On Sat, 20 May 2017, H.J. Lu wrote: > >>>> pushq %whatever > >>>> .cfi_adjust_sp -8 > >>>> ... > >>>> popq %whatever > >>>> .cfi_adjust_sp 8 > >>>> > >> > >> Np. Compiler needs to generate this. > >> > > > > How would the compiler generate this when inline asm is involved? For > > the kernel, objtool could get around the need to have these > > annotations, but not so much for user code? Is the compiler supposed > > to parse the inline asm? Would the compiler provide some magic % code > > to represent the current CFA base register? > > Here is one example of inline asm with call frame info: > > https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/x86_64/sigaction.c;h=be058bac436d1cc9794b2b03107676ed99f6b872;hb=HEAD
That brings us basically pretty close to square one though; having to maintain "manual" anotations. Something we're pretty much trying to avoid through this excercise. -- Jiri Kosina SUSE Labs
