n [ForceInline] functions in bounded-depth groups. The inliner collapses each group into its group-top; the entry sums all group-tops, giving the SSA simplifier large bodies to chew on. Scales by breadth (bounded nesting). Scaling null: n scales call sites with bounded inlining depth; ideal cost is O(n).
bucket: inlining · mode: target · flags: -target spirv -emit-spirv-directly
compileInner split into phase buckets (named leaves + (self) residuals) stacked across the sweep sizes — the top edge is compileInner, so you can see which phase drives the scaling.
floor-subtracted power-law fit (t − floor) = a·Nk; floor = the minimal workload (fixed per-compile cost), k the global exponent, top-2× the local high-end doubling ratio.
| N range | floor (ms) | k (work) | fit R² | t(Nmin) | t(Nmax) | top-2× |
|---|---|---|---|---|---|---|
| 100–800 | 9 | 0.82 | 0.992 | 43 | 197 | 1.86× |
compileInner grows by 154 ms across the sweep; the mutually-exclusive phase buckets below partition that growth exactly (no nested-timer double counting). × lin is the same metric as the top-level panels, per bucket: the end point vs a linear expectation anchored to the bucket's share of the minimal floor and fitted on the low-N half — 1.0 = grew exactly linearly, >1 bends up. The super-linearity lives where × lin (and k) are red.
| bucket | t@N=100 | t@N=800 | Δ ms | share | × lin | ∝Nk |
|---|---|---|---|---|---|---|
| SemanticChecking | 26 | 92 | +66 | 43% | 0.69× | 0.69 |
| simplifyIR | 3 | 30 | +27 | 18% | 1.38× | 1.17 |
| generateIR | 4 | 19 | +15 | 9% | 0.74× | 0.75 |
| linkAndOptimizeIR (self) | 2 | 16 | +13 | 9% | 1.03× | 1.02 |
| specializeModule | 2 | 14 | +13 | 8% | 1.00× | 0.99 |
Also growing (below top-5): legalizeExistentialTypeLayout (+4 ms, 3%), legalizeResourceTypes (+4 ms, 3%), performForceInlining (+4 ms, 3%).
Near-constant (≤2% of growth each): linkIR (1→4 ms), generateOutput (self) (3→3 ms), parseTranslationUnit (1→3 ms), performMandatoryEarlyInlining (0→2 ms), frontEndExecute (self) (1→0 ms), unrollLoopsInModule (0→0 ms), compileInner (self) (0→0 ms).
| N | compileInner | simplifyIR | linkAndOptimizeIR |
|---|---|---|---|
| 100 | 43 | 3 | 10 |
| 200 | 63 | 5 | 18 |
| 400 | 106 | 12 | 36 |
| 800 | 197 | 30 | 79 |