Enum spirt::cfg::StructurizeRegionState

enum StructurizeRegionState {
    InProgress,
    Ready {
        backedge: Option<DeferredEdgeBundle<()>>,
        region: PartialControlRegion,
    },
    Claimed,
}

The state of one structurize_region_from invocation (keyed on its start ControlRegion in Structurizer) and its PartialControlRegion output.

There is a fourth (or 0th) implicit state, which is where nothing has yet observed some region, and Structurizer isn’t tracking it at all.

Variants

InProgress

Structurization is still running, and observing this is a cycle.

Ready

Fields

backedge: Option<DeferredEdgeBundle<()>>

If this region had backedges (targeting its start ControlRegion), their bundle is taken from the region’s DeferredEdgeBundleSet, and kept in this field instead (for simpler/faster access).

Claiming a region with backedges can combine them with the bundled edges coming into the CFG cycle from outside, and instead of failing due to the latter not being enough to claim the region on their own, actually perform loop structurization.

region: PartialControlRegion

Structurization completed, and this region can now be claimed.

Claimed

Region was claimed (by an IncomingEdgeBundle, with the appropriate total IncomingEdgeCount, minus any consumed_backedges), and has since likely been incorporated as part of some larger region.