Re: [PATCH 7/7] DWARF: add the config option
From: Jiri Kosina
Date: Mon May 22 2017 - 07:34:34 EST
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:
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.