fix(decoder): element segment and SIMD instruction parsing (#150)#170
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fix(decoder): element segment and SIMD instruction parsing (#150)#170
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…eftype Per WebAssembly spec, element segment flags 1 and 3 use elemkind encoding (0x00 = funcref), not reftype encoding (0x70 = funcref). The decoder was incorrectly matching against reftype bytes, causing modules with (elem declare func ...) to fail with "malformed reference type". Also adds 0x63/0x64 (ref null/ref) encoding support to flags 5, 6, 7 element segment reftype parsing for GC proposal compatibility. Fixes 429 WAST assertion failures (64,068 → 64,497 passing). Trace: skip Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The code body LEB128 validator treated v128.loadN_lane (84-87) and v128.storeN_lane (88-91) the same as plain v128.load ops, missing the trailing lane index byte. This caused the parser to go out of sync with the byte stream, cascading into Truncated LEB128 errors for entire SIMD-heavy modules. Fixes 616 additional WAST assertions (64,497 → 65,113 passing). Trace: skip Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
🔍 Build Diagnostics ReportSummary
🎯 Impact AnalysisIssues in Files You Modified
Cascading Issues (Your Changes Breaking Other Files)
✅ No Issues DetectedPerfect! Your changes don't introduce any new errors or warnings, and don't break any existing code. 📊 Full diagnostic data available in workflow artifacts 🔧 To reproduce locally: # Install cargo-kiln
cargo install --path cargo-kiln
# Analyze your changes
cargo-kiln build --output json --filter-severity error
cargo-kiln check --output json --filter-severity warning |
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Summary
Impact
Baseline: 64,068 pass / 1,574 fail
After: 65,113 pass / 529 fail (+1,045 assertions fixed, -66% failures)
Test plan
cargo check -p kiln-decoder— clean compile🤖 Generated with Claude Code