Stream: git-wasmtime

Topic: wasmtime / PR #12644 cranelift/x64: implement cls for all...

Wasmtime GitHub notifications bot (Feb 24 2026 at 03:35):

shreyasravi320 requested alexcrichton for a review on PR #12644.

Wasmtime GitHub notifications bot (Feb 24 2026 at 03:35):

shreyasravi320 requested wasmtime-compiler-reviewers for a review on PR #12644.

Wasmtime GitHub notifications bot (Feb 24 2026 at 03:35):

shreyasravi320 opened PR #12644 from shreyasravi320:cls-impl-x86_64 to bytecodealliance:main:

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Fixes issue #5107
cls implemented with the identity cls(x) = clz(x ^ (x >> 1)) - 1
All integer types (i8, i16, i32, i64, and i128) handled
Added tests to filetests

Wasmtime GitHub notifications bot (Feb 24 2026 at 07:03):

github-actions[bot] added the label cranelift:area:x64 on PR #12644.

Wasmtime GitHub notifications bot (Feb 24 2026 at 07:03):

github-actions[bot] added the label cranelift on PR #12644.

Wasmtime GitHub notifications bot (Feb 24 2026 at 17:47):

shreyasravi320 edited PR #12644:

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Fixes #5107
cls implemented with the identity cls(x) = clz(x ^ (x >> 1)) - 1
All integer types (i8, i16, i32, i64, and i128) handled
Added tests to filetests

Wasmtime GitHub notifications bot (Feb 24 2026 at 20:32):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Feb 24 2026 at 20:32):

alexcrichton created PR review comment:

These two rules can be merged together through the x64_sar helper perhaps?

Wasmtime GitHub notifications bot (Feb 24 2026 at 20:32):

alexcrichton created PR review comment:

For runnable tests we typically use the runtest directory instead of isa/x64. I see as well there's already a cls.clif file in that directory, so can that file be enabled for x64, and perhaps these tests merged there too?

Wasmtime GitHub notifications bot (Feb 24 2026 at 23:21):

shreyasravi320 updated PR #12644.

Wasmtime GitHub notifications bot (Feb 24 2026 at 23:22):

shreyasravi320 submitted PR review.

Wasmtime GitHub notifications bot (Feb 24 2026 at 23:22):

shreyasravi320 created PR review comment:

Got it. Added x86 support in the cls test there, and added the i128 tests. The existing tests were pretty comprehensive so I just added the i128 tests in the same format.

Wasmtime GitHub notifications bot (Feb 24 2026 at 23:24):

shreyasravi320 submitted PR review.

Wasmtime GitHub notifications bot (Feb 24 2026 at 23:24):

shreyasravi320 created PR review comment:

Sounds good. I decided to keep x64_sarq_mi in the cls rule for i128 since it would be more effort to switch that over to x64_sar.

Wasmtime GitHub notifications bot (Feb 25 2026 at 15:16):

alexcrichton commented on PR #12644:

There's a separate i128-cls.clif as well which I believe has a specific option to get it to work with s390x. Given all backends now implement cls for i128 (I think given the test report), want to merge that test into cls.clif? I think adding in the set enable_multi_ret_implicit_sret option for s390x might fix CI as a side effect too.

Wasmtime GitHub notifications bot (Feb 25 2026 at 16:51):

shreyasravi320 updated PR #12644.

Wasmtime GitHub notifications bot (Feb 25 2026 at 18:55):

alexcrichton submitted PR review:

Thanks!

Wasmtime GitHub notifications bot (Feb 25 2026 at 18:55):

alexcrichton added PR #12644 cranelift/x64: implement cls for all integer types to the merge queue.

Wasmtime GitHub notifications bot (Feb 25 2026 at 19:40):

alexcrichton merged PR #12644.

Wasmtime GitHub notifications bot (Feb 25 2026 at 19:40):

alexcrichton removed PR #12644 cranelift/x64: implement cls for all integer types from the merge queue.

Last updated: Mar 23 2026 at 16:19 UTC