BLR

Branch with link to register

This instruction calls a subroutine at an address in a register, setting register X30 to PC+4. This instruction provides a hint that this is a subroutine call.

313029282726252423222120191817161514131211109876543210
1101011000111111000000Rn00000
Zopop2AMRm

Encoding

BLR <Xn>

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.

Operation

let target : bits(64) = X{}(n); if IsFeatureImplemented(FEAT_GCS) && GCSPCREnabled(PSTATE.EL) then AddGCSRecord(PC64() + 4); end; // Value in BTypeNext will be used to set PSTATE.BTYPE BTypeNext = '10'; X{64}(30) = PC64() + 4; let branch_conditional : boolean = FALSE; BranchTo{64}(target, BranchType_INDCALL, branch_conditional);


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

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