An instruction for inserting a write barrier. This instruction is almost always inserted after a
instruction. If the container object is in an older generation than the item inserted, this instruction guarantees that the item will not be garbage collected. It has the following slots:
src | Object to which the writer barrier refers. |
slot | Slot index of the object. |
scale | No idea. |
tag | Type tag for obj. |
temp1 | First temporary register to clobber. |
temp2 | Second temporary register to clobber. |