solidity: mark generated assembly block as memory-safe#99
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The `BytesN` codegen path emits a one-line `mload` inside an `assembly` block to read a fixed-size byte array out of a `bytes memory` argument. The block reads memory only, does not touch the free memory pointer (`0x40`) or the zero slot (`0x60`), and never writes outside the function's allocated memory — so it satisfies the Solidity memory-safety contract documented at https://docs.soliditylang.org/en/latest/assembly.html#memory-safety. Annotating it accordingly lets the IR optimizer spill registers freely. Without the annotation, callers that inline the deserializer tree can hit "stack too deep" once the input contract grows; we observed this in a downstream project where a verifier function inlined enough of the generated deserialization helpers to exceed the 16-slot stack. This is the only `assembly { ... }` emission in the Solidity backend.
deuszx
approved these changes
May 18, 2026
ma2bd
approved these changes
May 18, 2026
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Summary
The
BytesNcodegen path emits a one-linemloadinside anassemblyblock to read a fixed-size byte array out of abytes memoryargument. The block reads memory only, does not touch the free memory pointer (0x40) or the zero slot (0x60), and never writes outside the function's allocated memory — so it satisfies the Solidity memory-safety contract documented athttps://docs.soliditylang.org/en/latest/assembly.html#memory-safety.
Annotating it accordingly lets the IR optimizer spill registers freely. Without the annotation, callers that inline the deserializer tree can hit "stack too deep" once the input contract grows; we observed this in linera-io/linera-protocol#6294.
This is the only
assembly { ... }emission in the Solidity backend.Test Plan
linera-io/linera-protocol#6294 works with this branch of
serde-refliection.