On Wed, Jun 17, 2020 at 4:11 AM Shuai Wang via Gcc <gcc@gcc.gnu.org> wrote:
>
> Hello,
>
> Suppose I have changed certain if condition in the GIMPLE code (generated
> by the `sanopt` pass) into the following format:
>
> if (0 == 1)
> {
> xxxx
> }
>
> Then, in order to completely remove this unnecessary if condition and the
> guarded true branch, I want to leverage the dead code elimination
> optimization of gcc. However, I just cannot figure out a way of doing so. I
> use the following command to output the instrumented GIMPLE code:
A simple CFG cleanup would get rid of the above, if you insert a pass
make sure to return TODO_cfg_cleanup from it.
> gcc -fdump-tree-all -fplugin=./instrumentor.so -g -fsanitize=address test.c
>
> And notice that the instrumented gimple code is right there in the
> outputs: test.c.322t.instrumentor. Everything seems fine.
>
> Anyone could shed some light on how to re-optimize (e.g., with deadcode
> elimination or just use -O3 if possible) the instrumented GIMPLE code?
> Thank you very much.
>
> Shuai
