEAT_PAuth_LR) && PSTATE.PACM == '1' then X[d, 64] = AuthIA2(X[d, 64], SP[64], X[16, 64], auth_combined); else X[d, 64] = AuthIA(X[d, 64], SP[64], auth_combined); else if IsFeatureImplemented(FEAT_PAuth_LR) && PSTATE.PACM == '1' && autia1716 then X[d, 64] = AuthIA2(X[d, 64], X[n, 64], X[15, 64], auth_combined); else X[d, 64] = AuthIA(X[d, 64], X[n, 64], auth_combined);
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