Re: Fwd: [PATCH, doc/ARM] Remove false affirmation that Thumb cannot use an FPU

[Thomas Preudhomme <thomas dot preudhomme at foss dot arm dot com>]

Hi Sandra,

Thanks for your feedback. Please find an updated version attached to this email. 
ChangeLog entry is unchanged:

*** gcc/ChangeLog ***

2016-08-02  Thomas Preud'homme  <thomas.preudhomme@arm.com>

        * doc/fragments.texi (MULTILIB_EXCEPTIONS): Replace example with
        preventing combination of -mfloat-abi=soft with any -mfpu option.

Best regards,

Thomas

On 11/08/16 04:09, Sandra Loosemore wrote:
> On 08/10/2016 09:51 AM, Thomas Preudhomme wrote:
>
> > diff --git a/gcc/doc/fragments.texi b/gcc/doc/fragments.texi
> > index
> > b6d8541c8ca820fa732363a05221e2cd4d1251c2..a060635c9cee7374d9d187858ac87acdd08860f2
> > 100644
> > --- a/gcc/doc/fragments.texi
> > +++ b/gcc/doc/fragments.texi
> > @@ -117,12 +117,15 @@ specified, there are combinations that should not be
> > built.  In that
> >  case, set @code{MULTILIB_EXCEPTIONS} to be all of the switch exceptions
> >  in shell case syntax that should not be built.
> >
> > -For example the ARM processor cannot execute both hardware floating
> > -point instructions and the reduced size THUMB instructions at the same
> > -time, so there is no need to build libraries with both of these
> > -options enabled.  Therefore @code{MULTILIB_EXCEPTIONS} is set to:
> > +For example on ARM targets @code{-mfloat-abi=soft} requests to use a
> > +softfloat implementation for floating-point operations.  Therefore, it
>
> For example, on ARM targets @option{-mfloat-abi=soft} requests use of software
> floating-point operations.  Therefore, it
>
> > +does not make sense to find both @code{-mfloat-abi=soft} and an
>
> @option here too
>
> > +@code{mfpu} option on the command line so @code{MULTILIB_EXCEPTIONS}
>
> and here @option{-mfpu}
>
> > +could contain the following exception (assuming that @code{-mfloat-abi}
>
> @option
>
> > +comes after in MULTILIB_OPTIONS and given that soft is the default
>
> @code markup on MULTILIB_OPTIONS?
> @samp markup on soft?
>
> > +value):
> >  @smallexample
> > -*mthumb/*mhard-float*
> > +*mfpu=*
> >  @end smallexample
> >
> >  @findex MULTILIB_REQUIRED
>
> -Sandra
diff --git a/gcc/doc/fragments.texi b/gcc/doc/fragments.texi
index b6d8541c8ca820fa732363a05221e2cd4d1251c2..abf4e128671bb4751d21f24bb69625593d3c839e 100644
--- a/gcc/doc/fragments.texi
+++ b/gcc/doc/fragments.texi
@@ -117,12 +117,15 @@ specified, there are combinations that should not be built.  In that
 case, set @code{MULTILIB_EXCEPTIONS} to be all of the switch exceptions
 in shell case syntax that should not be built.
 
-For example the ARM processor cannot execute both hardware floating
-point instructions and the reduced size THUMB instructions at the same
-time, so there is no need to build libraries with both of these
-options enabled.  Therefore @code{MULTILIB_EXCEPTIONS} is set to:
+For example on ARM targets @option{-mfloat-abi=soft} requests to use a
+softfloat implementation for floating-point operations.  Therefore, it
+does not make sense to find both @option{-mfloat-abi=soft} and an
+@option{mfpu} option on the command line so @code{MULTILIB_EXCEPTIONS}
+could contain the following exception (assuming that
+@option{-mfloat-abi} comes after in @code{MULTILIB_OPTIONS} and given
+that @option{-mfloat-abi=soft} is the default value):
 @smallexample
-*mthumb/*mhard-float*
+*mfpu=*
 @end smallexample
 
 @findex MULTILIB_REQUIRED