Hi Nathan! On 9/29/20 7:58 PM, Nathan Sidwell wrote: > On 9/29/20 11:22 AM, John Paul Adrian Glaubitz wrote: >> >> I'm looking for an information regarding exception handling on Linux/m68k, >> in particular >> I need to know what registers are used by the ABI in order to implement the >> functions >> "getExceptionPointerRegister" and "getExceptionSelectorRegister" in the >> M680x0 backend >> in LLVM [1], [2]. > > I don;t know what those functions are, but from their names they seem to be > related to figuring out the exception object and type?
I think so. I'm not a compiler expert hence my questions :-). > Do you understand the itanium ABI's unwinding mechanism -- > 1) follow stack to get to landing pad. > 2) invoke landing pad to see if it wants to catch > 3) if not, continue following stack > 4) once we've found one to catch it, we need to unwind properly, which > involves invoking cleanups. and eventually getting to the catcher > > invoking the landing pad means passing (a) an integer telling it what's > happening, and (b) a pointer to data. This seems to be the data that I need. I just need to understand how that works. >> I looked into the GCC source code to find the corresponding parts but I >> could only find >> the macros prefixed with "EH_" [4] which I didn't fully understand. > > Those are the bits you want. one of those is the selector (0?) and the other > is the data pointer (1?). OK. But aren't they passed through particular registers on m68k? Or is this something specific to LLVM? Thanks for the help! Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaub...@debian.org `. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
