>>> Andy Lutomirski <l...@amacapital.net> 11/04/14 8:40 PM >>> >On 11/04/2014 01:24 AM, Jan Beulich wrote: >> The main obstacle to having done this long ago was the need to >> determine whether annotations are needed in the first place: They need >> to be avoided when a frame pointer got set up. Since I can't see a way >> to determine this before the compilation phase, this is being achieved >> by inspecting the memory address generated by the compiler in an >> interposed assembler macro. Of course this isn't really nice code, and >> this the main reason I'm posting this as RFC only at this point (with >> the hope that maybe someone has an idea of how to achieve the same >> thing in a more elegant way). > >Ask binutils for help?
Binutils know as little about the code the compiler generated as we do. >Is the issue that the CFI annotation you need is different depending on >whether there's a frame pointer or not? No - as said above, they need to be avoided altogether when there's a frame pointer. > If so, can you add some >comments so that mere asm mortals have some prayer of understanding how >your magic works and what the desired output annotations are in the >various cases? Honestly I have a hard time seeing where comments would help here. Plus the difficult part isn't how the annotations look like, but (see above) simply whether to emit them at all. Jan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
