Stream: git-wasmtime

Topic: wasmtime / PR #9708 winch: Improve frame handling

Wasmtime GitHub notifications bot (Dec 02 2024 at 20:18):

saulecabrera requested abrown for a review on PR #9708.

Wasmtime GitHub notifications bot (Dec 02 2024 at 20:18):

saulecabrera requested wasmtime-compiler-reviewers for a review on PR #9708.

Wasmtime GitHub notifications bot (Dec 02 2024 at 20:18):

saulecabrera opened PR #9708 from saulecabrera:improve-local-management to bytecodealliance:main:

This commit addresses issues identified while working on issue #8091. It improves the frame handling in Winch to prevent subtle bugs and enhance the robustness of the code generation process.

Previously, there was no clear mechanism to verify when the frame was fully set up and safe to access the local slots allocated for register arguments, including the special slots used for the VMContext. As a result, it was possible to inadvertently read from uninitialized memory if calls were made before the frame was properly set up and sealed.

This commit introduces two main changes with the objective to help reduce the risk of introducing bugs related to the above:

• A CodeGenPhase trait, used via the type state pattern to clearly gate the operations allowed during each phase of the code generation process.

• Improve the semantics of locals, by clearly separating the notion of Wasm locals and special locals used by the compiler. This specialization allows a more accurate representation of the semantics of Wasm locals and their index space.

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Wasmtime GitHub notifications bot (Dec 02 2024 at 21:44):

github-actions[bot] commented on PR #9708:

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Wasmtime GitHub notifications bot (Dec 04 2024 at 17:13):

abrown submitted PR review:

Makes sense; sorry for missing this review earlier.

Wasmtime GitHub notifications bot (Dec 04 2024 at 19:00):

saulecabrera updated PR #9708.

Wasmtime GitHub notifications bot (Dec 04 2024 at 19:01):

saulecabrera commented on PR #9708:

Thanks for the review @abrown -- and no worries!

Wasmtime GitHub notifications bot (Dec 04 2024 at 19:03):

saulecabrera has enabled auto merge for PR #9708.

Wasmtime GitHub notifications bot (Dec 04 2024 at 19:28):

saulecabrera merged PR #9708.

Last updated: Dec 23 2024 at 12:05 UTC