+ // LUi and ADDiu instructions create 32-bit offset of the target basic
+ // block from the target of BAL instruction. We cannot use immediate
+ // value for this offset because it cannot be determined accurately when
+ // the program has inline assembly statements. We therefore use the
+ // relocation expressions %hi($tgt-$baltgt) and %lo($tgt-$baltgt) which
+ // are resolved during the fixup, so the values will always be correct.
+ //
+ // Since we cannot create %hi($tgt-$baltgt) and %lo($tgt-$baltgt)
+ // expressions at this point (it is possible only at the MC layer),
+ // we replace LUi and ADDiu with pseudo instructions
+ // LONG_BRANCH_LUi and LONG_BRANCH_ADDiu, and add both basic
+ // blocks as operands to these instructions. When lowering these pseudo
+ // instructions to LUi and ADDiu in the MC layer, we will create
+ // %hi($tgt-$baltgt) and %lo($tgt-$baltgt) expressions and add them as
+ // operands to lowered instructions.
+
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::LONG_BRANCH_LUi), Mips::AT)
+ .addMBB(TgtMBB).addMBB(BalTgtMBB);