On Wed, Oct 2, 2019 at 9:52 PM Fangrui Song <i...@maskray.me> wrote: > > On 2019-09-24, Martin Liška wrote: > >On 9/19/19 10:33 AM, Martin Liška wrote: > >> - One needs modified binutils and I that would probably require a > >> configure detection. The only way > >> which I see is based on ld --version. I'm planning to make the binutils > >> submission soon. > > > >The patch submission link: > >https://sourceware.org/ml/binutils/2019-09/msg00219.html > > Hi Martin, > > I have a question about why .text.sorted.* are needed. > > The Sony presentation (your [2] link) embedded a new section > .llvm.call-graph-profile[3] to represent edges in the object files. The > linker (lld) collects all .llvm.call-graph-profile sections and does a > C3 layout. There is no need for new section type .text.sorted.* > > [3]: > https://github.com/llvm/llvm-project/blob/master/lld/test/ELF/cgprofile-obj.s > > (Please CC me. I am not subscribed.)
The idea of GCC's version is to that the modification needed to the linker is very little. And even without patching the linker script/linker, you don't need to much special and you don't need LD to do much work at all. Thanks, Andrew
