RET -- A64

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RET -- A64

RET

Return from subroutine

This instruction branches unconditionally to an address in a register. This instruction provides a hint that this is a subroutine return.

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	1	0	0	1	0	1	1	1	1	1	0	0	0	0	0	0	Rn					0	0	0	0	0
							Z		op		op2									A	M						Rm

Encoding

Decode for this encoding

let n : integer{} = UInt(Rn);

Assembler Symbols

<Xn>	Is the 64-bit name of the general-purpose register holding the address to be branched to, encoded in the "Rn" field. Defaults to X30 if absent.

Operation

var target : bits(64) = X{}(n); if IsFeatureImplemented(FEAT_GCS) && GCSPCREnabled(PSTATE.EL) then target = LoadCheckGCSRecord(target, GCSInstType_PRET); SetCurrentGCSPointer(GetCurrentGCSPointer() + 8); end; // Value in BTypeNext will be used to set PSTATE.BTYPE BTypeNext = '00'; let branch_conditional : boolean = FALSE; BranchTo{64}(target, BranchType_RET, branch_conditional);

2026-03_rel 2026-03-26 20:48:11

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