On Thu, 28 Jan 2021 at 08:42, Jakob Bohm <jb-gnumli...@wisemo.com> wrote: > > On 2021-01-27 15:14, Salvatore Mazzarino wrote: > > I’m trying to profile my QEMU process but what I get is a stack full of > unknown. > > I would then need to recompile QEMU with -fno-omit-frame-pointer. > > Do you know if there is a version already built for that purpose? > > I am not sure, but I suspect that compiler-generated frame pointer > code would interfere with the TCG compilation of tiny code snippets > to be pasted together at runtime by the translated code generator.
TCG has not worked by pasting together compiled snippets for many many years now. Compiling QEMU's C code with a frame pointer should be fine. You'll find that the JITted code looks like a single big function (ie there is no internal structure to it) but the entry-to-JIT prologue code should set up the frame pointer correctly so the stack frame looks like C helper function [JITted code] C code that called into JITted code There's no pre-built QEMU that was built with -fno-omit-frame-pointer because it would be pretty useless for anything except debugging QEMU itself, and if you're doing that you want to be working with the QEMU source code rather than a prebuilt binary anyway. You can easily build one yourself using configure's --extra-cflags option. thanks -- PMM
