[gmh5225]

A rewritten x86 SEH function can capture state 1, activate a finally at state 4, and longjmp back. The existing depth-first scope numbering can map source rows 0,1,2,3,4 to 0,3,4,1,2. MSVC local unwind compares current and saved states numerically, so the generated function stops before running the finally. Preserving enclosing links alone does not preserve this protocol.

For x86 MSVC functions carrying the registration-state rewrite attribute and complete scope identities, order rows by source state before assigning invoke/asynchronous states. Remap enclosing links and pad states together; reject duplicate identities and enclosing states that do not precede their scopes. Keep this logic in separate CodeGen files. Ordinary frontend and incomplete/unannotated graphs retain their existing numbering.

Validation:

• A new regression fails on the previous compiler and passes at O0/O2, with and without IR optimization, with COFF emission. Duplicate identities and invalid enclosing order are rejected.
• Existing callback state assembly, final-image receipt, malformed IR and MC tests pass; the existing EH4 cookie realignment RUN check passes.
• The previously failing five-scope PE32 fixture passes 20 original/reconstructed/product/CLI/rebased executions under Wine with Microsoft x86 CRT. NeverD also independently checks the resulting numeric state order. The full 60-scenario runtime matrix also passed all 1,200 executions in NeverD PR #1016.

[github-actions]

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