sl@0: // Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of the License "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: // e32test\math\t_roundtrip.cpp
sl@0: // Tests round-trip convertibility of double->string->double
sl@0: // 
sl@0: //
sl@0: 
sl@0: #define __E32TEST_EXTENSION__
sl@0: #include <e32test.h>
sl@0: #include <e32math.h>
sl@0: 
sl@0: //#define __ALWAYS_PRINT__
sl@0: 
sl@0: RTest test(_L("T_ROUNDTRIP"));
sl@0: 
sl@0: void PrintRealHex(const char* aTitle, const TReal& aIn)
sl@0: 	{
sl@0: 	volatile TUint32* in = (volatile TUint32*)&aIn;
sl@0: #ifdef __DOUBLE_WORDS_SWAPPED__
sl@0: 	TUint32 high = in[0];
sl@0: 	TUint32 low = in[1];
sl@0: #else
sl@0: 	TUint32 high = in[1];
sl@0: 	TUint32 low = in[0];
sl@0: #endif
sl@0: 	TBuf<256> title;
sl@0: 	if (aTitle)
sl@0: 		title.Copy(TPtrC8((const TUint8*)aTitle));
sl@0: 	test.Printf(_L("%S%08x %08x\n"), &title, high, low);
sl@0: 	}
sl@0: 
sl@0: TInt RoundTrip(TReal& aOut, const TReal& aIn)
sl@0: 	{
sl@0: 	TBuf8<64> text;
sl@0: 	TRealFormat fmt;
sl@0: 	fmt.iType = KRealFormatExponent | KRealInjectiveLimit | KUseSigFigs | KDoNotUseTriads | KAllowThreeDigitExp;
sl@0: 	fmt.iWidth = 32;
sl@0: 	fmt.iPlaces = KIEEEDoubleInjectivePrecision;
sl@0: 	fmt.iPoint = '.';
sl@0: #ifdef __ALWAYS_PRINT__
sl@0: 	PrintRealHex("Input : ", aIn);
sl@0: #endif
sl@0: 	TInt r = text.Num(aIn, fmt);
sl@0: 	if (r<0)
sl@0: 		{
sl@0: 		test.Printf(_L("Result %d (Num)\n"), r);
sl@0: 		return r;
sl@0: 		}
sl@0: #ifdef __ALWAYS_PRINT__
sl@0: 	TBuf16<64> text16;
sl@0: 	text16.Copy(text);
sl@0: 	test.Printf(_L("Text  : %S\n"), &text16);
sl@0: #endif
sl@0: 	TLex8 lex(text);
sl@0: 	r = lex.Val(aOut);
sl@0: 	if (r < 0)
sl@0: 		{
sl@0: 		test.Printf(_L("Result %d (Val)\n"), r);
sl@0: 		return r;
sl@0: 		}
sl@0: #ifdef __ALWAYS_PRINT__
sl@0: 	PrintRealHex("Output: ", aOut);
sl@0: #endif
sl@0: 	volatile TUint32* in = (volatile TUint32*)&aIn;
sl@0: 	volatile TUint32* out = (volatile TUint32*)&aOut;
sl@0: 	if (in[0]!=out[0] || in[1]!=out[1])
sl@0: 		{
sl@0: 		test.Printf(_L("Unsuccessful\n"));
sl@0: #ifndef __ALWAYS_PRINT__
sl@0: 		PrintRealHex("Input : ", aIn);
sl@0: 		TBuf16<64> text16;
sl@0: 		text16.Copy(text);
sl@0: 		test.Printf(_L("Text  : %S\n"), &text16);
sl@0: 		PrintRealHex("Output: ", aOut);
sl@0: #endif
sl@0: 		return KErrUnknown;
sl@0: 		}
sl@0: 	return KErrNone;
sl@0: 	}
sl@0: 
sl@0: const TUint64 KMantissaOverflow =	UI64LIT(0x20000000000000);	// 2^53
sl@0: const TUint64 KMantissaThreshold =	UI64LIT(0x10000000000000);	// 2^52
sl@0: 
sl@0: class R
sl@0: 	{
sl@0: public:
sl@0: 	enum {EMinExp=0, EMinNormExp=1, EMaxNormExp=2046, EMaxExp=2047};
sl@0: public:
sl@0: 	R();
sl@0: 	R(const TReal& aIn);
sl@0: 	TReal Value() const;
sl@0: 	TInt Next();
sl@0: 	TInt Prev();
sl@0: public:
sl@0: 	TUint64	iMant;		//	if iExp>0 2^52<=iMant<2^53 else 0<=iMant<2^52
sl@0: 	TInt	iExp;		//	0 < iExp < 2047
sl@0: 	TInt	iSign;
sl@0: 	};
sl@0: 
sl@0: R::R()
sl@0: 	{
sl@0: 	iMant = 0;
sl@0: 	iExp = 0;
sl@0: 	iSign = 0;
sl@0: 	}
sl@0: 
sl@0: R::R(const TReal& aIn)
sl@0: 	{
sl@0: 	const volatile TUint32* in = (const volatile TUint32*)&aIn;
sl@0: #ifdef __DOUBLE_WORDS_SWAPPED__
sl@0: 	TUint32 high = in[0];
sl@0: 	TUint32 low = in[1];
sl@0: #else
sl@0: 	TUint32 high = in[1];
sl@0: 	TUint32 low = in[0];
sl@0: #endif
sl@0: 	iSign = high >> 31;
sl@0: 	iExp = (high >> 20) & EMaxExp;
sl@0: 	iMant = MAKE_TUINT64(high, low);
sl@0: 	iMant <<= 12;
sl@0: 	iMant >>= 12;
sl@0: 	if (iExp)
sl@0: 		iMant += KMantissaThreshold;
sl@0: 	}
sl@0: 
sl@0: TReal R::Value() const
sl@0: 	{
sl@0: 	TUint32 high = iSign ? 1 : 0;
sl@0: 	high <<= 31;
sl@0: 	high |= (iExp<<20);
sl@0: 	TUint32 mh = I64HIGH(iMant);
sl@0: 	mh <<= 12;
sl@0: 	high |= (mh>>12);
sl@0: 	TUint32 low = I64LOW(iMant);
sl@0: 
sl@0: 	union {TReal iReal; TUint32 iX[2];} result;
sl@0: #ifdef __DOUBLE_WORDS_SWAPPED__
sl@0: 	result.iX[0] = high;
sl@0: 	result.iX[1] = low;
sl@0: #else
sl@0: 	result.iX[0] = low;
sl@0: 	result.iX[1] = high;
sl@0: #endif
sl@0: 	return result.iReal;
sl@0: 	}
sl@0: 
sl@0: TInt R::Next()
sl@0: 	{
sl@0: 	if (iExp>0)
sl@0: 		{
sl@0: 		if (++iMant == KMantissaOverflow)
sl@0: 			{
sl@0: 			iMant >>= 1;
sl@0: 			if (++iExp == EMaxExp)
sl@0: 				return KErrOverflow;
sl@0: 			}
sl@0: 		return KErrNone;
sl@0: 		}
sl@0: 	if (++iMant == KMantissaThreshold)
sl@0: 		iExp = 1;
sl@0: 	return KErrNone;
sl@0: 	}
sl@0: 
sl@0: TInt R::Prev()
sl@0: 	{
sl@0: 	if (iExp == EMaxExp)
sl@0: 		{
sl@0: 		if (iMant == KMantissaThreshold)
sl@0: 			{
sl@0: 			--iExp;
sl@0: 			return KErrNone;
sl@0: 			}
sl@0: 		return KErrGeneral;
sl@0: 		}
sl@0: 	if (iExp>0)
sl@0: 		{
sl@0: 		if (--iMant < KMantissaThreshold)
sl@0: 			{
sl@0: 			if (--iExp)
sl@0: 				{
sl@0: 				iMant <<= 1;
sl@0: 				iMant++;
sl@0: 				}
sl@0: 			}
sl@0: 		return KErrNone;
sl@0: 		}
sl@0: 	if (iMant==0)
sl@0: 		return KErrUnderflow;
sl@0: 	--iMant;
sl@0: 	return KErrNone;
sl@0: 	}
sl@0: 
sl@0: void DoTest(R& aR, TInt& aErrorCount)
sl@0: 	{
sl@0: 	TReal out;
sl@0: 	TInt r;
sl@0: 	r = RoundTrip(out, aR.Value());
sl@0: 	if (r==KErrUnknown)
sl@0: 		++aErrorCount;
sl@0: 	R R1(aR);
sl@0: 	R R2(aR);
sl@0: 	if (R1.Next()==KErrNone)
sl@0: 		{
sl@0: 		r = RoundTrip(out, R1.Value());
sl@0: 		if (r==KErrUnknown)
sl@0: 			++aErrorCount;
sl@0: 		}
sl@0: 	if (R2.Prev()==KErrNone)
sl@0: 		{
sl@0: 		r = RoundTrip(out, R2.Value());
sl@0: 		if (r==KErrUnknown)
sl@0: 			++aErrorCount;
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: void DoTest(TInt aExp, TInt& aErrorCount)
sl@0: 	{
sl@0: 	R x;
sl@0: 	x.iExp = aExp;
sl@0: 	x.iMant = KMantissaThreshold;
sl@0: 	if (aExp==0)
sl@0: 		{
sl@0: 		do	{
sl@0: 			x.iMant >>= 1;
sl@0: 			DoTest(x, aErrorCount);
sl@0: 			} while (x.iMant);
sl@0: 		}
sl@0: 	else
sl@0: 		{
sl@0: 		DoTest(x, aErrorCount);
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: void DoTestPow10(TInt aPow, TInt& aErrorCount)
sl@0: 	{
sl@0: 	TReal64 r64;
sl@0: 	TInt r = Math::Pow10(r64, aPow);
sl@0: 	if (r<0)
sl@0: 		return;
sl@0: 	R x(r64);
sl@0: 	DoTest(x, aErrorCount);
sl@0: 	}
sl@0: 
sl@0: void DoTestRandom(TInt& aErrorCount)
sl@0: 	{
sl@0: 	static TInt64 randSeed = I64LIT(0x3333333333333333);
sl@0: 	R x;
sl@0: 	x.iExp = Math::Rand(randSeed) & R::EMaxExp;
sl@0: 	x.iMant = ((TUint64)Math::Rand(randSeed) << 32) | (TUint64)Math::Rand(randSeed);
sl@0: 	while (x.iMant > KMantissaThreshold)
sl@0: 		x.iMant >>= 1;
sl@0: 	x.iSign = Math::Rand(randSeed) & 0x1;
sl@0: 	DoTest(x, aErrorCount);
sl@0: 	}
sl@0: 
sl@0: TInt E32Main()
sl@0: 	{
sl@0: 	test.Title();
sl@0: 	test.Start(_L("Testing conversion from double->string->double"));
sl@0: 
sl@0: 	TInt exp;
sl@0: 	TInt errors = 0;
sl@0: 	test.Next(_L("Test the conversion of powers of 2"));
sl@0: 	for (exp = 0; exp < 2047; ++exp)
sl@0: 		{
sl@0: 		DoTest(exp, errors);
sl@0: 		}
sl@0: 
sl@0: 	test.Next(_L("Test the conversion of powers of 10"));
sl@0: 	for (exp = -325; exp < 325; ++exp)
sl@0: 		{
sl@0: 		DoTestPow10(exp, errors);
sl@0: 		}
sl@0: 
sl@0: 	test.Next(_L("Test the conversion of some random numbers"));
sl@0: 	for (exp = 0; exp < 100; ++exp)
sl@0: 		{
sl@0: 		DoTestRandom(errors);
sl@0: 		}
sl@0: 
sl@0: 	test_Equal(0, errors);
sl@0: 
sl@0: 	test.End();
sl@0: 	return KErrNone;
sl@0: 	}