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[X86] Preserve live SEH state at shared rewrite calls - #5
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A PE32 SEH rewrite can reach one source call through different active scope states. The x86 state pass previously reset that call to the parent base state, and
_setjmp3captured the base state instead of the selected scope.Add a checked, call-site-only
llvm.rewrite.win-x86-seh-inherit-statecontract for ordinary calls in rewrite-owned SEH parents. Calls retain the physical state selected by incoming scope boundaries, and the compiler-owned(buffer, 0)setjmp interface captures a volatile load of that state. State-store hoisting respects an inherited call before a later resetting call.The x86 SEH runtime does not restore callee-saved registers on handler entry. Model this clobber at the EH pad for rewrite-owned SEH parents, including values used only on an exceptional path after a nonreturning call. Native Wine execution reproduced a stale logical frame address in EDI before this fix.
Validation rejects function-level markers, nonempty values, missing noinline, invokes, tail calls, intrinsics, inline assembly, funclet calls, unsupported parents and malformed capture interfaces. Target-specific validation lives in
X86SEHStateCalls.cpp; the public capability macro allows NeverD to refuse this shape with older LLVM builds.Validation: 52 LLVM RUN lines passed, covering O0/O2, optimized IR, SEH3/EH4 generation, handler-only register liveness, predecessor hoisting, malformed contracts and existing callback-state/source-state-order regressions. Both state-reset failures and the handler liveness failure were reproduced before their fixes. NeverD source replay and verifier-clean installation mutations pass for the two new runtime scenarios, with 40 Wine executions covering both patch modes, optimization settings and rebasing. LLVM 22 changed-line formatting and diff checks pass.
The complete NeverD qualification passed: 66 source scenarios and 1,320 Wine executions, followed by an independent 1,320-execution replay; 7,980 C++ tests passed with 51 explicit environment/external-fixture skips and zero failures; 108 Python registration checks and all 309 documentation files passed. The release admission policy passed all eight checks. The older artifact build was cancelled because it lacked the handler register fix. The final package will be built from main under the new r6 tag.