Stream: git-wasmtime

Topic: wasmtime / PR #8059 winch: Fix the bounds check for dynam...

Wasmtime GitHub notifications bot (Mar 07 2024 at 13:37):

saulecabrera opened PR #8059 from saulecabrera:winch-use-index-offset-and-access-for-bounds-checks to bytecodealliance:main:

This commit fixes the bounds check comparison for dynamic heaps. The previous implementation wasn't using the right value: for the general case of dynamic heaps, we want to compare if

  index + offset + access_size > bounds

But it was only comparing

 index > bounds

This commit addresses the issue by adding a new temporary register into the equation which will be used for the bounds check comparison and for overflow checks. This approach is preferred over using the scratch register because it's harder to know when the scratch register might get clobbered (in the case of spectre checks, it could for example)

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Wasmtime GitHub notifications bot (Mar 07 2024 at 13:37):

saulecabrera requested fitzgen for a review on PR #8059.

Wasmtime GitHub notifications bot (Mar 07 2024 at 13:37):

saulecabrera requested wasmtime-compiler-reviewers for a review on PR #8059.

Wasmtime GitHub notifications bot (Mar 07 2024 at 13:37):

saulecabrera requested wasmtime-core-reviewers for a review on PR #8059.

Wasmtime GitHub notifications bot (Mar 07 2024 at 15:44):

github-actions[bot] commented on PR #8059:

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Wasmtime GitHub notifications bot (Mar 07 2024 at 16:16):

fitzgen submitted PR review.

Wasmtime GitHub notifications bot (Mar 07 2024 at 16:16):

fitzgen commented on PR #8059:

Thanks!

Wasmtime GitHub notifications bot (Mar 07 2024 at 16:41):

fitzgen merged PR #8059.

Last updated: Nov 22 2024 at 17:03 UTC