OK, I think I know how to solve it. Just return TODO_update_ssa
<https://code.woboq.org/gcc/gcc/tree-pass.h.html#249>.
On Sun, Jun 21, 2020 at 5:34 PM Shuai Wang <wangshuai...@gmail.com> wrote:
> Hello,
>
> I am doing instrumentation of GIMPLE code by adding extra coverage
> counters at each basic block. Basically it's
> mimicking -fsanitize-coverage=trace-pc, where the only difference is
> that __sanitizer_cov_trace_pc (the default
> hander of fsanitize-coverage=trace-pc) has no input parameters, but my
> coverage hander has a parameter of basic block id.
>
> My current issue is that after the instrumentation of one function, the
> plugin throws an exception at the following gcc_assert and do not proceed
> to instrument another function:
>
> if (flags & TODO_cleanup_cfg)
> cleanup_tree_cfg (flags & TODO_update_ssa_any);
> else if (flags & TODO_update_ssa_any)
> update_ssa (flags & TODO_update_ssa_any);
> gcc_assert (!need_ssa_update_p (fn)); <---------- line 1954 of
> gcc/passes.c for gcc 10.1.0
>
> This really confused me, because when I print out the instrumented GIMPLE
> code and compare with fsanitize-coverage=trace-pc, I don't see a major
> difference here:
>
> ====== my instrumented GIMPLE code ===========
>
> fun2 ()
> {
> int D.2588;
> int _3;
>
> <bb 2> :
> __sanitizer_cov_trace_pc (2); <--- my coverage hander with basic block id
> as the input
> __builtin_puts (&"fun2"[0]);
> _3 = 0;
>
> <bb 3> :
> <L0>:
> __sanitizer_cov_trace_pc (3);
> return _3;
>
> }
>
> ======= the corresponding instrumented GIMPLE code by
> fsanitize-coverage=trace-pc =====
>
> fun2 ()
> {
> int D.2760;
> int _3;
>
> <bb 2> [0.00%]:
> __builtin___sanitizer_cov_trace_pc ();
> __builtin_puts (&"fun2"[0]);
> _3 = 0;
>
> <L0> [0.00%]:
> __builtin___sanitizer_cov_trace_pc ();
> return _3;
>
> }
>
> There is no big difference here. Could anyone shed some lights on why an
> exception on "need_ssa_update_p" is thrown? I don't think there is an need to
> udpate any "SSA" here.. Thank you very much.
>
> Best,
>
> Shuai
>
>
