Branch with Link to Register calls a subroutine at an address in a register, setting register X30 to PC+4.
| 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 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | Rn | 0 | 0 | 0 | 0 | 0 | ||||
| Z | op | A | M | Rm | |||||||||||||||||||||||||||
BLR <Xn>
integer n = UInt(Rn); BranchType branch_type; case op of when '00' branch_type = BranchType_INDIR; when '01' branch_type = BranchType_INDCALL; when '10' branch_type = BranchType_RET; otherwise UNDEFINED;
| <Xn> |
Is the 64-bit name of the general-purpose register holding the address to be branched to, encoded in the "Rn" field. |
Capability target; if CCTLR[].PCCBO == '1' then target = CapSetOffset(PCC[], X[n]); else target = CapSetValue(PCC[], X[n]); if branch_type == BranchType_INDCALL then if IsInC64() then if CCTLR[].SBL == '1' then C[30] = CapSetObjectType(CapAdd(PCC[], 5), CAP_SEAL_TYPE_RB); else C[30] = CapAdd(PCC[], 5); elsif CCTLR[].PCCBO == '1' then X[30] = PC[] + 4 - CapGetBase(PCC[]); else X[30] = PC[] + 4; BranchToCapability(target,branch_type);
Internal version only: isa v32.13, AdvSIMD v29.04, pseudocode morello-2022-01_rc2, capabilities morello-2022-01_rc2 ; Build timestamp: 2022-01-11T11:23
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