bugc: bracket inlined invoke/return to boundary ops in evmgen#235
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Inlined virtual activations mis-rendered in the tracer: the call stack never popped (phantom frames). Root cause was in evmgen lowering, not the optimizer. An IR instruction lowers to N EVM micro-ops, and the generic lowering attaches that instruction's whole operationDebug to every op. That is right for source/variables/transform context (all N ops map to the instruction) but wrong for invoke/return, which are positional activation boundaries: invoke marks one push point, return one pop point. Broadcasting them across the whole op-run makes push/pop reconstruction see every op as both a push and a pop. The optimizer IR is already correctly bracketed (verified per-pass: invoke/return counts are stable through inlining + all L2/L3 passes); the smear appears only after lowering. Real calls are unaffected because their invoke/return ride single-op JUMP/JUMPDEST terminators — only inlined activations put them on multi-op compute instructions. Fix (bracket-activation.ts, wired into block generation): for the ops emitted by one instruction, keep invoke on only the first op and return on only the last op, stripped from the interior; transform markers and source/variables stay on all ops. General evmgen invariant, not inline-specific — a no-op for single-op terminators. Reaches invoke/return nested in pick/gather composites, not just flat leaves. Tests: new inline-bracket.test.ts asserts one push + one pop per site on dbl@2-sites (both=0), invoke-before-return ordering, entry vs exit placement on a multi-instruction body, and unchanged runtime behavior at O0-O3. Full suite green (428 passed).
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Architect's requested safety net for the general invoke/return bracketing invariant: assert it stays a no-op where invoke/return ride single-op carriers. - tailcall back-edge (tailRecursiveSum, O2): the combined invoke+return on the one back-edge JUMP survives (both>=1). - mutually recursive real calls (never inlined): no op carries both, and invoke/return are still present (real call tracing intact).
gnidan
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Jul 3, 2026
…d shapes (#239) Add fixtures for both emission shapes the reconstruction must handle: - bracketed (post #235): invoke on the body's first op, return on the last, transform:["inline"] on all — frame visible across every body op INCLUDING the exit op (close-after), gone at the gap. - legacy smeared: every op carries invoke+return+inline — close-after still yields exactly one frame per body, no accumulation across gap-separated bodies. Verified end-to-end on real O2 (dbl@2 sites, #235 bracketed emission): one virtual frame per body incl. the exit op, top level between/after.
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Fixes the inlined virtual-activation mis-render (#23): the tracer's call
stack never popped (phantom frames) because every op of an inlined body
carried BOTH
invokeandreturn.Root cause — evmgen lowering, not the optimizer
An IR instruction lowers to N EVM micro-ops, and the generic lowering
attaches that instruction's whole
operationDebugto every op. Right forsource/variables/
transform(all N ops map to the instruction) but wrongfor
invoke/return: those are positional activation boundaries (onepush point, one pop point). Broadcasting them across the op-run makes
push/pop reconstruction see every op as both.
Verified per-pass that the optimizer IR stays correctly bracketed through
inlining and all L2/L3 passes (invoke/return counts stable); the smear
appears only after lowering. Real calls are unaffected — their
invoke/return ride single-op JUMP/JUMPDEST terminators; only inlined
activations put them on multi-op compute instructions.
Fix
bracket-activation.ts(wired into block generation): for the ops emittedby one instruction, keep
invokeon only the first op,returnon onlythe last op, stripped from the interior.
transform:["inline"]+source/variables stay on all ops (membership preserved). A general
evmgen invariant, not inline-specific — no-op for single-op terminators
(confirmed: real-call fixtures unchanged). Reaches invoke/return nested in
pick/gathercomposites, not just flat leaves (per architect's note).Tests
New
inline-bracket.test.ts: one push + one pop per site on dbl@2-sites(
both=0), invoke-before-return ordering, entry-vs-exit placement on amulti-instruction body, unchanged runtime at O0–O3. Full bugc suite green
(428 passed, 22 pre-existing skips).
No schema change, no optimizer change, no inlining.ts change.