Branch with Link branches to a PC-relative offset, setting the register X30 to PC+4. It provides a hint that this is a subroutine call.
| 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 | 0 | 0 | 1 | 0 | 1 | imm26 | |||||||||||||||||||||||||
| op | |||||||||||||||||||||||||||||||
BL <label>
BranchType branch_type = if op == '1' then BranchType_DIRCALL else BranchType_DIR; bits(64) offset = SignExtend(imm26:'00', 64);
| <label> |
Is the program label to be unconditionally branched to. Its offset from the address of this instruction, in the range +/-128MB, is encoded as "imm26" times 4. |
if branch_type == BranchType_DIRCALL then X[30] = PC[] + 4; boolean branch_conditional = FALSE; BranchTo(PC[] + offset, branch_type, branch_conditional);
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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