Support dynamic array event sources

[Th0rgal]

Summary

• allow event encoding to source uint256[]-style dynamic array payloads from memory-backed locals and projected dynamic members
• validate the new event argument sentinel forms for supported dynamic array element types
• lower macro emit arguments for memory arrays and projected dynamic arrays to the compilation model event-source expressions
• add compilation-model feature coverage for memory-backed and projected event array sources

Notes

This extends the encoder/model path needed for source-shaped dynamic array event payloads. The current executable surface still has , so fully source-level heterogeneous event argument lists remain a separate follow-up.

Verification

• git diff --check
• lake build Compiler.CompilationModelFeatureTest
• lake build PrintAxioms
• python3 scripts/generate_print_axioms.py --check
• python3 scripts/check_axioms.py

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Note

Medium Risk
Extends event ABI encoding/validation for dynamic arrays and changes macro lowering of emit arguments, which can affect generated Yul for event payloads and topic hashing. Scope is limited to dynamic-array event args, with added feature tests to catch regressions.

Overview
Enables event emission to source uint256[]-style dynamic array payloads not only from direct parameters, but also from memory-backed locals and projected dynamic members (via new sentinel Expr.*Length forms), by plumbing a unified EventDynamicArraySource into both indexed-topic hashing and unindexed data encoding.

Adds validation for these new event-argument shapes, updates the Verity macro so emit lowers eligible array expressions into the new sentinels, and adds compilation-model feature tests that ensure both memory and projected dynamic array sources compile.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Wrong base offset for param array event source

High Severity

In eventDynamicArraySource?, the Expr.param name case sets dataOffsetExpr to indexedDynamicBaseOffsetExpr dynamicSource name, which resolves to {name}_abs_offset (the position of the array's length word). The old code used YulExpr.ident s!"{name}_data_offset", which points 32 bytes later to the first data element. Since dataOffsetExpr is used as the base for element iteration (dataOffsetExpr + i * elemWordSize), every element read is off by −32 bytes — element 0 reads the length word itself, and all subsequent reads are shifted.

Additional Locations (2)

• Compiler/CompilationModel/EventEmission.lean#L353-L354
• Compiler/CompilationModel/EventEmission.lean#L546-L547

 

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