We need a way to pass flags to rombuilds in Raptor via extension flm interfaces, so that the CPP pass
of the rom input files can be informed what toolchain we are building with and conditionally
include or exclude files depending on whether the toolchain could build them.
// Copyright (c) 1995-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of the License "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
// e32\euser\maths\um_sqrt.cpp
// Square root.
//
//
#include "um_std.h"
#if defined(__USE_VFP_MATH) && !defined(__CPU_HAS_VFP)
#error __USE_VFP_MATH was defined but not __CPU_HAS_VFP - impossible combination, check variant.mmh
#endif
#ifndef __USE_VFP_MATH
#ifndef __REALS_MACHINE_CODED__
LOCAL_D const TUint32 KConstAdata[] = {0x00000000,0xD5A9A805,0x7FFD0000};
LOCAL_D const TUint32 KConstBdata[] = {0x00000000,0x9714B9CB,0x7FFE0000};
LOCAL_D const TUint32 Sqr2Invdata[] = {0xF9DE6484,0xB504F333,0x7FFE0000}; // 1/sqr2
EXPORT_C TInt Math::Sqrt(TReal& aTrg,const TReal &aSrc)
/**
Calculates the square root of a number.
@param aTrg A reference containing the result.
@param aSrc The number whose square-root is required.
@return KErrNone if successful, otherwise another of
the system-wide error codes.
*/
//
// Fast sqrt routine. See Software manual by W.J.Cody & W.Waite Chapter 4.
//
{
const TRealX& KConstA=*(const TRealX*)KConstAdata;
const TRealX& KConstB=*(const TRealX*)KConstBdata;
const TRealX& Sqr2Inv=*(const TRealX*)Sqr2Invdata;
TRealX x;
TInt r=x.Set(aSrc);
if (x.IsZero())
{
aTrg=aSrc;
return(KErrNone);
}
if (r==KErrArgument || x.iSign&1)
{
SetNaN(aTrg);
return(KErrArgument);
}
if (r==KErrOverflow) // positive infinity
{
aTrg=aSrc;
return(r);
}
TInt n=x.iExp-0x7FFE;
x.iExp=0x7FFE;
TRealX y=KConstB*x+KConstA;
y=y+(x/y);
y.iExp--;
y=y+(x/y);
y.iExp--;
y=y+(x/y);
y.iExp--;
if (n&1)
{
y*=Sqr2Inv;
n++;
}
y.iExp=TUint16(TInt(y.iExp)+(n>>1));
return y.GetTReal(aTrg);
}
#endif
#endif // !__USE_VFP_MATH - VFP version is in assembler