Re: [PATCH] inline: do not inline when no_profile_instrument_function is different

[Jan Hubicka <hubicka@ucw.cz>]

> Hello.
> 
> Similarly to e.g. sanitizer attributes, we sould prevent inlining when one function
> is marked as not instrumented. We should do that with -fprofile-generate only.
> 
> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
> 
> Ready to be installed?
> Thanks,
> Martin
> 
> Adds test-case for:
> 	PR gcov-profile/80223
> 
> gcc/ChangeLog:
> 
> 	* ipa-inline.c (can_inline_edge_p): Similarly to sanitizer
> 	options, do not inline when no_profile_instrument_function
> 	attributes are different.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* gcc.dg/no_profile_instrument_function-attr-2.c: New test.
> ---
>  gcc/ipa-inline.c                                  | 10 ++++++++++
>  .../no_profile_instrument_function-attr-2.c       | 15 +++++++++++++++
>  2 files changed, 25 insertions(+)
>  create mode 100644 gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-2.c
> 
> diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
> index 9d896beb2ac..786ab2e7f7f 100644
> --- a/gcc/ipa-inline.c
> +++ b/gcc/ipa-inline.c
> @@ -396,6 +396,16 @@ can_inline_edge_p (struct cgraph_edge *e, bool report,
>        e->inline_failed = CIF_SANITIZE_ATTRIBUTE_MISMATCH;
>        inlinable = false;
>      }
> +  else if (profile_arc_flag
> +	   && lookup_attribute ("no_profile_instrument_function",
> +				DECL_ATTRIBUTES (caller->decl))
> +	      != lookup_attribute ("no_profile_instrument_function",
> +				   DECL_ATTRIBUTES (callee->decl)))
> +    {
> +      e->inline_failed = CIF_UNSPECIFIED;
> +      inlinable = false;
> +    }

Is there reason to prevent the inlining once instrumentation is done?
I think you can just block it for early inliner.

Honza
> +
>    if (!inlinable && report)
>      report_inline_failed_reason (e);
>    return inlinable;
> diff --git a/gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-2.c b/gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-2.c
> new file mode 100644
> index 00000000000..586962a1c76
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-2.c
> @@ -0,0 +1,15 @@
> +/* { dg-require-effective-target global_constructor } */
> +/* { dg-options "-O2 -fprofile-generate -fprofile-update=single -fdump-tree-optimized" } */
> +
> +__attribute__ ((no_profile_instrument_function))
> +int foo()
> +{
> +  return 0;
> +}
> +
> +int bar()
> +{
> +  return foo();
> +}
> +
> +/* { dg-final { scan-tree-dump-times " = foo \\(\\)" 1 "optimized"} } */
> -- 
> 2.32.0
>