bitfield.hh revision 4258
12SN/A/* 21762SN/A * Copyright (c) 2003-2005 The Regents of The University of Michigan 32SN/A * All rights reserved. 42SN/A * 52SN/A * Redistribution and use in source and binary forms, with or without 62SN/A * modification, are permitted provided that the following conditions are 72SN/A * met: redistributions of source code must retain the above copyright 82SN/A * notice, this list of conditions and the following disclaimer; 92SN/A * redistributions in binary form must reproduce the above copyright 102SN/A * notice, this list of conditions and the following disclaimer in the 112SN/A * documentation and/or other materials provided with the distribution; 122SN/A * neither the name of the copyright holders nor the names of its 132SN/A * contributors may be used to endorse or promote products derived from 142SN/A * this software without specific prior written permission. 152SN/A * 162SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 172SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 182SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 192SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 202SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 212SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 222SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 232SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 242SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 252SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 262SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 272665Ssaidi@eecs.umich.edu * 282665Ssaidi@eecs.umich.edu * Authors: Steve Reinhardt 292665Ssaidi@eecs.umich.edu * Nathan Binkert 302SN/A */ 312SN/A 321112SN/A#ifndef __BASE_BITFIELD_HH__ 331112SN/A#define __BASE_BITFIELD_HH__ 342SN/A 353386Sgblack@eecs.umich.edu#include <inttypes.h> 362SN/A 372SN/A/** 382SN/A * Generate a 64-bit mask of 'nbits' 1s, right justified. 392SN/A */ 402SN/Ainline uint64_t 412SN/Amask(int nbits) 422SN/A{ 432SN/A return (nbits == 64) ? (uint64_t)-1LL : (1ULL << nbits) - 1; 442SN/A} 452SN/A 462SN/A 474070Ssaidi@eecs.umich.edu 482SN/A/** 492SN/A * Extract the bitfield from position 'first' to 'last' (inclusive) 502SN/A * from 'val' and right justify it. MSB is numbered 63, LSB is 0. 512SN/A */ 522SN/Atemplate <class T> 532SN/Ainline 542SN/AT 552SN/Abits(T val, int first, int last) 562SN/A{ 572SN/A int nbits = first - last + 1; 582SN/A return (val >> last) & mask(nbits); 592SN/A} 602SN/A 612SN/A/** 623814Ssaidi@eecs.umich.edu * Mask off the given bits in place like bits() but without shifting. 633814Ssaidi@eecs.umich.edu * msb = 63, lsb = 0 643814Ssaidi@eecs.umich.edu */ 653814Ssaidi@eecs.umich.edutemplate <class T> 663814Ssaidi@eecs.umich.eduinline 673814Ssaidi@eecs.umich.eduT 683814Ssaidi@eecs.umich.edumbits(T val, int first, int last) 693814Ssaidi@eecs.umich.edu{ 703814Ssaidi@eecs.umich.edu return val & (mask(first+1) & ~mask(last)); 713814Ssaidi@eecs.umich.edu} 723814Ssaidi@eecs.umich.edu 734070Ssaidi@eecs.umich.eduinline uint64_t 744070Ssaidi@eecs.umich.edumask(int first, int last) 754070Ssaidi@eecs.umich.edu{ 764070Ssaidi@eecs.umich.edu return mbits((uint64_t)-1LL, first, last); 774070Ssaidi@eecs.umich.edu} 784070Ssaidi@eecs.umich.edu 793814Ssaidi@eecs.umich.edu/** 802SN/A * Sign-extend an N-bit value to 64 bits. 812SN/A */ 822SN/Atemplate <int N> 832SN/Ainline 842SN/Aint64_t 852SN/Asext(uint64_t val) 862SN/A{ 872SN/A int sign_bit = bits(val, N-1, N-1); 882SN/A return sign_bit ? (val | ~mask(N)) : val; 892SN/A} 902SN/A 913422Sgblack@eecs.umich.edu/** 923422Sgblack@eecs.umich.edu * Return val with bits first to last set to bit_val 933422Sgblack@eecs.umich.edu */ 943422Sgblack@eecs.umich.edutemplate <class T, class B> 953422Sgblack@eecs.umich.eduinline 963422Sgblack@eecs.umich.eduT 973422Sgblack@eecs.umich.eduinsertBits(T val, int first, int last, B bit_val) 983422Sgblack@eecs.umich.edu{ 993422Sgblack@eecs.umich.edu T bmask = mask(first - last + 1) << last; 1003422Sgblack@eecs.umich.edu return ((bit_val << last) & bmask) | (val & ~bmask); 1013422Sgblack@eecs.umich.edu} 1023422Sgblack@eecs.umich.edu 1033422Sgblack@eecs.umich.edu/** 1043422Sgblack@eecs.umich.edu * A convenience function to replace bits first to last of val with bit_val 1053422Sgblack@eecs.umich.edu * in place. 1063422Sgblack@eecs.umich.edu */ 1073422Sgblack@eecs.umich.edutemplate <class T, class B> 1083422Sgblack@eecs.umich.eduinline 1093422Sgblack@eecs.umich.eduvoid 1103422Sgblack@eecs.umich.edureplaceBits(T& val, int first, int last, B bit_val) 1113422Sgblack@eecs.umich.edu{ 1123422Sgblack@eecs.umich.edu val = insertBits(val, first, last, bit_val); 1133422Sgblack@eecs.umich.edu} 1143422Sgblack@eecs.umich.edu 1154103Ssaidi@eecs.umich.edu/** 1164103Ssaidi@eecs.umich.edu * Returns the bit position of the MSB that is set in the input 1174103Ssaidi@eecs.umich.edu */ 1184103Ssaidi@eecs.umich.eduinline 1194103Ssaidi@eecs.umich.eduint 1204103Ssaidi@eecs.umich.edufindMsbSet(uint64_t val) { 1214103Ssaidi@eecs.umich.edu int msb = 0; 1224103Ssaidi@eecs.umich.edu if (!val) 1234103Ssaidi@eecs.umich.edu return 0; 1244244Ssaidi@eecs.umich.edu if (bits(val, 63,32)) { msb += 32; val >>= 32; } 1254244Ssaidi@eecs.umich.edu if (bits(val, 31,16)) { msb += 16; val >>= 16; } 1264244Ssaidi@eecs.umich.edu if (bits(val, 15,8)) { msb += 8; val >>= 8; } 1274244Ssaidi@eecs.umich.edu if (bits(val, 7,4)) { msb += 4; val >>= 4; } 1284244Ssaidi@eecs.umich.edu if (bits(val, 3,2)) { msb += 2; val >>= 2; } 1294244Ssaidi@eecs.umich.edu if (bits(val, 1,1)) { msb += 1; } 1304103Ssaidi@eecs.umich.edu return msb; 1314103Ssaidi@eecs.umich.edu} 1324103Ssaidi@eecs.umich.edu 1334258Sgblack@eecs.umich.edunamespace BitfieldBackend 1344257Sgblack@eecs.umich.edu{ 1354258Sgblack@eecs.umich.edu template<class Data> 1364258Sgblack@eecs.umich.edu class BitfieldBase 1374258Sgblack@eecs.umich.edu { 1384258Sgblack@eecs.umich.edu protected: 1394258Sgblack@eecs.umich.edu Data __data; 1404103Ssaidi@eecs.umich.edu 1414258Sgblack@eecs.umich.edu inline uint64_t 1424258Sgblack@eecs.umich.edu getBits(int first, int last) 1434258Sgblack@eecs.umich.edu { 1444258Sgblack@eecs.umich.edu return bits(__data, first, last); 1454258Sgblack@eecs.umich.edu } 1464258Sgblack@eecs.umich.edu 1474258Sgblack@eecs.umich.edu inline void 1484258Sgblack@eecs.umich.edu setBits(int first, int last, uint64_t val) 1494258Sgblack@eecs.umich.edu { 1504258Sgblack@eecs.umich.edu replaceBits(__data, first, last, val); 1514258Sgblack@eecs.umich.edu } 1524258Sgblack@eecs.umich.edu }; 1534258Sgblack@eecs.umich.edu 1544258Sgblack@eecs.umich.edu template<class Type, class Base> 1554258Sgblack@eecs.umich.edu class _BitfieldRO : public Base 1564257Sgblack@eecs.umich.edu { 1574258Sgblack@eecs.umich.edu public: 1584258Sgblack@eecs.umich.edu operator const Type () 1594258Sgblack@eecs.umich.edu { 1604258Sgblack@eecs.umich.edu return *((Base *)this); 1614258Sgblack@eecs.umich.edu } 1624258Sgblack@eecs.umich.edu }; 1634257Sgblack@eecs.umich.edu 1644258Sgblack@eecs.umich.edu template<class Type, class Base> 1654258Sgblack@eecs.umich.edu class _BitfieldWO : public Base 1664257Sgblack@eecs.umich.edu { 1674258Sgblack@eecs.umich.edu public: 1684258Sgblack@eecs.umich.edu const Type operator = (const Type & _data) 1694258Sgblack@eecs.umich.edu { 1704258Sgblack@eecs.umich.edu *((Base *)this) = _data; 1714258Sgblack@eecs.umich.edu return _data; 1724258Sgblack@eecs.umich.edu } 1734258Sgblack@eecs.umich.edu }; 1744257Sgblack@eecs.umich.edu 1754258Sgblack@eecs.umich.edu template<class Data, int first, int last=first> 1764258Sgblack@eecs.umich.edu class _Bitfield : public BitfieldBase<Data> 1774258Sgblack@eecs.umich.edu { 1784258Sgblack@eecs.umich.edu public: 1794258Sgblack@eecs.umich.edu operator const Data () 1804258Sgblack@eecs.umich.edu { 1814258Sgblack@eecs.umich.edu return this->getBits(first, last); 1824258Sgblack@eecs.umich.edu } 1834257Sgblack@eecs.umich.edu 1844258Sgblack@eecs.umich.edu const Data 1854258Sgblack@eecs.umich.edu operator = (const Data & _data) 1864258Sgblack@eecs.umich.edu { 1874258Sgblack@eecs.umich.edu this->setBits(first, last, _data); 1884258Sgblack@eecs.umich.edu return _data; 1894258Sgblack@eecs.umich.edu } 1904258Sgblack@eecs.umich.edu }; 1914258Sgblack@eecs.umich.edu 1924258Sgblack@eecs.umich.edu template <class Type, class Base> 1934258Sgblack@eecs.umich.edu class BitUnionOperators : public Base 1944257Sgblack@eecs.umich.edu { 1954258Sgblack@eecs.umich.edu public: 1964258Sgblack@eecs.umich.edu operator const Type () 1974258Sgblack@eecs.umich.edu { 1984258Sgblack@eecs.umich.edu return Base::__data; 1994258Sgblack@eecs.umich.edu } 2004257Sgblack@eecs.umich.edu 2014258Sgblack@eecs.umich.edu const Type 2024258Sgblack@eecs.umich.edu operator = (const Type & _data) 2034258Sgblack@eecs.umich.edu { 2044258Sgblack@eecs.umich.edu Base::__data = _data; 2054258Sgblack@eecs.umich.edu } 2064257Sgblack@eecs.umich.edu 2074258Sgblack@eecs.umich.edu bool 2084258Sgblack@eecs.umich.edu operator < (const Base & base) 2094258Sgblack@eecs.umich.edu { 2104258Sgblack@eecs.umich.edu return Base::__data < base.__data; 2114258Sgblack@eecs.umich.edu } 2124257Sgblack@eecs.umich.edu 2134258Sgblack@eecs.umich.edu bool 2144258Sgblack@eecs.umich.edu operator == (const Base & base) 2154258Sgblack@eecs.umich.edu { 2164258Sgblack@eecs.umich.edu return Base::__data == base.__data; 2174258Sgblack@eecs.umich.edu } 2184258Sgblack@eecs.umich.edu }; 2194258Sgblack@eecs.umich.edu} 2204257Sgblack@eecs.umich.edu 2214257Sgblack@eecs.umich.edu#define __BitUnion(type, name) \ 2224258Sgblack@eecs.umich.edu namespace BitfieldUnderlyingClasses \ 2234258Sgblack@eecs.umich.edu { \ 2244258Sgblack@eecs.umich.edu class name; \ 2254258Sgblack@eecs.umich.edu } \ 2264258Sgblack@eecs.umich.edu class BitfieldUnderlyingClasses::name { \ 2274257Sgblack@eecs.umich.edu public: \ 2284257Sgblack@eecs.umich.edu typedef type __DataType; \ 2294257Sgblack@eecs.umich.edu union { \ 2304257Sgblack@eecs.umich.edu type __data;\ 2314257Sgblack@eecs.umich.edu 2324257Sgblack@eecs.umich.edu#define EndBitUnion(name) \ 2334257Sgblack@eecs.umich.edu }; \ 2344257Sgblack@eecs.umich.edu }; \ 2354258Sgblack@eecs.umich.edu typedef BitfieldBackend::BitUnionOperators< \ 2364258Sgblack@eecs.umich.edu BitfieldUnderlyingClasses::name::__DataType, \ 2374258Sgblack@eecs.umich.edu BitfieldUnderlyingClasses::name> name; 2384257Sgblack@eecs.umich.edu 2394257Sgblack@eecs.umich.edu#define __SubBitUnion(type, name) \ 2404257Sgblack@eecs.umich.edu union { \ 2414257Sgblack@eecs.umich.edu type __data; \ 2424257Sgblack@eecs.umich.edu inline operator const __DataType () \ 2434257Sgblack@eecs.umich.edu { return __data; } \ 2444257Sgblack@eecs.umich.edu \ 2454257Sgblack@eecs.umich.edu inline const __DataType operator = (const __DataType & _data) \ 2464257Sgblack@eecs.umich.edu { __data = _data; } 2474257Sgblack@eecs.umich.edu 2484257Sgblack@eecs.umich.edu#define EndSubBitUnion(name) } name; 2494257Sgblack@eecs.umich.edu 2504258Sgblack@eecs.umich.edu//This is so we can send in parameters with commas 2514258Sgblack@eecs.umich.edu#define wrap(guts) guts 2524257Sgblack@eecs.umich.edu 2534257Sgblack@eecs.umich.edu//Read only bitfields 2544258Sgblack@eecs.umich.edu#define __BitfieldRO(base) \ 2554258Sgblack@eecs.umich.edu BitfieldBackend::_BitfieldRO<__DataType, base> 2564258Sgblack@eecs.umich.edu#define __SubBitUnionRO(name, base) \ 2574258Sgblack@eecs.umich.edu __SubBitUnion(wrap(_BitfieldRO<__DataType, base>), name) 2584257Sgblack@eecs.umich.edu 2594257Sgblack@eecs.umich.edu//Write only bitfields 2604258Sgblack@eecs.umich.edu#define __BitfieldWO(base) \ 2614258Sgblack@eecs.umich.edu BitfieldBackend::_BitfieldWO<__DataType, base> 2624258Sgblack@eecs.umich.edu#define __SubBitUnionWO(name, base) \ 2634258Sgblack@eecs.umich.edu __SubBitUnion(wrap(_BitfieldWO<__DataType, base>), name) 2644258Sgblack@eecs.umich.edu 2654258Sgblack@eecs.umich.edu//Regular bitfields 2664258Sgblack@eecs.umich.edu#define Bitfield(first, last) \ 2674258Sgblack@eecs.umich.edu BitfieldBackend::_Bitfield<__DataType, first, last> 2684258Sgblack@eecs.umich.edu#define SubBitUnion(name, first, last) \ 2694258Sgblack@eecs.umich.edu __SubBitUnion(Bitfield(first, last), name) 2704258Sgblack@eecs.umich.edu#define BitfieldRO(first, last) __BitfieldRO(Bitfield(first, last)) 2714258Sgblack@eecs.umich.edu#define SubBitUnionRO(name, first, last) \ 2724258Sgblack@eecs.umich.edu __SubBitUnionRO(Bitfield(first, last), name) 2734258Sgblack@eecs.umich.edu#define BitfieldWO(first, last) __BitfieldWO(Bitfield(first, last)) 2744257Sgblack@eecs.umich.edu#define SubBitUnionWO(name, first, last) \ 2754258Sgblack@eecs.umich.edu __SubBitUnionWO(Bitfield(first, last), name) 2764257Sgblack@eecs.umich.edu 2774257Sgblack@eecs.umich.edu#define BitUnion(type, name) __BitUnion(type, name) 2784257Sgblack@eecs.umich.edu 2794257Sgblack@eecs.umich.edu#define BitUnion64(name) __BitUnion(uint64_t, name) 2804257Sgblack@eecs.umich.edu#define BitUnion32(name) __BitUnion(uint32_t, name) 2814257Sgblack@eecs.umich.edu#define BitUnion16(name) __BitUnion(uint16_t, name) 2824257Sgblack@eecs.umich.edu#define BitUnion8(name) __BitUnion(uint8_t, name) 2834103Ssaidi@eecs.umich.edu 2841112SN/A#endif // __BASE_BITFIELD_HH__ 285