Pointer Authentication Code for Data address, using key A. This instruction computes and inserts a pointer authentication code for a data address, using a modifier and key A.

The address is in the general-purpose register that is specified by <Xd>.

The modifier is:



PACDA (Z == 0)

PACDA <Xd>, <Xn|SP>

PACDZA (Z == 1 && Rn == 11111)


boolean source_is_sp = FALSE; integer d = UInt(Rd); integer n = UInt(Rn); if !HavePACExt() then UNDEFINED; if Z == '0' then // PACDA if n == 31 then source_is_sp = TRUE; else // PACDZA if n != 31 then UNDEFINED;

Assembler Symbols


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


Is the 64-bit name of the general-purpose source register or stack pointer, encoded in the "Rn" field.


if source_is_sp then X[d] = AddPACDA(X[d], SP[]); else X[d] = AddPACDA(X[d], X[n]);

Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41

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