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Date:   Tue, 22 Jun 2021 10:32:42 +0100
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Mark Rutland <mark.rutland@arm.com>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Bill Wendling <morbo@google.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
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Subject: Re: [PATCH 2/2] Kconfig: CC_HAS_NO_PROFILE_FN_ATTR, depend on for
 GCOV and PGO
Message-ID: <20210622093241.GC3555@arm.com>
References: <20210618233023.1360185-1-ndesaulniers@google.com>
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On Tue, Jun 22, 2021 at 10:29:37AM +0100, Mark Rutland wrote:
> On Tue, Jun 22, 2021 at 10:25:34AM +0100, Catalin Marinas wrote:
> > On Mon, Jun 21, 2021 at 01:43:54PM -0700, Nick Desaulniers wrote:
> > > We need to be able to express via Kconfig "GCOV should not be enabled
> > > for architectures that use noinstr when the toolchain does not support
> > > __attribute__((no_profile_instrument_function))."
> > > 
> > > Where "architectures that use noinstr" are currently arm64, s390, and
> > > x86.  So I guess we could do:
> > > 
> > > + depends on !ARM64 || !S390 || !X86 || CC_HAS_NO_PROFILE_FN_ATTR
> > 
> > I think you want:
> > 
> >   depends on !(ARM64 || S390 || X86) || CC_HAS_NO_PROFILE_FN_ATTR
> > 
> > > (We could add a Kconfig for ARCH_WANTS_NO_INSTR, which might be more
> > > informative than listed out architectures which might be non-obvious
> > > to passers-by).
> > 
> > That would probably look better.
> 
> It does; see:
> 
> https://lore.kernel.org/r/20210621231822.2848305-1-ndesaulniers@google.com

I'm getting there, eventually ;).

-- 
Catalin