fix(fused): preserve element-section segment-count on remap (closes #172, v1.1.11)#173
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) The fused component pass invalidated core modules that have an element segment: after removing a dead function it rebuilds the element section (remap_element_section_refs) and extracts the raw payload to store in element_section_bytes. wasm_encoder's Encode::encode writes a length-prefixed BODY (<LEB128 len><payload>), NOT a full <id><len><payload> section — but the extraction skipped a phantom section-id byte, stripping the leading <segment-count> off the payload. The count-less segment then re-validated as "section size mismatch: unexpected data at the end of the section", so loom fail-safe-fell-back to the original bytes — leaving the largest core module of gale's falcon-flight component at ~0% optimization. Fix: strip only the leading LEB128 length, from offset 0. Verified on gale's exact artifact (falcon-flight-v1.34.wasm, sha256 3213a135…): all 4 core modules now optimize (was 3/4), component 0.2% → 3.9% (core module 0: 96.5KB → 92.6KB), wasm-tools validate passes. New test_remap_element_section_preserves_segment_count; 393 lib + 85 integration tests pass. Bumps 1.1.10 -> 1.1.11. Closes #172. Trace: REQ-12
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gale #172 — fused pass invalidates core modules with element segments
The fused component pass fail-safe-fell-back on falcon-flight's core module 0 (~96 KB, the hot one), leaving it at ~0% optimization.
Root cause
After removing a dead function, the pass rebuilds the element section (
remap_element_section_refs) and extracts the raw payload forelement_section_bytes.wasm_encoder'sEncode::encodewrites a length-prefixed body (<LEB128 len><payload>) — no section-id byte. The extraction assumedid + len + payloadand skipped a phantom id byte, stripping the leading<segment-count>off the payload. The count-less segment re-validated assection size mismatch: unexpected data at the end of the section.Fix
Strip only the leading LEB128 length, from offset 0.
Verified on gale's exact artifact
falcon-flight-v1.34.wasm(sha2563213a135…): all 4/4 core modules now optimize (was 3/4), component 0.2% → 3.9% (core module 0: 96.5 KB → 92.6 KB),wasm-tools validatepasses. Newtest_remap_element_section_preserves_segment_count; 393 lib + 85 integration tests pass.Known-red gates (pre-existing, unrelated)
Closes #172.
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