Wasmtime GitHub notifications bot (Sep 11 2025 at 22:31): Wasmtime GitHub notifications bot (Sep 11 2025 at 22:31):uweigand opened PR #11689 from uweigand:s390x-regabi-fix to bytecodealliance:main:
When using the tail-call ABI and the callee needs to pop a non-zero amount of bytes, the stack pointer may never be implicitly restored via the LOAD MULTIPLE instruction in the epilog, but will always be manually updated.
In some rare cases involving exception handling, the epilog for such functions incorrectly did include the stack pointer in the LOAD MULTIPLE list. It turns out that the
is_reg_saved_in_prologue routine did not handle the stack pointer correctly.Note that this only makes any difference for functions where cranelift common code includes the stack pointer in the list of clobbered registers passed to compute_frame_layout, which normally never happens as modifications to the stack pointer should be invisible to common code register tracking ...
Fixes: https://github.com/bytecodealliance/wasmtime/issues/11602
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Wasmtime GitHub notifications bot (Sep 11 2025 at 22:31):uweigand requested abrown for a review on PR #11689.
Wasmtime GitHub notifications bot (Sep 11 2025 at 22:31):uweigand requested wasmtime-compiler-reviewers for a review on PR #11689.
Wasmtime GitHub notifications bot (Sep 11 2025 at 22:31):uweigand requested wasmtime-core-reviewers for a review on PR #11689.
Wasmtime GitHub notifications bot (Sep 11 2025 at 22:31):uweigand requested alexcrichton for a review on PR #11689.
Wasmtime GitHub notifications bot (Sep 11 2025 at 22:57):alexcrichton submitted PR review:
Thanks!
Wasmtime GitHub notifications bot (Sep 11 2025 at 23:20):alexcrichton merged PR #11689.
Last updated: Dec 06 2025 at 06:05 UTC