sl@0: /*
sl@0: * Copyright (c) 2003-2009 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: *
sl@0: */
sl@0: 
sl@0: 
sl@0: /**
sl@0:  @file 
sl@0:  @internalComponent
sl@0: */
sl@0:  
sl@0: #ifndef __BIGINT_WORDS_H__
sl@0: #define __BIGINT_WORDS_H__
sl@0: 
sl@0: #include "../common/inlines.h"
sl@0: 
sl@0: inline void ArraySetBit(TUint* aS, TUint aJ)
sl@0: 	{
sl@0: 	aS[aJ/WORD_BITS] |= (1L << (aJ%WORD_BITS));
sl@0: 	}
sl@0: 
sl@0: inline TUint CountWords(const TUint *X, TUint N)
sl@0: 	{
sl@0: 	while (N && X[N-1]==0)
sl@0: 		N--;
sl@0: 	return N;
sl@0: 	}
sl@0: 
sl@0: inline void SetWords(TUint *r, TUint a, TUint n)
sl@0: 	{
sl@0: 	Mem::Fill(r, WordsToBytes(n), a);
sl@0: 	}
sl@0: 
sl@0: inline void CopyWords(TUint *r, const TUint *a, TUint n)
sl@0: 	{
sl@0: 	Mem::Copy(r, a, WordsToBytes(n));
sl@0: 	}
sl@0: 
sl@0: inline TUint ShiftWordsLeftByBits(TUint *r, TUint n, TUint shiftBits)
sl@0: 	{
sl@0: 	assert (shiftBits<WORD_BITS);
sl@0: 	TUint u, carry=0;
sl@0: 	if (shiftBits)
sl@0: 		for (TUint i=0; i<n; i++)
sl@0: 			{
sl@0: 			u = r[i];
sl@0: 			r[i] = (u << shiftBits) | carry;
sl@0: 			carry = u >> (WORD_BITS-shiftBits);
sl@0: 			}
sl@0: 	return carry;
sl@0: 	}
sl@0: 
sl@0: inline TUint ShiftWordsRightByBits(TUint *r, TUint n, TUint shiftBits)
sl@0: {
sl@0: 	assert (shiftBits<WORD_BITS);
sl@0: 	TUint u, carry=0;
sl@0: 	if (shiftBits)
sl@0: 		for (int i=n-1; i>=0; i--)
sl@0: 			{
sl@0: 			u = r[i];
sl@0: 			r[i] = (u >> shiftBits) | carry;
sl@0: 			carry = u << (WORD_BITS-shiftBits);
sl@0: 			}
sl@0: 	return carry;
sl@0: 	}
sl@0: 
sl@0: inline TUint CryptoMin(TUint aLeft, TUint aRight) 
sl@0: 	{
sl@0: 	return(aLeft<aRight ? aLeft : aRight);
sl@0: 	}
sl@0: 
sl@0: inline TUint CryptoMax(TUint aLeft, TUint aRight)
sl@0: 	{
sl@0: 	return(aLeft<aRight ? aRight : aLeft);
sl@0: 	}
sl@0: 
sl@0: inline void ShiftWordsLeftByWords(TUint *r, TUint n, TUint shiftWords)
sl@0: 	{
sl@0: 	shiftWords = CryptoMin(shiftWords, n);
sl@0: 	if (shiftWords)
sl@0: 		{
sl@0: 		for (TUint i=n-1; i>=shiftWords; i--)
sl@0: 			r[i] = r[i-shiftWords];
sl@0: 		SetWords(r, 0, shiftWords);
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: inline void ShiftWordsRightByWords(TUint *r, TUint n, TUint shiftWords)
sl@0: 	{
sl@0: 	shiftWords = CryptoMin(shiftWords, n);
sl@0: 	if (shiftWords)
sl@0: 		{
sl@0: 		for (TUint i=0; i+shiftWords<n; i++)
sl@0: 			r[i] = r[i+shiftWords];
sl@0: 		SetWords(r+n-shiftWords, 0, shiftWords);
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: inline TUint BytePrecision(TUint aValue)
sl@0: 	{
sl@0: 	TUint x=4;
sl@0: 	if(aValue < 0x10000) aValue <<=16, x-=2;
sl@0: 	if(aValue < 0x1000000) x--;
sl@0: 	if(!aValue) x=0;
sl@0: 	return x;
sl@0: 	}
sl@0: 
sl@0: inline TUint BitPrecision(TUint aValue)
sl@0: 	{
sl@0: 	if(!aValue) return 0;
sl@0: 	TUint x=32;
sl@0: 	if(aValue < 0x10000)    aValue<<=16, x-=16;
sl@0: 	if(aValue < 0x1000000)  aValue<<=8, x-=8;
sl@0: 	if(aValue < 0x10000000) aValue<<=4, x-=4;
sl@0: 	if(aValue < 0x40000000) aValue<<=2, x-=2;
sl@0: 	if(aValue < 0x80000000) --x;
sl@0: 	return x;
sl@0: 	}
sl@0: 
sl@0: static const TUint RoundupSizeTable[] = {2, 2, 2, 4, 4, 8, 8, 8, 8};
sl@0:     
sl@0: static inline TUint RoundupSize(TUint n)
sl@0: 	{
sl@0:     if (n<=8)
sl@0:         return RoundupSizeTable[n];
sl@0:     else if (n<=16)
sl@0:         return 16;
sl@0:     else if (n<=32)
sl@0:         return 32;
sl@0:     else if (n<=64)
sl@0:         return 64;
sl@0:     else return 1U << BitPrecision(n-1);
sl@0: 	}
sl@0: 
sl@0: #endif