From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=49698 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PnEzK-0007eq-Pd for qemu-devel@nongnu.org; Wed, 09 Feb 2011 13:42:03 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PnEzJ-0005nP-ER for qemu-devel@nongnu.org; Wed, 09 Feb 2011 13:42:02 -0500 Received: from hall.aurel32.net ([88.191.126.93]:38970) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PnEzJ-0005nE-7k for qemu-devel@nongnu.org; Wed, 09 Feb 2011 13:42:01 -0500 Date: Wed, 9 Feb 2011 19:42:09 +0100 From: Aurelien Jarno Subject: Re: [Qemu-devel] [PATCH v2 4/6] softfloat: Correctly handle NaNs in float16_to_float32() Message-ID: <20110209184209.GE3131@volta.aurel32.net> References: <1297268850-5777-1-git-send-email-peter.maydell@linaro.org> <1297268850-5777-5-git-send-email-peter.maydell@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1297268850-5777-5-git-send-email-peter.maydell@linaro.org> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: Christophe Lyon , qemu-devel@nongnu.org, patches@linaro.org On Wed, Feb 09, 2011 at 04:27:28PM +0000, Peter Maydell wrote: > Correctly handle NaNs in float16_to_float32(), by defining and > using a float16ToCommonNaN() function, as we do with the other formats. > > Signed-off-by: Peter Maydell > --- > fpu/softfloat-specialize.h | 17 +++++++++++++++++ > fpu/softfloat.c | 4 +--- > 2 files changed, 18 insertions(+), 3 deletions(-) Reviewed-by: Aurelien Jarno > diff --git a/fpu/softfloat-specialize.h b/fpu/softfloat-specialize.h > index 4907484..af82359 100644 > --- a/fpu/softfloat-specialize.h > +++ b/fpu/softfloat-specialize.h > @@ -116,6 +116,23 @@ float16 float16_maybe_silence_nan(float16 a) > } > > /*---------------------------------------------------------------------------- > +| Returns the result of converting the half-precision floating-point NaN > +| `a' to the canonical NaN format. If `a' is a signaling NaN, the invalid > +| exception is raised. > +*----------------------------------------------------------------------------*/ > + > +static commonNaNT float16ToCommonNaN( float16 a STATUS_PARAM ) > +{ > + commonNaNT z; > + > + if ( float16_is_signaling_nan( a ) ) float_raise( float_flag_invalid STATUS_VAR ); > + z.sign = a >> 15; > + z.low = 0; > + z.high = ((bits64) a)<<54; > + return z; > +} > + > +/*---------------------------------------------------------------------------- > | Returns the result of converting the canonical NaN `a' to the half- > | precision floating-point format. > *----------------------------------------------------------------------------*/ > diff --git a/fpu/softfloat.c b/fpu/softfloat.c > index 4d51428..735db38 100644 > --- a/fpu/softfloat.c > +++ b/fpu/softfloat.c > @@ -2733,9 +2733,7 @@ float32 float16_to_float32(float16 a, flag ieee STATUS_PARAM) > > if (aExp == 0x1f && ieee) { > if (aSig) { > - /* Make sure correct exceptions are raised. */ > - float32ToCommonNaN(a STATUS_VAR); > - aSig |= 0x200; > + return commonNaNToFloat32(float16ToCommonNaN(a STATUS_VAR) STATUS_VAR); > } > return packFloat32(aSign, 0xff, aSig << 13); > } > -- > 1.7.1 > > > -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurelien@aurel32.net http://www.aurel32.net