Section 03: Ori Exception Raise

Context: After Section 02, codegen can reference @ori_eh_personality, but runtime panic emission still uses std::panic::panic_any in ori_panic and ori_panic_cstr. That means Rust panic runtime semantics still drive AOT unwind behavior.

This section moves Itanium AOT panic raising to Ori-owned exception objects via _Unwind_RaiseException.

Critical correctness constraints:

• ori_panic/ori_panic_cstr are exported FFI entrypoints that may unwind, so their ABI must remain extern "C-unwind".
• ori_raise_exception does not need a JIT mapping entry unless LLVM IR directly calls it.
• Windows MSVC compatibility path (ori_try_call + catch_unwind) must remain explicitly handled.

03.1 Exception Object & Raise Function

File(s): compiler/ori_rt/src/eh_personality.c (MODIFY)

• Define Ori exception class and object header: (2026-03-03)

  #define ORI_EXCEPTION_CLASS 0x4f524900504e4300ULL
  
  typedef struct {
      struct _Unwind_Exception header;
  } OriException;

• Implement cleanup callback for caught exceptions: (2026-03-03)

  static void ori_exception_cleanup(
      _Unwind_Reason_Code reason,
      struct _Unwind_Exception *exc)
  {
      (void)reason;
      free(exc);
  }

• Implement _Unwind_RaiseException bridge: (2026-03-03)

  __attribute__((noreturn))
  void ori_raise_exception(void) {
      OriException *exc = (OriException *)malloc(sizeof(OriException));
      if (!exc) {
          fprintf(stderr, "ori: fatal — out of memory during panic\n");
          abort();
      }
      memset(exc, 0, sizeof(*exc));
      exc->header.exception_class = ORI_EXCEPTION_CLASS;
      exc->header.exception_cleanup = ori_exception_cleanup;
  
      _Unwind_Reason_Code result = _Unwind_RaiseException(&exc->header);
  
      free(exc);
      fprintf(stderr,
          "ori: fatal — _Unwind_RaiseException returned (code %d)\n",
          (int)result);
      abort();
  }

• Ensure required includes are present: <stdlib.h>, <stdio.h>, <string.h>, <unwind.h>. (2026-03-03)

• Keep function externally visible (no static). (2026-03-03) — nm confirms T ori_raise_exception (global text symbol)

03.2 Runtime Panic Integration

File(s): compiler/ori_rt/src/io.rs, compiler/ori_rt/src/lib.rs (MODIFY)

• Add FFI declaration in io.rs: (2026-03-03) — #[cfg(not(all(target_os = "windows", target_env = "msvc")))]

  extern "C" {
      fn ori_raise_exception() -> !;
  }

• Update AOT Itanium panic path in both functions (ori_panic, ori_panic_cstr) to call: (2026-03-03) — via aot_raise_exception() helper with cfg-gated implementations

  unsafe { ori_raise_exception() }

  after panic message TLS storage and JIT longjmp fast path handling.

• Keep ABI as extern "C-unwind" for ori_panic and ori_panic_cstr. (2026-03-03)

• Remove stale comments that describe the default AOT path as panic_any. (2026-03-03) — updated assert doc, panic dispatch doc

• Update lib.rs comments around OriPanic/ori_run_main so they no longer claim unconditional panic_any-based AOT behavior. (2026-03-03) — OriPanic documented as MSVC-only, ori_run_main documented as not in LLVM call chain

03.3 Target Gating and Compatibility

File(s): compiler/ori_rt/src/io.rs, compiler/ori_rt/src/lib.rs (MODIFY)

• Gate behavior by target model: (2026-03-03) — aot_raise_exception() with #[cfg] dispatch

  • Itanium-oriented targets: use ori_raise_exception.
  • Windows MSVC compatibility path: keep panic_any behavior until a dedicated SEH migration replaces ori_try_call/catch_unwind coupling.

• Keep OriPanic only as long as needed for MSVC compatibility path; mark/document it accordingly. (2026-03-03) — doc comment updated to state MSVC-only scope

• Do not add ori_raise_exception to runtime_mappings.rs unless LLVM IR starts calling that symbol directly. (2026-03-03) — confirmed not added, no JIT mapping needed

Rationale:

• JIT mapping table exists for symbols called by JIT-generated LLVM IR.
• ori_raise_exception is an internal call from runtime Rust code (ori_panic*), so normal static linking resolves it without MCJIT symbol registration.

03.4 Completion Checklist

• ori_raise_exception exists in eh_personality.c and is __attribute__((noreturn)) (2026-03-03)
• nm target/debug/libori_rt.a | grep ori_raise_exception shows the symbol (2026-03-03) — T ori_raise_exception
• ori_panic and ori_panic_cstr remain extern "C-unwind" (2026-03-03)
• Itanium AOT panic path no longer uses panic_any (2026-03-03) — uses ori_raise_exception() via aot_raise_exception()
• rg -n "panic_any" compiler/ori_rt/src/io.rs returns only MSVC-guarded compatibility matches (2026-03-03) — 1 match at line 279 inside #[cfg(all(target_os = "windows", target_env = "msvc"))]
• cargo build -p ori_rt succeeds (2026-03-03)
• cargo test -p ori_rt succeeds (2026-03-03) — 329/329 pass

Exit Criteria: Itanium AOT panic raising is Ori-owned (_Unwind_RaiseException via ori_raise_exception), ABI correctness is preserved (extern "C-unwind" on panic entrypoints), and any remaining panic_any usage is explicitly MSVC compatibility-scoped and documented.