Stream: git-wasmtime

Topic: wasmtime / PR #5201 fuzzgen: Add a few more ops

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 14:50):

afonso360 opened PR #5201 from fuzz-more-ops-2 to main:

:wave: Hey,

This adds bitselect,select and select_spectre_guard to the fuzzgen list of ops.

Fuzzing on x86 & AArch64 for the past couple of hours has not raised any issues.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:22):

jameysharp submitted PR review.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:22):

jameysharp created PR review comment:

Could you add links to #5199 and #5200 here?

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:22):

jameysharp created PR review comment:

I'm a little hesitant to add opcodes to this list where we have to disable all versions of the opcode on all of the architectures that we're actually fuzzing on. I suppose we could add an insert_select_spectre_guard function that generates an icmp first. It's not great in the long run, since I like your idea of eventually generating this table from the meta instruction definitions. But it would get us some more fuzz test coverage quickly, at least.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:22):

jameysharp created PR review comment:

Based on your report in #5200, shouldn't these select.i128 opcodes exclude aarch64 as well?

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:22):

jameysharp submitted PR review.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:22):

jameysharp created PR review comment:

Could you add links to #5197 and #5198 here?

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:24):

afonso360 updated PR #5201 from fuzz-more-ops-2 to main.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:29):

afonso360 submitted PR review.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:29):

afonso360 created PR review comment:

Yeah, I don't mind adding that right now.

I didn't open issues for select_spectre_guard since I wasn't sure, but are we planning on implementing that? Or does that opcode only make sense when paired with something else?

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 17:29):

afonso360 edited PR review comment.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 19:19):

jameysharp submitted PR review.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 04 2022 at 19:19):

jameysharp created PR review comment:

That's a good question! I've opened #5206 for it.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 05 2022 at 12:59):

afonso360 updated PR #5201 from fuzz-more-ops-2 to main.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 05 2022 at 13:21):

afonso360 submitted PR review.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 05 2022 at 13:21):

afonso360 created PR review comment:

:+1: Thanks!

I've added the special insert_select_spectre_guard, and surprisingly this works for all variations of select_spectre_guard.

I'll wait for a decision to be reached on #5206 before opening the "missing lowerings" issues.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 07 2022 at 17:08):

jameysharp submitted PR review.

view this post on Zulip Wasmtime GitHub notifications bot (Nov 07 2022 at 17:08):

jameysharp merged PR #5201.

Last updated: Dec 23 2024 at 13:07 UTC