Wasmtime GitHub notifications bot (Mar 03 2026 at 16:15): Wasmtime GitHub notifications bot (Mar 03 2026 at 16:15):theotherjimmy opened PR #12707 from theotherjimmy:z17-lxa to bytecodealliance:main:
Starting with Z17, s390x includes some specialized indexed address computation instruction that allow for computing addresses in a way that could map to finding an element within an array, skipping over a structure header of a constant size. While this does not also load the address, it is usually more efficient, at least in terms of code size, to use this newer load indexed address (lxa, llxa) instruction instead of expanded address computations using add instructions.
This is currently created as a draft, as I'm figuring out how to test this. I think testing is needed, as it's a specific sequence of IR instructions, and while I'm confident that I have them correct, it's better to be certain with testing.
Wasmtime GitHub notifications bot (Mar 03 2026 at 17:46):alexcrichton commented on PR #12707:
cc @uweigand
Wasmtime GitHub notifications bot (Mar 03 2026 at 19:53):github-actions[bot] added the label cranelift on PR #12707.
Wasmtime GitHub notifications bot (Mar 03 2026 at 19:53):github-actions[bot] added the label isle on PR #12707.
Wasmtime GitHub notifications bot (Mar 03 2026 at 19:54):github-actions[bot] commented on PR #12707:
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cc @cfallin, @fitzgen
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Wasmtime GitHub notifications bot (Mar 03 2026 at 20:55):theotherjimmy updated PR #12707.
Wasmtime GitHub notifications bot (Mar 05 2026 at 13:16):theotherjimmy updated PR #12707.
Wasmtime GitHub notifications bot (Mar 05 2026 at 13:17):theotherjimmy commented on PR #12707:
Big refactor to avoid expanding the Inst enum. Still needs some runtests, and running said tests.
Wasmtime GitHub notifications bot (Mar 05 2026 at 13:42):theotherjimmy updated PR #12707.
Wasmtime GitHub notifications bot (Mar 05 2026 at 13:43):theotherjimmy commented on PR #12707:
I added rustfmt check to my auto-test script. Sorry I missed that earlier.
Wasmtime GitHub notifications bot (Mar 12 2026 at 16:04):theotherjimmy updated PR #12707.
Wasmtime GitHub notifications bot (Mar 12 2026 at 16:05):theotherjimmy commented on PR #12707:
I Wrote tests and verified with a Z17 system.
Last updated: Mar 23 2026 at 16:19 UTC