Port all exception frame management, type identity, and runtime check
functions from C to pure Pascal (blaise_exc.pas). Replace libc
setjmp/longjmp with a minimal custom implementation in x86_64 assembly
(blaise_setjmp_x86_64.s, ~40 lines) that saves only the 8 callee-saved
registers (64-byte jmp_buf vs libc's 200-byte one).
This eliminates the last C source file from the runtime build. The only
non-Pascal code in the runtime is now the assembly setjmp stub.
Changes:
- runtime/src/main/asm/blaise_setjmp_x86_64.s: _blaise_setjmp/_blaise_longjmp
- runtime/src/main/pascal/blaise_exc.pas: _PushExcFrame, _PopExcFrame,
_Raise, _Reraise, _CurrentException, _CurrentExceptionMessage,
_IsInstance, _ImplementsInterface, _GetItab, _Raise_InvalidCast,
_CheckNil — all ported from blaise_exc.c
- uCodeGenQBE.pas: emit call $_blaise_setjmp instead of call $setjmp
- cp.test.exceptions.pas: IR assertion updated for new symbol name
- runtime/Makefile: assembly rule, Pascal blaise_exc build, C rules removed
- .gitignore: whitelist runtime/src/main/asm/*.s
- runtime/src/main/c/blaise_exc.c: deleted
2083 tests pass, fixpoint verified (stage-3/stage-4).
4969b74810