Re: [edk2-devel] [PATCH v2 00/10] OvmfPkg: add Crypto Driver support

["Ard Biesheuvel" <ardb@kernel.org>]

On Mon, 13 Feb 2023 at 12:39, Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> On Fri, Feb 10, 2023 at 02:46:34PM +0100, Ard Biesheuvel wrote:
> > On Fri, 10 Feb 2023 at 14:42, Ard Biesheuvel <ardb@kernel.org> wrote:
> > >
> > > > Can LTO be enabled for the NOOPT build?  Or depends that on
> > > > optimizations being turned on?
>
> Turns out: kind of.  The crypto driver effectively does
>
>         if (fixed.pcd.bit)
>                 call libcrypt / libopenssl
>         else
>                 throw error
>
> With optimizations turned off altogether gcc will not notice it can
> evaluate the PCD config bits at compile time, which in turn leads to
> everything being compiled in no matter whenever the features are
> enabled or not ...
>
> take care,
>   Gerd
>
> From e0a080ead544813445f731eef137747ff805a5cd Mon Sep 17 00:00:00 2001
> From: Gerd Hoffmann <kraxel@redhat.com>
> Date: Mon, 13 Feb 2023 10:21:50 +0100
> Subject: [PATCH 1/1] CryptoPkg/Driver: enable moderate optimizations for NOOPT
>  builds
>
> With optimizations turned off altogether gcc will not evaluate the
> (constant) configuration PCDs at compile time (see CALL_BASECRYPTLIB
> macro).  Which renders LTO ineffective and leads to huge amounts of
> dead code being included in the crypto driver builds.
>
> Turn on optimizations for GCC, lowest level (-O1), to fix this.
>
> FIXME: visual studio needs that too.
>
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  CryptoPkg/Driver/CryptoDxe.inf | 3 +++
>  CryptoPkg/Driver/CryptoPei.inf | 3 +++
>  CryptoPkg/Driver/CryptoSmm.inf | 3 +++
>  3 files changed, 9 insertions(+)
>
> diff --git a/CryptoPkg/Driver/CryptoDxe.inf b/CryptoPkg/Driver/CryptoDxe.inf
> index 0d08f3a190c8..44921c1fdaa8 100644
> --- a/CryptoPkg/Driver/CryptoDxe.inf
> +++ b/CryptoPkg/Driver/CryptoDxe.inf
> @@ -47,3 +47,6 @@ [Pcd]
>
>  [Depex]
>    TRUE
> +
> +[BuildOptions]
> +  GCC:NOOPT_*_*_CC_FLAGS = -O1

Could we use -Og instead?

> diff --git a/CryptoPkg/Driver/CryptoPei.inf b/CryptoPkg/Driver/CryptoPei.inf
> index dfa1ab58b16f..45704f5f9e42 100644
> --- a/CryptoPkg/Driver/CryptoPei.inf
> +++ b/CryptoPkg/Driver/CryptoPei.inf
> @@ -49,3 +49,6 @@ [Pcd]
>
>  [Depex]
>    TRUE
> +
> +[BuildOptions]
> +  GCC:NOOPT_*_*_CC_FLAGS = -O1
> diff --git a/CryptoPkg/Driver/CryptoSmm.inf b/CryptoPkg/Driver/CryptoSmm.inf
> index 9fe8718823d2..906cf06006f4 100644
> --- a/CryptoPkg/Driver/CryptoSmm.inf
> +++ b/CryptoPkg/Driver/CryptoSmm.inf
> @@ -47,3 +47,6 @@ [Pcd]
>
>  [Depex]
>    TRUE
> +
> +[BuildOptions]
> +  GCC:NOOPT_*_*_CC_FLAGS = -O1
> --
> 2.39.1
>
>
>
> 
>
>