Stream: git-wasmtime

Topic: wasmtime / PR #4680 s390x: Enable object backend

Wasmtime GitHub notifications bot (Aug 10 2022 at 18:52):

uweigand opened PR #4680 from s390x-reloc to main:

This enables the object backend for s390x, in particular the
processing of all required relocations.

This uncovered a bug: we need to use PLT relocations for the
target of calls, which we currently do not. Fixed by adding
a new S390xPLTRel32Dbl reloc type and using it where needed.

FYI - @cfallin @bjorn3
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Wasmtime GitHub notifications bot (Aug 10 2022 at 18:53):

bjorn3 submitted PR review.

Wasmtime GitHub notifications bot (Aug 10 2022 at 18:53):

bjorn3 created PR review comment:

I think this should check is_colocated and use PCRel if true. That is faster than going through the PLT.

Wasmtime GitHub notifications bot (Aug 10 2022 at 18:57):

uweigand created PR review comment:

That's not really necessary; the JIT backend doesn't use PLTs anyway, and when generating object files, the linker will omit PLTs when they are not needed. LLVM also always emits PLT relocations and relies on the linker to optimize them away.

Wasmtime GitHub notifications bot (Aug 10 2022 at 18:57):

uweigand submitted PR review.

Wasmtime GitHub notifications bot (Aug 10 2022 at 19:09):

cfallin submitted PR review.

Wasmtime GitHub notifications bot (Aug 10 2022 at 19:09):

cfallin has enabled auto merge for PR #4680.

Wasmtime GitHub notifications bot (Aug 10 2022 at 20:07):

cfallin merged PR #4680.

Last updated: Dec 23 2024 at 12:05 UTC